Abstract:
A method of controlling a motor is provided. The method may monitor a plurality of operational characteristics of the motor, determine an optimum transition speed of the motor based on the operational characteristics, and engage a transition of the motor between a current regulation mode of operation and a single pulse mode of operation at the optimum transition speed.
Abstract:
A method of controlling a generator (110) of an electric drive (104) associated with an engine (102) is provided. The method may determine an operational state of the electric drive (104) based on a speed of the engine (102), and selectively engage one of a map-lookup control scheme (150) and a fixed-theta off control scheme (152) for operating the generator (110) based on the operational state of the electric drive (104).
Abstract:
A field weakening control system for use with an induction motor is disclosed. The field weakening control system has a sensing device configured to generate a signal indicative of a speed of the induction motor and a controller. The controller is configured to determine an initial voltage command based on the signal and determine an acceleration of the induction motor based on the signal. The controller is also configured to generate a desired voltage command based on at least one of the initial voltage command and the acceleration.
Abstract:
A field weakening control system for use with an induction motor is disclosed. The field weakening control system has a sensing device configured to generate a signal indicative of a speed of the induction motor and a controller. The controller is configured to determine an initial voltage command based on the signal and determine an acceleration of the induction motor based on the signal. The controller is also configured to generate a desired voltage command based on at least one of the initial voltage command and the acceleration.
Abstract:
A method of controlling a generator (110) of an electric drive (104) associated with an engine (102) is provided. The method may determine an operational state of the electric drive (104) based on a speed of the engine (102), and selectively engage one of a map-lookup control scheme (150) and a fixed-theta off control scheme (152) for operating the generator (110) based on the operational state of the electric drive (104).
Abstract:
A method of priming a common bus of a machine having an engine, a generator and an auxiliary power source is provided. The method may determine an operational state of the auxiliary power source, operate the engine at a predetermined idle speed if the auxiliary power source is determined to be inoperative, and enable the generator to regulate the common bus in response to the predetermined idle speed of the engine.
Abstract:
A method of controlling a motor is provided. The method may determine a speed of the motor, and engage a soft chopping routine on a first switch and a second switch of each phase if the motor speed is relatively low. The first switch may be driven by a first pulse width modulated PWM signal and the second switch being driven by a second PWM signal. The first and second PWM signals may be alternatingly configured such that at least one of the first switch and the second switch is closed at any point during the distributed soft chopping routine and both the first switch and the second switch are never simultaneously open.
Abstract:
A method of actively discharging a common bus (116) of a machine (100) having an engine (102), a generator (112), a traction motor (124) and one or more auxiliary devices (126) is provided. The method may monitor a speed of the engine (102) with respect to a first threshold, monitor a voltage of the common bus (116) with respect to a second threshold, and enable one or more of the generator (112), the motor (124) and the auxiliary devices (126) if the engine speed falls below the first threshold and the voltage exceeds the second threshold so as to discharge voltage from the common bus (116).
Abstract:
A protection circuit includes a first switch, a second switch and a third switch. The first switch, the second switch and the third switch are configured to generate lock signals indicative of an electrical voltage transition on the respective phases of a multi-phase power signal. A control circuit is configured to prevent the first switch from changing state if the second switch or third switch is changing state.
Abstract:
A method of estimating rotor speed of a generator 106 having a rotor 110 and a stator 112 is provided. The method may provide a source current to the stator 112, determine a relative rotor speed based on a sensor signal provided by a rotor speed sensor 130, determine a relative rotor position corresponding to the relative rotor speed, determine an absolute rotor position based on the sensor signal and phase currents, and calibrate the sensor signal based on an offset between the relative rotor position and the absolute rotor position.