Showing papers on "Buck–boost converter published in 1981"
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22 Oct 1981TL;DR: A buck boost type noninverting transformerless switching regulator utilizes two synchronized switches operating at either the same or different duty cycles to independently control energy storage and energy delivery from a two terminal inductor element to the output load as mentioned in this paper.
Abstract: A buck boost type noninverting transformerless switching regulator utilizes two synchronized switches operating at either the same or different duty cycles to independently control energy storage and energy delivery from a two terminal inductor element to the output load. A wide range of output voltage is available and is continuously regulated.
82 citations
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18 Dec 1981
TL;DR: In this article, a power converter which supplies AC or positive or negative DC output voltage with AC or negative output voltage while isolating the output voltage from the input power source is described.
Abstract: A power converter which supplies AC or positive or negative DC output voltage with positive or negative current while isolating the output voltage from the input power source This converter includes a pulse width modulator converts power amplitude signals to pulses of proportionate width A power driver circuit applies these pulses to a sychronous demodulator and low pass filter via a pulse transformer A low output impedance is presented to all output disturbances such that the converter can source or sink current in true four quadrant operation, including the passing of power from output to input when a load voltage exceeds the intended supply voltage
71 citations
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31 Aug 1981TL;DR: In this article, a DC/DC converter operates at peak efficiency in either of two output current level states in response to the power demands of an associated electronic device, thereby reducing wasted current to a minimum.
Abstract: A DC/DC converter operates at peak efficiency in either of two output current level states in response to the power demands of an associated electronic device, thereby reducing wasted current to a minimum. The converter is designed to operate from a one-cell battery, and is particularly suited to an integrated circuit implementation.
52 citations
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11 Dec 1981TL;DR: In this article, the maximum current supplied from a battery to the converter's transformer is determined solely by the battery recovery voltage, circuit resistances, the transformer turns ratio and semiconductor junction voltages.
Abstract: A DC to DC flyback converter for charging a capacitor in which the maximum current supplied from a battery to the converter's transformer is determined solely by the battery recovery voltage, circuit resistances, the transformer turns ratio and semiconductor junction voltages.
45 citations
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TL;DR: In this paper, an offset-free switched-capacitor gain stage is described, which combines the gain stage with a binary weighted capacitor array, and a D/A converter is obtained.
42 citations
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12 Feb 1981TL;DR: In this article, a free-running blocking oscillator-type converter for producing a controlled output signal is described, where a primary winding of a transformer, a switching transistor, and a resistor are connected in series with one another between first and second input terminals of the converter.
Abstract: A free-running blocking oscillator-type converter for producing a controlled output signal. The converter is provided with a primary winding of a transformer, a switching transistor, and a resistor which are connected in series with one another between first and second input terminals of the converter. The transformer is further provided with a feedback winding which is coupled to the base terminal of the switching transistor. In some embodiments, optoelectronic coupling devices are used in a sensor arrangement for providing a control signal responsive to variations in the magnitude of the output signal of the converter. In other embodiments, such variations in the output signal of the converter are sensed by a transformer winding. Circuitry is disclosed for applying the sensor control signal selectably to the base and emitter terminals of the switching transistor.
33 citations
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19 Aug 1981TL;DR: In this paper, an analog-to-digital converter is used to control a predetermined timed discharge from a selected one of the series of capacitors, which can be used in a video system as an adaptive contrast enhancement mechanism.
Abstract: An improvement in an analog-to-digital converter wherein a series string of capacitors is utilized to generate reference voltages for the comparators of the converter. The digitized output of the converter is then used to control a predetermined timed discharge from a selected one of the series string of capacitors. The converter, as described, may be used in a video system as an adaptive contrast enhancement mechanism.
23 citations
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01 Jun 1981TL;DR: In this article, the generalized approach to the instability in boost and buck-boost converters is described, and the maximum regulation range for the load resistance is discussed, and a generalized approach is proposed to deal with the problem.
