Abstract: A load tap changer (LTC) having a plurality of windings is coupled to one of the primary and secondary of a power transformer in order to regulate the output voltage of the transformer. The LTC includes a plurality of taps physically and electrically connected to and along the windings and a contacting element is selectively moved along the taps to increase or decrease the output voltage of the transformer. The power transformer and the LTC windings are placed in a main tank and the taps are placed in an LTC tank. The temperature in the main tank and the temperature in the LTC tank are monitored by means of first and second temperature probes whose outputs are used to sense the temperature differential (TDIFF) between the main tank and the LTC tank and to determine if the LTC tank temperature exceeds the main tank temperature for a period of time exceeding a specified time period. Also included is circuitry for sensing the rate of change of TDIFF and determining if it exceeds a predetermined value.

Abstract: A display apparatus having a high voltage FBT driving circuit includes a transformer having a primary and a secondary coil, a high voltage detector to detect an output voltage of the secondary coil, a high voltage compensator to output a high voltage compensating signal based on the detected voltage, a DC voltage controller to adjust a DC voltage according to the high voltage compensating signal and to output the adjusted DC voltage to the primary coil, a horizontal deflector to generate a horizontal deflecting pulse based on the DC voltage, a turns ratio adjuster to adjust a turns ratio of the primary and secondary coils, and a controller to control the turns ratio adjuster so as to make the output DC voltage higher than a lower limit when the frequency of a received horizontal synchronous signal is lower than a predetermined reference level.

Abstract: Under load tapchanging voltage regulators with source and load connections, series and shunt transformers, switching devices for causing selectable levels of electric power to flow in either direction between the series and shunt transformers, and tapchanger controls for sensing the voltage at said load connections and causing the switching devices to select proper electric power flows so as to maintain desired voltages at the load connections.

Abstract: Apparatus for regulating an electric voltage in at least one of electric supply networks and consumer units. The apparatus includes a regulating transformer arranged between a network node and at least one end consumer. The regulating transformer utilizes a primary winding and a regulating winding which includes switchable partial windings and a high leakage impedance. The transformer conducts a nominal current. A transfer switch switches the partial windings of the regulating transformer. Adjacent tappings of the partial windings are adapted to short circuit such that, in an event of the short circuit, the high leakage impedance limits a ring current which results from the short circuit to an order of magnitude of the nominal current. The regulating transformer produces both an increase in voltage and a decrease in voltage at the end consumer. This abstract is not intended to define the invention disclosed in the specification, nor intended to limit the scope of the invention in any way.

Abstract: A thyristor transformer has a mechanical tap selector and a diverter switch with thyristors. The tap selector is mounted in the oil-filled housing or tank of the transformer and the diverter switch is mounted in a separate housing laterally attached to the tank.

Abstract: The invention relates to a method for regulating the electrical voltage in electrical supply networks and/or consumer units and a device for carrying out said method. A regulating transformer (3) is inserted between a network node (1) in the supply network and/or consumer unit and at least one end user (2). The regulating transformer (3) comprises a high leakage impedance, which limits the ring current to the order of magnitude of the nominal current, in the case of a short-circuit between adjacent tappings (5) of the partial windings (4). The regulating transformer further comprises a transfer switch (7), to switch the partial windings (4).

Abstract: A power regulation system is coupled to an AC power source outputting an input voltage. The system has a first transformer to receive the input voltage and generate a control voltage. The system also has a second transformer that has a primary coil and a secondary coil. The primary coil and secondary coil of the second transformer are electromagnetically coupled to each other and so arranged that when the control voltage from the first transformer is applied to the primary coil, an output voltage is generated between a first end and a second end of the secondary coil, wherein the output voltage is substantially 180° out of phase from the input voltage so as to generate an effective voltage applied to the load, and wherein the effective voltage is less than the input voltage and substantially equals to the difference between the input voltage and the output voltage, resulting a reduction in power consumption of the load.

Abstract: A power regulation system is coupled to an AC power source outputting an input voltage. The system has a first transformer to receive the input voltage and generate a control voltage. The system also has a second transformer that has a primary coil and a secondary coil. The primary coil and secondary coil of the second transformer are electromagnetically coupled to each other and so arranged that when the control voltage from the first transformer is applied to the primary coil, an output voltage is generated between a first end and a second end of the secondary coil, wherein the output voltage is substantially 180° out of phase from the input voltage so as to generate an effective voltage applied to the load, and wherein the effective voltage is less than the input voltage and substantially equals to the difference between the input voltage and the output voltage, resulting a reduction in power consumption of the load.

