光伏出力具有较强的波动性且难以预测,同时配电网中量测装置不足导致负荷估计精度差,因此传统的确定性电压控制方法不完全适用于主动配电网。电压越限是导致配电网中光伏发电弃光或停运的主要原因,文中提出了一种考虑光伏出力和负荷不确定性的鲁棒区间电压控制方法。该方法计算出最优无功补偿决策的同时,给出光伏电站的允许有功出力区间。所提出的方法在保证系统安全的基础上使得光伏电站尽可能运行在最大功率点跟踪模式。在改进的IEEE 33节点算例系统上进行了分析,通过蒙特卡洛仿真验证了所提方法的鲁棒性。
The output of photovoltaic(PV)power is frequently fluctuated and difficult to be predicted.Besides,the estimation errors of load demands are significant due to the limited real-time measurement devices in distribution networks.Therefore,the conventional deterministic voltage control strategies cannot be well applied into active distribution networks.The over-limit voltage is the main reason for the PV curtailment or outage in distribution networks.This paper proposes a robust intervalvoltage control strategy considering the uncertainties of PV output and load demand.The optimal var compensation strategies and the allowable active power interval for the PV station are calculated in the strategy.The method proposed guarantees system safety and is able to make the PV station running at the maximum power point tracking mode at most possible.Finally,by taking the modified IEEE 33-bus system as an example,the robustness of the proposed method is verified through Monte Carlo simulation.