Alternating current leakage detection system and method supporting power supply mode conversion, and vehicle

Abstract

The invention provides an alternating current leakage detection system and method supporting power supply mode conversion and a vehicle, the system comprises an alternating current insulation detection device, a leakage current contactor, a leakage detection resistor, a circuit breaker and a controller, and the circuit breaker, the leakage current contactor and the alternating current leakage point detection device are sequentially connected in series and are connected between a neutral line and the vehicle; the leakage detection resistor is connected in parallel with the leakage current contactor; the alternating current insulation detection device is used for detecting a vehicle leakage current value and sending an early warning / alarm signal to the controller, and the controller is used for controlling the leakage current contactor to be switched on or switched off according to a vehicle state, so that a vehicle auxiliary power supply mode is a TT mode or an IT power supply mode; an isolation transformer does not need to be added, and the vehicle design cost is reduced; when an electric leakage fault occurs, an IT power supply mode is automatically converted, a fault load power supply does not need to be cut off, the influence on the operation order is reduced, and the vehicle availability is improved.

Description

technical field [0001] The invention belongs to the technical field of AC leakage detection, and in particular relates to an AC leakage detection system, method and vehicle supporting power supply mode conversion. Background technique [0002] The statements in this section merely provide background information related to the present invention and do not necessarily constitute prior art. [0003] The auxiliary power supply system of rail transit vehicles often adopts two power supply modes: TT or IT. The TT power supply mode can achieve AC220V power supply without adding an isolation transformer, and the TT power supply mode requires an isolation transformer to achieve AC220V power supply. And in the TT power supply mode, due to the small loop impedance of the load when the load leaks, the continuous increase of the current will cause the equipment to burn or even the vehicle to catch fire. Due to the large loop impedance and small leakage current during leakage, the operat...

AI Technical Summary

Problems solved by technology

And in the TT power supply mode, when the load leaks due to the small loop impedance, the continuous increase of the current will cause the equipment to burn out or even the vehicle to catch fire. The power supply of the faulty unit must be cut off immediately. Due to the large loop impedance and small leakage current during leakage, the operation can be maintained without cutting off the power supply, and the availability is high, but it is necessary to ensure that the leakage detection device continues to alarm

The previous leakage detection system needs to be configured according to the power supply mode, or an isolation transformer is added to realize the power supply, and the equipment cost is relatively high.

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