Honda Motor Co., Ltd.
Water electrolysis system and control method therefor

Abstract:

A water electrolysis system produces hydrogen gas at a higher pressure than oxygen gas. A Peltier cooler is disposed between a gas-liquid separator and a back pressure valve in a hydrogen gas flow path, and cools and dehumidifies the hydrogen gas. A temperature sensor measures a temperature in the vicinity of the Peltier cooler, and outputs a temperature measurement value. A pressure sensor measures a pressure of the hydrogen gas between a cathode and the back pressure valve in the hydrogen gas flow path, and outputs a pressure measurement value. A control unit controls a cooling temperature by the Peltier cooler, in a manner so that the temperature measurement value becomes a target temperature that exceeds the freezing point of water corresponding to the pressure measurement value. At least a portion of the target temperature becomes lower as the pressure measurement value increases.