风电并网电力系统小扰动稳定性灵敏度分析和控制措施优化

For the small-disturbance stability of wind power integrated power system, with the extended linearized power flow equation, the eigen-sensitivity to the operational/control parameters which change the initial operation point is proposed. Considering the linearization error of the state equation and the truncation error of the eigen-sensitivity, the successive linear programming (SLP) is applied to optimize the operational/control parameters. The conflicting constraints to different critical modes and different performance indices are searched and evaluated to determine the feasible region and the search step. With the non-linear constraint of the second-order eigenvalue sensitivity, the small-disturbance stability constrained optimal power flow model (SSC-OPF) of the wind power systems is proposed. The sensitivity of the optimized object to the steady-state and dynamic constraints, i.e. the cost of stability control, is decided by the Lagrange multipliers. The modes of the wind turbulence are decomposed to derive the dynamic model, which is included in the small-disturbance stability and optimization model. According to the time-frame of wind dynamics, the model order of the wind power system is reduced and the error is quantified. Considering the severity and the occurring possibility of the critical modes, the sensitivity to the operational/control parameters, and control cost, the composite evaluation, choice and ranking methods of the control measures are proposed. The accuracy of the proposed sensitivity and control optimization methods of the small-disturbance stability of wind power systems is validated by the large-disturbance time-domain simulation with the critical modes activated.

针对风电并网电力系统小扰动稳定性，拓展线性潮流方程，提出针对影响初始运行点的运行/控制参数的特征灵敏度算法。计及风电系统状态方程线性化和灵敏度截断误差，建立连续线性规划模型以优化运行/控制参数。对于不同危险模式和不同性能指标，搜索并评估相互冲突约束，确定可行解域和搜索步长。计及特征值二阶灵敏度非线性约束，提出含小扰动稳定性约束的风电系统最优潮流算法。由拉格朗日乘子确定优化目标对稳态/动态约束的灵敏度，量化稳定控制成本。分解阵风模式建立动态模型，将其引入风电系统小扰动稳定控制与优化算法。根据风速动态时间尺度，对风电系统模型降阶。量化降阶误差。综合危险模式严重程度、被激发可能性、对运行/控制参数灵敏度、控制成本，建立稳定控制措施的综合评估和选择排序方法。采用大扰动时域仿真，验证危险模式被激励后，所提风电系统小扰动稳定灵敏度分析和控制优化算法的正确性。

中文摘要(对项目的背景、主要研究内容、重要结果、关键数据及其科学意义等做简单概述，800字以内，含标点符号)：.与传统火电和水电机组不同，风电机组部分或全部经变流器并网，缺乏同步需求和稳定控制能力。大规模风电并网，降低电网稳定水平和抑制低频振荡能力。因此需要研究电网危险模式与SG/DFIG控制参数间关系，寻找有效预防控制措施。.本项目针对大规模风电并网电力系统功角稳定和低频振荡分析和控制问题展开研究。基于分步求导，提出小扰动稳定分析危险模式阻尼比对SG/DFIG控制参数灵敏度的解析表达。以潮流方程为桥梁，提出危险模式对节点有功/无功灵敏度的解析表达，进而提出基于ZIP可控负荷灵敏度的风电并网电力系统低频振荡模式抑制的新思路。为避免特征向量多解性，补充约束条件，提出特征向量对控制参数灵敏度的唯一解，进而提出电网机电模式机电回路相关比和危险模式可观性对SG/DFIG控制参数的解析灵敏度模型。为保证参与电网稳定控制DFIG安全，基于开环模型分析POD对DFIG负面影响，提出计及DFIG振荡约束的POD参数优化模型，协调抑制电网与DFIG振荡。建立电网危险模式对POD传递函数灵敏度，进而提出抑制多个危险模式的多通道附加阻尼控制器的控制策略，及其对控制参数的灵敏度模型。提出将风电并网系统危险模式阻尼比作为安全约束的电网小扰动稳定约束最优潮流，及其对控制参数可调范围灵敏度的解析表达。改进大扰动后功角振荡曲线对控制参数灵敏度的解析表达和优化算法。研究成果拓展了现有复杂电网稳定控制算法，有助于提高新能源并网电力系统的稳定水平。.在本项目资助下，培养毕业博士3人、硕士14人。发表(录用)SCI检索论文25篇，另外发表(录用)EI检索论文29篇。授权发明专利6项。