128results about "AC/AC convertors" patented technology

A system and method for power conversion synchronizes multiple phases at a desired phase angle difference. The power conversion involves variable frequency switching, fixed on-time and provides power factor correction. A relative measure of a phase angle difference between two phases permits each phase to be controlled to obtain the desired phase angle difference. The power conversion involves transition mode switching to help reduce switching losses. A phase angle difference detector may be provided for each phase. The various phases may have different inherent frequencies that vary with switching frequency, and are synchronized to an average frequency. Current measures can be taken with a single component, such as a resistor. A maximum frequency control limits period width to avoid high frequency switching. An added switch on time improves input voltage crossover distortion. One or more phases can be deactivated in light load conditions.

Provided are a super-high speed permanent magnet type synchronous motor which causes less loss in a rotor even though it is driven by an inverter adapted to be operated with a fundamental frequency around 1 kHz, and an air compressor. The air compressor having a super-high speed permanent magnet type synchronous motor which is composed of a stator in which armature windings are wound in a plurality of slots formed in a stator core, and a rotor including a shaft made of a conductive magnetic material, a conductive permanent magnet laid around the outer periphery of the shaft, and a reinforcing member made of carbon fibers and laid around the outer periphery of the permanent magnet, wherein a laminated electromagnetic steel sheet is interposed between the shaft and the permanent magnet, and the laminated electromagnetic steel sheet has a high tensile strength higher than 70 kg/mm2.

A self-contained intelligent cascaded synchronous electric motor-generator tandem of cumulative compound excitation comprises at least a synchronous electric motor-generator tandem (namely MG tandem), a storage battery cluster and an autotransformer. Each MG tandem comprises at least a pair of motor and generator having a common stator and a common rotor shaft. The storage battery cluster, which provides a DC power to general loads and motor, serves as a DC power reservoir to be recharged by generator. The autotransformer serves to regulate the AC voltage output from generator via multiple output taps thereon for supplying various AC voltages to different external loads. By integrating all components aforesaid with common magnetic flux interacted mutually, upon being energized by DC power from storage battery cluster, the motor will transfer rotational torque to drive the generator in enhanced synergistic manner.

In an embodiment, a power converter system includes a plurality of variable frequency power converters and a plurality of synchronization circuits. Each variable frequency power converter has a switching frequency. Each synchronization circuit is associated with a respective one of the plurality of variable frequency power converters. A control circuit is coupled to and coordinates the plurality of synchronization circuits. The plurality of synchronization circuits and the control circuit are operable to synchronize the switching frequencies of the variable frequency power converters to each other. Each synchronization circuit is operable to: receive a first input signal indicative of the beginning of a switching period for the associated variable frequency power converter; receive a second input signal indicative of the end of the switching period for the associated variable frequency power converter; generate a first output signal for directing a pulse width modulation of the associated variable frequency power converter; and generate a second output signal for coordinating a phase relationship with another variable frequency power converter in the system.

The invention relates to a method for compensating for a voltage unbalance in an electrical network, which is fed by using an apparatus based on controlling a flux linkage vector or a voltage vector. Concerning the apparatus based on controlling the flux linkage vector, the method comprises the steps of determining a flux linkage reference vector comprising a positive sequence component and a negative sequence component, and controlling the feeding apparatus of the network in such a manner that the flux linkage vector thereof follows the reference vector with predetermined precision. The negative sequence component of the flux linkage reference vector is arranged to compensate for the amplitude and phase unbalance of the voltage in the electrical network to be fed.

The invention provides an axis static state vacuum partition method of an integrated rotary transformer. The axis static state vacuum partition method comprises the following steps of first, using a permanent magnet synchronous motor with a magnetic directly-driving function to serve as an axis driving and transmission component; second, using a sine and cosine magnetic-resistive type rotary transformer to serve as a position detection part of a motor; third, conducting lengthening on the end portion of an inner magnetic rotor of the motor, removing an inner magnetic rotor of the rotary transformer, forming integrated inner magnetism, and enabling the motor and the rotary transformer to share one integrated inner magnetic rotor through the rotor; and fourth, sealing the integrated inner magnetic rotor of the motor and the rotary transformer in a partition sealing sleeve, and using the partition sealing sleeve to limit radial and axial movement of a magnetic body. The integrated rotary transformer achieves a zero-transmission mode, is stable in operation and small in noise, and achieves contact-free zero-leakage sealing transmission.

An exemplary embodiment provides an electrical machine apparatus that includes a rotor coupled to an armature and a stator surrounding the rotor. The stator has a series of coils; the series of coils configured into a first group of coils and a second group of coils, the first group of coils electrically and magnetically isolated from the second group of coils. The electric machine is capable of simultaneously acting as an electric motor and generating electricity as an alternator.

An alternating current motor control system constituted of: a control unit; a cycloconverter functionality; a phase control functionality; and a semiconductor switching unit comprising a plurality of electronically controlled semiconductor switches each associated with a particular winding of a target alternating current motor and each independently responsive to the control unit. In one embodiment the semiconductor switching unit is arranged to connect the windings of the target alternating current motor to a three phase power input in one of a star and a delta configuration responsive to the control unit.

A permanent magnet D.C. electric motor includes a stator housing, permanent magnet structure, and an armature assembly. The armature assembly includes a shaft rotatably mounted in the stator housing, lamination structure, first and second coil windings associated with the lamination structure, a first commutator electrically connected with the first coil windings, and second commutator electrically connected with the second coil windings, each of the first and second commutators being generally cylindrical and having a plurality of commutator segments. Certain segments of the first commutator and certain segments of the second commutator are electrically connected. The motor also includes a brush card assembly including a high speed side having first brush structure associated with the first commutator, and a low speed side having a second brush structure associated with the second commutator, and switches for selectively connecting a D.C. voltage in such a way as to cause the armature assembly to rotate at a first speed and a second speed.

A high frequency rotary transformer for an electrical machine includes a primary transformer component having a primary transformer winding, and a secondary transformer component having a secondary transformer winding. The primary transformer winding is configured to be coupled to a DC power source via a DC to AC converter. The secondary transformer winding is configured to be coupled to a winding of the rotor. Each of the primary and secondary transformer components are mechanically coupled to either the stator or the rotor. The secondary transformer component is configured to rotate with respect to the primary transformer component to produce a magnetic flux via the primary transformer winding and the secondary transformer winding.

A brushless direct current (BLDC) motor that generates electrical energy (AC voltage) while operating as a motor. The motor is configured with a dual purpose stator assembly wherein one segment of the stator assembly includes coil windings to produce the rotary force (torque) in the rotor and the other segment of the stator assembly includes coil windings to generate electrical energy. The stator windings for producing torque are electrically connected through commutation control circuitry to a DC supply source, and the stator windings for generating electrical energy are connected to a load or to an energy storage system. Thus, the embodiment offers a novel means for generating electrical energy in the conventional BLDC motors. Because the motor can generate electrical energy while operating as a motor, it can effectively serve as a powertrain in electric vehicles, whereby the electrical energy it generates can be used to extend the vehicles' drive range.

An electric motor includes a stator which carries permanent magnets, and a rotor which carries electromagnets. A particular arrangement of connecting up the windings of the electromagnets to the distributing collector and the selection of the ratio of stator magnets to rotor electromagnets enable higher torque to be achieved. The main field of application is in motor-wheels of vehicles.