Analytical of Loop closing Operation Based on Multi-dimensional Index System

Steady-state current and impulse current are important indicators for judging the feasibility of loop closing operations. Nevertheless, only these two indicators are unable to offer the information for changes in power grid before and after the operation as well as guiding suggestions to operators. By using a multi-dimensional index system, a more comprehensive judgment for the feasibility of loop closing is provided from three dimensions: static assessment, transient assessment and hybrid assessment. These not only cover such important evaluation indicators as steady-state current and impulse current, but also include the changes of power flow, the limits of N-1 and the trend of current or voltage. The simulation of loop closing in EPRI-36 bus system verifies the correctness and effectiveness of multi-dimensional index system, which provides a reliable basis for the security and stability of power grid.