Research On Low Voltage Control Of Power System

With the continuous development of China’s construction,residential electricity load increase rapidly,great changes have taken place in bureau of civil electrical properties,exacerbated the contradiction between supply and demand,leading to the phenomenon of low voltage electricity deterioration,deterioration of power quality.Because the residents use TV and radio are three kinds of load,so the power quality control measures are not in place.It is an urgent problem for the distribution network to effectively control the low voltage of the residents’ power consumption.In view of this background,according to the current distribution network status,a probabilistic power flow voltage reactive power centralized decentralized control strategy is proposed.Based on the actual situation of distribution network load,power load fluctuation found for residents affected by seasonal,weather and other factors affected only by a certain period of the load as the reactive power compensation capacity calculation of distribution network data has certain limitations.Namely,the deterministic power flow can not fully reflect the load flow situation of the distribution network.Therefore,this paper uses the Monte Carlo simulation based probabilistic power flow calculation method,this method can better reflect the load of each node in the network.According to the data obtained from probabilistic power flow calculation,the optimal capacity and corresponding nodes of reactive power compensation in distribution network can be obtained by genetic algorithm.This paper is called the lower level control of reactive power compensation.The lower level control takes the active network loss in the distribution network as the objective function,and obtains the compensation capacity of the reactive power compensation node in the distribution network.The lower control of reactive power compensation capacity as the feedback value,with the qualified rate of the voltage,maximum voltage and rated voltage of the expected value of the minimum value,minimum network loss as the objective function of the transformer is adjusted to achieve centralized control of the distribution network,the paper called the upper control of voltage and reactive power compensation.This control strategy can improve the voltage acceptance rate of power distribution network and improve power quality.