WO2013177757A1 - Led light adjustment driver and led light source system - Google Patents

Description

 LED dimming driver and LED light source system

 The present invention relates to a dimming driver for adjusting the brightness of an LED light source, and to an LED light source system using the dimming driver.

Background technique

 As the luminous efficacy of LEDs continues to increase, the application of LED light sources into the field of lighting has become an irresistible trend. As shown in Figure 1, the LED has a nonlinear relationship between the operating voltage and the current, and the operating voltage of each LED is discrete. In practical applications, the operating current of the LED must be accurately controlled, otherwise the LED will be irreversible. damage. Therefore, as shown in Fig. 2, in the existing LED light source system, most of the LED driving power source adopts the constant current control type power source 100 to ensure the operational reliability of the LED.

 LED light source for illumination usually needs to be dimmed. At present, the size of the constant current is generally adjusted or the current chopping duty ratio is adjusted. This dimming method is effective for fixedly connected LED lamps, but For LED luminaires that use non-fixed connections (such as wire lights, track lights, etc.), the load changes due to the movement or addition or subtraction of the luminaire. After a fixed current, the single LED light source may cause excessive current damage or shunt. The problem of too little current illuminating darkening or even illuminating. Therefore, dimming non-fixedly connected LED luminaires by adjusting the current does not meet the requirements for reliable operation of the luminaire.

 In view of the above problems in practical applications, the object of the present invention is to provide a method for determining the highest voltage output and continuously modulating within a certain range, and providing an initial voltage value to the LED lamp by manual adjustment of the user to ensure that the LED is at the most The working voltage in the dark state is based on this point as the reference point, and the stepping dimming is performed between the highest point of the voltage, that is, the brightest point. Since the highest voltage is known, the light source also uses this highest voltage as the rated voltage. In the single lamp module of the LED, the voltage is matched, that is, the number of series is connected, and an appropriate current limiting resistor is connected in a single series circuit to ensure Current deviation due to LED nonlinearity or dispersion.

Summary of the invention

One of the technical problems to be solved by the present invention is to provide an LED dimming driver that overcomes the present LED dimming drivers cannot meet the shortcomings of dimming requirements for non-fixed-connected LED lamps.

 The second technical problem to be solved by the present invention is to provide an LED light source system that overcomes the shortcomings of the existing LED light source system that cannot meet the dimming requirements of non-fixed connection LED lamps.

 The technical solution adopted by the present invention to solve one of the technical problems is: constructing an LED dimming driver, comprising: an electromagnetic interference filter circuit, a rectifier circuit, a power factor correction circuit, and a high frequency DC/DC buck isolation conversion Circuit, PWM control circuit, output voltage feedback control circuit, initial voltage regulator, D/A conversion circuit, MCU chip, isolated optocoupler A and isolated optocoupler B; said electromagnetic interference filter circuit, rectifier circuit, power factor correction a circuit, a high frequency DC/DC buck conversion circuit is sequentially connected, an output end of the high frequency DC/DC buck conversion circuit is an output end of the LED dimming driver, and an input end of the power factor correction circuit is the LED tune Optical drive input

3⁄4 ;

 The input end of the PWM control circuit is connected to the output end of the isolation optocoupler A, and the output end is connected to the control end of the high frequency DC/DC buck isolation conversion circuit;

 The initial voltage regulating component is connected to the input end of the MCU, and the output end of the MCU is connected to the output voltage feedback control circuit via the D/A conversion circuit, and then connected to the input end of the isolated optocoupler A; the input end of the MCU is connected to the isolated optocoupler B, and the optocoupler B is isolated. The input end is connected to the switch dimming port, and the output voltage feedback control circuit is simultaneously connected to the output end of the LED dimming driver;

 The LED dimming driver control port control signal value upper limit corresponds to the LED dimming driver output terminal output voltage upper limit, the LED dimming driver control port control signal value lower limit corresponding to the LED dimming driver output terminal output voltage driving LED load lamp group The starting voltage of the work.

 In the LED dimming driver of the present invention, the control signal of the LED dimming driver control port is a standard dimming interface DC1—10V voltage, or the control signal of the LED dimming driver control port is a standard dimming interface DC4- 20MA current.

 In the LED dimming driver of the present invention, the output voltage of the output of the LED dimming driver is limited to 12 volts, and the upper limit of the voltage value of the control port of the LED dimming driver is 10 volts, and the lower limit is 1 volt; or the LED is adjusted. The upper limit of the output voltage of the optical driver output is 12 volts. The upper limit of the current value of the LED dimming driver control port is 20 mA and the lower limit is 4 mA.

