Abstract: In a propulsion system for hybrid vehicles, etc., a failure detection system that detects the occurrence of failure that obstructs a phase current supplied to an electric motor for propulsion. The direct current of the battery is converted to three-phase alternating current by an inverter and supplied to the electric motor. The controller drive controls the inverter so that the output torque of the electric motor attains a target torque. Each of the phase currents supplied to the electric motor are detected by a current sensor, and provided to a comparator. The comparator compares the value of each of the detected phase currents and the current limit value calculated by the current limit value calculation circuit, and outputs a signal showing that a current phase has abnormally risen. This signal is counted by the counter, and the occurrence of failure is identified based on this count value.

Abstract: A motor system utilizes a master three-phase induction motor driven by a single-phase power supply which the motor has six-windings connected in a symmetrical double DELTA or double WYE configuration with appropriate running capacitors to provide when the motor is running a balanced three-phases of voltage potentials. The potentials have been tapped off to run satellite three-phase induction motors.

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: An apparatus and method for driving a three-phase motor from an AC energy source includes a converter connected between the energy source and an inverter. The inverter includes two inverter circuits controlled by a logic circuit. The outputs of the inverter circuits have a phase angle therebetween of 60° and are connected directly to two inputs of the motor. The remaining motor input can be connected to either the first or second line of the energy source. Both the frequency and the magnitude of the voltage waveforms can be varied to control the speed of the motor.

Abstract: A switching filter is disclosed for discriminating false control signals from actual control signals. The switching filter is particularly useful on a high impedance input, such as that of a motor controller. The filter is designed to compensate for capacitive, inductive, and/or resistive coupling between extended control lines that are run in parallel with other power lines. A low impedance is switched into the otherwise high impedance control line input for a brief instant to dissipate and phase shift false control signals to prevent the controller from interpreting the false signals as actual control signals. The filter includes a first resistor connectable to sense a presence of a possible false control signal, and a second resistor, having much lower resistance than the first resistor, connected in a path between the control line input and circuit common.

Abstract: A multiple pulse-width modulation power conversion device for variable-speed drive of a three-phase AC motor comprises three units (11.sub.1, 11.sub.2, and 11.sub.3), each unit including n (n.gtoreq.2) batteries (12.sub.11, 12.sub.12, and 12.sub.13), each made up of a DC power supply or at least one battery cell, and n power converters (13.sub.11, 13.sub.12, and 13.sub.13) for converting the DC power of each of these batteries to single-phase AC power. Single-phase AC terminals within each unit are connected in series, and of the single-phase AC terminals within each unit, one of the single-phase AC terminals that is not connected to the single-phase AC terminal of another power converter is connected to a star connection, and the other is connected to a respective one of three input terminals of a three-phase AC motor. The power conversion device further comprises control circuits (14.sub.11, 14.sub.12, . . . , 14.sub.

Abstract: A method and apparatus for monitoring a three-phase electric motor which has been disconnected from the electrical mains and is running down, one phase of the voltage generated by the motor being checked respectively in each of two channels for zero crossings and, if a zero crossing occurs, a signal being produced which, after DC-decoupling, is used to control the operation of a safety device. The safety devices are mutually interlocked and control signals therefor are produced only when the period between zero-crossings detected in both channels indicates that the motor output shaft has ceased rotation.

Abstract: An improved method of starting three-phase and three-winding induction motors from a single phase supply reconfigures the 6 accessible windings of a standard induction motor into first an optimal starting configuration which, for example, may reduce starting torque or starting current and then an optimal run configuration. One example of a run configuration is a normal delta along with an inverted delta; another example is a (voltage phasor half-hexagon) run configuration where the windings are all series connected with 120.degree. phase differences.

