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Showing papers on "Precision rectifier published in 1976"


Patent
15 Mar 1976
TL;DR: In this paper, a position indicator is disclosed which includes the combination of a linear voltage differential transformer (LVDT) and accuracy assurance circuitry, which permits the disclosed indicator to operate substantially independent of fluctuations in input voltage or frequency.
Abstract: A position indicator is disclosed which includes the combination of a linear voltage differential transformer (LVDT) and accuracy assurance circuitry. The LVDT includes a movable core connected to a mechanism whose position is to be indicated. The accuracy assurance circuitry permits the disclosed indicator to operate substantially independent of fluctuations in input voltage or frequency. This substantial independence is achieved in the following manner. First, the voltage across the LVDT is rectified by a first precision rectifier. Simultaneously, the LVDT tap voltage is rectified by a second precision rectifier. Each precision rectifier output is filtered and then applied to an analog divider which "cancels out" the effects of input voltage or frequency fluctuation. The divider output is an analog signal which is a true ratio of tap voltage to voltage across the LVDT. This true ratio signal accurately represents the position of the mechanism connected to the movable core.

36 citations


Patent
28 Jan 1976
TL;DR: In this paper, a three-phase rectifier circuit is connected to provide a d-c output voltage as a function of the 3-phase energy passed to the rectifier, which is reduced in amplitude over a voltage divider circuit and passed through an optically-coupled detector circuit.
Abstract: A three-phase rectifier circuit is connected to provide a d-c output voltage as a function of the three-phase energy passed to the rectifier circuit. This energy is reduced in amplitude over a voltage divider circuit and passed through an optically-coupled detector circuit to provide a control signal indicating the presence of energy on all phase conductors of the supply line. If a fuse blows in one line, or if the power on that line is interrupted for any reason, the ripple content of the rectified voltage increases. This is sensed by a detector circuit to energize an alarm and/or interrupt the main power bus to the load.

24 citations


Patent
Donald E. Griffey1
14 Apr 1976
TL;DR: In this article, a television receiver protection system providing X-ray protection to the viewer responds to rectified horizontal flyback pulses supplied to the gate electrode of a silicon controlled rectifier through a zener diode.
Abstract: A television receiver protection system providing X-ray protection to the viewer responds to rectified horizontal flyback pulses supplied to the gate electrode of a silicon controlled rectifier through a zener diode to trigger the silicon controlled rectifier into conduction when the high voltage level from the flyback transformer of the receiver becomes abnormally high. The silicon controlled rectifier is connected across the power supply for the horizontal oscillator, so that the horizontal oscillator is rendered inoperative when the silicon controlled rectifier becomes conductive.

19 citations


Patent
19 Apr 1976
TL;DR: In this paper, an improved switching circuit with overload protection for transforming a source of direct current power into a pulsating voltage of constant frequency and variable pulse duration adapted to be connected through a load to a first controllable rectifier of the switching circuit which in turn is connected through current sensing resistor to a common circuit ground.
Abstract: There is disclosed an improved switching circuit with overload protection for transforming a source of direct current power into a pulsating voltage of constant frequency and variable pulse duration adapted to be connected through a load to a first controllable rectifier of the switching circuit which in turn is connected through a current sensing resistor to a common circuit ground. The gate electrode of the first controllable rectifier is connected to a source of constant frequency pulses of variable duration. The secondary winding of a current transformer is connected from the common circuit ground in series with a diode, the cathode of which is connected to the anode of a second controllable rectifier, the cathode of the second controllable rectifier being connected to the common circuit ground. The gate of the second controllable rectifier is coupled to a source of pulses which are the exact complement to the pulses applied to the gate of the first controllable rectifier. The primary of the transformer is connected from the common circuit ground in series with a charging capacitor, which in turn is connected to the anode of the first controllable rectifier. The anodes of the first and second controllable rectifiers are connected through a "turn-off" capacitor. A first comparator amplifier has an input connected to the junction of the current sensing resistor and the first controllable rectifier and an output connected through an integrating circuit to a second comparator amplifier, the output of which is connected to a power contactor for applying and removing power to the switching circuit.

