CN109548239B - LED lamp power supply control device with virtual synchronous machine response mechanism - Google Patents

Abstract

The invention discloses an LED lamp power control device with a virtual synchronous machine response mechanism. The device receives an ambient light intensity signal measured by a light intensity sensor, a power grid and LED lamp power related signals measured by a voltage sensor, and an upper-layer energy dispatching system transmission. Based on the wireless dispatching instructions, make a comprehensive judgment based on the information, and generate the instruction signals for adjusting the power supply of the LED lights and send them to the PFC module and the DC/DC module for converting the AC power of the grid into the DC power supply for the LED lights. The invention can improve the working efficiency of the LED power supply and reduce unnecessary energy consumption; at the same time, it can actively participate in the grid-side response to improve the stability of the grid; it can also realize modern digital intelligent dispatching and improve the accuracy and efficiency of intelligent dispatching.

Description

A LED lamp power control device with a virtual synchronous machine response mechanism

technical field

The invention relates to an LED lamp power supply control technology, in particular to an LED lamp power supply control device with a virtual synchronization machine response mechanism.

Background technique

In recent years, LED lamps have been widely promoted and applied due to their low loss, long life, and green energy saving. As the "heart" of LED lamps, the driving power has become an important part of the promotion and development of LED lighting. With the rapid development of science and technology, LED power supply has also developed rapidly. At this stage, there are mainly constant current and regulated power supply, which only guarantees the basic power supply of LED power supply, and does not involve actively participating in smart grid frequency regulation and other needs, so it cannot respond to the power grid. and the intelligent requirements of users.

SUMMARY OF THE INVENTION

Object of the invention: In view of the above problems of the prior art, the present invention provides an LED lamp power control device with a virtual synchronous machine response mechanism.

Technical scheme: The LED lamp power control device of the present invention includes a voltage sensor, a light intensity sensor, a wireless transmission module and a DSP controller; the voltage sensor measures the grid side voltage, the grid side input current, the output power factor correction PFC module output DC voltage and The current of the LED light is forwarded to the DSP controller; the PFC module converts the AC power into the DC power of the DC/DC module, and the DC/DC module provides power for the LED light; the light intensity sensor measures the ambient light intensity and forwards it to the DSP The controller; the wireless transmission module forwards the wireless dispatching instructions of the upper energy dispatching system to the DSP controller; the DSP controller is configured to: calculate the grid frequency based on the grid side voltage, and generate a first signal for adjusting the brightness of the LED lights based on the grid frequency and the first indication value; generate a second signal and a second indication value for adjusting the brightness of the LED light based on the ambient light intensity; measure the grid side voltage, grid side input current, output power factor correction based on the voltage sensor The DC voltage output by the PFC module and the LED The lamp current parses the wireless scheduling instruction, and generates a third signal and a third indication value for adjusting the brightness of the LED lamp; based on the first, second and third signals for adjusting the brightness of the LED lamp and the respective indication values, a first control instruction is generated for The DC/DC modules are controlled.

Further, the DSP controller also generates a second control command according to the grid side voltage, the grid side input current and the DC voltage output by the PFC module, for controlling the PFC module.

Further, the DSP controller includes an analog-to-digital converter ADC, a serial port port and a virtual synchronous machine response mechanism control module; the ADC receives the analog signal of the measurement result forwarded by the voltage sensor and the light intensity sensor, and converts it into a corresponding digital signal; It is used to realize the communication between the wireless transmission module and the virtual synchronous machine response mechanism control circuit; the virtual synchronous machine response mechanism control module includes a phase-locked loop PLL component, a proportional component, an inverse proportional component, an analytical instruction component, and an instruction priority selection. The component, the PFC module control component and the DC/DC module control component; the PLL component calculates the grid frequency and the grid-related sinusoidal signal based on the digital signal of the grid side voltage; the inverse proportional component generates a first signal and a first signal for adjusting the brightness of the LED lamp based on the grid frequency Indication value; the proportional component generates a second signal and a second indication value for adjusting the brightness of the LED light based on the digital signal of the ambient light intensity; the analytical command component combines the grid-side voltage, grid-side input current, the DC voltage output by the PFC module and the LED light current. Parse the wireless scheduling command to generate a third signal and a third indication value for adjusting the brightness of the LED light; the command priority selection component generates the reference current of the LED light based on the first, second and third signals for adjusting the brightness of the LED light; DC/DC The module control component generates the first control command based on the LED lamp reference current; the PFC module control component generates the first control command based on the grid side voltage, the grid side input current and the digital signal of the DC voltage output by the PFC module and the sinusoidal signal. 2. Control instructions.

