FPGA Realization of an Adaptive Fuzzy Controller for PMLSM Drive

This paper presents a hardware realization of an adaptive fuzzy controller (AFC) for a permanent-magnet linear synchronous motor (PMLSM) drive system based on the field-programmable gate-array (FPGA) technology. First, a mathematics model of the PMLSM drive is defined; then, to increase the performance of the PMLSM drive system, an AFC constructed by a fuzzy basis function and a parameter-adjustable mechanism is applied to the position-control loop of the PMLSM drive system to cope with the effect of the system dynamic uncertainty and the external load. A point-to-point (PTP) motion trajectory designed with the trapezoidal velocity profile is considered to smooth the move of the PMLSM at the start and stop conditions. Second, a finite-state machine (FSM) joined by a multiplier, an adder, a lookup table, and some comparators and registers is presented to model the overall AFC, and a VHSIC hardware description language is adopted to describe the circuit of the FSM. In addition, a Nios II embedded processor is used to implement the function of the PTP motion-trajectory algorithm by software. Finally, an experimental system is established to verify the effectiveness of the proposed FPGA-based AFC and the PTP motion-control system, and some experimental results are confirmed theoretically.