Traction main circuit over-power-off area charging control method and traction main circuit

Abstract

The invention discloses a traction main circuit over-power-off area charging control method, and the method comprises the steps: S01, disconnecting the connection between a traction main circuit and atraction power supply network when the input current Id of the traction main circuit reaches a preset threshold value Id1, and executing the step S02; S02, collecting the current Ic of an intermediate capacitor, when the current Ic is smaller than a preset threshold value Ic1, recovering the connection, and when the current Id is larger than or equal to It+Ic', breaking the connection, and executing the step S03; and S03, when the current Id is less than It+Ic1, recovering the connection and keeping the connection. The invention further discloses a traction main circuit which comprises a control unit, a direct-current voltage input end, the intermediate capacitor and an inversion module; the direct-current voltage input end is provided with a first voltage detection part, the intermediatecapacitor is connected with a second voltage detection part in parallel, and the control unit controls the action of the switch unit according to the input current of the inverter and the detection values of the first voltage detection part, the second voltage detection part and the first current detection part. The control method and the main circuit have the advantages of safety, reliability and the like.

Description

technical field [0001] The invention mainly relates to the technical field of rail transit, in particular to a charging control method for a traction main circuit passing through a power outage area and the traction main circuit. Background technique [0002] At present, a large part of the vehicles in the urban rail field use the third rail to receive current. Due to different power supply zones and branch roads, the third rail cannot be connected together. There must be a power outage, which is the power outage area. When the train After passing through the power-off port, because the intermediate capacitor of the train inverter still has voltage, the train can continue to run for a certain distance by the intermediate capacitor voltage, and the capacitor voltage will decrease accordingly. The voltage difference of the capacitor is relatively large, so the instantaneous current will be very large, which will cause faults such as current overcurrent, intermediate voltage ov...

AI Technical Summary

Problems solved by technology

When the voltage of the intermediate capacitor drops to the undervoltage threshold, if the network voltage suddenly recovers, there will be a large charging current to charge the capacitor due to the large voltage difference between the network voltage and the intermediate capacitor voltage, and the final waveform is Figure 3 waveform (the upper part is network voltage, the lower part is charging Current), it will cause faults such as DC overcurrent, intermediate voltage overvoltage, inverter output overcurrent, etc. At the same time, due to excessive charging current, it will also have a great negative impact on the life of the capacitor

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