A method of starting-up a switched reluctance, SR, motor is provided. The method comprises simultaneously energizing a plurality of phases at a first time point with respective phase voltages that are substantially the same, until the motor rotor is stabilized in alignment with either one of the plurality of phases; simultaneously de-energizing the plurality of phases at a second time point that follows the first time point; monitoring a decrease of respective phase currents in the plurality of phases from a third time point that follows the second time point by a first predetermined time interval; determining a phase of alignment of the rotor using evaluation of the decrease of the phase currents following simultaneous de-energizing of the plurality of phases; and, initiating rotation of the rotor from the determined phase of alignment of the rotor.

A four-phase switched reluctance motor torque ripple two-level suppression method. A first set of torque thresholds is set in rotor position interval [0°, θr/4]. A second set of torque thresholds is set in rotor position interval [θr/4, θr/2]. Power is supplied to adjacent phase A and phase B for excitation. The power supplied for excitation to phase A leads the power supplied for excitation to phase B by θr/4. An entire commutation process from phase A to phase B is divided into two intervals. In rotor position interval [0°, θ1], phase A uses the second set of torque thresholds while phase B uses the first set of torque thresholds. Critical position θ1 automatically appears in the commutation process, thus obviating the need for additional calculations. Total torque is controlled between [Te+th2low and Te+th2up]. In rotor position interval [θ1, θr/4], phase A continues to use the second set of torque thresholds, phase B continues to use the first set of torque thresholds, and the total torque is controlled between [Te+th1low and Te+th1up]. This suppresses torque ripples of a four-phase switched reluctance motor and provides great engineering application values.

A four-phase switched reluctance motor torque ripple two-level suppression method. A first set of torque thresholds is set in rotor position interval [0°, θr/4]. A second set of torque thresholds is set in rotor position interval [θr/4, θr/2]. Power is supplied to adjacent phase A and phase B for excitation. The power supplied for excitation to phase A leads the power supplied for excitation to phase B by θr/4. An entire commutation process from phase A to phase B is divided into two intervals. In rotor position interval [0°, θ1], phase A uses the second set of torque thresholds while phase B uses the first set of torque thresholds. Critical position θ1 automatically appears in the commutation process, thus obviating the need for additional calculations. Total torque is controlled between [Te+th2low and Te+th2up]. In rotor position interval [θ1, θr/4], phase A continues to use the second set of torque thresholds, phase B continues to use the first set of torque thresholds, and the total torque is controlled between [Te+th1low and Te+th1up]. This suppresses torque ripples of a four-phase switched reluctance motor and provides great engineering application values.

Power based self-sensing of a rotor position of an SR motor at mid to high speeds and low torque is achieved by an SR motor control system by comparing the motor power to an injection maximum power. A position current pulse is injected to a stator pole in response to the motor power being less than the injection maximum power. An actual stator current created by the position current pulse is compared to an estimated stator current, and a stored estimated rotor position in a memory is updated to a new estimated rotor position if the actual stator current is not equal to the estimated stator current.

Power based self-sensing of a rotor position of an SR motor at mid to high speeds and low torque is achieved by an SR motor control system by comparing the motor power to an injection maximum power. A position current pulse is injected to a stator pole in response to the motor power being less than the injection maximum power. An actual stator current created by the position current pulse is compared to an estimated stator current, and a stored estimated rotor position in a memory is updated to a new estimated rotor position if the actual stator current is not equal to the estimated stator current.

A monitoring device for a reluctance machine includes a vector rotator for rotating a space phasor of the reluctance machine that depends on a voltage in a coordinate system that rotates with a negative fundamental frequency, a low-pass filter filtering the rotated space phasor and producing an output signal, and a signal evaluation device evaluating the output signal. A DC value of the produced output signal in the rotating coordinate system is monitored, and an error in operating the reluctance machine is identified when the DC value is above a predefined threshold value.

A monitoring device for a reluctance machine includes a vector rotator for rotating a space phasor of the reluctance machine that depends on a voltage in a coordinate system that rotates with a negative fundamental frequency, a low-pass filter filtering the rotated space phasor and producing an output signal, and a signal evaluation device evaluating the output signal. A DC value of the produced output signal in the rotating coordinate system is monitored, and an error in operating the reluctance machine is identified when the DC value is above a predefined threshold value.

A system and method for torque compensation in a switched reluctance (SR) machine disposed on a machine is disclosed. The system may comprise a SR machine, an inverter and a controller. The controller is in operable communication with the inverter and is configured to determine a commanded main current associated with energization by a main current of a first portion of the plurality of windings for a controlling phase, and determine a commanded parasitic current associated with energization by a parasitic current of a second portion of the windings in a non-controlling phase. The controller is further configured to determine an offset current based on the commanded parasitic current, and determine a target current based on a first sum of the commanded main current and the offset current, and command the inverter to actuate the target current in the first portion of the windings during the controlling phase.

A method and apparatus for quasi-sensorless adaptive control of a high rotor pole switched-reluctance motor (HRSRM). The method comprises the steps of: applying a voltage pulse to an inactive phase winding and measuring current response in each inactive winding. Motor index pulses are used for speed calculation and to establish a time base. Slope of the current is continuously monitored which allows the shaft speed to be updated multiple times and to track any change in speed and fix the dwell angle based on the shaft speed. The apparatus for quasi-sensorless control of a high rotor pole switched-reluctance motor (HRSRM) comprises a switched-reluctance motor having a stator and a rotor, a three-phase inverter controlled by a processor connected to the switched-reluctance motor, a load and a converter.

A method and apparatus for quasi-sensorless adaptive control of a high rotor pole switched-reluctance motor (HRSRM). The method comprises the steps of: applying a voltage pulse to an inactive phase winding and measuring current response in each inactive winding. Motor index pulses are used for speed calculation and to establish a time base. Slope of the current is continuously monitored which allows the shaft speed to be updated multiple times and to track any change in speed and fix the dwell angle based on the shaft speed. The apparatus for quasi-sensorless control of a high rotor pole switched-reluctance motor (HRSRM) comprises a switched-reluctance motor having a stator and a rotor, a three-phase inverter controlled by a processor connected to the switched-reluctance motor, a load and a converter.