一种无功平衡与临界潮流快速分析方法及其在特高压可控高抗需求分析中的应用

Fast Analysis Method of Reactive Power Balancing and Critical Power Flow and Application to Study Controllable Shunt Reactors Requirement in UHV Grid

随着我国特高压电网规划和建设的不断深入,可控高抗作为重要的无功电压调节手段备受关注,亟需对其在特高压电网中的需求和布点作出科学判断。首先提出可操作性强的特高压电网无功平衡原则,深入分析电网元件的无功需求和有功传输之间的定量关系;进而提出一种可仅基于有功电力流,以变电站为中心的电力系统无功平衡及其临界潮流快速分析方法;随之将这种方法应用到特高压电网可控高抗的需求和布点研究中。该方法不仅可以对指定的规划方式进行快速定量分析,还可以给出变电站临界潮流和变压器负载率之间的关系曲线及其变化趋势,从而增强了研究结论对不同负载水平和运行方式的适应性。对"东纵"特高压输变电工程进行可控高抗的需求和布点研究,给出工程适用性强的结论和建议,为特高压可控高抗示范工程方案的确定和后续工作的开展提供了技术依据。

With the planning and constructing of the ultra high voltage （UHV） grid of China, the controllable shunt reactor （CSR） attracts more attentions as an important control measure for var and voltage. Therefore it is urgent to analysis and study the deployment of UHV CSRs scientifically. In the paper, firstly, the feasible var balance principles were proposed; secondly, the quantitive relationship between the var demand and active power going through the reactance element was analyzed in depth. Furthermore, only based on active power flow, the fast analysis method of substation-centered var balance and critical power flow was proposed and applied into the study of the deployment of the UHV CSR and its requirement and location. The method can not only be applied into the fast quantitive analysis of the given power flow pattern, but also can be used to obtain the relation curve between the critical power flow and the transformer load rate, thereby, the adaptability of the study conclusions to the various load levels and power flow patterns is increased. Finally, the requirement and the deployment of CSRs in UHV ＇Dongzong＇ transmission project were studied with the proposed method, and the conclusions and recommended deployment schemes were given, which provides the technical basis for the pilotproject ofUHV CSR.