光伏电站中性点接地方式的选择

Selection of Neutral Grounding Mode for Photovoltaic Power Station

合理的选择光伏电站中性点接地方式,是保证光伏电站安全、稳定、可靠运行的一个重要措施。理想的中性点接地方式能快速抑制故障,并防止故障范围的扩大。本文详细的比较了中性点不接地、中性点经消弧线圈接地、中性点经高电阻接地、中性点经小电阻接地四种方式的优缺点,并根据光伏电站电容电流较大的特点,选择中性点经小电阻接地的方式,并通过实例计算接地电阻值的选择和接地变压器容量的配置。

Reasonable selection of neutral grounding mode for photovoltaic power station that is an important measure to ensure the safe,stable,reliable operation of photovoltaic power station.The ideal neutral grounding mode can quickly suppress the fault and prevent the expansion of the fault range.In this paper,the advantages and disadvantages of four methods are compared in detail:ungrounded neutral point,grounded neutral point through arc suppression coil,grounded neutral point through high resistance and grounded neutral point through small resistance.According to the characteristics of large capacitance current of photovoltaic power station,the method of grounded neutral point through small resistance is selected,and the selection of grounding resistance value and the configuration of grounding transformer capacity are calculated through examples.