Study on Performance Simulation of PEMFC and Reduced-order Method of PDE Model
|Course||Power Engineering and Engineering Thermophysics|
|Keywords||Proton exchange membrane fuel cell Modeling and Simulation Relative humidity Steady-state model Dynamic model|
Fuel cells have been recognized as the 21st century, one of the ways the new clean power generation. With energy demand and environmental requirements under the dual pressure, fuel cell research and application ushered in a good development opportunities. Fuel cells as a way to chemical energy efficient, environmentally friendly converted to electricity plant, as compared with the traditional thermal power, high efficiency, low noise, pollution, feed wide, versatile, and other prominent advantages . Proton exchange membrane fuel cell developed as a fifth-generation fuel cell relative to other cells, it has an operating temperature minimum, the highest specific energy to start the fastest, longest life, the most widely used features, more and more attention. By means of experiment or simulation studies of proton exchange membrane fuel cells affect the performance of a variety of factors, of which the simulation mode is a convenient, simple, effective means. Based on a modular modeling idea, through modeling and simulation to study the proton exchange membrane fuel cell steady-state and dynamic performance. This paper is divided into four parts, the first to establish H 2 / air-and H 2 / O 2 -type proton exchange membrane fuel cell units steady-state mathematical model, steady-state model considers the oxidant air or pure oxygen, respectively, to the fuel cell performance, taking into account the proton exchange membrane fuel cell humidifier, the relative humidity on the fuel cell performance. Established H 2 / air type dynamic mathematical model of the fuel cell, including the humidification case, considering the resultant vapor of the cathode-side dynamic properties of the fuel cell, including water vapor in the cathode channel and phase change latent heat generated. Secondly, according to the established steady-state mathematical model, using Matlab / Simulink established H 2 / air-and H 2 / O 2 -type Proton exchange membrane fuel cell simulation model. Through simulation, analysis of temperature, pressure, relative humidity on fuel cell performance, and compares the two types of battery performance. Simulation results show that: Improves fuel cell operating temperature and pressure can improve the performance of the battery output, relative humidity have a major impact on the battery, H 2 / O 2 -type cell output voltage , power, and efficiency is higher than under the same conditions H 2 / air fuel cells. Third, according to the established dynamic mathematical model, using Matlab / Simulink established H 2 / air proton exchange membrane fuel cell dynamic simulation model. Study of proton exchange membrane fuel cell current density occurs in step dynamics, the fuel cell stack body temperature, the temperature of the anode channel, cathode channel temperature, polar passage pressure, voltage, power, efficiency, and two-channel inlet, outlet, and internal hydrogen Oxygen, nitrogen, water quality dynamic changes. Simulation results show that, the amount of response time and the variation of the transition. And in order to control the temperature of the main body of the fuel cell stack, the cooling water flow step of dynamic process, the cell stack output voltage, power, efficiency, and the temperature of three parts, the poles of the channel and the dynamic pressure. Finally, for a more detailed analysis of proton exchange membrane fuel cell performance, partial differential equations are often used to create a proton exchange membrane fuel cell distributed parameter model for simulation and optimal control, resulting calculation speed decreases. Therefore, the conditions for partial differential equations with constraints (PDE) model calculations and optimal control real-time requirements and huge memory overhead problem, a reduced-order model based on the input / state constrained optimal real-time control method, in order to follow-up on the proton exchange membrane fuel cell distributed parameter model. Based on the proton exchange membrane fuel cell system modeling, simulation study for the battery system design, operation, optimization, control provides a theoretical basis, has a certain theoretical and practical significance.