Power System Transient Simulation Based On Precise Integral-Differential Quadrature Method

Power system transient simulation is the most widely used method in power system transient stability analysis.In actual engineering and application,it has become the main means of power grid planning,design,operation,prediction and analysis.In the power system transient simulation,the method of solving the differential equation is very important,so it is of great significance to study the numerical integration method in the power system transient simulation.Precise integration-differential quadrature method is an improved new calculation method that uses differential quadrature method to deal with inhomogeneous terms in differential equations.In this paper,the precise integration-differential quadrature method is used to carry out electromechanical transient simulation,electromagnetic transient simulation of power system,and electromechanical transient simulation considering the electromagnetic transient process of the stator.The main research contents are as follows:The mainstream precision integration methods are compared and analyzed,and the integration format that expands the precision integration-differential quadrature method to fourth-order precision is given.The precision analysis of the processing format of the non-homogeneous terms in this method is carried out,and the Taylor series The expanded coefficient comparison shows the truncation error of the inhomogeneous term integral format.Through a simulation example,the feasibility of the precise integrationdifferential quadrature method for power system transient simulation is preliminarily verified.The electromechanical transient simulation mathematical model of the synchronous generator set based on the thyristor excitation control function and the valve control function respectively deduces the integration format suitable for the precise integrationdifferential quadrature algorithm,and the precise integration-differential quadrature method is given.The program flow diagram of transient simulation and the matters needing attention in practical application.The precise integration-differential quadrature method and the precise time history method are used to simulate the electromechanical transient state of the example system.The simulation results show that the precise integration-differential quadrature method is an effective method for the electromechanical transient simulation of power systems,and can be simulated with large steps,which has the advantages of good numerical accuracy and high simulation efficiency.Based on the full-order Park equation and rotor swing equation of the synchronous generator,the electromagnetic/electromechanical transient state equation expression suitable for the precise integration-differential quadrature method is derived.The precise integration-differential quadrature method and the fourth-order Runge-Kutta method are used to carry out electromagnetic transient simulation and electromechanicalelectromagnetic transient hybrid simulation of the example system respectively.The comparative analysis of the simulation results shows that the precise integrationdifferential quadrature method It has certain potential advantages in improving the calculation efficiency of electromagnetic transient simulation of power system,which further verifies the effectiveness of the precision integral differential quadrature method for power system transient simulation.