Showing papers on "Voltage regulation published in 1978"

A Calculation Method for Impulse Voltage Distribution and Transferred Voltage in Transformer Windings

Abstract: This paper presents a calculation method for impulse voltage distribution in the complex winding arrangement encountered in large power transformers. This method takes into account the electrostatic and electromagnetic combinations of windings, and, therefore, permits a precise analysis of voltage response in the windings to which an impulse voltage is applied and of the transferred voltage in other windings to which an impulse voltage is not applied directly.

Impact of Voltage Reduction on Energy and Demand

Abstract: This paper reports the results of an experimental investigation concerning the impact of voltage reduction on the energy use and demand level as it relates to load composition, specifically that of the American Electric Power System.

Low voltage techniques

Abstract: Techniques for the design of linear ICs, capable of operating from a single nickel-cadmium cell (> 1.1V) will be presented. Results can be achieved without compromising performance or operation at higher voltages. Emphasis will be on micropower, though not at the expense of output drive.

High frequency voltage generator

Abstract: This high frequency voltage generator which may be used particularly in surgery for supplying an electric bistoury, comprises a power oscillator operating an output transformer. A chopping supply is placed in the direct control chain of the power oscillator. The output voltage of the generator is controlled by a first regulation loop whose reference value is increased by means of a positive feedback proportional to the output current.

Application of a Static VAR System to Regulate System Voltage in Western Nebraska

Abstract: Basin Electric Power Cooperative will commission a Static Var System (SVS) in late 1977 to provide automatic, continuous voltage control on a 115 kV network in western Nebraska. This paper describes engineering studies which were conducted to select the SVS rating and site, determine harmonic filtering requirements, synthesize the SVS voltage regulator characteristics and to simulate the steady-state and dynamic performance of the SVS. The studies have shown that the SVS will perform as intended to regulate the steady-state voltage within ±0.5% and reduce post-fault voltage swings which otherwise might cause important motor loads to trip off line.

Dynamic current balancing for power converters

Abstract: A current balance arrangement for the power switching devices of a push-pull converter circuit is disclosed. A dynamic dead band circuit is incorporated into a pulse width modulation current balance and output voltage regulation control circuit to prevent current imbalance from causing saturation of the power transformer core for all operating conditions of the converter including input voltage falling below its rated low-line value, sudden load surges, or turning off of the converter power supply. Whenever the dynamic dead band circuit determines that inverter current flow is being terminated by the dead band interval of the converter clock, a control signal is sent to the pulse width modulation circuitry of the converter to effect inverter current termination prior to initiation of the clock dead band interval in subsequent cycles of converter operation. The invention eliminates the need for providing inverter power switching devices having closely matched electrical characteristics.

Regulated switching mode power supply

Abstract: A switching mode power supply characterized by an output in the forward conversion mode and a separate output in the flyback mode whereby a device having variable power requirements in one aspect of its operation, and a stable power requirement another aspect of its operation may be powered without interference as between the two sources of power. The flyback power output is monitored for voltage regulation, regulation being achieved by a constant-off-time variable-on-time switch. The power supply likewise includes novel protective circuitry to shut it down in the event of excessive voltage or current therein.

Regulated high voltage power supply

Abstract: In a voltage supply wherein a voltage multiplier produces an output voltage level in proportion to its driving frequency, the output voltage level is regulated by incorporating a voltage controlled oscillator to vary the driving frequency in accordance with the output voltage level of the voltage multiplier. To improve operating efficiency, current amplifiers are disposed between the output of the voltage control oscillator and the input of the voltage multiplier. Furthermore, a level shift means is incorporated in another embodiment for disabling the voltage controlled oscillator and for impressing a rail voltage level at the output terminal of the voltage multiplier.

Method and apparatus for conserving energy

Abstract: A method and apparatus for regulating the luminous flux generated by a lamp with the degeneration of the voltage from a power source such as a battery. The regulating circuit maintains a constant luminous flux output from a lamp over a substantial range of voltages by switching the voltage to the lamp on and off at a preselected and controlled duty cycle. The principal advantage of this regulation is that only the minimum energy necessary to produce a required minimum luminous flux is used from the power sources irrespective of its voltage value within the operative range. The power pulses applied to the lamp are of a voltage that varies directly as the voltage variations of the power source and widths that vary as the inverse square of the voltage from the power source for maintaining a constant RMS voltage on the lamp and thereby constant light output flux. The oscillating signal generator for providing the power pulses is defined for sensing the power source output voltage variations and generates a fixed frequency signal having amplitudes varying between values directly related to the power source output voltages.

