WO2020232924A1 - Wide-range constant-power converter circuit - Google Patents

Abstract

Disclosed is a wide-range constant-power converter circuit. The circuit comprises a first transformer module (210), a second transformer module (220), a first primary-side input module (110) arranged on a primary side of the first transformer module (210), a first secondary-side output module (310) arranged on a secondary side of the first transformer module (210), a second primary-side input module (120) arranged on a primary side of the second transformer module (220), a second secondary-side output module (320) arranged on a secondary side of the second transformer module (220), a high/low-voltage mode control module (400) for controlling the first secondary-side output module (310) and the second secondary-side output module (320) to be connected in series in a high-voltage mode and to be connected in parallel in a low-voltage mode, and a load output module (500) for receiving a serial output voltage or parallel output voltage of the first secondary-side output module (310) and the second secondary-side output module (320). The wide-range constant-power converter circuit can realize ultra-wide-range constant-power charging and can rapidly charge vehicles at different voltage levels.

Description

A wide-range constant power converter circuit Technical field

The present invention relates to the field of power supply modules, and more specifically, to a wide-range constant power converter circuit.

Background technique

As a new type of transportation, new energy electric vehicles have incomparable advantages in alleviating energy crisis and managing urban air quality, and represent the direction of future automobile development. The construction of charging facilities such as electric vehicle charging stations is the prerequisite and foundation for the healthy development of the electric vehicle industry. Charging facilities mainly include AC charging piles and DC fast charging piles. The charging power module is the core component of DC charging piles. The development of its technology has attracted the attention of industry customers. From the perspective of the voltage range of electric vehicles, usually the voltage of a car is about 350V, the voltage of a medium-sized bus is 400-500V, and the voltage of a bus is 600V. Modules with different voltage ranges are designed for different vehicles. There are usually two specifications of charging power supply modules. One is a low-voltage module with a constant power range of 375~500V, and the other is a high-voltage module with a constant power range of 600~750V. In addition, there are a small amount of higher voltage modules in demand, with a constant power range of 750~1000V. In short, in order to charge different cars, different types of modules need to be designed. For charging power module manufacturers, more products need to be designed. For charging pile operators, they need to buy different modules and design different charging piles. First, the cost is more expensive, and second, more manpower and material resources are required. . These are not conducive to reducing costs and improving product competitiveness. Therefore, there is a need for a wide-range constant power converter circuit that can take both high and low voltages into consideration and realize a wide range of high and low voltage constant power output.

technical problem

The technical problem to be solved by the present invention is to provide a wide-range constant power converter circuit that takes both high and low voltage into consideration and realizes a wide range of high and low voltage constant power output in response to the above-mentioned defects of the prior art.

Technical solutions

The technical solution adopted by the present invention to solve its technical problem is to construct a wide-range constant power converter circuit, including a first transformer module, a second transformer module, and a first primary side arranged on the primary side of the first transformer module Input module, a first secondary side output module arranged on the secondary side of the first transformer module, a second primary side input module arranged on the primary side of the second transformer module, and a second primary side input module arranged on the secondary side of the second transformer module A second secondary side output module, and a high and low voltage mode control module for controlling the first secondary side output module and the second secondary side output module to be connected in series in high voltage mode and in parallel in low voltage mode, and for receiving The first secondary side output module and the second secondary side output module output voltage in series or a load output module that outputs voltage in parallel.

In the wide-range constant power converter circuit of the present invention, the first transformer module includes at least a first transformer network and a second transformer network, and the primary sides of the first transformer network and the second transformer network are connected in series , The secondary side of the first transformer network and the second transformer network are respectively connected to the first secondary side output module, the second transformer module includes at least a third transformer network and a fourth transformer network, the third The primary side of the transformer network and the fourth transformer network are connected in series, and the secondary side of the third transformer network and the fourth transformer network are respectively connected to the second secondary side output module.

In the wide-range constant power converter circuit of the present invention, the first secondary output module includes a first rectification network, a second rectification network, and a first voltage equalization network, and the second secondary output module includes a first Three rectification networks, a fourth rectification network and a second voltage equalization network, the input end of the first rectification network is connected to the secondary side of the first transformer network, and the output end is connected to the fourth voltage equalization network via the first voltage equalization network The input end of the second rectification network is connected to the secondary side of the second transformer network, and the output end is connected to the input end of the third rectification network via the second voltage equalization network. The input end of the three rectification network is also connected to the secondary side of the third rectification network, the input end of the fourth rectification network is also connected to the secondary side of the fourth rectification network, the first rectification network and the third The output ends of the rectification network are respectively connected to the input end of the load output module and the input end of the high and low voltage mode control module, and the output ends of the second rectification network and the fourth rectification network are respectively connected to the load The output terminal of the output module and the output terminal of the high and low voltage mode control module.

In the wide-range constant power converter circuit of the present invention, the high and low voltage mode control module includes a first switch, a second switch, and a third switch, and the first switch is connected to the high and low voltage. Between the first terminal and the second terminal of the mode control module, the second switch is connected between the first terminal of the high and low voltage mode control module and the second terminal of the load output module, and the third The switch is connected between the second end of the high and low voltage mode control module and the first end of the load output module.

In the wide-range constant power converter circuit of the present invention, the first transformer network and the second transformer network respectively include one transformer or more than one transformer connected in series with each other.

