Showing papers on "Voltage regulator published in 1975"

Voltage regulator for TV receiver line output stage - has booster diode with transducer as variable regulating impedance

Abstract: The supply voltage regulator, for a television receiver's line output stage, has a transductor as variable impedance to regulate and stabilise the supply voltage. The transductor is connected by one half between the input supply and over a booster diode to the line transformer, and by the other half between +24V and its control voltage. The control voltage is derived from the line transformer's booster capacitor. This regulating method is only possible for output stages with voltage or IV feedback and with booster diodes carrying supply-current pulses; it cannot be used with output stages that are supplied directly with pure d.c. currents.

Voltage regulator tester

Abstract: A test circuit for automotive voltage regulators includes means for simulating transient battery voltages, a meter for monitoring these voltages as related to the operation of the regulator being tested, switching means to protect the meter and also to facilitate the reading thereof, a test load simulating the field coil of an automotive alternator, and an indicator light for determining when the test load is energized. The volt meter indicator moves to show increasing voltage and returns to zero when the regulator interrupts the current to the test load.

Multiple winding multiple voltage alternator electrical supply system

Abstract: A multiple voltage electrical supply system continuously connected for individually charging a plurality of battery supplies continuously connected in series with one another to supply a plurality of load circuits having differing d.c. input voltage requirements and, typically, also having differing expected electrical power consumption rates. The system includes an alternator having electrically isolated generating windings disposed so as to insure that the magnetic flux linking each of the generating windings bears a substantially constant ratio to that linking the other of the generating windings. The exemplary embodiment has generating windings of different characteristic resistance per unit length such that there is an increased internal voltage drop in the winding intended to supply the lighter electrical load. The resultant voltage regulation characteristics are such that a single voltage regulator is sufficient to maintain both of the output voltages at a substantially constant predetermined ratio.

Solar cooling system for an automobile

Abstract: A solar energy cell system is used as an electric supply source to operate an air conditioner or a fan ventilation system contained within the interior chamber of an automobile. The electrical circuit comprises a series circuit consisting of: the solar energy cells, a voltage regulator, a storage battery, a thermostatic temperature control and a ventilation fan or an automobile air conditioner.

Pulse width modulated voltage regulator-converter/power converter having push-push regulator-converter means

Abstract: Disclosed herein is an improved pulse width modulated (PWM) voltage regulator-converter system which can function, alone, as a switched voltage regulator system or in combination with a switched power converter, synchronized therewith to form an improved voltage regulator-converter/power converter system. In the pulse width modulated voltage regulator-converter embodiment of the invention, secondary windings of a "current mode" regulator-converter interstage transformer are coupled to regulator-converter power transistors in a push-push circuit configuration. Signals generated by a system clock means and an error signal, derived from the output of an averaging filter, drive a pulse width modulated control means connected to the primary windings of the regulator-converter interstage transformer to thereby increase the maximum regulated output voltage of the voltage regulator-converter system after conditioning in the averaging filter. In the pulse width modulated voltage regulator-converter/power converter embodiment of the invention, the aforementioned output voltage of the voltage regulator-converter system is coupled directly to a switched power converter connected in a push-pull circuit configuration. In turn, additional signals generated by the system clock means switch the power converter in synchronizm with the voltage regulator-converter system.

Pulse width modulated voltage regulator-converter/power converter having means for improving the static stability characteristics thereof

Abstract: Instability effects over a wide range of static load current conditions in a conventional pulse width modulated (PWM) voltage regulator-converter/power converter circuit configuration having cascaded LC--LC filter networks are eliminated by replacing an inductor, in the averaging filter section of the voltage regulator-converter with the primary winding of a transinductor and by placing the secondary winding thereof in series with an inductor in the output filter section of the power converter. The aforementioned transinductor, in combination with other elements of the system, is designed and configurated such that the closed-loop stability characteristics approach that of a two pole system while maintaining the superior filtering characteristics of a four pole system.

Vehicle with regenerative power system

Abstract: A wheeled vehicle is provided including a main frame having a plurality of ground engageable support wheels. An electric motor is supported from the main frame and drive train structure drivingly connects the rotatable output shaft of the motor to at least one of the ground engaging support wheels. A bank of rechargeable storage batteries is also supported from the main frame and electrically connected to the motor for actuation thereof through a variable voltage control. Also, a pair of generators or alternators are supported from the main frame and are driven from at least one of the ground engaging support wheels of the vehicle. The generators or alternators are electrically connected to the bank of storage batteries for recharging the latter. At least one of the generators is electrically connected to the bank of storage batteries through a voltage regulator and the circuit electrically connecting the other generator or alternator to the bank of storage batteries may include a control switch actuated to a closed position upon initial depression of the brake pedal of the associated vehicle. It is intended that the generators or alternators will be used to partially recharge the bank of batteries when the vehicle is coasting to a stop or coasting downhill.

