A DC voltage detection and control method for a subway regenerative energy feedback device

Abstract

The invention relates to a DC voltage detection and control method for a subway regenerative energy feedback device, comprising two steps: detecting and protecting the DC side voltage, dynamically adjusting the DC starting voltage threshold, and determining a DC voltage reference value. Aiming at the disturbance problem existing in the DC traction network, a voltage detection and protection method is proposed. The disturbance time superimposed on the DC power grid system in the subway power supply system is generally at the microsecond level. When the disturbance occurs, the interference superimposed on the DC power grid can be effectively filtered by the present invention to prevent false protection of the equipment; when the DC power grid When a real overvoltage or undervoltage fault occurs, the protection time does not exceed 1ms, which fully meets the system's response time requirements. Aiming at the problem of circulating current or slow response caused by AC voltage fluctuation, a control method of DC voltage starting threshold and control self-adaptation is proposed. The method is simple to implement, thereby effectively avoiding problems of circulating current or slow response speed caused by fluctuations in AC network voltage.

Description

technical field [0001] The invention relates to the field of power electronics technology and automatic detection and control technology, in particular to a DC voltage detection and control method for a subway regenerative energy feedback device. Background technique [0002] The ground-mounted subway regenerative braking energy inverter feedback device (hereinafter referred to as the energy feedback device) is installed in the traction step-down hybrid substation of the subway station. When the subway vehicle enters the station, it can realize the conversion of the mechanical energy of the subway brake into AC Electric energy is fed back to the power grid for use by station loads or other traction vehicles, achieving the purpose of recycling regenerative braking energy again. When the device works in the rectification mode, it can cooperate with the traction rectifier unit to provide energy to the DC side at the same time, which can reduce the output of the traction rectifi...

AI Technical Summary

Problems solved by technology

This method detects and protects the DC side voltage of the energy feed device, effectively eliminates misjudgments caused by burrs, interference, etc., and ensures the rapidity and accuracy of detection; this method also provides a threshold for the DC starting voltage of the energy feed device Dynamically adjust and determine the DC voltage reference value at the same time, which can solve the problem of circulating current or slow response that may be caused by the AC side voltage being too high or too low, ensuring the reliability of equipment operation

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