Supplying a brushless dc motor by z-source PV power inverter with FL-IC MPPT

Abstract

This paper describes the optimal operation performance of a brushless dc motor (BLDC), fed by a z-source inverter accompanying with photovoltaic (PV) system, drives a water pumping system. Albeit the conventional PV water pumping systems, including a two stages converter, the proposed system employs a Z-source inverter (ZSI) to extract the Maximum Power of PV array and supply the BLDC motor. Utilizing the Z-source inverter provides some advantages such as high efficiency and low cost. In order to achieve an accurate Maximum Power Point Tracking (MPPT) of the PV array, fuzzy logic controller is applied to accomplish an appropriate variable step size in incremental conductance method. Due to PV power variation, the BLDC motor should be driven with variable reference speed. For accessing better dynamic response for speed variations of the BLDC motor, Particle Swarm Optimization (PSO) has been used to regulate the PID parameter of speed controller. Reducing the torque ripple and high current control capability of BLDC motor, hysteresis current control with current shaping is used to drive the BLDC motor.