A control unit applied to a motor that includes a rotor having a field winding and a rotor having armature winding groups to control a field current passed through the field winding. Each of the armature winding groups is applied with a prescribed voltage. The field current is controlled so as to be a minimum field current value If_min with which a deviation between an amplitude of an induced voltage generated in the armature winding groups by rotation of the rotor, and an amplitude of the voltage applied to the armature winding groups becomes equal to or smaller than a prescribed value.

A control unit applied to a motor that includes a rotor having a field winding and a rotor having armature winding groups to control a field current passed through the field winding. Each of the armature winding groups is applied with a prescribed voltage. The field current is controlled so as to be a minimum field current value If_min with which a deviation between an amplitude of an induced voltage generated in the armature winding groups by rotation of the rotor, and an amplitude of the voltage applied to the armature winding groups becomes equal to or smaller than a prescribed value.

A rotary machine control device includes: a magnetization characteristics determiner that determines a magnet phase of a magnet flux based on an estimated magnetic flux and a detection current, and determines a qm-axis magnetic flux of the estimated magnetic flux, a qm-axis current of the detection current, and a harmonic component of a magnet phase using a dm-qm coordinate system with a dm axis representing the magnet phase and a qm axis representing a phase shifted by 90 degrees from the magnet phase; a ripple compensation determiner that determines a ripple compensation phase using a ripple compensation torque obtained based on the qm-axis current and the harmonic component; a command phase determiner that determines a command phase based on the ripple compensation phase and a torque command; and a command magnetic flux generator that generates a command magnetic flux based on a command amplitude and the command phase.

A rotary machine control device includes: a magnetization characteristics determiner that determines a magnet phase of a magnet flux based on an estimated magnetic flux and a detection current, and determines a qm-axis magnetic flux of the estimated magnetic flux, a qm-axis current of the detection current, and a harmonic component of a magnet phase using a dm-qm coordinate system with a dm axis representing the magnet phase and a qm axis representing a phase shifted by 90 degrees from the magnet phase; a ripple compensation determiner that determines a ripple compensation phase using a ripple compensation torque obtained based on the qm-axis current and the harmonic component; a command phase determiner that determines a command phase based on the ripple compensation phase and a torque command; and a command magnetic flux generator that generates a command magnetic flux based on a command amplitude and the command phase.

A method, system, and apparatus are provided for determining mechanical characteristics of an electric motor and mechanical load with a speed signal modulator, FOC current loop, sensor-less rotor speed estimator, and speed signal demodulator which are configured to provide a q-axis AC reference current, q-axis DC reference current, estimated maximum AC rotor speed, estimated DC rotor speed, estimated phase angle of the AC rotor speed component, and torque constant to a mechanical characteristics estimator which is configured to determine a plurality of load torque parameters for the electric motor and mechanical load which include a combined moment of inertia parameter, a combined static friction, and a combined viscous friction coefficient parameter.

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 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.

Reduced computation time for model predictive control (MPC) of a five level dual T-type drive considering the DC link capacitor balancing, the common-mode voltage (CMV) along with torque control of an open-ends induction motor based on determining a reduced set of switching states for the MPC. The reduced set of switching states are determined by considering either CMV reduction (CMVR) or CMV elimination (CMVE). Cost function minimization generates a voltage vector, which is used to produce gating signals for the converter switches. The reduced switching state MPC significantly reduces computation time and improves MPC performance.

Reduced computation time for model predictive control (MPC) of a five level dual T-type drive considering the DC link capacitor balancing, the common-mode voltage (CMV) along with torque control of an open-ends induction motor based on determining a reduced set of switching states for the MPC. The reduced set of switching states are determined by considering either CMV reduction (CMVR) or CMV elimination (CMVE). Cost function minimization generates a voltage vector, which is used to produce gating signals for the converter switches. The reduced switching state MPC significantly reduces computation time and improves MPC performance.

A motor flux weakening control method with data map creation is provided. The method estimates a phase angle between a dq electric current vector and a d-axis based on a speed of the motor; estimates an input direct current; repeats the estimating of the phase angle and the direct current while decreasing a magnitude of the dq electric current vector based on a difference between the estimated direct current and a preset direct current limitation value; and interrupts the repeating of the estimating of the phase angle and the estimating of the direct current when the direct current and the preset direct current limitation value are equal, and stores a relationship between the speed of the motor, the direct current voltage, the phase angle, and the magnitude of the dq electric current vector, when the estimated direct current and the preset direct current limitation value are equal.