Design Of Low Current Electronic Load In High Power Physical Load

Physical load consists of resistors,inductors and capacitors connected in series or in parallel.Their load values and load types cannot be modified at will.In view of it is too hard to make the small current physical load of the aviation generator load test,and the wiring resistance would change with the length of the wire due to the impedance change of end voltage and other shortcomings,this paper designs a small current electronic load device.The electronic load is controlled by power electronic devices.It can simulate various resistances and types of load.Compared with traditional physical load,the electronic load is small,light weight,continuous adjustable size,widely used in AC generator,switching power supply,battery and other equipment testing.This paper designs a small current electronic load device,which can be combined with physical load,using shunt method to complete the test of high-power power supply,and can test the small power supply separately.Firstly,it is introduced for the research status of electronic load at home and abroad,and the topology of the main circuit of small current electronic load is given.By analyzing the principle of four quadrant operation of voltage source PWM rectifier,the working principle of electronic load is given.The selection basis of main parameters in main circuit topology is discussed and the selection basis of inductance parameters is introduced emphatically.An improved starting scheme for single-phase AC electronic load is presented.Secondly,it is studied for the electronic load current loop control system.The paper focus on the analysis of the working principle of current indirect control system and direct current control system and the specific control process,gives the calculation method of linear load and nonlinear load current,analyzes the working principle of hysteresis comparison control bipolar modulation,and designs the hysteresis control strategy.Finally,the paper designs the hardware circuit,and builds the system simulation model in Matlab/Simulink environment.Under different conditions,the simulation results show that the design scheme can meet the design requirements,and the expected researchobjectives are completed.