Abstract: A converter for providing three phase power to a three phase load from a single phase supply includes an inverter connected to single phase input power lines and a bi-directional switch connected in series with one of the input power lines. The converter has three output lines, one connected to the inverter output, another connected to an input power line between the bi-directional switch and the inverter, and the third connected directly to the other input power line. The inverter switching devices are controlled to provide a signal on the output of the inverter to provide balanced three phase power on the converter output lines. This is preferably accomplished by pulse width modulation of an inverter output voltage reference signal derived by phase shifting the single phase input voltage signal by 60.degree.. The inverter is preferably also controlled to phase shift the inverter output signal when necessary to ensure that the net power flow into the inverter is zero under light load conditions.

Abstract: A packaging for high-power devices such as Insulated Gate Bipolar Transistors includes a direct bonded copper substrate (DBC), such as beryllium oxide (BeO), soldered directly to a heat generating surface of the high-power device. The direct bonded copper substrate (DBC) is, in turn, soldered directly to a liquid cooled heatsink (HS). The packaging improves the thermal management of the heat generated by the high-power device, and is applicable for use in a switching circuit for a 3-phase electric traction motor (M). The assembly also provides for improved wirebonding design in order to use each high-power device to its fullest.

Abstract: A method and device are disclosed for speed control of an AC induction motor by means of a control circuit which generate a motor drive voltage consisting of a combination of AC and time-spaced DC pulses. During the occurrence of the time-spaced DC pulses in the motor's AC drive voltage a back EMF suppression network is activated to absorb the motor's generated back EMF energy. A further feature of the invention is a slow down mode where the motor is decelerated from continuous full cycle AC to a requested slow speed setting by means of a higher contend of DC pulses in the AC drive voltage.

Abstract: An electronic control apparatus to operate an alternating current induction motor protecting same from power line blackouts, brownouts and providing self-adjusting, linearized, non-stepped reduced voltage output coinciding to work load to enhance efficiency, thereby reducing electrical energy used by the motor. This apparatus can be utilized in conjunction with a refrigerator, air conditioner or almost any home appliance to yield a substantial savings in electrical use.

Abstract: A three phase motor conversion and monitoring circuit converts a three phase motor to be started and run on single phase line power. During motor start-up, the circuit connects a start capacitor across a first input pair of the motor via a normally closed relay contact. The circuit includes a power supply connected across a first motor input pair which powers both a voltage monitor connected across a different input pair and a phase sequencing detector. When normal run voltage is detected across the first and second input pairs, and if and only if the phase sequencing detector has detected a normal phase sequence indicating that the motor is rotating in the correct direction, the relay is operated to open the normally closed contacts and to remove the start capacitor from the motor circuit.

Abstract: A standard three-phase induction motor wherein two motor windings are connected across a single phase power supply, and a center-tapped autotransformer is connected between the third motor winding and one of the other motor terminals. A capacitor provides an injected current of a suitable phase angle for the third motor winding by being connected between the center tap and the second one of the other motor terminals. This same concept can also be used for a rotary-phase converter to generate three-phase voltage from a single phase line. The three-phase voltage can be used to supply several three-phase motors.

Abstract: To enable a gentle switching back of a change-pole motor to a low speed while ensuring the full moment or torque on passing into motor operation, a method for switching back the change-pole motor to the lower speed is proposed wherein initially there is a two-phase switching back to the lower speed, and wherein, on dropping below the predetermined switching current, the third phase is switched in. For this purpose, an ammeter is provided in the switched-in phase, with a comparator being provided for comparing the actual current with the predetermined switching current, and with a switch also being provided in the third phase to be switched in.

Abstract: A converter, for providing three phase power to a three phase induction motor from a single phase supply, includes an inverter connected to the single phase input power lines which has two switching devices, and a bi-directional switch connected between one of the single phase input power and one output line to the motor. The other two outputs provided to the motor are a direct connection from the other AC input line and the output of the inverter. In a first or start-up mode of operation, the bi-directional switch and the inverter are controlled to provide currents to the motor which are at a fundamental frequency lower than the single phase AC input frequency to provide controlled start-up of the motor with limited in-rush current. After the motor has started, the converter may be switched to a second mode wherein the bi-directional switch is turned off and the inverter provides single phase power at increasing frequency to the motor to drive the motor up in speed.

