A Real Time Simulator of a Phase Shifted Converter for High Frequency Applications

This paper presents a switched function FPGAbased Real Time Simulator (RTS) of a synchronous Phase Shifted (PS) converter. The design methods developed contribute to improving the accuracy, the portability, to lowering the cost and the resource demand of RTS models, enabling them to be easily deployed both in hardware in the loop (HIL) simulations, but also in error detection or health monitoring systems where these properties are essential. The research work carried out demonstrates the importance of reducing the simulation time step for avoiding false limit cycling behavior and obtaining an accurate closed loop response of the RTS. The very small time step (20 ns), not achievable with commercial real time simulation tools, helped in accurately modeling the time and frequency response of the converter for switching frequencies of 200 kHz (tested) and above. Although applied to a particular type of DC-DC converter, the methods presented can be used to successfully model a wide range of Switched Mode Power Supply (SMPS) topologies. An innovative hardware platform that enables running the real time simulation model in parallel with the reference converter and facilitates a comparative analysis that proves the fidelity of the RTS of the PS converter was also developed.