The technical solution adopted by the present invention to solve the second technical problem thereof is: constructing an LED light source system The system includes an LED dimming driver and a plurality of LED lamp groups connected in parallel at the output end of the LED dimming driver, wherein:

 The LED dimming driver comprises an electromagnetic interference filter circuit, a rectifier circuit, a power factor correction circuit, a high frequency DC/DC buck isolation conversion circuit, a PWM control circuit, an output voltage feedback control circuit, a starting voltage regulator, and a D/A Conversion circuit, MCU chip, isolated optocoupler A and isolated optocoupler B;

 The electromagnetic interference filter circuit, the rectifier circuit, the power factor correction circuit, and the high frequency DC/DC buck conversion circuit are sequentially connected, and the output end of the high frequency DC/DC buck conversion circuit is an output end of the LED dimming driver. The input of the power factor correction circuit is an input of the LED dimming driver

3⁄4 ;

 The input end of the PWM control circuit is connected to the output end of the isolation optocoupler A, and the output end is connected to the control end of the high frequency DC/DC buck isolation conversion circuit;

 The initial voltage regulating component is connected to the input end of the MCU, and the output end of the MCU is connected to the output voltage feedback control circuit via the D/A conversion circuit, and then connected to the input end of the isolated optocoupler A; the input end of the MCU is connected to the isolated optocoupler B, and the optocoupler B is isolated. The input end is connected to the switch dimming port, and the output voltage feedback control circuit is simultaneously connected to the output end of the LED dimming driver;

 The LED dimming driver control port control signal value upper limit corresponds to the LED dimming driver output terminal output voltage upper limit, the LED dimming driver control port control signal value lower limit corresponding to the LED dimming driver output terminal output voltage driving LED load lamp group Starting voltage of work;

 Each of the LED lamp sets includes a current limiting element and a plurality of LED lamps connected in series.

 In the LED light source system of the present invention, the control signal of the LED dimming driver control port is a standard dimming interface DC1-10V voltage, or the control signal of the LED dimming driver control port is a standard dimming interface DC4-20MA Current.

 In the LED light source system of the present invention, the output voltage of the output of the LED dimming driver is limited to 12 volts, and the upper limit of the voltage value of the control port of the LED dimming driver is 10 volts, and the lower limit is 1 volt; or the LED dimming The output voltage of the driver output is limited to 12 volts. The upper limit of the current value of the LED dimming driver control port is 20 mA and the lower limit is 4 mA.

In the LED light source system of the present invention, the current limiting element is a resistor. The LED dimming driver and the LED light source system embodying the present invention have the beneficial effects compared with the prior art:

 1. It not only satisfies the continuous dimming of fixed-connected LED luminaires, but also satisfies the continuous dimming of non-fixed-connected LED luminaires.

 2. Simple structure and easy to implement.

DRAWINGS

 The present invention will be further described with reference to the accompanying drawings and embodiments in which:

 Figure 1 is an LED illumination characteristic curve.

 2 is a circuit diagram of an embodiment of a conventional LED light source system.

 3 is a circuit schematic diagram of an embodiment of an LED dimming driver of the present invention.

 4 is a circuit diagram of an embodiment of an LED light source system of the present invention.

detailed description

 As shown in FIG. 3, the LED dimming driver 1 of the present invention includes an EMI filter circuit (Electromagnetic Interference) 101, a rectifier circuit 102, a PFC circuit (Power Factor Correction) 103, and a high frequency DCVDC step-down isolation converter. Circuit 105, PWM control circuit (Pulse Width Modulation) 104, output voltage feedback control circuit 2, initial voltage regulator 110, D/A conversion circuit 108, MCU chip 109, isolated optocoupler A107 and isolated optocoupler B106 .

 The EMI filter circuit 101, the rectifier circuit 102, the PFC circuit 103, and the high frequency DCVDC buck isolation conversion circuit 105 are sequentially connected. The output end of the high frequency DC/DC buck isolation conversion circuit 105 is the output end 3 of the LED dimming driver 1; the input end of the EMI filter circuit 101 is the input end of the LED dimming driver 1, and the rectifying circuit 102 can include However, it is not limited to a full bridge rectifier circuit, a half bridge rectifier circuit, and the like.

 The control terminal of the PWM control circuit 104 is connected to the control terminal of the high frequency DC/DC buck isolation conversion circuit 105, and the input terminal of the PWM control circuit 104 is connected to the output terminal of the isolation optocoupler A107. The PWM control circuit 104 is simultaneously connected to the output terminal of the rectifier circuit 102 and the PFC circuit 103, respectively.