Abstract: A hybrid tap-changer for delivering AC power to a load in which a high-power tap-changing transformer with full range of adjustment but limited resolution is combined with a low-power electronic converter of limited range but high resolution to provide a tap-changing transformer with high resolution.

Abstract: A limited-angle power flow transformer implements power flow control in a transmission line of an n-phase power transmission system, where each phase of the power transmission system has a transmission voltage. The transformer has n primary windings, where each primary winding is on a core and receives the transmission voltage of a respective one of the phases of the power transmission system. The transformer also has m secondary windings on the core of each primary winding for a total of m*n secondary windings, where m is less than n. Each secondary winding has a voltage induced thereon by the corresponding primary winding. For each phase, m secondary windings are assigned to the phase. Each assigned secondary winding for the phase is from a different core. For all phases, the secondary windings are assigned from the cores in a balanced manner. For each phase, the secondary windings assigned to the phase are coupled in series for summing the induced voltages formed thereon.

Abstract: A voltage regulator apparatus comprises a transformer having a primary winding and a secondary winding, a plurality of further windings selectively connected to one of the primary winding and secondary winding, and a plurality of solid state selectors respectively coupled to each of the plurality of further windings to one of i) connect the further winding in series with the primary winding or the secondary winding and ii) bypass the further winding.

Abstract: A power controlling unit of the invention includes a power transformer: having a primary side connected to an Alternating-Current power supply source; and a secondary side having an end side provided with a terminal connected to an end of an object whose power is to be controlled, and the other end side provided with a plurality of voltage taps. A switching part is disposed between the plurality of voltage taps and the other end of the object. The switching part selects one from the plurality of voltage taps in order to connect the one to the other end of the object. A storing part stores output values for the object and switching patterns which correspond to the output values respectively. Each of the output values is set correspondingly to a unit of control consisting of a plurality of cycles of the source. Each of the switching patterns defines a voltage tap that should be selected if any in each of the plurality of cycles in order to achieve the corresponding output value.

Abstract: A static voltage regulator consists of a booster transformer, a regulator transformer, an electronic switching system and a control system. The booster transformer includes a booster primary winding and a booster secondary winding. The booster secondary is provided in series with the input and output terminals of the regulator so as to produce an output voltage. The regulator transformer includes a regulator primary winding and a regulator secondary winding. The regulator primary is electrically coupled to the output. The electronic switching system is coupled between the regulator secondary and the booster primary for providing a voltage to the booster primary. The control system includes a voltage sensor for sensing a voltage at the input, and a gating system coupled to the switching system for switching the output voltage in response to changes in the sensed input voltage.

Abstract: Autoranging power supply apparatus may comprise a power output section having a plurality of pairs of output terminals, each of which has a maximum voltage and current rating. A switching network associated with the power output section connects and disconnects the plurality of pairs of output terminals to the external load. A control system connected to the switching network operates the switching network in response to changes in the impedance of the external load to connect and disconnect to the external load selected ones of the plurality of pairs of output terminals of the power output section to compensate for impedance variations in the external load and to prevent from being exceeded the maximum voltage and current ratings for each of the plurality of pairs of output terminals.

Abstract: A regulator is provided for establishing asymmetrical voltage increase/decrease capability between an input node and an output node for enhanced regulation of either a voltage sag or a voltage swell within a utility system. The regulator includes an autotransformer having an input tap coupled to the input node of the regulator and an output tap coupled to the output node. The regulator further includes an electronic tap changer system coupled to the winding of the autotransformer. Together, the autotransformer and the electronic tap changer system provide the regulator with its asymmetrical voltage increase/decrease capability between the input node and the output node thereof. The regulator can be configured for voltage increase only, voltage decrease only, or both, provided an asymmetrical voltage increase/decrease capability is defined.

Abstract: In a method and a device for continuously adjusting, within a certain adjustment range, the turns ratio between the primary winding and the secondary winding of a power transformer provided with at least one regulating winding, a first tap is switched on during a portion of a cycle of the alternating voltage of the transformer and a second tap is switched on during another portion of the cycle of the alternating voltage. For this purpose, the device comprises electronic switches in the form of thyristors or transistors.

