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.

A vehicle mounted AC generator system having an AC generator mounted outside the engine / transmission compartment and connected by drive shaft with universal joints and a belt driven RPM ratio device. The ratio is set to provide accurate AC generator RPM at a preselected engine RPM. The AC generator is mechanically engageable when certain conditions are met and is disconnected when other conditions are present, including an operator emergency stop switch.

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.

A multi-port storage system includes a dynamo-electric machine with integral rotor inertia forming a primary energy storage system. The dynamo-electric machine has a primary stator winding configured to accept multiple AC input power sources, and has at least two secondary stator windings configured to deliver electric power to multiple loads at different power, frequency and voltage levels. A secondary energy storage system is coupled to the primary energy storage system, and is configured to convert its stored energy to electric power. The dynamo-electric machine is configured to enhance and buffer the secondary energy storage system, and is configured to improve the conversion of the stored energy to electric power. The system may include a step-up transformer responsively coupled to one of the secondary stator windings. The step-up transformer may comprise a single phase or polyphase step-up transformer having internal cooling and electrical insulation between the secondary windings comprising a hydro-fluoro-ether (HFE) vapor and liquid fluid.

The invention relates to electric motors, particularly to low-voltage gearless commutator motors, and can be used as motor-wheels in transportation vehicles and in other technologies. The aim of the present invention is to provide an electric motor with increased performance characteristics, relatively simple design, and high reliability. A pulsed inertial electric motor according to the invention comprises: (i) a stator with circular magnetic conductor on which an even number of permanent magnets are uniformly arranged with a certain pitch; (ii) a rotor separated from the stator by air gap and bearing an even number of electromagnets, each electromagnet consisting of two coils with opposite winding directions connected in series, which are arranged over the circle in pairs one opposite to another; (iii) a collector distributor mounted on the stator body, containing circularly arranged current-conducting plates separated by insulating spacers and connected with alternating polarity to a dc current source, and (iv) current collectors-brushes mounted on the rotor and capable of contacting with plates of the collector distributor, whereby all brushes are connected to identical (beginning or end) terminals of the windings of said electromagnets and interconnected so that the coils in the opposite electromagnets are connected to each other via one identical terminal and to the opposite brushes via another identical terminal, with the number n of permanent magnets in the stator and the number m of electromagnets in the rotor selected so as to obey the relationsn=10+4k,m=4+2l,where k is an arbitrary integer (k=0, 1, 2, . . . ) and l is any integer such that 0≦l≦k.

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.

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.

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.

An apparatus is provided and includes a hub, including first and second opposing faces, a first sidewall fixed at opposite ends thereof to the first and second opposing faces to define a first interior between the first and second opposing faces and a second sidewall fixed to one of the first and second opposing faces to define a second interior within the first interior, a first assembly, disposed within the second interior, to generate current from input mechanical energy and a second assembly, electrically coupled to the first assembly and disposed within the first interior, to generate mechanical energy from current associated with the current generated by the first assembly.