In the wide-range constant power converter circuit of the present invention, the first voltage equalization network and the second voltage equalization network respectively include at least one voltage equalization unit, and each voltage equalization unit includes at least one diode connected in series. Branch and at least one LC resonant branch.

In the wide-range constant power converter circuit of the present invention, the diode series voltage dividing branch includes at least a pair of series diodes, a central connection point of the at least one pair of series diodes is a voltage dividing point, and the LC resonance The branch includes at least one set of resonant inductors and resonant capacitors connected in series.

In the wide-range constant power converter circuit of the present invention, it further includes a third transformer module, a third primary side input module provided on the primary side of the third transformer module, and a third primary side input module provided on the secondary side of the third transformer module. The high and low voltage mode control module is further configured to control the first secondary side output module, the second secondary side output module, and the third secondary side output module to be connected in series in the high voltage mode In the parallel connection in the low voltage mode, the load output module is used to receive the series output voltage or the parallel output voltage of the first secondary side output module, the second secondary side output module, and the third secondary side output module.

In the wide-range constant power converter circuit of the present invention, the first rectification network, the second rectification network, the third rectification network, and the fourth rectification network include a diode full-bridge rectifier unit, a switch tube full-bridge rectifier unit, Diode half-bridge rectifier unit, and/or switch tube half-bridge rectifier unit; and/or

The wide-range constant power converter circuit further includes a first filter module provided between the first secondary side output module and the high and low voltage mode control module, and a first filter module provided between the second secondary side output module and the control module. A second filter module between the high and low voltage mode control modules and a third filter module arranged between the third secondary output module and the high and low voltage mode control module.

In the wide-range constant power converter circuit of the present invention, the first primary input module, the second primary input module, and the third primary input module respectively include the originals connected in series with the first transformer module. The switching network and the capacitor inductance network of the primary side of the second transformer module and the primary side of the third transformer module.

Beneficial effect

Implementing the wide-range constant power converter circuit of the present invention, by controlling the first secondary side output module and the second secondary side output module to be connected in series in the high voltage mode and in parallel in the low voltage mode, it is possible to achieve coverage The ultra-wide range constant power charging of 1000V~250V high and low voltage electric vehicles can quickly charge vehicles of different voltage levels. Further, when working in low voltage mode, it is equivalent to a topology in which the primary windings of the transformer are connected in series and the secondary windings are connected in parallel, which can realize natural voltage equalization and current equalization. When working in high voltage mode, it is equivalent to the series connection of the primary windings of the transformer and the cross series connection of the secondary windings, which can naturally share current. Furthermore, at least two voltage equalizing networks including a diode series voltage dividing branch and an LC resonance branch are set, and the diode series voltage dividing branch in the other branch is cross-connected through the LC resonance branch, which can solve the difference in device parameters. The resulting serious voltage imbalance problem can meet the needs of high voltage and high power; and the LC resonant branch does not require special logic control, which greatly reduces the cost and improves the reliability of the circuit.

Description of the drawings

The present invention will be further described below in conjunction with the accompanying drawings and embodiments. In the accompanying drawings:

Figure 1 is a schematic block diagram of a first preferred embodiment of a wide-range constant power converter circuit of the present invention;

2 is a schematic block diagram of a second preferred embodiment of the wide-range constant power converter circuit of the present invention;

3a~3c are circuit diagrams of preferred embodiments of the switching network of the wide-range constant power converter circuit of the present invention;

4 is a circuit diagram of a preferred embodiment of the transformer module of the wide-range constant power converter circuit of the present invention;

5a to 5d are circuit diagrams of preferred embodiments of the capacitor-inductor combination of the wide-range constant power converter circuit of the present invention;

6a to 6d are circuit diagrams of a preferred embodiment of the rectifier network of the wide-range constant power converter circuit of the present invention;

Figures 7a-7b are circuit diagrams of preferred embodiments of the secondary output module of the wide-range constant power converter circuit of the present invention;

FIG. 8 is a circuit diagram of the third preferred embodiment of the wide-range constant power converter circuit of the present invention;

9 is a circuit diagram of the fourth preferred embodiment of the wide-range constant power converter circuit of the present invention;

10 is a circuit diagram of the fifth preferred embodiment of the wide-range constant power converter circuit of the present invention;

11 is a circuit diagram of the sixth preferred embodiment of the wide-range constant power converter circuit of the present invention;

Fig. 12 is a circuit diagram of the seventh preferred embodiment of the wide-range constant power converter circuit of the present invention.

The best mode of the invention

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention.

The present invention relates to a wide-range constant power converter circuit, which includes a first transformer module, a second transformer module, a first primary input module arranged on the primary side of the first transformer module, and a first primary input module arranged on the first transformer module. The first secondary side output module of the secondary side, the second primary side input module provided on the primary side of the second transformer module, the second secondary side output module provided on the secondary side of the second transformer module, and the control module The first secondary side output module and the second secondary side output module are connected in series in the high voltage mode and in parallel in the low voltage mode high and low voltage mode control module, and used to receive the first secondary side output module and the The series output voltage of the second secondary output module or the load output module of parallel output voltage. Implementing the wide-range constant power converter circuit of the present invention, by controlling the first secondary side output module and the second secondary side output module to be connected in series in the high voltage mode and in parallel in the low voltage mode, it is possible to achieve coverage The ultra-wide range constant power charging of 1000V~250V high and low voltage electric vehicles can quickly charge vehicles of different voltage levels.

