Research On The Countermeasures To Solve The Low Voltage Problem In Distribution Network Using Reactive Power Compecation

In recent years, because of the rapid growth of rural electricity load, low voltage problems occured frequently, due to the growing problem of the insufficient power supply. In order to solve the low voltage problems, several schemes have been adopted, including increasing diameter of low-voltage lines, re-planning supply area of distribution transformers, and replacing larger distribution transformers etc. But the existing schemes are difficult to meet the urgent demands of users, due to the long period used to solve the problems. So it is necessary to study on fast solution for low voltage disposal.It proves that the main reason causing the decline in voltage quality is the deficiency or the unreasonable distribution of the system reactive power. So it is necessary to use parallel lowvoltage capacitor as an important technological option. For applying the technology better, it is essential to deploy configuration strategy and to develop programs in engineering application, on which few people studied currently.In this paper, the research work carried out in two aspects.Firstly, we investigated the reactive power control strategy for voltage compensation in low voltage distribution network. Through analyzing the relationship of voltage and reactive power, we designed the nine area control model and studied on the reactive power control strategy for voltage compensation in low voltage distribution network. According to the strategy, we designed the intelligent capacitor for voltage compensation and the intelligent reactive power compensation device.Secondly, we investigated engineering solutions for low voltage problem in low-voltage power network using the intelligent reactive power compensation device. We analyzed the basic theories and formulas commonly used to assess voltage and reactive power on the overhead line, designed the voltage and reactive power model at the end of the low-voltage overhead line, and simulated V-Q curves of common low-voltage overhead lines using Matlab. According to the simulation results, we designed the reactive power compensation typical configuration table for engineering application, and indicated the scope and qualifications of the table.Finally, we investigated the engineering implementation steps of using the reactive power compensation device to control the low voltage problem, and built two low voltage disposal pilot projects. According to the feedback information of the pilot projects, it is confirmed that the control strategy, configuration strategy, and engineering implementation scheme discussed above are reasonable and effective, with a wide range of adaptability and high application value.