共查询到18条相似文献，搜索用时 187 毫秒
1.
A power system with proton exchange membrane fuel cells (PEMFC) was designed for thermal underwater glider.Heat generated by PEMFC is used as the propulsion power of the glider,and the electricity is used in the control and sensor system.An electric energy storage system (ESS) is required which possesses high power density with good cycle life.Ultracapacitors which exhibit high power density and cycle life are considered as energy storage devices.Simulations based on a specific voyage condition indicate that ESS with ultracapacitors has positive effects on reducing the output power demand of PEMFC and lightening the power system.Experimental results show that the state of charge (SOC) is related to the capacitance and resistance in ultracapacitor ESS. 相似文献
2.
INTRODUCTION Distributed cogeneration technology is a hot topic in electrical and energy industries (Ferguson and Ugursal, 2004). China’s need to limit the power usage in some places to meet the peak power demand in summer of recent years stimulated and supported increasing research on distributed generation tech- nologies. Fuel cells, as renewable energy sources, are considered one of the most promising sources of distributed electrical power. Operational fuel cell systems have perform… 相似文献
3.
Jun-yi LIANG Jian-long ZHANG Xi ZHANG Shi-fei YUAN Cheng-liang YIN 《浙江大学学报(A卷英文版)》2013,14(8):535-553
To solve the low power density issue of hybrid electric vehicular batteries, a combination of batteries and ultra- capacitors （UCs） could be a solution. The high power density feature of UCs can improve the performance of battery/UC hybrid energy storage systems （HESSs）. This paper presents a parallel hybrid electric vehicle （HEV） equipped with an internal combus- tion engine and an HESS. An advanced energy management strategy （EMS）, mainly based on fuzzy logic, is proposed to improve the fuel economy of the HEV and the endurance of the HESS. The EMS is capable of determining the ideal distribution of output power among the internal combustion engine, battery, and UC according to the propelling power or regenerative braking power of the vehicle. To validate the effectiveness of the EMS, numerical simulation and experimental validations are carried out. The results indicate that EMS can effectively control the power sources to work within their respective efficient areas. The battery load can be mitigated and prolonged battery life can be expected. The electrical energy consumption in the HESS is reduced by 3.91% compared with that in the battery only system. Fuel consumption of the HEV is reduced by 24.3% compared with that of the same class conventional vehicles under Economic Commission of Europe driving cycle. 相似文献
4.
INTRODUCTION The proton exchange membrane fuel cell(PEMFC)is a very promising power source for resi-dential and mobile applications due to its attractive features such as high power density,relatively low operating temperature,convenient fuel supply,long lifetime,etc.(Chalk et al.,2000;Lee and Mukergee,1998).Despite these advantages,commercialization of PEMFC is delayed mainly due to the high fabrica-tion cost.Bipolar plates,most commonly used among the PEMFC components,are the gra… 相似文献
5.
LIU Cheng-ze ZHU Xin-jian 《浙江大学学报(A卷英文版)》2006,7(11):1878-1885
INTRODUCTION Proton Exchange Membrane Fuel Cell (PEMFC) is being rapidly developed in recent years because of its compact structure, light weight, low working temperature and rapid startup characteristics. But its E-I characteristic curve reveals its decreasing per- formance when confronted with suddenly increasing power demand, and high cost also restrains the ap- plication of the fuel cell. So the hybrid power scheme is the most suitable selection presently. Most of researches on fu… 相似文献
6.
LI Wei ZHU Xin-jian CAO Guang-yi 《浙江大学学报(A卷英文版)》2007,8(5):734-740
This paper describes a solar photovoltaic fuel cell (PVEC) hybrid generation system consisting of a photovoltaic (PV) generator, a proton exchange membrane fuel cell (PEMFC), an electrolyser, a supercapacitor, a storage gas tank and power conditioning unit (PCU). The load is supplied from the PV generator with a fuel cell working in parallel. Excess PV energy when available is converted to hydrogen using an electrolyser for later use in the fuel cell. The individual mathematical model for each component is presented. Control strategy for the system is described. MATLAB/Simulink is used for the simulation of this highly nonlinear hybrid energy system. The simulation results are shown in the paper. 相似文献
7.
