Research On Voltage Stability Control And Location And Capacity Determination Of Static Var Compensator

With the development of China’s power grid,new features of high voltage,large capacity,and long-distance transmission have gradually emerged.The scale of the power system continues to increase,and its structure and operation mode have become more and more complicated.In this context,flexible AC transmission(FACTS)technology has been widely researched and applied because of its flexible control methods,and the benefits of improving the stability and reliability of power systems and improving power quality.As a typical representative of FACTS devices,static var compensator(SVC)can quickly adjust the reactive power of the system and maintain the voltage stability of the node,which can greatly improve the voltage stability of the power system,so it is widely used in the power system.This article mainly studies the voltage stabilization control and site selection of static var compensator.First,the topology,operating principle and working characteristics of SVC are analyzed.Based on the typical TCR-TSC SVC,the control strategy of SVC is analyzed in combination with its control structure,and the SVC is carried out in Matlab through an equivalent infinity system.Fault simulation,analysis and verification of SVC control strategy and work process.The conventional structure of the SVC voltage controller is introduced.A nonlinear PI controller is designed by introducing a nonlinear function for the nonlinear characteristics of the SVC device.And through the second-order system simulation to compare its effect with conventional control.Aiming at the shortcomings of conventional genetic algorithms widely used in reactive power optimization,optimization is made by improving the crossover operator and mutation operator,and the optimization effect is compared with the conventional genetic algorithm through three detection functions.The improved genetic algorithm is used to optimize the control parameters of the SVC voltage controller,and the optimization effect is verified by a typical fault simulation of a two-machine system model.Finally,the site selection and volume determination scheme of SVC is designed.First,summarize and explain the commonly used location methods.Then,three optimization indicators are introduced to construct a site-to-capacity optimization model that comprehensively considers active power loss,voltage offset and installation cost.The flower pollination algorithm is used to optimize the model.And carry on simulation experiment in IEEE14 node system,carry on power flow calculation under the condition of 150% overload and 180% overload,get the corresponding simulation result and analyze and explain.