Rearch On Digital Switching Power Supply Controller Based On Fuzzy Sliding Mode Control

Users have higher and higher demands for performance of power equipment with the rapid development of power electronics technology,so digital power is used more and digital control methods had a major impact on the performance of switching power supply.In this paper,the sliding mode variable structure digital controller achieve control of switching power supply and solve control performance of switching power supply.Quasi-linear modeling method is used to model the phase-shift full bridge high frequency switching power supply in order to overcome the disadvantages of small signal model by state space averaging method have limitations to work in a large parameter range changes.On the basis of this model,a fuzzy sliding mode variable structure controller of the high frequency switching powrer supply is designed by selecting linear switching function and control rate based on variable rate reaching law.This controller combines the traditional fuzzy control and variable structure control,simplifies the input fuzzy controller,softens the control signal,and reduces the chattering of general variable structure control at the same time.It has a better effect on dynamic response and mutation of system conditions than traditional power supply controller.According to the structure and parameters of the main circuit,determinomg the fuzzy sliding controller structure and parameters through matlab algorithm simulations of the response performance when various switching power supply system parameters change,and optimize the best fuzzy rules and variable structure parameters.Digital controller has been designed by FPGA,including the digital filter,PWM wave generated modules,power protection module,MicroBlaze soft-core processor,etc.A digital controller has been composed,and have a good effect of output voltage.And the proximal and distal interpersonal interaction have been designed,proximal have LCD display based on MicroBlaze and keyboard controller,a host computer interface based on Labview has been designed on remote to achieve user purpose of real-time monitoring of the running status of switching power supply.Experiments and simulations results validate the designed controller has better performance and flexibility than conventional controllers.