The vanadium redox flow battery (VRB) is considered to be one of the most promising technologies for large-scale energy storage, with the electrolyte flow rate capable of significantly affecting the mass transfer, temperature rise, and pump power losses of the VRB system. Although the flow-rate optimization under constant current has been addressed in the literature, few studies have investigated the control strategy for the electrolyte flow rate under varying (dis-)charge power that is common in practical applications. Moreover, fewer studies have considered the concentration discrepancy of the active species in the tank and stack in the flow-rate optimization. In this paper, the electrolyte flow-rate optimization is investigated by incorporating the influences of the flow rate on the mass transfer, temperature rise, and required pump power. A transient model of the VRB system is developed to derive the total power losses (by which the overall system energy efficiency is determined; include losses resulting from overpotentials, ohmic drops, and required pump power) as a function of the applied current, concentration of the active species in the stack, and flow rate of the electrolyte. Based on this model, a dynamic flow-rate control strategy is proposed for determining the optimal flow rate under varying (dis-)charge power and state-of-charge conditions. The simulation results show that the proposed control strategy can deliver a high VRB system efficiency of 87.7%, and manage the electrolyte temperature to the safe range during mild summer days.

钒氧化还原液流电池（VRB）被认为是用于大规模能量存储的最有前途的技术之一，其电解液流速能够显着影响VRB系统的传质，温度上升和泵浦功率损耗。尽管文献中已经解决了恒定电流下的流量优化问题，但很少有研究研究在实际应用中常见的变化（放电）功率下电解质流量的控制策略。此外，很少有研究在流量优化中考虑到罐和烟囱中活性物质的浓度差异。在本文中，通过综合考虑流速对传质，温度升高和所需泵浦功率的影响，研究了电解液流速的优化方法。开发了VRB系统的瞬态模型，以得出总功率损耗（由此确定总体系统能效;包括由过电势，欧姆降和所需泵浦功率引起的损耗）与所施加电流，电池堆中的活性物质以及电解质的流速。基于该模型，提出了一种动态流量控制策略，用于确定在变化的（放电）功率和荷电状态下的最佳流量。仿真结果表明，所提出的控制策略在夏季温和的情况下可以提供高达87.7％的VRB系统效率，并将电解液温度控制在安全范围内。包括由过电势，欧姆降和所需的泵浦功率引起的损耗，这些损耗是所施加电流，电池堆中活性物质浓度和电解质流速的函数。基于该模型，提出了一种动态流量控制策略，用于确定在变化的（放电）功率和荷电状态下的最佳流量。仿真结果表明，所提出的控制策略在夏季温和的情况下可以提供高达87.7％的VRB系统效率，并将电解液温度控制在安全范围内。包括由过电势，欧姆降和所需的泵浦功率引起的损耗，这些损耗是所施加电流，电池堆中活性物质浓度和电解质流速的函数。基于该模型，提出了一种动态流量控制策略，用于确定在变化的（放电）功率和荷电状态下的最佳流量。仿真结果表明，所提出的控制策略在夏季温和的情况下可以提供高达87.7％的VRB系统效率，并将电解液温度控制在安全范围内。提出了一种动态流量控制策略，用于确定变化的（放电）功率和荷电状态条件下的最佳流量。仿真结果表明，所提出的控制策略在夏季温和的情况下可以提供高达87.7％的VRB系统效率，并将电解液温度控制在安全范围内。提出了一种动态流量控制策略，以确定在变化的（放电）功率和荷电状态下的最佳流量。仿真结果表明，所提出的控制策略在夏季温和的情况下可以提供高达87.7％的VRB系统效率，并将电解液温度控制在安全范围内。