大中型光伏电站并网性能测试技术研究

Research on Grid-connecting Performance of Large and Medium Scale PV Power Station

以青海省某大型光伏电站的并网性能现场测试为例,研究大中型光伏电站并网性能测试技术。介绍了测试项目中电能质量测试和低电压穿越(LVRT)性能测试的现场试验方法,并对测试结果进行分析,得出结论:电能质量测试中电流直流分量和电压不平衡度超标,不符合并网要求;LVRT性能测试中,测试点输出三相电流在电压跌落故障发生和恢复时刻存在暂态现象:被测并网逆变器能在电压跌落故障期间保持不脱网,且能向电网提供一定的无功功率补偿,其LVRT性能符合并网标准要求。

Take grid-connecting performance test of a photovoltaic （PV） power station for instance, research on the test technology on large-scale grid-tied station and power quality testing and low voltage ride-through（LVRT） testing methods are introduced.The main results are given out and the analyses are as followed：current DC component and voltage unbalance degree are excessed in power quality test, so the PV station needs to be tested again until all the parame- ters meet the requirements.Three-phase currents have transient phenomenon when low voltage fault begin to happen or recover to the normal state.The PV inverter keep in connected with the grid all through the fault, and even provide a certain amount of reactive power compensation to the grid during the fault, thus the PV station＇s LVRT capability meets the grid-connecting standard requirements.