双馈风电并网系统的宽频振荡机理分析与抑制

电力系统振荡失稳严重威胁其安全稳定运行,在“双碳”目标和能源转型的推动下,风电并网使新型电力系统的振荡稳定性问题加剧。综合考虑传动系统、风机变换器、锁相环、串联补偿等电力系统各部分,建立了双馈风电并网系统的精确化综合模型。在此基础上,基于模式分析法分析系统振荡模式与参与因子关系特性,确定引发系统振荡模式的强相关状态变量和主导因素,探究双馈风电并网电力系统的宽频振荡机理,并寻找振荡抑制方法。与传统模型相对比,并在Matlab软件平台进行仿真分析与验证。结果表明：所建模型及机理分析方法以更多的状态变量表征了更丰富的振荡模式信息,更详尽地解释了系统宽频振荡机理,并能有效消除振荡,提高系统阻尼,提升系统稳定性,为进一步研究和开发电力系统宽频振荡检测和抑制方法奠定理论基础。

Mechanism analysis and suppression of broadband oscillation in a DFIG wind power grid-connected system

Power system oscillation instability is a serious threat to the safe and stable operation of a power system. Driven by the "double carbon" goal and energy transformation, large-scale wind power grid connection has aggravated the oscillation stability problem of the new power system. In this paper, an accurate synthesis model of a doubly fed wind power grid connected system is established by considering all parts of the power system such as the drive system, wind turbine converter, phase-locked loop and series compensation. Then, based on the mode analysis method, the relationship between the system oscillation mode and the participation factors is analyzed. The strongly related state variables and dominant factors that cause the system oscillation mode are determined, and the broadband oscillation mechanism of the doubly fed wind power grid-connected power system is explored. The oscillation suppression method is found. To compare with the traditional model, simulation and verification are carried out on the Matlab software platform. The results show that the model and mechanism analysis method established represent more abundant oscillation mode information with more state variables, explain the system wide-band oscillation mechanism in more detail, and eliminate the oscillation, improving system damping and stability. It lays a theoretical foundation for further research and development of power system wide-band oscillation detection and suppression methods.