Abstract: In boost and buck-boost converters, an unstable phenomenon occurs and the output voltage oscillates when the feedback gain is high and the load becomes heavy. On the other hand, even when the feedback gain is relatively low, another instability arises under some conditions of load resistance, and then the dc output voltage jumps down to an extremely low level. This paper describes the generalized approach to the instability in boost and buck-boost converters, and discusses the maximum regulation range for the load resistance.
20 citations
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01 Jan 1981TL;DR: In this article, the facility of an augmented Lagrangian (ALAG) multiplier based nonlinear programming technique is demonstrated for minimum weight design optimizations of boost and buck-boost power converters.
Abstract: The facility of an Augmented Lagrangian (ALAG) multiplier based nonlinear programming technique is demonstrated for minimum- weight design optimizations of boost and buck-boost power converters. Certain important features of ALAG are presented in the framework of a comprehensive design example for buck-boost power converter design optimization. The study provides refreshing design insight of power converters and presents such information as weight and loss profiles of various semiconductor components and magnetics as a function of the switching frequency.
19 citations
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09 Oct 1981TL;DR: In this paper, a two-stage analog-to-digital converter with a successive-approximation register was proposed, where the first stage is a resistor-string d-toa converter controlled by a successive approximation register, functioning in a first phase of the conversion operation to determine a set of higher order bits of the digital output signal.
Abstract: A two-stage analog-to-digital converter wherein the first stage is a resistor-string d-to-a converter controlled by a successive-approximation register, functioning in a first phase of the conversion operation to determine a set of higher order bits of the digital output signal The second stage is a dual-slope integrating-type a-to-d converter functioning in a second phase of the conversion operation to determine the remaining lower-order bits of the digital output signal The dual-slope converter receives a reference signal derived from two adjacent junction points of the first-stage resistor-string d-to-a converter corresponding to the higher order bits determined in the first phase of operation, thereby to assure high resolution performance
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13 Feb 1981TL;DR: In this paper, an integrated circuit comprising a plurality of adjustable voltage-current converters, of which one converter is employed as a reference converter, is included in a control loop.
Abstract: An integrated circuit comprising a plurality of adjustable voltage-current converters, of which one converter is employed as a reference converter. The reference converter is included in a control loop. To the input of the reference converter an input voltage is applied in that a first current is passed through a reference resistor connected to said input. A second current, which is in a fixed ratio to said first current, is compared with the output current of the reference converter and this reference converter is then biassed so that its output current corresponds to said second current. In this way the transconductance of the reference converter is determined by the reference resistor and the ratio of the first and the second current, so that this transconductance is highly independent of process, temperature and supply-voltage variations. The other converters are biassed by signals derived from the bias signals for the reference converter and thus have corresponding transconductances.
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25 Mar 1981
TL;DR: The digital-to-analog converter comprises an R-2R ladder network with bit controlled current steering switches connecting the legs of the ladder network to first and second current buses as discussed by the authors.
Abstract: The digital-to-analog converter comprises an R-2R ladder network with bit controlled current steering switches connecting the legs of the ladder network to first and second current buses. First and second current-to-voltage converters are connected to the current buses respectively, the second current-to-voltage converter being connected through a switch to the input of the first current-to-voltage converter. A uni-polar/bi-polar control signal renders the switch conductive or non-conductive in accordance with the data format desired. The digital-to-analog converter is also utilized in a successive approximation analog-to-digital converter.
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09 Jan 1981TL;DR: In this paper, a method for reducing main feedback from a line-commutated direct converter (I, II) when connected to a three-phase mains supply (R, S, T) by modulating a controllable reactive power compensator (5, 6, 7) is presented.
Abstract: 1. A method for reducing main feedback from a line-commutated direct converter (I, II) when connected to a three-phase mains supply (R, S, T), by modulating a controllable reactive power compensator (5, 6, 7) connected to the three-phase mains, characterised in that the theoretical value (i*B ) for the control (8) of the reactive current to be supplied by the reactive power compensator is formed independently of the actual value of the reactive current, from the product ( iA . cos psi = iq1 ) of the amount of the direct converter output current (iA ) and a predetermined function (cos psi) of the direct converter control angle (psi) derived from the control voltage (UST ) of the direct converter (I, II) or from the direct converter output voltage (Ua ) (Figure 1).
