Development Of Three-phase Load Unbalanced Management Device

Due to the increasing depletion of fossil energy,the problem of energy saving and loss reduction of power grid has attracted more and more attention.The unbalanced three-phase load is the main reason of power grid loss,which is of great significance to its research.The traditional reactive power compensation device has high cost in the treatment of the unbalanced three-phase load,which has harmonic pollution and has not fundamentally solved the problem of the unbalanced three-phase load.The method of manual commutation has the problem of low efficiency and long commutation time.To solve these problems,online three-phase unbalanced load control method was put forward,in this thesis,in view of the unbalanced three-phase load control device of optimized configuration of the control strategy and the specific research.In order to reduce the load switching time and improve the stability of switching time,the switching control strategy of switching over zero shut-off and fixed delay conduction is proposed based on the analysis of the traditional strategy.In order to solve the error problem of traditional RMS value calculation,this thesis uses RMS value calculation based on frequency detection.Aiming at the control algorithm of three-phase load equilibrium distribution,two evaluation indexes of three-phase current unbalance and number of action switches are established in this thesis.An improved binary particle swarm optimization algorithm is proposed to optimize the load balance distribution problem by adding the "competition" mechanism to the particle position update.Finally,a practical example is given to demonstrate that the proposed algorithm can effectively solve the problem of load balancing distribution and reduce the number of action switches.In order to improve the online three-phase unbalanced governance device treatment effect and economic benefit,optimize the configuration,this thesis establishes the years such as value investment cost and operation maintenance cost,transformer and line loss,and other evaluation index.On this basis,an improved genetic algorithm is proposed to optimize the configuration number and installation location of the device.The data analysis shows that the proposed method can optimize the switch position and quantity to meet the economic benefit and governance effect.Base of theoretical analysis,online three-phase unbalanced load control device principle prototype,test under different load properties of the commutation time,the experimental results show that the device can quickly switch and is not affected by load properties,at the same time set the three-phase unbalanced load experiment platform,verify the effectiveness of the proposed load balanced allocation algorithm.