Voltage Stability Index For Distribution Network Connected In Loop Configuration

In power distribution networks, voltage instability can lead to voltage collapse and thus power blackout. A considerable amount of research has been carried out on voltage stability analysis of transmission and radial distribution networks. However, voltage stability analysis considering loop nature of distribution network is largely unaddressed. In this paper, a simplistic analytical approach is proposed, based on circuit analysis and famous biquadratic method to evaluate voltage stability of loop distribution networks in terms of voltage stability index (VSI). This work derives mathematical expressions for VSI of loop configuration for two realistic cases. The performance of proposed VSI is initially evaluated for Korean Electric Power Corporation distribution network. Benchmark analysis has been conducted on IEEE 69 bus test distribution networks to demonstrate the validity of the proposed approach in comparison with relevant works. The proposed approach is also applied for distributed generation placement and faults identification analysis. The results demonstrate the performance improvement in VSI of loop-based distribution networks which are expected to be useful for practical applications of future smart grids.