Gm Global Technolgoy Operations, Inc.

Jason R Kolodziej

Bruce Jeffrey Clingerman

Manish Sinha

Abdullah Basar Alp

Patrick Frost

John Wheat

William Henry Pettit

Balasubramanian Lakshmanan

John P Salvador

Steven D Burch

David S Mathews

Donald H Keskula

Pinkhas A Rapaport

Sriram Ganapathy

Seth E Lerner

Matthew K Hortop

Derek S Kilmer

Frank Leo

Prem Menon

Brian D Shaffer

Shyam Kocha

Dennis Brown

A fuel cell system that employs an on-line self-tuning algorithm that provides temperature control of a fuel cell stack in response to disturbances on the system. The system includes a thermal sub-system having a cooling fluid pump that pumps a cooling fluid through the fuel cell stack, a temperature sensor that measures the temperature of the cooling fluid out of the stack, a radiator that cooling the cooling fluid from the fuel cell stack and a by-pass valve that selectively controls how much of the cooling fluid flows through the radiator or by-passes the radiator. A controller controls the position of the by-pass valve in response to a temperature signal from the temperature sensor. The controller calculates a plurality of variables and a dead-time value, and determines whether the dead-time value should be increased, decreased or kept the same based on an estimate of a dead-time plant model.

Self-tuning thermal control of an automotive fuel cell propulsion system

A fuel cell system that employs a method for determining the potential that a freeze condition will exist after the system is shut-down based on predetermined input, such as ambient temperature, geographical location, user usage profile, date, weather reports, etc. If the system determines that a freeze condition is probable, then the system initiates a purge shut-down of the fuel cell system where water is purged out of the reactant gas flow channels. If the system determines that a freeze condition is unlikely, then it will initiate a normal shut-down procedure without purging the flow channels. The system will then periodically determine if the conditions have changed, and will initiate the purge if a freeze condition subsequently becomes probable.

Fuel cell system water management strategy for freeze capability

A system and method for preventing low performing cells in a fuel cell stack. The method includes periodically providing a pulse of the cathode input airflow at low stack current densities, and comparing the current density output of each cell in response to the pulse. Those cells that do not have significant water accumulation will provide one voltage signature and those cells that do have a significant water accumulation will provide another voltage signature. If one or more of the cells exhibit the voltage signature for water accumulation, then the cathode inlet airflow pulses can be provided more often to prevent the cells from failing.

Detection of cell-to-cell variability in water holdup using pattern recognition techniques

An algorithm for determining a polarization curve of a fuel cell stack. When the fuel cell stack is running and certain data validity criteria have been met, the algorithm goes into a data collection mode where it collects stack data, such as stack current density, average cell voltage and minimum cell voltage. When the stack is shut down, the algorithm uses a cell voltage model to solve a least squares problem to estimate predetermined parameters that define the polarization curve. If the estimated parameters satisfy certain termination criteria, then the estimated parameters are stored to be used by a system controller to calculate the polarization curve of the stack.

Algorithm for online adaptive polarization curve estimation of a fuel cell stack

A method and apparatus for thermal control of air flow in a fuel cell system, capable of accurately controlling the temperature of the air stream entering the water vapor transfer unit, maintaining a desired temperature set-point, and minimizing the time required for the air stream to reach the optimum operating temperature.

Thermal control of cathode inlet air flow for a fuel cell system

A fuel cell system is provided, including an HFR measurement device in electrical communication with a fuel cell stack. The HFR measurement is used online to measure an HFR of the fuel cell stack suitable for calculation of a d(HFR)/d(RH) ratio. A humidity regulator is provided in fluid communication with the fuel cell stack. A controller periodically changes stack operating conditions to perturb an RH of the fuel cell stack, process the HFR response, and compute the d(HFR)/d(RH) ratio. A method for online identification and control of the fuel cell stack humidification is also provided. The d(HFR)/d(RH) ratio is an auxiliary measurement of membrane hydration which is used as a feedback for hydration control.

On-line system identification and control of fuel cell humidification via HFR measurements

A temperature control scheme for a fuel cell stack thermal sub-system in a fuel cell system that uses a non-linear thermal model and disturbance rejection to provide an optimum stack temperature. The thermal sub-system includes a coolant loop directing a cooling fluid through the stack, a pump for pumping the cooling fluid through the coolant loop, and a radiator for cooling the cooling fluid outside of the fuel cell stack. The system includes a controller for controlling the speed of the pump so as to maintain the temperature of the stack at a desired temperature. The controller uses the thermal model to anticipate a temperature of the cooling fluid out of the fuel cell stack to control the speed of the pump.

Nonlinear thermal control of a PEM fuel cell stack

A fuel cell stack antifreeze system that purges a plurality of fuel cell stacks connected in parallel includes a compressor that supplies pressurized cathode gas to each of the plurality of fuel cell stacks. A controller deactivates a first group of one or more of the plurality of fuel cell stacks and maintains operation of a second group of one or more of the plurality of fuel cell stacks. The second group powers the compressor and the compressor purges excess fluid from the first group using the pressurized cathode gas.

Parallel stack antifreeze system

A temperature control system and method for a fuel cell stack cooling system is disclosed. The temperature control system includes a coolant circulation line for circulating a coolant to and from a fuel cell stack. A coolant pump is provided in the coolant circulation line, and a pump &#x394;P sensor is provided in fluid communication with the coolant circulation line on inlet and outlet sides of the coolant pump. The pump &#x394;P sensor measures a change in pump pressure between the inlet and outlet sides of the coolant pump. A pump map is provided having correlated values of pump speed, change in pump pressure and coolant flow rate for correlating the coolant flow rate with the pump speed and the change in pump pressure to attain a desired coolant flow rate for optimum fuel stack cooling.

Fuel cell stack temperature control system and method

A method and apparatus of operating a compressor of a fuel cell system includes modeling a flow meter that measures a mass flow from a compressor with a first mathematical formula and generating a measured signal from the flow meter. The first mathematical formula and the measured signal are processed through a recursive Kalman filter based signal processing algorithm to provide a future signal estimate. The compressor is operated based on the future signal estimate.

Recursive Kalman filter for feedback flow control in PEM fuel cell

Pressure control in a fuel cell is achieved by using an H-infinity controller coupled in a feedback loop between a reactant feed gas valve and a pressure sensor on gas flows to the membrane electrode assembly of the fuel cell. To maintain pressure balance across the membrane, the pressure of the oxidant reactant is used to regulate fuel reactant flow. An integrator windup compensator manages integral windup in the H-infinity control scheme. Control weight, sensor noise weight, and performance weight matrices are incorporated into the H-infinity control model. Respective to PID control, the H-infinity model provides superior performance in the presence of high frequency feedback noise enabling use of low cost control components in the fuel cell and a minimum of EMI shielding.

Growing community of inventors

West Henrietta, NY, United States of America

Jason R Kolodziej