Fig. 1 is a schematic block diagram of the first preferred embodiment of the wide-range constant power converter circuit of the present invention. As shown in Figure 1, a wide-range constant power converter circuit of the present invention includes a transformer module 210, a transformer module 220, a primary input module 110 arranged on the primary side of the transformer module 210, and a primary input module 110 arranged on the primary side of the transformer module 210. 210 the secondary side output module 310 on the secondary side, the primary side input module 120 provided on the primary side of the transformer module 220, the secondary side output module 320 provided on the secondary side of the transformer module 220, and the secondary side for controlling the secondary side The output module 310 and the secondary side output module 320 are connected in series in the high voltage mode and in parallel in the low voltage mode high and low voltage mode control module 400, and used to receive the secondary side output module 310 and the secondary side output module 320 Load output modules 500 that output voltage in series or in parallel.

In a preferred embodiment of the present invention, the transformer modules 210, 220, the primary input modules 110, 120, the secondary output modules 310, 320, the high and low voltage mode control module 400, and the load output module 500 can all adopt this field Any relevant module structure known in. Based on the teaching of the present invention, those skilled in the art can construct different types of related modules to realize the present invention.

In a preferred embodiment of the present invention, the transformer module 210 and the transformer module 220 may include at least two transformer networks connected in series, and each transformer network may include at least one transformer, or two or more transformers connected in series. . In a preferred embodiment of the present invention, the primary input module 110 and the primary input module 120 may respectively include a switch network and a capacitor inductance network connected in series to the primary sides of the transformer modules 210 and 220 respectively. The secondary side output modules 310 and 320 may include a rectification unit and a filter unit connected to the secondary side of the transformer modules 210 and 220 in sequence. The high and low voltage mode control module 400 may include a plurality of switch devices connected between the secondary side output modules 310 and 320, relays, switch tubes, etc., as long as it can realize the secondary side The output modules 310 and 320 can be switched in parallel or in series.

In a further preferred embodiment of the present invention, the wide-range constant power converter circuit may further include a third transformer module, a third primary input module arranged on the primary side of the third transformer module, and The third secondary side output module of the secondary side of the third transformer module, the high and low voltage mode control module 400 is further used to control the secondary side output module 310, the secondary side output module 320, and the third secondary side output module In series connection in the high voltage mode and parallel connection in the low voltage mode, the load output module 500 is used to receive the series output voltage or parallel output of the secondary side output module 310, the secondary side output module 320, and the third secondary side output module Voltage. The third transformer module, the third primary input module, and the third secondary output module can be constructed with reference to the transformer modules 210 and 220, the primary input modules 110 and 120, and the secondary output modules 310 and 320, respectively.

Implementing the wide-range constant power converter circuit of the present invention, by controlling the first secondary side output module and the second secondary side output module to be connected in series in the high voltage mode and in parallel in the low voltage mode, it is possible to achieve coverage The ultra-wide range constant power charging of 1000V~250V high and low voltage electric vehicles can quickly charge vehicles of different voltage levels. When working in low voltage mode, it is equivalent to the topology of the transformer primary winding in series and the secondary winding in parallel, which can realize natural voltage and current sharing. When working in high voltage mode, it is equivalent to the series connection of the primary windings of the transformer and the cross series connection of the secondary windings, which can naturally share current.

Fig. 2 is a schematic block diagram of the second preferred embodiment of the wide-range constant power converter circuit of the present invention. As shown in FIG. 2, a wide-range constant power converter circuit of the present invention includes a first transformer module 210, a second transformer module 220, and a first primary input module arranged on the primary side of the first transformer module 210 110. The first secondary output module 310 arranged on the secondary side of the first transformer module 210, the second primary input module 120 arranged on the primary side of the second transformer module 220, and the second primary input module 120 arranged on the second transformer module 220 A second secondary output module 320 of the secondary side, and a high and low voltage mode for controlling the first secondary output module 310 and the second secondary output module 320 to be connected in series in the high voltage mode and in parallel in the low voltage mode A control module 400 and a load output module 500 for receiving serial output voltages or parallel output voltages of the first secondary output module 310 and the second secondary output module 320.

Further, as shown in FIG. 2, the first primary input module 110 further includes a first switch network 111 and a first capacitor-inductor network 112 connected in series to the primary side of the first transformer module 210 respectively. The second primary input module 120 further includes a second switch network 121 and a second capacitive inductance network 122 connected in series to the primary side of the second transformer module 220 respectively. The first transformer module 210 includes at least a first transformer network 211 and a second transformer network 212, the primary sides of the first transformer network 211 and the second transformer network 212 are connected in series, the first transformer network 211 and the second transformer network 212 The secondary side is respectively connected to the first secondary side output module 310, the second transformer module 220 includes at least a third transformer network 221 and a fourth transformer network 222, the third transformer network 221 and the fourth transformer network 222 The primary sides are connected in series, and the secondary sides of the third transformer network 221 and the fourth transformer network 222 are respectively connected to the second secondary output module 320. As further shown in FIG. 2, the first secondary output module 310 includes a first rectification network 311, a second rectification network 312, and a first voltage equalization network 313, and the second secondary output module 320 includes a third rectification network 321, a fourth rectification network 322 and a second voltage equalization network 323, the input end of the first rectification network 311 is connected to the secondary side of the first transformer network 211, and the output end is connected to the all The input end of the fourth rectification network 322, the input end of the second rectification network 312 is connected to the secondary side of the second transformer network 212, and the output end is connected to the third rectification network via the second voltage equalization network 323 The input end of the third rectification network 321 is also connected to the secondary side of the third rectification network 321, and the input end of the fourth rectification network 322 is also connected to the secondary side of the fourth rectification network 322 The output ends of the first rectification network 311 and the third rectification network 321 are respectively connected to the input end of the load output module 500 and the input end of the high and low voltage mode control module 400, and the second rectification network The output terminals of 312 and the fourth rectification network 322 are both connected to the output terminal of the load output module 500 and the output terminal of the high and low voltage mode control module 400 respectively.