Further, each component and its function in the virtual synchronous machine response mechanism control module are realized by programming the programmable circuit.

Further, the first and second control instructions are PWM pulse signals used to control the power devices in the PFC module and the DC/DC module.

Further, the third indication value is always higher than the first and second indication values; the first indication value increases with the increase of the grid frequency; the second indication value increases with the increase of the ambient light intensity.

Beneficial effects: Compared with the prior art, the LED lamp power control device and method of the present invention has the following advantages: 1. It can realize light self-adaptation, thereby realizing the purpose of energy saving; 2. It can actively respond to the frequency of the power grid and improve the stability of the power grid; 3. The wireless transmission module is used to upload signals and receive instructions from the dispatching system, improve the accuracy and efficiency of intelligent dispatching, and enable remote control of the LED lamp power supply; 4. Through the priority setting, the continuous power adjustment can be optimized. 5. The response mechanism and priority setting of the virtual synchronization machine are only implemented by software, without changing the original hardware circuit, and the cost is low.

Description of drawings

Fig. 1 is a signal schematic diagram of supplying power to an LED through a power grid in the prior art;

Fig. 2 is the structure diagram of the LED lamp power supply control device of the present invention;

Fig. 3 is the control principle diagram of the virtual synchronous machine response mechanism in the LED lamp power supply control device of the present invention;

Fig. 4 is the working principle diagram of the phase-locked loop assembly of the present invention;

Fig. 5 is the working principle diagram of the PFC module control assembly of the present invention;

FIG. 6 is a working principle diagram of the DC/DC module control assembly of the present invention.

in:

V _lig represents the voltage signal after light intensity conversion;

V _in represents the grid side voltage signal;

I _in represents the input current signal on the grid side;

V _dc represents the DC voltage signal output by the PFC;

I _o represents the current signal of the LED lamp;

V _dc* represents the output DC voltage reference signal;

I _in* represents the input current command signal on the grid side;

I _o* represents the current command signal of the LED lamp;

ωs represents the angular frequency of the grid-side voltage.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 1, the current LED lamp power supply is generally powered by the AC power supply of the power grid. After the totem pole output power factor correction (Totem Pole PFC) module, the DC power supply of the DC/DC module is obtained, and then the DC/DC module converts it into Appropriate voltage and current are used to power LED lights.

In the present invention, in order to effectively control the voltage and current of the LED lamp power supply, it is necessary to collect V _in , I _in , V _dc and I _o . Among them, V _in and V _dc can be directly collected by the voltage sensor, and I _in and I _o can be obtained by collecting the voltage on the corresponding load through the voltage sensor and then calculated by Ohm's law.

As shown in Figure 2, the LED lamp power control device of the present invention includes a voltage sensor, a light intensity sensor, a wireless transmission module and a DSP controller. The voltage sensor is used to collect V _in , I _in , V _dc and I _o , and convert them into low-voltage signals and send them to the DSP controller. The light intensity sensor is used to measure the light intensity of ambient light, and convert the measured light intensity into a low voltage signal and send it to the DSP controller for processing. The wireless transmission module is used to enable the DSP controller to receive the wireless scheduling instructions transmitted by the upper-layer energy scheduling system through the serial port, so as to parse the instruction information through the software protocol. At the same time, the wireless transmission module can upload the energy scheduling response information of the DSP controller and the operation information of the LED power supply, which is convenient for the upper-level energy scheduling system to comprehensively analyze and give instructions. The DSP controller makes a comprehensive analysis and judgment based on the low-voltage signal sent by the voltage sensor and the light intensity sensor and the wireless scheduling instruction transmitted by the wireless transmission module, and generates PWM signals for controlling the PFC module and the DC/DC module respectively, so as to control the PFC module through the PWM signal. And power devices (eg, GaN HEMT driver) in the DC/DC module, so as to control the power supply of the LED lamp to realize the adjustment of the brightness of the LED lamp.