17 citations


Patent
Moltgen G1
11 Mar 1976
TL;DR: In this paper, an apparatus for compensating for the reactive power in a three-phase network is described, consisting of an uncontrolled rectifier, an intermediate DC link connected to the rectifier and a self-commutating inverter.
Abstract: An apparatus for compensating for the reactive power in a three-phase network. The apparatus includes an uncontrolled rectifier, an intermediate DC link connected to the rectifier, and a self-commutating inverter connected to the DC link and controlled so as to have a pulse-width modulated output.

16 citations


Patent
08 Dec 1976
TL;DR: In this paper, a heart/lung function measuring apparatus comprises a source for permitting a constant slight current of a high frequency wave of predetermined frequency to flow through a to-be-measured portion of a living body, a voltage detection section detecting a voltage loop based on the impedance of the living body area, a sample-hold circuit for sampling a predetermined level of an output signal of the voltage detector and holding the sampled value, a peak detector for generating a detector output according to a peak voltage of the output of the detection section, a pulse generator for generating the pulse signal
Abstract: A heart/lung function measuring apparatus comprises a source for permitting a constant slight current of a high frequency wave of predetermined frequency to flow through a to-be-measured portion of a living body, a voltage detection section detecting a voltage loop based on the impedance of the living body area, a sample-hold circuit for sampling a predetermined level of an output signal of the voltage detection section and holding the sampled value, a peak detector for generating a detector output according to a peak voltage of the output of the detection section, a pulse generator for generating a pulse signal which is applied as a trigger signal to the sample-hold circuit according to the output of the peak detector, and a subtractor for obtaining a difference output between the output of the voltage detection section and the output of the sample-hold circuit.

15 citations


Patent
12 Oct 1976
TL;DR: In this article, the collector and emitter electrodes of a control transistor are connected between the gate and cathode electrodes of the rectifier to prevent the semiconductor controlled rectifier from conducting surge currents.
Abstract: A surge current protection circuit includes an input terminal supplied with a rectified alternating voltage, an output terminal to be connected to a load, and a semiconductor controlled rectifier having its anode and cathode electrodes connected in series between the input and output terminals. The collector and emitter electrodes of a control transistor are connected between the gate and cathode electrodes of the rectifier. The base-emitter voltage is supplied with any sharp transients, and the transistor becomes conductive before the rectifier if the transients are sharp enough and of high enough amplitude. Conduction of the transistor prevents the semiconductor controlled rectifier from conducting surge currents and protects circuits connected in series with the rectifier.

14 citations


Patent
25 Nov 1976
TL;DR: In this paper, the fault-current circuit, for protective circuit-breakers, derives an auxiliary voltage from the mains supply via a rectifier, and two rectifying paths are provided for each line.
Abstract: The fault-current circuit, for protective circuit-breakers, derives an auxiliary voltage from the mains supply via a rectifier. Two rectifying paths are provided for each line. Four or more rectifying paths (G) belonging to two or more lines form a bridge circuit. The auxiliary voltage (Uh) is obtained from one of the bridges diagonals. A capacitor may also be connected across this diagonal. Linear or non-linear resistors are connected before the rectifiers. These resistors may be integrated with the rectifiers.

13 citations


Patent
08 Jan 1976
TL;DR: In this article, a DC motor with a series field winding and with a semi-conductor rectifier arrangement in parallel with the field winding was used for variable shunting of a field winding.
Abstract: Drive equipment supplied with direct current, which includes a DC motor with a series field winding and with a semi-conductor rectifier arrangement in parallel with the field winding and working in pulse operation for variable shunting of the field winding. The controllable semi-conductor rectifier has a reactor connected in series with it. A load object is connected in parallel to the semi-conductor rectifier. The load object may be an accumulator battery series-connected with a second semi-conductor rectifier which blocks the battery voltage.

12 citations


Patent
Joe E. Marriott1
26 Mar 1976
TL;DR: In this paper, an improved feedback/compensation scheme for a precision active rectifier circuit improves the slew rate and loop gain during diode switching and thereby reduces fractional scale linearity problems.
Abstract: An improved feedback/compensation scheme for a precision active rectifier circuit improves the slew rate and loop gain during diode switching and thereby reduces fractional scale linearity problems.

