A Research On Control Method Of Single-phase Energy-fed AC Electronic Load

With the development of industrial society,reliable power supply system plays a key role in ensuring the normal operation of electrical equipment and automation equipment in industrial enterprises.The power supply device with high reliability is the key device to improve the operation stability of power supply equipment in industry.In order to test the reliability of standby power supply,it is necessary to carry out a series of on-load tests such as aging test and overload test before leaving the factory.The traditional load forms are usually composed of energy-consuming devices such as resistors,capacitors and inductances,which are inconvenient to adjust and consume energy.As a new type of power supply testing equipment,power electronic load equipment has the advantages of simple structure,convenient adjustment and low-energy consumption.Above this,how to develop AC electronic load which can accurately simulate the expected load characteristics and feed the energy with unit power factor back to the power grid is the key problem for the electronic load as a power supply testing device.Based on this issue,focusing on the single-phase energy-fed AC electronic load,this paper studies its development status,working mode and operation principle.Around the basic principle of electronic load,the current control method is studied for the circuit of its front load analog side and the rear energy feedback side.This paper presents a composite control strategy based on deadbeat control and repetitive control.Deadbeat control with current compensation can improve the rapidity of the controller,and repetitive control can achieve better steady-state performance of the system.Based on the simulation experiment of MATLAB/Simulink,the designed composite control method is simulated and validated.Finally,a 3 kW hardware experiment platform is built.Through hardware design,debugging and software implementation,the designed electronic load circuit topology and control method are verified by hardware experiment.The experimental results show that the strategy can make the dynamic response fast and the steady-state error small and it can effectively realize the functions of load-analog and grid-connection.