As shown in Figure 3, the DSP controller includes an analog-to-digital converter ADC, a phase-locked loop PLL component, a PFC module control component, a proportional component, an inverse proportional component, an analytical command component, a command priority selection component, and a DC-DC control component. Among them, the ADC receives V _lig , V _in , I _in , V _dc and I _o , converts them into digital signals, and then outputs them to other components in the DSP controller. For example, _Vin is input to the PLL component to calculate the grid frequency ωs and outputs the grid frequency signal ωs to the inverse proportional component. The inverse proportional component outputs a first adjustment signal for adjusting the brightness of the LED light and a corresponding first indication value based on the grid frequency ωs, and the larger the value of ωs, the larger the first indication value (meaning that the priority of the first adjustment signal is higher) , otherwise the first indication value is lower. V _lig is output to the proportional component, and the proportional component outputs a second adjustment signal for adjusting the brightness of the LED light based on V _lig and the corresponding second indication value, and the stronger the intensity of the ambient light corresponding to V _lig , the lower the second indication value ( means the lower priority of the second conditioning signal). In addition, the wireless dispatching command from the upper-layer energy dispatching system is received by the serial port of the DSP controller through the wireless transmission module and then sent to the parsing instruction component. and the corresponding third indicated value. The command priority selection component receives the first, second and third adjustment signals for adjusting the brightness of the LED lights and their corresponding indicated values, compares the magnitudes of the indicated values, and outputs the LED light reference current I _o according to the adjustment signal corresponding to the maximum indicated value _* To the DC/DC module control module, the signal generated by the DC/DC module control module is used to control the DC/DC module in Figure 1. In addition, the PLL component also outputs the sinusoidal signal sinθ to the PFC module control component. The PFC module control component generates control signals for controlling the Totem-Pole PFC module of FIG. 1 based on the sinusoidal signal and _Vdc , _Iin , and _Vin obtained from the ADC.

In particular, in general, the third indication value (corresponding to the wireless dispatch instruction) may be set to be always higher than the second indication value (corresponding to the ambient light intensity) and the first indication value (corresponding to the grid frequency). The first indication value depends on the magnitude of ωs, and the second indication value depends on the magnitude of V _lig . The indicated value of the third instruction may be set as a constant. By setting in this way, the flexible control of the LED power supply can be realized as required, that is, when the grid frequency is relatively stable and no wireless scheduling command is received, the LED brightness is preferentially adjusted according to the change of the ambient light intensity (for example, in the ambient light When it is strong, reduce the brightness of the LED light, otherwise increase the brightness of the LED light); when the grid frequency deviates greatly from the rated frequency, the change of the grid frequency is given priority; and when the wireless scheduling command is received, the scheduling command is given priority.

As shown in Figure 4, the PLL component in the DSP controller includes four sub-modules: second-order generalized integration (SOGI), PARK transformation, LPF filtering, and voltage-controlled oscillator (VCO). Second-order generalized integration (SOGI) mainly converts the single-phase voltage signal Uin into two mutually perpendicular αβ coordinate signals, of which the α coordinate signal is kept in the same phase as the original Uin; PARK transformation converts the αβ coordinate signal into a rotation with the synchronous coordinate axis Two mutually perpendicular dq coordinate signals; the q-axis signal is filtered by the LPF filter to filter out the high-frequency signal, and its output only retains the DC component that reflects the voltage synchronization signal on the grid side; the VCO sub-module is connected to the DC component, and the proportional link is used. After outputting the frequency of the power grid, the virtual synchronous machine response mechanism control module gives the reference current for the power supply of the LED lamp that automatically adjusts the brightness according to the frequency; in addition, after the frequency of the output power grid passes through the integral link, the grid-side voltage phase tracking will be realized, and finally After a simple trigonometric function calculation, the sine signal sinθ used for PFC control is output to the PFC module control component, and the cosine signal cosθ used for PARK conversion is generated.

The PFC module control component is used to control the switch of the power device in the PFC module, so as to realize the voltage stability of the DC side, that is, to realize the power balance between the load side and the grid side. As shown in Figure 5, the PFC module control component includes two links: voltage control and current control. The voltage control is the outer loop, and the current control is the inner loop. The control speed of the inner loop is faster than that of the outer loop. The voltage loop consists of the DC voltage U _dc and the set reference value U _dc* difference comparison link and PI control link, the output of which is the amplitude of the current loop reference signal; the voltage loop output and the software phase-locked loop output The product of the sine signal is composed of The input reference signal I _in* of the current loop, then the difference between I _in and I _in* is made, and input to the PR control link, and finally the PR control link outputs the duty cycle signal to the PWM module, and the PWM module outputs the PWM pulse signal to control the PFC module. power devices in .

