On-line Monitoring of Instantaneous Over-voltage Intelligent Monitoring of EMUs

Abstract

Since high-speed EMUs have high requirements for the reliability of the traction power supply system and the safety of train operation, the online monitoring and analysis of transient over-voltage are of great significance. By analyzing and comparing the characteristics of the existing power grid over-voltage online monitoring devices at home and abroad, and due to the difficulty in detecting the power grid voltage on the high-speed train, a new type of over-voltage online monitoring using the broadband transmission characteristics of the equipment is proposed for the high-speed train. The principle of the scheme is to reconstruct the real-time voltage waveform of the primary side of the transformer by convolving the secondary side voltage waveform of the vehicle-mounted voltage transformer through the fast Fourier transform with the transformer-specific transmission parameter model and to correlate the relevant data, such as power, voltage fluctuation, harmonic distortion, etc. Simultaneously, simulation and experiments are carried out to verify the validity and stability of the scheme algorithm. The experimental results show that the system has good response characteristics, high measurement accuracy, and stable and reliable working conditions. The system achieves the expected design goals, and it has been successfully applied to the online monitoring equipment of EMU power quality. While monitoring the over-voltage of the power grid, this system provides data support for the research on the aging and life of the onboard high-voltage electrical equipment.