Abstract: An alternating current input to direct current output power supply providing a regulated constant voltage or constant current output and incorporating a switching-mode preregulator and a postregulator. Regulation is primarily obtained by means of a bidirectional switching element operated at a relatively low voltage and the alternating current voltage output from the switching element and an associated power transformer is applied to a rectifying voltage multiplier to produce a high voltage output. A series-pass output regulator, is controlled by negative feedback derived from the output circuitry and negative feedback from such regulator controls the switching element.

Abstract: An apparatus for converting a complex AC voltage wave to an equivalent DC value which is a measure of its true RMS value and which may then be read on an accurate indicating device such as a digital voltmeter, incorporating thermal converters and operational amplifiers in a temperature-compensated configuration The apparatus maintains a portion of an unknown AC voltage wave, which is thermally converted into a DC voltage, substantially equal to a DC reference voltage A portion of a DC output voltage is also maintained substantially equal to the DC reference voltage Since the proportioning means for the complex AC voltage wave and the DC output voltage is the same, the true RMS value of the complex AC voltage wave is equal to the DC output voltage

Abstract: Current applied to a load by means of a first voltage is disabled by control means in response to a change of a second voltage by a predetermined value. The control means is powered by the first voltage and includes two stages, a first for detecting a change of the second voltage and the second responsive to such change and powered by the first voltage for generating a signal for disabling the current applied to the load.

Abstract: An accessory unit for use with an engine powered vehicle having a conventional electrical system including a battery, voltage regulator and a dynamo which in normal operation supplies DC power to the vehicle electrical system, including switches adapted to isolate the dynamo from the vehicle electrical system, and means for boosting the DC voltage dynamo output and converting it to a constant frequency AC voltage. An outlet receptacle is provided to accept jacks from power tools, appliances or the like having constant frequency AC voltage power requirements. The outlet receptacle voltage is monitored and the dynamo field current is adjusted in response to variations therein to control the dynamo voltage and amperage input to the unit. In another embodiment of the invention, a secondary coil is provided on the transformer along with conventional rectifying means to step down and rectify the increased AC output voltage. Voltage regulator means is provided to sense variations in this low voltage DC secondary output and control the dynamo field current in response to variations therein to maintain a desired dynamo output voltage and amperage. Additionally, the vehicle battery may be charged by an output from the rectified low voltage secondary output of the transformer.

Abstract: An unusually compact and efficient high voltage power supply of the saturable-core and resonant-secondary type is achieved by combining a high voltage secondary winding and a resonant-secondary winding into one relatively efficient yet relatively low voltage secondary winding and by coupling this secondary winding to a voltage doubling rectifier circuit. A high voltage capacitor is used to extract a high voltage alternating current signal from this same secondary winding so that a peak D.C. output voltage whose magnitude is 11/2 to 2 times the peak-to-peak A.C. output voltage of the secondary winding may be achieved. By eliminating the need for multiple windings, this power supply can compact all of its elements, including the rectifier circuit, into a space that is substantially smaller than the space occupied by the transformer alone of a conventional power supply.

Abstract: DC voltage is coupled through an active voltage regulator to a voltage inverter to develop a precisely controlled AC output voltage. Feedback from the inverter output supplies requisite operating bias to the regulator only when the inverter develops an output voltage, thus rendering the regulator inoperative in the absence of an output voltage as on the occurrence of a short circuit at the load, thereby affording short circuit protection for the DC to AC converter.

Abstract: The circuit of the present invention is operative to produce an output signal having a plurality of signal levels and which automatically switches therebetween in response to a remotely sensed voltage signal. The circuitry of the present invention includes a current source operative to provide a known quantity of current which is passed through a resistive means to establish the output voltage signal. A current sink is provided in parallel with the resistive network and is selectively operative or inoperative to vary the amount of current flowing from the current source through the resistive network. Means are provided to sense the remote voltage and to control the current sink in response to the sensed voltage. The sensed voltage is also applied to the resistive network through a uni-directional current flow device to establish within the resistive network a voltage which corresponds to the sensed voltage whereby a decrease in the sensed voltage will automatically produce a corresponding decrease in the voltage output signal.

Abstract: A current fed inverter circuit operating in a time-sharing mode to supply A.C. output voltage to a load from a D.C. voltage source. Typically the load may be inductive, for example, an induction heating work coil, in which case a capacitor is connected across it to correct the power factor. So-called ''''time-sharing'''' capacitors are connected in series between the solid state switching devices of the inverter circuit, which are typically thyristors, and the electrical load. Under all output voltage conditions up to and including the preferred full load voltage operating condition the phase displacement between the output voltage and output current is such that the current always lags the voltage thus establishing a lagging phase angle operation. The time-sharing capacitors under ideal conditions are dimensioned such that with the full load current flowing at the output of the inverter circuit, the peak voltage developed across each time-sharing capacitor is approximately equal to the peak load voltage at the normal output frequency.

Abstract: A power supply which yields one or more constant output voltages independently of the input voltage level and irrespective of whether the energizing source is AC or DC, and irrespective of the frequency of the source. The input voltage energizes a variable duty cycle generator, the duty cycle of which is controlled by a variable off-time oscillator. The off time of the oscillator is established by a reference voltage and the system output voltage so that the output voltage is regulated irrespective of the input voltage.

