Research On Reactive Power Compensation Scheme Of Urban Rail Power Supply System

The design of urban rail reactive power compensation is an important part in the design of urban rail power supply system,but the method and theory of urban rail reactive power compensation design are not at present.The modeling and simulation of urban orbit power supply system with reactive power compensation device is the basis of the research on the capacity design and location of urban track reactive power compensation device.In this paper,the urban rail power supply system with SVG reactive power compensation device is studied,and technical support is provided for the design of urban track reactive power compensation from the system modeling and simulation level.This paper first introduces the modeling method of DC network and AC network of urban rail traction power supply system.According to the existing urban orbit reactive power compensation model,the urban rail power supply system with SVG reactive power compensation device is completed and the power flow calculation equation of SVG reactive power compensation device in urban rail power supply system and the corresponding constraint equation.Based on the simple power flow algorithm of power system,a calculation method of AC-DC power flow and the capacity design scheme of reactive power compensation device for urban rail power supply system with SVG reactive power compensation device are proposed.The power flow simulation program of urban rail power supply system with SVG reactive power compensation device is written by using VC ++(Visual C ++).and the power supply calculation of AC-DC is carried out with SVG urban rail transit traction power supply system.Mainly include the common connection point(PCC)reactive power and the main transformer apparent power in the SVG reactive power compensation device before and after the change in time and SVG reactive power device corresponding output situation.Finally,taking the Chengdu Metro Line 1 as an example,the simulation is carried out on the operation of the train at the beginning of the initial day.The reactive power of the PCC in the transformers I and Ⅱ of the Zhao Jiao Shu main transformer substation and the apparent power of the main transformer are analyzed.The simulation results show that the reactive power of PCC in stage I and Ⅱ of the main transformer substation of Zhao Jiao Shu is capacitive.After the SVG reactive power compensation device is input,the PCC capacitive reactive power is reduced and the apparent power of the main transformer increases The Combined with the measured data,the rationality of the calculation algorithm of urban rail power supply with SVG reactive power compensation device is verified.This paper evaluates the existing scheme of reactive power compensation capacity of Zhao Jiao Shu main transformer substation of Chengdu Metro Line 1,and points out that the capacity design margin of paragraph I reactive power compensation device is too large and the capacity of second stage reactive power compensation device is moderate...