Dual battery charge control

Abstract: Two series-connected batteries are connected across the power and ground terminals of an alternator and a silicon controlled rectifier selectively connects said power terminal to the junction between the batteries. A turn-on control circuit for the silicon controlled rectifier is connected across the battery providing the higher voltage output to effect conduction of the silicon controlled rectifier when the voltage drop across said battery reaches a predetermined value, whereby to direct charging current from the alternator only through the battery providing the lower voltage output. A turn-off control circuit for the silicon controlled rectifier also may be provided to connect the series batteries to the power input of a voltage regulator to effect deactivation of the alternator and silicon controlled rectifier when the voltage drop across the higher voltage output battery decreases a predetermined amount with respect to the voltage drop across the lower voltage output battery, the turn-off control circuit also functioning to activate the voltage regulator, alternator and silicon control rectifier when the voltage across the lower voltage output battery starts to drop, thereby re-establishing charging through both batteries.

Alternator-rectifier unit with phase winding and rectifier sets subject to series-parallel switching

Abstract: Separate three-phase windings are connected to individual rectifiers arranged for series-parallel switching to improve the current-voltage output characteristic. The common exciter winding is fed through a voltage regulator. The switching of the rectifiers is controllable in response to alternator frequency, output current, temperature or efficiency and may be provided with a manual override switch.

Semiconductor memory structures

Abstract: A method of storing electric charges in a metal-nitride-oxide-semiconductor memory element by setting the threshold voltage of the element at any of a substantial number of voltages by applying both a DC voltage corresponding to the analog voltage to be stored and an AC voltage which is gradually reduced.

Power supply for a laser or gas discharge lamp

Abstract: A regulated power supply for a laser or gas discharge lamp employs a variable duty cycle oscillator to control the output voltage level. Output current to the laser or lamp load is maintained at a constant value by a feedback loop that controls the oscillator duty cycle. The output current is sensed by a novel circuit which employs a voltage regulator in series with the current return path. A change in output current causes a concomitant change in voltage across a resistor divider that shunts the voltage regulator. The voltage from this divider is a feedback signal that is supplied to a duty cycle modulator which controls the oscillator duty cycle. Another feedback signal is derived in delayed response to voltage output in excess of a certain high value. This feedback signal, which occurs, e.g., when the laser or lamp load does not ignite within a certain time period, also modifies the oscillator duty cycle so as to reduce the output voltage to a level that can be maintained continuously without damage or overheating of any circuit component.

Phase-controlled voltage regulator

Abstract: A method and apparatus for regulating the RMS voltage applied to a load from an AC source having a peak-to-peak amplitude which varies within a predefined range. The apparatus comprises a waveform generator for producing a predefined periodic waveform, a comparator circuit for comparing such waveform with the sinusoidal waveform of the source whereby a signal is produced each time the algebraic difference between the instantaneous values of the compared waveforms changes sign, and a switching circuit responsive to the comparator circuit output for interrupting the voltage applied to the load at the start of each cycle or half-cycle. The shape of the waveform produced by the waveform generator is such that the desired RMS voltage appearing at the output terminals is produced.

Method of determining the driver's sufficient alertness to drive a motor vehicle safely

Abstract: A constant voltage developed by a constant voltage generator is integrated, and the integrated voltage is applied to a voltage comparator. A standard voltage is applied to a voltage controller, which includes a sensor responsive to vehicle operating conditions, to control the level of the standard voltage to indicate the degree of driver alertness necessitated by the vehicle operatingconditions. The controlled standard voltage is also applied to the voltage comparator, and when the integrated voltage exceeds the controlled standard voltage the comparator develops a warning signal output. A warning device receives the warning signal and is thereby rendered operative in order to alert the driver.

Device for non-invasive programming of implanted body stimulators

Abstract: A device for the non-invasive programming of an implantable body stimulator. The device includes a power supply and circuitry for generating and transmitting a preselected number of pulses of radio frequency energy. A push-button switch initiates the operation of the pulse-generating circuitry and the power supply is enabled only during an interval of predetermined duration following the initiating of operation of the pulse-generating circuitry. In a preferred embodiment, the power supply includes a power source, such as batteries, and a voltage regulator for establishing a substantially constant supply voltage for all power source voltages above a preselected level. The device may include circuitry for indicating the establishment of the substantially constant supply voltage as well as circuitry for preventing the transmission of any programming pulses upon a failure to establish the substantially constant supply voltage level. The transmitted pulses may be employed to alter an output parameter of any implanted body stimulator and is described with reference to an alteration in the repetition rate of an implanted cardiac pacemaker.

