Performance diagnosis method for fuel cell

Abstract

The invention discloses a performance diagnosis method for a fuel cell. The method comprises the following steps: introducing an impedance secant angular difference value delta alpha as a performancediagnosis judgment index of the fuel cell; using an improved electrochemical impedance spectroscopy method to solve to obtain the current impedance secant angle alpha t; at the same time, based on anestablished model, calculating to obtain a secant angle alpha 0 under the normal condition under the current density, temperature and humidity currently by a controller; and judging the current watermanagement state of the fuel cell by the controller according to the difference value delta alpha of the two secant angles, and generating a control signal to perform humidity adjustment on the fuel cell, so as to ensure that the fuel cell is in a normal working condition. The performance diagnosis method for the fuel cell provided by the invention can quickly and accurately judge the water management state of the fuel cell and recover the performance of the fuel cell under the condition of only using an alternating current signal generator and a data acquisition system, and improve the outputperformance of the fuel cell.

Description

Technical field: [0001] The invention relates to a performance diagnosis method of a fuel cell. Background technique: [0002] Driven by economic globalization, the world economy has developed by leaps and bounds. Energy shortages have restricted economic development, and energy issues have become a key problem that the world needs to solve urgently. At the same time, the environmental problems caused by the increasing consumption of traditional energy are also threatening the survival of human beings. At this time, it is urgent to develop new energy to replace traditional energy. Among all the alternatives to fossil fuels, fuel cells have become the most promising energy supply method due to their good operating performance and environmental friendliness for power generation. The proton exchange membrane fuel cell (Proton Exchange Membrane Fuel Cell, PEMFC) has the advantages of no pollution, zero noise and stable power, suitable for large-scale commercial development of h...

AI Technical Summary

Problems solved by technology

However, most of the auxiliary variables selected by the existing diagnostic methods are still the external characteristics of PEMFC, which cannot accurately feed back the internal working status of the stack.

At the same time, there is a certain error between the amount of water produced by the internal reaction of the stack obtained by modeling and the actual one, which will affect the accuracy of the diagnostic results.

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