DTC based BLDC Motor Controlled Centrifugal Pump Fed by PI-BFO Tuning Strategy for Buck-Boost Converter in Solar PV Array Water Pumping System

In this paper, the performance of the directly coupled solar photovoltaic water pumping system has been investigated at different conditions of solar radiation, ambient temperature and speed. A BLDC motor is employed to drive a centrifugal pump coupled to its shaft due to merits of high efficiency and compact size of this drive. This system utilizes a Buck-Boost converter as an interface DC-DC converter between the solar photovoltaic array and the inverter of BLDC motor drive. The application of direct torque control strategy to BLDC drives has been investigated. In this control method for BLDC drive, direct control of stator flux and electromagnetic torque, and attainment rapid torque response and the high efficiency is possible by choosing the efficient modes of switching inverter to confine flux and torque error in a proper hysteresis band. MATLAB software is used to analysis, design and control of this system and represent the performance of transient and steady state response of SPV array powered Buck-Boost converter fed BLDC driven water pumping system. Simulated results are displayed, and it is shown that, compared with conventional hysteresis and PWM current control, the BFO-PI strategy results in reduced current and torque ripple, robust performance, faster dynamic response and lower steady state error under different mode operation.