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| Number | Title | Issue Date |
| 8159850 | Converter control device A converter control device includes a converter device formed by three converter circuits connected together in parallel between a secondary battery as a first power source and a fuel cell as a second power source. A control unit includes: a PID control module for c... | 04/17/2012 |
| 8009452 | Multiple driver power supply A power supply includes a power source having at least one power source output, and a plurality of drivers connected to the at least one power source output. At least one of the plurality of drivers includes a bridge network having a first switch, a second switch an... | 08/30/2011 |
| 7701740 | Apparatus for three phase PWM cycloconverter A power conversion method comprising detecting a three-phase source voltage of the three-phase AC power supply every control sampling cycle. The three-phase source voltage is allocated to a maximum voltage, an intermediate voltage and a minimum voltage as seen from ... | 04/20/2010 |
| 7633783 | Converter control device A converter device which is configured by connecting three converter circuits in parallel is provided between a secondary battery serving as a first power supply and a fuel cell serving as a second power supply. A control unit includes a PID control module which con... | 12/15/2009 |
| 7511979 | Automatic phase converter Systems for converting single phase power to three phase power are well known, however, these systems may be noisy and wasteful of electrical power because they are prone to being left on for long periods of time when three phase power is not required. To overcome t... | 03/31/2009 |
| 7483282 | PWM method for cycloconverter A method of using a cycloconverter switches a first switch of the first topology type to an on state after a magnitude of a current through an output inductor becomes less than a predetermined current threshold, and switches a second switch of the first topology typ... | 01/27/2009 |
| 7375996 | Reduced rating T-connected autotransformer for converting three phase AC voltages to nine/six phase shifted AC voltages The invention provides a T-connected autotransformer for converting three-phase ac input voltages to nine phase shifted ac voltages feeding three sets of three-phase diode rectifier bridges. The nine phase shifted voltages are at an angle of +20 degree or −20 degr... | 05/20/2008 |
| 7332976 | Poly-phase frequency synthesis oscillator A frequency synthesis/multiplication circuit and method for multiplying the frequency of a reference signal. In one embodiment, multiple versions of the reference signal are generated having different phases relative to one another, and these multiple versions are c... | 02/19/2008 |
| 7321835 | Method for improving the mode of operation of a matrix converter A method for operating a matrix converter in which m phases of a generator generating alternating voltage with n (n | 01/22/2008 |
| 7309973 | Mitigation of harmonic currents and conservation of power in non-linear load systems An AC power controller system applies three-phase AC operating power to an induction motor that drives a non-linear mechanical load. A primary low pass filter is connected in series between branch phase conductors and a power controller of the type that uses gate-co... | 12/18/2007 |
| 7276882 | Regulator control circuit and method Switching devices control the rectification and flow of alternating current power from a source such as an alternator to a load such as a battery in response to both the voltage of the battery and a minimum selected time period that is selected to eliminate or reduc... | 10/02/2007 |
| 7196435 | Solid state relay and method of operating the same A solid state relay coupleable to first and second phase busses of an AC power source for switching power from the first and second phase busses to a load comprises: first and second power semiconductor switches connected in a series circuit configuration and couple... | 03/27/2007 |
| 7196436 | Solid state relay for switching AC power to a reactive load and method of operating the same A solid state relay coupleable to first and second phase busses of an AC power source for switching power from the first and second phase busses to a load including a reactive component comprises: first and second power semiconductor switches connected in a series c... | 03/27/2007 |
| 7187149 | Commutation technique for an AC-to-AC converter based on state machine control A system for controlling a commutation of a load current is provided. The system comprises a AC-to-AC converter that includes a plurality of switching elements, an energy source that provides an oscillating voltage and is connected to the converter, an electrical lo... | 03/06/2007 |
| 7030593 | Multiple path variable speed constant frequency device having automatic power path selection capability The present invention relates to variable speed constant frequency (VSCF) devices and methods for maximizing engine generator efficiency. In one embodiment, a VSCF device may include at least two paths for conducting power to the load. One path, a line inductor path... | 04/18/2006 |
| 6771524 | Multiple PWM cycloconverter A multiple PWM cycloconverter or matrix converter uses reactors to connect various phase output terminals in parallel. ... | 08/03/2004 |
| 6744650 | Method for controlling a matrix converter A method is described for controlling a matrix converter which includes nine bi-directional circuit-breakers arranged in a 3×3 switch matrix. A commutation sequence is selected based on detected linked input voltages and a predetermined limit value and compared wit... | 06/01/2004 |
