机组出力调整对静态电压稳定影响的预测算法研究

Prediction Algorithm for the Influence of Power Generation Adjustment on Static Voltage Stability

为解决传统离线分析计算量大、在线分析对实时性要求高的缺陷,提出了无需实时数据的、可用于在线分析的电力系统电压稳定预测算法。根据正常工况下,支路有功功率与两端相位差近似成正比的规律,利用任意时刻的初始潮流数据,结合潮流转移因子表,即可快速估算发电机出力调整后的关键支路电压、潮流及临界运行状态。制定了反映有功裕度和无功电压灵敏度的综合稳定指标,利用估算值预测支路电压稳定水平的发展趋势,再由该指标与发电机无功出力限制确定有功功率的最大可行调节范围。最后通过加权指标评价不同出力调节量对系统电压稳定的影响。对我国某实际电网的仿真结果验证了本文算法的有效性。

In order to overcome the defects of conventional off-line and on-line static stability analysis, i.e. huge computation and strict real-time demanding respectively, a novel method based on index prediction is proposed, which can be used on-line without complex calculation or real-time data. According to the fact that active power is di- rectly proportional to phase separation of line voltages in normal operating conditions, by using initial power flow data at any time and combining flow transfer factor table, the line voltages, quick prediction can be made about key branch voltage, flow and critical operation state after a generator changes its output. An integrated stability index is formula- ted to characterize active margin and reactive voltage sensitivity. The estimated value is drawn on to forecast develop- ment trend of the branch voltage stability level, and then the index and generator reactive power output limits are used to determine the maximum adjustable range of active power. Finally, the weighted indicator is adopted to evaluate the voltage stability lever under different output of the generator. Simulation results of a certain power system in China verify the validity of the proposed algorithm.