Abstract: A controller (500) in an electric drive system is used to determine whether a phase current imbalance in the output winding of a power generator (204) exists. During operation, the controller (500) receives a set of power generator diagnostic values corresponding to the phase currents output by the power generator (204). Next, the controller (500) determines a set of expected operating phase current values. The controller (500) then compares the obtained diagnostic values to one or more corresponding expected operating values. If the difference is greater than a threshold, the controller (500) provides an appropriate fault indication indicative of a phase current imbalance.

Abstract: A machine propelled by an electric motor and subject to a deration scheme is described wherein deration is specified by a combination of a temperature signal indicating a degree to which a machine component is overheating. The machine includes an electronic controller that receives a temperature signal indicative of a current temperature status of the electric motor. The electronic controller receives a motor speed signal indicative of a current speed status of the electric motor. The electronic controller calculates, in accordance with a derating scheme, a deration value for the electric motor, the deration value being determined by applying a set of current operating state parameter values to the derating scheme. The set of current operating state parameters include: a motor speed parameter value; and a temperature parameter value.

Abstract: A method of regulating temperature of a transistor-based component of a power system is disclosed. The method may include operating the power system to supply electric power to the transistor-based component and converting the electric power from direct current to alternating current, or alternating current to direct current, using the transistor-based component, thereby creating heat in the transistor-based component. The method may include outputting the electric power from the transistor-based component and supplying the electric power to an electrically-powered component to perform an output operation.

Abstract: A drive system for a machine having an engine, a generator, a trolley drive arrangement, a motor, wheels and auxiliary devices is provided. The drive system includes an inverter circuit and an auxiliary driver both being operatively connected to the trolley drive arrangement. The inverter circuit may be coupled to each of the generator and the motor. The auxiliary driver may be coupled to each of the generator and the auxiliary devices. The inverter circuit and the auxiliary driver may be configured to automatically communicate power from the trolley drive arrangement and any power from the auxiliary devices to the motor in a trolley propel mode, and automatically communicate power from the motor to the engine, the trolley drive arrangement, and optionally to a hybrid system if applicable, in a dynamic braking mode, while attached to trolley lines so as to eliminate fuel consumption while attached to the trolley lines.

Abstract: A machine propelled by an electric motor and subject to a deration scheme is described wherein deration is specified by a combination of a temperature signal indicating a degree to which a machine component is overheating. The machine includes an electronic controller that receives a temperature signal indicative of a current temperature status of the electric motor. The electronic controller receives a motor speed signal indicative of a current speed status of the electric motor. The electronic controller calculates, in accordance with a derating scheme, a deration value for the electric motor, the deration value being determined by applying a set of current operating state parameter values to the derating scheme. The set of current operating state parameters include: a motor speed parameter value; and a temperature parameter value.

Abstract: An electric drive system includes a fuel-driven prime mover for driving an electrical power alternator controlled at least in part by an excitation voltage is disclosed. The electrical power alternator makes electrical power available on a DC link having a voltage characteristic and a current characteristic. A method for managing the response of the alternator includes determining a voltage of the DC link and a torque command by an operator. The torque command is used to derive a mechanical power that is being commanded. A desired voltage of the DC link is determined based on the derived mechanical power, and an excitation voltage command signal is provided based on the desired voltage of the DC link by use of a closed loop controller. An actual excitation voltage is applied to the electrical power alternator based on the excitation voltage command signal.

Abstract: A drive system for a machine having an engine, a generator, a trolley drive arrangement, a motor, wheels and auxiliary devices is provided. The drive system includes an inverter circuit and an auxiliary driver both being operatively connected to the trolley drive arrangement. The inverter circuit may be coupled to each of the generator and the motor. The auxiliary driver may be coupled to each of the generator and the auxiliary devices. The inverter circuit and the auxiliary driver may be configured to automatically communicate power from the trolley drive arrangement and any power from the auxiliary devices to the motor in a trolley propel mode, and automatically communicate power from the motor to the engine, the trolley drive arrangement, and optionally to a hybrid system if applicable, in a dynamic braking mode, while attached to trolley lines so as to eliminate fuel consumption while attached to the trolley lines.

Abstract: An electric drive system includes a fuel-driven engine (202) driving an electrical power generator (204) that provides power to one or more electric drive motors (210). A method of load management in the electric drive system includes receiving an actual fuel signal, an engine speed (920) signal, a throttle position signal, a motor speed (712) signal, an intake air pressure, a barometric pressure signal, and an intake air temperature signal. These values are used to determine a torque limit. The torque limit is used to limit a torque command to the electric drive motors (210) such that the torque command is consistent with the operating capabilities of the engine (202).

Abstract: A controller (500) in an electric drive system is used to determine the operating condition of array of rotating diodes (302B) within a generator (204). During operation, the controller (500) receives a set of generator inputs, a set of machine parameters, and a set of diagnostic values. Next, the controller (500) determines a set of expected operating values corresponding to the set of diagnostic values. The controller (500) then compares the obtained diagnostic values to one or more corresponding expected operating values. If the difference is greater than a threshold, the controller (500) provides a fault indication that one or more of the array of rotating diodes (302B) has malfunctioned.