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23 Dec 1981TL;DR: In this article, an AC motor drive including a source side converter and a load side converter coupled together by means of a DC link circuit where the current in the DC-link circuit is controlled by either the source-side converter or load-side-converter depending upon which converter is capable of control.
Abstract: A control system for an AC motor drive including a source side converter and a load side converter coupled together by means of a DC link circuit wherein the current in the DC link circuit is controlled by either the source side converter or load side converter depending upon which converter is capable of control. This is achieved by crosstieing a signal from the normal regulating path in the source side converter control to the alternate regulating path in the load side converter control. This signal is chosen to be indicative of the source side converter controller being unable to control current, and may be derived from current error. This signal operates to alter the firing angle of the load side thyristor bridge to regulate the DC link current in the event the source side converter is unable to maintain the required current regulation.
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08 Jan 1981
TL;DR: In this article, an auxiliary winding (6) is provided in the converter transformer of a high-voltage DC transmission system for controlling the line-commutated valves of a converter, which is connected to the network via a converter transformer.
Abstract: In the case of a device for producing the correct-phase image of the high AC voltage (U1) of a network for controlling the line-commutated valves of a converter, which is connected to the network via a converter transformer (1, 2, 3, 4), in a high-voltage DC transmission system, an auxiliary winding (6) is provided in the converter transformer.
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27 Feb 1981TL;DR: In this article, a choke is introduced in a common emitter circuit of switching transistors in a push-pull saturation converter, and a constriction may be provided in a center leg of a transformer core of a switching transformer within the converter.
Abstract: To increase the efficiency of a push-pull saturation converter, a choke is introduced in a common emitter circuit of switching transistors in the converter. In addition, a constriction may be provided in a center leg of a transformer core of a switching transformer within the converter. To further improve efficiency, an RC acceleration element may be provided in a base circuit for the switching transistors.
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03 Sep 1981
TL;DR: In this article, a beat phenomenon detector was proposed to prevent the mutual interference of frequencies between the input and the output of an AC generator when a variable speed drive source and a load is connected through a stationary converter, thereby correcting a frequency command.
Abstract: PURPOSE:To prevent the mutual interference of frequencies between the input and the output by providing a beat phenomenon detector when an AC generator is driven by a variable speed drive source and a load is connected through a stationary converter, thereby correcting a frequency command. CONSTITUTION:An AC generator 1 is driven by an engine or the like, and electric power is supplied through a stationary converter 2 which has a power reactor 3 and a power inverter 6 to a load 7. At this time, a beat phenomenon detector 10 is provided at the output side of the converter 2, a frequency command to a frequency converter 9 is corrected by the output, thereby slightly displacing the frequency command. Accordingly, frequency difference can be always produced between the input and the output of the converter 2, thereby reducing the size of the system without increasing the reactor 4 and the condenser 5 in the converter 2 and preventing the beat phenomenon which occurs when the frequencies of the input and output approach to each other.
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19 May 1981TL;DR: In this paper, a dc-to-dc converter of resonant type regulated by PWM means is presented, which consists of two stages, the first stage is the boost converter with a switch of MOS FET, the change of the output voltage is regulated by this switch.
Abstract: A dc-to-dc converter of resonant type regulated by PWM means is presented. The converter consists of two stages. The first stage is the boost converter with a switch of MOS FET. The change of the output voltage is regulated by this switch. The second stage is the self-oscillating inverter with rectified output. In the dc side of the output rectifier, a parallel capacitor is connected. A resonant condition is satisfied between the capacitor and the leakage inductance of the inverter transformer. The resonant frequency is almost the same as that of the oscillating frequency. With the resonance phenomena, the switching loss of the transistor is decreased. A good regulation is obtained by the feedback from the output to the boost converter.
