Advanced Development of Soft Switching Inverter for AC Motor Electrical Drive Systems

This paper presents a simple circuit topology of the auxiliary active resonant DC link snubber (ARDCL) which is used for the instantaneous space voltage vector modulation ARDCL assisted thrdd phase voltage source soft-switching inverter suitable for small scale PM motor drive applications. The specific related pulse processing drive circuit interface of the auxiliary resonant DC link snubber circuit and its soft-switching operation are discussed from an experimental point of view. In addition to these, the conductive magnetic noise of quasi-resonant snubber-assisted three phase zero voltage soft-switching inverter in the case of PM motor drive in its open loop scheme is actually measured and evaluated by using experimental setup as compared with the general purpose three phase hard switching inverter.

Voltage source inverter

Space voltage vector modulation

Active auxiliary resonant DC link

Soft switching commutation

DC brushless servo motor

Conductive noise reduction