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Showing papers on "Voltage regulation published in 1979"


Patent
21 May 1979
TL;DR: In this article, a voltage regulated DC-to-DC converter is disclosed which is operable over a wide range of input voltage including voltages greater or less than the desired output voltage.
Abstract: A voltage regulated DC to DC converter is disclosed which is operable over a wide range of input voltage including voltages greater or less than the desired output voltage The converter uses an inductor and a capacitor as storage elements, the inductor being composed of two windings having a common junction A transformer having a center tap connected to the common junction of the two windings of the inductor is connected at either end of its winding to ground through controlled switches One winding of the inductor and either end of the transformer winding are connected by respective power diodes to the capacitor which supplies the output voltage to a load The other winding of the inductor is connected to a fourth power diode as a clamping diode Input voltage is supplied to the inductor through a third controlled switch A pulse width modulator connected to the output of the converter alternately closes and opens the switches connected to either end of the transformer winding and also closes the switch supplying input voltage to the inductor each time either of the switches connected to the ends of the transformer winding are closed The duty cycle of the closing and opening of the several switches is adjusted by the pulse modulator to regulate the output voltage

55 citations


Patent
07 Sep 1979
TL;DR: A voltage control apparatus for an electric generator (2-4) for vehicles includes an exciting coil (4), a rectifier (2) for rectifying an a.c. output from the armature winding (3), and a voltage regulator (5).
Abstract: A voltage control apparatus for an electric generator (2-4) for vehicles includes an armature winding (3), an exciting coil (4), a rectifier (2) for rectifying an a.c. output from the armature winding (3), and a voltage regulator (5). The voltage regulator (5) comprises a differential amplifier circuit (26) producing a detected voltage corresponding to a difference between a battery charging voltage and a reference voltage, a comparator circuit (30) comparing the detected voltage with a triangular waveform voltage generated at constant periods and producing a pulsed output voltage, a first driver circuit (51) effecting duty-factor-control of an exciting current flowing through the exciting coil (4) in response to the pulsed output voltage, and an initial excitation circuit (32) for causing a predetermined small initial exciting current to flow through the exciting coil (4) intermittently during a time interval after the start of the electric generator (2-4).

50 citations


Patent
04 Sep 1979
TL;DR: In this article, a full-wave rectifying network provides a rectified output voltage signal corresponding to the highest magnitude secondary voltage signal, and a comparator issues a circuit breaker trip initiating signal when the output voltage signals achieves a pre-selected threshold voltage.
Abstract: Air core current transformers respectively linked with the phase conductors of a power distribution circuit develop secondary voltage signals proportional to the rates of change of the phase currents. A full-wave rectifying network provides a rectified output voltage signal corresponding to the highest magnitude secondary voltage signal. A comparator issues a circuit breaker trip initiating signal when the output voltage signal achieves a pre-selected threshold voltage.

49 citations


Patent
18 May 1979
TL;DR: In this article, a powerline carrier control system with an audio frequency output voltage, an isolation transformer, a coupling capacitor for parallel coupling to an a-c voltage network, and a device for suppressing a line frequency backward voltage is presented.
Abstract: A powerline carrier control installation includes a control transmitter with an audio frequency output voltage, an isolation transformer, a coupling capacitor for parallel coupling to an a-c voltage network, and a device for suppressing a line frequency backward voltage. For coupling the audio frequency output voltage to the a-c voltage network, a resonant circuit tuned to the audio frequency is provided, the resonant circuit capacitance being supplied by the coupling capacitor and the resonant circuit inductance formed essentially by the main field inductance of the isolation transformer, eliminating the need for a separate coupling choke. A device, specifically the powerline carrier control transmitter itself, is equipped to deliver, in addition to the audio frequency output voltage, a line frequency compensating a-c voltage which has a low amplitude in comparison to the line a-c voltage in order to suppress the line frequency feedback transmitted from the network.

44 citations


Patent
26 Feb 1979
TL;DR: In this article, the Fourier transform of a window of the actual voltage and current over a time interval and of the modified current that would flow if the voltage on each side of the time interval was zero was calculated.
Abstract: An electrical power fault protection relay operates when the calculated impedance of the section of the system it protects shows a sudden change. The instantaneous voltage and current is measured. A calculation device then calculates the Fourier transform of a window of the actual voltage and current over a time interval and of the modified current that would flow if the voltage on each side of the time interval was zero. The actual impedance is calculated from the ratio of the Fourier transforms of the actual voltage and the modified current.

