In the position sensorless control method in low-speed region of the fault-tolerant permanent magnet motor system based on the envelope detection and the non-orthogonal phase-locked loop of the present disclosure, the position sensorless control of the motor is implemented by injecting the high-frequency voltage signals into any two non-faulty phase windings of the motor, extracting the high-frequency response currents of the high-frequency injected phases by the digital bandpass filter, calculating the differential mode inductances of the two phase windings through the envelope detecting and signal processing, and extracting the rotor position and rotational speed signals from the estimated two phase inductances through the non-orthogonal phase-locked loop. In addition, the controller of the present disclosure is small in size, high in accuracy, and high in reliability, which can effectively meet the performance requirements of the onboard electric actuators.

A method for determining an interrupted motor phase of an electric motor having at least three windings by means of a control unit is disclosed, wherein voltages induced in the windings are determined on outer conductors of the electric motor by means of at least one measuring unit, wherein the measuring unit is connected to at least one outer conductor of the electric motor via at least one resistor, the induced voltages of the outer conductors of the electric motor are compared with one another, and an interrupted motor phase is registered if the induced voltage differs or if a frequency of the induced voltage differs. A control unit, a computer program and a machine-readable storage medium are also disclosed.

A system and method for reliable control of a high rotor pole switched reluctance machine (HRSRM) utilizing a sensorless reliable control system. The method comprising: energizing at least one of the plurality of stator phases; measuring a first current value and time taken by the first current value to reach a first peak value or preset threshold value of current; determining a self-inductance value; measuring a second current value and time taken by an adjacent un-energized stator phase to reach a second peak value of current; determining a mutual inductance value; and estimating a rotor position utilizing the self-inductance and mutual inductance values; and controlling the HRSRM based on the estimated rotor position.

An MPU sequentially selects one from six energization patterns, applies constant voltage rectangular pulses to the three-phase coils for a prescribed sensing energization time, turns on at least the low-side arm of the three-phase half-bridge type inverter circuit so as to reflux an induced current between a switching element and the coils and attenuate the same, measures peak coil current values immediate before completing the sensing energization by an A/D-converter circuit, and stores the peak coil current values as measured data.

A device for estimating inductances of an electric machine having a salient-pole rotor is presented. The device comprises a processing system that controls stator voltages to constitute a balanced multi-phase alternating voltage when the rotor is stationary. The processing system estimates a position of the rotor based on a negative sequence component of stator currents. To estimate the quadrature-axis inductance, the processing system controls direct-axis current to be direct current and quadrature-axis voltage to be alternating voltage. The quadrature-axis inductance is estimated based on the quadrature-axis alternating voltage and on quadrature-axis alternating current. To estimate the direct-axis inductance, the processing system controls direct-axis voltage to be alternating voltage and the quadrature-axis voltage to be zero. The direct-axis inductance is estimated based on the direct-axis alternating voltage and on direct-axis alternating current.

A motor control apparatus 1 includes a fixed phase setting section that sets a fixed phase of a motor according to a detection signal. At the start of rotation of a rotor, the fixed phase setting section sets a first fixed phase that is equal to or greater than 90 degrees relative to a stable stopping point at a maximum electrical angle and is equal to or less than 90 degrees relative to a stable stopping point at a minimum electrical angle of the rotor as the fixed phase, and sets a second fixed phase that is equal to or greater than 90 degrees relative to a stable stopping point at a maximum electrical angle and is equal to or less than 90 degrees relative to a stable stopping point at a minimum electrical angle of the rotor.

A motor control apparatus includes: a voltage control unit configured to control a voltage applied to a plurality of coils in a motor to supply an exciting current; a current detection unit configured to detect an exciting current having flown through the plurality of coils; and a detection unit configured to detect a stop position of a rotor of the motor by performing a detection process, in which the exciting current to at least a first coil of the plurality of coils is supplied by the voltage control unit, and the exciting current is detected by the current detection unit. The detection process includes a first period in which a first voltage of a first polarity is applied to the first coil, and a second period in which a second voltage of a second polarity is applied to the first coil.

A method for controlling switched reluctance machine (SRM) utilizing a SRM control system. The method allows for adaptive pulse positioning over a wide range of speeds and loads. An initial rotor position is provided for the SRM utilizing an initialization mechanism. A pinned point on a phase current waveform is defined during an initial current rise phase of the current waveform. A slope of the current rise is determined as the current waveform reaches the pinned point. The slope is then fed to the commutation module of the SRM control system. An error signal from calculated inductance or current slope is used as an input to a control loop in the SRM control system. The time determining module determines an optimum time signal to fire a next pulse. The optimum time signal is fed to the SRM for turning the plurality of SRM switches to on and off states.

The present invention addresses the problem of providing a method for detecting magnetic field location which can realize low cost by using simple hardware and software and can detect a rotor location in units of excitation sections in 120-energization without generating sensing noise at the time of initiation. As a solution, an MPU (51) obtains, through calculation, a neutral point potential from an energization-phase voltage measured by an A/D conversion circuit (53), obtains the difference between the neutral point potential and a non-energization-phase voltage, performs magnitude comparison between the difference and a negative-side threshold value in the case where the present location is an odd-numbered section or between the difference and a positive-side threshold value in the case where the present location is an even-numbered section, and determines the end point of the 60-energization section when the difference exceeds a threshold value in a direction away from the neutral point potential.

A slotless synchronous permanent magnet motor includes a rotor, and a stator configured to electromagnetically interact with the rotor. The rotor is provided with a first conductive metal layer configured to create harmonic rotor saliency.