WO2017020782A1 - Battery charging and discharging control circuit and battery charging and discharging system - Google Patents

Abstract

A battery charging and discharging control circuit and a battery charging and discharging system. The battery charging and discharging control circuit comprises: a switch control component (22), a MOS transistor circuit (24), and a first resistor providing a conduction voltage to the MOS transistor circuit (24). The switch control component (22) is connected to the MOS transistor circuit (24), and configured to control switching on or off of a first MOS transistor (VT1) and a second MOS transistor (VT2) in the MOS transistor circuit (24). The MOS transistor circuit (24) comprises the first MOS transistor (VT1) and the second MOS transistor (VT2). The first MOS transistor (VT1) comprises two output pins respectively connected to two terminals of the first resistor (26), and one output pin connected to a ground. The second MOS transistor (VT2) comprises two output pins respectively connected to the two terminals of the first resistor (26), and one output pin connected to a battery. The first resistor (26) is connected to the switch control component (22). The battery charging and discharging control circuit and the battery charging and discharging system can realize control over charging and discharging of a backup battery.

Description

Battery charge and discharge control circuit and battery charge and discharge system Technical field

The present application relates to, but is not limited to, the field of circuits, and in particular, to a battery charge and discharge control circuit and a battery charge and discharge system.

Background technique

In our daily lives, batteries are often used in mobile phones, watches, razors and other items. In the communication equipment system, we also use some spare batteries to improve the reliability of the system. Under normal circumstances, the power supply supplies power to the device, and also charges the backup battery. When the utility power is lost, the power supply will stop supplying power, but the backup battery can be discharged to maintain the normal operation of the system. This also improves the stability and reliability of the communication system equipment work.

At present, the charge and discharge control of the backup battery in the industry is mainly realized by a relay. The main function of the battery is that when the battery discharge voltage is lower than a certain voltage value, the relay contacts are disconnected and the battery stops discharging, thus preventing overdischarge and damaging the battery. However, the relay control battery charge and discharge has the following disadvantages: First, the relay is bulky and costly; second, the contact of the relay is not resistant to current, easy to burn, so the reliability is not high; third is the contact resistance of the relay contact Large, so the power loss during charging and discharging is large; Fourth, only the discharge undervoltage protection function can be realized, the charging cannot be effectively controlled, and the battery can not be hot swapped.

In the related art, the problem of charge and discharge control of the backup battery cannot be achieved, and an effective solution has not been proposed.

Summary of the invention

The following is an overview of the topics detailed in this document. This Summary is not intended to limit the scope of the claims.

The utility model provides a battery charging and discharging control circuit and a battery charging and discharging system, which solves the problem that the charging and discharging control of the backup battery cannot be realized in the related art.

A battery charge and discharge control circuit comprising: a switch control component, a MOS transistor circuit and a first resistor for providing a turn-on voltage for the MOS transistor circuit; the switch control component connected to the MOS transistor circuit for controlling Conducting the first MOS transistor and the second MOS transistor in the MOS transistor circuit or Turning off; the MOS transistor circuit includes the first MOS transistor and the second MOS transistor, and two output pins of the first MOS transistor are respectively connected to two ends of the first resistor, The other output pin is grounded; the two output pins of the second MOS transistor are respectively connected to both ends of the first resistor, and the other output pin is connected to the battery; the first resistor is connected to the The switch control component.

Optionally, the battery charge and discharge control circuit further includes: a safety component for providing protection for the circuit, the safety component having one end connected to the second MOS tube and the other end connected to the battery.

Optionally, the battery charge and discharge control circuit further includes: a current detecting circuit, one end of the current detecting circuit is connected to the first MOS tube, and the other end is grounded for collecting a current signal.

Optionally, the current detecting circuit comprises: a second resistor.

Optionally, the switch control component includes: an optocoupler connected to the triode and the MOS transistor circuit for controlling conduction or deactivation of the first MOS transistor and the second MOS transistor; a triode connected to the third resistor and the optocoupler for receiving a turn-on voltage through the third resistor; the third resistor for providing a turn-on voltage to the triode.

