PV fed BLDC motor using zeta converter with minimized torque ripple for water pumping

摘要

Solar energy is an important renewable resource which is abundant in nature and free of running cost. The extracted solar energy can be used to drive motors for water pumping application. Motors used for this application are DC motors, induction motors or BLDC motors of which BLDC motors are more advantageous. BLDC motor is fed from a voltage source inverter which has a dc link capacitor at the front end. The life time of dc link capacitor is affected by its operating temperature. Also it adds to the cost of BLDC motor drive. The elimination of dc link capacitor reduces the cost and bulkiness of motor but it results torque ripple to arise at the output of motor. Thus to minimize torque ripple, a new method is proposed where the dc link capacitor is replaced by a ceramic capacitor and a switch. It reduces the torque ripple which arises due to the elimination of electrolytic capacitor and the compensation capacitor is only around 3% of original dc link capacitor.