1kW直流电子负载的设计与仿真

Design and simulation of 1kW DC electronic load

直流电子负载是一种代替传统的能耗型负载设备,由于能馈型电子负载本身不存在电阻等耗能型器件,而是通过电力电子开关电路将测试电能回馈至电网或者是被测设备的输入端。为了满足实验室电源测试的需要,设计了一种1kW直流电子负载。该直流电子负载是基于Boost升压电路和单相逆变电路,前级实现负载模拟,后级完成电能回馈。建立了Boost电路的小信号模型,得到输入电流对占空比的传递函数,最后设计相应的比例积分(PI)控制器,利用Matlab搭建仿真模型,验证了理论推导的正确性。

The DC electronic load is a kind of equipment to replace the traditional energy-consuming load.Because the energy-feedback electronic load itself does not have energy- consuming devices such as resistors,it feeds back the test energy to the power grid or the input of the equipment under test through the power electronic switching circuit.In order to meet the needs of laboratory power supply testing,a1kW DC electronic load is designed.The DC electronic load is based on the Boost circuit and single-phase inverter circuit.The front stage realizes load simulation,and the back stage completes power feedback.The small signal model of the boost circuit is established,the transfer function of the input current to the duty cycle is obtained,and the corresponding proportional integral(PI) controller is designed.The simulation model is built by Matlab to verify the correctness of the theoretical derivation.