Abstract: A drive control apparatus for controlling a motor to drive the compressor of an air conditioner, according to the present invention, includes a rectifying circuit for converting an AC voltage into a DC voltage, an inverter having a combination of a plurality of power controlling semiconductor devices and which controls the DC voltage from the rectifying circuit in accordance with a drive signal supplied to the combination of the semiconductor devices so as to generate an AC drive current to the drive, and a drive circuit for generating the drive signal to the inverter. The drive circuit formed as a monolithic integrated circuit having a dielectric separation structure, with the monolithic integrated circuit and the inverter being mounted on a common module substrate.

Abstract: A three-phase induction motor is driven efficiently from a single-phase power supply by reconnecting the motor windings and using two or more capacitors to provide balanced currents and voltages in the windings at preselected values of power. A similar method is used to drive a three-terminal conventional motor from a single-phase supply by using a tapped autotransformer with two different voltages and two different capacitors to excite the third motor terminal. Capacitor switching in all embodiments is controlled by feedback from the voltage across the winding with capacitor excitation.

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: An apparatus for converting single phase input power to three phase output power supplied to a motor includes a pair of input lines, and a pair of DC bus lines, a pair of capacitors, a pair of diodes, and a pair of controlled switching devices which are each connected between the DC bus lines. One of the input lines is connected to the node between the capacitors and the other input line is connected to the node between the diodes. Two output lines are connected to the input line and a third output line is connected to the node between the two switching devices, with the three output lines being connected to a motor to supply three phase power to the motor. The switching devices are switched in a pulse width modulated manner to provide a voltage between the third output line and the other two output lines which provides the three phase power. During motor startup, at least one startup capacitor is switched in between one or both of the input lines and the output lines to provide startup torque for the motor.

Abstract: For operating electric drives, in particular of two-pole and multi-pole asynchronous induction motors intended for driving devices having at least two significantly different operating speeds it is proposed to operate at least one two-pole or multi-pole multi-phase asynchronous induction motor from a single-phase mains supply (L, N) by rendering conductive each of a plurality of power semiconductors (Triac T1, T2, T3) being connected in series to one of the windings (W1, W2, W3) each, only during a half wave of the single-phase supply voltage, in a manner staggered in time relative to the other series-connected semiconductor switches, and successively relative to the latter (FIG. 1).

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: An electric floor cleaner is of the type arranged to drive a three-phase motor, whose rated voltage is substantially equal to a voltage obtained by voltage doubling and rectifying a single-phase commercial power line and then by converting a voltage doubled d.c. voltage into three-phase a.c. by an inverter. The voltage and frequency of the three-phase a.c. output from the inverter are controlled for a predetermined period of time after a power switch is put into a turned on state from a turned off state. It is therefore possible to reduce the starting current to a small value enabling the use of a larger rated output motor than a motor in a conventional system within an allowable current limit of a commercial power line.

Abstract: In a power converter apparatus, variations contained in a single-phase AC input voltage cause a beat phenomenon in a three-phase DC/AC inverter. To avoid such a beat phenomenon, the single-phase AC input voltage is converted into a DC input voltage having ripple components and the ripple components are filtered from the input voltage so as to derive an input DC voltage. The input DC voltage is inserted into a three-phase AC voltage. Variations contained in the single-phase AC input voltage are detected to obtain a variation detecting signal and the inversion is controlled in a pulse width modulation control mode based upon the variation detecting signal and a reference signal.

Abstract: A three-phase induction motor is efficiently driven by a single phase power supply by, in one embodiment, splitting the three windings into six, connecting them in two symmetrical motors, with two of the winding pairs connected to each other. The resulting 4-terminal motor is placed across the single phase supply with appropriate capacitors providing balanced currents. For better efficiency, feedback control, along with transformers, may be used.A similar feedback, transformer technique, may be used on a standard three terminal three-phase motor. Lastly, for such a motor, the foregoing techniques may be applied to a three wire residential power supply.

