Research On Ship Power System Harmonics Based On Improved Adaptive Genetic Algorithm

Recently, when lots of nonlinear loads are added into ship power system with the development of power electronic, the problem of harmonic is from bad to worse, not only take down the quality of power, but also threaten safe run of ship power system.Thus, we should analyse harmonic and take necessary measures.Considering non-linear load such as motor, node voltage method is used to calculate fundamental power flow;considering the decoupling of fundamental power flow and harmonic power flow, linear analysis is used to calculate harmonic power flow.A kind of Improved Adaptive Genetic Algorithm is brought up. The locations and parameters of active and passive harmonic filters are determined simultaneously to meet the harmonic voltage distortion limits and security constraints with a minimum total investment cost. In the search process,ranking selection, direct comparison for individuals that break restrictive conditions, and genetic manipulation that adaptively changes the entire cross-species probability and mutation probability according to the fitness value of the degree of concentration are used for optimal allocation of filter equipment.Combination of a ship power system example, program for application is made. Compared with the situation of all passive filters or all active filters,the results illustrate the effectiveness of optimizing the allocation of unity; With a simple comparison of genetic algorithm, simulation results show that the improved adaptive genetic algorithm improves the convergence speed and enhance the optimization capability.