| 6731525 | H-bridge electronic phase converter A phase converter that converts single phase AC electric power to balanced three phase AC power. Two input terminals are connectable to a single phase AC power source, and connect directly to two output terminals of the converter. The phase converter has a storage c... | 05/04/2004 |
| 6552510 | Method for frequency converter A method for a frequency converter, when the frequency converter controls a motor and operates torque-controlled partly or entirely in a field weakening region. The method comprises the steps of defining the direction of travel and sector of a stator flux... | 04/22/2003 |
| 6344988 | Power unit A power unit is provided which can perform stable feedback control by reducing a feedback gain, and sufficiently cope with fluctuations in the output voltage occurring according to fluctuations in the input voltage caused by fluctuations in the rotational... | 02/05/2002 |
| 6016257 | Voltage regulated power supply utilizing phase shift control A power supply, including a resonant circuit having an output voltage and a current oscillating therethrough, and a voltage-fed half-bridge inverter producing a source voltage at an output coupled to the resonant circuit. The inverter is responsive to a d... | 01/18/2000 |
| 5995391 | Control arrangement for a multilevel convertor A control arrangement for a multilevel convertor employs an AC reference signal which is locked to the AC system frequency and is compared with a number of DC threshold levels. Intersections of the reference signal and threshold levels triggers the firing... | 11/30/1999 |
| 5959858 | Electric power conversion apparatus A sine wave input converter provided with a phase sequence computation unit which inputs two line voltages or two phase voltages of the three phase ac power supply, computes the phase of a sine wave voltage of one of these two inputs, and determines on th... | 09/28/1999 |
| 5856920 | Method and apparatus for estimating a phase error between two independent timebases A phase control system has a stable timebase phase reference generated by an internal phase reference generator which has improved transient response in the presence of spurious noise generated by other external equipment coupled to the same voltage sourc... | 01/05/1999 |
| 5388031 | Three-phase to single-phase power supply converter for welding equipment A power supply unit comprises three input terminals connected to a three-phase A.C. power supply, a phase control circuit controlling the firing of the three-phase A.C. for each phase, and a transformer comprising a single-phase iron core wound by first t... | 02/07/1995 |
| 5297016 | Polyphase emulator for single phase circuit An emulator which is able to operate on a standard single phase 120 VAC line, generates simulated three-phase alternating current in order to demonstrate the operation of a polyphase electricity meter. The emulator is also capable of demonstrating the ope... | 03/22/1994 |
| 4887018 | Line to line to line to neutral converter A reduced voltage starter for gradually starting a polyphase motor having an acceleration control circuit for gradually applying power to the motor and detector circuits for detecting various fault conditions for terminating power to the motor. A shorted ... | 12/12/1989 |
| 4719560 | Rotary phase generator and system 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... | 01/12/1988 |
| 4459535 | H-Switch start-up control and frequency converter for variable speed AC motor A simple combinational technique is disclosed using one or more H-switches for start-up control and frequency conversion in an AC motor. A coordinating logic system provides H-switch toggling timing patterns yielding phase shifted voltage waveforms in the... | 07/10/1984 |
| 4459532 | H-Switch start-up control for AC motor A start-up control technique is disclosed for an AC motor. At least one H-switch connects a motor winding to a pair of AC-supplied power lines and is switched between designated states to yield a fundamental frequency component voltage waveform in the win... | 07/10/1984 |
| 4445078 | Processor module for power factor controller A motor control circuit utilizes sample and hold circuitry whose operation is initiated by an analog switch to control the firing angle of silicon control rectifiers, thereby to minimize wasting of power supplied to the motor being controlled.... | 04/24/1984 |
| 3976930 | Controlled static convertor for motor control and control angle limiting arrangement A controlled static convertor has terminals for connection to an alternating current source and includes controlled rectifiers and a control pulse device for delivering control signals to the rectifiers. The control pulse device includes arrangements for ... | 08/24/1976 |
| 3971972 | Transistor inverter motor drive having voltage boost at low speeds A transistor inverter drive provides variable frequency and variable voltage power to an electric motor and pulse width modulates a predetermined number of harmonic-reduced constant volt/hertz pulses per cycle of motor frequency to selectively vary the mo... | 07/27/1976 |
| 3959709 | Multi-phase power supplies Apparatus for converting a single-phase power supply to multi-phase operation in which at least one phase of the multi-phase supply is generated by applying the single-phase to the input of a bridge network, each arm of which contains at least one switch ... | 05/25/1976 |