Optionally, the switch control component includes: an optocoupler connected to the third MOS transistor and the MOS transistor circuit, configured to control whether the first MOS transistor and the second MOS transistor are turned on or off The third MOS transistor is connected to the third resistor and the optocoupler for receiving a turn-on voltage through the third resistor; the third resistor is configured to provide a guide for the third MOS transistor Through voltage.

Optionally, the switch control component includes: a relay connected to the triode and the MOS transistor circuit for controlling conduction or deactivation of the first MOS transistor and the second MOS transistor; the triode, Connected to a third resistor and the relay for receiving a turn-on voltage through the third resistor; the third resistor for providing a turn-on voltage to the transistor.

Optionally, the switch control component includes: a relay connected to the third MOS transistor and the MOS transistor circuit, configured to control whether the first MOS transistor and the second MOS transistor are turned on or off; a third MOS transistor connected to the third resistor and the relay for receiving a turn-on voltage through the third resistor; the third resistor for providing a turn-on voltage for the third MOS transistor.

Optionally, the MOS transistor circuit is connected to a negative electrode of the battery.

A battery charging and discharging system includes: the battery charging and discharging control circuit.

Through a solution of the embodiment of the present invention, a battery charge and discharge control circuit is adopted, comprising: a switch control component, a MOS transistor circuit and a first resistor for providing a turn-on voltage for the MOS transistor circuit; and a switch control component connected to the MOS a tube circuit for controlling conduction or deactivation of the first MOS transistor and the second MOS transistor in the MOS transistor circuit; the MOS transistor circuit includes a first MOS transistor and a second MOS transistor, and two outputs of the first MOS transistor The pins are respectively connected to both ends of the first resistor, and the other output pin is grounded; two output pins of the second MOS transistor are respectively connected to both ends of the first resistor, and the other output pin is connected to the battery The first resistor is connected to the switch control assembly. The problem that the charge and discharge control of the backup battery cannot be realized in the related art is solved, and the control of charging and discharging of the backup battery is realized.

BRIEF abstract

1 is a block diagram showing the structure of a battery charge and discharge control circuit according to an embodiment of the present invention;

2 is a general plan diagram of a system for charging and discharging a backup battery of an embodiment of the present invention;

3 is a schematic view showing the working principle of a backup battery charging and discharging control circuit according to an embodiment of the present invention;

4 is a first circuit diagram of an embodiment of the present invention using an optocoupler as a switch control device;

5 is a second circuit diagram of an embodiment of the present invention using an optocoupler as a switch control device;

6 is a third circuit diagram of an embodiment of the present invention using an optocoupler as a switch control device;

Figure 7 is a circuit diagram of a relay as a switch control device in accordance with an embodiment of the present invention.

Embodiments of the invention

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

It should be noted that the terms "first", "second" and the like in the specification and claims of the embodiments of the present invention and the above drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or Prioritization.

In the embodiment, a battery charging and discharging control circuit is provided. FIG. 1 is a structural block diagram of a battery charging and discharging control circuit according to an embodiment of the present invention. As shown in FIG. 1 , the battery charging and discharging control circuit includes: a switch control. The component 21, the MOS transistor circuit 22 and a first resistor 23 for supplying a turn-on voltage to the MOS transistor circuit. Switch control component 21, connected to MOS transistor circuit 22 for control The first MOS transistor and the second MOS transistor are turned on or off in the MOS transistor circuit 22; the MOS transistor circuit 22 includes a first MOS transistor and a second MOS transistor, and the two output pins of the first MOS transistor are respectively The first resistor 23 is connected at both ends, and the other output pin is grounded; the two output pins of the second MOS transistor are respectively connected to both ends of the first resistor 23, and the other output pin is connected to the battery; the first resistor 23, connected to the switch control assembly 21.

The above-mentioned device included in the present invention solves the problem that the charge and discharge control of the backup battery cannot be realized in the related art, and further realizes the control of charging and discharging of the backup battery.

In an alternative embodiment, the battery charge and discharge control circuit further includes: a fuse assembly for providing protection to the circuit, the fuse assembly having one end coupled to the second MOS transistor and the other end coupled to the battery. In order to make the battery short circuit, it can be quickly disconnected to prevent the current from being too dangerous.

