A GaN based bidirectional switch for matrix converter applications

The operation of bidirectional switches, based on normally OFF GaN devices and suitable for matrix converter applications, is investigated in terms of static power dissipation. To this end, nine homemade prototypes, suited for the nine legs of a three-phase/three-phase converter, have been specifically designed and fabricated. A typical four steps switching sequence, for exchanging the current from one leg to another, has been implemented. Results show that "diode mode" operation, exhibited by the GaN device in the OFF state, strongly affects power dissipation.