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TL;DR: A new pulse delay circuit for converter control that can be used for many converter configurations employing line and forced commutations is described.
Abstract: A new pulse delay circuit for converter control is described. The circuit is versatile in the sense that- it can be used for many converter configurations employing line and forced commutations.
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24 Sep 1981
TL;DR: In this paper, a converter for converting an a.c. voltage (SP) into a direct current (i 3 ) is described, which is used for regulating the amplitude of the oscillation signal of an oscillator.
Abstract: A converter (300) for converting an a.c. voltage (SP) into a direct current (i 3 ), characterized in that it comprises a first elementary converter (21) which, in response to the a.c. voltage (SP), provides a pulsed direct current (i 1 ), the mean value (i 1 ) of which is a steeply rising function of the amplitude A of the a.c. voltage (SP), and a second elementary converter (22) which, in response to the current i 1 provides a current i 3 , the value of which is a steeply falling function of i 1 . Used for regulating the amplitude of the oscillation signal of an oscillator.
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27 Jan 1981
TL;DR: In this article, an AC-AC converter device comprising a converter circuit capable of producing an instantaneously varying output voltage, and a coupled reactor commutating inverter circuit cascade-connected thereto, was presented.
Abstract: The present invention is an AC--AC converter device comprising a converter circuit capable of producing an instantaneously varying output voltage, and a coupled reactor commutating inverter circuit cascade-connected thereto, the inverter circuit having a plurality of thyristors which are rendered conductive in a predetermined sequence, in which the output voltage of the converter circuit is rendered positive, negative or zero as necessary to effect commutation and current control in the inverter circuit.
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TL;DR: In this paper, a new converter scheme suitable for the high power single-phase converter to overcome the above problems is presented, and the basic configuration and principle of operation, theoretical characteristics and design indexes, and drive system and characteristics of a dc series motor by this scheme are described.
Abstract: Power-factor improvement and harmonic reduction in ac line current, as well as stable and reliable operation, are very significant areas in the high-power ac-dc converter. The improvements of these characteristics of the single-phase converter may be generally difficult compared with the polyphase type. A new converter scheme suitable for the high power single-phase converter to overcome the above problems is presented. The basic configuration and principle of operation of the new converter scheme, theoretical characteristics and design indexes, and the drive system and characteristics of a dc series motor by this scheme are described. The basic principle of operation is verified and the feasibility of this converter system is demonstrated by experiments.
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29 Jan 1981
TL;DR: In this paper, a power supply unit for electrical equipment, primarily agricultural electric fences, using solar cells, dc/dc converter and storage batteries is described, where the output from the solar cells is controlled by an output switching transistor associated with the output diode.
Abstract: Power supply unit for electrical equipment, primarily agricultural electric fences, using solar cells, dc/dc converter and storage batteries. The dc/dc converter circuit also regulates the output from the solar cells for optimum performance, i.e. supply to equipment and charging batteries under sunny and cloudy conditions but allowing discharge to power the equipment at night and during rainy weather. The dc/dc converter (11) raises the lower voltage output (U1) from the solar cells (4), under adverse light conditions, to the value required (U2) for charging the storage accumulators (5). The converter also charges the accumulators directly via the primary (1) of the converter transformer and a diode (8) when the solar cell (4) output exceeds the accumulator (5) potential under favourable conditions. Operation is controlled by an output switching transistor (2) associated with the output diode (8) and by the converter internal circuitry (13).
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14 May 1981
TL;DR: In this article, a three phase converter with a return section for each phase, for operating a machine at high loads and low speeds, with their output sides star connected, reduces the blind loading.
Abstract: The three phase converter with a return section for each phase, for operating a machine at high loads and low speeds, with their output sides star connected, reduces the blind loading. Within the control region, each section is fully controlled by a variable additional voltage. The resulting combined output voltage is sinusoidal. Each section is cyclically reversed at the output frequency of the direct converter. The frequency of the additional control voltage corresponds to the output frequency multiplied by the number of phases. The control voltage is obtained from the differences of maximum and minimum sinusoidal values.
