A haptic system includes a haptic engine in which a reluctance motor is driven by a driver controller operated in conjunction with an impedance-estimator that uses amplitude-modulated calibration signals. An enveloped-calibration signal is superimposed on a haptic-drive signal to quickly, and accurately, estimate the driving coil's impedance, while minimizing power penalty.

A haptic system includes a haptic engine in which a reluctance motor is driven by a driver controller operated in conjunction with an impedance-estimator that uses amplitude-modulated calibration signals. An enveloped-calibration signal is superimposed on a haptic-drive signal to quickly, and accurately, estimate the driving coil's impedance, while minimizing power penalty.

A motor system comprises a device having a plurality of conductors coupled to a plurality of isolated connection bars, wherein the plurality of conductors is divided symmetrically into a plurality of conductor groups, and all conductors in a conductor group are connected to a connection bar, a first power converter group connected between a first power source and a first conductor group, a second power converter group connected between a second power source and a second conductor group, wherein the first group of conductors and the second group of conductors are configured such that a charge balance between the first power source and a second power source is achieved and a rotor magnetically coupled to a stator.

A motor system comprises a device having a plurality of conductors coupled to a plurality of isolated connection bars, wherein the plurality of conductors is divided symmetrically into a plurality of conductor groups, and all conductors in a conductor group are connected to a connection bar, a first power converter group connected between a first power source and a first conductor group, a second power converter group connected between a second power source and a second conductor group, wherein the first group of conductors and the second group of conductors are configured such that a charge balance between the first power source and a second power source is achieved and a rotor magnetically coupled to a stator.

The disclosure relates to a method for determining an incorrect operating state of an electrical machine with the aid of an electronic circuit having at least one comparator. The electrical machine is controlled with a pulse width modulation signal. The pulse width modulation signal is demodulated. A first signal, which represents the demodulated pulse width modulation signal, is compared with a second signal. The second signal represents a rotational speed or a rotational angle of the electrical machine and/or a current intensity of the electrical machine. This comparison is carried out with the aid of the at least one comparator. An error signal is generated based on the comparison in order to determine the incorrect operating state of the electrical machine.

A switched reluctance motor for an electric vehicle. The switched reluctance motor includes an inverter with switchable windings to control the inductance of the motor. The motor also includes a high speed and low speed mode corresponding to the inductance of the motor. The inverter may include parallel switches, selectively running current to the windings in order to control the inductance.

A switched reluctance motor for an electric vehicle. The switched reluctance motor includes an inverter with switchable windings to control the inductance of the motor. The motor also includes a high speed and low speed mode corresponding to the inductance of the motor. The inverter may include parallel switches, selectively running current to the windings in order to control the inductance.

Apparatus and methods are provided for operating an electric motor, comprising selectively energising the coils of a stator having a plurality of stator teeth, each stator tooth having a said coil mounted thereon. The stator coils of a subset of the stator teeth are energised during a given time period to attract a corresponding rotor tooth into alignment with each of the stator teeth in the subset over the given time period. The stator coil of at least one stator tooth in the subset is energised during a portion of the given time period before the at least one stator tooth overlaps the corresponding rotor tooth.

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 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.