Optimum estimation of series capacitors for enhancing distribution system performance via an improved hybrid optimization algorithm

Abstract

As the load on distribution networks grows, system operators and planners are constantly challenged with the issue of voltage regulation or enhancing the quality of supply to customers at the load end of lengthy distribution lines. This paper presents the optimum determination of series capacitor units in a distribution system to maximize energy-saving and enhance voltage levels. Interestingly, series capacitors can enhance the capability of transmission lines, reduce line losses, enhance the performance of buses with large induction motor loads and reduce voltage flicker. At the same time, the limitations of series compensation are taken into consideration while calculating its optimum values. To achieve the planning objective and optimal load flow objective, two strategies: The Improved Grey Wolf Optimization method (I-GWO) and Tabu Search (TS), are hybridized to get the benefit of their advantages. The I-GWO has a movement strategy called dimension learning-based hunting for enhancing the balance between global and local search and maintaining diversity. The proposed (I-GWO-TS) algorithm can solve mixed-integer programming to achieve the planning and the optimal load flow objectives. The proposed method can be applied to a real Egyptian distribution system that is heavily loaded, with poor voltage regulation, and also has high-power losses. The obtained results demonstrate the capability of the proposed approach to determine optimal series capacitors' location and sizing for maximization of energy saving. Further, the proposed method improves the network performance regarding the voltage profile and power losses, although the limitations of including series compensation were considered in the distribution system.

Metaheuristic‐based graded objective function strategy for optimal thyristor‐controlled series capacitors estimation in weak distribution systems with uncertain distributed generation

“…This motivates the authors to devise an algorithm to address this limitation. ✓ Drawbacks of fixed series capacitors: While fixed series capacitors have shown improvement in the performance of electrical distribution networks, they lack flexibility and often bring abrupt changes, akin to steps on a ladder [11][12][13][14][15][16].…”

“…One of the effective strategies for enhancing the performance of distribution networks is sequential compensation [11][12][13][14][15]. This approach is particularly well suited for weak networks as it directly influences their sensitivity by modifying the overall impedance of the lines, thus positively impacting voltage stability as the load increases [16]. Consequently, this article aims to optimize the performance of distribution networks by implementing this strategy.…”

“…✓Challenges with existing optimization methods [17–40]: Despite significant progress in mathematical optimization methods, simultaneous achievement of the objective function and constraints remains problematic, leading to convergence issues in some cases. This motivates the authors to devise an algorithm to address this limitation. ✓Drawbacks of fixed series capacitors: While fixed series capacitors have shown improvement in the performance of electrical distribution networks, they lack flexibility and often bring abrupt changes, akin to steps on a ladder [11–16]. Additionally, these capacitors can only effect change in one direction, potentially leading to issues like high voltage.…”