Study On Calculation Of Power System Economic Dispatch Based On Modified Biogeography-based Optimization

Economic dispatch(ED)is one of the most important issues in power system optimal operation.As an optimization problem,ED problems exhibit high-dimensions,heavy nonlinear,non-differentiable,non-smooth and multi-modal characteristics,and the solving method is expected to have excellent optimization ability.In recently years,with the development of modern intelligent techniques,intelligent optimization methods based on evolutionary computation have been effectively applied into ED problems,and fruitful research results have been achieved.Therefore,studying the intelligent optimization method based on evolutionary computation and its application in the ED problems has important theoretical and practical values.A new biogeography-based optimization(BBO)variant is proposed,which is based on multi-topology and quantitative orthogonal learning.In allusion to the defects of BBO algorithm,on the one hand,multi-topology immigration strategy is brought into BBO to enhance the exploration ability.On the other hand,the quantitative orthogonal learning process is proposed.This process can help the algorithm to investigate the solution space systematically.Numerical results show that the modified strategies can effectively enhance the performance of basic BBO algorithm and the proposed algorithm has better performance than other BBO variants and various intelligent optimization methods.A constraints handling method is proposed,which is used to handle the constraints in the static economic dispatch model.The constraints handling process is embedded into the proposed BBO variant algorithm.Modify the optimization variables in each offspring individual to make all candidate solutions in feasible solutions,when the offspring individuals are generated by the parental individuals.It can guarantee that the solutions meet the constraints strictly.Numerical results show that the proposed constraints handling method is more effective than typical constraints handling method with penalty functions.The proposed method can also obtain the dispatch scheme with less generation cost than various methods in existing literatures.The proposed BBO variant algorithm is applied to solve the dynamic economic dispatch(DED)problems.To deal with the ramp limit constraints,which don't exist in the SED problems,a new inequality constraint with upper and lower bound is obtained by combining the ramp limit constraint and generation capacity constraint.Truncation strategy is adopted to handle the new inequality constraint.Numerical results show that the dispatch scheme obtained by the proposed algorithm has less generation cost than that obtained by other various algorithms in existing literatures.The proposed algorithm also has better performance in robustness.