Abstract: A method for detecting a phase imbalance of an electrical component in a machine due to an actual fault is provided. The method includes receiving electrical parameter values associated with a plurality of phases of an electrical component, detecting a phase imbalance in the plurality of phases, calculating an imbalance ratio of the plurality of phases, applying a plurality of conditions to the imbalance ratio and to the received input vector, the plurality of conditions being associated with an actual fault in the machine, and determining whether the detected phase imbalance is due to a controls induced imbalance in the machine or due to the actual fault in the electrical component of the machine when at least one of the plurality of conditions is met.

Abstract: A method for detecting a phase imbalance of an electrical component in a machine due to an actual fault is provided. The method includes receiving electrical parameter values associated with a plurality of phases of an electrical component, detecting a phase imbalance in the plurality of phases, calculating an imbalance ratio of the plurality of phases, applying a plurality of conditions to the imbalance ratio and to the received input vector, the plurality of conditions being associated with an actual fault in the machine, and determining whether the detected phase imbalance is due to a controls induced imbalance in the machine or due to the actual fault in the electrical component of the machine when at least one of the plurality of conditions is met.

Abstract: The present disclosure is related to a method to control a contactor tip assembly associated with a grid of an electric drive system is provided. The contactor tip assembly includes at least one first contactor tip and at least one second contactor tip. The method includes introducing a delay signal associated with an operation of at least one of the first contactor tip and the second contactor tip. Further, the operation includes a closing event and an opening event thereof. The method also includes controlling the operation of the first and second contactor tips in an alternate manner. Further, a delay is present between a sequential operation of one of the first and second contactor tips and the other of the first and second contactor tips based, at least in part, on the introduced delay signal.

Abstract: A rotary position sensor includes a rotatable disk, a first light sensor configured to generate a first opacity signal, a second light sensor configured to generate a second opacity signal, and a comparator. The opacity of the rotatable disk is substantially unique at each radial angle value. The comparator is configured to generate a disk position signal as a function of the first opacity signal and the second opacity signal.

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: The disclosure describes, in one aspect, a system for a machine having an electric drive configuration. The system includes an electric motor associated with at least one wheel and adapted to provide retarding torque to the wheel, and a controller configured to determine a power measurement of a retarding grid and control the retarding torque to the at least one wheel during retarding as a function of the power measurement.

Abstract: The disclosure describes, in one aspect, a system for a machine having an electric drive configuration. The system includes an electric motor associated with at least one wheel and adapted to provide retarding torque to the wheel, and a controller configured to determine a power measurement of a retarding grid and control the retarding torque to the at least one wheel during retarding as a function of the power measurement.

Abstract: A rotary position sensor includes a rotatable disk, a first light sensor configured to generate a first opacity signal, a second light sensor configured to generate a second opacity signal, and a comparator. The opacity of the rotatable disk is substantially unique at each radial angle value. The comparator is configured to generate a disk position signal as a function of the first opacity signal and the second opacity signal.

Abstract: A cooling system for a retarding system of an electric drive machine (100) includes a direct current (DC) link having first and second rails. A first resistor grid (214) is selectively placed in circuit between the rails by an automatic switch (216) in response to a switch (216) signal. A second resistor grid (218) is selectively placed in circuit between the rails by a chopper circuit (220) connected in series with the second resistor grid (218). The chopper modulates a current passing therethrough based on a duty cycle. A motor (336) is in parallel electrical connection across a portion of the first resistor grid (214) and operates in response to a motor (336) signal. An electronic controller (400) calculates a net energy during operation and adjusts the switch (216) signal, the duty cycle, and the motor (336) signal to close the automatic electrical switch (216) and operate the motor (336) when the net energy exceeds a threshold value.

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 cooling system for a retarding system of an electric drive machine (100) includes a direct current (DC) link having first and second rails. A first resistor grid (214) is selectively placed in circuit between the rails by an automatic switch (216) in response to a switch (216) signal. A second resistor grid (218) is selectively placed in circuit between the rails by a chopper circuit (220) connected in series with the second resistor grid (218). The chopper modulates a current passing therethrough based on a duty cycle. A motor (336) is in parallel electrical connection across a portion of the first resistor grid (214) and operates in response to a motor (336) signal. An electronic controller (400) calculates a net energy during operation and adjusts the switch (216) signal, the duty cycle, and the motor (336) signal to close the automatic electrical switch (216) and operate the motor (336) when the net energy exceeds a threshold value.