Patent ID: 9401521
Filing Date: 2016-07-26
CPC Classification: B60K,B60L,B60W,H01M,Y02E,Y02T

Claim Text:
1. A method of diagnosing a state of a fuel cell system; comprising: calculating, by a processor, a duty ratio and an average output current, based on real-time driving data for a preset driving period during operation of a fuel cell vehicle; obtaining, by the processor, a reference current value from the calculated duty ratio and the calculated average output current, wherein the reference current value is a current value that is obtained when the duty ratio is 1, based on the calculated average output current; determining, by the processor, the state of the fuel cell system by choosing a state graph corresponding to the obtained reference current value among a plurality of state graphs which vary depending on each reference current value; and adjusting, by the processor, an output of a fuel cell stack according to the state of the fuel cell system, wherein the duty ratio is calculated by calculating a ratio of a current output time during which a current is output from the fuel cell stack with respect to the preset driving time.