This paper discusses dynamic characteristics of proton exchange membrane fuel cell (PEMFC) under rapid fluctuation of power demand. Wavelet neural network is adopted in the identification of the characteristic curve to predict the voltage. The system control scheme of the voltage and power is introduced. The corresponding schemes for voltage and power control are studied. MATLAB is used to simulate the control system. The results reveal that the adopted control schemes can produce expected effects. Corresponding anti-disturbance and robustness simulation are also carried out. The simulation results show that the implemented control schemes have better robustness and adaptability. 相似文献
8.
Modelling and control PEMFC using fuzzy neural networks 总被引：1，自引：0，他引：1
INTRODUCTION With worldwide increase of air pollution and the environmental consciousness of governments,people have to look for new resources to mitigate the energy crisis and improve the present environmental status(Baschuk and Li,2000;Rowe and Li,2001).Fuel cells are highly efficient and environmentally clean electricity generators(Berning et al.,2002)that convert the chemical energy of a gaseous fuel directly into electrical energy and play an important role in solving the energy pro… 相似文献
9.
In light of the Ф-mapping method,the contribution of disclination linges to the free energy density of 2-dimensional liquid crystals is studied in the single-elastic constant approximation.It is pointed out that ,compared with the previous theory ,the free energy density can be divided into two parts.One is the usual distorted energy density of director field around the disclination lines.The other is the free endrgy density of the disclination lines themselves which is centralized at the disclination lines and topoligically quantized in a unit of 1/2kπ .The topological quantum numbers are determined by the Hopf indices and Brouwer degrees of the director field at the disclination lines,i.e.,the disclination strength.From the method of Lagrangian multipliers,the equilibrium equation and the molecular field of 2-dimensional liquid crystals are also obtained.It is shown that the physical meaning of the Lagrangian multiplier is just the distorted energy density. 相似文献
10.
INTRODUCTION With worldwide increase of air pollution and the environmental consciousness of governments, people have to look for new resources to mitigate the energy crisis and improve the present environmental status (Ferng et al., 2004; Rowe and Li, 2001). Fuel cells are highly efficient and environmentally clean electrical generators (Mann et al., 2000) that convert the chemical energy of a gaseous fuel directly into elec-tricity energy and play an important role in solving the prob… 相似文献
11.
To prevent the oxygen starvation and improve the system output performance, an adaptive inverse control (AIC) strategy is developed to regulate the air supply flow of a proton exchange membrane fuel cell (PEMFC) system in this paper.The PEMFC stack and the air supply system including a compressor and a supply manifold are modeled for the purpose of performance analysis and controller design. A recurrent fuzzy neural network (RFNN) is utilized to identify the inverse model of the controlled system and generates a suitable control input during the abrupt step change of external disturbances. Compared with the PI controller, numerical simulations are performed to validate the effectiveness and advantages of the proposed AIC strategy. 相似文献
12.
SUDHAKARAN M. AJAY-D-VIMALRAJ P. PALANIVELU T.G. 《浙江大学学报(A卷英文版)》2007,8(6):896-903
This paper presents an efficient and reliable genetic algorithm (GA) based particle swarm optimization (PSO) tech- nique (hybrid GAPSO) for solving the economic dispatch (ED) problem in power systems. The non-linear characteristics of the generators, such as prohibited operating zones, ramp rate limits and non-smooth cost functions of the practical generator operation are considered. The proposed hybrid algorithm is demonstrated for three different systems and the performance is compared with the GA and PSO in terms of solution quality and computation efficiency. Comparison of results proved that the proposed algo- rithm can obtain higher quality solutions efficiently in ED problems. A comprehensive software package is developed using MATLAB. 相似文献
13.
WANG Rui-min CAO Guang-yi ZHU Xin-jian 《浙江大学学报(A卷英文版)》2007,8(5):741-747
Model and simulation are good tools for design optimization of fuel cell systems. This paper proposes a new hybrid model of proton exchange membrane fuel cell (PEMFC). The hybrid model includes physical component and black-box com-ponent. The physical component represents the well-known part of PEMFC, while artificial neural network (ANN) component estimates the poorly known part of PEMFC. The ANN model can compensate the performance of the physical model. This hybrid model is implemented on Matlab/Simulink software. The hybrid model shows better accuracy than that of the physical model and ANN model. Simulation results suggest that the hybrid model can be used as a suitable and accurate model for PEMFC. 相似文献
14.
