Power Factor Improvement and Speed Control of SRM Drive Closed Loop

Abstract

This concept deals with an input power quality improvement in an Asymmetric Converter based switched reluctance motor (SRM) drive at ac mains using a Reactor circuit. Normally an asymmetric converter is used as a power converter for SRM drive. Conventionally three phase ac mains fed bridge rectifier is used as a dc source to feed this power converter which produces high content of harmonics at ac mains with a very low power factor. The proposed circuits with an asymmetric converter fed SRM drive enhance the power factor at ac mains with low current harmonics. By this method we can get almost constant dc link voltage which can be applied to the converter. The proposed SRM drive is modeled and its. The performance of the reactor circuit topology is compared with a conventional SRM drive to demonstrate improved power quality at ac mains. Switched reluctance motors (SRM) are used in number of variable speed application. This motor is rugged, reliable, requires low maintenance and its fault tolerant. The main disadvantage of this motor is that it requires power converters for its operation. Many types of power converters for SRM drive are reported in the literature. These converters need stable dc supply for its operation. Various converter topologies are available to energize the phase of the SRM but most effective & commonly used topology is two switched per phase asymmetric converter. There are many converter topologies are published in the literature. The objectives of the topologies are to reduce the number of switches per phase, reduce the cost of converter and firing circuit. The performance of proposed reactor circuit fed SRM drive has been compared with the conventional DBR based SRM drive. This concept can be implemented by further by improving the PF and speed control of SRM Drive performance is simulated in Matlab/Simulink environment