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CN-116449757-B - Alternating current load design system based on DSP energy feedback

CN116449757BCN 116449757 BCN116449757 BCN 116449757BCN-116449757-B

Abstract

The invention discloses an alternating current load design system based on DSP energy feedback, which relates to the technical field of electric power and comprises an isolation voltage reduction module, a load simulation module, a DSP control module and a power feedback module, wherein the isolation voltage reduction module is used for reducing the input voltage of alternating current, the load simulation module is used for sampling the input current and the reduced input voltage and sending the sampled input current and the sampled input voltage to the DSP control module, the DSP control module is used for carrying out A/D conversion on the sampled input current and the sampled input voltage and outputting corresponding PWM and SPWM according to an adjustment algorithm, and the power feedback module is used for realizing control on steady-state current and power factor through PI adjustment according to the output PWM and SPWM.

Inventors

  • ZHANG HONGYI
  • PENG FEI

Assignees

  • 东南大学

Dates

Publication Date
20260505
Application Date
20230419

Claims (5)

  1. 1. An energy feedback type alternating current load design system based on a DSP, which is characterized by comprising: the isolation voltage reduction module is used for reducing the input voltage of the alternating current; The load simulation module is used for sampling the input current and the input voltage after the voltage reduction and sending the input current and the input voltage to the DSP control module; The load simulation module samples the input current and the input voltage after the voltage reduction as follows: firstly, sampling and calculating to obtain an effective value of input alternating current, so as to obtain a peak value of the input alternating current, dividing an instantaneous value V obtained by sampling by the peak value, calculating to obtain a voltage phase phi at the moment, adding an additional phase angle psi corresponding to a power factor required at the moment, and calculating to obtain an ideal current instantaneous value IREF under the load characteristic, so that the analog load characteristic can be controlled only by controlling the current instantaneous value to enable the current instantaneous value to be the same as the ideal current value IREF; in order to control the instantaneous value I to reach the ideal instantaneous value IREF, sampling the real current instantaneous value I at the moment, regulating and controlling the current instantaneous value I by using PI, and finally obtaining the ideal current instantaneous value IREF through the on-off of an H bridge; the DSP control module is used for carrying out A/D conversion on the sampled input current and input voltage and outputting corresponding PWM and SPWM according to an adjustment algorithm; And the power feedback module is used for controlling steady-state current and power factor by PI regulation by using a full-control inverter circuit according to the output PWM and SPWM, and finally obtaining the waveform results of rectification and energy feedback.
  2. 2. The DSP energy feedback based ac load design system of claim 1 wherein said load simulation module and power feedback module employ an H-bridge configuration and select high withstand voltage IRF640 to form an H-bridge circuit.
  3. 3. The system of claim 1, wherein when the ac input power is gradually accumulated in a large capacitor between the analog load circuit and the energy feedback current, the voltage across the capacitor is gradually increased to store the input energy, and when the energy accumulation is excessive, the capacitor cannot hold more energy, the power feedback module is controlled to operate to perform power energy feedback.
  4. 4. The system of claim 3, wherein the power feedback module samples a voltage VDC across the large capacitor, and when the VDC exceeds a threshold, the power feedback module generates SPWM to release capacitive energy.
  5. 5. The system of claim 1, wherein the PWM driving circuit uses a half-bridge driving chip LKS560, after RC filtering, the PWM driving circuit connects the input PWM to the LKS560 chip, uses a bootstrap circuit, selects 220pF capacitor to turn on the MOS transistor, uses IRF3710 with high withstand voltage, and outputs a pair of complementary PWM with enhanced load energy by inputting a pair of identical PWM waves to the LKS560 to control the power amplifier stage switch.

Description

Alternating current load design system based on DSP energy feedback Technical Field The invention relates to the technical field of electric power, in particular to an energy feedback type alternating current load design system based on a DSP. Background With the development of power electronics technology, the high-power alternating current power supply can be flexibly applied to various electric related fields such as power systems, motor driving and the like. For the safety performance test and aging of the power supply before delivery, as well as the service life, performance and maintenance of the power supply, the traditional switching load is gradually eliminated by the market due to the defects of poor flexibility, high cost and the like. However, the existing ac load design can flexibly change the load property according to the use requirement, but the problems of high heat energy loss and high heat dissipation cost caused by high voltage and high power are not negligible. The design based on the DSP energy feedback type alternating current load not only meets the requirement of simulating flexible and changeable load demands such as linear resistive load, nonlinear sensibility, capacitance and the like, but also can carry out active inversion on the rectified DC through SPWM generated by the DSP, thereby realizing the purpose of energy feedback, recycling the electric energy, solving the traditional load energy consumption problem and promoting the realization of a 'double carbon' strategic target in the industry. In addition, the amplitude staff of China is wide, the use of the high-voltage high-power supply is particularly important in both life and production and manufacturing industries of people, various compensation means are often adopted in the power system industry to reduce reactive power loss, the alternating current load can control constant current input while simulating different properties, and the power factor can be modified by the requirement to reduce the loss and the compensation cost, so that the application prospect is very good. Disclosure of Invention In order to solve the above-mentioned drawbacks in the background art, an objective of the present invention is to provide an energy-fed type ac load design system based on DSP. The invention can realize the aim by the following technical scheme that the energy-feedback alternating current load design system based on the DSP comprises: the isolation voltage reduction module is used for reducing the input voltage of the alternating current; The load simulation module is used for sampling the input current and the input voltage after the voltage reduction and sending the input current and the input voltage to the DSP control module; the DSP control module is used for carrying out A/D conversion on the sampled input current and input voltage and outputting corresponding PWM and SPWM according to an adjustment algorithm; And the power feedback module is used for controlling steady-state current and power factor by PI regulation by using a full-control inverter circuit according to the output PWM and SPWM, and finally obtaining the waveform results of rectification and energy feedback. Optionally, the load simulation module and the power feedback module adopt an H-bridge structure, and the IRF640 with high withstand voltage is selected to form an H-bridge circuit. Optionally, the load simulation module samples the input current and the input voltage after the step-down as follows: firstly, sampling and calculating to obtain effective value of input alternating current so as to obtain peak value of input alternating current, dividing instantaneous value V obtained by sampling by peak value and calculating to obtain voltage phase at that time The ideal current instantaneous value IREF under the load characteristic is calculated by adding the additional phase angle psi corresponding to the power factor required at the moment, so that the analog load characteristic can be controlled by only controlling the current instantaneous value to be the same as the ideal current value IREF. Optionally, in order to control the instantaneous value of I to reach the ideal instantaneous value IREF, the real current instantaneous value I at the moment is sampled, PI is used for regulating and controlling the current instantaneous value I, and finally the ideal current instantaneous value IREF is obtained through the on-off of the H bridge. Optionally, when the ac input power is gradually accumulated in the large capacitor between the analog load circuit and the energy feedback current, the voltage at two ends of the capacitor is gradually increased to store the input energy, and when the energy accumulation is excessive, the capacitor cannot accommodate more energy, the power feedback module is controlled to work, and power energy feedback is performed. Optionally, the power feedback module samples voltage VDC at two ends of the large capacitor, and