Research on Reactive Power Coordination Control Scheme of Energy Feedback Device in Urban Rail Transit Power Supply System

Abstract

Objective Currently, the urban rail transit power supply system mainly relies on the main substation SVG (static var compensator) for reactive power compensation. During non-operating hours at night, the medium voltage loop network lines of urban rail transit power supply system are basically unloaded, and the charging reactive power of the lines is high, causing SVG to operate under heavy load for a long time. To alleviate the compensation pressure of SVG, a reactive power coordination control scheme for energy feedback device is proposed, coordinating SVG and the energy feedback devices in the traction substation to jointly participate in reactive power compensation. Method The calculation method of the energy feedback device reactive power compensation capacity is analyzed, and the reactive power coordination control strategy for the SVG and energy feedback device is proposed. Finally, on-site tests on a certain metro line are performed, verifying the correctness of the above strategy. Result & Conclusion When the energy feedback devices of a metro line are all put into use for reactive power compensation, the SVG reactive power compensation capacity can be reduced by 2.6 Mvar to the most, and the total active power loss of the me-dium voltage loop network line can be reduced from 0.7 MW to about 0.5 MW.

Keywords

• urban rail transit
• power supply
• energy feedback device
• reactive power compensation