A method of controlling a motor, for example of an electric power steering system, includes receiving a motor torque demand signal indicative of a torque required from the motor. A current demand signal indicative of the currents to be applied to each phase to meet the torque demand is generated from the motor torque demand signal. One or more operational values from the motor are determined. The current demand signal is set as a function of one or more parameters of the motor obtained by fitting a flux linkage model to the measured operational values. A motor circuit having the permanent magnet electric motor includes a control stage arranged to generate the current demand signal in response to a torque demanded of the motor. A modifying means modifies the magnitude and/or the phase of the current demanded for each phase of the motor by the controller.

A method of controlling a motor, for example of an electric power steering system, includes receiving a motor torque demand signal indicative of a torque required from the motor. A current demand signal indicative of the currents to be applied to each phase to meet the torque demand is generated from the motor torque demand signal. One or more operational values from the motor are determined. The current demand signal is set as a function of one or more parameters of the motor obtained by fitting a flux linkage model to the measured operational values. A motor circuit having the permanent magnet electric motor includes a control stage arranged to generate the current demand signal in response to a torque demanded of the motor. A modifying means modifies the magnitude and/or the phase of the current demanded for each phase of the motor by the controller.

A rotating electric machine drive system includes: a rotating electric machine equipped with: a rotor having one magnetic pole configured by permanent magnets, and a salient pole portion that is magnetically convex in a radial direction; and a stator wound with a multiphase stator winding; an inverter for supplying electric power to the stator winding; and a control unit for controlling energization current of the inverters. The control unit performs energization control of the stator winding such that a fundamental wave current at a fundamental frequency synchronized with a rotational speed of the rotor, and a harmonic current that is triple the fundamental frequency flow in the stator winding, and such that energization of the harmonic current generates a stator magnetic field having a specified lead phase or delay phase with respect to a third-order magnetic field of the rotor.

A rotating electric machine drive system includes: a rotating electric machine equipped with: a rotor having one magnetic pole configured by permanent magnets, and a salient pole portion that is magnetically convex in a radial direction; and a stator wound with a multiphase stator winding; an inverter for supplying electric power to the stator winding; and a control unit for controlling energization current of the inverters. The control unit performs energization control of the stator winding such that a fundamental wave current at a fundamental frequency synchronized with a rotational speed of the rotor, and a harmonic current that is triple the fundamental frequency flow in the stator winding, and such that energization of the harmonic current generates a stator magnetic field having a specified lead phase or delay phase with respect to a third-order magnetic field of the rotor.

A rotating electrical machine includes a magnetic field-producing unit, an armature with a multi-phase armature winding, and a rotor. The magnetic field-producing unit includes a first portion and a second portion. The first portion is located closer to a d-axis in a d-q axis coordinate system than the second position is. The second position is located closer to a q-axis in the d-q axis coordinate system than the first position is. The magnetic field-producing unit is magnetically oriented to meet a condition where an angle which an easy axis of magnetization of the first portion makes with the d-axis is smaller than an angle which an easy axis of magnetization of the second portion makes with the q-axis. The magnetic field-producing unit is configured to have an intrinsic coercive force of 400 kA/m and also have a remanent flux density of 1.0 T or more.

A rotating electrical machine includes a magnetic field-producing unit, an armature with a multi-phase armature winding, and a rotor. The magnetic field-producing unit includes a first portion and a second portion. The first portion is located closer to a d-axis in a d-q axis coordinate system than the second position is. The second position is located closer to a q-axis in the d-q axis coordinate system than the first position is. The magnetic field-producing unit is magnetically oriented to meet a condition where an angle which an easy axis of magnetization of the first portion makes with the d-axis is smaller than an angle which an easy axis of magnetization of the second portion makes with the q-axis. The magnetic field-producing unit is configured to have an intrinsic coercive force of 400 kA/m and also have a remanent flux density of 1.0 T or more.

A motor control device including: an operation control part that generates a torque command based on an operation command, and controls a rotational position and/or rotational speed of the spindle; a current control part that generates an excitation current command to control secondary magnetic flux of the induction motor, and a torque current command to control torque of the induction motor based on the torque command; a change detection part that detects a change in operation command requiring increasing the secondary magnetic flux of the induction motor; a magnetic flux amplification part that performs magnetic flux amplification to temporarily increase the excitation current command or a magnetic flux command in the current control part, in a case of a change in the operation command being detected; and a gain change part that changes gain of the operation control part when performing magnetic flux amplification.

A motor control device including: an operation control part that generates a torque command based on an operation command, and controls a rotational position and/or rotational speed of the spindle; a current control part that generates an excitation current command to control secondary magnetic flux of the induction motor, and a torque current command to control torque of the induction motor based on the torque command; a change detection part that detects a change in operation command requiring increasing the secondary magnetic flux of the induction motor; a magnetic flux amplification part that performs magnetic flux amplification to temporarily increase the excitation current command or a magnetic flux command in the current control part, in a case of a change in the operation command being detected; and a gain change part that changes gain of the operation control part when performing magnetic flux amplification.

A boosting operation of a converter and the intermittent energization operation of an inverter are optimally performed in accordant with input or output. The power converter includes the converter capable of boosting a DC voltage outputted by switching operation alternately performing shorting and rectification; the inverter; an inverter capable of performing intermittent energization in which switching around zero cross of a motor current is turned off upon converting the DC voltage outputted by the converter into three-phase AC power; and a controller that controls the converter to perform boosting operation and the inverter to perform the boosting operation of the converter and the intermittent energization operation of the inverter linkingly.

The control device includes: a unit for receiving, for a time period, phase voltage setpoints forming a setpoint vector in vector space; a unit for selecting at least N+I states of the inverter which are associated, respectively, with at least N+I predetermined vectors (MI . . . M27) defining a volume in the vector space (Esp) containing the setpoint vector; a unit for controlling the inverter, over the time period, in order to place it successively in the selected states so that it substantially applies, on average over the time period, the phase voltage setpoints. The at least N+I states of the inverter are selected from among groups of at least N+I states of the inverter, the at least N+I states of the inverter of at least one of the groups being associated, respectively, with at least N+I predetermined vectors (MI . . . M27), at least N of which are formed by predetermined zero-sum phase voltages and at least one of which is formed by predetermined nonzero-sum phase voltages.