A control circuit of an electric motor includes a filtering device in order to filter high frequencies likely to produce perturbing electromagnetic radiation when the electric motor is driven. To this end, the filtering device includes one or more filtering capacitors branched off from a power bridge driving the electric motor, wherein at least a proportion of the filtering capacitors is of a polymer-hybrid type in order to improve dynamic performance of the filtering device and to reduce its size. A motorized-fan unit for motor vehicles including such a control circuit is also disclosed.

In a resonance suppression control device that controls suppression of vibrations in a resonance frequency in each vibration mode of a control target having a plurality of vibration modes, a configuration that is simple, and can suppress vibrations in a resonance frequency in the plurality of vibration modes is provided. A control device is a resonance suppression control device that controls suppression of vibrations in a resonance frequency in each vibration mode of a control target having a plurality of vibration modes. The control device includes a plurality of feedback loops that provide negative feedback of output of the control target corresponding to the plurality of vibration modes to an input side. The plurality of feedback loops respectively include band-pass filters that extract one or more vibration modes from the plurality of vibration modes, phase compensators, and amplitude adjusters. The band-pass filters and the phase compensators function as differentiators.

In a resonance suppression control device that controls suppression of vibrations in a resonance frequency in each vibration mode of a control target having a plurality of vibration modes, a configuration that is simple, and can suppress vibrations in a resonance frequency in the plurality of vibration modes is provided. A control device is a resonance suppression control device that controls suppression of vibrations in a resonance frequency in each vibration mode of a control target having a plurality of vibration modes. The control device includes a plurality of feedback loops that provide negative feedback of output of the control target corresponding to the plurality of vibration modes to an input side. The plurality of feedback loops respectively include band-pass filters that extract one or more vibration modes from the plurality of vibration modes, phase compensators, and amplitude adjusters. The band-pass filters and the phase compensators function as differentiators.

A method for operating a motor vehicle having at least one electric machine, which is electrically coupled across a pulse inverter to a DC distribution bus of a high-voltage onboard network of the motor vehicle, includes, by means of a compensation unit electrically coupled to the DC distribution bus, feeding an electric compensation voltage to the DC distribution bus such that ripple of the electric DC voltage present in the DC distribution bus which is caused by the pulse inverter is at least partly compensated.

This application provides a permanent-magnet synchronous machine control method and device, and a permanent-magnet synchronous machine control system. The method includes: obtaining a d-axis current i.sub.d and a q-axis current i.sub.q in a permanent-magnet synchronous machine control loop at a current moment; obtaining a fifth-order harmonic current i.sub.d5th and a seventh-order harmonic current i.sub.d7th in the d-axis current i.sub.d in the permanent-magnet synchronous machine control loop at the current moment, and a fifth-order harmonic current i.sub.q5th and a seventh-order harmonic current i.sub.q7th in the q-axis current i.sub.q in the permanent-magnet synchronous machine loop at the current moment; determining a d-axis current i.sub.d.sup.k+1 at a next moment in each switch state; determining a q-axis current i.sub.q.sup.k+1 at the next moment in each switch state based on the first current i.sub.d.sup.k, the second current i.sub.q.sup.k, and the second voltage in each switch state; and determining a control policy of the permanent-magnet synchronous machine.

A motor control system with adjustable voltage harmonic and a method for correcting the motor control system is disclosed. Based on the input modulation order, the motor control system drives and controls a motor. The motor control system includes: a control order selection unit to generate a control order based on the modulation order, a modulation signal control unit used to generate a pulse output duty ratio modulation signal, a harmonic voltage weight selection unit used to select the weight value of the harmonic wave, a pulse modulation part to generate a control signal based on the modulation signal indicating the pulse output duty ratio, the weight value of the harmonic wave, and the pulse modulation carrier frequency signal. Based on the control signal, the inverter circuit adds the harmonic voltage into the motor-driving voltage to drive the motor, so as to reduce the noise or vibration of the motor.

A motor control system with adjustable voltage harmonic and a method for correcting the motor control system is disclosed. Based on the input modulation order, the motor control system drives and controls a motor. The motor control system includes: a control order selection unit to generate a control order based on the modulation order, a modulation signal control unit used to generate a pulse output duty ratio modulation signal, a harmonic voltage weight selection unit used to select the weight value of the harmonic wave, a pulse modulation part to generate a control signal based on the modulation signal indicating the pulse output duty ratio, the weight value of the harmonic wave, and the pulse modulation carrier frequency signal. Based on the control signal, the inverter circuit adds the harmonic voltage into the motor-driving voltage to drive the motor, so as to reduce the noise or vibration of the motor.

A control device includes: a prediction unit configured to predict the harmonic current at each of prediction points comprised in a predetermined prediction target period after current time, based on control information of the motor in at least a next carrier cycle of the inverter, and a command value determination unit configured to output, to the active filter unit, a current command value for generating a compensation current having a polarity opposite to a polarity of a harmonic current at a prediction point, at a timing corresponding to the prediction point comprised in the next carrier cycle in the prediction target period, based on a prediction result of the prediction unit. Each of the prediction points is provided at a predetermined time interval since start time of the prediction target period. The time interval is longer as the next carrier cycle is longer.

A common mode line-to-ground filter is disclosed which includes but is not limited to a resistor, capacitor and a ground. The common mode line to ground filter is connected on a high side of a step-up transformer. A low side of the step-up transformer is connected to a variable frequency drive that provides a semi-sinusoidal voltage waveform. The common mode line to ground filter generates a filtered sinusoidal waveform from the output of the step-up transformer. The filtered sinusoidal voltage waveform is supplied via an electrical cable to an electrically submersible pump deployed downhole.

A planar drive system comprises a stator and a rotor. The stator comprises a plurality of energizable stator conductors. The rotor comprises a magnet device having at least one rotor magnet. A magnetic interaction can be produced between energized stator conductors of the stator and the magnet device in order to drive the rotor. The stator is configured to carry out energization of the stator conductors so that an alternating magnetic field can be generated via the energized stator conductors. The rotor comprises at least one rotor coil in which an alternating voltage can be induced due to the alternating magnetic field. The planar drive system is configured to transmit data from the rotor to the stator, and the rotor is configured to temporarily load the at least one rotor coil to temporarily cause increased current consumption of the energized stator conductors of the stator.