Abstract: An electric motor comprises: a stator having slots; and a rotor including a stack of rotor laminations, the rotor comprising: a first substack of the rotor laminations, wherein the rotor laminations in the first substack include first rivet holes and first magnet holes with first permanent magnets; and a second substack of the rotor laminations, wherein the rotor laminations in the second substack include second rivet holes and second magnet holes with second permanent magnets, and wherein an orientation of the first sub stack and the second substack relative to each other provides the rotor with a skew.

Abstract: An electric motor comprises: a rotor having poles equaling a first number; and a stator having slots equaling a second number, the stator having stator windings formed by conductors wound in a wave pattern around the stator, wherein a third number of the conductors are located in each of the slots, wherein the conductors form three balanced parallel paths through the slots, each of the conductors in the three balanced parallel paths undergoing a same number of pitch turns, each of the pitch turns being either a standard pitch turn or a nonstandard pitch turn, the standard pitch turn involving wrapping around slots equaling the second number divided by the first number, the nonstandard pitch turn involving wrapping around more or fewer slots than the standard pitch turn, wherein each of the three balanced parallel paths forms a repeating pattern throughout the slots.

Abstract: An electric motor comprises: a rotor having poles equaling a first number; and a stator having slots equaling a second number, the stator having stator windings formed by conductors wound in a wave pattern around the stator, wherein a third number of the conductors are located in each of the slots, wherein the conductors form three balanced parallel paths through the slots, each of the conductors in the three balanced parallel paths undergoing a same number of pitch turns, each of the pitch turns being either a standard pitch turn or a nonstandard pitch turn, the standard pitch turn involving wrapping around slots equaling the second number divided by the first number, the nonstandard pitch turn involving wrapping around more or fewer slots than the standard pitch turn, wherein each of the three balanced parallel paths forms a repeating pattern throughout the slots.

Abstract: Controlling a multiphase electric motor by controlling the transmission of power to a first set of phases of a multiphase electric motor in accordance with a first operating configuration; detecting the presence of a shorted phase in the first set of phases while the first set of phases are being operated in accordance with the first operating configuration; and, responsive to detection of the shorted phase, adjusting control of the transmission of power to the multiphase electric motor such that power is transmitted to a second set of phases in accordance with a second operating configuration.

Abstract: A multiphase electric motor for a down-hole electrical submersible pump having a rotor having a first set of rotor voids filled or partially filled with permanent magnetic material. The electric motor having a stator with three or more stator slots, three or more stator teeth and three or more coils. Individual ones of the three or more coils are wound about at least one of the individual ones of the three or more stator teeth, and positioned such that adjacent coils are non-overlapping or partially overlapping to form a fractional slot per pole per phase winding. The electric motor having a power supply configured to provide power to the three or more phase windings formed by series or parallel combination of the three or more coils and a controller configured to control transmission of power through the three or more windings.

Abstract: Controlling a multiphase electric motor by controlling the transmission of power to a first set of phases of a multiphase electric motor in accordance with a first operating configuration; detecting the presence of a shorted phase in the first set of phases while the first set of phases are being operated in accordance with the first operating configuration; and, responsive to detection of the shorted phase, adjusting control of the transmission of power to the multiphase electric motor such that power is transmitted to a second set of phases in accordance with a second operating configuration.

Abstract: A method for driving a brushless direct current (DC) motor is provided. The brushless DC motor has a first phase that is coupled between a first terminal and a common node, a second phase that is coupled between a second terminal and the common node, and a third phase that is coupled between a third terminal and the common node. The first and second phases are coupled to a first supply rail and a second supply rail, respectively, such that the brushless DC motor is in a first commutation state. The first phase is then decoupled from the first supply rail so as to allow first terminal to float during a window period. A first voltage difference between the first terminal and the second terminal is compared to a second voltage difference between the third terminal and the second terminal during the window period, and the brushless DC motor is commuted to a second commutation state if the first voltage difference is approximately equal to the second voltage difference.

Abstract: A system for determining an initial position of a rotor (9) of a PMSM motor includes a motor controller (2) coupled to a plurality of phase windings of the motor by means of an actuation circuit (3). A processor (12) and an interface circuit (14) are coupled to the processor and the phase windings. The processor determines if the rotor speed is zero, and if so causes the actuation circuit to sequentially apply voltage signals (Vab, Vba, Vac, Vca, Vbc, and Vcb) to the phase windings to produce corresponding phase winding current signals (Iab, Icb, Ica, Iba, Ibc, Iac) in the various phase windings. The phase winding current signals are sensed and digitized. The processor then determines a position of a magnetic flux path associated with the rotor by computing the initial position of the rotor from one of the digitized phase winding current signals associated with the predetermined magnetic flux path.

Abstract: A system for determining an initial position of a rotor (9) of a PMSM motor includes a motor controller (2) coupled to a plurality of phase windings of the motor by means of an actuation circuit (3). A processor (12) and an interface circuit (14) are coupled to the processor and the phase windings. The processor determines if the rotor speed is zero, and if so causes the actuation circuit to sequentially apply voltage signals (Vab, Vba, Vac, Vca, Vbc, and Vcb) to the phase windings to produce corresponding phase winding current signals (Iab, Icb, Ica, Iba, Ibc, Iac) in the various phase windings. The phase winding current signals are sensed and digitized. The processor then determines a position of a magnetic flux path associated with the rotor by computing the initial position of the rotor from one of the digitized phase winding current signals associated with the predetermined magnetic flux path.

Abstract: A method for driving a brushless direct current (DC) motor is provided. The brushless DC motor has a first phase that is coupled between a first terminal and a common node, a second phase that is coupled between a second terminal and the common node, and a third phase that is coupled between a third terminal and the common node. The first and second phases are coupled to a first supply rail and a second supply rail, respectively, such that the brushless DC motor is in a first commutation state. The first phase is then decoupled from the first supply rail so as to allow first terminal to float during a window period. A first voltage difference between the first terminal and the second terminal is compared to a second voltage difference between the third terminal and the second terminal during the window period, and the brushless DC motor is commuted to a second commutation state if the first voltage difference is approximately equal to the second voltage difference.