32 citations


Patent
26 Nov 1979
TL;DR: In this article, a series switch between the panel and inverter is activated into a conducting state in response to the panel voltage exceeding a predetermined value, provided by connecting a dummy power dissipating load in shunt with the panel while the series switch is cut off.
Abstract: Orderly control of power applied by a photovoltaic solar panel d.c. source to a load is attained despite varying long and short term solar conditions by coupling power from the panel to an inverter in response to the panel voltage exceeding a predetermined level and preventing coupling of power from the panel to the inverter in response to the panel voltage being less than a predetermined level. The switching frequency of the inverter is controlled in response to the panel voltage so that approximately maximum power which the panel is capable of generating is supplied to the inverter for the incident solar energy on the panel at a given temperature. Power is supplied to the inverter by a series switch between the panel and inverter. The switch is activated into a conducting state in response to the panel voltage exceeding a predetermined value. The panel voltage controls the turn-on and turn-off levels of the series switch by a hysteresis effect, provided by connecting a dummy power dissipating load in shunt with the panel while the series switch is cut off. The dummy load has a value causing the panel output voltage to be less than the voltage for maximum panel output power. A similar series switch and hysteresis control is provided for control circuitry for the inverter. The series switch for supplying power to the control circuitry can be activated in response to the same voltage which activates the series switch for the inverter, or in response to a different voltage level.

32 citations


Patent
25 Jun 1979
TL;DR: In this article, an adjustable speed propulsion engine for a boat also drives an electric generator which supplies electric power to an electric load circuit on the boat, and a solid state electronic control circuit includes time delay means to prevent a transient low voltage condition ("flicker") from causing disconnection of the generator from the load circuit.
Abstract: An adjustable speed propulsion engine for a boat also drives an electric generator which supplies electric power to an electric load circuit on the boat. A solid state electronic control circuit senses when generator voltage departs from a voltage "window" or range defined by preselected low and high voltages (as a result of a departure in engine speed from a cruise speed range to some lower or high speed) and operates a contactor to disconnect the generator from the load circuit to prevent low or high voltage damage to electrical equipment on board. The electronic control circuit operates the contactor to reconnect the generator to the load circuit only when generator voltage rises to a preselected initial turn-on voltage which is above the preselected low voltage but below the normal rated voltage of the generator. The electronic control circuit includes time delay means to prevent a transient low voltage condition ("flicker") from causing disconnection of the generator from the load circuit.

30 citations


Patent
Kern Hans1
26 Dec 1979
TL;DR: In this paper, a circuit arrangement for piezo-electric recording nozzles, in ink mosaic recording devices, to effect a temperature regulation of the control voltages therefor in which the respective recording noZZs are each provided with a control circuit for individually controlling the respective nozzle and which may be individually adjusted, in combination with a regulating circuit which is common to all of the controlling circuits, and includes temperature-dependent means for controlling the regulating means, whereby the latter supplies at its output a voltage which varies in accordance with the environmental temperature at such temperature dependent means.
Abstract: A circuit arrangement for piezo-electric recording nozzles, in ink mosaic recording devices, to effect a temperature regulation of the control voltages therefor in which the respective recording nozzles are each provided with a control circuit for individually controlling the respective nozzles and which may be individually adjusted, in combination with a regulating circuit which is common to all of the control circuits, and includes temperature-dependent means for controlling the regulating means, whereby the latter supplies at its output a voltage which varies in accordance with the environmental temperature at such temperature-dependent means.

29 citations


Patent
18 Jun 1979
TL;DR: In this paper, the transducer converting current into a signal frequency has a threshold characteristic to insure a definite fixed signal frequency at very low currents, in order to counteract instability problems inherent in current controlled switching type voltage regulators.
Abstract: A current controlled switching type voltage regulator achieves voltage regulation by controlling an average current flow through the switching device. This current is sensed and transformed into a signal frequency. The signal frequency is counted to determine its average value and this count is compared to a variable current reference count which is continuously adjusted in response to an output voltage monitor which includes circuitry to generate an error count responsive to the deviation of the voltage output from a desired regulated value. In order to counteract instability problems inherent in current controlled switching type voltage regulators the transducer converting current into a signal frequency has a threshold characteristic to insure a definite fixed signal frequency at very low currents.