The output voltage feedback control circuit 2 is connected to the control terminal of the high frequency DC/DC buck isolation conversion circuit 105 through the isolation optocoupler A, and the MCU chip 109 is connected to the input terminal of the D/A conversion circuit 108, D/A. The output of the conversion circuit 108 is connected to the output voltage feedback control circuit 2, and the input of the output voltage feedback control circuit 2 is connected to the two outputs of the LED dimming driver.

 The starting voltage regulator 110 can include, but is not limited to, a long handle hand potentiometer, a semi-adjustable potentiometer, a trimmer potentiometer, a sealed precision potentiometer, a controllable digital potentiometer, a dial switch combination, and the like.

 The control terminal of the MCU chip 109 is the control port of the LED dimming driver 1. The adjustment signal of the control port 9 can be a standard dimming interface DC1-10V voltage or a standard dimming interface DC4-20MA current. The signal input end of the MCU chip 109 is connected to the output of the isolation optocoupler 106, and the input end of the isolation optocoupler 106 is connected to the switch dimming port 10 of the LED dimming driver 1. The MCU chip 109 is used for signal processing and control output.

 The switch dimming control port 10 is a SWITCH-DIM dimming control port, and a voltage signal is applied to the port through the switch, and the output voltage of the LED dimming driver output terminal is slowly adjusted from the upper limit to the starting voltage of the LED load lamp group operation, or The starting voltage from the operation of the LED load lamp group is slowly adjusted to the upper limit voltage of the LED load lamp group. During the upward adjustment or downward adjustment, once the dimmer switch is turned off, the LED dimming driver stays in this state.

 The upper limit of the control signal value of the control port of the LED dimming driver 1 corresponds to the upper limit of the output voltage of the output of the LED dimming driver 1, and the lower limit of the control port value of the control port of the LED dimming driver 1 corresponds to the output voltage of the output of the LED dimming driver 1. The starting voltage at which the LED load lamp group operates. This starting voltage is manually implemented manually.

 LED dimming driver 1 The control port control signal can be either a voltage signal or a current signal. For example, when the upper limit of the output voltage of the LED dimming driver 1 is 12 volts, the upper limit of the control port voltage signal of the LED dimming driver 1 is set to 10 volts, the lower limit is 1 volt; or when the output voltage of the LED dimming driver output is When the upper limit is 12 volts, the upper limit of the control port current signal value of the LED dimming driver 1 is set to 20 mA, and the lower limit is 4 mA.

As shown in FIG. 4, the LED light source system of the present invention comprises an LED dimming driver 1 and a plurality of LED lamp groups connected in parallel to the output end of the LED dimming driver 1 (the LED lamp groups 5, 6, 7, 8 are shown in the figure). ). The LED dimming driver 1 adopts the above LED dimming driver, and details are not described herein. Each LED lamp group includes a current limiting component 11 and a plurality of LED lamps 12 connected in series, and the current limiting component 11 can adopt a resistor or a constant current diode. Wait. In this embodiment, a plurality of LED light groups are connected to the lamp pull wire or the lamp track 4, and the LED dimming driver 1 is provided, and the dimming control port control signal is a 1-10V or 4-20mA universal dimming port, and the LED dimming The upper limit voltage of the output of the driver 1 is DC12V, and the LED lamp group is 3-4 LEDs in series (the number of LED lamps depends on the operating voltage of the specific LED lamp). To make the LED light from no light to near light, the initial voltage is usually about 1/3 of its rated voltage. In this embodiment, the LED light group is weakly illuminated by the user manually adjusting the output starting voltage adjusting member 2. At this time, the MCU chip in the LED dimming driver 1 dims the voltage as the LED lamp to the darkest. The lowest voltage, at the same time, the range between the highest voltage DC12V output by the LED dimming driver 1 is classified, for example, 512 or 1024. The initial voltage is relative to the IV state or 4 mA state of the control port 9 of the LED dimming driver 1, and DC12V corresponds to the 10 V state or the 20 mA state of the control port 9 of the LED dimming driver 1. Adjusting the voltage or current input of the control port 9 of the LED dimming driver 1 corresponding to the output of the LED from the initial voltage to the highest voltage of the output terminal of the dimming driver 1 to change the voltage, thereby operating the current in each LED group The dimming curve is changed to achieve the purpose of dimming.

 At the same time, since a current limiting device is disposed in each LED lamp group (the size of the current limiting component can be determined by those skilled in the art), even if the LED dimming driver 1 outputs the highest voltage, the LED lamp group is at the rated working voltage. The work does not cause overcurrent damage due to the discreteness of the individual LED lights in the lamp group.

