2307results about "Polyphase induction motor starter" patented technology

A permanent magnet DC brushless motor control assembly permits a user to select the permanent magnet DC brushless motor operating characteristics by selecting appropriate control circuits to interface with the motor. The assembly includes a permanent magnet DC brushless motor, a commutator electrically coupled to the motor, and at least one control module electrically coupled to the commutator, to control operating characteristics of the permanent magnet DC brushless motor.

An electrical hand tool machine (1) having a motor switch (2) configured as a button and a current regulator (4) disposed in the current circuit of an electrical motor (3), having a soft-start input (5), in whose branch current a timing capacitor (6) is arranged. A current-direction-dependent element (7) is arranged between the soft-start input (5) and the capacitor (6).

A robot or manipulator including a wireless power supply and a wireless communication device. One or more actuators on the robot tool may be wirelessly powered and wirelessly controlled. The robot tool may have one or more wireless communication members for transmission of data from sensors on the tool. The power supply includes a primary power supply member and secondary power supply member. Tool changes may be carried out automatically by the robot. In other aspects of the invention a method, a control system and a computer program for carrying out the method are described.

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 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 control system for a motor including a rotor comprises a sensorless sensor module that includes a saliency-based estimator module that generates a first rotor position signal based on saliency and a back electromotive force (emf) estimator module that generates a second rotor position signal based on back emf. A selector selects the first rotor position signal for rotor speeds below a first rotor speed and the second rotor position signal for rotor speeds above the first rotor speed. A rotor position sensor senses a position of the rotor and generates a third rotor position signal. A fault detection module senses faults in the rotor position sensor and outputs the third rotor position signal when a fault is not detected and one of the first and second rotor position signals when the fault is detected. An indirect field oriented control (IFOC) system controls the motor based on a selected one of the first, second and third rotor position signals.

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.

Control of an induction motor is carried out to limit damaging arcing stress and mechanical stresses placed on the control contactor assembly and the induction motor resulting from the simultaneous or synchronous breaking and making of contactors employed to connect the windings of the motor to a power supply. Asynchronously connecting the windings to the power supply via the asynchronous or non-simultaneous closing of the contactors of a modular contactor assembly reduces the potentially damaging transient current, the associated torque oscillations, and mechanical stresses. The present invention is particularly applicable to delta motors that are started with its windings in a star or wye configuration followed by the reconnection of the windings in a delta configuration when the motor is at normal running speed.

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.

Systems and apparatus are provided for an inverter system for use in a vehicle having a first energy source and a second energy source. The inverter system comprises an electric motor having a first set of windings and a second set of windings. The inverter system further comprises a first inverter coupled to the first energy source and adapted to drive the electric motor, wherein the first set of windings are coupled to the first inverter. The inverter system also comprises a second inverter coupled to the second energy source and adapted to drive the electric motor, wherein the second set of windings are coupled to the second inverter. A controller is coupled to the first inverter and the second inverter to achieve desired power flow between the first energy source, the second energy source, and the electric motor.

A sump pump control includes a microprocessor that sends a trigger pulse to an alternistor to turn the alternistor on and connect the sump pump to an NC power source. The microprocessor also monitors the power source to find a positive / negative crossover point. The microprocessor adjusts the trigger to apply full power to the pump motor during normal operation and delays the trigger to apply reduced power for a soft start and soft stop. The microprocessor also triggers an alarm in the event of failure of the device, including failure of the alternistor or the microprocessor.

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 rotating machinery includes a first control member for performing rectangular wave control by operating the switching devices of an inverter such that an on-state and an off-state occur once for one cycle period in electrical angle of a motor, a second control member for operating the switching devices on the basis of a magnitude relation between upper and lower limits of a predetermined hysteresis region and an actual current flowing through the motor, and a switching member for, when the actual current deviates from the hysteresis region while the rectangular wave control is undertaken, switching the control to an instantaneous current value control performed by the second control member.

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.

An apparatus for controlling an operation of a reciprocating compressor includes a inductance increasing device connected to a motor of the reciprocating compressor, so that a surge current generated when power is applied to the reciprocating compressor at an initial stage is reduced and thus an initial stroke of the reciprocating compressor is reduced. Accordingly, operational efficiency of the reciprocating compressor is improved.

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.

A power system that provides power between an energy storage device, an external charging-source / load, an onboard electrical power generator, and a vehicle drive shaft. The power system has at least one energy storage device electrically connected across a dc bus, at least one filter capacitor leg having at least one filter capacitor electrically connected across the dc bus, at least one power inverter / converter electrically connected across the dc bus, and at least one multiphase motor / generator having stator windings electrically connected at one end to form a neutral point and electrically connected on the other end to one of the power inverter / converters. A charging-sourcing selection socket is electrically connected to the neutral points and the external charging-source / load. At least one electronics controller is electrically connected to the charging-sourcing selection socket and at least one power inverter / converter. The switch legs in each of the inverter / converters selected by the charging-source / load socket collectively function as a single switch leg. The motor / generators function as an inductor.

A power controller for applying power to an induction motor or similar AC load has a variable drive circuit for staring and switching a portion of the AC input line power. In one mode, the input line power is fed straight through to the load. In another mode, the AC waveform is reshaped to improve the power factor or to boost its RMS value, e.g., for brownout protection. In a further mode the output power can be provided at a different frequency from the input line power. Vector control increases efficiency through power optimization, with sensing of load requirements. Sensing of regeneration pulses at the commencement of a half cycle can be employed for direct sensing of motor speed or load.

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.

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.

There is provided a controller for a motor capable of changing the phase difference between two rotors that can prevent demagnetization of permanent magnets or the rotors. The motor has two rotors each having a permanent magnet and phase difference changing driving means for changing the phase difference between the rotors. The controller has a demagnetization determining means for determining whether or not demagnetization of the permanent magnets of the rotors occurs during operation of the motor, and rotor phase difference controlling means for controlling the phase difference changing driving means to change the phase difference between the rotors from a current phase difference to a phase difference that results in a higher strength of a composite field of the permanent magnets if the result of determination by the demagnetization determining means is positive.