In a preferred embodiment of the present invention, the first switch network 111 and the second switch network 121 can be of the same circuit connection structure, which can be a full-bridge topology, a symmetrical half-bridge or an asymmetrical half-bridge. Bridge topology, as shown in Figure 3(a)~ (c) Shown.

In a preferred embodiment of the present invention, the first transformer network 211, the second transformer network 212, the third transformer network 221, and the fourth transformer network 222 each include a transformer, the primary inductance of which can be the same as the primary inductance of the transformer. The side windings are connected in parallel, where the primary inductance can be a separately designed inductance or an integrated design in the transformer. For example, the first transformer network 211 may include a transformer Ta1 whose equivalent inductance is Lma1, and the second transformer network 212 includes a transformer Ta2 whose equivalent inductance is Lma2, which is finally equivalent to an inductance Lm. The inductance Lm can be the equivalent of integrated or separately designed inductances Lma1 and Lma12, or a separately designed inductance Lm, both of which are within the protection scope of this patent. The same is true for the third transformer network 221 and the fourth transformer network 222. Of course, the first transformer network 211, the second transformer network 212, the third transformer network 221, and the fourth transformer network 222 may also include multiple transformers, respectively.

As shown in Figure 4, a transformer module can include two transformer networks, and each transformer network includes two transformers. Therefore, a transformer module can include four transformers Ta1, Ta2, Ta3, and T1a4. As shown in Figure 4, transformer Ta1 It is connected in series with the primary winding of Ta2, the primary winding of transformer Ta3 and T1a4 are connected in series, the secondary winding of transformer Ta1 and Ta3 are connected in series, and the secondary winding of transformer Ta3 and T1a4 are connected in series. In the same way, other transformer modules can also be constructed similarly. Of course, in other preferred embodiments of the present invention, the actual number of transformers in the transformer network or the number of transformer networks in the transformer module can be adjusted according to actual needs. In a further preferred embodiment of the present invention, the various transformer networks can be connected in series with each other or in parallel with each other.

In a preferred embodiment of the present invention, as shown in Figures 5a-5d, the inductor-capacitor combination may be an LLC series resonant converter composed of an inductor Lr, an inductor Lm (equivalent inductance), and a capacitor Cr; it may be an inductor Lr, SRC series resonant converter composed of capacitor Cr; can be PRC parallel resonant converter composed of inductor Lr and capacitor Cr (capacitor and transformer are connected in parallel); it can also be LCC series parallel resonant converter composed of inductor Lr, capacitor Cr, and capacitor Cpr Device. For example, the inductor-capacitor combination is an LLC series resonant converter, the three elements of inductor Lr, inductor Lm and capacitor Cr are connected in series, and the position of each other in series can be changed arbitrarily. Capacitor Cr can be placed before inductor Lr, or placed between Lr and inductor Lm Both are within the protection scope of this patent. The three elements of the inductor Lr, the inductor Lm and the capacitor Cr can also be split into a plurality of inductors or capacitors in series and parallel, and placed in series in any position, which is also within the protection scope of this patent. When the inductor Lr is split into multiple inductors, it can be a single inductor or a mutual coupling inductor.

In a preferred embodiment of the present invention, the first rectification network 311, the second rectification network 312, the third rectification network 321, and the fourth rectification network 322 may include a diode full bridge rectifier unit, a switch tube full bridge rectifier unit, and a diode half The bridge rectifier unit and/or the switch tube half-bridge rectifier unit are shown in Figure 6a-6d.

In a preferred embodiment of the present invention, the first voltage equalization network 313 and the second voltage equalization network 323 may include at least one voltage equalization unit, and each voltage equalization unit includes at least one diode series voltage dividing branch and at least one LC resonance branch. The diode series voltage dividing branch includes at least one pair of series diodes, a central connection point of the at least one pair of series diodes is a voltage dividing point, and the LC resonance branch includes at least one set of series-connected resonant inductors and resonant capacitors. In a preferred embodiment of the present invention, the positions of the resonant inductor and the resonant capacitor can be exchanged. The first voltage equalization network 313 and the second voltage equalization network 323 may include multiple voltage equalization units.

