Short Circuit Ratio Analysis Based on Real-time Thevenin Equivalent Parameter Estimation
A method for determining the transient stability of wind power connected to multi station power systems based on short-circuit comparison was proposed.Firstly,an equivalent model was established for the new energy grid connected system,and the Thevenin equivalent parameter method was used for time-domain simulation to solve the transient Thevenin equivalent parameters of the system;on this basis,the short-circuit capacity of the AC system was calculated,the short-circuit ratio of the new energy grid connected system was derived,and an algebraic relationship between the short-circuit ratio and node voltage was constructed so as to obtain the calculation formula of the system short-circuit ratio regarding node voltage;finally,the critical short circuit ratio was gained based on the maximum transmission power of the system,and the real-time evaluation of system transient stability was achieved through comparison.The simulation results show that the Thevenin short-circuit ratio calculation based on time-domain simulation is accurate and the algorithm has strong adaptability.When the short-circuit ratio is less than the critical short-circuit ratio,the system is in the characteristic unstable region,while it is in the stable region on the contrary.
Thevenin equivalentrenewable energy grid connectiontransient stabilityshort circuit ratiocritical short circuit ratio
万方数据
维普