In an optional embodiment, the battery charge and discharge control circuit further includes: a current detecting circuit having one end connected to the first MOS transistor and the other end grounded for collecting a current signal. In another alternative embodiment, the current sensing circuit described above can be a second resistor.

The switch control component can have various implementations. In an optional embodiment, the switch control component includes: an optocoupler connected to the triode and the MOS transistor circuit for controlling the first MOS transistor and the second MOS The transistor is turned on or off; the transistor is connected to the third resistor and the optocoupler for receiving a turn-on voltage through the third resistor; the third resistor is configured to provide a turn-on voltage for the transistor. In another optional embodiment, the switch control component includes: an optocoupler connected to the third MOS transistor and the MOS transistor circuit for controlling whether the first MOS transistor and the second MOS transistor are turned on or off The third MOS transistor is connected to the third resistor and the optocoupler for receiving the turn-on voltage through the third resistor; the third resistor is configured to provide a turn-on voltage for the third MOS transistor. In still another optional embodiment, the switch control component includes: a relay connected to the triode and the MOS transistor circuit for controlling conduction or deactivation of the first MOS transistor and the second MOS transistor; the triode being connected And a relay for receiving a turn-on voltage through the third resistor; the third resistor is configured to provide a turn-on voltage for the transistor. In another optional embodiment, the switch control component includes: a relay connected to the third MOS transistor and the MOS transistor circuit for controlling whether the first MOS transistor and the second MOS transistor are turned on or off; a third MOS transistor connected to the third resistor and the relay for receiving a turn-on voltage through the third resistor; the third resistor for providing a turn-on voltage for the third MOS transistor.

In an alternative embodiment, the MOS transistor circuit is coupled to the negative terminal of the battery.

According to another aspect of an embodiment of the present invention, a battery charging and discharging system is further provided, comprising: the battery charging and discharging control circuit described above.

The main purpose of the embodiments of the present invention is to provide a backup battery charging and discharging control circuit that has the advantages of miniaturization, intelligence, high efficiency, high efficiency, and high reliability.

The embodiment of the utility model adopts the following technical solutions:

2 is a schematic diagram of a system of a backup battery charging and discharging control circuit according to an embodiment of the present invention. The overall scheme of the battery backup and discharge control circuit of the present embodiment is shown in FIG. 2: mainly by the following functions Module composition: AC-DC AC-DC power module, system load, backup battery, battery monitoring module, single-chip control module, battery charge and discharge control circuit module. The main function of the AC-DC power module is to convert the utility power into the system load and the voltage required by the battery to supply power to the system load, and at the same time to charge the backup battery; the system load is each function block that needs to be powered in the entire communication system; The backup battery can continue to supply power to the load through the discharge after the mains power is turned off, so that the normal operation of the system can be maintained; the main function of the battery monitoring module is to monitor the voltage, temperature, presence and reverse of the battery. And reported to the single-chip microcomputer; and the MCU control module is responsible for monitoring the battery charge and discharge in addition to controlling the AC-DC power supply module; the battery charge and discharge control circuit module is the execution unit of the battery charge and discharge control, and its main function is to accept the single-chip control The control signal of the system realizes the purpose of battery charge and discharge control.

3 is a schematic diagram of the working principle of the charging and discharging control circuit of the backup battery of the present invention. The working principle of the battery charging and discharging control circuit is shown in FIG. 3: the charging and discharging control circuit is composed of the following parts: a switch and a control circuit switch, The top MOS: VT1 and VT2, and the resistor resistor and fuse connected to the GS pole of the top MOS. The working principle diagram of the battery charge and discharge control circuit has the following signals: 1) VCC: an auxiliary power supply voltage provided by the power supply module, the function of which is to provide the driving voltage for the top MOS tube of the control circuit; 2) battery-: battery Negative, the battery diagram on the working principle diagram is connected to the top MOS and the system ground GND. In practice, the circuit can also be connected in series with a fuse and current sense resistor; 3) GND: power output ground and system ground.