Abstract: A speed controlled electric traction system comprising a direct current compound electric motor having means for controlling its speed from zero up to its maximum value with a minimum energy loss on the speed regulation. The means for controlling the speed of the motor comprise a rheostat in series with the shunt field windings of the motor and linked to a voltage controller in series with the series field winding and armature of the motor. The voltage controller can be one of a number of different types such as a rheostat, a potentiometer allied to a controlled rectifier or a potential dividing switch arrangement acting on the individual cells of the battery. The voltage controller of the armature circuit and the rheostat of the shunt winding are linked together and to an operating member such that as the motor is controlled from standstill the maximum voltage is applied to the shunt winding as the voltage on the armature winding is progressively increased up to a maximum value, and thereafter the voltage on the armature winding is maintained at a maximum while the voltage on the shunt field winding is progressively reduced until the motor attains its maximum speed.

Abstract: When voltage variable capacitor (VVC) diodes are used to tune the r-f circuits of receivers, a potentiometer is usually used as the mechanically operated source of variable voltage To avoid tuning problems associated with power line variations, or receiver circuit conditions that cause voltage variations, a well regulated source of d-c voltage is used to supply the control circuits The improvement disclosed here involves applying an automatic frequency control (AFC) voltage, also known as automatic fine tuning (AFT) voltage, to the control circuit of the voltage regulator Since the tuning voltages are obtained from the regulated source, the magnitude of regulated voltage will be controlled by the AFC voltage If the polarity of AFC action is set to minimize the AFC error voltage, automatic frequency control or fine tuning is achieved

Abstract: An arrangement for maintaining a constant voltage at a variable load includes an adjustable direct current voltage source having a positive and a negative pole. A voltage regulator is provided which has comparator inputs and a triac which is connected to the voltage source for adjusting the voltage source in response to changing values of voltages applied to the comparator inputs. Four similar conductors are provided which are equal and adjustable in length and which together form a bridge circuit for maintaining the load voltage constant independently of the conductor lengths. To accomplish this, the first conductor is connected between the positive pole of the voltage source to one terminal of the load, the second conductor is connected between the negative pole of the voltage source and to other terminal of the load, the third conductor is connected between the one terminal of the load and the one comparator input of the voltage regulator, and the fourth conductor is connected between the other terminal of the load and the other comparator input of the voltage regulator. A voltage equalizer is interposed between the third conductor and the one comparator input to equalize the voltages applied to the differential inputs of an operational amplifier whose output controls the triac. A full wave rectified voltage derived from the main alternating current power source is supplied to one of the differential inputs of the operational amplifier and a sawtoothed reference voltage is applied to the other differential input, these two fluctuating voltages being superimposed on the direct current voltages supplied by the third and fourth conductors.

Abstract: A saturable reactor is excited by the output of an AC generator, the field of which is controlled by a current exciting the reactor Since the exciting current of the saturable reactor is proportional to an input voltage, the ratio of the output voltage to the output frequency of the AC generator is maintained constant

Abstract: An E.H.T. voltage supply system comprising a relatively high voltage d.c. supply having a relatively high output impedance and low output capacitance, a second voltage supply arranged to charge a storage capacitor, and switch means for discharging the capacitor through the primary winding of a transformer to produce a higher voltage of the secondary winding which is combined with the voltage provided by the first voltage supply means.

Abstract: A multijunction thermal convertor of the differential type is employed to obtain energy balance between a D.C. input voltage and an A.C. input voltage in order to determine the RMS value of the A.C. voltage. Amplified feedback from the output of the convertor is used to maintain this balance, by controlling the gain of an amplifier in the A.C. input. The value of this gain in relation to the D.C. input voltage is a measure of the desired (RMS) A.C. input voltage, and such value is expressed as a D.C. output voltage. The system has greater accuracy than previous systems for achieving a similar measurement.

Abstract: The present disclosure relates to a converter for producing a stabilized output D.C. voltage from an input D.C. voltage. The stabilization of the output voltage is carried out by means of pulse width regulation of a rectangular wave voltage obtained from the chopped input voltage. The level of the output voltage is sensed by means of a sensing device and compared with a reference voltage, whereby an error signal is obtained. A blocking oscillator device is on one hand triggering a driving stage which controls the chopping of the input voltage, and is on the other hand delivering a saw tooth voltage in order to add the same to the error signal. The sum of said signals is fed to a pulse width control device for controlling said pulse width regulation.

Abstract: An automatic DC voltage regulating system includes an automatic AC voltage regulator whose output impedance is inductive. Voltages respectively in phase with the voltages of an input and an output winding of this AC voltage regulator are combined by means of a pair of additional windings magnetically connected with the input and output windings and themselves interconnected in series. A series circuit of a resistance and a capacitor, for example, is connected to the aforesaid additional windings so as to cause a desired phase lag to the above obtained resultant of the input and output voltages of the AC voltage regulator. The output voltage of this resistance-capacitor series circuit is applied via a transformer to a rectifier connected in tandem with the AC voltage regulator, thereby controlling the gate of at least one thyristor included in the rectifier in accordance with variation in the value of the load current. There are also disclosed herein several other examples of the automatic DC voltage regulating system of the invention.