Figures 7a-7b show circuit diagrams of a preferred secondary side output module of the present invention. In the embodiment shown in FIG. 7a, the secondary side output module includes full-bridge rectifier networks 311 and 312 each composed of four diodes. Each full bridge network 311 and 312 is connected to the filter module 600 via a voltage equalization network. The output of the filter module 600 is connected to the load output module 500. As shown in FIG. 7a, each voltage equalization network may include two voltage equalization units, and each voltage equalization unit includes an LC resonance branch and a diode series voltage dividing branch. Therefore, the inductors L1-L4 and the capacitors C1-C4 connected in series respectively constitute four voltage equalizing units. The capacitors D1-D8 connected in series with each other constitute four diode series voltage dividing branches. As shown in Figure 7a, one end of the LC resonant branch formed by the inductor L1 and the capacitor C1 is connected to an output end of the full bridge network 311, and the other end is cross-connected to the voltage dividing point of the diode series voltage dividing branch formed by diodes D5 and D7. In the same way, one end of the LC resonant branch formed by the inductor L2 and the capacitor C2 is connected to the other output end of the full-bridge network 311, and the other end is cross-connected to the voltage dividing point of the diode series voltage dividing branch formed by diodes D6 and D8. One end of the LC resonance branch formed by the inductor L3 and the capacitor C3 is connected to an output end of the full-bridge network 312, and the other end is cross-connected to the voltage dividing point of the diode series voltage dividing branch formed by diodes D1 and D3. Similarly, the inductor L4 and One end of the LC resonance branch formed by the capacitor C4 is connected to the other output end of the full-bridge network 312, and the other end is cross-connected to the voltage dividing point of the diode series voltage dividing branch formed by diodes D2 and D4. In a further preferred embodiment of the present invention, the positions of the capacitors and inductors in series with each other in the LC resonant branch can be changed arbitrarily. The capacitors can be placed before or after the inductors, and their positions can be staggered or split into separate parts. Multiple inductors or capacitors are connected in series and parallel. As shown in Fig. 7b, each voltage equalization network may include only one voltage equalization unit, and each full-bridge network 311 and 312 are respectively connected to only one voltage equalization unit. In addition, in addition to the connection relationship shown in FIGS. 7a-7b, the voltage equalization unit can be arranged at any position of the full bridge network 311 and 312. Furthermore, in a further preferred embodiment of the present invention, the positions of the LC resonance branch and the diode series voltage divider branch can also be interchanged. For example, the LC resonance branch can be arranged on the side close to the filter module, and the diode series The voltage dividing branch is arranged on the side close to the rectifier network, and any such arrangement manner falls within the protection scope of the present invention. In the embodiment shown in Figs. 7a-7b, the filter module is a capacitor filter module, which may also adopt inductance-capacitor filtering and multiple filter methods of inductance-capacitor combination.

In a preferred embodiment of the present invention, the high and low voltage mode control module 400 includes a first switch, a second switch, and a third switch. The first switch is connected to the high and low voltage mode control module 400. Between the first terminal and the second terminal, the second switch is connected between the first terminal of the high and low voltage mode control module 400 and the second terminal of the load output module 500, and the third switch It is connected between the second end of the high and low voltage mode control module 400 and the first end of the load output module 500. Preferably, the first switch, the second switch and the third switch may be switch tubes, relays, contactors and other devices that can be turned on and off.

Implementing the wide-range constant power converter circuit of the present invention, by controlling the first secondary side output module and the second secondary side output module to be connected in series in the high voltage mode and in parallel in the low voltage mode, it is possible to achieve coverage The ultra-wide range constant power charging of 1000V~250V high and low voltage electric vehicles can quickly charge vehicles of different voltage levels. Further, when working in low voltage mode, it is equivalent to a topology in which the primary windings of the transformer are connected in series and the secondary windings are connected in parallel, which can realize natural voltage equalization and current equalization. When working in high voltage mode, it is equivalent to the series connection of the primary windings of the transformer and the cross series connection of the secondary windings, which can naturally share current. Furthermore, at least two voltage equalizing networks including a diode series voltage dividing branch and an LC resonance branch are set, and the diode series voltage dividing branch in the other branch is cross-connected through the LC resonance branch, which can solve the difference in device parameters. The resulting serious voltage imbalance problem can meet the needs of high voltage and high power; and the LC resonant branch does not require special logic control, which greatly reduces the cost and improves the reliability of the circuit.

Fig. 8 is a circuit diagram of the third preferred embodiment of the wide-range constant power converter circuit of the present invention. As shown in Figure 8, the wide-range constant power converter circuit of the present invention includes a switching network composed of two full-bridge switching tubes, and two sets of transformer networks composed of two transformers connected in series. The first transformer network is composed of transformer Ta1. The two input ends of the full-bridge diode rectification network 311 are connected to the output end of the transformer Ta1, and the two output ends are connected to the filter module. The two input ends of the full-bridge diode rectification network 312 are connected to the output end of the transformer Ta2. Two output terminals are connected to the filter module. Similarly, the second transformer network is composed of transformer Tb1 and transformer Tb2. Two input ends of the full-bridge diode rectifier network 312 are connected to the output end of the transformer Tb1, and the two output ends are connected to the filter module. The input end is connected to the output end of the transformer Tb2, and the two output ends are connected to the filter module. The diode series voltage dividing branch composed of diodes D1 and D2 in series is connected to the two output ends of the full-bridge diode rectifier network 311, and its voltage dividing point is connected to one input end of the full-bridge diode rectifier network 322 via an LC resonant branch. The diode series voltage dividing branch composed of diodes D3 and D4 in series is also connected to the two output ends of the full-bridge diode rectifier network 311, and its voltage dividing point is connected to the other of the full-bridge diode rectifier network 322 via another LC resonant branch. Input terminal. Similarly, the diode series voltage dividing branch composed of diodes D4 and D5 in series is connected to the two output ends of the full-bridge diode rectifier network 312, and its voltage dividing point is connected to one of the full-bridge diode rectifier network 321 via an LC resonant branch. At the input, the diode series voltage dividing branch composed of diodes D7 and D8 connected in series is connected to the two output ends of the full-bridge diode rectifier network 312, and its voltage dividing point is connected to the other of the full-bridge diode rectifier network 321 via an LC resonant branch. One input. In this preferred embodiment, the filter module includes a filter capacitor C01 connected in series between the first end of the load R0 and the first end of the high and low voltage mode control module, and a filter capacitor C01 connected in series between the second end of the load R0 and the high and low voltage mode control module. The filter capacitor C02 between the second end.

