Comprehensive Control Method And Application Of Voltage And Reactive Power In Distribution Network

With economic development and people's living standards improve, distribution system load is also growing, so the power supply reliability and power quality also put forward higher requirements. Voltage quality is an important indicator to measure the quality of power supply is in line with the standard, and the voltage regulation and reactive power optimization is an important measure to ensure the quality of voltage. The purpose of voltage and reactive power optimization of distribution network is to reduce the network loss, improve the voltage level and improve the quality of the voltage. In this paper based on the power distribution network, especially urban distribution network and the rural distribution network load distribution and structure characteristics, reactive power compensation configuration mode and adjust the pressure means two aspects of, using voltage and reactive power centralized and decentralized coordinated control of the basic ideas, study on distribution network voltage reactive comprehensive management method and engineering application problems.Specific research:(1) On the basis of systematic review of the development of power flow calculation technology, the realization principle and characteristics of deterministic power flow and probabilistic power flow calculation method are compared and analyzed. In order to describe the uncertainty and randomness of load power variation of distribution network, the probabilistic power flow calculation model of distribution network based on Monte Carlo simulation is established. Through the IEEE30 system simulation test and the actual distribution system probabilistic load flow calculation, analysis of the uncertainty of power load of distribution network operation characteristics and operation behavior, especially the influence on voltage distribution and for the subsequent distribution network voltage reactive power optimization control method provides a more reliable and more consistent with the distribution network load change data.(2) Based on the review of the distribution network voltage reactive power optimization control method research and application of foundation, a comparative analysis of the voltage and reactive power decentralized control, centralized control and coordination control the realization principle and characteristics. Based on the probabilistic power flow and global operation information, the strategy and implementation method of voltage and reactive power centralized decentralized coordination optimization control of distribution network with reactive power compensation equipment and transformer tap changer are presented. A distributed voltage and reactive power centralized decentralized coordinated control model based on probabilistic power flow is constructed by using genetic algorithm. Distribution network voltage reactive power centralized decentralized coordination optimization control model is divided into upper control and lower control. The lower control is to achieve the decentralized control of distribution network with the objective function of the minimum active power network loss as the objective function. Upper control is to voltage qualification rate and the desired voltage value with the rated voltage of the minimum value, network loss minimum as the target function of transformer tap adjustment to achieve centralized control of the distribution network, so as to realize the transformer and the coordinated control of reactive power compensation equipment. Through of Zhuzhou power company an actual distribution network application simulation test. The results showed that with the trend of the deterministic calculation compared, based on probabilistic load flow of voltage and reactive power centralized decentralized coordinated optimization control model can better arrangement of the compensation equipment switching and transformer tap adjustment, effectively avoid the compensation devices and transformer tap frequent switching and adjustment, so as to improve the quality of electric energy, improve the voltage qualification rate.(3) The reactive power optimization control software of the distribution network is designed and developed. The software is based on the control object of the reactive power compensation device and the transformer tap, and adopts the voltage and reactive power centralized decentralized coordinated control strategy based on the probability flow. Through the online collection of distribution network operation data and through the necessary data processing, the reactive power compensation equipment and transformer tap control and adjustment programs are given to realize the reactive power optimization compensation and voltage regulation of distribution network. The practical engineering application shows that the software function design is reasonable, the interface is friendly, the operation is simple, and it provides a good assistant.