Model and Geometric Characteristic of Multi-quadrants Security Region for Active Distribution Network

The region-based method has been applied in transmission systems and traditional passive distribution systems without power source. This paper proposes the model of multi-quadrants security region (MQSR) for active distribution network (ADN) with distributed generation (DG). The MQSR is modeled considering the constraints of state space, normal operation and N − 1 security guideline. Afterwards, the geometric characteristics of MQSR are observed on the case grids with different DG penetration levels. The MQSR can be located in multiple quadrants of the state space. For different DG penetrations, the shape and security feature of MQSR are also different. Finally, the region map is first discovered, which summarizes the features of different kinds of distribution networks.