敏感负荷对含新能源配网规划的影响

Impact Analysis of Voltage Sensitive Load on Planning of Distribution Network with New Energy

由于新能源出力不稳,未来高比例新能源接入会使配电网电能质量下降,从而降低敏感负荷的运行效率,严重时导致设备运行异常甚至故障。在此背景下,电压下降至敏感负荷电压耐受曲线的不确定区域内时,可能会发生负荷损失的情况,需在配电网规划加以重视,以提高电网的安全性和经济性。文中以变频调速电机为例进行建模,分析其电压敏感性,并估算了变频调速器在电压耐受曲线不确定区域内的故障概率。然后将电压敏感型负荷的损失量纳入配电网风险规划模型中,对现有风险规划进行改进,算例结果验证了所提方法的可行性和有效性,为未来配电网规划提供了参考。

Due to the volatility of renewable energy output,the power grid with high proportion of renewable energy integration frequently faces the power quality declining. This reduces the operation efficiency of sensitive load and further leads to abnormal operation or even malfunction of equipment. In this background,the load loss may occur when the voltage falls to the uncertain region of the sensitive load voltage tolerance curve,which should not be neglected. Such load mode possibility should be considered for the distribution network planning in order to improve the security and economy of the power grid. In this paper,the frequency variable motor is taken as a typical load to model and analyze in terms of its voltage sensitivity. First,the fault probability of the frequency converter in the uncertain region of the voltage tolerance curve is estimated,and then the loss of voltage sensitive load is calculated and incorporated into the distribution network risk planning model to improve the adaptability of the existing method. The results of the test example verify the feasibility and effectiveness of the proposed method,which will be a reference for the future distribution network planning.