Design Of Energy-feeding DC Electronic Load Control System

With the continuous development of new energy technology,the types of power supply equipment are also being introduced,and the demand for power supply types is also expanding.Power failure will cause inconvenience to residents’ lives,and even life safety.Therefore,the power supply equipment needs to be tested with no load or full load before leaving the factory.In the early days,static resistance was generally used to test the power supply.This method has many disadvantages.For example,the load type is limited and the resistance value cannot be changed.The resistance will consume electricity and generate heat.This scheme is relatively primitive and backward.At present,the power supply type is constantly updated and cannot meet its test requirements.Therefore,the electronic load came into being.In this project,the energy-feeding electronic load is selected.The main purpose is to test the 36 V daily DC power supply,and the current ripple is less than 3%.The measured DC power supply has the characteristics of high current and low voltage.In order to achieve the goal of energy feedback to the grid,the power supply under test is first boosted to 400 V,and the energy-feeding DC electronic load needs to be boosted.It has a three-level topology structure.First of all,this topic will describe its topology in detail and reveal its working principle;mainly introduce the boost link,inverter link,energy feedback and other links to realize grid-connected current unit power factor grid connection.1.Analyze the principle of electronic load,choose between power supply type and current source type,design the overall scheme of the system,and give key technology and quality requirements.2.Analyze the structure and design process of the DC/DC converter.The DC/DC booster is composed of two-stage circuits,which are the Boost circuit and the phase-shifting full-bridge circuit.The boost circuit adopts the PI strategy,the main purpose is to make the output current of the power supply under test quickly follow the command current,and then set the PI parameters to realize the function of the boost circuit to simulate various load working modes.3.Starting from the inverter link of the energy-fed electronic load,analyze the working principle of the three-phase grid-connected inverter,and select the current as the control variable.Set a complete grid-connected control strategy,use the control variable method to set the parameters,and complete the grid-connected goal of unity power factor of the grid-connected current.4.Build a simulation in Matlab/Simulink to test the above strategies;conduct experiments on the dSPACE platform;analyze the data and record and verify the current waveform;finally,the above control objectives have been achieved.There are(80)figures,(5)tables,and(53)references in the text.