28 citations


Patent
Mitsuyuki Kiuchi1
21 Jun 1979
TL;DR: In this paper, an induction heating apparatus includes a DC power source, a transistor for generating a trigger current in response to a base drive pulse applied thereto, and a resonant load circuit including a work coil and a capacitor.
Abstract: An induction heating apparatus includes a DC power source, a transistor for generating a trigger current in response to a base drive pulse applied thereto, and a resonant load circuit including a work coil and a capacitor for generating in response to the trigger current an oscillating resonant current when the switching device is turned off, and which current is passed through a diode connected in inverse parallel relation with the transistor. A current transformer is provided to detect the load current. A low voltage detector senses a nearly zero voltage at the collector of the transistor and triggers a ramp generator to generate a ramp voltage which is compared with a reference voltage to generate a train of base drive pulses for application to the transistor. To control the base drive pulses at a variable duration in accordance with an inductive load, the reference voltage is varied as an inverse function of the sensed load current.

28 citations


Patent
29 Jun 1979
TL;DR: In this article, a power supply for generating a high unidirectional voltage at a charging electrode of an electrostatic spray coating apparatus has circuitry for sensing the magnitude of current flow to the electrode and for controlling application of an input voltage to the power supply in accordance therewith to control the high voltage.
Abstract: A power supply for generating a high unidirectional voltage at a charging electrode of an electrostatic spray coating apparatus has circuitry for sensing the magnitude of current flow to the electrode and for controlling application of an input voltage to the power supply in accordance therewith to control the magnitude of the high voltage. The arrangement is such that whenever the current flow is less than a predetermined value all cycles of the input voltage are applied to the power supply, but whenever the current exceeds the predetermined value only a limited number of the cycles are applied to the power supply. In this manner, the danger of arcing between the electrode and an article being coated is eliminated or at least significantly reduced.

Patent
31 Aug 1979
TL;DR: In this article, an integrated circuit system for generating a rise-time regulated and level controlled high voltage pulse utilizing a plurality of diode-connected stages driven by capacitively coupled low voltage clocks is presented.
Abstract: Integrated circuit system for generating a rise-time regulated and level controlled high voltage pulse utilizing a plurality of diode-connected stages driven by capacitively coupled low voltage clocks. The maximum output voltage may be controlled by a gated diode reference device, which provides a reference voltage independent of power supply voltage. A feedback circuit may be provided which controls the high voltage rise time by modulating the effective low voltage clock amplitude driving the high voltage generator. A MOS logic level interface circuit may also be provided for sensing achievement of the predetermined high voltage level.

Patent
06 Jul 1979
TL;DR: In this paper, a power control method and apparatus maintains a constant average power at an electrical load, such as a fuser in an electrophotocopy machine, and a power monitor measures the average power delivered to the load and compares the measured power to a predetermined power.
Abstract: A power control method and apparatus maintains a constant average power at an electrical load, such as a fuser in an electrophotocopy machine. A power monitor measures the average power delivered to the load and compares the measured power to a predetermined power. A digital network receives an input signal from the power monitor and controls the coupling of power from an ac source to the load. When load power is less than a predetermined level, the digital network couples every half cycle of the ac power source to the load. When the load power is equal to or greater than the predetermined power, the digital network couples every third ac half cycle to the load. As a result, only half cycles of sequentially opposite polarity are coupled to the load.

Patent
26 Feb 1979
TL;DR: In this paper, a substantially smooth, continuous and sinusoidal air gap flux signal for an AC machine is provided from machine terminal voltages and line currents, where a voltage representative of the machine stator voltage is combined with a voltage representing the resistive voltage drop component across the stator to yield an intermediate voltage.
Abstract: A substantially smooth, continuous and sinusoidal air gap flux signal for an AC machine is provided from machine terminal voltages and line currents. A voltage representative of the machine stator voltage is combined with a voltage representative of the resistive voltage drop component across the stator to yield an intermediate voltage. This intermediate voltage is integrated and combined with a voltage representative of the stator flux leakage reactance to yield an air gap flux signal proportional to the difference between the integral of the intermediate voltage and the stator flux leakage reactance voltage.

