Pareto Optimal Allocation of Flexible Fault Current Limiter Based on Multi-Objective Improved Bat Algorithm

Abstract

With the sustainable growth in the integration of distributed generation units in the distribution network, the probability of the fault current level exceeding the rating of existing components increases. Cascaded H bridge fault current limiter is widely used in the power grid due to its advantage in inhibiting surge current flexibly. In order to equilibrate the objective functions of its cost, fault current mitigation effect, and the weighted load reliability index, a novel methodology is proposed to simultaneously optimize the location and size of the limiters in the distribution network. Therein, the sensitivity factor considering the Monte Carlo fault simulation model is introduced to reduce the search space and rank candidate locations referencing the actual conditions. And then, according to the candidate locations and considering different conflicting objective functions, a multi-objective improved bat algorithm is employed to obtain the Pareto optimal solution set. Also, life cycle cost and net present value are introduced to construct an economic model to access the scheme costs and service life. The proposed approach is verified using the modified IEEE 33-bus distribution systems with DGs and IEEE 30-bus Benchmark system. The results demonstrate that the proposed method exhibits higher efficiency in finding optimum solutions and provides a new economic configuration idea for the practical engineering application.

Keywords

• Pareto optimal configuration
• cascaded H bridge fault current limiters
• sensitivity factor analysis
• multi-objective optimization
• life cycle cost