The basic working principle of the above battery charge and discharge control circuit is that the switch and the control circuit switch are turned on and off to control the turn-on and turn-off of the top MOS transistors VT1 and VT2; when the switch circuit is turned on, the auxiliary power supply voltage VCC, the resistance resistor VT1's body diode and GND form a A current loop, the resistor will generate a voltage due to the current, the size of which is VR=VCC-0.7V, 0.7V is the conduction voltage drop of the diode in the MOSFET VT1 (the diode conduction voltage drop of different types of MOS tube will be Different). Once VR is greater than the GS threshold voltage of the MOS transistor, the DS poles of VT1 and VT2 will change from the off state to the saturated conduction state, so that the battery can perform the charging and discharging functions. When the switch and the control circuit switch are in the off state, no current flows through the resistance resistor, so the voltage is 0V, that is, the GS voltage of the MOS transistors VT1 and VT2 is 0V, so the two MOSs are in the off state, and thus There will be current flowing through the DS poles of the two MOS transistors. At this time, the power supply cannot charge the battery, and the battery cannot discharge the system.

The switch and control circuit switch is represented by two contacts in the working principle diagram. In fact, the circuit uses some electronic devices to jointly realize the switching function, and the turn-on and turn-off are controlled by the single-chip control signal.

2 is a schematic diagram of a system of a backup battery charging and discharging control circuit according to an embodiment of the present invention. The entire system requires an AC-DC power module, a single-chip control module, a battery monitoring module, a charge and discharge control circuit module, and a backup battery and other functional modules. Cooperate with each other to realize intelligent control of battery charge and discharge.

3 is a schematic diagram of the working principle of the backup battery charging and discharging control circuit according to the embodiment of the present invention. The switch and the control circuit switch are turned on and off to control the on and off of the top MOS transistors VT1 and VT2, thereby realizing battery charging and discharging control. the goal of. There are two implementations of the switch and control circuit switch. One is to use the optocoupler as the switch control device. This scheme has three circuit connections, as shown in Figure 4, Figure 5 and Figure 6. The other solution is to use the relay. Take the switch control device, the circuit connection is shown in Figure 7.

1. Implementation of optocoupler as a switching control device:

1) The first circuit connection method:

There are three circuit connections for using optocouplers as a means of switching control devices. The first method is shown in Figure 4. This method is suitable for the case where the VCC size and the operating voltage of the microcontroller are inconsistent. In this circuit connection mode, the negative battery of the battery - and the circuit connected to the top MOS transistors VT1 and VT2 are connected in series with a fuse FU1 and a resistor R6. When the battery is short-circuited, the fuse FU1 can be quickly disconnected to prevent a current from being excessively generated and causing a fire. The resistor R6 is a current detecting resistor, and the current signal BAT_IS of the parameter is transmitted to the single chip microcomputer and other control circuits. When BATCTL is high, Transistor VT3 is driven by resistor R1, so that VCC, the body diode of the optocoupler's primary side and the collector of VT3 form a current loop. The diode in the optocoupler will have current flowing through it, resulting in the internal triode of the optocoupler's secondary side. Saturated conduction. Therefore, a current flows through the PIN3 and PIN4 pins of the photocoupler D1, and the body diode flowing through the resistor R5 and the optocoupler VT1 flows back to GND. Thus, the GS voltages of the top MOS transistors VT1 and VT2 are turned on more than the threshold voltage, and the battery can be charged and discharged. When BATCTL is low, the transistor VT3 is in the off state, and the diode in the primary side of the optocoupler D1 will not have current flowing, so it is also in the off state. The resistor R5 also does not have a current flowing, so the GS voltage to the top MOS transistors VT1 and VT2 is 0V, and thus is also in an off state, so the battery can neither be charged nor discharged. In actual use, the VT3 transistor can also be replaced by a MOS tube. The 1 pin of VT3 corresponds to the G pole of the MOS tube, the 2 pin corresponds to the S pole of the MOS tube, and the 3 pin corresponds to the D pole of the MOS tube.

