A time-varying generalized short-circuit ratio calculation method based on thevenin equivalent parameter identification using transient data
The generalized short-circuit ratio helps effectively reflect the strength of the receiving end power grid.The calculation of the generalized short-circuit ratio is based on Thevenin's equivalent admittance matrix of the receiving end power grid at DC feeder node,in which the influence of dynamics of all components on the strength of receiving end power grid is ignored.In this paper,a time-varying generalized short-circuit ratio calculation method is proposed based on Thevenin's equivalent parameter identified through transient data.The voltage of infeed buses and the power injected into infeed buses are used to identify the time-varying admittance matrix of receiving end AC system based on multi-port Thevenin equivalent model and least-squares method.Then time-varying generalized short-circuit ratio is calculated based on Thevenin's equivalent admittance matrix,which can accurately reflect the influence of the system dynamics on the strength of the receiving end AC system.Finally,the accuracy of proposed method is verified by case studies on single infeed system,and the practical effect of this proposed method is verified by case study of provincial system,and the effect of dynamic load characteristics of on time-varying generalized short-circuit ratio is analyzed.
generalized short-circuit ratiomulti-infeed HVDC systemmulti-port Thevenin equivalenttime-varying parameter identificationtransient data
万方数据
维普
