Abstract: An apparatus and method is disclosed for an improved AC--AC series-resonant converters incorporating power pulse modulation with internal frequencies of tens of kHz is applied to a series-resonant converter system for generating synthesized multiphase bipolar waveforms with reversible power flow and low distortion. The high pulse frequency allows the application of the principle of modulation and demodulation for fast system response. Switches are required which have bidirectional current conduction and voltage blocking ability. The conventional series-resonant AC--AC converter applies a total of 24 anti-parallel thyristors. The circuit configuration of the present invention is a series-resonant AC--AC converter with only 12 thyristors. Use of the converter results in a higher efficiency and lower costs.

Abstract: A method of operating a three-phase converter to produce a signal at an output frequency by decoupling and digitally sampling inverter input signals and load voltage signals and feeding the resultant phase signals back into the inverter. The phase voltages activate switching elements in the inverter to switch signals a plurality of times within one cycle of the output frequency thus changing electrical power at a first frequency, including direct current, to A.C. power at the output frequency.

Abstract: A system for converting variable frequency multiple phase current into multiple phase current of constant frequency with a neutral having a multiple phase inverter with a neutral (N) is disclosed. A first input (34) is connected to the multiple phase inverter for receiving pulses of a positive polarity. A second input (36) is connected to the multiple phase inverter for receiving pulses of a negative polarity. A variable frequency multiple phase source (12, 14 and 16) of alternating current applies current to a multiple phase transformer (80, 142 and 180). Current from the transformer is applied to a full-wave rectifier (96) which has a first group of diodes (112) which applies the positive pulses to the input (34). A second group of diodes (116) applies the negative pulses to the input (36). The ripple frequency f.sub.

Abstract: The generator set comprises an internal combustion engine (5) driving a three-phase generator (6). The latter is surmounted by a casing (7) containing a converter (8) which is supplied with power by the generator (6) and provides a current of 42 V at 200 Hz at the socket (11).

Abstract: In a power conversion system, a DC voltage of a DC power supply is converted into a predetermined high-frequency voltage by an inverter, and a high-frequency low voltage generated from the inverter is converted into a high-frequency high voltage by a transformer. A high-frequency high voltage generated from a secondary winding of the transformer is converted into a predetermined low-frequency voltage by a frequency changing circuit. The commutating operation of the frequency changing circuit is performed by a control circuit in response to the output current of the frequency changing circuit and in synchronism with the starting time of the short-circuiting prevention period of the inverter. As a result, the converted output of the power conversion system is prevented from decreasing.

Abstract: A high voltage transformer assembly for use in a high frequency medical X-ray generator comprises a plurality of transformers, a plurality of filter capacitors, and a pair of capacitor printed circuit boards for mounting the capacitors and for coupling the capacitors in electrical circuit to define a plurality of relatively high power handling capacitance circuits. A plurality of diodes are provided, and diode printed circuit boards mount the diodes and couple the diodes in electrical circuit to define a plurality of relatively high power handling diode circuit elements. A frame, and top and bottom plate-like members, and other joining structure join together the frame and the top and bottom plate-like members, and the capacitor printed circuit boards to form an enclosure wherein the top and bottom plate-like members and the capacitor printed circuit boards comprise four sides of a generally rectilinear, six-sided enclosure.

Abstract: A highly innovative new technique of developing AC to DC power sources for various applications has been described. Such technique of generating DC power is different from the conventional linear and switching power conversion techniques and this new technology has been called the Solid State Power Supply (SSPS) Technology. The principle of operation depends upon high-frequency pulsed power switching followed by high energy charge-discharge principles as applied to power conversion technology. The use of fast turn-on power MOSFETs enables the application of high frequency switching on this power technology. While the non-isolated SSPS is claimed to be transformerless, the isolated SSPS requires the use of a transformer for input-output isolation. The input and output filtering is reduced tremendously, thereby reducing the size of such power supplies.

