Transient Stability Simulation Analysis of Multi Node Power Network with Variable Speed Pumped Storage Units

The output characteristics of variable speed pumped storage are different from conventional hydropower and constant speed pumped storage units. The continuous increase of installed capacity of variable speed pumped storage, poses a severe challenge to the safe and stable operation of the local power grid. Proposed in this paper is a kind suitable for multi-node containing variable speed pump machine storage unit electric power network transient stability method, considering the variable speed pumped storage units by the end of the instantaneous failure prone to sudden drop transient power, the power network with more nodes each busbar voltage stable operation as the goal, according to the regional power grid data under typical operation modes, Based on the power system analysis software package, an electromechanical simulation model of the 7-node power grid with variable speed pumped storage unit was established. The influence on the transient stability of a 7-node power grid is analyzed by removing variable speed pumped-storage units and three-phase short-circuit faults. The transient stability of the power grid can be maintained under the conditions of removing variable speed pumped-storage units and three-phase short-circuit faults, but some bus voltages are higher than the specified voltage upper limit. The reactive power compensation device is installed to improve the voltage stability of the power grid system, which can prevent the overvoltage accident caused by the fault of the communication system, achieve the purpose of multi-node power network stability, and improve the safety and stability of the regional power system when the fault occurs.