Double-side tripping protection system for DC traction power supply system based on digital communication

Abstract

The invention discloses a bilateral combination jump protection system of a direct-current traction power supply system based on digital communications. Two direct-current traction protection monitoring devices, two heavy combination jump transfer relays and two RS485 turn fiber converters are arranged for each traction substation. A communication loop among the direct-current traction protection monitoring devices is built through the RS485 turn fiber converters. Whether the traction substations in the overhead line system run in a normal state or an over-zone state, the bilateral combination jump protection system can guarantee that fault messages of any two feeder lines in the interval of the overhead line system can be exchanged reliably, and the reliability of bilateral combination jump protection on the direct-current traction power supply system is improved. In addition, the bilateral combination jump protection system of the direct-current traction power supply system based on digital communications has the advantages of good real-time performance and low cost.

Description

technical field [0001] The invention relates to a double-side joint jump protection system of a DC traction power supply system based on digital communication. Background technique [0002] When the urban rail transit DC traction power supply system is in normal operation, two DC power supplies in two adjacent substations are generally used to supply power to the same section. In this power supply mode, if a fault occurs in this section, the system needs to disconnect the DC feeder circuit breakers corresponding to two adjacent substations through double-sided joint trip protection, so as to completely isolate the fault in this section. [0003] The main points of realizing double-sided joint jump protection: [0004] First, realize the distinction of tripping signals: DC traction power supply system faults are generally divided into two types: transient faults and permanent faults, so the system also needs to determine whether to start the belt fault of the DC traction pro...

AI Technical Summary

Problems solved by technology

[0007] First, based on the signal transmission method of the control cable, this method directly transmits the status of the relay between the two stations through the cable. Using this method, it is not possible to monitor the circuit in real time for disconnection or poor contact.

When there is disconnection or poor contact in the jump circuit, there may be problems of malfunction or refusal

[0008] Second, based on the shielded twisted pair signal transmission method, this method first uses the device to collect the status of the relay, and then transmits the signal to the adjacent station through the twisted pair. Using this method mainly has the disadvantages of poor anti-interference ability and limited communication distance question

[0009] Third, the optical fiber-based signal transmission method first uses the photoelectric conversion device to collect the state of the relay, and then transmits the signal to the adjacent station through the optical fiber. The circuit design of this method is more complicated

[0010] The above three methods all have the following disadvantages: first, relays are used to distinguish the jump signal, and the circuit design is complicated; second, a large number of relays are used, and the overall action time of the double jump has a certain delay

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