2) The second circuit connection method:

FIG. 5 is a second circuit diagram of the embodiment of the present invention using an optocoupler as a switch control device. The method is to directly drive the optocoupler D1 by using a single chip microcomputer, and is suitable for the case where the VCC voltage and the working voltage of the single chip are the same. When BATCTL is low, current will flow through the resistor R3 and the diode in the primary side of the optocoupler D1, and the secondary side of the optocoupler D1 will be in a saturated conduction state. Therefore, a current flows through the PIN3 and PIN4 pins of the photocoupler D1, and the body diode flowing through the resistor R5 and the optocoupler VT1 flows back to GND. Thus, the GS voltages of the top MOS transistors VT1 and VT2 are turned on more than the threshold voltage, and the battery can be charged and discharged. When BATCTL is at a high level, the diode in the primary side of the optocoupler D1 does not have a current flow because there is no voltage difference. Therefore, the phototransformer D1 secondary transistor is in an off state, and the resistor R5 does not have a current flowing, so the top is The GS voltages of the MOS transistors VT1 and VT2 are 0 V, and thus are in an off state, so that the battery can neither be charged nor discharged.

3) The third circuit connection method:

FIG. 6 is a third circuit diagram of the embodiment of the present invention using an optocoupler as a switch control device, which is also used to directly drive the optocoupler D1. When BATCTL is high, current will flow through the resistor R3 and the diode in the primary side of the optocoupler D1, and the secondary side of the optocoupler D1 will be in a saturated conduction state. Therefore, a current flows through the PIN3 and PIN4 pins of the photocoupler D1, and the body diode flowing through the resistor R5 and the optocoupler VT1 flows back to GND. This is the top MOS tube VT1 and VT2 The GS voltage will be greater than the threshold voltage and the battery will be charged and discharged. When BATCTL is low, the diode in the primary side of the optocoupler D1 does not have a current flow because there is no voltage difference. Therefore, the phototransformer D1 secondary transistor is in the off state, and the resistor R5 does not have current flowing, so the top is The GS voltages of the MOS transistors VT1 and VT2 are 0 V, and thus are in an off state, so that the battery can neither be charged nor discharged.

2. The use of relays as a switch control device implementation:

Fig. 7 is a circuit diagram of a relay as a switch control device according to an embodiment of the present invention. This mode is similar to the above-described first circuit connection method in that the relay K1 is used instead of the photocoupler D1. When BATCTL is high, transistor VT3 is turned on by resistor R1, so that VCC, the coil of relay K1 and the collector of VT3 form a current loop, and the relay coil current flows to cause the contact of the relay to close. Therefore, a current flowing through the resistor R5 and the body diode of the optocoupler VT1 flows back to GND. Thus, the GS voltages of the top MOS transistors VT1 and VT2 are turned on more than the threshold voltage, and the battery can be charged and discharged. When BATCTL is low, transistor VT3 is in the off state, and there is no current flowing through the coil of relay K1, so the contact of relay K1 is in the off state. Since the resistor R5 thus does not have a current flowing, the GS voltage to the top MOS transistors VT1 and VT2 is 0 V, and thus is in an off state, so that the battery can neither be charged nor discharged. In actual use, the VT3 transistor can also be replaced by a MOS tube. The 1 pin of VT3 corresponds to the G pole of the MOS tube, the 2 pin corresponds to the S pole of the MOS tube, and the 3 pin corresponds to the D pole of the MOS tube.

In summary, according to the present invention, a relay is often used as a control switch or a separate charge and discharge control as compared with conventional battery charge and discharge control. The utility model adopts two pairs of top MOS as control switches, and has the following advantages:

Control is simple and reliable. The control circuit device has few components, and can effectively control the whole process of charging and discharging the battery. Under the monitoring of the single-chip control circuit, the battery charging and discharging can realize the hot plugging, anti-reverse connection and other intelligent functions, and the single chip can also be used for the battery. Temperature rise, voltage, current and other conditions are monitored. If abnormal conditions occur, they can be processed in time. This not only ensures stable operation of the system, but also ensures safe use of the battery and improves battery life.

Energy saving and low loss. The MOS transistor has a small on-resistance of the DS pole, and the MOS transistor is a voltage-driven device. Therefore, the power consumption of the circuit relative to the relay is smaller during the charging and discharging process of the battery. The purpose of energy saving.

long lasting. The electric shock of the relay is easily damaged and deteriorated due to the high temperature caused by the discharge during the turn-on and turn-off process, and the MOS tube has better impact resistance, so the service life is longer and the reliability is higher.

small volume. The MOS tube is smaller than the relay and can save more space.

