Network-assisted corrective actions against short-term and long-term voltage instability in power system with DGs

This paper proposes a new strategy for computer network-assisted corrective actions against short-term and long-term voltage instabilities in the electricity power distribution system connected with renewable-energy distributed generations. The proposed strategy aims to save the distribution system from imminent voltage collapse due to contingencies occurring in the subtransmission network, distribution network, or distributed generation circuit, by executing appropriate operations that include coordinated generator controls, capacitor switching, load tap changing, load shedding, etc. This paper uses state-of-the-art digital signal processing technology for determining correct stability controls and modern computer networking technology for monitoring distribution system operating states and transmitting data and stability control commands. This paper presents the design of corrective actions against short-term and long-term voltage instability in a DG-connected power distribution system, and hardware implementation for real-time execution of corrective actions using a new two-layer architecture for network monitoring, data transmitting, and control delivering. Typical adaptive stability enhancement is illustrated.