Keywords: power HIL, hardware-in-the-loop, PHIL, real time digital simulation, ripple filters, three-phase converters, phase synchronisation, control methodology, virtual machines, virtual microgrids, static synchronous compensator, STATCOM, load dynamics
Synchronisation and application of three-phase converters utilising the power-hardware-in-the-loop concept
This paper addresses the timely issues of synchronisation and application of three-phase power converters, connected in parallel, utilising the power-hardware-in-the-loop (PHIL) concept. Without proper synchronisation, the converters are normally not able to distinguish the currents that circulate between them. This paper focuses on a control methodology for achieving precise phase synchronisation for equal load sharing, with minimum current circulation between the parallel connected power converter modules, and robust dynamic system control under various transient conditions. The possible converter applications for the configuration presented in this paper are the virtual machine (VM) concept and a conceptual virtual microgrid (VMG), which utilises the reactive power compensation ability of the static synchronous compensator (STATCOM). These concepts provide a solution for de-risking these costs as it utilises the PHIL concept in conjunction with high-fidelity models and detailed load dynamics. Selected experimental results on two, 25 kVA and 15.3 kVA, converters connected in parallel are presented.