2303results about "Polyphase induction motor starter" patented technology

A controllable motor includes a rotor. A first stator winding set is operable, upon being energized, to generate and apply a first torque to the rotor. A second stator winding set independent of the first stator winding set is operable, upon being energized, to generate and apply a second torque to the rotor. A motor control is coupled to the first and second stator winding sets. The motor control is operable to selectively energize one of the first or second stator winding sets to thereby generate and apply one of the first or second torques to the rotor, and simultaneously energize both the first and second stator winding sets to thereby generate and apply a third torque greater than the first or the second torque.

The invention is directed to controlling an electric motor by means of a frequency converter. The frequency converter can be connected to one of several different mains voltages. According to the present invention, the maximum output power of the frequency converter, is limited when the actual mains voltage is lower than the maximum nominal mains voltage, for which the frequency converter is designed, and during the limitation the frequency converter controls the speed of the motor within a power range up to a limited maximum output power. This gives a genuine multi-voltage unit, which can be connected to a wide range of mains voltages.

The present invention is a power supply (10) that starts a load (20) with a heavy start-up power draw from a power grid (12) and then switches the load to a generator (22) for lower power draw operation thereby avoiding the need for a large capacity generator capable of initial start-up of the load (20). The power supply comprises a conductor (15) for connecting to a power grid, an electrical power generation device (30), an electrical power using device or load (20) and a switching mechanism (40) for 1) isolating the power grid (12) from the power generation device (30), 2) connecting the power grid conductor (15) to the electrical power using device (20) for the initial start-up of the power using device (20), and 3) connecting the power generation device (30) to the power using device (20) after initial start-up. In addition the power supply (10) can also serve as a backup source of power for multiple circuits whose total startup load exceeds the total output of the generator (30) during periods of grid power failure by selectively turning off interruptible circuit load (20) during the startup of other circuits (16) or allowing intermittent circuit loads (20) to complete their cycle and return to an off state prior to the start-up of other circuits (16).

A variable frequency power system with a power source having a rotating output and a speed control to regulate rotational speed of the rotating output. A generator coupled to and driven by the rotating output of the power source, whereby the speed control of the power source directly controls output power frequency of the generator due to control of rotational frequency of the rotating output. A voltage regulator connected between the generator and the motor regulates output voltage from the generator to the electrical motor load. A system controller controls output power frequency of the generator. The system controller interfaces with the speed control of the power source and configured to monitor generator output and operational conditions of the electrical motor load. The system controller adjusts the speed control based on generator output and operational conditions of the electrical motor load.

A method of starting a permanent magnet machine. A machine stator voltage in a stationary reference frame is sensed. An initial speed of a rotor of the machine is estimated based on the sensed voltage, and state variables of control algorithms are initialized based on the estimated initial speed. This method can provide smooth startup and / or restart at any speed.

A traction control system for controlling an electric traction motor drivingly coupled to a wheel of a tractive vehicle. The traction control system includes means for determining speed of the wheel, means for determining tractive effort of the wheel and a control circuitry for controlling drive signals to the motor based upon the wheel speed and tractive effort.

A method for controlling a device including a plurality of switching devices operated in accordance with a pulse width modulation technique includes receiving a reference voltage signal associated with a first pair of the switching devices. A switching signal is generated. The first pair of switching devices are controlled based on the reference voltage signal and the switching signal in accordance with the pulse width modulation technique. A frequency of the switching signal is varied based on the value of the reference voltage signal.

A motor controller includes: a driver stage operable to provide voltage and current to a plurality of induction motors over a single power bus; and a control unit operable to monitor the current drawn from the driver stage and cause one or more of the induction motors to operate in a regenerative mode to supply current to at least one other of the induction motors when the current drawn from the driver stage exceeds a threshold.

