1.云南电网有限责任公司 电力科学研究院;2.西南交通大学 电气工程学院;3.云南电力调度中心
1.Electric Power Research Institute, Yunnan Power Grid Co., Ltd;2.Southwest of JiaoTong University;3.Yunnan Power Dispatch Center
Under the large-scale grid connection of new energy, the problem of the reduction of the regional voltage qualification rate is becoming more and more obvious. The main reason is the instability of the new energy itself and the control strategy that needs to be improved. In order to improve the accuracy and stability of the regional voltage, this paper calculates the DFIG reactive power limit in detail, and considers the overcurrent factor to further correct the DFIG reactive power lower limit. The DFIG control structure is improved, and the GSC reactive power capacity is included for the DFIG reactive power compensation, so that the wind farm retains the maximum active power while deeply exploring the reactive potential, thereby improving the reactive power compensation capability of the wind farm. In addition, a coordinated control strategy is designed in combination with SVG, which can not only retain the flexible compensation capability of SVG, but also enable the wind farm to provide reactive power support and share the burden of SVG compensation. Finally, by analyzing parameters such as sensitivity and reactive power remaining, this paper designs a regional reactive power allocation strategy, further improves the voltage fine control strategy, and verifies the entire set of control theory through the two-region grid-connected system.