7 citations


Patent
03 Apr 1976
TL;DR: In this paper, a rectifier has a transformer with an externally controlled invertor on its primary side, and a self-controlled rectifier and inverter on its secondary side, commutating through its dc side.
Abstract: The rectifier has a transformer (3) with an externally controlled invertor (1) on its primary side, and a self-controlled rectifier and inverter (2) on its secondary side, commutating through its dc side. A smoothing capacitor is on its dc side. Higher frequency of the leading secondary voltage (U F2) at the transformer (3) is adjusted by control of diodes of the self-controlled rectifier and invertor (2). The latter controls the input side invertor (1). The low frequency is passed through an auxiliary transformer in parallel with the hf side and is applied across a diagonal of an uncontrolled four element rectifier. The output from the outer diagonal is fed out in parallel with the hf invertor output.

Patent
07 Sep 1976
TL;DR: In this article, a plurality of transistors are connected between the at least one rectifier and a general purpose integrated circuit with a threshold value, each of which is controlled in its on/off operation by the d.c. signal from the rectifier in order to control the output potential of the integrated circuit.
Abstract: An a.c. input signal is supplied to at least one input terminal to which at least one rectifier is connected for converting the a.c. input signal to a d.c. signal corresponding thereto. A plurality of transistors are connected between the at least one rectifier and a general purpose integrated circuit with a threshold value. Each of plural transistors is controlled in its on/off operation by the d.c. signal from the rectifier in order to control the output potential of the integrated circuit. A plurality of indicators are connected between a d.c. power source and outputs of the integrated circuit to be discretely and sequentially energized to indicate a peak level of the a.c. input signal.

Patent
04 Aug 1976
TL;DR: In this article, a voltage controller is operated by pulse width modulation and a current limiter is provided, where a current transformer (W) has its primary winding (I) connected in series with the capacitor (K1) and a diode (D2) and with a capacitor(K2) connected to the secondary winding (II) in parallel with a load resistor (B).
Abstract: A voltage controller is operated by pulse width modulation and a current limiter is provided. A current transformer (W) has its primary winding (I) connected in series with the capacitor (K1) and a diode (D2) and with a capacitor (K2) is connected to the secondary winding (II) in parallel with a load resistor (B). It generates a DC voltage proportional to the output current (IA). The diode (D2) and transformer secondary winding (II) are so arranged that only capacitor (K1) discharge current is evaluated, with the diode (D2) and capacitor (K2) operating as a peak detector.

Patent
13 May 1976
TL;DR: An assembly of components for monitoring an electrical circuit, and which truly indicates whether the circuit is working; the assembly including a voltage transformer in series with a minimum resistance load, a secondary winding of the transformer communicating with a full wave bridge rectifier connected through a gate, cathode, silicon controlled rectifier and silicon rectifier diode to a pilot lamp.
Abstract: An assembly of components for monitoring an electrical circuit, and which truly indicates whether the circuit is working; the assembly including a voltage transformer in series with a minimum resistance load, a secondary winding of the transformer communicating with a full wave bridge rectifier connected through a gate, cathode, silicon controlled rectifier and silicon rectifier diode to a pilot lamp.

Patent
02 Sep 1976
TL;DR: In this article, a diode in parallel with a resistor is connected in circuit with the secondary winding of a re-actor to limit the magnitude of the reverse recovery current in the re-sistor.
Abstract: OF THE DISCLOSURE A circuit for controlling the reverse recovery current in a controlled rectifier. The primary winding of a satur-able reactor is connected in series with the controlled rectifier. A diode in parallel with a resistor is connected in circuit with the secondary winding of the saturable re-actor. The diode is poled to provide a low impedance in the reactor secondary when current flows through the primary winding and through the forward direction of the controlled rectifier flowing through the primary winding of the re-actor causes current in the secondary winding to flow in the reverse direction of the diode. The value of the re-sistor as reflected into the saturable reactor primary circuit limits the magnitude of the reverse recovery current.

