To optimize the operating efficiency and extend the lifespan of the multistack fuel cell hybrid system(MFCHS),this paper proposes a two-layer multiobjective optimal energy management strategy that considers the degrad...To optimize the operating efficiency and extend the lifespan of the multistack fuel cell hybrid system(MFCHS),this paper proposes a two-layer multiobjective optimal energy management strategy that considers the degradation of the fuel cell and the battery.Regarding the issues that power fluctuations damage the fuel cells'lifespan and high-current charging and discharging lead to battery capacity decay,the first layer of the strategy adopts locally weighted scatterplot smoothing(LOWESS)to smooth the output power of the fuel cells and prevent the battery from operating under high-current conditions.The second layer considers the uneven degree of degradation among the fuel cells and employs the dandelion optimizer(DO)algorithm to solve the objective function with an aging adaptive factor,optimizing the efficiency and lifespan.Meanwhile,the DO algorithm is enhanced by tent chaotic mapping and differential variation to improve the convergence speed and accuracy.Compared with the equivalent hydrogen consumption minimization strategy(ECMS)and the equal distribution strategy,the proposed strategy improves the average operating efficiency of the fuel cells,effectively reduces the degradation of the fuel cells and the capacity degradation of the battery,and maintains the performance consistency among the fuel cells.展开更多
A single-pole four-throw(SP4T)RF switch with charge-pump-based controller is designed and implemented in a commercial 130-nm silicon-on-insulator(SOI)CMOS process.An improved body self-biasing technique based on diode...A single-pole four-throw(SP4T)RF switch with charge-pump-based controller is designed and implemented in a commercial 130-nm silicon-on-insulator(SOI)CMOS process.An improved body self-biasing technique based on diodes is utilized to simplify the controlling circuitry and improve the linearity.A multistack field-effect-transistor(FET)structure with body floating technique is employed to provide good power-handling capability.The proposed design demonstrates a measured input 0.1-d B compression point of 38.5 d Bm at 1.9 GHz,an insertion loss of 0.27 d B/0.33 d B and an isolation of 35 d B/27 d B at 900 MHz/1.9 GHz,respectively.The overall chip area is only 0.49 mm^2.This RF switch can be used in GSM/WCDMA/LTE frontend modules.展开更多
基金supported by the Postgraduate Research and Practice Innovation Program of Jiangsu Province(Grant No.SJCX24_0161)the National Natural Science Foundation of China(Grant Nos.61374153 and 61403199).
文摘To optimize the operating efficiency and extend the lifespan of the multistack fuel cell hybrid system(MFCHS),this paper proposes a two-layer multiobjective optimal energy management strategy that considers the degradation of the fuel cell and the battery.Regarding the issues that power fluctuations damage the fuel cells'lifespan and high-current charging and discharging lead to battery capacity decay,the first layer of the strategy adopts locally weighted scatterplot smoothing(LOWESS)to smooth the output power of the fuel cells and prevent the battery from operating under high-current conditions.The second layer considers the uneven degree of degradation among the fuel cells and employs the dandelion optimizer(DO)algorithm to solve the objective function with an aging adaptive factor,optimizing the efficiency and lifespan.Meanwhile,the DO algorithm is enhanced by tent chaotic mapping and differential variation to improve the convergence speed and accuracy.Compared with the equivalent hydrogen consumption minimization strategy(ECMS)and the equal distribution strategy,the proposed strategy improves the average operating efficiency of the fuel cells,effectively reduces the degradation of the fuel cells and the capacity degradation of the battery,and maintains the performance consistency among the fuel cells.
文摘A single-pole four-throw(SP4T)RF switch with charge-pump-based controller is designed and implemented in a commercial 130-nm silicon-on-insulator(SOI)CMOS process.An improved body self-biasing technique based on diodes is utilized to simplify the controlling circuitry and improve the linearity.A multistack field-effect-transistor(FET)structure with body floating technique is employed to provide good power-handling capability.The proposed design demonstrates a measured input 0.1-d B compression point of 38.5 d Bm at 1.9 GHz,an insertion loss of 0.27 d B/0.33 d B and an isolation of 35 d B/27 d B at 900 MHz/1.9 GHz,respectively.The overall chip area is only 0.49 mm^2.This RF switch can be used in GSM/WCDMA/LTE frontend modules.
文摘针对电氢耦合系统运行时单体燃料电池输出功率有限和工作效率低难以维持系统在复杂工况下稳定运行的问题,研究了多堆燃料电池系统(multi-stack fuel cell system,MFCS)功率分配策略,提出了一种计及多堆燃料电池功率分配的电氢耦合分层能量管理策略,将控制系统分为状态机控制层和设备控制层。以燃料电池运行效率最优为目标设计了多堆燃料电池功率分配方法,上层为状态机控制层,采集系统剩余功率、锂电池荷电状态(state of charge,SOC)和储氢罐氢状态(state of hydrogen,SOH),并将系统状态分为8种,下层为设备控制层,接收状态机发送的开关信号控制各设备选择不同的控制模式运行,使燃料电池尽可能运行于正常区间,提高燃料电池寿命和工作效率,减少系统运行状态的切换、提升电氢耦合系统抗扰动能力和光伏利用效率。基于Simulink平台仿真验证了所提分层控制策略的正确性。