Patent
18 Jul 1979
TL;DR: In this article, a drive for a rotating field machine which has two AC voltage integrators of identical design for forming two electric voltage signals each of which is proportional to a flux component in the machine is described.
Abstract: A drive for a rotating field machine which has two AC voltage integrators of identical design for forming two electric voltage signals each of which is proportional to a flux component in the machine Each voltage integrator includes an integrator and a zero-controller having negative feedback for suppressing the DC component of input voltages fed to a summing point of the integrator Each integrator, is fed, as one input voltage, a voltage proportional to the phase-voltage belonging to the flux component and a voltage proportional to the corresponding stator current in a machine supply lead, for compensating the ohmic stator voltage drop A second voltage, also depending on the phase current, is processed to compensate for the inductive stator voltage drop To ensure optimum converter and machine utilization over an increased speed control range by reducing the phase errors of the determined flux components, each zero-controller includes a proportional controller and an integrated controller having output signals fed to the summing point The output signal of the integrator, corrected for the ohmic stator voltage drop and the inductive stray voltage, is fed, weighted proportionally to the frequency of the machine, to the input of the proportional controller, and weighted proportionally to the square of the frequency, to the input of the integrated controller, the weighting factor having a maximum value of 1

Patent
21 Feb 1979
TL;DR: In this article, a series pass voltage regulator compares the output voltage with a reference voltage and adjusts the base bias of a PNP series pass transistor coupled between an unregulated voltage source and a load to maintain a predetermined constant value.
Abstract: A series pass voltage regulator compares the output voltage with a reference voltage and adjusts the base bias of a PNP series pass transistor coupled between an unregulated voltage source and a load to maintain the output voltage at a predetermined constant value. A current sensing resistor senses the base current of the PNP series pass transistor and limits the base current to a predetermined value indicative of a maximum allowable load current.

Journal ArticleDOI
TL;DR: The reverse phase-controlled dimmer as mentioned in this paper uses a snubber capacitor in parallel with the main SCR's, which filters the output much like an inductor would, but without the inherent disadvantages.
Abstract: The reverse phase-controlled dimmer is an alternate method for varying the intensity of incandescent lights. Unlike conventional phase-controlled dimmers, the thyristors are triggered into conduction immediately following the zero crossing of the ac line rather than being delayed into the half-cycle. After an appropriate delay the silicon-controlled rectifiers (SCR's) are turned off by forced commutation. Manufacturers of conventional phase-controlled dimmers place a large inductor in series with the lamp load to reduce both lamp acoustical noise and radio-frequency interference (RFI) to acceptable levels. Instead of an inductor, reverse phase control connects a snubber capacitor in parallel with the main SCR's. The capacitor filters the output much like an inductor would, but without the inherent disadvantages. Eliminating the inductor makes more power available to the load since there is no reactive power loss in the main current path. Furthermore, without the inductor the dimmer will run quieter, because the inductor is a major source of acoustical noise. The control circuit incorporates an open loop scheme that provides line voltage regulation and fast response. A combination of analog and digital techniques tracks the amount of power available from the power line and meters out only the desired amount of the load. The dimmer responds to changes in control signal and line voltage within one half-cycle. Power levels are programmed by an 8 bit data word.

Patent
30 Apr 1979
TL;DR: In this article, two phase-locked loop (PLL) solid state devices are used in conjunction with a fiber optics transmitter-receiver link in order to derive at a remote location an analog signal which is a representation of an inputted analog signal.
Abstract: Two phase-locked loop (PLL) solid state devices are used in conjunction with a fiber optics transmitter-receiver link in order to derive at a remote location an analog signal which is a representation of an inputted analog signal. Frequency-modulation is used in an analog signal measurement context to provide a bandwidth extending from direct current to a frequency of the order of 125 kHz. The transmitter portion is integrated within the base enclosure of a high voltage coupling capacitor connected between a high voltage power line and ground to provide high voltage protection and measurement capability for high frequency high voltage transients or surges in relation to high voltage power lines from the remote location.

