New Approaches to Designing of Electrical Machines for Modern Controlled AC Electric Drives

Abstract

In this paper, we consider new possibilities realized in alternating current electric machines that are designed for controlled electric drives and powered by semiconductor frequency converters. We concentrate on the possibility of improving the technical and economic performance of the system by taking into account the combined work of the semiconductor converter and the engine under development. The design of asynchronous electric machines for a semiconductor converter is shown to allow significantly improve its energy performance and expand the control range in terms of electromagnetic moment. The possibility of improving the mass–dimension parameters of synchronous machines operating in frequency-controlled systems is substantiated. We show that it is possible for these machines to exclude completely loss from synchronism. We established that synchronous reluctance machines can have specific indices close to those of asynchronous motors, and they realize a significantly larger overload torque in this case. Calculated methods for the synthesis of asynchronous electric drives that were successfully tested in the development of a series of main drives of the D423 drilling rig are proposed. These electric machines were designed for mechanisms with a fanlike load (mud pump) and with an active reluctance torque (winch drive). A synthesis method for the SRMTD synchronous reluctance engines that were tested on an engine for a cold pipe rolling mill is developed.