大规模风电柔直并网系统输电能力评估与源网协调研究

The reliable integration into power system and well accommodation of large-scale wind power with intermittence and randomness has become a key problem and difficulty of security and stability operation and dispatching of power grid. Focused on the theme of the integration and accommodation of large-scale wind power into power system, this project develops technology research on the evaluation and coordination control for the regional system transmission capability when the large scale of the wind power is integrated into the power grid based on VSC-HVDC. Firstly, construct the VSC-HVDC system model and analysis method suitable for the integration of large-scale wind power. Then, based on spatio-temporal analysis coupling mechanism of large-scale wind power, study the impact of the integration of large-scale wind power into power system on transmission capability margin and quantitative criteria of the margin, and construct the model of evaluation and decision for the regional system transmission capability under the condition of accommodation of wind power of priority. Finally, combining the operating characteristics of VSC-HVDC system, study the coordination control strategy of converter station based on system-level control, perfect the stability control plan of the whole system under the condition of disturbance. This subject provides analysis method and decision-making basis for scientifically coordinating the relationship of the economic goals and the security of the system, realizing the win-win of the wind power utilization and the security and economic operation of the power system, improving the transmission capability of the power system and ensuring the security and efficient operation of the system.

如何将具有间歇性和随机性的大规模风电可靠接入系统并将其良好消纳，已成为电网安全稳定运行和调度的关键问题和难点。本项目紧紧围绕电力系统大规模风电接入与消纳这一主题，开展基于VSC-HVDC技术接入的大规模风电并网系统区域间输电能力评估与源网协调控研究。首先，构建适用于大规模风电接入的VSC-HVDC系统模型及分析方法；然后，在剖析大规模风电出力的时空耦合机理的基础上，研究大规模风电并网对输电能力裕度的影响和裕度量化准则，并构建风电优先消纳条件下系统区域间输电能力评估与决策模型；最后，结合VSC-HVDC输电系统的运行特性研究基于系统级控制的换流站协调控制策略，完善扰动条件下全系统稳定运行控制方案。本课题的研究为科学地协调好系统运行经济性与安全性的关系，实现大规模风电良好消纳和电网安全经济运行的双赢，提高电力系统输电能力及确保系统高效运行提供科学的分析手段与决策依据。

随着电力系统的发展，以风电为代表的高比例可再生能源和柔性直流输电VSC-HVDC技术给电力系统可用输电能力(Available Transfer Capability, ATC)分析与计算带来了新的挑战。本项目针对基于VSC-HVDC技术接入的大规模风电并网系统区域间输电评估与源网协调问题开展了深入的研究工作。.项目的主要研究内容和完成情况包括：（1）基于历史数据和风电的概率分布特性，计及风电场内部和风电场间的影响，建立了计及相关性的大型风电场不确定性输出功率的数学模型，并基于拉丁超立方采样法进行仿真模拟。（2）综合整合发、用电侧旋转备用资源，将弃风、可中断负荷分别作为部分负、正旋转备用考虑到发电调度模型中，并提出基于可靠性指标（缺电时间期望指标）的区域电网容量效益裕度（CBM）概率性计算模型；（3）以电力系统经济调度为下层模型，以ATC评估模型为上层模型，提出一种电力市场下的双层ATC优化模型，并将其转化为混合整数规划问题以便于求解。（4）构建基于端口能量的全系统能量函数，通过迭代势能边界面法（IPEBS）进行暂态稳定评估，提出一种基于端口能量的含电压源换流器型高压直流输电VSC-HVDC的交直流混合系统暂态稳定评估方法。（5）针对含柔性直流输电VSC-HVDC的交直流系统电压稳定性问题，开发出一种适用于含 VSC-HVDC的交直流系统连续潮流程序，以负荷裕度指标分析VSC-HVDC系统有功功率传输方向、有功功率传输容量及换流站与交流系统无功功率交换量的变化对系统电压稳定性的影响。.本项目积极探索了高比例风电并网背景下含VSC-HVDC的交直流混合系统可用输电能力的问题，研究了计及风电和需求侧资源的可用输电能力的评估模型与方法以及VSC-HVDC的稳定性评估方法。为电力系统可用输电能力评估和VSC-HVDC的协调控制提供了理论支撑。