In this embodiment, the high and low voltage mode control module includes a first switch K1, a second switch K2, and a third switch K3. The first switch K1 is connected to the high and low voltage mode control module 400. Between the first terminal and the second terminal, the second switch K2 is connected to the first terminal of the high and low voltage mode control module 400 and the second terminal of the load R0, and the third switch K3 is connected to the Between the second end of the high and low voltage mode control module 400 and the first end of the load R0. At the same time, the first end of the high and low voltage mode control module 400 is respectively connected to an output end of the full-bridge diode rectification network 311 and 321, and the second end is respectively connected to an output end of the full-bridge diode rectification network 321 and 322. In this way, when charging a low-voltage electric vehicle, the low-voltage mode is selected, and through the control logic, the switch K1 is turned off, and the switches K2 and K3 are closed to realize the constant power output in the low-voltage mode. When charging an electric vehicle in a high-voltage range, the high-voltage mode is selected, and through the control logic, the switch K1 is closed, K2, and K3 are disconnected to realize the constant power output in the high-voltage mode.

The wide-range constant power converter circuit of the present invention includes a switching network composed of two full-bridge switching tubes, and two sets of transformer networks composed of two transformers connected in series. The first transformer network is composed of a transformer Ta1 and a transformer Ta2. The two input ends of the bridge diode rectifier network 311 are connected to the output end of the transformer Ta1, the two output ends are connected to the filter module, the two input ends of the full bridge diode rectification network 312 are connected to the output end of the transformer Ta2, and the two output ends are connected to the filter module . Similarly, the second transformer network is composed of transformer Tb1 and transformer Tb2. Two input ends of the full-bridge diode rectifier network 312 are connected to the output end of the transformer Tb1, and the two output ends are connected to the filter module. The input end is connected to the output end of the transformer Tb2, and the two output ends are connected to the filter module. The diode series voltage dividing branch composed of diodes D1 and D2 in series is connected to the two output ends of the full-bridge diode rectifier network 311, and its voltage dividing point is connected to one input end of the full-bridge diode rectifier network 322 via an LC resonant branch. The diode series voltage dividing branch composed of diodes D3 and D4 in series is also connected to the two output ends of the full-bridge diode rectifier network 311, and its voltage dividing point is connected to the other of the full-bridge diode rectifier network 322 via another LC resonant branch. Input terminal. Similarly, the diode series voltage dividing branch composed of diodes D4 and D5 in series is connected to the two output ends of the full-bridge diode rectifier network 312, and its voltage dividing point is connected to one of the full-bridge diode rectifier network 321 via an LC resonant branch. At the input, the diode series voltage dividing branch composed of diodes D7 and D8 connected in series is connected to the two output ends of the full-bridge diode rectifier network 312, and its voltage dividing point is connected to the other of the full-bridge diode rectifier network 321 via an LC resonant branch. One input. In this preferred embodiment, the filter module includes a filter capacitor C01 connected in series between the first end of the load R0 and the first end of the high and low voltage mode control module, and a filter capacitor C01 connected in series between the second end of the load R0 and the high and low voltage mode control module. The filter capacitor C02 between the second end.

In this embodiment, the high and low voltage mode control module includes a first switch K1, a second switch K2, and a third switch K3. The first switch K1 is connected to the high and low voltage mode control module 400. Between the first terminal and the second terminal, the second switch K2 is connected to the first terminal of the high and low voltage mode control module 400 and the second terminal of the load R0, and the third switch K3 is connected to the Between the second end of the high and low voltage mode control module 400 and the first end of the load R0. At the same time, the first end of the high and low voltage mode control module 400 is respectively connected to an output end of the full-bridge diode rectification network 311 and 321, and the second end is respectively connected to an output end of the full-bridge diode rectification network 321 and 322. In this way, when charging a low-voltage electric vehicle, the low-voltage mode is selected, and through the control logic, the switch K1 is turned off, and the switches K2 and K3 are closed to realize the constant power output in the low-voltage mode. When charging an electric vehicle in a high-voltage range, the high-voltage mode is selected, and through the control logic, the switch K1 is closed, K2, and K3 are disconnected to realize the constant power output in the high-voltage mode.

Implementing the wide-range constant power converter circuit of the present invention, by controlling the first secondary side output module and the second secondary side output module to be connected in series in the high voltage mode and in parallel in the low voltage mode, it is possible to achieve coverage The ultra-wide range constant power charging of 1000V~250V high and low voltage electric vehicles can quickly charge vehicles of different voltage levels. Further, when working in low voltage mode, it is equivalent to a topology in which the primary windings of the transformer are connected in series and the secondary windings are connected in parallel, which can realize natural voltage equalization and current equalization. When working in high voltage mode, it is equivalent to the series connection of the primary windings of the transformer and the cross series connection of the secondary windings, which can naturally share current. Furthermore, at least two voltage equalizing networks including a diode series voltage dividing branch and an LC resonance branch are set, and the diode series voltage dividing branch in the other branch is cross-connected through the LC resonance branch, which can solve the difference in device parameters. The resulting serious voltage imbalance problem can meet the needs of high voltage and high power; and the LC resonant branch does not require special logic control, which greatly reduces the cost and improves the reliability of the circuit.

