Abstract: A matrix converter according to an embodiment includes a plurality of bidirectional switches and a controller. The bidirectional switches connect each of phases of an alternating current (AC) power supply with each of phases of a rotary electric machine. The controller controls the bidirectional switches to perform power conversion control between the AC power supply and the rotary electric machine. The controller performs on/off control individually on a plurality of unidirectional switching elements constituting the bidirectional switches by using both 120-degree conduction control and PWM control.

Abstract: A sensorless induction motor control device with a function of correcting a slip frequency wherein a slip frequency estimation unit estimates the slip frequency from at least one kind of current flowing through the motor. A voltage command value calculation unit calculates a D-phase voltage command value and a Q-phase voltage command value which are used for controlling a voltage applied to the motor using a Q-phase current command value calculated based on a difference between a speed estimation value, which is calculated using an estimation value of the slip frequency, and an externally supplied speed command value. An ideal voltage command value determination unit determines an ideal voltage command value using the speed command value and the Q-phase current command value. An actual voltage command value calculation unit calculates an actual voltage command value using the D-phase voltage command value and the Q-phase voltage command value.

Abstract: A matrix converter for the conversion of a polyphase alternating current into a desired alternating output current in which m phases of the polyphase alternating current are converted into alternating output current with n (n<m) phases of a load by a multiple number of controllable bidirectional switches. The converter includes at least one stage, and in that at least one stage of the converter each phase of the polyphase alternating current is controlled by a controllable bidirectional switch. The at least one stage of the converter is formed by a two-dimensional array of stage stacks of switching elements which stage stacks are arranged substantially parallel to each other along a stack direction perpendicular to the plane of the matrix converter, and wherein the input of the stage stacks is provided by bus bars located on one side of the stage stacks.

Abstract: A system and method for charging batteries in a system wherein the output of the batteries is converted to alternating current utilizing inverters. The alternating current from the inverters is modified by transformers and variable speed drives to contain properties which enable the alternating current to be used in a power grid to operate conventional electrical appliances. At least two banks of batteries are employed in the system. A unique battery charging device is employed to maintain the two banks batteries in constant substantially full charge. The battery charging device switches between a charge mode for one bank of batteries and a rest mode for the other bank of batteries. The battery charging device constantly and rapidly switches the different banks of batteries between these two modes. A timer controls the amount of time that each mode is applied to each bank of batteries. A solar panel supplies electric power to the charging device to charge the batteries.

Abstract: System, method, and apparatus for commutating and controlling a multi-phase motor using one output rotor sensor and circuitry that measures time between rotor pole-to-pole transitions is disclosed. The exemplary system, method, and apparatus may utilize the polarity of the single-output rotor sensor and the measured time between the polarity transitions detected by the single-output rotor sensor.

Abstract: A method for operating a matrix converter to convert n phases of a generator into alternating voltage with nr (nr<n) phases of a load connected to a network includes the steps of alternatingly connecting the nr phases of the load using a plurality of controllable bi-directional switches disposed in an (n×nr) matrix, wherein nr phases of the generator are always connected with the load and (n?nr) phases of the generator are not connected with the load, and controlling the switching of a phase k of the generator at a time t to a phase c of the grid, using a periodical, continuous, segmented function k(t). The function k(t) defines a broken line having a plurality of segments, wherein each segment i is defined by a starting time ti and a pulsation ?i, and the value of the function k(t) is rounded to the closest integer value.

Abstract: A phase converter for converting single-phase power to three-phase power, wherein the single-phase power is provided at a first and a second single-phase power terminal and the three-phase power is provided to a first, a second and a third three-phase power terminal, the phase converter comprising: a first power transfer means for coupling the first single-phase power terminal to the first three-phase power terminal; a second power transfer means for coupling the second single-phase power terminal to the second three-phase power terminal; and an inverter coupled to receive power from the first and second single-phase power terminals. The inverter provides power to the third three-phase power terminal and a neutral output by phase shifting its input power by ninety degrees.

Abstract: A relatively compact static phase converter is adapted to be disposed within the housing of an appliance, such as a refrigeration unit, making it thus suitable for residential as well as commercial applications. The static phase converter is formed as a modular unit to occupy a relatively small volume, for example, 0.5 cubic feet or less, and is adapted to be disposed adjacent the compressor compartment in a typical refrigeration unit with minimal modification. The static converter includes a balancing coil adapted to be coupled across a source of single phase electrical power, such as 120 volts AC. Two phases of a three phase electrical motor are adapted to be connected in parallel across the balancing coil. The third phase is adapted to be connected to the center phase by way of a running capacitor. Starting circuitry which includes a starting capacitor as well as a control relay is included.

Abstract: A starting system for a rotary dynamoelectric converter is disclosed. The converter is of the type having three sets of windings wired in either delta or wye configuration. Each set of windings consists of two coils normally connected in parallel within the respective winding, and the converter has three leads connected to the delta or wye configurations. Two of the leads are to be connected to a source of single-phase, alternating current, and a run capacitor is connected between one of the first two leads and the third lead, such that three-phase current can be drawn from the three leads when the dynamoelectric converter is running at its normal operating speed. The starting system comprises a mechanism for connecting the two coils in each respective winding in series with each other when single-phase current is initially connected to the first two leads to start the converter.

