The Analysis On Operation Scheme Of Beijing Power Network After Electromagnetic Loop Untying

With the fast development of Beijing power network, the 500kV loop network has been finished, which is conjoined with the existing 220kV loop network, forming an electromagnetic loop with the two voltage levels. In such circumstance, the short circuit current in some substations will exceed the rated value of the 220kV circuit breakers. To limit the short circuit current, the 220kV loop structure has to be broken down and the power supply area is scheduled to be divided into four separated regions.This paper presents the calculation and analysis results of Beijing power network in various operating states, including power flow distribution, short circuit calculation, N-l analysis, static voltage stability, etc. before and after the break down of the 220kV loop, in order to find out the benefit and weakness of the system after it is divided into four supply regions.