Abstract: A fault diagnostic apparatus for a fuel cell electric vehicle and a method therefor are provided. The apparatus includes: a main relay connected to a fuel cell stack; a power converter connected to the main relay; a heater relay connected to the fuel cell stack and the main relay at one end and connected to a cathode oxygen depletion (COD) heater at the other end; and a fuel cell control unit (FCU) connected with the main relay, the power converter, and the heater relay. The FCU diagnoses a fault of the main relay based on an amount of change in stack voltage according to control to turn off and on the heater relay and a power of the power converter according to variable control of a voltage of the power converter, when the vehicle enters a shutdown sequence, and outputs the diagnosed result.

Abstract: An exemplary embodiment of the present disclosure provides an insulation resistance detection apparatus including a processor configured to separate a fuel cell from a high voltage battery depending on an insulation resistance value of a vehicle during driving of the vehicle, and then to measure an insulation resistance value of the fuel cell to determine whether it is a failure of the fuel cell or a failure of the high voltage battery, and when it is the failure of the fuel cell, to determine a cause of the failure by calculating an insulation resistance variation; and a storage configured to store data and algorithms driven by the processor.

Abstract: A fault diagnostic apparatus for a fuel cell electric vehicle and a method therefor are provided. The apparatus includes: a main relay connected to a fuel cell stack; a power converter connected to the main relay; a heater relay connected to the fuel cell stack and the main relay at one end and connected to a cathode oxygen depletion (COD) heater at the other end; and a fuel cell control unit (FCU) connected with the main relay, the power converter, and the heater relay. The FCU diagnoses a fault of the main relay based on an amount of change in stack voltage according to control to turn off and on the heater relay and a power of the power converter according to variable control of a voltage of the power converter, when the vehicle enters a shutdown sequence, and outputs the diagnosed result.

Abstract: The present disclosure relates to an apparatus and method for diagnosing a failure in a fuel cell system. To prevent degradation of a fuel cell stack due to abnormal supply of hydrogen, the apparatus includes a first pressure sensor that measures pressure of hydrogen supplied into the fuel cell stack, a second pressure sensor that measures the pressure of the hydrogen supplied into the fuel cell stack, and a controller that first diagnoses a supply state of the hydrogen based on a first pressure value measured by the first pressure sensor and a second pressure value measured by the second pressure sensor, and further diagnoses the supply state of the hydrogen based on an absolute value of a difference between the first pressure value and the second pressure value.

Abstract: The present invention provides a water trap device for a fuel cell vehicle, in which an anode outlet line is formed to penetrate the inside of a upper portion of a water trap and a coolant discharge pipe having a smaller diameter and extending toward the bottom of the water trap is integrally formed, such that residual coolant collected in the water trap is discharged through a coolant discharge pipe to a water trap outlet valve when residual hydrogen in the anode outlet line is discharged to the water trap outlet valve by the Bernoulli principle.

Abstract: The present invention provides a water trap device for a fuel cell vehicle, in which an anode outlet line is formed to penetrate the inside of a upper portion of a water trap and a coolant discharge pipe having a smaller diameter and extending toward the bottom of the water trap is integrally formed, such that residual coolant collected in the water trap is discharged through a coolant discharge pipe to a water trap outlet valve when residual hydrogen in the anode outlet line is discharged to the water trap outlet valve by the Bernoulli principle.