Abstract: A system and method for detecting an anode pressure sensor failure in a fuel cell system. The system and method include a controller that sets an initial minimum anode pressure sensor value and an initial maximum anode pressure sensor value. The controller determines a desired time interval for sampling anode pressure measurements and determines a total number of samples of anode pressure measurements to be collected by the controller from an anode pressure sensor. The controller also compares a pressure difference between the initial or a measured minimum anode pressure and the initial or a measured maximum anode pressure to a predetermined pressure difference threshold and sets a pressure sensor fault if the pressure difference between the initial or measured minimum anode pressure and the initial or maximum anode pressure is less than the predetermined pressure difference threshold.

Abstract: An apparatus and method to determine the relative humidity of a fuel cell system. A controller is cooperative with a first device and a second device to receive a valve signal and a high frequency resistance value. The controller controls the relative humidity of a fuel cell stack based on the estimation of the relative humidity of the fuel cell stack based on one or more algorithms. The controller modifies the relative humidity of the fuel cell stack through changes in the position of a valve based on at least one of the valve signal and the high frequency resistance value. In one form, the relative humidity of the fuel cell system is determined without the need of a humidity sensor.

Abstract: A method for determining membrane humidification by determining the membrane protonic resistance of a fuel cell stack at humidified conditions, and normalizing the base resistance of the fuel cell stack against the base resistance of a reference fuel cell stack.

Abstract: A system and method for determining whether there is a cross-over leak, or other failure, in a WVT unit that humidifies the cathode inlet airflow to a fuel cell stack in a fuel cell system. The fuel cell system includes an HFR circuit that determines the humidity level of the membranes in the fuel cell stack and an RH sensor that measures the relative humidity of the airflow to the cathode side of the fuel cell stack. The HFR humidity calculation is compared to RH measurements from the RH sensor, and if the difference between the two RH values is greater than a predetermined calibration value, then the system may determine that the WVT unit is failing and needs to be serviced or replaced.

Abstract: A system and method for detecting an anode pressure sensor failure in a fuel cell system. The system and method include a controller that sets an initial minimum anode pressure sensor value and an initial maximum anode pressure sensor value. The controller determines a desired time interval for sampling anode pressure measurements and determines a total number of samples of anode pressure measurements to be collected by the controller from an anode pressure sensor. The controller also compares a pressure difference between the initial or a measured minimum anode pressure and the initial or a measured maximum anode pressure to a predetermined pressure difference threshold and sets a pressure sensor fault if the pressure difference between the initial or measured minimum anode pressure and the initial or maximum anode pressure is less than the predetermined pressure difference threshold.

Abstract: The present invention provides a universal single switch driving system for power wheelchairs, which can be attached to any wheelchair joystick and remotely controlled, by any single switch available for persons with disabilities.

Abstract: A system and method for determining whether there is a cross-over leak, or other failure, in a WVT unit that humidifies the cathode inlet airflow to a fuel cell stack in a fuel cell system. The fuel cell system includes an HFR circuit that determines the humidity level of the membranes in the fuel cell stack and an RH sensor that measures the relative humidity of the airflow to the cathode side of the fuel cell stack. The HFR humidity calculation is compared to RH measurements from the RH sensor, and if the difference between the two RH values is greater than a predetermined calibration value, then the system may determine that the WVT unit is failing and needs to be serviced or replaced.

Abstract: A method for determining if more hydrogen has been added to a fuel cell system than a predetermined threshold amount to detect leaks in an anode subsystem or a cathode subsystem of a fuel cell system. The method includes determining a quantity of hydrogen added to the fuel cell system for a given period of time during a predetermined operating condition of the fuel cell system and determining whether the quantity of hydrogen added is more than the predetermined threshold amount. The method also includes adapting an anode subsystem reactant gas concentration model if the quantity of hydrogen added to the fuel cell system is more than the predetermined threshold amount to provide precise control of pressure in the anode subsystem and the cathode subsystem of the fuel cell system.

Abstract: An electronic engine controller is configured to execute a process of adapting a base value of the volumetric efficiency of an engine through the addition of a correction value of the volumetric efficiency. The process includes comparing an estimated mass air flow value calculated using a speed-density equation, with an actual mass air flow value measured by a mass air flow (MAF) sensor. A percentage error of the estimated mass air flow value as compared to the actual mass air flow value is calculated. When the percentage error indicates that the air flow is at steady state, then the process updates the VE correction value, by integrating the percentage error. The new correction value, thus computed, is then stored in a cell of an array corresponding to the current engine operating condition. The process is configured to add the correction value to the corresponding base value to produce an updated value of the VE, valid for that operating condition.