Research And Design Of Power Inductance Saturation Parameter Measurement System

In recent years,the application of power electronic technology in power system has become more and more extensive and in-depth.In many types of power electronic equipment,power supply,as one of them,has higher and higher requirements for its performance and function.As the most important component of switching power supply-power inductor,its electrical parameter characteristics largely determine the efficiency and reliability of the whole power supply.Therefore,it is very important to test the electrical parameters of the power inductor,especially the saturation parameters of the power inductor,and make application evaluation before the production of the switching power supply.The specific research contents of this dissertation are as follows:(1)The characteristics of magnetic materials are analyzed,and the important saturation parameters characterizing the power inductance capacity are obtained.This dissertation studies how to obtain the electrical parameters characterizing the power inductor capacity through the inductance conduction current curve,and simulates the power inductor current curve through Saber software.The simulation results verify that the power inductor is saturated,and the main factors affecting the power inductor capacity are obtained.In this dissertation,the wavelet algorithm is used to select and extract the characteristic quantity of the power inductor current curve,and the waveform recognition method is used to obtain the electrical parameters of the power inductor,especially the saturated current parameters of the power inductor.(2)The design and implementation of the hardware circuit system for measuring the saturation parameter of power inductor.In order to realize high-speed sampling of current data,the system adopts a hardware scheme combining FPGA and high-speed ADC sampling.The circuit mainly includes FPGA circuit,auxiliary power supply circuit,H-bridge drive circuit,optocoupler isolation and logic protection circuit,high-speed ADC sampling circuit,etc.Among them,FPGA circuit includes FPGA peripheral circuit and internal control logic circuit.The peripheral circuit mainly contains the smallest system circuit that can realize FPGA operation,such as RAM,ROM,JTAG,etc.The internal control logic circuit includes custom IP circuit and Nios II soft core circuit that can realize high-speed sampling(3)Design and implementation of software system based on Ucos II operating system.In the Nios II soft core system in FPGA,a software system based on the Ucos II operating system is built.The system has three main tasks,including high-speed ADC data sampling,current curve initial filtering algorithm,wavelet decomposition and reconstruction,and Usart serial screen display.(4)The system test experimental environment is built,including the hardware circuit operation test,the inductance saturation judgment algorithm test and the overall system function test.The test results verify that the system described in this paper has achieved the established technical objectives.