Design and Control Methods of Bidirectional DC-DC Converter for the Optimal DC-Link Voltage of PMSM Drive

Abstract

This paper shows the design and control methods of the bidirectional DC-DC converter togenerate the proper DC-link voltage of a PMSM drive. Conventionally, because the controllable powerof the PWM based voltage source inverter is limited by its DC-link voltage, the DC-DC converter isused for boosted DC-link voltage if the inverter source cannot generate enough operating voltage forthe PMSM drive. In this paper, to obtain more utilization of this DC-DC converter, optimal DC-linkvoltage control for PMSM drive will be explained. First, the process and current path of the DC-DCconverter will be illustrated, and a control method of this converter for variable DC-link voltage willthen be explained. Finally, an improvement analysis of the optimal DC-link voltage control method,especially on the deadtime effect, will be explained. The DC-DC converter of the proposed controlmethod is verified by the experiments by comparing with the conventional constant voltage controlmethod.