Method and device for controlling the shutdown of electrical production from a fuel cell

Abstract

Method and device for controlling the shutdown of electrical production in a fuel cell. The invention relates to a method for controlling the shutdown of electrical production in a fuel cell by effectively controlling the opening of the overall bypass circuit and the local bypass circuits during the transient shutdown phase, thereby ensuring a rapid and homogeneous discharge of all individual cells during the shutdown phase. Figure for the abstract: Fig. 1

Claims

if said overall bypass shutdown criterion is met, b) a local electrical discharge step comprising the implementation of at least one local electrical discharge cycle comprising b1) the closure of each local bypass electrical circuit in which the average voltage of said at least one of the corresponding cell modules is greater than the Uprt protection voltage so as to divert the electric current produced by said cell module into the corresponding local bypass load, and b2) the gradual opening of each local bypass electrical circuit closed in step b1) in which the average voltage of said at least one of the corresponding cell modules is less than the Uprt protection voltage,in order to stop the drift of electric current produced by said cell module in the corresponding local bypass load and the end of the electrical discharge sequence is reached when each of the local bypass electrical circuits closed in step bl) has been opened.

10. Electrochemical device according to the preceding claim, comprising in addition to the global bypass electrical circuit (8), referred to as "stop", a secondary global bypass electrical circuit (14), referred to as "start", in a simple loop and in the open position, the global start bypass circuit being mounted in parallel with the global stop bypass circuit and comprising a global start bypass module electrically connected to the terminals of the fuel cell and comprising a global start bypass load.

11. Electrochemical device according to the preceding claim, the overall start bypass load and the overall stop bypass load being resistive loads, the electrical resistance of the overall start bypass load being less than the electrical resistance of the overall stop bypass load. [Fig. 8]

Images