Journal ArticleDOI
TL;DR: In this paper, a method for the generation of a voltage equal to an integer multiple of the n-channel threshold voltage in c.m.o.s. integrated circuits is presented.
Abstract: A method is presented for the generation of a voltage equal to an integer multiple of the n-channel threshold voltage in c.m.o.s. integrated circuits. Experimental results from an integrated prototype are given and possible applications are discussed

Patent
30 Aug 1979
TL;DR: In this article, a switching regulator with an error amplifier and a current detector is presented. But the oscillator is changed from an ON state to an OFF state when the output of the error amplifier exceeds the input voltage.
Abstract: A switching regulator in which a DC input voltage is chopped by an oscillator applied to a transformer the output of which in turn is rectified by a rectifier circuit; a DC voltage derived from the rectifier is compared with a reference voltage so that a voltage is produced which corresponds to the deviation from said reference voltage of the aforementioned DC voltage derived from the rectifier; the voltage thus produced is amplified by means of an error amplifier; a current proportional to the transformer driving current provided by the oscillator is detected by a current detector; and the output of the error amplifier is compared with the output of the current detector so that only when the former exceeds the latter, a trigger signal is applied to the oscillator, whereby the oscillation of the oscillator is changed from an ON state to an OFF state. In such a switching regulator, there is provided circuitry for limiting the operation range of the aforementioned error amplifier by the difference between a voltage proportional to said DC voltage derived from the rectifier and a voltage proportional to the input voltage.

Patent
20 Feb 1979
TL;DR: Improved apparatus for discharging power from a high-voltage direct current line is presented in this paper, where a direct voltage convertor is connected in series with a smoothing filter and a DC high voltage line on one side and a second smoothing filtering and a power discharge inverter on the other side.
Abstract: Improved apparatus for discharging power from a high-voltage direct current line. A direct voltage convertor is connected in series with a smoothing filter and a DC high voltage line on one side and a second smoothing filter and a power discharge inverter on the other side. The rated voltage of the discharge inverter is substantially lower than the line voltage and the direct voltage convertor applies the lower voltage to the discharge inverter.

Patent
01 Oct 1979
TL;DR: In this paper, the sustaining current that maintains the latch in a regeneratively conducting state is derived from two voltage sources, with the current component derived from one of the two sources by itself insufficient to maintain the latch.
Abstract: A deflection generator develops scanning current in a horizontal deflection winding. A high voltage winding of a flyback transformer generates a high voltage for the picture tube ultor terminal. A high voltage safety circuit includes a flyback transformer secondary winding for applying a peak detected retrace pulse voltage to a disabling latch circuit. If the high voltage exceeds predetermined values, the latch is energized and disables normal operation of the deflection generator. Components of the sustaining current that maintains the latch in a regeneratively conducting state are derived from two voltage sources, with the current component derived from one of the two voltage sources by itself insufficient to maintain the latch in the regeneratively conducting state.

Patent
05 Jul 1979
TL;DR: In this paper, a semi-conductor voltage regulation system for a vehicle includes an engine rise-up detection circuit and an oscillator circuit, which is intermittently supplied by the oscillator before the engine starts and continuously supplied after the engine has started so as to minimize battery discharge.
Abstract: A semi-conductor voltage regulation system for a vehicle includes engine rise-up detection circuit and an oscillator circuit. The field exciting current is intermittently supplied by the oscillator circuit before the engine starts and continuously supplied after the engine has started so as to minimize battery discharge. The engine rise-up detection circuit changes its input impedance in accordance with the voltage applied thereto, whereby a highly reliable regulator with less heat generation may be obtained.

Patent
09 Feb 1979
TL;DR: A voltage control circuit for an uninterruptible power supply (UPS) involving a controlled rectifier operating from an input AC line to charge batteries and to hold them at a constant voltage is described in this paper.
Abstract: A voltage control circuit for an uninterruptible power supply (UPS), said UPS involving a controlled rectifier operating from an input AC line to charge batteries and to hold them at a constant voltage; the batteries supply power to an inverter which in turn produces an AC output, such output being uniquely controlled by efficiently and accurately compensating for any fluctuations due to battery voltage changes or to load changes.

