Abstract: This invention relates to personal computers, and more particularly to personal computer power supplies for supplying electrical power to electrically operated components which manipulate or store digital data. The power supply has a controllable component for responding to the presence and absence of a low voltage direct current electrical signal by enabling and disabling the supply of electrical power to the data processing and storage components, and a signal generator circuit operatively connected with the controllable component and with an alternating current electrical main supply for controllably deriving from the main supply a low voltage direct current signal for delivery to the controllable component, whereby a user of the microcomputer may control energization of the electrically powered data processing and storage components by controlling the application of the low voltage direct current signal from the signal generator circuit to the controllable component.

Abstract: Circuitry and methods are provided for AC line synchronization of the firing means for phase-controlled thyristors in a DC motor speed control system. A line synchronization method and system is disclosed which eliminates zero offset in the phase command input function. This zero offset, which is cuased by motor counter EMF, occurs in prior art controllers which use zero crossings of the AC line voltages for line synchronization of thyristor firing. This invention provides line synchronization timing intervals of constant duration that terminate at the coincidence of AC line voltage and motor counter EMF with the coincidence being the latest time at which the particular thyristor being controlled is forward biased in the absence of current flow. Application to N-phase AC to DC converters for DC motor speed control is disclosed.

Abstract: A circuit for the provision of low-voltage inhibit by using a reset output of a regulator with the enablement of a reset signal to the microcomputer unit in response to a "key-on" signal and a reset condition of the switchable output of the regulator thereby providing an additional reset mode from the switchable voltage supply in the regulator that is gated out to reset the microcomputer unit only in response to a "key-on" condition and a reset condition from the switchable voltage output of the regulator.

Abstract: In the control method for a PWM converter according to the present invention, an upper limit value of an inphase component of an instruction voltage for controlling an AC/DC converter is prescribed, and in the region where the upper limit value is exceeded, the inphase component of the instruction voltage is controlled to be within the prescribed upper limit value by setting a reactive component value corresponding to the exceeding quantity. This makes it possible to offer a low priced, stable control method for a PWM converter.

Abstract: A power generating system (10) in accordance with the present invention includes a converter (14) for producing an AC output (16) including a fundamental and at least one harmonic of the fundamental; a frequency analyzer (18), having at least one input coupled to the AC output, for providing an analysis of a frequency spectrum of the AC output; a processor (36), coupled to the frequency analyzer, for calculating at least one switching frequency, each switching frequency being used for transforming a different harmonic within the AC output back to the fundamental; a controller (34), responsive to the at least one calculated switching frequency, for producing control signals at the at least one calculated frequency for transforming the at least one harmonic back to the fundamental; a separating filter (24), coupled to the AC output, for separating the fundamental and that at least one harmonic; at least one converter (30 and 32), coupled to the at least one harmonic from the converter and to the controller, eac

Abstract: Device for eliminating interference in a given electrical signal generated by one or several power switches. The device includes an electronic switch interposed on the line of propagation of the signal, a generator of a pulse of programmed duration controlling the operation of the switch, and a delay circuit coupled to receive the switching instruction from the interfering switch or switches for triggering the pulse generator at the moment when the power switching takes place so as to cause the switch or switches to open.

Abstract: A power supply for producing a single level D.C. output voltage in response to a 110 or 220 A.C. input voltage is disclosed. The power supply automatically selects a full wave diode bridge or voltage doubler configuration and provides series capacitors to filter the D.C. output voltage. The selection is controlled by a switch which responds to the charge on one of the output capacitors. Latching means are also provided to prevent the power supply from switching to the voltage doubler configuration once 220 volts is applied.

Abstract: Voltage regulation of a DC electrical power source having a generator with an exciter field coil for producing an AC output voltage which is rectified to produce a DC output voltage, is accomplished by producing voltage signals proportional to the AC output voltage of the generator and the current in the generator exciter field winding, and combining these signals to produce a control signal. An additional voltage signal proportional to the DC output voltage of the power source is compared to a DC reference voltage signal to produce a trim error voltage signal. The trim error voltage signal is combined with an AC reference signal to produce an additional control signal. These control signals are compared and the result of that comparison is used to control the current in the generator exciter field winding.

Abstract: A method and apparatus for operating a DC motor controller according to a first gain when the armature current of the DC motor is discontinuous, according to a second gain when the armature current is continuous, and according to a third gain when the armature current is in transition from the discontinuous to continuous conduction. The gains have proportional and integral terms and the integral term in the discontinuous and transition regions varies inversely to a current reference in the controller.

Abstract: An electric locomotive has two AC-DC converters which are connected in cascade, and a power factor controller is connected to one of the converters. Two automatic pulse phase shifters are provided for the two converters and controlled by a signal responding to a difference signal between a current flowing in the converters and a reference signal. One of the input signals of the automatic pulse phase shifter is regulated by a bias signal. The output from each of the automatic pulse phase shifters to each of the converters is switched when the measured speed of the locomotive exceeds a predetermined reference speed signal.