Patent
Carlo Infante1
15 Oct 1976
TL;DR: In this paper, the current in the deflection coil of a video display system is converted into a DC voltage and applied to a peak detector, where the peak values of the DC voltages as stored by the peak detector are amplified and then compared with a reference voltage at the input of a comparator amplifier.
Abstract: The current in the deflection coil of a video display system is converted into a DC voltage and applied to a peak detector. Peak values of the DC voltages as stored by the peak detector are amplified and then compared with a reference voltage at the input of a comparator amplifier. The comparator amplifier provides an output as a base drive to a regulating transistor that has an emitter-collector junction in series with the deflection coil and an unregulated source of DC power.

Patent
23 Sep 1976
TL;DR: In this article, a demagnetising circuit for magnetic flux lines, using a demagnetic coil supplied from an ac source and coupled to the magnetic flux line, is described, where the demagnetic coils are connected on the ac side of a full wave rectifier and a dropper impedance is provided in the ac and the dc sides of the rectifier.
Abstract: A demagnetising circuit for magnetic flux lines, using a demagnetising coil supplied from an ac source and coupled to the magnetic flux line. The demagnetising coil (1) is connected on the ac side of a full wave rectifier (4). There is a capacitor (5) between the dc terminals of the full wave rectividr, and a dropper impedance (2) is provided in the ac and the dc sides of the rectifier. The full wave rectifier can be a Graetz rectifier, a Dellon cascade rectifier, or a controlled semi-conductor bridge rectifier. The dropper impedance on the ac side of the bridge rectifier can be an ohmic resistance (13) and a capacitor (12) or an inductance, or a combination of any of these elements.

Patent
29 Mar 1976
TL;DR: In this paper, a receiver has a first input circuit and a first amplifier connected to a first rectifier circuit and has a second input circuit, and a second amplifier is connected to the second rectifier.
Abstract: A receiver has a first input circuit and a first amplifier connected to a first rectifier circuit and has a second input circuit and a second amplifier connected to a second rectifier circuit. The first and second rectifier circuits produce first and second direct current signals, and the first and second rectifier circuits are connected to a meter drive circuit which produces a direct current signal in response to the first or second direct current signal so that the direct current signal from the meter drive circuit actuates a meter to indicate the input level of either the first input circuit or second input circuit.

Patent
12 Apr 1976
TL;DR: In this paper, a plurality of rectification circuits, each including a diode and a filter capacitor, are located at different positions along the line to detect the amplitude of a RF signal propagating along a transmission line.
Abstract: A circuit for detecting the amplitude of a RF signal propagating along a transmission line. A plurality of rectification circuits, each including a diode and a filter capacitor, are located at different positions along the line. The signal electrodes of the capacitors are connected together to thereby non-additively combine the signals seen at each rectifier. The spacing between the rectifier circuits is carefully selected and will vary with the number of rectifier circuits used. If two rectifiers are employed, the distance therebetween may conveniently be equal to an odd multiple of one-quarter of the wavelength of the driving signal. For this spacing, the combined signal will never fall below the amplitude of the signal produced when the transmission line is terminated with a perfectly matched load. Additionally, the output of the detector will be generally responsive to VSWR. Other RF level detectors having greater numbers of rectifier circuits are also described. In one embodiment, the detector output is directed to the gain control input of an RF amplifier to provide feedback stabilization thereof. Because the voltage level is sensed on the transmission line, high VSWR will cause a high rectifier output, thus automatically reducing drive to the power amplifier.

Patent
17 Dec 1976
TL;DR: The gamma correction circuit for a television film scanner has the same number of controllable gamma circuits as there are colour signals as discussed by the authors, and each gamma circuit is controlled by the output from an average value detector that determines the average of the input signal.
Abstract: The gamma correction circuit, for a television film scanner, has the same number of controllable gamma circuits as there are colour signals. Each signal is fed to an amplifier whose gain is controlled by a peak detector, and each gamma circuit is controlled by the output from an average-value detector that determines the average of the input signal. The film is pre-scanned by a photoelectric device included in the correction circuitry to allow coarse adjustment for each film frame before the actual gamma correction takes place. The outputs of the average-value detectors are also coupled to the photoelectric device.

