Practical Steady-State Security Region-Based Risk Limiting Dispatch Considering Active and Reactive Power Coordination Strategy

With the rising penetration proportion of renewable energy in intelligent power system, the voltage security become increasingly evident. This paper presents a risk limiting dispatch model based on AC power flow, where the node voltage and the line current constraints can be considered. The proposed method is based on the practical steady-state security region, which describes the overall area satisfying the above constraints within the node active and reactive power injection space and whose boundary can be effectively approximated by one or a few hyperplanes from an engineering perspective. Meanwhile, a coordination strategy of reactive power compensation and active power RLD is also developed, considering the voltage fluctuation caused by the variability of renewable energy. On the basis of reserving a certain margin of reactive power equipment for online realtime voltage regulation, the reactive power support in the system is fully utilized, facilitating an economical optimal dispatch of active power. Energy storage technology is also considered in dispatch. Case studies on test system are used to assess the proposed method. Results verify the necessity for RLD based on AC power flow and show that the proposed method can improve the computing efficiency of the risk optimization problem.