Abstract: A switched resistor regulator controls current flow through a resistor electrically connected to a load by varying the duty cycle of switching the resistor into electrical connection between of a power source and the load to regulate the power to the load. Both current and voltage regulation can be achieved. In a series switched configuration, current flow through a resistor in series with the load is controlled with current flow being maintained by a capacitor is parallel with the load when the resistor is switched off. In a shunt switched configuration current flow through a resistor in parallel with the load is controlled, with a capacitor parallel to the load also being used. In a hybrid configuration a shunt switched resistor is used while the current level to the load is changed by selecting one of several series resistors; a capacitor is also provided parallel to the load.

Abstract: A dual regulated DC power supply produces an output voltage which is the sum of a variable DC control voltage and a floating DC voltage. The control voltage, generated by a first differential amplifier having an inverted input coupled to the power supply output through a feedback scaling circuit, varies in inverse relation to the change in power supply output voltage. The floating DC voltage is produced by isolating, rectifying and filtering the output of an oscillator having a peak voltage controlled by an applied bias voltage. The applied bias voltage is generated by a second differential amplifier coupled to compare the control voltage with a selected reference voltage so that a change in control voltage causes a change in the floating voltage. The control voltage changes rapidly in compensating response to transient changes in power supply voltage while the floating voltage changes more slowly in compensating response to output voltage changes due to sustained load swings.

Abstract: The invention relates to a device particularly adapted for use with the power supply of a computer for controlling the regulating facilities in an electric high-power AC-DC converter of the power supply.This control device (D) comprises a regulation (CC) control comparator connected to the storage facilities (S) of the converter and receiving a reference voltage having a "nominal" value when the converter is normally powered by an AC network and receiving a portion of the output voltage from the converter, the output of said control comparator (CC) supplying an error signal to the regulating facilities (MR) of the converter. The control device also includes facilities (R) for supplying a variable reference voltage to the control comparator (CC) so that at the moment of recovery of the network following a cutoff, the voltage at the input of the filtering facilities (F) of the converter is, at the most, equal to the output voltage of the storage facilities (S).

Abstract: In a power supply circuit designed so that an AC voltage is applied to the primary side of a transformer, and that the voltage derived on the secondary side thereof is rectified and smoothed, arrangement is provided that the AC voltage applied to the primary side is subjected to switching at least twice in each half cycle thereof to insure that the current which flows on the primary side is timewisely divided, whereby the peak value of the current flowing on the primary side of the transformer is suppressed to a small level. Thus, it is possible to realize a substantial reduction of noises as a result of minimized dI/dt and current value and also to realize a substantial reduction of power loss as a result of minimized current value.

Abstract: A power converter utilizes an inverter operating at a frequency near 30 kHz to produce an RF voltage which is divided by a reactive voltage divider, one portion of the divider including a saturable reactor having a control winding which is driven by a negative feedback current from a level sensing circuit connected to the converter output. DC voltage is provided by a bridge rectifier and filter connected across the saturable reactor. The circuit is especially useful for supplying electrical power efficiently to instrumentation on multikilovolt transmission lines where a transformer cascade is used to conductively isolate apparatus operating at the potential of the transmission line from a ground level power source.

Abstract: A unity power factor converter capable of effecting either inversion (dc-to-dc) or rectification (ac-to-dc), and capable of providing bilateral power control from a DC source (or load) through an AC transmission line to a DC load (or source) for power flow in either direction, is comprised of comparators for comparing the AC current i with an AC signal i.sub.ref (or its phase inversion) derived from the AC ports to generate control signals to operate a switch control circuit for high speed switching to shape the AC current waveform to a sine waveform, and synchronize it in phase and frequency with the AC voltage at the AC ports, by selectively switching the connections to a series inductor as required to increase or decrease the current i.

Abstract: A power converter is disclosed which is used for converting an a.c. power to a d.c. power or vice versa, and which comprises a first converter unit operated at a variable control angle with phase advanced to an input a.c. source voltage, and a second converter unit operated at a variable control angle with phase lagged to the input a.c. source voltage and having a d.c. side terminal connected in series to that of the first converter unit. At least one additional converter unit having a d.c. side terminal connected in seriesto those of the first and second converter units is further provided in accordance with the invention. The additional converter unit is operated at its bypass mode or a fixed control angle corresponding to the maximum forward or reverse conversion limit. The power converter of the above-mentioned construction enables its output level to be controlled continuously over a wider range without degrading its electric property than the conventional power converter.

Abstract: Multi-stage current operated power supply including linear transformer coupled to AC power lines and provides positive and negative regulated output progressively charged during each half cycle of input current while maintaining ampere-turns balance.

Abstract: A direct current power supply for manual arc welding comprising a polyphase transformer, a polyphase rectifier system including triggered rectifier valves, and a control system therefor which comprises means for setting the output current level by adjustment of a reference signal, means providing negative feed-back of the output voltage and the output current, and means for adjusting the slope of the characteristic by adjustment of the proportion between the amounts of feed-back of the voltage and the current. The current level setting means and the slope adjustment means are linked with each other to provide automatically a desired correlation between the slope and the current setting.