A pump jack controller is provided that can harness the waste energy generated during the operation of a pump jack when its electrical motor is in an over-speed condition, and convert that waste energy into electrical energy that can be supplied back onto an electrical power grid thus converting the pump jack into a micro electric power generator.

In an electric power steering device assisted by a brushless motor, an induced voltage from a brushless motor is detected when a main power supply is off. The motor is determined to be in a high rpm state when the induced voltage is in a first transient state from a voltagea high rpm detection threshold Th1 to a voltageTh1, thereby setting an intermittent excitation cycle of a revolution angle sensor connected to the motor to a short cycle. The motor is determined to be in a low rpm state when the induced voltage becomes a voltagea high rpm detection threshold Th2 after a wait period corresponding to an electrical angle between peaks or valleys of an output voltage has elapsed in a second transient state from a voltageTh1 to a voltageTh2, thereby setting the cycle to a long cycle.

A motor driving apparatus which drives a motor including a plurality of winding portions corresponding to a plurality of phases, respectively, includes a motor including a plurality of winding portions corresponding to a plurality of phases, respectively, a first inverter including a plurality of first switching elements and electrically connected to a first end of each of the winding portions, a second inverter including a plurality of second switching elements and electrically connected to a second end of each of the winding portions, a plurality of third switching elements including first ends electrically connected to the second ends of the plurality of winding portions, respectively, and second ends electrically connected to each other, and a controller.

In a hybrid vehicle, noise occurrence caused in a rectangular wave control of a motor is restricted when a motor running mode is selected with a converter boosting limit applied. A motor controller for a hybrid vehicle mounted with an internal combustion engine and a motor as power sources is provided. The motor controller includes a converter capable of boosting a voltage supplied from a power supply device; an inverter which converts an output voltage of the converter to an AC voltage and applies the AC voltage to the motor; and a control unit which controls the inverter to drive the motor by switching between two or more control modes. When a running mode to drive the vehicle by a motor power alone is selected with a boost limit applied to the output voltage of the converter and when the motor is driven in a rectangular wave control mode or an overmodulation PWM control mode, the control unit raises the output voltage of the converter higher than a boost limit value and controls the inverter such that the control mode is switched to drive the motor in a sinusoidal PWM control mode.

An electric or hybrid electric-endothermic traction system, comprises an electric machine, an inverter, a battery, and a switching device configured to switch between a low-speed configuration, wherein the stator windings assume a first electric configuration, and a high-speed configuration, wherein the stator windings assume a second electric configuration, wherein the first electric configuration determines a voltage induced by the rotation of the rotor that, on reaching a pre-determined threshold value of the angular velocity of the rotor, exceeds a supply voltage of the battery pack, while the second electric configuration of the stator windings determines a voltage induced by the rotation of the rotor that is lower than the voltage of the battery for any angular velocity within a field of use of the machine. The switching device switches from the low-speed to the high-speed configuration when the rotor reaches a switching speed lower than or equal to the threshold value.

Hybrid motor drive circuits configured to drive a motor are provided herein. A hybrid motor drive circuit includes an inverter coupled to the motor and configured to drive the motor when a motor commanded frequency is not within a predetermined range of line input power frequencies. The hybrid motor drive circuit also includes a first switch device configured to couple line input power to an output of the inverter when the motor commanded frequency is within the predetermined range of line input power frequencies.

An electrical gear configured to supply electrical drive power to a machinery to be rotated at high speed, such as a subsea motor/pump or a subsea motor/compressor assembly, the electrical gear including a high input voltage AC-motor having a low pole number, the AC-motor drivingly connected to a medium output voltage AC-generator having inverted design, wherein in the AC-generator the field windings are supported on a rotor which is journalled for rotation inside an outer stator carrying a high number of magnet poles, the AC-motor is configured to run on high voltage alternating current at a first frequency, and the AC-generator is configured to deliver medium voltage alternating current at a second frequency, higher than said first frequency, to an AC-motor to be energized having a low pole number.

Hybrid motor drive circuits configured to drive a motor are provided herein. A hybrid motor drive circuit includes an inverter coupled to the motor and configured to drive the motor when a motor commanded frequency is not within a predetermined range of line input power frequencies. The hybrid motor drive circuit also includes a first switch device configured to couple line input power to an output of the inverter when the motor commanded frequency is within the predetermined range of line input power frequencies.

A driving system of a driving motor is proposed. The system includes: a stator having slots at which coils are wound; a first inverter connected to first ends of the coils of the stator; a second inverter connected to second ends of the coils of the stator; and a stage switch circuit configured to control an electrical connection between the second ends of the coils of the stator and the second inverter. In particular, the coils include a first coil set connected to an output terminal of the first inverter, and a second coil set connected to an input terminal of the second inverter. Currents having the same phase or currents having different AC phases are applied to the first coil set and the second coil set wound at the slots by controlling on and off of the stage switch circuit.