This document describes stepper motor drive systems. The stepper motor drive systems can be used in many different applications including, for example, to drive a stepper motor of an occluder device in association with a heart-lung machine.

A control system for a switched reluctance machine includes a capacitor and an inverter connected to the capacitor, wherein the inverter generates current signals and a ripple current returned to the capacitor. A switched reluctance machine (SRM) receives the current signals and generates a position signal. A controller receives the ripple current, current signal values of the current signals, and the position signal and generates desired reference current waveforms received by the inverter to adjust the current signals received by the SRM.

This document describes stepper motor drive systems. The stepper motor drive systems can be used in many different applications including, for example, to drive a stepper motor of an occluder device in association with a heart-lung machine.

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.

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 control system for a switched reluctance machine includes a capacitor and an inverter connected to the capacitor, wherein the inverter generates current signals and a ripple current returned to the capacitor. A switched reluctance machine (SRM) receives the current signals and generates a position signal. A controller receives the ripple current, current signal values of the current signals, and the position signal and generates desired reference current waveforms received by the inverter to adjust the current signals received by the SRM.

A device may receive a current measurement of a motor identifying a plurality of component currents associated with a plurality of phases. The device may determine a position estimate for the motor based on the plurality of component currents associated with the plurality of phases. The device may control the motor based on the plurality of component currents.

A controller for a switched reluctance motor is provided. The switched reluctance motor includes a rotor, a stator, and a coil wound on the stator. The switched reluctance motor is mounted on a vehicle as a drive source for propelling the vehicle. The controller includes an electronic control unit. The electronic control unit is configured to execute first control for exciting the coil at a first current value in a first exciting range. The electronic control unit is configured to, when the electronic control unit determines that the vehicle is not able to start moving even when the electronic control unit executes the first control, execute second control for exciting the coil at a second current value larger than the first current value in a second exciting range narrower than the first exciting range.

A device may receive a current measurement of a motor identifying a plurality of component currents associated with a plurality of phases. The device may determine a position estimate for the motor based on the plurality of component currents associated with the plurality of phases. The device may control the motor based on the plurality of component currents.

A starter includes a three-phase switched reluctance electric motor including a rotor and a stator, a pinion gear, a power inverter that is connected to the stator, and a rotational position sensor. The rotor includes a quantity of rotor poles that is between 6 and 16, and the stator includes a quantity of stator poles that is between 8 and 24. An outer diameter of the electric motor is less than 85 mm. An active length of the motor is less than 50 mm. An airgap distance between the rotor and the stator is between 0.1 mm and 0.5 mm. A ratio between a rotor pole arc and a stator pole arc is at least 1.0:1. A ratio between a stator diameter and a rotor diameter is at least 2.0:1, and a ratio between a stator pole height and a rotor pole height is at least 2.5:1.