Digital electric energy measuring circuit

Abstract: A digital electric energy measuring circuit for totalizing electrical power and energy usage from an alternating current supply by converting a voltage signal representing the current component into a pulse train signal whose frequency is proportional to the magnitude of the voltage, sampling that frequency to provide a digital value representing the current component, and then converting a voltage signal representing the voltage component into a second pulse train signal whose frequency is proportional to the magnitude of the voltage which is used to control the rate that the digitized value of the current component is successively added which provides an indication of electrical energy that is totalized and displayed

Voltage conversion system for electronic timepiece

Abstract: A voltage conversion system for an electronic timepiece having a power source, which system generates power at lower voltage level than that of the power source for operating at least one of a frequency standard, a frequency converter, a time counter circuit and a display system. The voltage conversion system comprises an oscillator circuit coupled to the power source to generate output signals, a plurality of capacitors, and a plurality of switching elements responsive to the output signals for alternately setting the capacitors in a parallel connected condition and a series connected condition, whereby an output voltage lower than that of the power source is generated at an output terminal of the system.

Active filter circuit for regulated dc to dc power supplies

Abstract: A regulated DC to DC power supply which minimizes input bus current changes caused by low frequency cyclical load variations is disclosed. The power supply includes a regulator connected to the input bus and controlled by a pulse width modulator. The regulator converts the DC voltage on the input bus to a higher, regulated DC voltage which is supplied to a variable load. A voltage feedback circuit is connected to the output of the boost converter and generates a control voltage which is supplied to the pulse width modulator to regulate the output voltage for variations in line voltage and load. The voltage feedback circuit includes an operational amplifier having a reference voltage supplied to a positive input terminal, and the output of the regulator supplied to a negative input terminal. A frequency response shaping network is connected between the output and the negative input terminal of the operational amplifier. An input bus current-sensing servo circuit is connected to sense current variations in the input bus and generate a control signal to the pulse width modulator to regulate the input current of the regulator. The input bus current-sensing servo circuit also includes an operational amplifier and an RC frequency response shaping network. The two frequency response shaping networks are designed such that, for a variable load which exhibits a given low frequency cyclical power change, the voltage feedback circuit generates a control signal for voltage variations below the given low frequency, but the input bus current-sensing servo circuit generates a control signal for changes having a predetermined frequency range including the given low frequency.

Selectively adjustable voltage detection integrated circuit

Abstract: A voltage detection integrated circuit including a voltage regulation circuit for controlling the operation thereof is provided. The voltage detection integrated circuit includes a reference voltage circuit for producing a predetermined reference voltage, a voltage converter for converting a detected voltage for measurement and a comparator circuit for comparing the level of the reference voltage to the level of the converted voltage and for producing a comparison signal representative of the difference in voltage levels compared thereby. The voltage regulation circuit is coupled to the comparator circuit and the reference voltage circuit and/or voltage conversion circuit for selectively adjusting the level of the reference voltage produced by the reference voltage circuit and/or the converted voltage produced by the voltage converter, to thereby control the comparison signal produced by the comparator circuit.

Voltage dropping circuit

Abstract: This invention provides a voltage dropping circuit which is composed of capacitors and MOS field effect electronic switching elements whereby a voltage equal to M/N of the voltage of a power source is obtained.

Influence of Generator Capability Curves Representation on System Voltage and Reactive Power Control Studies

Abstract: The influence of generator capability chart representation (overexcited zone) on system voltage and reactive power control studies is examined. A load pick-up in a power system is simulated by means of a computer program and the steady--state operation in some "critical" conditions (heavy power flows and low power factors) is analyzed. Under these conditions the adoption of the simplified representation (rectangular) or of a more exact representation of the actual capability charts, may influence the search for feasible solutions to a considerable extent. Possible criteria for the optimization of system voltage and reactive power scheduling in critical conditions are also discussed on the basis of this more L exact representation.

Defibrillator charging current regulator

Abstract: The capacitor of a defibrillator is charged to a high D.C. voltage from a low voltage D.C. source of small capacity by an inverter, a transformer, and a rectifier coupled in sequence. The turns ratio of the transformer is changed as the voltage across the capacitor reaches predetermined levels and the current in the primary of the transformer is regulated by comparing the voltage drop across a small resistor with the voltage of the source.

Voltage regulator utilizing a static var generator with half period averaging and saturating type firing angle control

Abstract: 47,479 VOLTAGE REGULATOR UTILIZING A STATIC VAR GENERATOR WITH HALF PERIOD AVERAGING AND SATURATING TYPE FIRING ANGLE CONTROL ABSTRACT OF THE DISCLOSURE A voltage regulator is taught for maintaining the terminal voltage of a three phase transmission line at a fixed reference value. The voltage regulator system utilizes the reactance of the transmission line in conjunction with reactive current from a VAR generator to compensate for the voltage effect of line current as it flows through the line reactance. me VAR generator is of the parallel capacitor-inductor type where the inductor is controlled by a thyristor switch. The conduction of the thyristor is controlled by utilizing a control system which generates an error signal based on the half period average of line voltage. The error signal is converted to a signal which is proportional to flux linkages by an integrator and then compared with the integral of the voltage signal for determining the conduc-tion angle of the thyristor switches.

