Abstract: In order to improve the control scheme of PSFB ( Phase-Shifting Full Bridge) converter and obtain better control indicators, a fuzzy PID( Proportional Integral Derivative) control method is proposed based on IGWO ( Improved Grey Wolf Algorithm) optimization. The fractional impedance components in the PSFB converter circuit have non integer order characteristics. Using fractional calculus theory and state space averaging method, the fractional order phase-shifting full bridge converter is modeled and optimized for control analysis. Adaptive inertia weight and Euclidean distance method are used to optimize the global characteristics and convergence of GWO, and then the quantization factor of the fuzzy controller calculated to optimize the control effect. The IGWO optimized fuzzy PID control scheme is used in PSFB converters to compare with two traditional schemes, and a 50 W prototype is designed to verify the effectiveness of the control strategy. The simulation results show that the fuzzy PID control optimized by IGWO reduces the time savings, overshoot, and steady-state error 98. 18% , 99. 63% and 44. 44% , and 66. 67% , 33. 33% , and 89. 13% , respectively, compared to the traditional two PID control methods. The experimental results of fuzzy PI ( Proportional Integral ) control simulation verification based on hardware IGWO optimization of TMS320F28034 show that it has better control accuracy and stronger anti-interference ability compared to fuzzy PID.

Key words: grey wolf optimization algorithm, fractional phase-shifting full-bridge converter, fuzzy contro, euclidean distance method