In sensorless control for a rotary machine, when variations in inductances for U, V, W phases due to manufacturing error are great, imbalance occurs among detected currents for the respective phases. Thus, estimation error of a magnetic pole position of a rotor increases, so that positioning accuracy is reduced. Correction filters for imparting gains in accordance with rotary machine constants for the respective phases are provided to control means or magnetic pole position calculation means, thereby correcting the imbalance occurring among the detected currents for the respective phases.

A method of controlling a brushless permanent-magnet motor having a phase winding and a rotor, includes applying voltages of first and second opposing polarities to the phase winding when the rotor is oscillating about a parking position, measuring a plurality of first times, each first time including a time taken for current flowing through the phase winding in response to an applied voltage of the first polarity to exceed a threshold and measuring a plurality of second times, each second time including a time taken for current flowing through the phase winding in response to an applied voltage of the second polarity to exceed the threshold. The method includes determining which of an average magnitude of the plurality of first times and an average magnitude of the plurality of second times has the smaller average magnitude, and determining an amplitude peak of the plurality of times having the smaller average magnitude. The method includes using the amplitude peak to calculate a time window, setting a timer corresponding to the time window at a subsequent determined amplitude peak, and applying a drive voltage to the phase winding during the time window.

Examples include a method for controlling a synchronous motor using a variable speed drive. The motor includes a permanent magnet rotor generating a magnetic flux. The method includes applying a predefined electrical command signal to the motor and estimating a motor speed in response to the applying of the predefined electrical command signal. The method also includes reaching a desired estimated motor speed and, in response to reaching the desired estimated motor speed, estimating a parameter related to the magnetic flux of the permanent magnet rotor. The method further includes recording the estimated parameter.

Provided is a motor control apparatus that suppresses a steep rush current to a charging circuit and that can quickly start driving of a motor without depending on a current-limiting resistor. The motor control apparatus according to the present disclosure includes an inverter for driving a motor, a charging circuit for supplying electric power to the inverter, a relay circuit for connecting a charging circuit and a power supply terminal, a control unit for controlling the inverter and the relay circuit, and a pre-charging circuit that is provided in parallel with the relay circuit, that starts charging from the power supply terminal to the charging circuit after a power switch for connecting an external power source with the power supply terminal is turned on, and that completes charging of the charging circuit before the control unit starts operation thereof.

A drive unit attached to a mobile entity is disclosed. The drive unit includes a motor, a first detector, and a controller. The first detector detects vehicle speed information regarding a vehicle speed of the mobile entity. The controller performs PWM control for the motor. The controller controls a duty cycle of a PWM signal in accordance with the vehicle speed information detected by the first detector.

A system and method for identifying and responding to a condition in which an electric motor fails to start. A rotor core includes slots in which magnets are received to produce an electrical reluctance. A motor controller determines a position of the rotor, uses the determined position to convert a torque demand to a demanded D-axis current value, and compares the demanded value to a supplied D-axis current value. If the demanded value differs from the supplied value by at least a pre-established threshold amount, then the motor is restarted. Otherwise, the difference between the torque demand and an actual current is used to drive a voltage applied to the motor. The controller may also implement a sensorless technology, and may restart the motor if the demanded value differs from the supplied value by at least the threshold amount even if the sensorless technology determines that the motor started.

A contactless power supply and motor control system includes a pulse width modulator, a rotary transformer, a demodulator circuit, a motor driver, and a motor. The pulse width modulator supplies a first pulse width modulated (PWM) signal that has a duty cycle and a first amplitude. The rotary transformer receives the PWM signal. The secondary winding is rotatable relative to the primary winding and supplies a second PWM signal having the duty cycle and a second amplitude. The demodulator circuit is rotatable with the secondary winding and supplies a demodulated direct current (DC) voltage having a DC voltage amplitude. The motor driver is rotatable with the secondary winding and the demodulator circuit and controllably supplies motor current. The motor receives the motor current and rotates at a rotational speed.

A control system may include a processor that may receive a first dataset associated with a current received at a load device coupled to a relay device. The processor may also determine harmonics data associated with the current and determine a switching profile to control moving a first armature of three armatures in the relay device based on the harmonics data. The switching profile is configured to control movement of the first armature between a first position and a second position, and wherein the switching profile comprises a firing angle for moving the first armature with respect to an electrical waveform, a second armature, and a third armature. The processor may then control a current provided to a relay coil of the relay device based on the switching profile, such that the relay coil causes the first armature to move.

Methods and systems are provided for adaptive pulse width modulated control of an electrified powertrain of a vehicle. In one example, a method may include perturbing a switching frequency for pulse width modulated control of the electrified powertrain, and, responsive to sound measured in a vehicle cabin indicating a noise improvement after the perturbation, controlling the electrified powertrain with the perturbed switching frequency. In this way, acoustic emissions from an electrified powertrain may be reduced.

A method of operating an electric or hybrid system comprising a synchronous reluctance electric motor coupled to an electric or hybrid powertrain is described herein. The method comprises determining (i) a torque demand required of the electric motor and (ii) a speed of rotation of the rotor of the electric motor, and storing kinetic energy in a rotor of the electric motor from the powertrain in response to at least one of (i) the determined torque demand falling below a selected torque demand threshold and (ii) the speed of the rotor being below a selected rotor speed threshold. The method further comprises operating the electric motor by powering the electric motor with electricity to deliver energy to the powertrain in response to at least one of: (i) the determined torque demand rising above a selected torque demand threshold and (ii) the speed of the rotor falling below a selected rotor speed threshold.