Patent ID: 6635374
Filing Date: 2003-10-21
Classification: B60L,H01M,Y02E,Y02T

Abstract:
A water supply system for a fuel cell, comprising:a water supply valve responsible for a supply quantity of water to be injected from a water tank into an air intake path; a compressor compressing air taken from the air intake path after the water injection; a cooler cooling compressed air delivered from the compressor to supply cooled air to the fuel cell; a set of detectors detecting a flow rate, a pressure and a temperature of the compressed air to be supplied to the fuel cell; a water quantity calculator calculating a necessary water quantity for the fuel cell based on detected flow rate, pressure and temperature of the compressed air to be supplied to the fuel cell, wherein if the detected pressure and temperature of the compressed air increases, then the calculated water quantity necessary for the fuel cell increases, and wherein the water quantity calculator comprises: (a) a calculator calculating an ideally demanded relative humidity for the fuel cell, based on the detected pressure and temperature of the compressed air; and (b) a calculator calculating an ideally demanded quantity of water, based on the detected flow rate of the compressed air and the demanded relative humidity, and a water quantity controller controlling the water supply valve to supply the necessary water quantity.