Abstract: A cooling system includes a cooling duct extending between a first component and a second component of a machine. A motor powered fan in the cooling duct creates an airflow in the duct. First and second temperature sensors are disposed to measure, respectively, first and second temperatures, which are associated with first and second temperature limits in first and second components. An electronic controller provides a motor command signal, receives the first and second temperatures, calculates first and second temperature differences to generate first and second blower commands based on the respective temperature differences, and calculates a feed-forward blower motor command based on a machine load factor. The electronic controller selects the greater of the first blower command, the second blower command, and the feed-forward blower command to be a maximum command, and determines and provides the motor command signal to the motor based on the maximum command.

Abstract: A method of regulating temperature of a transistor-based component of a power system is disclosed. The method may include operating the power system to supply electric power to the transistor-based component and converting the electric power from direct current to alternating current, or alternating current to direct current, using the transistor-based component, thereby creating heat in the transistor-based component. The method may include outputting the electric power from the transistor-based component and supplying the electric power to an electrically-powered component to perform an output operation.

Abstract: An electric drive system includes a fuel-driven engine (202) driving an electrical power generator (204) that provides power to one or more electric drive motors (210). A method of load management in the electric drive system includes receiving an actual fuel signal, an engine speed (920) signal, a throttle position signal, a motor speed (712) signal, an intake air pressure, a barometric pressure signal, and an intake air temperature signal. These values are used to determine a torque limit. The torque limit is used to limit a torque command to the electric drive motors (210) such that the torque command is consistent with the operating capabilities of the engine (202).

Abstract: A fluid flow method and apparatus are described. The apparatus includes a trough coupled between tanks to provide an air flow down between the tanks.

Abstract: An electric drive system includes a fuel-driven engine (202) driving an electrical power generator (204) that provides power to one or more electric drive motors (210). A method of load management in the electric drive system includes receiving an actual fuel signal, an engine speed (920) signal, a throttle position signal, a motor speed (712) signal, an intake air pressure, a barometric pressure signal, and an intake air temperature signal. These values are used to determine a torque limit. The torque limit is used to limit a torque command to the electric drive motors (210) such that the torque command is consistent with the operating capabilities of the engine (202).

Abstract: An electric drive system includes a fuel-driven prime mover for driving an electrical power alternator controlled at least in part by an excitation voltage is disclosed. The electrical power alternator makes electrical power available on a DC link having a voltage characteristic and a current characteristic. A method for managing the response of the alternator includes determining a voltage of the DC link and a torque command by an operator. The torque command is used to derive a mechanical power that is being commanded. A desired voltage of the DC link is determined based on the derived mechanical power, and an excitation voltage command signal is provided based on the desired voltage of the DC link by use of a closed loop controller. An actual excitation voltage is applied to the electrical power alternator based on the excitation voltage command signal.

Abstract: A system for detecting a short circuit in a direct current (DC) link (312), wherein the DC link (312) is coupled with a rectifier (206) which includes a set of rectifier diode pairs (310). During operation, a controller (500) receives a set of outputs of a power generator 204, a set of machine parameters, and a set of diagnostic values. Next, the controller (500) determines a set of expected operating values corresponding to the set of diagnostic values. The controller (500) then compares diagnostic values to corresponding expected operating values. If the difference between the diagnostic values and the expected operating values exceeds a threshold, the controller (500) provides a flag to indicate that a short circuit condition exists.

Abstract: A controller (500) in an electric drive system is used to develop power generation failure diagnostics. During operation, the controller (500) receives a set of generator inputs, a set of machine parameters, and a set of diagnostic values. Next, the controller (500) determines a set of expected operating values corresponding to the set of diagnostic values. The controller (500) then compares the obtained diagnostic values to one or more corresponding expected operating values. If the difference is greater than a threshold, the controller (500) provides an appropriate fault indication.

Abstract: An electric drive system includes a fuel-driven engine (202) driving an electrical power generator (204) that provides power to one or more electric drive motors (210). A method of load management in the electric drive system includes receiving an actual fuel signal, an engine speed (920) signal, a throttle position signal, a motor speed (712) signal, an intake air pressure, a barometric pressure signal, and an intake air temperature signal. These values are used to determine a torque limit. The torque limit is used to limit a torque command to the electric drive motors (210) such that the torque command is consistent with the operating capabilities of the engine (202).

Abstract: A system for detecting a short circuit in a direct current (DC) link (312), wherein the DC link (312) is coupled with a rectifier (206) which includes a set of rectifier diode pairs (310). During operation, a controller (500) receives a set of inputs from a power generator 204, a set of machine parameters, and a set of diagnostic values. Next, the controller (500) determines a set of expected operating values corresponding to the set of diagnostic values. The controller (500) then compares diagnostic values to corresponding expected operating values. If the difference between the diagnostic values and the expected operating values exceeds a threshold, the controller (500) provides a flag to indicate that a short circuit condition exists.

Abstract: A controller (500) in an electric drive system is used to determine the operating condition of array of rotating diodes (302B) within a generator (204). During operation, the controller (500) receives a set of generator inputs, a set of machine parameters, and a set of diagnostic values. Next, the controller (500) determines a set of expected operating values corresponding to the set of diagnostic values. The controller (500) then compares the obtained diagnostic values to one or more corresponding expected operating values. If the difference is greater than a threshold, the controller (500) provides a fault indication that one or more of the array of rotating diodes (302B) has malfunctioned.