Abstract: An electric adjuster is so designed that, in order that an a.c. power supply or an a.c. signal as an input is arbitrarily adjusted or converted with high efficiency and outputted, the ratio of winding of a transformer can be arbitrarily adjusted or continuously adjusted. Thus the output voltage is automatically adjusted to become constant.

Abstract: A power converter for converting shore power voltage, phase, and frequency for shipboard use includes a variable inductance input transformer that can be connected to the shore power. The primary windings of the transformer have a plurality of taps, and a respective computer-controlled switch is connected between adjacent taps to selectively establish a closed circuit or an open circuit between the taps and thereby configure the primary windings as a low or high voltage "delta" or "wye", as appropriate for the shore power voltage. The output of the input transformer is sent to a variable speed drive, then to an output transformer, and thence to the distribution bus of the ship. A voltage regulator regulates the output voltage of the output transformer. If desired, a phase selector can be provided between the shore power and input transformer to establish the phase characteristics (i.e.

Abstract: A solid state voltage regulator and methods therefore are shown to include a transformer having a secondary coil, the secondary coil having a plurality of taps. A first solid state switch is connected between the regulator output and a first tap. The first switch need only have the capability of being turned on in response to a gate signal. A second solid state switch is connected between the regulator output and a second tap. The second switch has the capability of being turned on and turned off in response to gating signals. The output voltage resulting from the second tap is greater than the first tap. A controller, connected to the input, the output, the first switch and the second switch, senses the voltage present at the regulator input and output and generates gating signals in response to the sensed voltage. The voltage regulator may include several switches similar in construction and operation to the first switch.

Abstract: A tap changing circuit has each tap of a power transformer connected with a selector vacuum switching cell. The odd numbered cells and the even numbered cells are connected to respective sides of a load switch each including a further vacuum switching cell. The sides are bridged by a transition inductor or resistor.

Abstract: In an autotransformer of a single-phase three-wire system or a single-phase two-wire system, plural sets of main coils connected with input terminals are phase-wound on a single-phase core-type core, and further, between the ends of the main coils, plural sets of excitation coils mutually connected in series to wind on the single-phase core-type core are connected by plural combined connections. Further, plural sets of thyristors controlled ON/OFF by using the value measured by a voltage sensor connected to the aforementioned input terminals are provided between the aforementioned ends and the exciting coils. Therefore, the circuits are automatically changed in response to the increase and decrease of the input voltage, with a result that a load is not ill influenced so that the voltage value is always output within the predetermined range.

Abstract: In a compressor for adjusting a cooling power such that a piston integrally formed with an oscillator according to the oscillation of said oscillator adjusts the amount of refrigerant absorbed into a cylinder, a cooling power controller for the compressor which can control the cooling power by varying the power itself to change the operation state of the compressor for controlling the temperature of a refrigerator or an air conditioner, includes a power source for varying input alternate power to output the same through a plurality of secondary ports, an applied voltage controller for selecting the secondary port voltage of the power source to control the cooling power of the compressor, and a comparator for comparing a predetermined temperature with the actual temperature of an heat exchanger to control the applied voltage controller.

Abstract: A tap changing system for operation with a transformer and featuring a special group of gate-controlled electronic devices that operate as a circuit breaker and recloser such that, after half-cycle of short-circuit current, said special group is transferred to the OFF-state, whereby the tap changer winding is open circuited; the advantage being that only the special group of devices need be rated to sustain short-circuit conditions; a further feature is the concept of Discrete-Cycle Modulation (DCM) whereby tap voltage magnitudes are obtainable in increments intermediate the physical tap winding voltage magnitudes.

Abstract: A changeover switch for a tap changer including a pair of load switches. A diverter switch allows load to be diverted along a second path when its associated main switch is opened or closed. An auxiliary circuit has an auxiliary switch and a varistor connected in parallel across the secondary of a transformer. When the auxiliary switch is opened the varistor impedance is reflected onto the primary of the transformer which causes the current in the main switch to divert through the diverter switch so that the main switch can be opened or closed with substantially no load on it.

Abstract: An uninterruptible power system has a transformer with a primary connected to input terminals, a secondary connected to output terminals, a static switch connected between the input terminals and the primary, and an auxiliary primary connected to an inverter which is supplied by a battery to provide output voltage to the output terminals when a main AC power system connected to the input terminals has failed. The primary has multiple taps at different voltage levels and a buck-boost winding. The taps of the transformer are switched and the buck-boost winding is controlled to provide either buck, boost, or pass-by to allow control of the output voltage from the transformer to within a few percent of a desired voltage level despite large changes in the input voltage.

