风电爬坡事件多级区间预警方法

Multi-level Early Warning Method for Wind Power Ramp Events

大规模风电爬坡事件对电力系统功率平衡问题影响显著,严重时可能导致停电事故。基于区间分析理论,提出了一种风电爬坡事件多级预警方法,对可能造成的危害程度进行预先警告。考虑风电爬坡预测研究现状,采用区间数形式对其不确定性进行描述;针对风电爬坡事件强波动性对电力系统功率控制的影响,以维持静态频率偏差在允许范围内为前提,分析采用不同功率控制措施满足功率平衡所对应的风电爬坡幅度允许区间;确定各等级预警区间的预警界限,并利用区间排序方法计算各预警区间的概率,实现多级预警。算例仿真分析及比较结果表明,所述方法能够给出各级预警区间的界限值及概率分布,物理意义明确,且简便快速,利于实时滚动运行,体现了有效性和实用性。

Large-scale wind power ramp events （WPRE） have a significant impact on the power balance of power system and may lead to load shedding in severe cases. Interval analysis method is introduced to establish a multi-level early warning method for WPRE, hy which the warning information can be provided to reflect the degree of potential harm inflicted by WPRE. According to the characteristics of WPRE, the number of intervals is introduced to describe the uncertainty of wind power. In view of the impact of large volatility of WPRE on power control and with the static frequency deviation maintained within the allowable range as precondition, the permissible intervals of ramping amplitude are analyzed to determine the boundaries between different warning levels corresponding to different power control measures. Comparison of the boundaries with the prediction results of wind power, multi-level early warning for WPRE shows that the interval ranking method can provide the probability distributions of different warning levels. Simulation results and comparative analysis demonstrate that, both the boundaries and probability distributions of different warning levels, with clear physical meaning, can be provided by the simple and rapid method beneficial to real-time scrolling operation and testifying to the effectiveness and practicability of the proposed method.