Abstract: A computer-implemented method when executed by data processing hardware causes the data processing hardware to perform operations. The operations include estimating, via an adaptive algorithm, a balance of plant (BoP) power loss of a BoP of a fuel cell system (FCS), receiving, at the adaptive algorithm, an application power request, and executing, via the adaptive algorithm, a BoP degradation computation. The operations also include learning, via a plurality of sensors, a BoP loss error in the estimated BoP power loss based on a comparison with the BoP degradation computation, applying, based on the learned BoP loss error, an adaptation factor to the BoP degradation computation, and generating, via the adaptive algorithm, a stack power request based on the application power request and the estimated BoP power loss.

Abstract: A control system for a vehicle includes data processing hardware and memory hardware in communication with the data processing hardware. The memory hardware stores instructions that when executed on the data processing hardware cause the data processing hardware to perform operations. The operations include receiving, at a propulsion controller, power generation, comparing, via the propulsion controller, battery data with a state of charge threshold, and executing, based on the comparison of the battery data, a power sink protocol including at least one mode control via a fuel cell system. The operations also include generating, based on the at least one mode control, at least one of a compressor command and a valve command via an airflow system and regulating, via the at least one generated compressor command and the valve command, an airflow of the airflow system.

Abstract: A pre-charge system for a DC electric power system includes a high-voltage electric power bus that electrically connects to an external bus. A contactor includes a first switch arranged to control electric power through the positive bus link, and a second switch arranged to control electric power through the negative bus link. A pre-charge resistor is arranged in parallel with the first switch. A controller is operatively connected to the first and second switches, and in communication with a voltage sensor. The controller includes an instruction set to activate the second switch, periodically monitor the electrical potential, determine a time-rate of change in the electrical potential, and close the first switch when the time-rate of change in the electrical potential is less than a first threshold.

Abstract: A system includes a conversion device of a charging station, the conversion device connected to a first energy source of the charging station, and a controller configured to perform an impedance measurement applied to an energy storage system, the energy storage system selected from at least one of a second energy source of the charging station and a battery system of a vehicle. The controller is configured to cause the first energy source to generate a first excitation signal for measuring a first energy source impedance, control the conversion device to adjust a parameter of the first excitation signal to convert the first excitation signal to a converted excitation signal, apply the converted excitation signal to the energy storage system, detect a current response of the energy storage system, and estimate the impedance of the energy storage system based on the current response.

Abstract: A pre-charge system for a DC electric power system includes a high-voltage electric power bus that electrically connects to an external bus. A contactor includes a first switch arranged to control electric power through the positive bus link, and a second switch arranged to control electric power through the negative bus link. A pre-charge resistor is arranged in parallel with the first switch. A controller is operatively connected to the first and second switches, and in communication with a voltage sensor. The controller includes an instruction set to activate the second switch, periodically monitor the electrical potential, determine a time-rate of change in the electrical potential, and close the first switch when the time-rate of change in the electrical potential is less than a first threshold.

Abstract: A system for transferring DC electric power to a DC electric power system includes an electric power source, a DC-DC power converter, a system power bus including a capacitor, a first current sensor, a second current sensor, a third current sensor, and a controller. The DC-DC power converter includes a switched inductance circuit including an inductor, a high-voltage switch, and a diode. The second current sensor monitors a second current in the system power bus between the DC-DC power converter and the capacitor. The controller determines a parametric setpoint for the system power bus, determines the first current, the second current, and the third current in the system power bus, and controls the switching DC-DC power converter based upon the parametric setpoint, the first current, the second current, and the third current.

Abstract: A method for evaluating voltage sensor output using a diagnostic system includes: measuring an overall fuel cell stack voltage using a stack voltage sensor; identifying a fuel cell voltage of a first end cell using a first end cell voltage sensor and a second end cell using a second end cell voltage sensor; determining if a maximum value of the overall fuel cell stack voltage, the fuel cell voltage of the first end cell or the second end cell is less than a sensor limit, and if a minimum value of the fuel cell voltages is greater than the sensor limit; performing a test to identify if the maximum value is greater than an average sensor signal value and if the average sensor signal value is greater than the minimum value; and conducting a test to identify if the minimum value is less than a first predetermined threshold.

Abstract: A fuel cell charging system includes a fuel cell stack having a first operating direct current (DC) voltage between fuel check stack terminals, a high voltage system operating at a first DC operating voltage different than and generally higher than the first operating voltage of the fuel cell stack, a boost converter in electrical connection with the fuel cell stack and the high voltage system, and a stack charging component that applies a second DC operating voltage, generally of lower value than that of the first normal operating voltage, to the fuel cell stack. The boost converter transfer electrical power from the fuel cell stack to the high voltage system during fuel cell operation. Characteristically, the second DC operating voltage applied to the fuel cell stack terminals is typically lower in value than that of the first DC operating voltage of both the fuel cell stack and the HV electrical system and is stepped down from the first DC operating voltage of the HV electrical system.

