Efficient thermal management of lithium-ion battery,working under extremely rapid charging-discharging,is of widespread interest to avoid the battery degradation due to temperature rise,resulting in the enhanced lifes...Efficient thermal management of lithium-ion battery,working under extremely rapid charging-discharging,is of widespread interest to avoid the battery degradation due to temperature rise,resulting in the enhanced lifespan.Herein,thermal management of lithium-ion battery has been performed via a liquid cooling theoretical model integrated with thermoelectric model of battery packs and single-phase heat transfer.Aiming to alleviate the battery temperature fluctuation by automatically manipulating the flow rate of working fluid,a nominal model-free controller,i.e.,fuzzy logic controller is designed.An optimized on-off controller based on pump speed optimization is introduced to serve as the comparative controller.Thermal control simulations are conducted under regular operating and extreme operating conditions,and two controllers are applied to control battery temperature with proper intervals which is conducive to enhance the battery charge-discharge efficiency.The results indicate that,for any operating condition,the fuzzy logic controller shows excellence in terms of the tracking accuracy of set-point of battery temperature.Thanks to the establishment of fuzzy set and fuzzy behavioral rules,the battery temperature has been throughout maintained near the set point,and the temperature fluctuation amplitude is highly reduced,with better temperature control accuracy of~0.2℃(regular condition)and~0.5℃(extreme condition)compared with~1.1℃(regular condition)and~1.6℃(extreme condition)of optimized on-off controller.While in the case of extreme operating condition,the proposed optimized on-off controller manifests the hysteresis in temperature fluctuation,which is ascribed to the set of dead-band for the feedback temperature.The simulation results cast new light on the utilization and development of model-free temperature controller for the thermal management of lithium-ion battery.展开更多
为了解决冰蓄冷中央空调存在的板换堵塞问题,提出了以制冰板换回水温度为控制变量,采用模糊控制预热变频泵流量的方法,以实现制冰快速性和可靠性的解决方案.设计了预热泵流量模糊控制器,研制了制冰板换防堵塞的预热回路;采用离线计算与...为了解决冰蓄冷中央空调存在的板换堵塞问题,提出了以制冰板换回水温度为控制变量,采用模糊控制预热变频泵流量的方法,以实现制冰快速性和可靠性的解决方案.设计了预热泵流量模糊控制器,研制了制冰板换防堵塞的预热回路;采用离线计算与在线查询相结合的方法,对基于西门子可编程逻辑控制器(PLC)的冰蓄冷中央空调系统进行了试验研究,给出了制冰板换回水温度控制结果,并对该模糊控制结果与传统的PID控制结果进行了比较.试验结果表明:在环境温度为28℃时,采用模糊控制调节制冰板换回水温度,其下降时间为90 m in,调节时间为158 min,稳态误差为0.26℃.该方案为智能化冰蓄冷中央空调稳定运行提供了依据.展开更多
基金supported by the National Key R&D Program of China(2021YFB3803200)the National Natural Science Foundation of China(Grant No.U2241253)。
文摘Efficient thermal management of lithium-ion battery,working under extremely rapid charging-discharging,is of widespread interest to avoid the battery degradation due to temperature rise,resulting in the enhanced lifespan.Herein,thermal management of lithium-ion battery has been performed via a liquid cooling theoretical model integrated with thermoelectric model of battery packs and single-phase heat transfer.Aiming to alleviate the battery temperature fluctuation by automatically manipulating the flow rate of working fluid,a nominal model-free controller,i.e.,fuzzy logic controller is designed.An optimized on-off controller based on pump speed optimization is introduced to serve as the comparative controller.Thermal control simulations are conducted under regular operating and extreme operating conditions,and two controllers are applied to control battery temperature with proper intervals which is conducive to enhance the battery charge-discharge efficiency.The results indicate that,for any operating condition,the fuzzy logic controller shows excellence in terms of the tracking accuracy of set-point of battery temperature.Thanks to the establishment of fuzzy set and fuzzy behavioral rules,the battery temperature has been throughout maintained near the set point,and the temperature fluctuation amplitude is highly reduced,with better temperature control accuracy of~0.2℃(regular condition)and~0.5℃(extreme condition)compared with~1.1℃(regular condition)and~1.6℃(extreme condition)of optimized on-off controller.While in the case of extreme operating condition,the proposed optimized on-off controller manifests the hysteresis in temperature fluctuation,which is ascribed to the set of dead-band for the feedback temperature.The simulation results cast new light on the utilization and development of model-free temperature controller for the thermal management of lithium-ion battery.
文摘为了解决冰蓄冷中央空调存在的板换堵塞问题,提出了以制冰板换回水温度为控制变量,采用模糊控制预热变频泵流量的方法,以实现制冰快速性和可靠性的解决方案.设计了预热泵流量模糊控制器,研制了制冰板换防堵塞的预热回路;采用离线计算与在线查询相结合的方法,对基于西门子可编程逻辑控制器(PLC)的冰蓄冷中央空调系统进行了试验研究,给出了制冰板换回水温度控制结果,并对该模糊控制结果与传统的PID控制结果进行了比较.试验结果表明:在环境温度为28℃时,采用模糊控制调节制冰板换回水温度,其下降时间为90 m in,调节时间为158 min,稳态误差为0.26℃.该方案为智能化冰蓄冷中央空调稳定运行提供了依据.