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04 Dec 1981
TL;DR: In this article, the authors proposed a method to prevent breakage of self arc-distinction type semiconductor element caused by application of OFF control signal, by a method wherein when current of the self arc distinction type semiconduct element becomes over a prescribed value both ON and OFF control signals to be applied thereto are interrupted.
Abstract: PURPOSE:To prevent breakage of self arc-distinction type semiconductor element caused by application of OFF control signal, by a method wherein when current of the self arc-distinction type semiconductor element becomes over a prescribed value both ON and OFF control signals to be applied thereto are interrupted. CONSTITUTION:Pulse width modulation PWM converter 1 comprises self arc- distinction type semiconductor element GTO and diode D, and AC voltage of the converter can be controlled in magnitude and phase by PWM. Changing of forward and reverse conversion and magnitude of power at input and output of the converter can be controlled freely. ON and OFF gate signals are applied to the GTO from ON gate circuit 7 and OFF gate circuit 8 respectively, and when overcurrent occurs a gate signal command circuit 9 commands application of OFF gate signals. In this constitution, when GTO current becomes over interruptable value the breakage of GTO caused by application of OFF gate signal can be prevented.
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23 Feb 1981TL;DR: In this article, a d.c. converter with two transistors (22, 25) and an output transformer (21) is described, which can be operated from a low frequency a.k.a. voltage mains via an auxiliary full-wave rectifier (5 to 8).
Abstract: The invention relates to a d.c. to a.c. converter comprising two transistors (22, 25) and an output transformer (21). This converter also includes an auxiliary d.c. voltage source (43) and is provided with an auxiliary winding (40) of the transformer (21) which connects the base of one transistor (22) to the base of the other transistor (25). According to the invention, the combination of the auxiliary d.c. voltage source (43) and a control circuit of the two transistors (22, 25) comprises a current blocking means (44) such that the converter can be supplied with a pulsed d.c. voltage. Consequently, that converter can be operated from a low frequency a.c. voltage mains via an auxiliary full-wave rectifier (5 to 8), which does not need to have a high value smoothing capacitor.
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IBM1
TL;DR: In this paper, a flyback type DC to DC converter is used to correct load variations and feed forward to correct for line voltage variations in order to achieve a constant loop gain, where the output of the error amplifier is multiplied by a constant (112) and added to a signal proportional to line voltage.
Abstract: A constant loop gain is achieved in a flyback type DC to DC converter (102) by use of feedback to correct for load variations and feed forward to correct for line voltage variations. The feedback signal (103) and a reference voltage (Vr) are compared by an error amplifier (104). An output of the error amplifier is multiplied by a constant (112) and is added to a signal (107) proportional to line voltage. The resulting sum (113) causes modification of the slope of a ramp voltage (Vc) which is compared (105) to the voltage at the output of the error amplifier (104) to control the «on times of the converter switching devices.
01 Jan 1981
TL;DR: A 30 MJ superconducting magnetic energy storage system was installed in 1982 in Tacoma, WA, to act as a transmission line stabilizer as discussed by the authors, where two 6 MVA transformers and a 5.5 kA, + 2.5kV converter were connected the superconducted coil to the 13.8 kV bus and regulate the power flow between the coil and the three phase system.
Abstract: A 30 MJ superconducting magnetic energy storage system will be installed in 1982 in Tacoma, WA, to act as a transmission line stabilizer. Two 6 MVA transformers and a 5.5 kA, + 2.5 kV converter will connect the superconducting coil to the 13.8 kV bus and regulate the power flow between the coil and the three phase system. The design philosophy for the converter including its control and protection system is given in the paper. The converter has been tested with 10% overvoltage at no load, with 10% overcurrent at zero output voltage and with a watercooled resistive load of about 1 MW. These test results show that the converter will meet the expected full load operating conditions.