Research On Reactive Power Compensation Configuration Of 500 KV Substation With Large-scale Wind Farm Interconnected

With the implementation of the Renewable Energy Law of China and the promulgation of a series promotion policy of renewable energy development,the wind power installed capacity of China is growing rapidly,and there is a large-scale wind farm development trend.However,wind power has the characteristics of volatility and scheduling difficulties,large-scale wind power will be adversely impact on power system,so the consideration of the impact of wind power on the reactive power compensation in the substation in the feasibility study stage of power transmission and transformation project has practical significance.This paper focus on reactive power compensation of 500kV substation with the Large-scale wind power integration,the following works have been done.Firstly,a reactive power balance analysis method round the substation is proposed.With the substation as the research entity,this method calculates the flow through the inlet and outlet of each substation;use the constant relationship between the reactive power demand and the active trans,nission and then determine the configuration of the low-voltage reactor groLp and low-voltage capacitor bank.In th1s Inethod,lle substation for the study,calculated How through the inlet and outlet of-each substation main transformer and power flow,the use of reactive poxver demand relationship between the active transmission,substation needed to determine the configuration of the low-voltage reactor group and low-voltage capacitor bank.Finally,we verify the conclusions using analysis of critical flow.Taking the project of 500kV substation as an example in a certain province,we calculate the needed capacity of low voltage reactive power compensation device,and demonstrale its effectiveness.Secondly,this paper undertakes the N-1 in the case oflarge-scale wind power integration with the consideration of the impact of wind generation on power system.With the reactor group and capacitor bank configured a certain capacity,study how the change of power output from the wind access substation,under different power load lnode,will impact the main lines of normal operation and N-1,thcii analyze the system flow and voltage level.Take A,13 substation of 500kV from some province for example,in the framework of the vision in the grid,under the maximum load and minimum load respectively,undertake the N-1 for the main lines.At the same time,with the increase of the wind power output gradually from 0?90%,to validate weather the the reactive power compensation device can meet the system's stability,under the reactor group and capacitor bank configured at a certain capacity.Finally,From the view of system transient stability,we analyze the effect of diflerent power grid fault on substation wattless compensation configuration.We caleulate reactive power demand and accomplish N-1 check,then analyze stability and fluctuations of system reactive power.Due to the limited capacity of low voltage reactive power compensation device,it is different to realize continuous adjustment.We show this can be improved by using dynamic wattless compensation device.We demonstrate its effectiveness by the project of 500kV B substation in a certain province.This paper studys the method for calculation of reactive power compensation device for 500 kV substation on the bases of large-scale wind power integration.The proposed method is used to guide engineering practice and practical examples are used to verify its correctness and effectiveness.Our work is valuable to reactive power compensation and optimization.