Dc to ac inverter with unregulated input and regulated output

Abstract: An inverter for producing regulated AC voltage from an unregulated DC voltage source, such as a battery, employs two stepped voltage waveform generating means independently controlled in phase to produce waveform outputs that approach sine waves which are additively combined to produce an AC output voltage whose amplitude is sensed to produce a feedback signal for comparison with a reference voltage to produce an error signal that causes one stepped waveform generating means to so shift in phase relative to the other as to reduce the error. Each stepped voltage waveform generating means is capable of producing at least half the total desired AC output voltage, so that the DC voltage source may drop by as much as 50% and the desired AC output voltage can still be maintained by shifting the relative phase between the stepped waveforms.

Integrated circuit having internal main supply voltage regulator

Abstract: A complementary field effect transistor integrated circuit includes an input buffer, internal high density logic circuitry having a collapsed guard ring structure associated therewith, an internal power source which provides operating voltage for the internal high density logic lower than the junction reverse breakdown voltage of the collapsed guard ring structure, and an output level shifter circuit. The output level shifter circuit and input buffer, and internal power source have a conventional non-collapsed guard ring structure associated therewith.

Constant power regulator for xerographic fusing system

Abstract: A constant power regulator for a xerographic fuser in which power control is achieved by taking the sum of the load voltage and current. The regulator includes an operational amplifier connected as a voltage adding circuit. The operational circuit amplifier of the power regulator adds the voltage drop across the fuser and a reference resistor connected in series with the fuser and the voltage drop across the fixed reference resistance which represents the current flow through the fuser. The output of this summing circuit is detected by a photodetector that electrically isolates the power regulator from a voltage regulator which has an output for controlling the power supply to the fuser through, for example, a triac, controlled as a function of the power supply signal and the detected voltage generated by the power regulating circuit.

Circuit for low power-low energy source

Abstract: A DC to DC converter with voltage regulator for converting a low level voltage source to a higher level DC, comprising an oscillator circuit with a low resistance starting current path, a rectifier circuit for rectifying the oscillator output, and a regulator for providing a regulated DC output voltage of predetermined level. The oscillator embodies one or more FET devices connected to provide an extremely low DC startup resistance as well as a low cutoff voltage characteristic. With this configuration, the low startup current from the voltage source can initiate switching so that oscillation can occur.

Battery checker circuit

Abstract: A battery checker circuit comprises a voltage divider connected across a storage battery and including a voltage detection resistor. The voltage developed across the detection resistor is sensed by a transistor, which conducts to energize a display element when the battery voltage is above a reference voltage. For a battery voltage below the reference voltage, the transistor is rendered nonconductive to deenergize the display element. The illumination or extinction of the display element indicates whether the battery voltage is above or below the reference voltage.

High speed, step-switching AC line voltage regulator with half-cycle step response

Abstract: An AC line voltage regulator having a cross-coupled memory circuit that interlocks up and down counter logic channels in a manner that successive stepping in the same direction is accomplished in half-cycle steps, while oscillatory stepping between two adjacent ranges is limited to full cycle steps to prevent any DC component in the regulated output. An alternate circuit uses a dual gating circuit in a bi-directional counter to achieve the same regulation characteristics.

Automatic V-I crossover regulator

Abstract: In order to achieve the capability to operate a plurality of identical power supplies in parallel, whereby the drawbacks of the conventional master-slave regulator relationship are avoided, the regulator of each power supply is provided with a load current sensor and a secondary differential amplifier circuit responsive to a predetermined load current for controlling the normal reference voltage supplied to the primary, voltage regulating differential amplifier. As a result of the inevitable, within-tolerance differences in the characteristics of two paralleled regulators, one supply will assume constant current operation at the predetermined load current while the other supply will operate at constant voltage and will carry the remainder of the actual load current. As many identical power supplies as necessary for a given application may be operated in parallel, and a single one will automatically operate in the constant voltage mode while the rest operate in the constant current mode.

Dual battery charging generator system

Abstract: A battery charging generator which is capable of charging two series connected batteries in a motor vehicle electrical system where the series connected batteries are used to energize the cranking motor of a motor vehicle. The generator is of the alternating current type and has first and second three-phase full-wave bridge rectifier units built into the end frame of the generator each of which is capable of supplying charging current to one of the batteries. The generator has a built-in transistor voltage regulator which senses the voltage applied to the main battery of the system by the first bridge rectifier and which regulates the output voltage of the generator to a predetermined value. The second bridge rectifier supplies charging current to an auxiliary battery and is connected with the stator winding of the alternating current generator by means of a three-phase transformer. The transformer, like the bridge rectifiers, is built into the end frame of the generator and isolates the two bridge rectifiers of the system. The generator is arranged with a 12 volt and a 24 volt output terminal which only need be connected directly to the batteries when installing a generator on a motor vehicle.