A motor starting device employs a relay to connect and disconnect an auxiliary start capacitor in parallel with the existing start capacitor of a single-phase split-capacitor induction motor. The relay is normally closed and in the initial state connects the auxiliary start capacitor in parallel with the existing start capacitor. After a source of alternating current voltage is connected to the motor, a control circuit energizes the relay to disconnect the auxiliary start capacitor after a delay time. When the source of alternating current voltage is disconnected from the motor, a relay protection circuit maintains the relay switch open until the charge has dissipated from both the existing start capacitor and the auxiliary start capacitor.

Connected to a 3-phase linear motor of a submersible oil pump of a crude oil production system, a linear motor automatic control circuit assembly is disclosed to include a linear motor power supply circuit, a CPU, an insulated gate bipolar transistor driving circuit, a current detection circuit, a temperature sensor, a fluid depth sensor, a function setting and status display circuit, and a circuit assembly power supply circuit for controlling the operation speed of the linear motor subject to the submergence depth of the linear motor in the oil well.

A vehicle electric drive system and a hybrid engine-motor type vehicle drive system realizing simplification and miniaturization of electric parts and, moreover, reduction in cost while maintaining performances can be provided. A part 1 of wheels is driven by an engine. The wheels are driven by a motor as necessary. The motor, a generator, and an accessory battery are connected to each other via a voltage step-up / step-down device. The voltage step-up / step-down device has a function of stepping up power of the battery and supplying the stepping up power to the motor, and a function of stepped down power of the generator and supplying the stepped down power to the battery and the accessories.

A hybrid air-gap / solid-state device protection device (PD) for use in an electrical power distribution system includes an air-gap disconnect unit connected in series with a solid-state device, a sense and drive circuit, and a microcontroller. Upon the sense and drive circuit detecting an impending fault or exceedingly high and unacceptable overvoltage condition in the PD's load circuit, the sense and drive circuit generates a gating signal that quickly switches the solid-state device OFF. Meanwhile, the microcontroller generates a disconnect pulse for the air-gap disconnect unit, which responds by forming an air gap in the load circuit. Together, the switched-OFF solid-state device and air gap protect the load and associated load circuit from being damaged. They also serve to electrically and physically isolate the source of the fault or overload condition from the remainder of the electrical power distribution system.

In some embodiments, an apparatus and a system, as well as a method and an article, may include receiving shunt current in one or more conductors according to a sensed component of power distributed by the conductors through one or more transformers coupled to the conductors and determined by an inductance associated with the transformers and a capacitance associated with the conductors.

A hybrid electric vehicle having an energy generation system, an energy storage system and at least one, and preferable two or more, traction drive units includes a controller for controlling operation of vehicle systems. The controller may adaptively control traction by one or more traction drive units to better propel the vehicle. The controller may, for example, prevent unnecessary wheel slip, allow a traction profile to match a desired profile, and may be used to assist in turning of the vehicle. A method of adaptive control is also provided.

A vehicle electric drive system and a hybrid engine-motor type vehicle drive system realizing simplification and miniaturization of electric parts and, moreover, reduction in cost while maintaining performances can be provided. A part 1 of wheels is driven by an engine. The wheels are driven by a motor as necessary. The motor, a generator, and an accessory battery are connected to each other via a voltage step-up / step-down device. The voltage step-up / step-down device has a function of stepping up power of the battery and supplying the stepping up power to the motor, and a function of stepped down power of the generator and supplying the stepped down power to the battery and the accessories.

A controller for controlling a wiper unit including a wiper and an intermittent wipe cycle setting device for setting an intermittent wipe cycle of the wiper. The cycle setting device is set at a plurality of positions respectively corresponding to different intermittent wipe cycles. Further, the cycle setting device has a resistance value, which changes in accordance with each of the positions, and generates an output signal, which is in accordance with the change in the resistance value. The controller computes position information of the intermittent wipe cycle setting device from the output signal by using a learned value. The computer adjusts the learned value in accordance with the computation result of the position information to correct the position information. Accordingly, resistance value variances of the intermittent wipe cycle setting device are automatically corrected.