Harmonic stability analysis of single‐phase converters in electric multiple units based on an impedance model with harmonic linearization

Low-frequency oscillation, harmonic oscillation and instability issues in railway vehicle-grid systems pose challenges to the system stability safe operation. Previous studies constructed linear time-invariant impedance model of system, which ignored internal frequency coupling loss accuracy. To fill this gap, modelling method based on linearisation is proposed. The derived provides a clear physical insight into relations between ac dc variables improves Then, systematic analysis analysed proposed model. electrical control parameters at frequencies above below fundamental are summarised. mechanisms these then discussed. Finally, accuracy results verified by scan hardware-in-the-loop results.