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: The present invention discloses a speed control apparatus for an AC motor which vector-controls, for example, a drive current of the AC motor such as an induction motor, synchronous motor and AC commutator motor with a feedback current control loop providing an inverter utilizing a semiconductor element for power amplification such as power transistor and compensates for non-linear current characteristic of the drive current generated by dead time resulting from ignition delay of a semiconductor element with a current compensation control element provided within the current control loop, thereby controlling the rotation speed and command response speed of an AC motor.

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: A frequency converter is provided for a three-phase electric motor and has input connections for a multi-phase alternating current electric supply source, and output connections for connection to a three-phase electric motor. A SCR bridge including a plurality of SCRs interconnects the input connections and the output connections. A trigger circuit is connected to the SCR bridge for selective firing of the SCRs, in response to timing pulses generated upon zero crossing of the input means phases. Logic circuits interconnecting said timing pulse generators and the trigger circuits for effecting selective sequential firing of the SCRs at the zero crossings. Firing of said SCRs is respectively terminated by natural commutation. In one embodiment of the invention single phase current is converted to multiphase current.

Abstract: An apparatus for converting a single phase electrical signal into a three phase electrical signal is disclosed. A converter includes a rectifier connectable to a single phase electrical power source. One output of the rectifier is connected through a smoothing ciruit to four switching transistors. The other output of the rectifier is connected to center taps of a first and a second load coil. The first phase load coil is connected across a first pair of the switching transistors and the second phase load coil is connected across a second pair of the switching transistors. Third and fourth phase load coils are connected to opposite sides of the first and second phase load coils. The first, second, and third phase load coils are delta connected and the first, second, and fourth phase load coils are delta connected. The first and second pairs of switching transistors are controlled by first and second pairs of phase shifting signals.

Abstract: A reverse-conducting GTO thyristor comprises a gate turn-off thyristor and a diode which are formed on a single semiconductor substrate so as to have a common layer and be connected electrically in an inverse-parallel connection. A power converter is composed of a plurality of pairs of these reverse-conducting GTO thyristors connected in series, each pair of thyristors being controlled so that they are turned on and off in opposite phases. An OFF gate pulse for one of each pair of thyristors continues from a time on or after the generation of an ON gate pulse for the other thyristor to the time when a recovery current flowing through the diode portion of the first thyristor is extinguished. The thus-extended OFF gate pulse functions to prevent any displacement current flowing through the GTO portion of the first thyristor during the recovery time for the diode portion thereof.

Abstract: An inverter apparatus for converting a single-phase A.C. power source to three-phase A.C. outputs is described wherein the single-phase power source is directly connected to a first phase load and is connected through a one-phase converter to a second phase load, and the single-phase power source and the one-phase converted single-phase power source are connected to a third phase load and a fourth phase load, the third and fourth phase loads being formed by dividing a single load, so that three-phase power outputs are provided for the first phase load, the second phase load, and the third plus fourth loads.

Abstract: A circuit which enables a three phase, Y connected motor to be operated on either one phase or three phase power at either 230 or 460 AC line voltage. A modified circuit includes power factor correction capacitor banks for increasing the power factor and efficiency of the motor whether connected for one phase or three phase operation at either line voltage.

Abstract: A three-phase delta-wound motor adapted for operation from a source of single-phase current, which motor includes first and second terminals adapted to be connected to the single-phase current source and substantially identical first, second, and third phase windings. A capacitor and the first and second phase windings are series-connected one with the other across the first and second terminals, the polarity of the first winding with respect to the second winding being opposite that of a normal delta-wound motor. The third phase winding is connected directly across the first and second terminals in parallel with the serially-connected capacitor and first and second phase windings.

Abstract: This disclosure is concerned with a motor technique for generating speeds that are fractions of synchronous speeds, through novel time-staggered selected half-cycle energization of a plurality of magnetic poles by a controlled switching sequence, generating such a fractional motor speed that would otherwise have to be produced by a much larger number of magnetic poles.