Patent
16 Jun 1976
TL;DR: In this article, the welding arrangement is connected to a current source connected via a welding current to an electrode and to the workpiece or a counter electrode, also connected to an ignition circuit.
Abstract: The welding arrangement is connected to a current source connected via a welding current to an electrode and to the workpiece or a counter electrode. The current source is also connected to an ignition circuit. A rectifier is incorporated in the welding current circuit on in the ignition current circuit, to block the welding energy. If the current source is a D.C. source, a diode is used as rectifier. If the current source is A.C., two controllable rectifiers preferably thyristors are used. The current source is provided with controls to adjust current and/or voltage.

Patent
12 Aug 1976
TL;DR: In this paper, a direct voltage converter for transferring charge between batteries of different terminal voltages has a static inverter coupled via a transformer to a rectifier, which is so poled that it supplies current to one battery when the transformer (12) magnetic field collapses.
Abstract: The direct voltage converter for transferring charge between batteries of different terminal voltages has a static inverter coupled via a transformer to a rectifier. The static inverter consists of four semi-conductor controlled rectifiers (23-26) connected to form a bridge with a capacitor (28) in one diagonal. The rectifier is so poled that it supplies current to one battery when the transformer (12) magnetic field collapses. The controlled rectifiers are controlled from a variable frequency oscillator (31), which is itself controlled (40) in conjunction with the rectifier output voltage. The advantage of this converter arrangement lies in its giving maximum reliability and optimum energy transfer.

Patent
29 Jan 1976
TL;DR: In this paper, the automatic peak colour control consists of an adjustable reference source, a chrominance signal amplifier, a voltage shift circuit, a detector, a peak detector and a comparator.
Abstract: Colour television receiver with a circuit for maintaining a substantially constant peak signal level in spite of variations in the ratio between the colour synchronisation signal and the chrominance signal. It consists of a luminance channel, a supply, a high voltage source for synchronisation and deflection and a chrominance signal amplification stage which feeds into a chrominance demodulator. The automatic peak colour control consists of an adjustable reference source, a chrominance signal amplifier, a voltage shift circuit, a detector, a peak detector and a comparator. The detector and the voltage shift network are connected to the peak detector via a buffer amplifier.

Patent
23 Dec 1976
TL;DR: In this article, the harmonics of the control variable at the rectifier output are represented in the form of a corresponding voltage by measuring the total voltage at the Rectifier output.
Abstract: Harmonics of the control variable at the rectifier output are at first represented in the form of a corresponding voltage by measuring the total voltage at the rectifier output. Difference between this voltage and control voltage at the rectifier input is produced by a subtractor circuit. The control voltage corresponds to the fundamental of the rectifier output voltage, so that the difference voltage corresponds to the harmonics in the output voltage. A computer circuit, which simulates the relation between voltage and current, separates the harmonics in the rectifier output current, and this current is subtracted from the total current by a further subtractor circuit, so that the resultant current is nearly completely free from harmonics.

Patent
19 Nov 1976
TL;DR: In this article, a single phase network has a transformer (T) on the main's side and has the pulse current rectifier (PSR) connected with a phase following rectifier on the secondary side.
Abstract: Torque and speed of the asynchronous rectifier machines are controlled, and the machines are supplied from the mains through a rectifier unit consisting of a pulse current rectifier and phase sequence rectifier with impressed intermediate circuit current. Input voltage (Uc) of the pulse current rectifier can be controlled within a freely selectable sinusoidal tolerance band using a filter (Li, C) on the main side. The single phase network has a transformer (T) on the main's side and has the pulse current rectifier (PSR) connected with a phase following rectifier (PFSR) on the secondary side. A number of measured value converters (MUuO) are connected to tappings at various stages in the circuit.

Patent
22 Jul 1976
TL;DR: In this paper, the input chopper is controlled by a rectangular signal and the rectifier circuit is regulated by a control signal, where the keying ration of the signal is smaller than that of the control signal.
Abstract: The input chopper is controlled by a rectangular signal and the rectifier circuit is regulated by a control signal. The keying ration of the signal is smaller than that of the control signal which is used to regulate the input chopper and it blocks the rectifier when the switching peaks appear at the amplifier output, as in 2355580. A multivibrator with a trapezoidal output voltage controls the rectifier (3)to the multivibrator which converts the trapezoidal voltage into a rectangular voltage whic is used for the input chopper control.

Journal ArticleDOI
01 Dec 1976