基于二次变异改进生物地理学优化算法的限流器配置方法

针对开关型限流器的优化配置问题,为准确评估限流器动作后的限制效果,建立了断路器的最大开断电流与限流器配置的数学关联模型,在此基础上以各支路两侧安装限流器的电抗值为优化变量,以区域电网配置限流器的单位成本限流效果最大化为优化目标,以母线短路电流、断路器最大开断电流以及单个限流器的限流电抗为约束条件,建立限流器优化配置模型。以余弦迁移模型和柯西变异的生物地理学优化(BBO)算法为基础,并针对优化变量中相邻维度对适应度函数影响相近的特点,在算法中引入相邻维度间的二次变异操作,提出了基于适用于限流器优化配置的二次变异改进BBO算法。以某500 kV区域电网为例,进行限流器优化配置;为了验证所提改进BBO算法的优化性能,运用多个不同优化算法对限流器优化配置模型进行求解,优化结果表明,改进BBO算法具有较好的收敛速度、稳定性以及寻优能力。

Configuration Method for Fault Current Limiter Based on Improved Biogeography-based Optimization Algorithm with Second Mutation

According to the optimal reconfiguration issues of switch type fault current limiter (FCL), a mathematical relevance model of maximum braking current of circuit breaker (CB) and reconfiguration of FCL is established to precisely evaluate the limiting effect after fault current limiter operates. On this basis, taking reactance values of FCL installed on two sides of each branch as optimal variables, and the best current limiting effect of per unit cost of FCL as an objective function,an configuration optimal model of FCL is constructed, in which the constraints of short-circuit current of buses, the maximum breaking current of CB and the maximum reactance of each FCL are considered. After that, the biogeography-based optimization (BBO) algorithm based on sinusoidal migration model and Cauchy mutation is adopted. Considering that the adjacent dimensions in optimization variables have similar influence on objective function, the second mutation operation between adjacent dimensions is introduced into the optimal algorithm and an improved BBO algorithm based on second mutation is proposed. Finally, in order to verify the performance of the proposed improved BBO algorithm, different optimization algorithms are applied to solve the optimal configuration model of FCL which takes a 500 kV regional power grid as an example. The results show that the improved BBO algorithm has better convergence rate, stability and searching ability.