Study on Real-Time Load Simulator for Testing Propulsion Inverter Test

A newly-built inverter has to undergo a series of stress tests in the final stage of production line. This can be achieved by connecting it to a dynamometer consisting of a three-phase machine joined by a rigid shaft to a DC load machine. The latter is controlled to create some specific load characteristic needed for the test. In this paper a test method is proposed, in which no mechanical equipment is needed. The suggested test stand consists only of a inverter to be tested and a simulator converter. Both devices are connected back-to-back on the AC-side via smoothing reactors. The simulator operates in real-time as an equivalent load circuit, so that the device under test will only notice the behavior of a three-phase machine under consideration of the load. In order to prove tightness of the suggested test method, the simulation and actual experiment carried out emulation for a 2.2 kW induction motor