Power supply for an electric precipitator

Abstract: An improved power supply for an electric precipitator which includes a d-c voltage source and a pulsed a-c voltage source coupled to the high-voltage electrodes of the precipitator. The improvement of the invention comprises the pulsed a-c voltage source comprising a high-voltage transformer including a primary winding and a secondary winding, the latter of which is coupled to the high-voltage electrodes of the precipitator. A d-c voltage source has one of the voltage terminals thereof coupled by means of a center tap to the primary winding of the transformer and the other of its voltage terminals coupled to a pair of thyristors and a pair of diodes connected to the ends of the primary winding of the transformer. The thyristors are coupled in anti-parallel relationship with the diodes and are adapted to be triggered in alternating fashion at the frequency of the voltage pulses desired to be generated.

RMS Circuit for voltage regulation

Abstract: A circuit for providing a signal proportional to the RMS value of a periodic input waveform having either a variable or fixed frequency. The input waveform is applied to a rectifier. The output from the rectifier is squared and integrated at least once each period of the periodic waveform. The integrated voltage is sampled and a voltage equal to the sampled voltage is applied to a divider circuit. The output of the divider circuit is applied to a square root circuit until the integrated voltage is again sampled, at which time the voltage provided to the square root circuit is updated. The output from the square root circuit is a voltage proportional to the RMS value of the input waveform. The circuit can be coupled to an AC generator to provide RMS regulation of the AC voltage wherein the voltage proportional to the RMS value of the input waveform is applied to the exciter winding of the generator for control thereof.

Method for regulating the voltage of an electric generator and a system for the application of said method

Abstract: The method for regulating the terminal voltage delivered by an independent alternating-current generator consists in measuring the voltage in at least one phase, in measuring and automatically adjusting the frequency with respect to a reference value by putting dissipative resistors in circuit, and in automatically varying the reference value of the frequency as a function of variations in voltage. The invention achieves stable voltage control which prevents harmful oscillations and is applicable in particular to asynchronous generators which are driven by a natural fluid.

MOS Control circuit for integrated circuits

Abstract: A circuit arrangement includes a MOS field effect transistor as a variable resistance in series with a load such as an integrated circuit across a power supply with means for controlling the variable resistance to establish a very constant supply or input voltage to the load. A switch may be included to apply a constant supply or input voltage of different known values to a load such as an oscillator requiring different voltages at different stages of operation.

Apparatus and method for regulating the power factor in an electrical distributing-network line

Abstract: The specification discloses an apparatus and a method for regulating the power factor in an electrical distributing-network line; according to one embodiment of the invention, the active line power is measured by means of a transducer, the output from which is a continuous voltage proportional to the active power supplied by the line; the reactive power of the line is then measured by means of a second transducer, the output from which is also a continuous voltage proportional to the reactive power supplied by the line; the voltage supplied by the active-power transducer is then divided by voltage dividers in order to obtain two reference voltages L 1 , L 2 , the values of which indicate the fixed limits for the line power factor; the voltage supplied by the reactive-power transducer is then compared with reference voltages L 1 , L 2 for the purpose of obtaining two logic levels indicating one of the three following operations: one or more capacitors are connected if the power factor is below the limit L 1 and is inductive; one or more capacitors are disconnected if the power factor is above the limit L 2 and is inductive; no action is taken if the power factor is above the limit L 1 and below the limit L 2 and is inductive.

Method and apparatus for measuring the insulation resistance of an operating grounded transmission line system

Abstract: By introducing a secondary voltage having a lower frequency than the principal voltage in a grounded transmission line system, detecting the current arising from such secondary voltage only and multiplying such current by the magnitude of the secondary voltage a resultant signal is obtained which is proportional to the inverse of the insulation resistance of the system.

Regulated dual DC power supply

Abstract: A dual section power supply, one section for supplying high voltage dc po and the other section for supplying low voltage dc power, are each connected to a common ac source. The high voltage section employs a phase-controlled rectifier, the control circuit for which employs logic signal development using timer techniques dependent on the amplitude of voltage deviation from the intended regulated output level. Each of two low voltage sections employs a power switch controlled by sampling and pulse steering techniques to effect fixed high frequency, variable duty cycle switching. An inhibit input is supplied from each of the low voltage sections to the high voltage section to prevent a high voltage output to the load in the absence of low voltage development.

