This paper presents impedance-based analysis, mitigation, and power-hardware-in-the-loop (PHIL) demonstration of reactive power oscillations in a wind power plant using a 4-MW Type III wind turbine drivetrain. Because such low-frequency oscillations result from interactions among slower control loops of wind turbines regulating phasor quantities—active and reactive power output of the wind turbine and the magnitude of voltages at the point of interconnection (POI)—a new type of admittance is defined in terms of phasor quantities for their analysis. The so-called power-domain admittance of a wind turbine is defined as the transfer function from the frequency and magnitude of voltages at the POI to the active and reactive power output of the turbine. The power-domain admittance responses of the 4-MW wind turbine are measured using a 7-MVA grid simulator to identify the source of the reactive power oscillations. Power-domain impedance analysis and PHIL experiments are performed to explain how a resonant mode manifests as turbine-to-turbine and plant-to-grid reactive power oscillations. It is discovered that weaker grids exhibiting high inductive impedance mitigate oscillations in the reactive power output of wind power plants; however, a higher grid impedance does not help in damping turbine-to-turbine reactive power oscillations. This paper presents a simple droop-based solution to eliminate both turbine-to-turbine and plant-to-grid reactive power oscillations.

本文介绍了基于阻抗的分析，缓解和功率硬件在环（PHIL）演示，它使用4 MW III型风力涡轮机传动系统在风力发电厂中进行无功功率振荡。因为这种低频振荡是由风轮机的较慢控制回路之间的相互作用引起的，所以这些风轮机调节相量（风轮机的有功和无功功率输出以及互连点（POI）的电压大小），因此定义了一种新型的导纳根据相量进行分析。风力涡轮机的所谓功率域导纳定义为从POI处电压的频率和幅度到涡轮机有功和无功输出的传递函数。使用7-MVA电网模拟器测量4-MW风力发电机的功率域导纳响应，以识别无功功率振荡的来源。进行了功率域阻抗分析和PHIL实验，以解释谐振模式如何表现为涡轮机到涡轮机和工厂到电网的无功功率振荡。已经发现，表现出高电感阻抗的较弱电网减轻了风力发电厂无功功率输出中的振荡。但是，较高的电网阻抗无助于抑制涡轮机之间的无功功率振荡。本文提出了一种基于下垂的简单解决方案，可消除涡轮机对涡轮机和工厂对电网的无功功率振荡。进行了功率域阻抗分析和PHIL实验，以解释谐振模式如何表现为涡轮机到涡轮机和工厂到电网的无功功率振荡。已经发现，表现出高电感阻抗的较弱电网减轻了风力发电厂无功功率输出中的振荡。但是，较高的电网阻抗无助于抑制涡轮机之间的无功功率振荡。本文提出了一种简单的基于下垂的解决方案，可消除汽轮机对涡轮和电厂对电网的无功功率振荡。进行了功率域阻抗分析和PHIL实验，以解释谐振模式如何表现为涡轮机到涡轮机以及工厂到电网的无功功率振荡。已经发现，表现出高电感阻抗的较弱电网减轻了风力发电厂无功功率输出中的振荡。但是，较高的电网阻抗无助于抑制涡轮机之间的无功功率振荡。本文提出了一种简单的基于下垂的解决方案，可消除汽轮机对涡轮和电厂对电网的无功功率振荡。较高的电网阻抗无助于抑制涡轮机之间的无功功率振荡。本文提出了一种简单的基于下垂的解决方案，可消除汽轮机对涡轮和电厂对电网的无功功率振荡。较高的电网阻抗无助于抑制涡轮机之间的无功功率振荡。本文提出了一种简单的基于下垂的解决方案，可消除汽轮机对涡轮和电厂对电网的无功功率振荡。