Patent
31 Jul 1979
TL;DR: In this article, a low power dissipation power supply utilizes a chopper shunt voltage regulator operating to either direct current transformer developed charging current to storage capacitors when the supply voltage drops below a nominal level or to shunt charging current from the stored capacitors.
Abstract: A low power dissipation power supply utilizes a chopper shunt voltage regulator operating to either direct current transformer developed charging current to storage capacitors when the supply voltage drops below a nominal level or to shunt charging current from the storage capacitors when the supply voltage exceeds the nominal level. Switching of the regulator is controlled by the very small voltage ripple in the regulated supply voltage. In application to a circuit breaker static trip unit, the power supply is equipped to inhibit trip unit functions until the supply voltage is sufficiently up and to limit trip coil actuating current.

Patent
30 Nov 1979
TL;DR: In this paper, a direct current high voltage switching voltage regulator for generating a controlled low voltage, low current output referenced to the positive side of a variable voltage input voltage is provided.
Abstract: A direct current high voltage switching voltage regulator for generating a controlled low voltage, low current output referenced to the positive side of a variable voltage input voltage is provided while maintaining operation over an extended voltage input range with low power loss and heat dissipation and consequent high efficiency.

Patent
Edgar Kuhn1
27 Mar 1979
TL;DR: In this article, the authors proposed a compensation circuit for association with the regulator of an electrical generator, especially an AC generator, and serving to smooth the voltage supplied by the electric generator.
Abstract: Being proposed is a circuit for association with the regulator of an electrical generator, especially an AC generator, and serving to smooth the voltage supplied by the electric generator. The circuit includes a compensation device consisting of at least one active semiconductor switching element, usually a transistor, and so connected to the regulator input as a supplement thereto that the generator output voltage is smoothed by a compensation voltage whose own ripple or oscillatory component is in opposite phase to the generator voltage. In particular, the compensation circuit includes a voltage divider connected to the generator output voltage and having a tap which is connected via a capacitor to the control electrode of the transistor whose main conducting path is connected in parallel to a further voltage divider joined to receive the generator voltage as well as to supply the input voltage to the regulator.

Patent
29 May 1979
TL;DR: In this article, a push-pull output stage self-oscillates as an astable multivibrator to develop the AC supply voltage within a start-up interval.
Abstract: A horizontal oscillator provides switching signals for use by a trace switch of a horizontal deflection circuit and to drive a push-pull output stage. The push-pull output stage provides an AC supply voltage to the primary of a power transformer. The rectified secondary winding voltage of the transformer provides a B+ supply voltage to the deflection circuit. After the elapse of a start-up interval, energization voltage for the horizontal oscillator is provided by either the power transformer or the deflection circuit. During the start-up interval the push-pull output stage self-oscillates as an astable multivibrator to develop the AC supply voltage within that interval.

Patent
30 Oct 1979
TL;DR: In this paper, a highvoltage crowbar circuit continually senses the load impedance and crowbars the output voltage applied to a load if the load's impedance falls below a selected value, and a differentiator circuit at the load senses variations in load voltage and can trigger the crowbar operation.
Abstract: A high-voltage crowbar circuit continually senses the load impedance and crowbars the output voltage applied to a load if the load impedance falls below a selected value. A differentiator circuit at the load senses variations in load voltage and can trigger the crowbar operation if the voltage variation as a function of time exceeds a preselected load.

Journal ArticleDOI
TL;DR: In this article, a theoretical basis for analyzing the converters which serve to minimize the effects of pulsed power and corresponding reactive volt-amperes is provided, at a readily controllable rate including the reversibility of power in case of inductive loads.
Abstract: There is a growing need for supplying repetitive pulsed power loads of increasing magnitudes up to several hundred megawatts or more in areas of radar, lasers, high-energy physics experiments and thermonuclear fusion. The nature of such loads can be expected to be as diverse as their applications. The pulsed power demands and corresponding reactive volt-amperes requirements are undesirable from the frequency and voltage fluctuation standpoint, even for the large utility power systems. Techniques for supplying large dc-pulsed loads from a relatively small size ac generator by means of inductive storage and the capacitor commutated converters are presented. A theoretical basis is provided for analyzing the converters which serve to minimize the effects of pulsed power and corresponding reactive volt-amperes. Energy transfer between the storage inductor and the pulsed load is permitted with minimal loss, at a readily controllable rate including the reversibility of power in case of inductive loads. Use of a simple control scheme is shown to provide a precise load voltage regulation which may be a requirement for certain applications. The greatest use of these circuits would be in supplying loads with pulse durations of a few milliseconds to many seconds or minutes.