Research On Reactive Power And Voltage Control Of Regional Power Grid Connected By Multiple New Energy Sources

With the rapid development of social economy,the development and utilization of renewable energy has become the only way for the sustainable development of society.However,a large number of new energy stations changes the flow characteristics of the power flow in the grid,thus changing the voltage distribution grid,distributed power output and has strong randomness,and will lead to network voltage fluctuation,easy to cause the problem of voltage limit.In addition,the existing methods of grid voltage mainly depends on the capacitor and transformer tap adjusting,did not make full use of new energy resources distributed reactive power station,the volatility of the output of distributed power easily lead to the problems of power equipment,without frequent action of repeated adjustment and other conventional stations,affecting the safe operation of power grid and equipment.Based on this,this paper has done the following research work.First,the effect of new energy sources on reactive power and voltage of regional power grid.The characteristics of reactive power source of new energy sources and the effect of new energy power flow on the node voltage are analyzed.In view of different load characteristics,the influence of different new energy sources on PCC point voltage is analyzed.Second,study on the effect of different reactive power and voltage control methods.The different load model considering,studied the influence of PCC voltage and power factor of the change of transformer and reactive power compensation;the wind farm as an example,research on the new energy plant effects of reactive power voltage control of PCC voltage and power factor.Thirdly,study on the optimization of reactive power and voltage of single time section.The react ive power and voltage control strategy of the new energy plant station is studied,and the optimal control model of reactive power and voltage of the single time section is constructed,and an example analysis is carried out.Forthly,the optimal control m ethod of reactive power and voltage based on time sequence is studied,and the optimal control of the coordination of the time and the time to the multi time scale is studied.In the optimization process,multi objective optimization based on the trend of integrated load change,the number of daily regulation of the discrete reactive power control devices are calculated,and the simulation results show that the proposed method is effective.