【作者】 刘鑫；

【导师】 李欣然；

【作者基本信息】 湖南大学 ， 电气工程， 2021， 硕士

【摘要】 随着社会经济的发展和人民生活水平的提高,人类对能源的需求持续增长。电力能源作为一种最常用的能源,在人们的生产生活中扮演着十分重要的角色。由于用电负荷增加以及大规模的新能源建设并网,导致电网峰谷差异日益增大,电力系统供需失衡,从而加重了电网调峰的压力。传统调峰方式由于高成本、高耗能、利用率低等缺点已经难以满足现阶段电网的调峰需求。与此同时,随着现代技术的发展将储能逐渐配置到电网中,储能可以在负荷高峰时释放低谷期吸收储存的电量,减少峰谷差值并平滑负荷,也可因低储高发获得直接经济效益,在提升电力设备利用率、减少供电成本、消纳新能源等方面的间接获益。本文研究多储能电站协同调峰调度控制策略。首先介绍了储能发展和技术概况,以及储能作为优质调峰资源在示范工程中应用情况,并总结了储能辅助电网调峰在控制策略、优化运行、电源选型、经济性评估方面的研究现状,对现阶段储能调峰研究的局限性进行了分析。其次,研究了调峰用储能电源的选型。基于储能系统经济性模型的搭建,建立多类型电池储能的合作博弈模型,再通过迭代搜索法进行优化求解。最终决定采用锂离子电池与全钒液流电池作为调峰用储能系统的最优电池类型组合。然后,针对电力系统的调峰策略问题,首先阐述并对比了电池储能系统基于日前负荷预测的恒功率与变功率充放电控制策略。为了提高负荷预测精度并实现储能电量优化控制,提出基于扩展短期预测和动态优化的控制策略。文中详细阐述了三种不同控制策略的原理和控制步骤,结合某地区实际仿真算例,使用绝对峰谷差、峰谷差率、负荷变化标准差三个指标对储能调峰性能进行对比,总结各种策略的调峰效果与优势,证明了所提基于扩展短期预测和动态优化的控制策略的优越性。最后,对多储能电站协同调峰优化运行进行研究。建立了考虑发电机组运行成本、负载率均衡度的多目标优化模型,在发电机组、输电网络、储能电站等相关约束条件下,选用?-约束法对优化调度模型求解。最后将所建数学模型在PJM-5节点输电网络进行仿真,以两个储能电站(包括同一电站内锂离子电池和全钒液流电池两种不同类型储能)之间的协调运行为例,建立了考虑电池特性差异(在循环充放电次数、不同倍率放电效率方面)的协调分配策略,仿真结果验证了所提策略的有效性与优越性。更多还原

【Abstract】 With the development of social economy and the improve ment of people’s living standards,human demand for energy continues to grow.As one of the most commonly used energy,electric energy plays a very important role in people’s production and life.Due to the increase of power load and large-scale new energy construction,the peak valley difference of power grid is increasing day by day,and the supply and demand of power system is unbalanced,which aggravates the pressure of power grid peak shaving.The traditional peak shaving method has been difficult to m eet the peak shaving demand of the current power grid due to its high cost,high energy consumption and low utilization.At the same time,with the development of modern technology,energy storage is gradually allocated to the power grid.Energy storage can release the stored electricity during the peak load period,absorb the stored electricity during the low load period,reduce the peak valley difference and smooth the load.It can also obtain direct economic benefits due to low storage and high generation,and indirectly benefit from improving the utilization rate of power equipment,reducing power supply cost and absorbing new energy.This paper studies the control strategy of cooperative peak load regulation for multiple energy storage plants.Firstly,the development and technology of energy storage are introduced,and the application of energy storage as a high-quality peak shaving resource in the demonstration project is introduced.Then,the research status of energy storage assisted peak shaving in control strategy,optimal operation,power source selection and economic evaluation is summarized,and the limitations of current research on energy storage peak shaving are analyzed.Secondly,the selection of energy storage power supply for peak load reg ulation is studied.Based on the economic model of energy storage system,the cooperative game model of multi type battery energy storage is established,and then the iterative search method is used to optimize the solution.Finally,lithium-ion battery and vanadium redox battery are selected as the optimal combination of peak shaving energy storage system.Then,aiming at the peak load regulation strategy of power system,the constant power and variable power charge and discharge control strategies of batt ery energy storage system based on day ahead load forecasting are introduced and compared.In order to improve the accuracy of load forecasting and realize the optimal control of energy storage,a control strategy based on extended short-term forecasting and dynamic optimization is proposed.In this paper,the principle and control steps of three different control strategies are introduced in detail.Combined with the actual simulation example in a certain area,the peak to valley absolute difference,peak to valley difference rate and load variation standard deviation are used to compare the peak regulation performance of energy storage.The peak regulation effect and advantages of various strategies are summarized,and the advantages of the proposed control strategy based on extended short-term prediction and dynamic optimization are proved.Finally,the optimal operation of multi energy storage power stations is studied.A multi-objective optimization model considering the operation cost and load rate balance of power generation units is established.Under the constraints of power generation units,transmission network and energy storage station,the ?-constraint method is used to solve the optimization model.Finally,the mathemat ical model is simulated in PJM-5 node transmission network.Taking the coordinated operation of two energy storage power stations(including lithium-ion battery and vanadium redox battery in the same power station)as an example,the coordinated allocation strategy considering the differences of battery characteristics(in terms of cycle charge and discharge times and discharge efficiency at different rates)is established.The simulation results verify the effectiveness of the proposed method The effective ness and superiority of the proposed strategy.更多还原