含大规模风电场的电力系统随机稳定性分析

With the interconnection of the region grid, especially the incorporating of wind power and other renewable energy sources, the power grid has more intricate structure, wider geographic distribution, more and more components and complex dynamic behavior. It takes a great challenge for the security and stability of the power system due to the incorporation of large-scale wind power system. Because of the sudden and hidden accident, there is an urgent need for studying the stability mechanism of this kind of dynamic, static and uncertain super scale nonlinear hybrid power system from a point of theory and application view to improve the grid's stability. Based on the analysis of the influence on the full system of the synchronization power grid with large-scale wind turbines, the project intends to build the stability model of nonlinear hybrid dynamic system for the power grid containing large-scale wind farm. Then through interdisciplinary approaches among the power system analysis, scientific computation, stochastic mathematics, optimization theory, nonlinear analysis theory, the definition, classification and criterion for stability of the nonlinear stochastic hybrid dynamic system are proposed; Corresponding theoretical and numerical analyzing methods are constructed; The stability mechanism of the stochastic-deterministic coupling power system with large-scale wind farm is revealed combined theoretical and numerical approaches with simulations and experiments; Then the relevant measures and suggestions to meliorate the impacts of wind farms on the stability of the power system are proposed from a point of planning and designing. All these achievements can provide theoretical basis and methods of support for operation and control of power system with interconnection of large scale wind power system.

大区电网互联，特别是风电等可再生能源的联网使电网结构更复杂、分布地域更广、元件更多，动态行为也更复杂。大规模风电接入给电力系统的安全稳定运行带来了严峻的考验，由于事故的突发性和隐蔽性，迫切需要从理论和应用层面对这种具有动、静态和不确定性的超大规模非线性随机混成动力系统的稳定机理进行研究，以有效提高电网的稳定性。本项目拟从大规模风电机组并入同步电网对整个系统的影响入手，建立包含大规模风电场的电力系统非线性随机混成动力系统的稳定性模型。通过将电力系统分析、科学计算、随机数学、最优化理论、非线性分析等多学科交叉的方法，提出非线性随机混成动力系统的稳定性定义、分类及判据，构造相应的理论和数值分析方法，并结合仿真实验，揭示含大规模风电的随机-确定性耦合电力系统的稳定机理，从规划设计的角度提出改善风电场对大电网稳定性影响的相关措施建议，从而为大规模风电接入电力系统的运行和控制提供理论基础和方法支撑。

大规模风电接入电网导致常规电力系统耦合了大量具有随机波动性的非同步电源，使得现代电力系统转变为随机－确定性耦合电力系统。给电力系统的稳定性问题特别是常规电力系统的稳定分析理论和方法带来了新的挑战。经过三年的努力和系统研究，按照申请书的研究思路和技术路线，顺利完成了预定的研究计划。通过对含风电场的电力系统分析，主要在如下几个方面取得进展：.从影响风电场随机出力特性的主要因素出发，提出了包含风频分布模型、风速相关性模型和风电转换模型三部分的多风电场随机出力模型。从概率分析的角度，提出了电力系统振荡稳定裕度概率评估模型，并结合风电随机出力模型、振荡稳定裕度确定性求解模型和蒙特卡罗仿真对该模型进行了求解。为了实现对系统振荡稳定裕度的随机特征和风险水平的整体把握和完整认知，提出了概率指标和风险指标两类评估指标。考虑稳定性对可用输电能力的影响，提出了基于自助法的广义蒙特卡洛方法，大大提高了评估效率。考虑风功率的随机性，我们选用随机过程对其进行建模并将其作为随机激励，进而建立用随机微分方程描述的系统状态方程，然后应用拟不可积Hamilton随机平均法，通过最大Lyapunov指数判断系统的随机稳定性。同时通过联合概率密度研究了系统在有界随机激励下产生的非线性随机响应、随机分岔等。. 本项目在 International Journal of Electrical Power and Energy System 、 Applied Mathematics and Computation等国际期刊和国际会议上发表论文 5 篇，另外有3篇论文已投IEEE Transactions on Power System以及IEEE Transactions on Smart Grid等国际著名期刊在审。