Abstract: The grid-connection of distributed generations and the gradually expanding scale of distribution networks make the traditional fault location methods more difficult. A multi-strategy improved Hybrid Whale Optimization Algorithm Gray Wolf Optimization (H-WOA-GWO) combined with region correction fault location method is proposed to address this problem. Firstly, the WOA encircling contraction and spiral updating mechanisms are integrated into GWO to construct a hybrid algorithm to effectively improve the convergence speed; then the nonlinear convergence factor, improved leader wolf position and adaptive hunting weights are applied to enhance the search adaptability, global development capability and shorten the iteration time. Different location models are established to choose in constructing the objective function based on the evaluation function value method, and the region correction strategy is proposed by analyzing the potential information of the pseudo-optimal solution. After simulation verification, under triple faults: the correct rate of hybrid algorithm is 11 percentage points centa higher than that of single algorithm, and the iteration time can be saved by 0.326 7 s; the correct rate and solution time after combining with the region correction strategy are improved by 17 percentage points and 74.88%, respectively, compared with that of pure hybrid algorithm. It shows that the proposed algorithm and correction strategy can quickly and accurately recognize multiple and multi-deformed node faults with efficient solution speed and stability.

Key words: improved binary gray wolf optimizer, whale optimization algorithm, region correction, distributed generations, fault location