Influence Of High Density Energy Storage Device On Power System Transient Stability

In recent years,with the continuous expansion of the scale of modern power system,the situation of multiple HVDC transmission lines connected to the AC power grid is gradually formed.Because the probability of HVDC transmission failure is much greater than that of AC transmission line,and the traditional transient stability control measures gradually show shortcomings,so the technology of using energy storage to support power system transient stability has attracted great attention.Based on the transient stability of Zhejiang power grid when HVDC blocking occurs,this paper studies the control strategy of high-density distributed energy storage device used to improve the transient stability of power system,combined with the application of related cases.In this paper,the power controller of double loop control outer loop is studied.A specific energy storage control loop is built by using power system transient simulation software PSASP.A droop control strategy of virtual inertial control for primary frequency modulation of Zhejiang power grid is designed,and the effect of system frequency modulation is compared with that of general ping-pong control.Aiming at the problem of low cycle load shedding caused by the decrease of system frequency when DC blocking occurs in Zhejiang power grid,this paper studies and designs the installed capacity,starting time and supporting time of distributed energy storage,so as to obtain the best control mode of energy storage and the best frequency supporting effect.The process and results are simulated by psd-bpa software.In this study,the reactive power support function of energy storage device is designed,and the supporting effect of active and reactive power support of energy storage device on power system voltage fluctuation,power angle oscillation,large-scale power flow transfer and other issues is comprehensively studied.Through the psd-bpa software for specific simulation analysis,the feasibility of energy storage reactive power compensation scheme is obtained.The research shows that the high power density distributed energy storage device has a very good effect on improving the transient stability of power system by using the appropriate control mode.