As shown in Figure 6, after the DSP controller receives the I _o* from the virtual synchronous machine response mechanism control module, the I _o* and the actual measured value I _o of the LED lamp current form a difference comparison link, and then the output is accounted for through the PI control link. Then the PWM module converts the duty cycle command into a PWM pulse signal of the DC/DC module that provides DC power for the LED lamp, controls the on-off of the power device, and finally realizes the closed-loop control of the brightness of the LED lamp.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the technical principle of the present invention, several improvements and modifications can also be made. These improvements and modifications It should also be regarded as the protection scope of the present invention.

Claims (4)

1. an LED lamp power supply control device, is characterized in that, comprises voltage sensor, light intensity sensor, wireless transmission module and DSP controller; The voltage sensor measures the grid side voltage, grid side input current, output power factor correction PFC module output DC voltage and LED lamp current, and forwards it to the DSP controller; wherein, the PFC module converts AC power into DC/DC module DC power , DC/DC module provides power for LED lights; The light intensity sensor measures the ambient light intensity and forwards it to the DSP controller; The wireless transmission module forwards the wireless scheduling instructions of the upper energy scheduling system to the DSP controller; The DSP controller is configured to: calculate the grid frequency based on the grid side voltage, and generate a first signal and a first indication value for adjusting the brightness of the LED lamp based on the grid frequency; and generate a second signal and a first indication value for adjusting the brightness of the LED lamp based on the ambient light intensity. Two indication values; based on the voltage sensor to measure the grid side voltage, grid side input current, output power factor correction PFC module output DC voltage and LED lamp current to analyze the wireless scheduling command, and generate a third signal and a third indicator value to adjust the brightness of the LED lamp ; Generate a first control command based on the first, second and third signals for adjusting the brightness of the LED lights and the respective indicated values, for controlling the DC/DC module; The DSP controller also generates a second control command according to the grid side voltage, the grid side input current and the DC voltage output by the PFC module, for controlling the PFC module; The DSP controller includes an analog-to-digital converter ADC, a serial port and a virtual synchronous machine response mechanism control module; The ADC receives the analog signal of the measurement results forwarded by the voltage sensor and the light intensity sensor, and converts it into a corresponding digital signal; The serial port is used to realize the communication between the wireless transmission module and the virtual synchronization machine response mechanism control module; The virtual synchronous machine response mechanism control module includes a phase-locked loop PLL component, a proportional component, an inverse proportional component, an analytical command component, a command priority selection component, a PFC module control component and a DC/DC module control component; The PLL component calculates the grid frequency and the grid-related sinusoidal signal based on the digital signal of the grid-side voltage; The inverse proportional component generates a first signal and a first indication value for adjusting the brightness of the LED light based on the grid frequency; The proportional component generates a second signal and a second indication value for adjusting the brightness of the LED light based on the digital signal of the ambient light intensity; The parsing command component parses the wireless scheduling command in combination with the grid side voltage, the grid side input current, the DC voltage output by the PFC module and the LED lamp current to generate a third signal and a third indication value for adjusting the brightness of the LED lamp; The instruction priority selection component generates the LED lamp reference current based on the magnitude of the first, second and third signals for adjusting the brightness of the LED lamp and the respective indicated values; The DC/DC module control component generates the first control command based on the LED lamp reference current; The PFC module control assembly generates the second control command based on the digital signal of the grid side voltage, the grid side input current and the DC voltage output by the PFC module and the sinusoidal signal. 2 . The LED lamp power control device according to claim 1 , wherein each component and its function in the virtual synchronous machine response mechanism control module are realized by programming a programmable circuit. 3 . 3 . The LED lamp power supply control device according to claim 1 , wherein the first and second control commands are PWM pulse signals for respectively controlling the power devices in the PFC module and the DC/DC module. 4 . 4. The LED lamp power control device according to claim 1, wherein the third indication value is always higher than the first and second indication values; the first indication value increases with the increase of the grid frequency; The second indication value increases as the ambient light intensity increases.

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