Abstract:In the finite set model predictive control of permanent magnet synchronous motors,there is no pulse width modulation link,and the optimal voltage vector directly acts on the inverter,the switching frequency is high.To reduce switching frequency,in the predictive current control system of permanent magnet synchronous motor model,a switching frequency control term with adaptive weight coefficient adjustment is introduced in the cost function.Firstly, establish a predictive current control model and analyze the impact of operating conditions and control cycles on switch frequency.Secondly,the switch frequency control term is introduced into the cost function,and the influence of the weight coefficients of the switch frequency control term on the switch frequency and motor control performance is analyzed.Then,based on fuzzy control theory,a model predictive current control system with adaptive adjustment of weight coefficients is designed.By detecting the control error values of stator current and reference current as the input of fuzzy control,and the switch term weight coefficient as the fuzzy output,the adaptive adjustment of the switch term weight coefficient is achieved.The simulation results show that compared to fixed weight coefficient control,the fuzzy adaptive switch term weight coefficient control method reduces the switching frequency by about 1.5 kHz when the current harmonic increases by 0.36%at a speed of 500 r/min,and by about 0.8 kHz at a speed of 2000 r/min.