Particle swarm optimization (PSO) is an efficient, robust and simple optimization algorithm. Most studies are mainly concentrated on better understanding of the standard PSO control parameters, such as acceleration coefficients, etc. In this paper, a more simple strategy of PSO algorithm called θ-PSO is proposed. In θ-PSO, an increment of phase angle vector replaces the increment of velocity vector and the positions are decided by the mapping of phase angles. Benchmark testing of nonlinear functions is described and the results show that the performance of θ-PSO is much more effective than that of the standard PSO. 相似文献
15.
Control design is important for proton exchange membrane fuel cell （PEMFC） generator. This work researched the anode system ofa 60-kW PEMFC generator. Both anode pressure and humidity must be maintained at ideal levels during steady operation. In view of characteristics and requirements of the system, a hybrid intelligent PID controller is designed specifically based on dynamic simulation. A single neuron PI controller is used for anode humidity by adjusting the water injection to the hydrogen cell. Another incremental PID controller, based on the diagonal recurrent neural network （DRNN） dynamic identification, is used to control anode pressure to be more stable and exact by adjusting the hydrogen flow rate. This control strategy can avoid the coupling problem of the PEMFC and achieve a more adaptive ability. Simulation results showed that the control strategy can maintain both anode humidity and pressure at ideal levels regardless of variable load, nonlinear dynamic and coupling characteristics of the system. This work will give some guides for further control design and applications of the total PEMFC generator. 相似文献
16.
This paper presented a control design methodology for a proton exchange membrane fuel cell （PEMFC） generation system for residential applications. The dynamic behavior of the generation system is complex in such applications. A compre- hensive control design is very important for achieving a steady system operation and efficiency. The control strategy for a 60 kW generation system was proposed and tested based on the system dynamic model. A two-variable single neuron proportional-integral （PI） decoupling controller was developed for anode pressure and humidity by adjusting the hydrogen flow and water injection. A similar controller was developed for cathode pressure and humidity by adjusting the exhaust flow and water injection. The desired oxygen excess ratio was kept by a feedback controller based on the load current. An optimal seeking con- troller was used to trace the unique optimal power point. Two negative feedback controllers were used to provide AC power and a suitable voltage for residential loads by a power conditioning unit. Control simulation tests showed that 60 kW PEMFC generation system responded well for computer-simulated step changes in the load power demand. This control methodology for a 60 kW PEMFC generation system would be a competitive solution for system level designs such as parameter design, performance analysis, and online optimization. 相似文献
17.
In this paper, a 60 kW proton exchange membrane fuel cell (PEMFC) generation system is modeled in order to design the system
parameters and investigate the static and dynamic characteristics for control purposes. To achieve an overall system model,
the system is divided into five modules: the PEMFC stack (anode and cathode flows, membrane hydration, and stack voltage and
power), cathode air supply (air compressor, supply manifold, cooler, and humidifier), anode fuel supply (hydrogen valve and
humidifier), cathode exhaust exit (exit manifold and water return), and power conditioning (DC/DC and DC/AC) modules. Using
a combination of empirical and physical modeling techniques, the model is developed to set the operation conditions of current,
temperature, and cathode and anode gas flows and pressures, which have major impacts on system performance. The current model
is based on a 60 kW PEMFC power plant designed for residential applications and takes account of the electrochemical and thermal
aspects of chemical reactions within the stack as well as flows of reactants across the system. The simulation tests show
that the system model can represent the static and dynamic characteristics of a 60 kW PEMFC generation system, which is mathematically
simple for system parameters and control designs. 相似文献
18.
Particle swarm optimization （PSO） is an efficient, robust and simple optimization algorithm. Most studies are mainly concentrated on better understanding of the standard PSO control parameters, such as acceleration coefficients, etc. In this paper, a more simple strategy of PSO algorithm called θ-PSO is proposed. In θ-PSO, an increment of phase angle vector replaces the increment of velocity vector and the positions are decided by the mapping of phase angles. Benchmark testing of nonlinear functions is described and the results show that the performance of θ-PSO is much more effective than that of the standard PSO. 相似文献