| 摘要 |
PROBLEM TO BE SOLVED: To save energy by changing a compressor discharge pressure in accordance with a load of an on-vehicle fuel cell and compressing the required amount of air of the fuel cell to reduce power loss. SOLUTION: An compressor for air supply of the fuel cell 15 is composed of two steps, namely, a low pressure step 2 and a high pressure step 3. Each step is mutually connected by a motor 1 and clutches 6, 7. Furthermore, a discharge pipe 10 of the low pressure step compressor 2 is provided with a selector valve 13, and a pipe 20 for supplying low pressure step discharge air into the fuel cell 15 as it is and pipes 21, 11 for supplying discharge air through the high pressure step compressor 3 are provided. When a load is low, compressor driving power is reduced by the supply of low pressure step air to obtain energy saving effect. Moreover, the motor 1 is driven by changing its speed by inverter control to control the number of revolutions of the compressor in order to obtain further energy saving effect. Furthermore, the operation is possible at a pressure ratio at which a temperature of discharge air becomes a fuel cell operation temperature, and it is unnecessary to cool discharge air. |