Abstract: A power conversion apparatus comprises an inverter for converting a voltage of a DC power source into AC power having a frequency higher than the commercial frequency, a transformer, fed by the inverter, for outputting AC power, which is adjusted at a desired voltage, a frequency converter, formed by two pairs of two gate turn-off thyristors (GTOs) connected in reverse-parallel, for converting the frequency of the AC power supplied from the transformer into the commercial frequency, and an energy regenerating device having capacitors for absorbing the energy of a spike voltage occurring due to a circuit inductance upon interruption of a current of each GTO of the frequency converter and a bridge circuit, formed by GTOs and diodes connected in reverse-paralel therewith, for switching over the direction of connecting the capacitors with a secondary winding of the transformer in accordance with the polarity of a voltage of the secondary winding in such a manner that the energy stored in the capacitors is regener

Abstract: A quick-response frequency-voltage converting circuit which generates a voltage signal responding to a reciprocal of the period of an input signal, and sample-holds this voltage signal at the end of one period, and thereby can obtain a voltage responding to the frequency of the input signal in one period.

Abstract: In a system comprising an asynchronous generator rotatable at variable speeds, and a main electrical network carrying power at a substantially constant voltage and frequency, the improvement comprising a synchronizer having an electronic optimization controller connected in circuit between the generator and the network, the synchronizer being capable of receiving electrical power at variable voltages and frequencies from the generator and controllably and continuously injecting the power into the network at substantially constant voltage and frequency. A method for optimizing the generation of electrical power into the mains is also claimed.

Abstract: A device for converting DC to RF has a monolithic PIN diode adapted to be coupled to a DC supply. The diode receives light switching pulses and is coupled to a monolithic resonator. The monolithic form provides compactness and reliability, while the diode, which is reversed biased when OFF, prevents substrate leakage currents. The diode and the resonator can be made in a single substrate, e.g., silicon, or in different substrates, e.g., silicon for the diode to obtain a long carrier lifetime and, thus, minimize the light pulse repetition rate, and GaAs for the resonator to obtain a high Q. The resonator can also act as an impedance transformer.

Abstract: A power source using high-frequency phase control possessing an ability to cause the transfer of electric power between a power source side and a load side to be made through a high-frequency transformer and to effect control of the output voltage by subjecting the power source side and the load side circuits to on-off control with a certain phase difference. This power source can be used as an uninterruptible power source, a device for controlled drive of a motor, a DC constant-voltage power source, or a constant-current device, for example.

Abstract: A high tension power supply for use in an x-ray tube drive circuit which uses a step-up transformer to raise an input line signal to the desired voltage level. A partially open bridge or other suitable means permits only half cycles, for example positive half cycles, of the transformer output to be applied to fire the x-ray tube. Saturation of the transformer core during unused half cycles, for example negative half cycles, is prevented by adding a compensating impedance in series with the circuit passing the unused half cycle to the transformer primary, the increased voltage drop across this impedance as current increases in response to the transformer approaching saturation reducing the voltage across the transformer so as to maintain the average voltage across the windings during both half cycles substantially equal. This achieves "constant phase" exposures without transformer saturation.

Abstract: A voltage/frequency converter is formed of a V/F converter circuit which converts an input potential into a frequency corresponding to the instantaneous value of the input potential, and a difference detection circuit which generates an output corresponding to the difference between the output frequency of the V/F converter circuit and a predetermined reference frequency. The V/F converter circuit is controlled according to the level of the output from the difference detection circuit, thereby reducing the deviation of the output frequency of said V/F converter circuit from the reference frequency.

Abstract: An electronic transformer comprising first and second switching converters for converting the positive and negative half periods, respectively, of an input alternating voltage into high frequency voltages, which are rectified to produce an output alternating voltage at the input voltage frequency. The converters are constructed as fly-back converters with the choke coils as well as the output and input capacitors combined into elements common to the two respective high frequency fly-back converters. First and second backward diodes are connected parallel to each switching transistors of the two fly-back converters and each converter includes an auxiliary switching transistor switching at the input frequency to change over the converters from one half period to the other of the input AC voltage.

Abstract: A DC to low frequency AC power conversion system includes two high frequency link inverters and a cycloconverter. DC input is fed to the high frequency links in parallel, and the outputs of the links are fed to a subtractor. The output of the subtractor is then fed to the cycloconverter. The difference between the first high frequency and the second high frequency of twice the respective frequency links is equal to the low frequency.

