Experimental investigation of normally-on type bidirectional switch for indirect Matrix Converters

In this paper, the novel normally-on type bidirectional switch, in which is comprised of SiC-JFET, SiC-SBD, and Si-IGBT is proposed for one of a protection method of the Matrix Converter (MC). When the MC becomes gate block situation, a diode clamp circuit or auxiliary circuits keeps inductive load current loop in a conventional MC utilized a bidirectional switch. We focus that the normally-on type SiC-JFET becomes turn-on state, when zero gate bias voltage and a SiC-devices have a good tolerance capability for short current than silicon devices. These characteristic of normally-on type SiC-JFET is used to replace diode clamp circuit in MC driver system. The experimentation based on indirect MC induction motor driver system was carried out. The experimental result of IM driver shows that the proposed bidirectional switch can overcome a generated inductive load current by IM. Finally, in order to design heat sink, the power loss of each devices of proposed switch was estimated by experimental results.