AbstractsEngineering

With the recent inventions and advancements in high flux density and high performance permanent magnets like neodymium boron iron and samarium cobalt Permanent Magnet Synchronous Motor PMSM came into existence Permanent magnet PM motors became very popular due to their simple structure efficiency robustness and high torque size or weight ratio One of the most popular control methods of three phase motor drive systems well developed during the last decade is Field Oriented Control FOC usually realized with a digital Pulse Width Modulation PWM controller in rotating direct quadrature coordinate space PMSM is widely used in industrial servo applications due to its high performance characteristics However torque pulsations are present in PMSM due to inverter switching cogging flux harmonics and errors in current measurement These torque pulsations result in periodic speed ripples and torque ripples which restrict its wide acceptance as servo drives For applications that require precise tracking the machine should be free of torque ripples Field oriented vector controlled PMSM drive affords improved dynamic response and minimum torque ripples and requires a constant switching frequency for working In order to minimize the torque ripples many methods are proposed in literature newline%%%appendix p165-192.