This article deals with a generalized second-order filter (GSOF) for a two-stage grid interfaced solar photovoltaic (PV) system at abnormal situations of dc offset, voltage unbalances and distortions, grid faults, variable PV array irradiation and grid voltage sags/swells. The prime objective of using this GSOF control is to extract positive sequence components from the unbalanced and distorted voltages and to supply PV array power to utility at improved power quality. An instinctive protection during grid faults is used. To achieve a quick dynamic performance, a term (feed-forward) in PV array power is implemented. The dc link voltage is controlled adaptively to reduce losses due to switching in the voltage source converter. The system with GSOF control is simulated and its performance is validated with test results on a system prototype for different operating states like voltage distortions, unbalances or swell/sag in the grid voltages and PV array insolation changes. The distortion in the grid voltages and currents is within the bounds, as recommended in the IEEE-519 standard.

中文翻译：

---

使用基于 GSOF 控制的三相并网住宅光伏系统

本文讨论了在直流偏移、电压不平衡和失真、电网故障、可变光伏阵列辐照和电网电压骤降等异常情况下用于两级并网太阳能光伏 (PV) 系统的广义二阶滤波器 (GSOF)/膨胀。使用这种 GSOF 控制的主要目的是从不平衡和失真的电压中提取正序分量，并以改善的电能质量为公用事业提供 PV 阵列电源。使用电网故障期间的本能保护。为了实现快速动态性能，在光伏阵列功率中实施了一项（前馈）。直流链路电压被自适应地控制以减少由于电压源转换器中的切换而引起的损耗。对具有 GSOF 控制的系统进行仿真，并通过系统原型上的测试结果验证其性能，这些测试结果适用于不同操作状态，如电网电压和光伏阵列日照变化的电压失真、不平衡或骤升/骤降。电网电压和电流的失真在 IEEE-519 标准建议的范围内。