A novel bidirectional three-phase AC-DC/DC-AC converter for PMSM virtual machine system with common DC bus

Abstract

In the industrial production stage of a drive, its control algorithm must be tested for its validity with real machine. Testing with real machine could pose some serious challenges. During the testing, if the control algorithm starts behaving unexpectedly, it may cause serious damage to the real machine or drive. Such hazardous operating conditions can be avoided by replacing a real machine with a power electronic converter based ‘Virtual Machine’ (VM) test-bench. The VM can be designed to allow the device under test (DUT) to be tested at actual power with the help of a power electronic converter test setup and the motor model. The VM controls the current drawn from the DUT to match with that of estimated by the motor model. The existing VM system comprises of AC-DC followed by DC-AC converter, increasing the number of converter stages in the system. In addition, both the converters require independent control which increases the control complexity. This multistage conversion stage can be eliminated by replacing AC-DC-AC emulator with AC-DC converter supplied by common DC bus to DUT and VM both. Taking into account, this paper proposes a novel single-stage, three-phase bi-directional AC-DC converter topology suitable for VM system.