Fig. 9 is a circuit diagram of the fourth preferred embodiment of the wide-range constant power converter circuit of the present invention. As shown in Figure 9, the wide-range constant power converter circuit of the present invention includes two primary side input modules, two transformer modules, two secondary side output modules, one high and low voltage mode control module, two filter modules, and one Load output module. Each primary input module includes a switch network and a capacitor and inductor network. Each transformer module includes two transformer networks, and each secondary output module includes two rectifier networks and a voltage equalization network.

In this embodiment, each switch network includes two first and second full-bridge networks of switching transistors connected in parallel, and each full-bridge network of switching transistors includes four switching transistors. Each transformer network includes two transformers connected in series on the primary side. Each capacitor and inductor network includes a series of capacitors and inductors. Each rectification network includes a rectification network composed of four diodes. Each voltage equalization network includes a diode series voltage divider branch composed of two diodes connected in series and an LC resonance branch composed of series capacitors and inductors. Each filter module includes a filter capacitor. The high and low voltage mode control module includes three switches, and the load output module includes one load.

As shown in Figure 9, the switching tubes Sa1-Sa8 constitute the first switching network, the switching tubes Sb1-Sb8 constitute the second switching network, the transformer Ta1-Ta2 constitute the first transformer network, the transformer Ta3-Ta4 constitute the second transformer network, and the transformer Tb1 -Tb2 constitutes the third transformer network, transformers Tb3-Tb4 constitutes the fourth transformer network, the first capacitor inductance network constituted by the capacitor Cra1 and the resistor Lra1 connects the output terminal of the first switching network and the primary side of the first transformer network, the capacitor Cra2 and The second capacitor and inductor network formed by the resistor Lra2 connects the output terminal of the second switch network and the primary side of the second transformer network, and the third capacitor and inductor network formed by the capacitor Cra3 and the resistor Lra3 connects the output terminal of the third switch network and the third transformer On the primary side of the network, the fourth capacitor and inductance network formed by the capacitor Cra4 and the resistor Lra4 is connected to the output end of the fourth switch network and the primary side of the fourth transformer network. The rectification networks 311-312 and 321-322 formed by four diodes are respectively connected to the output terminals of the transformer Ta1-Ta2, the transformer Ta3-Ta4, the transformer Tb1-Tb2, and the transformer Tb3-Tb4. The diode series voltage dividing branch composed of diodes D1 and D2 in series is connected to the two output ends of the full-bridge diode rectifier network 311, and its voltage dividing point is connected to one input end of the full-bridge diode rectifier network 322 via an LC resonant branch. The diode series voltage dividing branch composed of diodes D3 and D4 in series is also connected to the two output ends of the full-bridge diode rectifier network 311, and its voltage dividing point is connected to the other of the full-bridge diode rectifier network 322 via another LC resonant branch. Input terminal. Similarly, the diode series voltage dividing branch composed of diodes D4 and D5 in series is connected to the two output ends of the full-bridge diode rectifier network 312, and its voltage dividing point is connected to one of the full-bridge diode rectifier network 321 via an LC resonant branch. At the input, the diode series voltage dividing branch composed of diodes D7 and D8 connected in series is connected to the two output ends of the full-bridge diode rectifier network 312, and its voltage dividing point is connected to the other of the full-bridge diode rectifier network 321 via an LC resonant branch. One input. In this preferred embodiment, the filter module includes a filter capacitor C01 connected in series between the first end of the load R0 and the first end of the high and low voltage mode control module, and a filter capacitor C01 connected in series between the second end of the load R0 and the high and low voltage mode control module. The filter capacitor C02 between the second end.

In this embodiment, the high and low voltage mode control module includes a first switch K1, a second switch K2, and a third switch K3. The first switch K1 is connected to the high and low voltage mode control module 400. Between the first terminal and the second terminal, the second switch K2 is connected to the first terminal of the high and low voltage mode control module 400 and the second terminal of the load R0, and the third switch K3 is connected to the Between the second end of the high and low voltage mode control module 400 and the first end of the load R0. At the same time, the first end of the high and low voltage mode control module 400 is respectively connected to an output end of the full-bridge diode rectification network 311 and 321, and the second end is respectively connected to an output end of the full-bridge diode rectification network 321 and 322. In this way, when charging a low-voltage electric vehicle, the low-voltage mode is selected, and through the control logic, the switch K1 is turned off, and the switches K2 and K3 are closed to realize the constant power output in the low-voltage mode. When charging an electric vehicle in a high-voltage range, the high-voltage mode is selected, and through the control logic, the switch K1 is closed, K2, and K3 are disconnected to realize the constant power output in the high-voltage mode.

In a further preferred embodiment of the present invention, each switch network may only use a full bridge network composed of four switch tubes, see the embodiment shown in FIG. 10.

In a further preferred embodiment of the present invention, it may include a topology structure composed of three sets of transformer modules, a primary side input module, and a secondary side output module. Refer to the embodiment shown in FIG. 11. Those skilled in the art further understand that there may also be four or five or more sets of topological structures composed of transformer modules, primary input modules, and secondary output modules, all of which fall within the protection scope of the present invention.

In a further preferred embodiment of the present invention, the number of transformers in each group of transformer modules can be the same or different, and each voltage equalization network can include only one group of voltage equalization networks, that is, only one LC resonance branch. Circuit and a diode series voltage divider branch, as shown in Figure 12. Further, in each group, the composition of the transformer module, the primary side input module, and the secondary side output module may be the same or different.

