Research On Excitation Control And Capacity Configuration Of Synchronous Condenser

With the increasing proportion of new energy integration,the problems of dynamic reactive power shortage and low voltage level of power grid are becoming more and more prominent.The new Synchronous Condenser(SC)has the characteristics of large capacity and fast response speed,and has become the main device to improve the voltage strength of the power grid.However,the research on its excitation system control and capacity configuration strategy is still not perfect.Further research on the control strategy and configuration of the Synchronous Condenser is of great significance for improving the voltage support capability of the Synchronous Condenser.In this thesis,in order to improve the voltage intensity of the system,aiming at the problems of low regulation of grid-connected bus voltage and high cost of capacity configuration scheme by the conventional control strategy of excitation system of Synchronous Condenser,a feedforward control of excitation system based on GWO-PID algorithm and a capacity configuration strategy considering node coupling and reactive power intensity are proposed to realize the real-time regulation of grid-connected bus voltage by Synchronous Condenser and improve the rationality of capacity configuration scheme of Synchronous Condenser.The main contents are as follows :(1)The mathematical model of Synchronous Condenser is established.Based on this model,the excitation control and reactive power output principle of Synchronous Condenser are analyzed.The voltage regulation performance of each reactive power compensation device is compared and analyzed,which lays a theoretical foundation for the subsequent research on excitation system control and capacity configuration of Synchronous Condenser.(2)Aiming at the problem that the conventional control of the excitation system of the Synchronous Condenser cannot adjust the grid-connected bus voltage in time,a feedforward control strategy of the excitation system considering the grid-connected bus voltage is proposed with the grid-connected bus deviation of the Synchronous Condenser as the feedforward input.Grey Wolf Algorithm(GWO)is introduced to tune the parameters of PID controller in feedforward link,and the feedforward control strategy of Synchronous Condenser excitation system based on GWO-PID algorithm is obtained.The influence of each excitation control strategy on the dynamic voltage deviation,steady-state voltage loss and dynamic adjustment time of the grid-connected bus is analyzed by an example,and the effectiveness of the control strategy is verified.(3)Aiming at the problem of weak voltage support effect and high configuration cost caused by unreasonable capacity configuration scheme of Synchronous Condenser,the equivalent impedance is used to measure the electrical coupling relationship between nodes,and the electrical distance is included in the conventional location index of Synchronous Condenser.The Multiple Renewable Energy Station Short Circuit Ratio is used to quantitatively analyze the grid voltage intensity,and the configuration cost of Synchronous Condenser is measured by equal annual value method.The capacity configuration strategy of Synchronous Condenser considering node coupling and reactive power intensity is proposed.The configuration cost of Synchronous Condenser is analyzed by an example when each node meets the requirements of grid voltage intensity,and the correctness of the configuration strategy is verified.(4)Aiming at the problem of low voltage intensity caused by frequent changes of reactive power demand in power grid with high proportion of wind power,based on the capacity configuration strategy of Synchronous Condenser considering node coupling and reactive power intensity,the capacity configuration strategy of Synchronous Condenser in power grid with different proportion of wind power is proposed.Combined with a high proportion of wind power in Northwest China,the effectiveness of Synchronous Condenser excitation system control and capacity configuration strategy is verified.