Abstract: A fuel cell control method and are provided. The method includes collecting state data of a fuel cell stack and then estimating an effective catalytic amount of the fuel cell stack based on the collected state data. A fuel cell system is operated based on the estimated effective catalytic amount to thus optimize the efficiency of the system.

Abstract: A motor control method that includes: calculating an ideal position of a motor rotor based on a Hall sensor signal; calculating a current position of the motor rotor based on a rotation speed of the motor rotor; and calculating a Hall sensor offset angle as the difference between the ideal position of the motor rotor and the current position of the motor rotor.

Abstract: A hydrogen concentration estimating method for a fuel cell includes: measuring a flow rate of air supplied to a fuel cell stack, and comparing the measured flow rate of the air with a predetermined flow rate; determining a model of an air processing system according to a comparison result; and estimating hydrogen concentration of a fuel processing system based on the determined model of the air processing system.

Abstract: A method of calculating a motor position uses a hall sensor. The method can include determining a motor position in response to a signal change of a hall sensor installed to a motor, calculating a basic compensation value for compensating a motor position error due to signal measurement delay of the hall sensor, determining whether a current command condition for a constant-speed operation of the motor is satisfied, calculating a first-up compensation value and a first-down compensation value, calculating an average values of the deviation between d-q axes current commands, and correcting the motor position using the basic compensation value when a difference between the average values is less than a reference average value.

Abstract: A method for controlling a fuel cell vehicle includes acquiring a state data, deriving a mathematical voltage model by substituting the acquired state data into a voltage calculation formula, measuring a voltage of a fuel cell, approximating a mathematical voltage model to a measurement voltage and deriving the reaction area data when the mathematical voltage model approximates the measurement voltage, and controlling the system of the fuel cell vehicle based on the derived reaction area data to eliminate or prevent an over-humidification situation of the fuel cell.

Abstract: A system and method for controlling hydrogen purging of a fuel cell are provided. The method includes calculating a hydrogen supply amount and estimating a hydrogen consumption amount. An estimated hydrogen concentration is then corrected when a difference between the calculated hydrogen supply amount and the estimated hydrogen use amount is greater than a predetermined threshold value.

Abstract: A system and method for diagnosing a fuel cell stack are provided. The method includes determining, by a controller, a time at which diagnosing the fuel cell stack is required based on a plurality of factors and driving a motor adjusted to a first efficiency value for a predetermined first reference time period based on the diagnosis determination. In addition, the controller is configured to drive the motor adjusted to a second efficiency value when the first reference time period has elapsed. A state of the fuel cell stack is then diagnosed based on a voltage variance of the fuel cell stack between driving the motor adjusted to the first efficiency value and second efficiency value.

Abstract: A method for controlling a fuel cell vehicle includes acquiring a state data, deriving a mathematical voltage model by substituting the acquired state data into a voltage calculation formula, measuring a voltage of a fuel cell, approximating a mathematical voltage model to a measurement voltage and deriving the reaction area data when the mathematical voltage model approximates the measurement voltage, and controlling the system of the fuel cell vehicle based on the derived reaction area data to eliminate or prevent an over-humidification situation of the fuel cell.

Abstract: A voltage synchronization method and system are provided. The system includes a main controller that is configured to determine whether voltage synchronization is possible. When the voltage synchronization is determined to be possible, the main controller is configured to transmit a voltage synchronization command to a plurality of auxiliary controllers. The plurality of auxiliary controllers are configured to adjust sensed voltages based on an output voltage of a fuel cell stack when the transmitted voltage synchronization command is received.

Abstract: A fuel cell system and a method for controlling the same are provided. The method includes rapidly increasing an angular speed of a rotating magnetic field of an induction motor to maximize iron loss of the induction motor, thereby resulting in an increase in the temperature of a rise cell stack. The method further includes eliminating torque of a driving motor generated by an increase in the angular speed of the rotating magnetic field, using a torque eliminator. The torque eliminator includes a P-stage reducer or a hydraulic break.

