含大规模储能的多端直流输电系统协调控制策略

A Study on the Coordinated Control Strategy of the Multi-End DC Transmission System with Large-Scale Energy Storage

近年来,储能和直流输电系统作为大规模新能源发电并网、消纳和远距离传输的关键技术,得到了迅猛发展。然而,规模储能的接入增加了电网调度复杂性,对电网安全稳定带来挑战。为了解决上述难点,提出了含大规模储能的多端直流输电系统协调控制方法。首先,分析了可再生能源及储能并网模型,给出了风电、光伏及储能的控制策略;其次,提出了风、火、光、储多端直流输电系统的综合能源控制策略;最后,通过系统仿真,验证了文章所提控制策略的有效性。研究表明,基于所提控制策略,电网加入储能系统后,各种工况下受端电网功率波动范围均在±5%以内,系统达到稳定状态响应时间均小于0.5 s,使得受端电网具有快速调节能力,提高了新能源富集区域电网的稳定运行能力。

As the key technologies for large-scale new energy generation grid connection, consumption and longdistance transmission, energy storage and DC transmission systems have developed rapidly in recent years. However,the access of large-scale energy storage increases the complexity of grid dispatching and brings challenges to the security and stability of the grid. This paper studies the coordinated control strategy of the multi-terminal HVDC transmission system with large-scale energy storage connected to the grid. Firstly,the grid-connected models of renewable energy and energy storage are analyzed, and the control strategies of wind power,photovoltaics and energy storage are given;secondly, the comprehensive energy control strategy of wind, thermal,photovoltaic, and storage multi-terminal DC transmission systems is proposed. Finally,the simulation model of five-terminal DC transmission system is built in PSCAD/EMTDC,and the proposed strategy in this paper is verified by simulation.The research shows that,based on the proposed strategy,the power fluctuation range of the receiving-end power grid under various working conditions is within ±5%,and the response time is less than 0.5 s. It has the ability of rapid adjustment,which improves the stable operation ability of the power grid in the area rich in new energy.