含电动汽车充电站的配电网谐波潮流计算

Harmonic Power Flow Calculation of Distribution Network With Electric Vehicle Charge Station

考虑到实际系统中充电站并网点的运行电压一般不是额定电压水平,且在相同功率下,电压值的变化会引起电流值变化。为使充电站并网谐波潮流计算更精确,本文提出一种适用于充电站的谐波潮流计算模型,该模型为考虑了充电站并网侧电压和自身阻抗影响的充电站等效电流源模型,并根据电动汽车充电站的工作原理,提出了一种含电动汽车充电站模型的谐波潮流计算方法。算例采用IEEE-33节点配电网系统,对两种类型谐波源在多种注入方式下进行谐波潮流计算,对比结果表明,计算中修正谐波电流后,含充电站负荷的节点及相邻节点的电压畸变率增大,充电站并网不仅影响本节点还影响相邻节点的电能质量。

The operation voltage of the node where EV （E- lectric Vehicle） charge station connecting to the network is not at rated voltage level under normal circumstances. The variation of voltage will cause the current value changes un- der the same power situation. In order to make the calcula- tion more precise, a harmonic power flow calculation model applied to EV charge station is proposed in this paper, which is an equivalent current model by considering the volt- age influence and self- impedance of connected- grid side of EV charge station. According to the working principle of EV charge station, a harmonic power flow calculation meth- od that contains EV charge station model is put forward. By taking the IEEE - 33 node distribution system as an exam- ple, the harmonic power flow is calculated under different situations with 2 kinds of harmonic sources. From the result we can see that voltage distortion rate of panel point and ad- jacent nodes are increased after the modification of harmon-ic current. The connection of EV charge station to the net- work influences the power quality of the panel point and ad- jacent nodes.