Abstract: An electric device is provided as an interface between a permanent power source and an electrical appliance for maintaining the appliance, or a component thereof, in an operative state during a momentary power failure. The electric circuit includes an auto-transformer for increasing the induced back electric magnetic field voltage which is present in the line voltage of the permanent power source during a momentary power outage. The auto-transformer increases the induced back electric magnetic field voltage to a voltage level which is sufficient to maintain digital clocks or other low power-requiring components incorporated in an electrical appliance in an operative state during a momentary power outage.

Abstract: A co-controller provides communication between a standard voltage regulator controller and an LTC transformer, to enable the standard controller to be used in the operation of the LTC transformer. The co-controller generally consists of an interface circuit and a control circuit. The interface circuit receives status signals pertaining to the operation of an LTC transformer, as well as control signals from a voltage regulator controller, and buffers these signals for presentation to the control circuit. The control circuit is microprocessor based, and modifies the input signals from the interface circuit to provide the appropriate control signals required for the operation of the LTC transformer. The control circuit also implements a number of functions not available through a standard controller, such as current balance paralleling, overvoltage protection and correction for faults.

Abstract: Disclosed is an End-Turn Solid-State Switching (ETSS) transfomer tap which makes use of a high-speed solid-state switching network to select either the end-turn lead or one of a number of non-isolated taps on a transformer regulating winding, and connects the selected tap to, while disconnecting the previously selected tap from, a single output conductor carrying the transformer load current. ETSS effectively changes the reference to one of the possible taps interfaced to a solid-state switching network. The same transformer regulating winding connected to ETSS can also be connected in series with a slow-speed mechanically-switched tap-changer (LTC). ETSS selects one connection point on the regulating winding while LTC operation selects the second point. A difference voltage is produced, depending on the number of turns between the ETSS selected tap and the LTC selected tap. The sign of the difference in voltage depends on whether the ETSS selected tap is higher or lower than the LTC selected tap.

Abstract: A system and method for coordinating shunt reactance switching in a system with a transformer having a primary voltage and a secondary voltage for supplying low voltage power to a load. Voltage and power meters are provided for measuring the primary voltage and the reactive power flowing to the load. A programmable logic controller receives as one set of inputs measurements of primary voltage and reactive power flowing to the load, and as another set of inputs, predetermined ranges establishing high and low limits for the primary voltage and the reactive power. Based on these inputs, the programmable logic controller connects or disconnects at least one shunt reactance to maintain the load voltage substantially constant.

Abstract: A high frequency power supply for supplying a yielding current through a choke to a welding station including an electrode element and a workpiece element, wherein the power supply includes a transformer means for creating a first current pulse in a first secondary winding and a second current pulse in a second secondary winding and means for connecting said secondary windings to pass said current pulses through said choke and across said elements.

Abstract: An AC power regulator having a tap changer. The regulator comprises a transformer having taps and thyristors connected with the taps, respectively. The regulator further includes rectifiers, comparators having hysteresis and comparing the output signals from the rectifiers with a reference voltage, a priority processing circuit for selecting the signal to which the highest priority is given out of the output signals from the comparators, firing circuits for firing the thyristors, respectively, and zero voltage-detecting circuits for detecting the voltages between the terminals of the thyristors. When the detected voltages are all nonzero, the conducting thyristor is switched to the next thyristor.

Abstract: An electronic system connected to a power transmission line having a fluctuating load for automatically providing increments of voltage to the line to supplement voltage losses from the load by sequentially connecting tapes on the windings of a transformer in response to changes in line current.

Abstract: A load is supplied by a transformer supplied via a voltage regulator and thyristor network. The thyristor network and regulator are simultaneously controlled to respond to changes in the load and in practice the thryistors respond rapidly and are re-adjusted as the regulator is inherently more slowly adjusted. The result is that the thyristors produce minimum reflected harmonics overall in the mains and an optimum power factor can be achieved for each power setting.

Abstract: A control circuit is provided for the output of a high frequency inverter of the type having an output transformer with a core, primary windings and a secondary winding with two sections for creating a first secondary current pulse of electrical current in one section when the primary windings magnetizes the core and a second secondary current pulse in the other of the secondary sections when the primary windings remagnetizes the core. By alternating switch means for passing current through the primaries to magnetize and remagnetize the core at a preselected rate the output current pulses are provided by the two sections of secondary windings. The control circuit of the present invention involves a modification of the output transformer secondary stage. A first auxiliary winding is connected to one of the secondary sections to create an auxiliary current pulse as the core of the transformer is magnetized.

