Optimal Dispatch Of Island Microgrid Based On Improved Cuckoo Algorithm

With the support of national policies,island microgrid technology has developed rapidly.Considering the randomness of wind power and intermittent solar energy,ensuring the sustainability of energy supply is one of the problems to be solved in island microgrid system.In addition,in order to meet the experience and economic benefits of island residents,the island microgrid combination mode may be composed of photovoltaic,wind energy,ocean current energy,diesel generating units and controllable fresh water load.As the island microgrid involves the joint operation of multiple types of generators,the stability and economy need to be taken into account in the operation process.Therefore,it is of practical significance to study the optimal scheduling problem of island microgrid.In order to solve the problem that cuckoo algorithm converges slowly in the late iteration and is easy to fall into the local optimal value,an improved cuckoo algorithm based on the dynamic change of cuckoo egg detection probability and step size control is proposed,which enhances the global search performance in the early stage and the local search ability in the late stage.The IEEE-30 bus test system and the optimal scheduling problem of six thermal power units are used to verify the optimization ability of the improved cuckoo algorithm,and the good optimization performance of the improved cuckoo algorithm is verified.According to the structure and operation conditions of island microgrid,the optimal scheduling model of island microgrid system considering environmental penalty cost and desalination benefits is established,and the objective function and corresponding constraints of island microgrid system economic operation are determined.The improved cuckoo algorithm is used to solve the optimal scheduling model of island microgrid system,and the results are compared with those of other commonly used optimization algorithms.The results show that the improved cuckoo algorithm only needs 75 iterations,and the global optimal solution is 3068.03 yuan,with the least number of iterations,the highest accuracy and the best optimization effect.According to the optimization results of cuckoo algorithm,the optimal operation scheme of island microgrid system is determined.Priority is given to the use of battery to regulate the power of the system,and the use of seawater desalination system to consume excess electric energy,so as to reduce the energy consumption and working time of diesel engine.The scheduling scheme not only ensures the load demand of the system,but also reduces the impact on the environment,and improves the utilization rate of clean energy.