To provide a rotary electric machine apparatus which can perform current control which reduces a torque ripple component effectively, using a rotary electric machine in which the permanent magnet of the rotor has the skew structure which shifts the magnetic pole position in the circumferential direction at each position in the axial direction. When defining, as the current vector of most advanced phase, a current vector of current command values calculated on the dq-axis rotating coordinate system of most advanced phase, and defining, as the current vector of middle phase, a current vector of current command values calculated on the dq-axis rotating coordinate system of middle phase, the rotary electric machine apparatus brings a controlling current vector close to the current vector of most advanced phase from the current vector of middle phase, as the winding currents increase.

The present disclosure relates to a motor assembly and a method for controlling the motor assembly. The motor assembly is characterized by comprising: a stator having a plurality of slots; a first coil and a second coil isolated from the first coil, the first and second coils being wound on each of the plurality of slots such that three-phase alternating currents are applied thereto; a rotor rotated by rotation magnetic fields generated by the first coil and the second coil; a first inverter unit for controlling the three-phase alternating current which is applied to the first coil in order to generate the rotation magnetic field; and a second inverter unit for controlling the three-phase alternating current which is applied to the second coil in order to generate the rotation magnetic field. Control signals for turning on and off the three-phase alternating currents applied to the first coil and the second coil are generated so as to be left-right symmetric by the first inverter unit and the second inverter unit during a preset switching cycle.

A motor control device of an embodiment includes a power supply unit that supplies AC power to a motor; a current detection unit that detects a current flowing through a winding of the motor; a speed and electric angle estimation unit that estimates a rotation speed and an electric angle of the motor based on a voltage outputted by the power supply unit and the current; a coordinate conversion unit that obtains an excitation current and a torque current based on the current and the electric angle; a torque current command determination unit that substitutes a predicted torque calculated based on a mechanical motion equation into a torque component current command value calculated based on a torque expression of a vector control coordinate, to generate a torque component current command value for bringing a difference between an inputted speed command and an estimated speed closer to zero; and a model prediction control unit that applies, to a plurality of predicted currents including a current change ratio determined depending on each of a plurality of switching patterns based on a space voltage vector that are able to be outputted by the power supply unit, an evaluation function to evaluate a size of a difference from a predicted current corresponding to each of the torque component current command value and an excitation component current command value inputted from outside, and that selects and outputs a switching pattern.

A first offset voltage which is added to voltage commands in a first three-phase voltage command calculated on the basis of a control command for an AC rotary machine, and a second offset voltage which is added to voltage commands in a second three-phase voltage command calculated on the basis of a control command for the AC rotary machine, are set in such a manner that a period during which one of a first power converter and a second power converter outputs an effective vector and the other thereof outputs a zero vector occurs during a carrier period of a first carrier wave signal and a second carrier wave signal.

The invention relates to a method (400) for calibrating a controller of an electric machine (120). The method comprises the following steps: specifying (410) a first signal (S_1) for generating a sinusoidal phase current for energising a winding of an electric machine (120); superposing (420) the first signal (S_1) with a test signal (S_Test_i) in order to generate a harmonic oscillation with a predetermined excitation amplitude and/or phase position relative to the phase current, which harmonic oscillation superposes the phase current; detecting (430) a response signal (S_Antw_i), resulting from the superposition of the phase current and the harmonic oscillation, by means of a sensor (130); determining (450) a calibrated signal (S_kal) for generating a harmonic oscillation with a predetermined excitation amplitude and a phase position relative to the phase current on the basis of a determined minimum of a response plane (A_Antw); operating (460) the controller (110) of the electric machine (120) on the basis of the determined minimum

Examples include a method for controlling a variable speed drive driving an electric motor. The variable speed drive is connected to an electric power source and comprises a passive DC-link and an inverter stage controlled by a first controller of the variable speed drive. The passive DC-link is connected to the inverter stage. The method comprises running the electric motor to reach a steady-state operating point, measuring a plurality of values of current or voltage of the passive DC-link, and computing, by a second controller, a frequency spectrum of the DC-link based on the plurality of values of current or voltage measured. The method further comprises detecting a specific resonance frequency by comparing amplitudes of the frequency spectrum to a predetermined pattern, and modifying filter parameters of a digital filter of the DC-link or control parameters of a control law of the electric motor based on the specific resonance frequency.

Disclosed herein is a drain pump driving apparatus and a laundry treatment machine including the same. The drain pump driving apparatus and the laundry treatment machine including the same according to an embodiment of the present invention include a motor to operate the drain pump, an inverter to convert a direct current (DC) power to an alternating current (AC) power by a switching operation and output the converted AC power to the motor, an output current detector to detect an output current flowing to the motor, and a controller to control the inverter, wherein the controller may calculate a speed ripple of the motor based on the output current and performs a control operation based on the calculated speed ripple of the motor to change a speed of the motor.

Disclosed herein is a drain pump driving apparatus and a laundry treatment machine including the same. The drain pump driving apparatus and the laundry treatment machine including the same according to an embodiment of the present invention include a motor to operate the drain pump, an inverter to convert a direct current (DC) power to an alternating current (AC) power by a switching operation and output the converted AC power to the motor, an output current detector to detect an output current flowing to the motor, and a controller to control the inverter, wherein the controller may calculate a speed ripple of the motor based on the output current and performs a control operation based on the calculated speed ripple of the motor to change a speed of the motor.

A motor drive device includes: a position command generator which generates a position command; a damping filter unit which includes one or more stages of damping filters which reduce vibration of a device including a load and a motor, applies, to a position command, a damping filter determined based on a model parameter corresponding to a model of the device, and outputs a filtered position command to which the damping filter has been applied; a servo controller which gives a torque command to the motor based on the filtered position command; a low-pass filter unit; a parameter estimation unit which estimates the model parameter from the rotational speed and the torque command of the motor which have passed through the low-pass filter unit; and a vibration determination unit which determines presence or absence of vibration in the model.

A motor drive device includes: a position command generator which generates a position command; a damping filter unit which includes one or more stages of damping filters which reduce vibration of a device including a load and a motor, applies, to a position command, a damping filter determined based on a model parameter corresponding to a model of the device, and outputs a filtered position command to which the damping filter has been applied; a servo controller which gives a torque command to the motor based on the filtered position command; a low-pass filter unit; a parameter estimation unit which estimates the model parameter from the rotational speed and the torque command of the motor which have passed through the low-pass filter unit; and a vibration determination unit which determines presence or absence of vibration in the model.