In the embodiment shown in Figs. 10-12, the principle is similar to that of the embodiment shown in Fig. 9, and will not be repeated here. Those skilled in the art know that the various modules disclosed in the present invention can be combined according to actual conditions to form a new implementation, which will not be listed here. Those skilled in the art can implement various such circuits based on the teaching of the present invention.

Although the present invention is described through specific embodiments, those skilled in the art should understand that various changes and equivalent substitutions can be made to the present invention without departing from the scope of the present invention. In addition, various modifications can be made to the present invention for specific situations or materials without departing from the scope of the present invention. Therefore, the present invention is not limited to the disclosed specific embodiments, but should include all embodiments falling within the scope of the claims of the present invention.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement and improvement made within the spirit and principle of the present invention shall be included in the protection of the present invention. Within range.

Claims (10)

A wide-range constant power converter circuit, characterized in that it comprises a first transformer module, a second transformer module, a first primary input module arranged on the primary side of the first transformer module, and a first primary input module arranged on the primary side of the first transformer module. The first secondary output module on the secondary side of the module, the second primary input module provided on the primary side of the second transformer module, the second secondary output module provided on the secondary side of the second transformer module, and A high and low voltage mode control module that controls the first secondary output module and the second secondary output module to be connected in series in the high voltage mode and in parallel in the low voltage mode, and is used to receive the first secondary output module and the The series output voltage of the second secondary output module or the load output module of parallel output voltage. The wide-range constant power converter circuit according to claim 1, wherein the first transformer module includes at least a first transformer network and a second transformer network, the first transformer network and the second transformer network The primary side of the first transformer network and the secondary side of the second transformer network are respectively connected to the first secondary side output module, and the second transformer module includes at least a third transformer network and a fourth transformer network, The primary sides of the third transformer network and the fourth transformer network are connected in series, and the secondary sides of the third transformer network and the fourth transformer network are respectively connected to the second secondary side output module. The wide-range constant power converter circuit according to claim 2, wherein the first secondary side output module includes a first rectification network, a second rectification network, and a first voltage equalization network, and the second secondary side The output module includes a third rectification network, a fourth rectification network, and a second voltage equalization network. The input end of the first rectification network is connected to the secondary side of the first transformer network, and the output end is connected through the first voltage equalization network. The input end of the fourth rectification network, the input end of the second rectification network is connected to the secondary side of the second transformer network, and the output end is connected to the input end of the third rectification network via the second voltage equalization network The input end of the third rectification network is also connected to the secondary side of the third rectification network, the input end of the fourth rectification network is also connected to the secondary side of the fourth rectification network, the first rectification network and The output ends of the third rectification network are respectively connected to the input end of the load output module and the input end of the high and low voltage mode control module, and the output ends of the second rectification network and the fourth rectification network are respectively connected Connect the output terminal of the load output module and the output terminal of the high and low voltage mode control module. The wide-range constant power converter circuit according to claim 3, wherein the high and low voltage mode control module comprises a first switch, a second switch and a third switch, and the first switch is connected to Between the first terminal and the second terminal of the high and low voltage mode control module, and the second switch is connected between the first terminal of the high and low voltage mode control module and the second terminal of the load output module, The third switch is connected between the second end of the high and low voltage mode control module and the first end of the load output module. The wide-range constant power converter circuit according to claim 4, wherein the first transformer network and the second transformer network respectively comprise one transformer or more than one transformer connected in series. The wide-range constant power converter circuit according to claim 4, wherein the first voltage equalization network and the second voltage equalization network respectively comprise at least one voltage equalization unit, and each voltage equalization unit includes at least one The diode connects the voltage dividing branch and at least one LC resonance branch in series. The wide-range constant power converter circuit according to claim 6, wherein the diode series voltage dividing branch includes at least one pair of series diodes, and a central connection point of the at least one pair of series diodes is a voltage dividing point, The LC resonant branch includes at least one set of resonant inductors and resonant capacitors connected in series. The wide-range constant power converter circuit according to any one of claims 1-7, further comprising a third transformer module, a third primary input provided on the primary side of the third transformer module Module, a third secondary output module provided on the secondary side of the third transformer module, the high and low voltage mode control module is further used to control the first secondary output module, the second secondary output module and the second The three secondary side output modules are connected in series in the high voltage mode and in parallel in the low voltage mode, and the load output module is used to receive the output of the first secondary side output module, the second secondary side output module, and the third secondary side output module. Series output voltage or parallel output voltage. The wide-range constant power converter circuit according to claim 8, wherein the first rectification network, the second rectification network, the third rectification network, and the fourth rectification network comprise a diode full bridge rectifier unit, a switch tube full Bridge rectifier unit, diode half-bridge rectifier unit, and/or switch tube half-bridge rectifier unit; and/or the wide-range constant power converter circuit further includes an output module arranged on the first secondary side and the high and low voltage A first filter module between the mode control modules, a second filter module provided between the second secondary output module and the high and low voltage mode control module, and a second filter module provided between the third secondary output module and the The third filter module between the high and low voltage mode control modules. The wide-range constant power converter circuit according to claim 8, wherein the first primary input module, the second primary input module and the third primary input module respectively comprise serially connected to the first A transformer module primary side, a switch network and a capacitor inductance network of the primary side of the second transformer module and the primary side of the third transformer module.