Abstract: A device and a method for controlling a cold start of a fuel cell system are provided and are capable of increasing a fuel cell load to reduce a cold start time using a kinetic energy storage method for a rotor of a motor for driving a fuel cell system. The method improves cold start performance by performing self-heating of a fuel cell stack based on an increase in an output current amount of a fuel cell and by restricting a motor torque simultaneously with generating the motor torque while applying a current to a motor when a vehicle stops to consume an output current of the fuel cell.

Abstract: A method and system for computing a motor speed and a rotor position using a hall sensor are provided. The method improves precision for computing the speed of the motor rotating at a high speed and the rotor position using the hall sensor based on configurations, such as the hall sensor mounted in the motor as a position sensor, a motor controller configured to receive a signal of the hall sensor to operate the motor, and a microcomputer configured to store a time when the motor controller senses the timing of a change in the signal of the hall sensor.

Abstract: A failure determination method for a motor system includes setting a current value required to initially drive a motor to a first current command value, increasing a rotational speed of a rotating magnetic field of the motor up to a preset reference speed, comparing an intensity of a back electromotive force, generated when a rotor of the motor is rotated at the preset reference speed, to a magnitude of a voltage applied to apply current in accordance with the set first current command value, and determining a cause of a failure of the motor based on the comparison.

Abstract: A system and method for a cold start of a vehicle are provided. The method includes setting a target electrical angle by adding a setting angle to a previously stored initial electrical angle of a driving motor and applying an electric current value that corresponds to the set target electrical angle to the driving motor.

Abstract: A system and method for diagnosing a fuel cell stack are provided. The method includes determining, by a controller, a time at which diagnosing the fuel cell stack is required based on a plurality of factors and driving a motor adjusted to a first efficiency value for a predetermined first reference time period based on the diagnosis determination. In addition, the controller is configured to drive the motor adjusted to a second efficiency value when the first reference time period has elapsed. A state of the fuel cell stack is then diagnosed based on a voltage variance of the fuel cell stack between driving the motor adjusted to the first efficiency value and second efficiency value.

Abstract: A method and system for computing a motor speed and a rotor position using a hall sensor are provided. The method improves precision for computing the speed of the motor rotating at a high speed and the rotor position using the hall sensor based on configurations, such as the hall sensor mounted in the motor as a position sensor, a motor controller configured to receive a signal of the hall sensor to operate the motor, and a microcomputer configured to store a time when the motor controller senses the timing of a change in the signal of the hall sensor.

Abstract: A device and a method for controlling a cold start of a fuel cell system are provided and are capable of increasing a fuel cell load to reduce a cold start time using a kinetic energy storage method for a rotor of a motor for driving a fuel cell system. The method improves cold start performance by performing self-heating of a fuel cell stack based on an increase in an output current amount of a fuel cell and by restricting a motor torque simultaneously with generating the motor torque while applying a current to a motor when a vehicle stops to consume an output current of the fuel cell.

Abstract: A system and method for a cold start of a vehicle are provided. The method includes setting a target electrical angle by adding a setting angle to a previously stored initial electrical angle of a driving motor and applying an electric current value that corresponds to the set target electrical angle to the driving motor.

Abstract: A failure determination method for a motor system includes setting a current value required to initially drive a motor to a first current command value, increasing a rotational speed of a rotating magnetic field of the motor up to a preset reference speed, comparing an intensity of a back electromotive force, generated when a rotor of the motor is rotated at the preset reference speed, to a magnitude of a voltage applied to apply current in accordance with the set first current command value, and determining a cause of a failure of the motor based on the comparison.

Abstract: A fuel cell system and a method tor controlling the same are provided. The method includes rapidly increasing an angular speed of a rotating magnetic field of an induction motor to maximize iron loss of the induction motor, thereby resulting in an increase in the temperature of a rise cell stack. The method further includes eliminating torque of a driving motor generated by an increase in the angular speed of the rotating magnetic field, using a torque eliminator. The torque eliminator includes a P-stage reducer or a hydraulic break.