Abstract: A fuel cell system employing a floating base load hybrid strategy for reducing fast voltage transients of a FCPM. A power request signal is applied to an average power calculation processor that calculates the average power requested over a predetermined previous period of time. A weighting function processor provides a weighting function based on the state of charge of an EESS. The power available from the FCPM and the EESS is applied to a power comparison processor. The available power is compared to the power request to provide a difference value between what is currently being provided and what is desired. The difference value is compared to power limit values of the EESS. The output value of this comparison is added to a filtered value to generate a signal for the change in the output power of the fuel cell stack based on the power request.

Abstract: A system for controlling the power output of a fuel cell stack and a battery in a hybrid fuel cell system. The system includes a power damping filter that receives a power request signal, and damps the request to reduce large changes in the power request. A battery state of charge controller receives the difference between a battery state of charge set-point and the actual battery state of charge, and provides a battery power signal that attempts to maintain the battery state of charge at the set-point. The damped power signal and the battery power signal are added to generate a system power demand signal that satisfies the driver power request using the battery power and fuel cell stack power, and uses the fuel cell stack power to charge the battery during low power transients or if the battery state of charge is below the set-point.

Abstract: A method of controlling the ventilation system for an energy source in a fuel cell vehicle is disclosed, which includes an HVAC system, a fluid reserve, and a rechargeable energy storage system (RESS), capable of controlling a temperature of the RESS to militate against damage to or a shortened life of the battery, while maximizing vehicle durability, efficiency, performance, and passenger comfort.

Abstract: A propulsion system for a fuel cell hybrid vehicle that includes a fuel cell system and an EESS, where the propulsion system employs an algorithm for increasing system efficiency. A power limit value is defined as the maximum system efficiency times the charge/discharge efficiency of the EESS. If the vehicle operator requests a power greater than the power limit value, then the fuel cell system will preferably provide the power, and if the power request from the vehicle operator is less than the power limit value, then the EESS will preferably provide the power. The algorithm also considers changing operation conditions and parameters that impact the fuel cell system efficiency and the electric energy storage system efficiency, such as the state of charge of the EESS and regenerative braking.

Abstract: A multi-stage compressor system that compresses air supplied to a cathode of a fuel cell system includes a first stage compressor that compresses inlet air to provide a first pressurized air stream at a first pressure. A second stage compressor includes a compression unit that compresses the first pressurized air stream to a second pressurized air stream at a second pressure. A drive unit drives the compression unit using expansion energy of an exhaust stream of the fuel cell. A first heat exchanger enables heat transfer between the second pressurized air stream and the exhaust stream to heat the exhaust stream.

Abstract: A system and method for reducing RH cycling of the membranes in a fuel cell stack. A control algorithm damps a power request signal using a first order filter during low power transients so that the fuel cell stack continues generating power at a higher rate than is requested. The excess power generated by the stack is used to recharge a battery in the fuel cell system. The damped power signal is weighted so that more fuel cell stack power is provided for a low battery state of charge unless stack power is provided for a high battery state of charge.

Abstract: A system for controlling the power output of a fuel cell stack and a battery in a hybrid fuel cell system. The system includes a power damping filter that receives a power request signal, and damps the request to reduce large changes in the power request. A battery state of charge controller receives the difference between a battery state of charge set-point and the actual battery state of charge, and provides a battery power signal that attempts to maintain the battery state of charge at the set-point. The damped power signal and the battery power signal are added to generate a system power demand signal that satisfies the driver power request using the battery power and fuel cell stack power, and uses the fuel cell stack power to charge the battery during low power transients or if the battery state of charge is below the set-point.

Abstract: A fuel cell system employing a floating base load hybrid strategy for reducing fast voltage transients of a FCPM. A power request signal is applied to an average power calculation processor that calculates the average power requested over a predetermined previous period of time. A weighting function processor provides a weighting function based on the state of charge of an EESS. The power available from the FCPM and the EESS is applied to a power comparison processor. The available power is compared to the power request to provide a difference value between what is currently being provided and what is desired. The difference value is compared to power limit values of the EESS. The output value of this comparison is added to a filtered value to generate a signal for the change in the output power of the fuel cell stack based on the power request.

Abstract: A method for constant-current generation by means of a rotational energy source, a generator and a control circuit connected to the generator. Mechanical rotational energy is generated by the energy source and the mechanical rotational energy is transmitted to the generator rotor. The magnetic field distribution produced in the generator is controlled by the control circuit that controls the current distribution in the generator between load current and generator current by feedback control by generating an opposing magnetic field. The power uptake and the current output are adapted without losses and the alternating current generated by the generator is transferred to an averaging direct-current circuit. A suitable device for carrying out the method is also provided.

Abstract: A fuel cell assembly having a flow distribution subassembly that comprises four sets of flow channels, the first set facing an anode for distribution of a fuel reactant to said anode, the second set facing a cathode for distribution of an oxidant to said cathode, the third set in flow communication with said second set and in heat transfer relation with at least one of said anode and said cathode, and the fourth set receiving a coolant different from said oxidant.

Abstract: A multi-stage compressor system that compresses air supplied to a cathode of a fuel cell system includes a first stage compressor that compresses inlet air to provide a first pressurized air stream at a first pressure. A second stage compressor includes a compression unit that compresses the first pressurized air stream to a second pressurized air stream at a second pressure. A drive unit drives the compression unit using expansion energy of an exhaust stream of the fuel cell. A first heat exchanger enables heat transfer between the second pressurized air stream and the exhaust stream to heat the exhaust stream.

Abstract: The invention relates to a method for constant-current generation by means of a rotational energy source, a generator and a control circuit connected to the generator. Mechanical rotational energy is generated by the energy source and the mechanical rotational energy is transmitted to the generator rotor. The magnetic field distribution produced in the generator is controlled by the control circuit that controls the current distribution in the generator between load current and generator current by feedback control by generating an opposing magnetic field. The power uptake and the current output are adapted without losses and the alternating current generated by the generator is transferred to an averaging direct-current circuit. The invention further relates to a suitable device for carrying out the inventive method.

Abstract: The present invention discloses an electromechanically operable disc brake for automotive vehicles which comprises a floating caliper as well as an actuating unit arranged on the caliper. The actuating unit includes an electric motor which, by the intermediary of a reduction gear, readjusts an actuating element which is used to move one of two friction linings that are slidable in the brake caliper into engagement with a brake disc. To permit an individual adjustment of the desired brake force, especially for use of the disc brake in an automotive vehicle, according to the present invention, a force-measuring device (23) is interposed in the flux of force between the caliper (1) and the actuating unit (2), and the output signals of device (23) are adapted to be sent to a control circuit (26) that influences the current supplied to the electric motor (6), and/or the voltage.