Abstract: A method for evaluating voltage sensor output using a diagnostic system includes: measuring an overall fuel cell stack voltage using a stack voltage sensor; identifying a fuel cell voltage of a first end cell using a first end cell voltage sensor and a second end cell using a second end cell voltage sensor; determining if a maximum value of the overall fuel cell stack voltage, the fuel cell voltage of the first end cell or the second end cell is less than a sensor limit, and if a minimum value of the fuel cell voltages is greater than the sensor limit; performing a test to identify if the maximum value is greater than an average sensor signal value and if the average sensor signal value is greater than the minimum value; and conducting a test to identify if the minimum value is less than a first predetermined threshold.

Abstract: A fuel cell voltage recovery system includes a fuel cell stack having a fuel cell stack voltage between fuel cell stack terminals which is at a first voltage during normal fuel cell operation. The system also includes a high voltage electrical system operating at a first DC operating voltage that is generally higher than the first voltage of the fuel cell stack. A boost converter in electrical connection with the fuel cell stack and the high voltage electrical system operates in a normal control mode to transfer electrical power from the fuel cell stack to the high voltage electrical system through regulation and control of average stack output current (boost input current) during normal fuel cell operation. The boost converter can also operate in a voltage control mode to lower the fuel cell stack voltage to a second voltage that is lower than the first voltage. A FCS controller controls the operation of the boost converter.

Abstract: A fuel cell voltage recovery system includes a fuel cell stack having a fuel cell stack voltage between fuel cell stack terminals which is at a first voltage during normal fuel cell operation. The system also includes a high voltage electrical system operating at a first DC operating voltage that is generally higher than the first voltage of the fuel cell stack. A boost converter in electrical connection with the fuel cell stack and the high voltage electrical system operates in a normal control mode to transfer electrical power from the fuel cell stack to the high voltage electrical system through regulation and control of average stack output current (boost input current) during normal fuel cell operation. The boost converter can also operate in a voltage control mode to lower the fuel cell stack voltage to a second voltage that is lower than the first voltage. A FCS controller controls the operation of the boost converter.

Abstract: A fuel cell charging system includes a fuel cell stack having a first operating direct current (DC) voltage between fuel check stack terminals, a high voltage system operating at a first DC operating voltage different than and generally higher than the first operating voltage of the fuel cell stack, a boost converter in electrical connection with the fuel cell stack and the high voltage system, and a stack charging component that applies a second DC operating voltage, generally of lower value than that of the first normal operating voltage, to the fuel cell stack. The boost converter transfer electrical power from the fuel cell stack to the high voltage system during fuel cell operation. Characteristically, the second DC operating voltage applied to the fuel cell stack terminals is typically lower in value than that of the first DC operating voltage of both the fuel cell stack and the HV electrical system and is stepped down from the first DC operating voltage of the HV electrical system.

Abstract: Methods and systems for identification of slave elements and/or cells in a communication system within a vehicle. In some implementations, such methods may comprise measuring a first voltage of a first slave device of a plurality of slave devices within the communication system, and measuring a second voltage of a second slave device of the plurality of slave devices within the communication system. A location of at least the first and second slave devices, which may be linked with respective cells, such as battery cells or fuel cells, may then be identified by comparing at least the first voltage with the second voltage.

Abstract: A power converter includes positive and negative input lines and an input capacitor coupled across the input lines. The power converter also includes a switch coupled across the input lines that includes a control contact and an additional contact. The power converter also includes switch controller coupled to the control contact and that includes positive and negative input connections. The power converter also includes a contactor diagnostic supply interface coupled between the positive input connection and the additional contact.

Abstract: Methods and systems for identification of slave elements and/or cells in a communication system within a vehicle. In some implementations, such methods may comprise measuring a first voltage of a first slave device of a plurality of slave devices within the communication system, and measuring a second voltage of a second slave device of the plurality of slave devices within the communication system. A location of at least the first and second slave devices, which may be linked with respective cells, such as battery cells or fuel cells, may then be identified by comparing at least the first voltage with the second voltage.

Abstract: A motorized cart collector for pulling two rows of carts in a forward direction over a surface includes a mobile body having a frame and a cart connector assembly. The cart connector assembly is pivotally connected to a rear end of the frame for pivotal movement about a vertical axis that is approximately perpendicular to the surface. The cart connector assembly includes first and second cart connectors that respectively configured to simultaneously attach to first and second lead carts. Also disclosed is a method of pulling two rows of carts using the cart collector.