FUEL CELL CONTROL PROGRAM AND FUEL CELL SYSTEM

Based on an operation condition φ(t) of a polymer electrolyte fuel cell at a time t, the concentration distribution of a radical generation ion and the concentration distribution of a radical scavenging ion in an electrolyte membrane are estimated. Next, a load command p(t+Δt) at a time (t+Δt) is acquired. Next, a reference operation condition φref(t+Δt) under which the load command p(t+Δt) can be realized is acquired. Next, whether or not a judgment index exceeds a first threshold value ϵ1 is judged. When the judgment index exceeds ϵ1, an operation condition which is different from φref(t+≢t) and gives the judgment index of ϵ1 or less is selected as φ(t+Δt). On the other hand, when the judgment index does not exceed ϵ1, φref(t+Δt) is selected as φ(t+Δt). The fuel cell system has a control device for performing such treatments.