Claims

claims 1. An LED dimming driver, characterized by: including an electromagnetic interference filter circuit, a rectifier circuit, a power factor correction circuit, a high-frequency DC\DC step-down isolation conversion circuit, a PWM control circuit, an output voltage feedback control circuit, and start Voltage regulator, D/A conversion circuit, MCU chip, isolation optocoupler A and isolation optocoupler B; The electromagnetic interference filter circuit, rectifier circuit, power factor correction circuit, and high-frequency DC\DC step-down conversion circuit are connected in sequence. The output end of the high-frequency DC\DC step-down conversion circuit is the output end of the LED dimming driver. The input terminal of the power factor correction circuit is the input of the LED dimming driver. ¾; The input end of the PWM control circuit is connected to the output end of the isolation optocoupler A, and the output end is connected to the control end of the high-frequency DC\DC step-down isolation conversion circuit; The starting voltage regulator is connected to the MCU input end, the MCU output end is connected to the output voltage feedback control circuit through the D/A conversion circuit and then connected to the isolation optocoupler A input end; the MCU input end is connected to the isolation optocoupler B, isolation optocoupler B The input end is connected to the switch dimming port, and the output voltage feedback control circuit is simultaneously connected to the output end of the LED dimming driver; The upper limit of the control signal value of the LED dimming driver control port corresponds to the upper limit of the output voltage of the LED dimming driver output terminal, and the lower limit of the control signal value of the LED dimming driver control port corresponds to the output voltage of the LED dimming driver output terminal to drive the LED load lamp group. Starting voltage of operation. 2. The LED dimming driver according to claim 1, characterized in that: the control signal of the LED dimming driver control port is a standard dimming interface DC1-10V voltage, or the control signal of the LED dimming driver control port is The signal is a standard dimming interface DC4-20MA current. 3. The LED dimming driver according to claim 2, characterized in that: the upper limit of the output voltage of the output terminal of the LED dimming driver is 12 volts, the upper limit of the voltage signal value of the control port of the LED dimming driver is 10 volts, and the lower limit is 1 volt; or the upper limit of the output voltage of the LED dimming driver output terminal is 12 volts, the upper limit of the current signal value of the control port of the LED dimming driver is 20 mA, and the lower limit is 4 mA. 4. An LED light source system, including an LED dimming driver and an LED dimming driver connected in parallel. Several LED light groups at the driver output end are characterized by: The LED dimming driver includes an electromagnetic interference filter circuit, a rectifier circuit, a power factor correction circuit, a high-frequency DC\DC step-down isolation conversion circuit, a PWM control circuit, an output voltage feedback control circuit, a starting voltage regulator, and a D/A Conversion circuit, MCU chip, isolation optocoupler A and isolation optocoupler B; The electromagnetic interference filter circuit, rectifier circuit, power factor correction circuit, and high-frequency DC\DC step-down conversion circuit are connected in sequence. The output end of the high-frequency DC\DC step-down conversion circuit is the output end of the LED dimming driver. The input terminal of the power factor correction circuit is the input of the LED dimming driver. ¾; The input end of the PWM control circuit is connected to the output end of the isolation optocoupler A, and the output end is connected to the control end of the high-frequency DC\DC step-down isolation conversion circuit; The starting voltage regulator is connected to the MCU input end, the MCU output end is connected to the output voltage feedback control circuit through the D/A conversion circuit and then connected to the isolation optocoupler A input end; the MCU input end is connected to the isolation optocoupler B, isolation optocoupler B The input end is connected to the switch dimming port, and the output voltage feedback control circuit is simultaneously connected to the output end of the LED dimming driver; The upper limit of the control signal value of the LED dimming driver control port corresponds to the upper limit of the output voltage of the output terminal of the LED dimming driver, and the lower limit of the control signal value of the LED dimming driver control port corresponds to the output voltage of the output terminal of the LED dimming driver to drive the LED load lamp group. Starting voltage of operation; Each of the LED lamp groups includes a series-connected current limiting element and a plurality of LED lamps. 5. The LED light source system according to claim 4, characterized in that: the control signal of the LED dimming driver control port is a standard dimming interface DC1-10V voltage, or the control signal of the LED dimming driver control port It is the standard dimming interface DC4-20MA current. 6. The LED light source system according to claim 5, characterized in that: the upper limit of the output voltage of the LED dimming driver output terminal is 12 volts, the upper limit of the voltage signal value of the control port of the LED dimming driver is 10 volts, and the lower limit is 1 volt; or the upper limit of the output voltage of the LED dimming driver output terminal is 12 volts, the upper limit of the current signal value of the control port of the LED dimming driver is 20 mA, and the lower limit is 4 mA. 7. The LED light source system according to any one of claims 4 to 6, characterized in that: the current limiting element is a resistor.