复杂电能质量环境下的电力弹簧多目标协调控制研究及应用

With the rapid development of China's power grid, the increase in electricity consumption year by year, the electronization of electric equipment, unreasonable structure of the grid and the imperfect management have led to increasingly serious power quality problems on the user side. Meanwhile, a large number of renewable energy integrating in the network further complicates the power quality problem. As a new type of distributed reactive power compensation equipment, Electric spring (ES) can form active smart load with electric equipment, which provides targeted regulation for the voltage, frequency, harmonics and other power quality problems on the user side. Thus the electric spring has broad application prospects. However, the existing electric spring model has the disadvantages of single-purpose and low control precision, and the related application is not combined with the actual power grid. Based on the actual situation of the power grid, this project firstly aims to establish a multi-objective control strategy model of the electric spring by combining the comprehensive evaluation method of the power quality on the user side. Secondly, the modern nonlinear control method and the robust optimization algorithm are used to realize the efficient solution of the electric spring model. Lastly, the large-scale application of electric spring in the power grid is studied to work out a coordinated control method for the multi-electric spring system and the traditional reactive power compensation equipment. The research results can provide theoretical basis and technical support for the practical application of power spring in power grid.

目前在我国电网中，随着电力电子技术的快速发展及新能源的大规模并网，电能质量问题呈现复杂化的趋势，对用户侧的影响尤为严重。电力弹簧作为一种新型分布式无功补偿设备，可对用户侧各类电能质量问题提供针对性地治理。但现有的电力弹簧模型存在功能单一、控制精度较低的缺点，其相关应用亦未与实际电网相结合。为此，本项目基于电网的实际情况，开展了电力弹簧对复杂电能质量问题综合治理的研究，内容包括：结合用户侧的电能质量综合评估方法，考虑不同电能质量问题对用户的影响，建立电力弹簧的多目标控制策略模型，使其可以在不同工作模式之间进行切换；提出电力弹簧控制系统的参数优化方法，通过现代非线性控制方法及鲁棒优化算法，实现电力弹簧控制系统模型的高效求解；研究电力弹簧在电网中的大规模应用，构建系统中多电力弹簧以及与传统无功补偿设备的协调控制方法。研究成果可为电力弹簧在电网中的实际应用提供理论依据和技术支撑。

大规模分布式电源接入配电网，电网与用户供需互动日益频繁，使得配电网出现源荷智能化、网络电力电子化等新特征。配电侧的源、网、荷具有更强的时空不确定性，呈现出常态化的随机波动和间歇性。用户侧可以感知到的电能质量问题成为了电力电子化电力系统的新挑战。如何进行需求侧管理，发展主动型智能负载技术，保障配网安全可靠运行，已成为能源与电网领域的重大科学命题。.为了使主动型智能负载不仅支撑关键性负载的电压，还能改善系统的频率和波形，本文提出了针对主动型智能负载-电力弹簧的多目标控制策略。在控制策略中，集成了频率的控制和电压、无功功率的控制。以能够当电网电压降低时，切换到彻底的无功功率控制，以最大限度遏制电压的降低；加入频率的控制，以使在电机负载的启动快速同步（克服惯性对系统频率的影响），或者在孤岛电网时维持系统的频率稳定。.对于优化对频率、电压和功率的控制，本文借鉴了经典的下垂控制策略和虚拟同步机控制策略，对原本的基于电力弹簧的主动型智能负载的控制策略进行优化。所优化的控制策略的控制效果得到了很好的仿真和实验验证。