Abstract: Methods and systems for operating a vehicle are provided. In one example, a method for operating a vehicle may include flowing compressed gas selectively through distinct orifice sizes depending on an operating condition of the vehicle. In another example, the vehicle may be a rail vehicle. In one example, the compressed gas may include compressed ambient air, and where the compressed gas is selectively delivered toward an upstream of a vehicle wheel riding on a rail via a nozzle. In another example, the compressed gas may be selectively delivered through a first orifice and not a second orifice to the nozzle during a first condition, and delivered through the second orifice and not the first orifice during a second condition different from the first condition.

Abstract: A system includes a sensor and a controller. The sensor is configured to detect sliding of a wheel of a vehicle. The controller is configured to communicate with the sensor and a traction motor operatively connected to the wheel such that the traction motor selectively applies forces in at least one direction to the wheel during operation. The controller is further configured to direct the traction motor to apply a motoring slide reducing force to the wheel when the sensor detects sliding of the wheel resulting from a frictional braking force.

Abstract: A system includes a sensor and a controller. The sensor is configured to detect sliding of a wheel of a vehicle. The controller is configured to communicate with the sensor and a traction motor operatively connected to the wheel such that the traction motor selectively applies forces in at least one direction to the wheel during operation. The controller is further configured to direct the traction motor to apply a motoring slide reducing force to the wheel when the sensor detects sliding of the wheel resulting from a frictional braking force.

Abstract: A control method comprises determining wheel creep of a wheel operably coupled to a traction motor and limiting a rate of change of an excitation frequency applied to the traction motor to drive the wheel, based on the determined wheel creep. According to one aspect, the rate of change of the excitation frequency is limited if the wheel creep exceeds a wheel creep threshold.

Abstract: A traction control system for controlling an electric traction motor drivingly coupled to a wheel of a tractive vehicle. The traction control system includes means for determining speed of the wheel, means for determining tractive effort of the wheel and a control circuitry for controlling drive signals to the motor based upon the wheel speed and tractive effort.

Abstract: A method and system is provided for detecting and performing diagnostics regarding an incipient ground fault that may occur in an electrical propulsion system of a traction vehicle, such as a locomotive, transit vehicle, or off-highway vehicle. The method allows providing a first ground connection for the electrical propulsion system. This first ground connection forms a grounding path generally used by the electrical propulsion system during normal operation. The method further allows providing a second ground connection for the electrical propulsion system. This second ground connection forms a grounding path selectively usable in lieu of the first ground connection. A control strategy is defined for switching between the first ground connection and the second ground connection. A respective leakage current associated with at least one of the first and second ground connections may be monitored.

Abstract: A method for detecting electrical faulty conditions in a plurality of power devices of a propulsion system is provided. The plurality of power devices is connectable in parallel circuit through a direct current (DC) link to an external DC power source. The method provides a first sequence of actions for determining an electrical short condition in at least one of the power devices upon the power source being connected. The method further provides a second sequence of actions for determining an electrical open condition in a respective one of the plurality of power devices during the occurrence of high current events.

Abstract: A method for detecting electrical faulty conditions in a plurality of power devices of a propulsion system is provided. The plurality of power devices is connectable in parallel circuit through a direct current (DC) link to an external DC power source. The method provides a first sequence of actions for determining an electrical short condition in at least one of the power devices upon the power source being connected. The method further provides a second sequence of actions for determining an electrical open condition in a respective one of the plurality of power devices during the occurrence of high current events.