Showing papers on "Buck–boost converter published in 1969"

Buck-boost pulse-width-modulated line regulator

Abstract: An AC regulator controls the voltage applied to a load by using pulse-width-modulated correction signals. Any deviation of load voltage from that desired is sensed and converted to pulse-widthmodulated signals. These signals switch alternate halves of a secondary winding of a transformer connected in a buck-boost arrangement. The net voltage applied to the secondary winding is a function of the pulse-width modulation and a net correction voltage is coupled to the primary winding which is series connected between line and load. The invention also has application to line transient generation because of the overall high speed of response of the circuit.

Static converter with dc intermediate circuit for controlling the speed of a three phase motor

Abstract: A first controllable converter is connected to an electrical power supply source. A second controllable converter is connected to a three-phase electric motor having stator windings impressed by preenergizing current. At least one smoothing choke for controlling the speed of the motor is connected at one end to the first converter and at the other end to the second converter. A control circuit causes the voltage at the one end of the choke to follow the voltage at the other end of the choke.

Regulated static dc to dc converter start-up means

Abstract: A static DC to DC converter having an output converter stage comprising a full-wave bridge with an SCR in each of two adjacent legs of the bridge. The firing times of the SCR''s are controlled by a variable phase synchronous pulse generator controlled by an operational amplifier having one input connected to a reference voltage source and another input connected to feedback means across the converter''s output so that the converter''s output voltage is regulated. Means are provided for delaying, during start-up, the application of voltage to the pulse generator to prevent heavy current surges through the SCR''s. An overshoot voltage clipper is connected across the output of the operational amplifier.

Device in current converters

Abstract: In a static converter which includes a delay angle control device, a control amplifier for controlling the delay angle control device, and an arrangement for blocking the converter. In order to provide for rapid starting of the converter a limiting member for limiting the delay angle of the converter so as to limit the direct voltage of the converter is controlled by the output signal of the blocking device over a switch delaying circuit. A transient order device is also connected to the input side of the control amplifier to increase the input signal of the amplifier and the transient order device is actuated by the blocking means for the DC transmission line connected to the converter. An under-voltage sensitive device actuated by the voltage in an AC network connected to the converter is connected in parallel to the blocking device, and the two parallel devices are connected to the limiting member and the transient order device by an OR gate.

An electrical converter system employing a control converter for controlling the operation of a power converter

Abstract: A converter system utilizing a control converter operated during both the positive and negative current half cycles of the output voltage to initiate firing pulses for a power converter which can be operated in either a noncirculating current mode or a circulating current mode.

Self-oscillating voltage converter

Abstract: A self-oscillating voltage converter including a pair of complementary transistors connected in single-ended push-pull configuration without the use of a transformer. The first transistor is shunted by a piezo-electric two-terminal device in series with a relatively large capacitor, across which an output alternating voltage at the resonant frequency of the device is produced and fed back to both transistors through an R-C network.

High-speed ac/dc converter

Abstract: AN IMPROVED HIGH-SPEED AC TO DC CONVERTER IS DISCLOSED WHICH HAS A RESPONSE TIME SUPERIOR TO THAT OF EXISTING CONVERTERS. THAT IS, THE DC OUTPUT OF THE CONVERTER REACHES ITS STEADY STATE VALUE IN A SHORTER TIME PERIOD THAN IS POSSIBLE WITH EXISTING AC TO DC CONVERTERS. THE IMPROVEMENT IN RESPONSE TIME IS ACHIEVED BY A UNIQUE CIRCUIT ARRANGEMENT INCLUDING A PLURALITY OF OPERATIONAL AMPLIFIERS. BY MEANS OF THE UNIQUE ARRANGEMENT, A COMPARATIVELY LARGE VOLTAGE PROPORTIONAL TO THE INPUT VOLTAGE IS ADDED TO THE DC OUTPUT INITIALLY AND UNTIL THE DC OUTPUT REACHES ITS STEADY STATE VALUE. THE LARGE VOLTAGE ALLOWS A CAPACITOR IN FILTER CIRCUIT TO CHARGE MORE RAPIDLY THEREBY SIGNIFICANTLY DECREASING THE TIME REQUIRED FOR THE DC OUTPUT VOLTAGE TO REACH A STEADY STATE VALUE. FURTHERMORE, THE CONVERTER OF THE PRESENT INVENTION FEATURES INCREASED ACCURACY AND PRECISION.

Method and apparatus for testing a-to-d converters

Abstract: A method and apparatus for testing an A-to-D converter by applying to the A-to-D converter a DC test signal whose amplitude is varied and which is modulated by an AC signal. The output digital data from the A-to-D converter is applied to a D-to-A converter and then displayed for monitoring the distortions of the A-to-D converter.

Converter arrangement for alternating and direct current operation

Abstract: A converter arrangement is provided which can be set to operate both as an inverter and as a rectifier and wherein the converter elements are constituted by thyristors which are liable to damage by sharply rising voltages thereon brought about by overcurrent conditions when the converter is operating as a rectifier. To protect the converter elements against damage in such event, means are provided for changing over the operating mode of the converter from rectifier to inverter operation and to also cut off the converter operation completely after a predetermined time delay if the overcurrent condition persists.

Power converter with regulated output

Abstract: APPARATUS FOR REGULATING DIRECT CURRENT POWER FROM AN UNREGULATED DIRECT CURRENT POWER SOURCE COMPRISING A CONSTANT FREQUENCY PILOT OSCILLATOR AND AT LEAST ONE STABILIZING UNIT. EACH STABILIZING UNIT INCLUDES SWITCHING MEANS FOR INTERRUPTING THE CURRENT FROM THE DIRECT CURRENT POWER SOURCE DURING A PORTION OF EACH CYCLE WHICH IS CONTROLLED BY THE PILOT OSCILLATOR, AND INCLUDING A RECTIFYING CIRCUIT AND A FILTERING CIRCUIT FOR REFINING THE REGULATED OUTPUT FROM THE SWITCHING MEANS. THE OUTPUT OF THE FILTERING CIRCUIT IS MONITORED BY A COMPARISON DEVICE, WHICH GENERATES A SIGNAL, REPRESENTATIVE OF THE VARIATIONS OF THE OUTPUT VOLTAGE FROM A PREDETERMINED LEVEL AND, WHICH SIGNAL IS COUPLED TO AN ERROR SIGNAL GENERATOR TO PRODUCE AN ERROR SIGNAL. THE ERROR SIGNAL, WHICH IS REPRESENTATIVE OF THE OUTPUT OF THE COMPARISON DEVICE, AND THUS THE OUTPUT FROM THE FILTERING CIRCUIT IS THEN FED FROM THE ERROR SIGNAL GENERATOR TO AN ENAB LING DEVICE. THE ENABLING DEVICE GENERATES A SIGNAL TO CONTROL THE CONDUCTION AND NONCONDUCTION INTERVALS OF THE SWITCHING DEVICE, AS A FUNCTION OF THE VARIATION OF THE OUTPUT VOLTAGE FROM A PREDETERMINED VALUE.