Abstract: A circuit including a dc/ac converter for supplying an ac consumer with an alternating voltage, such as a sinusoidal voltage, from a dc voltage source has an auxiliary load circuit which is connected in parallel with the ac consumer, the auxiliary load circuit being switched into the overall circuit by a controlled switching element. The control electrode of the controlled switching element is connected to the output of a voltage comparator, having inputs respectively supplied with an actual voltage derived from the voltage being used by the ac consumer and a theoretical signal derived from the output voltage of the dc/ac converter or from a reference oscillator which controls the converter. The controlled switching element becomes conductive when, as a result of the release of electrical or magnetic energy stored in reactive impedance components, the voltage used by the ac consumer exceeds an instantaneous value of the theoretical signal.

Abstract: Electrical circuits, apparatus and methods for a variety of applications. A switching device subdivides an alternating current input signal into a plurality of lower voltage pulses by switching on and off in response to the characteristics, such as the voltage and current, of the input signal, and the pulses of current are intermittently passed to a capacitor in series with the device as the voltage on the input signal is positive-going. When the voltage becomes negative-going, the capacitor is discharged, usually with the pulses passing through the switch in the opposite direction. Work is done by energizing the series capacitor, or by energizing a capacitor in parallel with the switch, or by energizing an inductor in parallel or series relation to the switch, or a combination of the above. The inductor may be the primary winding of a transformer, or may create an electrical or magnetic field which is transduced into mechanical motion. The load may also be a resistive load.

Abstract: Apparatus for chopping DC power at a high frequency, for example 20 kHz, such high frequency being pulse-width modulated by a lower power frequency source at the desired power frequency. The pulse width modulation is servo controlled through current and voltage feedback to cause the current delivered to a load impedance to be in phase with a reference to power frequency oscillator and to control the output frequency voltage amplitude.

Abstract: A circuit is disclosed which is responsive to an applied alternating input signal for producing an analog output signal the magnitude of which is made proportional to the frequency of the input signal. A triggering circuit is provided which produces a triggering signal on positive transitions of the input signal. A circuit is included for producing a dual ramp output voltage the peak magnitude of which is varied in accordance with the frequency of the applied input signal. A peak detector circuit samples the dual ramp voltage and holds this value until the next cycle of the input signal wherein the dual ramp voltage is again sampled. The triggering circuit also includes a comparison amplifier for providing control signals the state of which are representative of the respective magnitudes of the dual ramp and peak voltages.

Abstract: A first pulse train has repetition pulses in proportion to the frequency of an input signal. A second pulse train has repetition pulses obtained by shifting the timing phase of the pulses of the first pulse train. One of the pulse trains is used to drive a saw-tooth wave generator circuit, thereby producing a saw-tooth wave voltage, which is supplied to a sample-and-hold circuit, which in turn is driven by the other pulse train so that the saw-tooth wave voltage is sampled and held, thereby producing a DC voltage.

Abstract: An ozone generating apparatus is disclosed which comprises a power source device for feeding a rectangular waveform alternating current between the discharge electrodes of a discharge tube of an ozone generator. One or both of the output current and frequency of the power source device is controlled to overcome the disadvantages of the conventional ozone generating apparatus.

Abstract: An induction heating apparatus includes an inverter circuit, a plurality of output coils for induction heating, a coil selection circuit for selectively connecting the output coils to the output terminal of the inverter circuit, and a control circuit for driving the coil selection circuit and inverter circuit so as to cyclically supply the output of the inverter to any selected one of the output coils for each predetermined time of a predetermined cycle. The induction heating apparatus further includes a plurality of output adjusting means for setting the output period of the respective output coils which is included in the predetermined cycle.

Abstract: An ozone generating apparatus is disclosed which comprises a power source device for feeding a rectangular waveform alternating current between the discharge electrodes of a discharge tube of an ozone generator. One or both of the output current and frequency of the power source device is controlled to overcome the disadvantages of the conventional ozone generating apparatus.