面向智能电网的广域阻尼控制(WADC)研究

With the construction of ultra-high voltage (UHV) power grid and the grid connection of a large number of renewable energy generation, it is urgent for the power system based on wide area measurement system (WAMS) to move toward smart power grid with wide area control system (WACS). The length of time delay with phasor measurement unit (PMU) signals maybe varies in a relatively wide range with the interconnection of regional power grids, and there are more uncertainties in power system after the grid connection of renewable energy generation like wind power and solar power. Therefore the problem of time delay and system uncertainties must be well dealt with for wide area damping control (WADC) in smart power grid. First, the feature of time delay is analyzed, and the statistical probability model is built for uncertain and random time delays. Then, time delay compensation methods for power system dynamic signals measured from PMUs are studied based on advanced signal analysis theory. The time delay robust damping controller for power oscillation on inter-area tie-lines is designed based on online identification of system model to make up the incomplete time delay compensation. Finally, specific indices are defined and comprehensive evaluation strategies for practical applications are discussed for the compensation degree of time delay and the control performances of WADC to damp inter-area power oscillation. The research work of this project is focused on the technology of random time delay compensation and adaptive time delay robust control within WADC of power systems; however the research findings are also applicable to other fields of wide area control involving PMU signal feedback.

随着特高压电网的建设和大量新能源发电的并网，电力系统广域测量系统(WAMS)亟待向智能电网广域控制系统(WACS)发展。区域电网互联使同步相量测量单元(PMU)信息时延可能在较大范围内变化，风电、光电等新能源发电并网则使电力系统的不确定因素增多，面向智能电网的广域阻尼控制(WADC)必须妥善处理时延和系统不确定因素问题。本项目首先分析PMU信息时延特性，建立不确定随机时延的统计概率模型；然后，研究基于先进信号分析理论的PMU信息时延补偿方法，以及基于系统模型在线辨识技术的区间联络线功率振荡时滞鲁棒阻尼控制器以弥补时延补偿不完全；最后，定义时延补偿度和电网区间联络线功率振荡阻尼控制性能的具体指标,并研究实际应用的综合评估方法。本项目的研究工作紧密围绕电力系统WADC中的随机大时延补偿技术和自适应时滞鲁棒控制技术展开，研究成果也可应用于涉及PMU信息反馈的其它广域控制领域。

特高压电网的快速建设、新能源发电和电动汽车等柔性负荷的大规模并网，对于电力系统的稳定分析与运行控制提出了新的挑战和更高要求，电力系统广域测量系统(WAMS)亟待向智能电网广域控制系统(WACS)发展。区域电网远距离互联、通信网络拥堵使同步相量测量单元(PMU)信息时延可能在较大范围内变化，风力和光伏发电的大量并网、电动汽车的大规模应用则使电力系统的不确定因素增多，面向智能电网的广域阻尼控制(WADC)必须妥善处理随机时延和系统不确定因素的影响。.本项目首先基于实际电网WAMS中的相量测量单元（PMU）信息时延数据，建立了随机时延模型，提出了基于信号预测技术的时延补偿方法；针对随机时延现象，提出了基于“时延匹配”思想的广域阻尼器设计方法和基于“最佳时延”思想的随机无序时延PMU信号预处理方法；基于相位偏移和反馈增益统一补偿的思想，提出了广域时滞电力系统稳定器（PSS）的结构和设计方法；考虑到实际电力系统时变、非线性的特点，还提出了时滞自适应控制策略和具有冗余设计的广域阻尼控制结构；此外，还在REG和微电网建模与并网控制、区块链技术等前瞻性领域开展了部分研究工作，为后续含高渗透率新能源的智能电网运行与控制技术研究奠定了基础。.本项目最重要的研究成果是阐明了WADC应用中“反馈信号的时延是中性的”的观点，并基于此提出了随机时延PMU信号预处理方法以及时延匹配控制策略，取得了显著的阻尼控制效果。此外，本项目阻尼控制研究主要是基于目前工程应用最广泛、最成熟的经典PSS结构和比例-积分-微分（PID）结构，所提的控制参数设计方法原理简单、适合实际工程应用。