Adaptive distance relay setting for parallel transmission network connecting wind farms and UPFC

The paper presents an adaptive distance relay setting for parallel transmission network connecting wind farms. The ideal trip characteristics of distance relay is greatly affected in presence of mutual coupling of parallel transmission lines as the apparent impedance is significantly affected. Similarly, the reach setting of the relay for the lines connecting wind farms is significantly affected as the relay end voltage fluctuates continuously. Thus, the proposed study focuses on developing adaptive relay setting for parallel transmission network including wide variations in operating conditions of wind farms and effect of mutual coupling, together. Further, the performance of the proposed adaptive relay setting for parallel lines including Unified Power Flow Controller (UPFC) indicates the potential ability of the proposed analytical approach in handling distance relaying in transmission system.