摘要
全钒液流电池是具有良好应用前景的大规模储能技术之一,是解决电网调峰调频、间歇性可再生能源消纳等问题的有效手段。使用MATLAB基于自放电效应建立了全钒液流电池的电化学模型,研究了电池的充/放电形式和电解液流量对电池性能的影响规律,进而建立了微网负荷的优化调度模型,并提出了一种微网中逐时响应需求侧负荷波动的最优电解液流量计算流程和优化运行方法。研究结果表明:全钒液流电池的过电势损耗与电流正相关;随着电池的电解液流量从0.024 m^3/h增加至0.288 m^3/h,泵功相应由0.027 W增加至0.422 W,同时电池浓差极化损失的减小导致系统能量效率的提升;恒定负荷下,选取合适的电池电解液流量可获得较高的系统效率;采用提出的全钒液流电池优化运行方法,可实现微网变负荷工况下电池电解液流量的实时优化控制,相较于恒定流量的运行方法,电池的系统效率可提升至87.03%。
The vanadium redox flow battery(VRB) is considered to be one of the most promising technologies for large-scale energy storage, as well as an effective method to solve the problems of peak regulation and frequency modulation of power grid and promote the consumption of intermittent renewable energy. In this study, the electrochemical model of the VRB system is formulated using MATLAB based on self-discharge effect to investigate the effect of the charge/discharge process and electrolyte flow rate on the battery performance of the VRB system. Furthermore, an optimized scheduling model for the load in a microgrid is formulated. An optimal electrolyte flow calculation model for real-time response to the demand side load fluctuations in a microgrid is also constructed, and an optimized operation method of the VRB system is proposed. Simulation results show that the overpotential loss of vanadium battery correlates positively with the current. When the electrolyte flow rate of the VRB system increased from 0.024 m^3/h to 0.288 m^3/h, the pump power consumed by the battery increased from 0.027 W to 0.422 W, resulting in an increase in the energy efficiency. Higher system efficiencies can be obtained under constant loads by selecting the appropriate electrolyte flow rate of the VRB system. The proposed optimized operation method of the VRB system can be employed to realize real-time optimal control of battery electrolyte flow in a microgrid under variable load conditions. Unlike the constant flow operation method, the system efficiency of the battery can be increased to 87.03% using the optimized operation method.
作者
倪经纬
李明佳
NI Jingwei;LI Mingjia(Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education,School of Energy&Power Engineering,Xi'an Jiaotong University,Xi'an 710049,Shaanxi Province,China)
出处
《全球能源互联网》
2019年第6期608-616,共9页
Journal of Global Energy Interconnection
基金
国家自然科学基金项目(51806165).
关键词
全钒液流电池
电解液流量
系统效率
负荷响应
优化运行方法
vanadium redox flow battery
electrolyte flow rate
system efficiency
load response
optimized operation method
作者简介
倪经纬(1996),男,博士研究生,研究方向为全钒液流电池,E-mail:nijingwei@stu.xjtu.edu.cn;通信作者:李明佳(1990),女,博士,教授,研究方向为能源的高效利用、新能源及储能技术等,E-mail:mjli1990@xjtu.edu.cn。
