25 kV-50 Hz railway power supply system emulation for Power-Hardware-in-the-Loop testings
25 kV-50 Hz railway power supply system emulation
for Power-Hardware-in-the-Loop testings
This paper presents a methodology to consider the impedance of a grid in power hardware in the loop (PHIL) experiments to validate power converter control in presence of harmonics or resonances in the network impedance. As the phenomena to emulate are in a large frequency range, the skin effect in conductors has to be taken into account. A procedure is developed to model the network. Then, the model is simpliﬁed to reduce the computation requirements and discretised for real-time implementation. The proposed method has been applied to analyse the harmonic interactions due to on-board converters running on a 25 kV-50 Hz railway infrastructure for frequencies from 0 to 5 kHz. The model is computed in Matlab-Simulink, a SpeedGoat Performance Machine and a linear power supply are used for a real time implementation. The converter under test and the test bench are presented. Some experimental results are presented, showing the feasibility and the usefulness of the proposed approach.