The above is only an alternative embodiment of the present invention, and is not intended to limit the embodiments of the present invention. For those skilled in the art, the present invention may be variously modified and changed. Any modifications, equivalent substitutions, improvements, etc. within the spirit and scope of the embodiments of the present invention are intended to be included within the scope of the present invention.

Industrial applicability

Through a solution of the embodiment of the present invention, a battery charge and discharge control circuit is adopted, comprising: a switch control component, a MOS transistor circuit and a first resistor for providing a turn-on voltage for the MOS transistor circuit; and a switch control component connected to the MOS a tube circuit for controlling conduction or deactivation of the first MOS transistor and the second MOS transistor in the MOS transistor circuit; the MOS transistor circuit includes a first MOS transistor and a second MOS transistor, and two outputs of the first MOS transistor The pins are respectively connected to both ends of the first resistor, and the other output pin is grounded; two output pins of the second MOS transistor are respectively connected to both ends of the first resistor, and the other output pin is connected to the battery The first resistor is connected to the switch control assembly. The problem that the charge and discharge control of the backup battery cannot be realized in the related art is solved, and the control of charging and discharging of the backup battery is realized.

Claims (9)

A battery charge and discharge control circuit comprising: a switch control component, a metal oxide semiconductor field effect transistor MOS transistor circuit and a first resistor for providing a turn-on voltage for the MOS transistor circuit; The switch control component is connected to the MOS transistor circuit for controlling conduction or shutdown of the first MOS transistor and the second MOS transistor in the MOS transistor circuit; The MOS transistor circuit includes the first MOS transistor and the second MOS transistor, two output pins of the first MOS transistor are respectively connected to two ends of the first resistor, and the other output tube The ground is connected to the battery; the two output pins of the second MOS tube are respectively connected to both ends of the first resistor, and the other output pin is connected to the battery; The first resistor is coupled to the switch control assembly. The battery charge and discharge control circuit according to claim 1, further comprising: A fuse assembly for providing protection to a circuit, one end of the fuse assembly being coupled to the second MOS tube and the other end coupled to the battery. The battery charge and discharge control circuit according to claim 1, further comprising: a current detecting circuit having one end connected to the first MOS transistor and the other end grounded for collecting a current signal. The battery charge and discharge control circuit according to claim 2, wherein said switch control component comprises: An optocoupler connected to the triode and the MOS transistor circuit for controlling conduction or deactivation of the first MOS transistor and the second MOS transistor; The triode is connected to the third resistor and the optocoupler for receiving a turn-on voltage through the third resistor; The third resistor is configured to provide a turn-on voltage for the transistor. The battery charge and discharge control circuit according to claim 2, wherein said switch control component comprises: An optocoupler connected to the third MOS transistor and the MOS transistor circuit for controlling the first Turning on or off the MOS transistor and the second MOS transistor; The third MOS transistor is connected to the third resistor and the optocoupler for receiving a turn-on voltage through the third resistor; The third resistor is configured to provide a turn-on voltage for the third MOS transistor. The battery charge and discharge control circuit according to claim 2, wherein said switch control component comprises: a relay connected to the triode and the MOS transistor circuit for controlling conduction or deactivation of the first MOS transistor and the second MOS transistor; The triode is connected to the third resistor and the relay for receiving a turn-on voltage through the third resistor; The third resistor is configured to provide a turn-on voltage for the transistor. The battery charge and discharge control circuit according to claim 2, wherein said switch control component comprises: a relay connected to the third MOS transistor and the MOS transistor circuit for controlling conduction or shutdown of the first MOS transistor and the second MOS transistor; The third MOS transistor is connected to the third resistor and the relay for receiving a turn-on voltage through the third resistor; The third resistor is configured to provide a turn-on voltage for the third MOS transistor. The battery charge and discharge control circuit according to any one of claims 1 to 7, wherein said MOS transistor circuit is connected to a negative electrode of said battery. A battery charge and discharge system comprising: the battery charge and discharge control circuit according to any one of claims 1 to 8.

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