An inverter for driving a motor that has a switchable connection of windings and drives a load element having a periodically varying load torque is provided. The inverter is controlled so that an output torque of the motor follows the periodic variation of the load torque. The inverter is controlled so that a current flowing through the motor is zero during a period including a minimum torque phase at which the load torque is at or near a minimum value. The connection is switched while the current flowing through the motor is zero. It is possible to switch the connection of the windings while the motor is rotating, and avoid an increase in apparatus size.

A method operates a steering device which comprises at least one electric motor that can be operated with an increased torque lying between a nominal torque of the electric motor and a maximum torque of the electric motor over an entire basic setting range. In at least one operating state, a threshold torque of the electric motor is at least temporarily limited to a reduced torque, in particular in comparison to the maximum torque, at least depending on at least one temperature characteristic variable.

Apparatus, systems, and processes control an electric motor to drive a hoop onto a wooden barrel, among other purposes. A controller may be connected to the electric motor and configured to receive user input data and generate one or more control signals for the electric motor that correspond to a torque generation of the electric motor and/or a rotation speed of the electric motor. A barrel hoop driver may comprise the controller and electric motor, where the electric motor drives a press member for driving hoops onto wooden barrels.

A fuel cell system mounted on a vehicle includes a fuel cell, a fuel cell control unit having a normal mode and a meeting mode in which quietness is given a higher priority than in the normal mode, as a control mode of the fuel cell, a determining unit configured to determine whether there is a request to switch the control mode to the meeting mode, and a mode switch unit configured to switch the control mode to the meeting mode when the determining unit determines that there is a request to switch the control mode to the meeting mode.

The invention relates to a method and system for calibrating a control device, in particular an inverter control device, of an electric motor, comprising operating the electric motor as part of a force flow; performing a force measurement by means of piezo elements which are arranged in the force flow in such a way that the force flow is applied, in particular exclusively, to the piezo elements; and adapting a control characteristic the control device on the basis of at least one force component derived from the force measurement, in particular a change in the at least one force component and/or at least one torque component derived from the force measurement, in particular a change in the torque component.

The disclosure relates to a motor parameter measuring device and method. According to the disclosure, a motor parameter measuring device comprises a torque receiver receiving a motor torque of a motor rotated by an external force, a motor constant calculator calculating a motor constant based on the motor torque, and a parameter calculator controlling an inverter connected with the motor to form a closed circuit and calculating a parameter of the motor based on a current generated by the rotating motor in the closed circuit.

A control method of an electric machine is described, including a first step of detecting the angular position of a rotor of the electric machine; a second step of detecting the values of the alternate current next to at least two phases of the input current to the electric machine; a third step of detecting the values of voltage and direct current supplied as input to the inverter by the electric supply means; a fourth step of estimating the torque supplied by the electric machine performed by processing data detected in the first and second step; a fifth step of computing the torque supplied by the electric machine performed by processing data detected in the third and first step; a sixth step of comparing the value of the computed torque and the value of the estimated torque; a control system and a motor comprising such system are further described.

A method of controlling operation of an electric machine includes: determining a voltage-based torque limit based on a voltage constraint of a direct current (DC) bus supplying power to an inverter for powering the electric machine; determining a motor current-based torque limit based on a motor current limit; determining a final torque limit based on the voltage-based torque limit and the motor current-based torque limit; determining a limited command torque based on a torque command and the final torque limit; determining an initial current command corresponding to the inverter satisfying a regenerative current limit of the DC bus; and calculating a final current command based on, at least, the limited command torque and the initial current command. The method includes the final current command exceeding the initial current command to cause the electric machine to produce a torque corresponding to the limited torque command.

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.

Methods, systems, and devices for electric machine torque adjustment based on waveform integer multiples are disclosed herein. One electric machine controller arranged to direct pulsed operation of an electric machine includes utilizing a pulse controller that calculates an average torque based upon a time period that corresponds with an integer multiple of a waveform cycle of a pulse waveform.