Study On Passive Filter Capacity Optimization Of Hybrid Compensation System Based On Particle Swarm Optimization

With the development of the national economy,more and more non-linear load appears in people's daily life.Since the large amount of non-linear load invested into the power grid,the power quality of power grid is seriously affected.In order to guarantee the normal operation of the grid,the harmonic problem and power factor reduction problem needs to be improved.A hybrid compensation system composed of a series of compensating devices such as a static var generator,a passive power filter and an active filter is developed.Passive filter has been focused for its simple structure,lower running cost and higher stability.But filter effect of the passive filter will also be affected by many factors,such as the system harmonic impedance fluctuations,components manufacturing errors.In order to obtain better filtering effect,the compensation system consisting of passive filter and active filter is used at the same time.Active filter is usually used as optimization of a passive filter filter,and there is a coupling between the capacity of active power filter and the parameters of the passive filter.Because of the fact that the traditional power theory is not applicable to the calculation of non-sinusoidal system power component,this thesis has listed the hybrid compensation system with passive filter as the research object.Therefore,In this thesis,the new capacity calculation method based on IEEE Std 1459-2010 power theory is deduced,the influence of different capacity distribution methods is compared,the parameters of passive filter are calculated,and the parameter optimization method of passive is designed filter by changing the value of weight of Particle Swarm Optimization(PSO).Firstly,the calculation results of IEEE Std 1459-2010 power theory used in single-phase and three-phase circuit and the equivalence principle of line loss are introduced in detail.On the basis of this,the compensation capacity of the corresponding passive filter and active power filter is deduced for the three-phase three-wire hybrid compensation system.The rationality of the new method in the calculation of three-phase sinusoidal circuit and three-phase non-sinusoidal circuit capacity is compared and analyzed.Secondly,the structure and working principle of the single-tuned filter and the high-pass filter are introduced in this thesis.The influence of the performance of passive filter under different capacity allocation methods is studied.The effects on passive filter parameter from fixed capacity allocation and system impedance's influence on filter efficiency is further analyzed.Finally,the basic principle and algorithm process of standard particle swarm optimization algorithm is introduced,and the setting of algorithm parameter is analyzed.Aiming at the deficiency of standard particle swarm optimization(pso)algorithm,the inertia weight value of the linear gradient concave function is added into the standard particle swarm optimization algorithm.Its advantages have shown obviously through comparing.Through the optimization model of a typical parallel hybrid compensation system,the optimization target and the constraint mode are proposed for the passive filter,and the solution method is given to optimize the parameters of the passive filter.By comparing the result of the traditional method of particle swarm algorithm,the effect is much more obvious.