Fault Location Method for Power Supply Rails in Low and Medium-speed Magnetic Levitation Traffic Based on Double-ended Traveling Wave Frequency Variation Characteristics
Low and medium-speed magnetic levitation power supply rails are prone to DC ground faults during power supply. Due to its short supply distance and complex earthing network structure, it is not easy to locate the fault point ac-curately after a DC earth fault has occurred. To addresses the above issues, based on the characteristics of the train running without contact between the car body and the track, this paper establishes a low and medium-speed magnetic lev-itation traction power supply system, analyzes the advantages and disadvantages of double-ended fault ranging and single-ended fault ranging, and studies the relationship between the time domain distribution and frequency domain dis-tribution of fault traveling waves after an earth fault occurs in the power supply track. Meanwhile, this paper analyzes the generation mechanism of the traveling wave spectrum through formula calculation.It is concluded that the frequency dis-tribution of the fault traveling wave is not affected by the impedance and transition resistance in the station, but only related to the location of the fault point and the time of the fault traveling wave reaching the two ends of the line. Thereby, a fault location method is proposed for low and medium-speed magnetic levitation traffic power supply rails based on the double-ended frequency variation characteristics, and the location of the fault point is calculated based on the fault travel-ling wave frequency characteristics and travelling wave speed. The simulation verification reveals that the method is not affected by the location of the fault point, the size of the transition resistance, and is applicable to single ground fault and multiple ground fault type. The fault error is always maintained within 1％. Compared to traditional track fault ranging methods, the measurement accuracy is higher and is suitable for low and medium-speed magnetic levitation traffic supply track ground faults.
low and medium speed magnetic levitationgrounding faultsfault locationtraveling wavesfrequency distribution
万方数据
维普
