| 摘要 |
PURPOSE:To prevent a drop in cell performance due to an increase in electrical resistance in relation to a shortage in the number of 3-phase interfaces of a catalyst layer due to insufficient catalyst phosphoric acid, and the reduction of phosphoric acid in a phosphoric acid matrix by controlling the pressure lowering operation of an exhaust gas system and preventing the evaporation of an electrolyte over a saturation region. CONSTITUTION:When a temperature rise precedes a pressure rise, an ambient condition for an electrolyte 8 exceeds a saturation region and there appears a problem of evaporation. A cell cooling water temperature control system detects an exhaust gas pressure 14 and an approximate saturation temperature value is obtained with a pressure function generator 34. This saturation temperature value and a cooling water temperature set value 26 are compared with each other in a low value selector 31. And a low value is thereby selected and adopted as a set value for a cell cooling water temperature control value. When a pressure drop precedes a temperature drop at the time of lowering pressure, an exhaust gas discharge pressure control system detects a typical cell temperature 6 and an approximate saturation pressure value is obtained with a temperature function generator 30. And this saturation pressure value and an exhaust gas pressure set value 25 are compared with each other in a high value selector 27. And a high value is selected and used as a set value for an exhaust gas discharge pressure control value. |
