Application Research Of Three-Phase PWM Rectifier In Enengy-feedback Electronic Load

With the development of power electronics technology,various power supply have emerged in our field of vision,bringing convenience to our lives.As we all know,power products need to be tested various characteristics and indicators in the production process.Traditional test methods have many drawbacks,such as single load characteristics,inconvenient parameter modification,low load accuracy,and high power test energy waste.The emergence of electronic load overcomes the shortcomings of traditional test methods,and has many advantages such as high load accuracy,flexibility,green energy saving and intelligence.In this paper,a three-phase enengy-feedback electronic load is studied for the test of three-phase power.In order to ensure the system integrity of the enengy-feedback electronic load,the overall scheme and working principle analysis of the whole system are given.However,the work of this paper is mainly concentrated on the front load simulation side.There are two key problems to be solved,namely the solution of the load model current command and the tracking control of the output current of the tested power supply.Main tasks as follows:Firstly,the principle of load simulation and energy feedback are analyzed.The main circuit parameters are designed for the design indicators.A mathematical model of the three-phase PWM rectifier in the dq coordinate system is established for the controlled object,and decoupling is realized.The direct current control based on SVPWM is chosen as the control strategy of this paper.The principle and implementation method of SVPWM algorithm are analyzed,and the current closed-loop regulator is designed.Secondly,the load model and its current command generation are studied.A recursive algorithm which is easy to implement digitally is used to complete the current command generation of linear load and nonlinear load in dq coordinate system.Then the load simulation is given.The specific implementation of the hardware and software of the side control system,the hardware part includes the design of the drive circuit,the auxiliary power supply circuit,and the overcurrent protection circuit.The software part gives the design idea and flow chart of the main program and interrupt service program.The specific implementation scheme of the hardware and software of the control system is given.The hardware part mainly includes the design of the drive circuit,the auxiliary power supply circuit and the overcurrent protection circuit.The software part gives the design idea of the main program and interrupt service program and the implementation flow chart.Finally,a system simulation model was built in MATLAB/Simulink to verify the correctness of theoretical analysis and design.A 20 kW three-phase electronic load test prototype based on STM32F103VCT6 control was completed,and the experimental study of constant impedance load was completed.Some experimental results were given.There are 74 figures,9 tables and 61 references in this paper.