A steering control device includes an electronic control unit configured to calculate a d-axis current command value and a q-axis current command value for a motor having three phases configured to generate drive power applied to a shaft interlocked with turning wheels, to convert detected current values in the phases of the motor to a d-axis current value and a q-axis current value, and to perform feedback control. The electronic control unit is configured to perform field weakening control for setting the d-axis current command value to a negative value based on a rotation speed of the motor, to determine whether the motor is in a regenerative state, and to calculate the d-axis current command value according to the regenerative state of the motor when the electronic control unit determines that the motor is in the regenerative state.

An apparatus for controlling a variable magnetic flux motor, wherein the variable magnetic flux motor includes a rotor in which a permanent magnet and a conductor bar are arranged, includes an inverter configured to apply a stator current to a stator coil of the motor, and a control unit configured to control a torque of the conductor bar and magnetize or demagnetize the permanent magnet by controlling the stator current through the inverter.

There is provided herein a method of advancing phase of a DQ reference frame in a Field Oriented Control, FOC, algorithm for a permanent magnet motor. The method comprises: monitoring a component of the stator voltage demand of the permanent magnet motor, when the component of the stator voltage demand surpasses a threshold, calculating a phase advance angle, θ.sub.adv, based on a gain multiplied by the difference between the component of stator voltage demand and the threshold; and advancing phase of the DQ reference frame in the FOC algorithm based on the calculated phase advance angle, up to a maximum phase advance angle when motor speed is positive, or down to a minimum phase angle when motor speed is negative.

The present disclosure provides a predictive control method of current increment for a permanent magnet synchronous motor includes: substituting a mathematical expression of a stator voltage during one control period into a continuous time domain current model to obtain a discrete current prediction model and a predicted current at the next time point; obtaining a predicted current increment from a current increment prediction model by subtracting a predictive current at a present time point from a predictive current at a next time point; establishing a cost function according to a preset reference current increment and the predicted current increment; obtaining an optimal voltage increment by minimizing the cost function; superposing the optimal voltage increment on a stator voltage of a present control period to obtain an optimal stator voltage of a next control period for controlling control the permanent magnet synchronous motor.

An electric motor drive apparatus comprising a voltage converter component arranged to receive a supply voltage signal and output a bus voltage signal, and a motor driver component arranged to receive the bus voltage signal and generate at least one drive signal for an electric motor from the bus voltage signal. The motor driver component is arranged to output a bus voltage feedback signal to the voltage converter component. The voltage converter component is arranged to regulate a voltage level of the bus voltage signal based at least partly on the bus voltage feedback signal output by the motor driver component.

An apparatus for controlling an inverter to drive a motor includes: a current control processor generating a voltage command for generating d/q axis current detection values, which are obtained by measuring current supplied to the motor, to follow a d/q axis current command for driving the motor, the current control processor converting the voltage command, which is sampled according to a sampling frequency generated based on a voltage vector phase of the voltage command, into a voltage vector corresponding to a point on each vertex and each side of a hexagon in a voltage vector diagram to apply a resulting value to the inverter driving the motor; and a sample frequency computing processor computing the sampling frequency based on the voltage vector phase of the voltage command and a reference number of sampling times during one rotation period of the motor.

An electric motor control device that drives and controls a plurality of electric motors connected in parallel, includes: a power conversion device; a current detection device; and a controller that includes a first control unit to perform first control on each of the plurality of electric motors based on the electric current, a second control unit to perform second control of controlling the plurality of electric motors such that an estimated speed of each of the plurality of electric motors obtained based on the current value follows the speed command value, and a switching determination unit to perform switching determination processing of switching between the first control performed by the first control unit and the second control performed by the second control unit according to drive information on at least one or more of the plurality of electric motors.

A steering control device includes an electronic control unit configured to calculate a d-axis current command value and a q-axis current command value for a motor having three phases configured to generate drive power applied to a shaft interlocked with turning wheels, to convert detected current values in the phases of the motor to a d-axis current value and a q-axis current value, and to perform feedback control. The electronic control unit is configured to perform field weakening control for setting the d-axis current command value to a negative value based on a rotation speed of the motor, to determine whether the motor is in a regenerative state, and to calculate the d-axis current command value according to the regenerative state of the motor when the electronic control unit determines that the motor is in the regenerative state.

A current controller is provided having a positive sequence controller and at least one negative sequence controller, where one or more error signals operated on by the positive sequence controller are transformed into at least one sequence reference frame and input to the at least one negative sequence controller with at least one targeted harmonic set by a harmonic factor value.

A method (as implemented in a current controller) is provided for higher bandwidth operation based on minimized interference between positive and negative components of a current controller, where the method may be performed without additional filtering on measured currents to isolate positive and negative current components. The method involves: identifying one or more error signals operated on by a positive sequence controller; transforming the one or more error signals into at least one negative sequence reference frame associated with at least one negative sequence controller; inputting transformed error signals to the negative sequence controller, where undesirable interactions between the positive sequence controller and negative sequence controller is minimized by sharing error signals.