Abstract: A single-phase to three-phase converter for starting and running a single, three-phase, load carrying induction motor having first, second and third Y-wound stator windings from a single phase power supply comprising a connector for connecting the input conductors to the converter to a source of single-phase alternating current, a connector for connecting the output conductors from the converter to the three-phase induction motor and adapted to connect one single-phase input conductor to the first stator winding and the other single-phase input conductor to the second stator winding, a bank of run capacitors connected between the first powered stator winding and the third unpowered stator winding to develop a voltage in the third winding at a phase angle different from the phase angles in the first and second powered windings, a potential-type relay comprising a set of normally closed contacts and a winding to open them, the windings connected between the second and third stator winding, a slave relay compris

Abstract: A rotary phase generator for generating 3 phase voltage is provided which can operate off of 230 or 460 volts A-C. Also provided is a rotary phase generator which has two groups of running capacitors for providing a stable voltage on the third phase at no load and light loads. In addition, a booster system is provided for a rotary phase generator to provide high starting torque to one or more of the motors operated on the rotary phase generator. A plurality of smaller rotary phase generators may be connected in parallel and started in time delay sequence to eliminate the heavy starting current when starting the system on one phase power.

Abstract: Single phase to three phase dynamoelectric converter for generating three-phase current from a single-phase input comprising a three-phase electric motor generator having first, second and third Y-wound stator windings, a bank of run capacitors connected between the first powered stator winding and the third unpowered stator winding, a normally closed potential-type relay with its winding connected between the second and third stator windings, a normally open slave relay with its winding connected between the first stator winding and the potential relay winding through the set of normally closed potential relay contacts, and a bank of starter capacitors connected between the third stator winding and one of the slave relay open contacts adapted to provide phase shifted starting power to the third stator winding when the single phase energy is applied and disconnect from the third stator winding to allow the converter to run and produce balanced three-phase power that can be drawn from all three stator windings

Abstract: A regulating device for a polyphase electrical circuit, having a motor with windings corresponding to the main supply lines for the circuit. Leads are connected to each of the windings and contain a relatively low m.f.d. capacitor for suppressing spikes and similar transients in the respective supply lines, and a relatively high m.f.d. capacitor for functioning as a phase converter in the event the current in the respective supply line is interrupted. By-pass circuits are provided for each of the low m.f.d. capacitors corresponding to a respective supply line, containing relay means in the circuit responsive to the supply line to by-pass the low m.f.d. capacitor in the event the current is interrupted in the respective supply line, thereby permitting the high m.f.d. capacitor to function as part of a phase converter.

Abstract: A rotary phase converter for connection to a single-phase a.c. power source and adapted to supply polyphase current to a polyphase electrical load. The converter includes a dynamoelectric machine having at least three stator windings and at least first, second and third output terminals, an autotransformer and at least one capacitor. The stator windings of the dynamoelectric machine are oriented symmetrically with respect to each other both physically and electrically and each has a substantially equal number of active turns. The first and second terminals of the dynamoelectric machine are adapted to be connected to the single-phase a.c. power source and they are also outputs of the converter. The autotransformer is connected across the second and third terminals and has at least one tap positioned intermediate the ends thereof to serve as an output of the converter. The capacitor is connected between the first output terminal and the autotransformer tap serving as a converter output.

Abstract: A rotary dynamoelectric machine having a generally annular polyphase stator with a predetermined number of wound poles and an induction rotor. The rotor has a cylindrical laminated ferromagnetic core positioned within the stator for rotation about a central axis thereof when the stator is energized by an a.c. power source. The rotor is of squirrel-cage construction having a plurality of electrically conductive bars each extending the length of the core adjacent the cylindrical surface thereof. Conductive end rings at the ends of the rotor are electrically connected to the ends of the bars at the respective ends of the core. The end rings have a plurality of radial slots therethrough thereby forming a plurality of spaced arcuate ring segments whereby the rotor has a relatively high resistance, e.g., at least three times that of such a squirrel-cage rotor with unsegmented end rings. The stator windings may be interconnected with a source of single-phase a.c.

Abstract: A self-starting rotary converter for connection to a single-phase a.c. power source and for supplying polyphase current to a polyphase electrical load. A generally annular polyphase stator has a predetermined number of poles and at least three stator windings symmetrically oriented physically and electrically. An induction rotor positioned within the stator rotates about a central axis thereof when the stator is energized by single-phase a.c. power. One of the stator windings has at least one electrical tap positioned intermediate its ends, and a second stator winding has one of its ends connected to the tap to effect electrically nonsymmetrical operation of the stator. This maintains the currents supplied to the phases of the polyphase load at its maximum rating substantially balanced.

Abstract: A dynamoelectric machine stator has a primary winding for single phase alternating current input and a secondary winding for polyphase alternating current to be supplied from output terminals. The secondary winding is connected such that at least two frequencies are provided at the terminals. The rotor has two windings thereon for excitation, one being excitable for one frequency output and the other rotor winding being excitable for another frequency output at the secondary terminals. Another secondary winding may be provided on the stator to obtain a desired output terminal voltage at one of the selected frequencies.