考虑风电消纳的风-蓄联合系统N-1安全校正方法

当前风-蓄联合系统优化调度模型未整体考虑电网的N-1安全,导致支路过载风险急剧增加。基于此,提出了一种考虑风电消纳的风-蓄联合系统N-1安全校正方法。该方法建立了抽水蓄能电站的连续可微模型,基于两步评估法辨识系统N-1故障下的高风险过载支路并形成高危风险集,推导出考虑基态和N-1故障下的安全约束,以各类发电机和负荷有功调整量最小为目标函数,建立了消除支路有功越限的N-1安全校正模型。目标函数中,以过载支路对风电机组的有功灵敏度作为趋势指标,动态调整各控制量的调整优先级,在充分挖掘系统内各机组的潜能、消除系统安全隐患的情况下,尽可能减少电网弃风。以IEEE57节点标准系统为算例,采用线性规划方法对模型求解,测试结果证明了所提方法的有效性和正确性。

N-1 Security Rescheduling Method for Wind-Storage Combined System Considering Wind Power Consumption

The current optimal dispatching model of wind-pumped storage power system fails to give a full consideration of the N-1 security of power grid, resulting in a sharp increase in the risk of branch overload. For this problem, an N-1 security rescheduling method for wind-pump storage combined system considering wind power consumption is presented in this paper. With this method, a continuously differentiable model of pumped-storage power stations is established, and based on the two-step evaluation method, the high-risk overload branch under the N-1 fault is identified and the high-risk set is formed, and accordingly, the safety constraints in the state of normal and under the N-1 fault are deduced. With the minimization of generators and loads active power adjustment as objective function, the N-1 security rescheduling model to eliminate active power overload is established. In the objective function, the active derivative of the overload branch with respect to the wind power is used as a trend indicator to dynamically adjust the rescheduling priority of each control variables, so that the dispatching potential of each unit can be fully exploited, and the system security risks be eliminated, and the wind curtailment be mitigated. Taking the IEEE 57 node standard system as an example, the linear programming method is used to solve the model. The results demonstrate the validity and correctness of the proposed method.