Arcless Current Interruption of DC 150A using a Hybrid DC Circuit Breaker Consisting of SiC-MOSFET and Metal Contacts

DC circuit breakers (DCCBs) have received considerable attention due to the increasing demand for DC power transmission and distributed generation.Hybrid DCCBs that consist of mechanical switches, semiconductor devices, and metal-oxide varistor elements offer fast interruption and a low contact resistance when the mechanical contact is closed.Although semiconductor devices in conventional hybrid DCCBs are turned on by arc voltage between the metal contacts, the contact voltage with a high melting-point material can turn on power devices without generating an arc discharge.The magnitude of the molten-bridge voltage of tungsten is sufficient to turn on metal-oxide-semiconductor field-effect transistor devices under specific conditions.In this report, an arcless commutation of DC current is described by using two-pole tungsten contacts connected in series.Finally, we performed DC current (300 V-150 A) interruption and succeeded in obtaining arcless current interruption with a probability of 100%.No erosion was observed after several interruptions of DC 150A.