Voltage power supply

Abstract: A voltage power supply, particularly one which is especially suitable for providing a relatively high DC voltage output of rapidly changing amplitude adapted to drive a cathode ray tube (CRT), is disclosed herein. This voltage supply includes circuitry adapted for connection to a relatively low amplitude (actually magnitude) DC voltage input for first converting this input to an AC voltage output and then converting the AC voltage output to a DC drive voltage having a fixed amplitude substantially higher than the DC voltage input. This higher amplitude DC voltage is applied to voltage varying circuitry, specifically a pullup and pulldown circuit arrangement, for producing at its output an adjustable DC output voltage having an amplitude which does not exceed the amplitude of the drive voltage. A voltage adjusting circuit is connected to this latter circuit arrangement and is also adapted for connection to a coded signal for rapidly changing the amplitude of the adjustable output voltage in response thereto.

Avoidance of hot electron operation of voltage stressed bootstrap drivers

Abstract: An improved field effect transistor circuit adapted to operate at high switching speeds and to avoid hot electron operation of voltage stressed FET bootstrap drivers. The circuit comprises a voltage control means adapted to maintain a simultaneous gate and drain to source voltage of FET devices within a characteristic hot electron operational voltage range. The voltage control means is adapted to reduce FET drain to source voltage by connecting a plurality of FET devices in series to reduce the drain to source voltage drop across each device. The drain to source voltage is further defined by connecting the common nodes of successive series connected devices to a specified voltage source that is less than a characteristic hot electron drain to source voltage. The voltage control means also includes a gate voltage clamping FET that is adapted to hold down the gate of a device when the drain to source voltage of the device rises above a particular hot electron voltage. The voltage control means further comprises a plurality of timing pulses that define particular combinations of gate and drain to source device voltages that are less than characteristic combined hot electron voltages. The voltage control means further includes devices with width to length ratios adapted to provide close voltage tracking between input drain voltages and output source voltages to maintain a minimum drain to source voltage drop. The operation of the hot electron voltage control means is particularly described with respect to embodiments using voltage stressed bootstrap driver FETs to generate on chip clock phases.

Pulse transformer technique for optical switch

Abstract: Optical communication apparatus is disclosed whereby the voltage controlled load device typically requiring a relatively high energizing voltage is operated by means of a wide band step-up pulse transformer and a low voltage power source. The step-up transformer permits operation of the fiber optic communication system from a power source as low as 5 volts D.C. to obtain the necessary modulation potential required by the electro-optic and piezoelectric load device.

High frequency high voltage power supply

Abstract: A compact and lightweight power supply particularly suited for use as a high voltage supply capable of switching voltage values in short time. The high voltage output is compared against a desired reference value to produce a difference voltage which is integrated. The integrated difference voltage is converted to recurrent pulses having a corresponding width. The pulses are applied alternately to the opposite ends of a centertapped primary winding of a specially wound transformer characterized by a specially wound secondary winding and an air-gapped E-shaped core linking the primary and secondary windings. The secondary voltage is applied to a voltage multiplier circuit to produce the high voltage output of the power supply.

Sound volume controller

Abstract: PURPOSE:To ensure the perfect sound arrest at the remote control time by applying the voltage which conducts when the control voltage is under the fixed level to the base side of the transistor connected to the control terminal of the electronic volume circuit. CONSTITUTION:Electronic volume circuit 6 varies the sound volume by the control voltage which is applied to the control terminal and then generates the control voltage via control voltage generation cirucit 1 featuring such characteristics as to become the minimum voltage under the sound arrest control state to apply it to circuit 6. Then the collector and the emitter are connected between the control terminal and the earth of circuit 6 via transistor 15, and the voltage is applied to the base side so that the conduction may be secured when the control voltage becomes under the fixed voltage level. As a result, the impedance of the supply path of the control voltage can be reduced at one time in the range where the sound volume is small, and also the sound arresting function can be secured well at the remote control time to perform the perfect sound arrest.

Signal ratio indicator

Abstract: A pressure measuring system which includes a variable reluctance pressure transducer energized from an alternating voltage source, wherein the ratio of the output voltage to the source voltage is proportional to the pressure being sensed. Precision full wave rectifiers convert the source and output voltages to reference and sensing direct voltage signals, respectively. A switching regulator regulates the higher amplitude reference voltage signal to have exactly the same average voltage as the sensing voltage signal. The switching regulator also regulates a constant voltage DC signal from a regulated power supply at the same switching duty cycle as the regulated reference voltage signal, to produce a direct voltage, pressure-sensing signal which is uneffected by voltage fluctuations in the alternating voltage source for the pressure transducer. After the DC offset corresponding to the lowest pressure difference to be measured is removed, this direct voltage, pressure-sensing signal is converted to a direct current signal to drive a DC ammeter, calibrated in units of pressure, which is connected to an unregulated DC power supply.