Controlled reactance regulator circuit

Abstract: A circuit for providing a regulated a-c or d-c output voltage from an unregulated a-c input voltage. A series inductance is connected between the regulator input and the regulator output to support the difference in voltage between the unregulated a-c input voltage and the regulated a-c or d-c output voltage. A controllable shunt reactance is connected to the source of input voltage, through the series inductance, to vary the current through and the voltage across the series inductance. Control circuitry controls the magnitude and the capacitive/inductive character of the current which the shunt reactance draws through the line inductance, as required, to establish and maintain the regulated output voltage at the desired output current.

Programmable shunt voltage regulator circuit

Abstract: A shunt regulator circuit having a reference voltage generator in which the collector currents of a pair of transistors are adjusted by the ratios of their load resistances to produce a temperature coefficient equal and opposite to the temperature coefficient of third transistor; a proportional sample of the output voltage is compared to the temperature stable reference voltage to adjust the shunt current to maintain the output voltage constant.

System performance characteristics of superconducting alternators for electric utility power generation

Abstract: The application of superconductors in the field windings of large steam-turbine generators appears to offer a number of significant economic and operational advantages. The principal advantage offered by such machines appears to be a potentially large reduction in size, weight, and cost for a given power rating. In addition, superconducting alternators also appear to have a number of unique and potentially advantageous operational characteristics, most of which are a consequence of the relatively low per-unit synchronous reactance that is characteristic of these machines. This paper reviews the reasons for the low synchronous reactance attributable to the use of superconducting field winding, and compares the expected performance characteristics of a superconducting alternator in the 1000 MVA range with those of a conventional power system generator of comparable rating. Among the specific topics discussed are performance with regard to dynamic stability, transient stability, voltage regulation, and excitation control. The principal operational advantages of a superconducting alternator appear to be 1) the absence of a dynamic stability limit within its MVA capability, 2) significantly greater transient stability when operating at leading power factors, 3) superior voltage regulation, and 4) no degradation of dynamic stability due to automatic voltage regulator action. Consequently, superconducting alternators appear to be ideally matched to modern power system applications that require operation of generators at leading power factors.

Wide dynamic current range switching regulator

Abstract: A switching regulator is adaptable for connection to a DC power source to serve as a power supply. A self-oscillating switching regulator has an output voltage feedback circuit connected thereto which interrupts the self-oscillating circuit when the output voltage rises above a prescribed level. The current that flows through a power switch of the regulator is sensed and when it gets beyond a predetermined amount, a Schmidt trigger circuit is turned off. The Schmidt trigger circuit then turns off the power switch, permitting the inductor in the switching regulator circuit to supply current to an output filter capacitor. When the voltage across the capacitor builds up to a prescribed level, the feedback circuit detects the level and deactivates the Schmidt trigger which turns off the power switch.

Overload protection circuit for voltage regulator

Abstract: When the load current of a voltage regulator rises above a safe value for sustained operation, a limiting circuit is activated to prevent further rise. At the same time, a capacitor in a timing circuit is being charged so that if the overload condition continues beyond a predetermined amount, the capacitor voltage will trigger a latching circuit to shut off the regulator. The regulator is reset by merely turning off the supply long enough to allow the capacitor to discharge.

Conversion system with overcurrent protection and start-up circuitry

Abstract: Circuitry for providing high voltage DC power from commercially available 60 hertz AC utility power. The incoming 60 hertz AC voltage is rectified to a DC voltage. This DC voltage is then converted to a high frequency AC voltage by means of a sine wave inverter. This high frequency sine wave voltage is then converted to a different voltage and rectified by a voltage doubler. The inversion and rectification are under the control of logic circuitry which includes means for sensing line faults to provide circuit protection.

Wide input range switching voltage regulator

Abstract: A switching transistor connects an input terminal at which a wide range of voltage levels may be impressed with an output terminal at which a relatively constant voltage is desired. A charge storage circuit whose discharge frequency is controlled in accordance with the output voltage and discharges a further charge storage circuit operating in accordance with the input voltage level. The further charge storage circuit controls the ON-OFF state of the switching means. Switching transistor turn off transient energy is inductively coupled to the output terminal.

Electric power system supervisory control system comprising A/D converters at various points of the power system

Abstract: A supervisory control system for an electric power system comprises a synchronized encoder for producing digital signals from voltage and/or current data detected by at least one of a number of detecting devices for such data coupled to the power system at various points. Inherently stationary data detected by similar detecting devices are converted into digital signals by asynchronous encoders. Responsive to such digital signals, data processing means produces address signals representative of the addresses of the detecting devices and processes the digital signals in compliance with programs for various supervisory control and with reference to the address signals to produce control signals, which are sent to circuit breakers, voltage regulators, and the like to protect the power system against troubles.