Electric machinery diagnostic/testing system and power hardware-in-the-loop studies

This paper presents an electric machinery diagnostics (EMDS) system that improves on the traditional methods of either using simulation of a power system and its component or scaled down physical models to diagnose faults in hardware under test (HUT). The EMDS couples actual power hardware to a virtual simulation of the power system through a sim-stim interface (SSI) which sources and sinks power to the HUT, performing power hardware-in-the-loop (PHIL). Since the goal of the EMDS is to perform fault diagnosis when the HUT is connected to a physical system, then SSI must be transparent in terms of losses, bandwidth and dynamic range. By its very nature, the SSI adds complexity to the system by the introduction of its internal components (such as sensors, A/D and D/A converters, power amplifiers and operational software). This paper gives the key issues that enables the EMDS to perform PHIL diagnostic studies enabling one to test power equipment as if the device is connected to the actual power system without risking damage to both the equipment and the actual system.