A three-phase switched reluctance machine has a rotor, a first stator and a second stator. The rotor, first stator and second stator are coaxially and concentrically disposed. The rotor and both the first stator and second stator have corresponding poles. Only one of the stators has coils wound about its poles, while the other stator does not have any coils. A defined relationship between the number of rotor poles, the number of stator poles on the first stator and the number of stator poles on the second stator may improve the torque quality of the switched reluctance machine.

An electric motor may comprise a rotor and a stator comprising rotor and stator teeth, respectively. A non-uniform angular spacing or grouping of rotor teeth may facilitate desired rotational speeds of the rotor. In an embodiment, such non-uniform angular spacing may be such that for at least a subset of the rotor teeth comprising a first, second, and third rotor tooth, an angular spacing between the first and the second rotor teeth is at least twice an angular spacing between the second and the third rotor teeth.

A controller of a rotating electric machine includes a current detector detecting a voltage of each of shunt resistors in at least two phases from among the shunt resistors in three phases during an electric current flowing period in which the shunt resistors in the at least two phases have an electric current flowing therein; and a signal generator setting a switching mode of each of switches forming an inverter for controlling an estimated angular velocity to an instruction angular velocity based on the detected voltage. The signal generator sets a switching mode to flow the electric current in the shunt resistors in the at least two phases during at least part of one half of a modulation cycle of control of the estimated angular velocity.

A controller of a rotating electric machine includes a current detector detecting a voltage of each of shunt resistors in at least two phases from among the shunt resistors in three phases during an electric current flowing period in which the shunt resistors in the at least two phases have an electric current flowing therein; and a signal generator setting a switching mode of each of switches forming an inverter for controlling an estimated angular velocity to an instruction angular velocity based on the detected voltage. The signal generator sets a switching mode to flow the electric current in the shunt resistors in the at least two phases during at least part of one half of a modulation cycle of control of the estimated angular velocity.

A motor control device including a PWM generator generating a PWM generator generating a PWM signal to be outputted to a drive circuit that energizes a winding of a switched reluctance motor; a rectangular wave generator outputting a rectangular wave signal of 1 pulse or more to the drive circuit in 1 drive period of each phase based on a rotational position of the motor; and a drive signal switcher executing switching so that a PWM drive by the PWM signal is performed when a rotational speed of the motor is equal to or less than a threshold value and a rectangular wave drive by the rectangular wave signal is performed when the rotational speed of the motor is greater than the threshold value. The PWM generator synchronizes a timing to start generation of a carrier of the PWM signal with rising of the rectangular wave signal.

A motor control device including a PWM generator generating a PWM generator generating a PWM signal to be outputted to a drive circuit that energizes a winding of a switched reluctance motor; a rectangular wave generator outputting a rectangular wave signal of 1 pulse or more to the drive circuit in 1 drive period of each phase based on a rotational position of the motor; and a drive signal switcher executing switching so that a PWM drive by the PWM signal is performed when a rotational speed of the motor is equal to or less than a threshold value and a rectangular wave drive by the rectangular wave signal is performed when the rotational speed of the motor is greater than the threshold value. The PWM generator synchronizes a timing to start generation of a carrier of the PWM signal with rising of the rectangular wave signal.

The drive system includes a motor, a power converter, and a controller. The motor is a reluctance motor that rotates in response to feeding of electric power. The power converter includes multiple switching elements and is connected directly to the motor. The power converter converts electric power fed from a power source into electric power to be fed to the motor and feeds the converted electric power to the motor. The controller controls the switching elements included in the power converter.

The drive system includes a motor, a power converter, and a controller. The motor is a reluctance motor that rotates in response to feeding of electric power. The power converter includes multiple switching elements and is connected directly to the motor. The power converter converts electric power fed from a power source into electric power to be fed to the motor and feeds the converted electric power to the motor. The controller controls the switching elements included in the power converter.

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.

An electrical inverter may include a plurality of phase modules to provide a plurality of phase outputs. Two or more of the plurality of phase modules may share a common insulated-gate bipolar transistor.