Abstract: A voltage regulator for AC single phase and three phase systems. An output voltage is controlled by controlling a preset stepped addition to or subtraction from the input voltage. The controlled addition or subtraction is performed by a series injection transformer whose secondary is in series with the input voltage and whose primary is controlled by a microprocessor based switch matrix. The switch matrix imposes various voltage levels and phasing on the primary winding so as to produce a regulated system output voltage.

Abstract: Described is a novel power supply for generating a constant d.c. voltage from a variable a.c. voltage supply line. The power supply includes a plurality of switch circuits which monitor voltage levels on respective secondary windings of a power transformer and as voltage levels change, one of the plurality of switch circuits is selected to charge a capacitor which provides a range of d.c. voltages which are processed to provide the constant d.c. voltage.

Abstract: A protection circuit is provided for a tap switching line voltage regulator of the type which selectively switches in one of a predetermined number of taps on a winding of a transformer. The selective switching of the taps is controlled in response to the sensed load voltage to provide a regulated voltage to a load in the presence of a varying input line voltage. The tap switching line voltage regulator in response to the sensed load voltage controls the conductive state of a solid state series switching element in each of the switched tap lines. The protection circuit provides current limiting inductors in series with each of the solid state switching elements with all the inductors being wound on a common magnetic core. When switching from one tap to another tap, the tap switching line volage regulator in response to the sensed voltage operates to select an adjacent tap to the tap currently selected. Thus, tap switching proceeds in a sequential fashion up and down along the taps.

Abstract: An AC voltage regulator includes a transformer arrangement having a plurality of taps so that an input line voltage is passed to an output line with the output line voltage being determined by the nominal value of the input line voltage together with an amount contributed by the transformer. The device is switched by a network of relays one of which acts as a polarity reversal switch so that the voltage generated by the transformer is either added or subtracted to the nominal voltage. Further relays used in two series control the selection of the transformer tap. A transient suppression circuit uses a triac and resistor to communicate current from the input line to the output line with the triac gated into conduction on breaking of a relay contact. The input line voltage is measured by a comparator using a plurality of op-amps in series with the outputs therefrom passing through a logic circuit to control the relays.

Abstract: A power current regulator, in particular for airport lighting, includes transformers in series with intermediate taps on their secondary windings staged a various different numerical weights. In each case, one of said taps is selected by a latch memory (MV) preceded by an up/down counter (CD). These circuits are actuated by a control circuit as a function of the current detected by a current transformer (TIC) connected in series with the load.

Abstract: An uninterruptible power supply comprising a regulating transformer including output circuitry for connection to a load, first input circuitry for coupling a reserve AC voltage source to the regulating transformer and second input circuitry for coupling a primary AC voltage source to the regulating transformer, the second input circuitry comprising a plurality of winding taps, with each of the taps including a tap switch coupled to the primary AC voltage source.The uninterruptible power supply also includes a voltage control monitor for monitoring the voltage of the primary source and, if the voltage is outside a predetermined maximum allowable range, opening all of said tap switches to isolate the primary source from said transformer, and, if said voltage is within said predetermined maximum allowable range, selectively closing one of said tap switches so that the voltage at the load is held within a predetermined range.

Abstract: A tap-switching circuit for automatically controlling the output voltage of a multi-tap transformer in response to a varying input line voltage and/or system load current demand, includes voltage sensing circuitry in parallel with both the transformer voltage outputs and a voltage comparator for sensing changes in the system load demand requirements. A voltage reference is provided for automatically generating a pre-selected voltage reference level signal for the line and/or system load requirements. Voltage comparison circuitry is operatively connected with the voltage sensing circuitry for generating an enable signal whenever the input line voltage and/or system load current demand requirements sensed by the voltage sensing circuitry falls below the pre-selected voltage reference level signal.

Abstract: An arrangement for controlling an A.C. voltage supplied to a load, such as a fluorescent lamp emitting germicidal ultraviolet radiation in a water-purifying apparatus. The load is connected to the secondary winding of a transformer, the primary winding of which has a number of taps which are selectively connectable to an exterior A.C. voltage source. An electronic control device is arranged in dependence on the magnitude of the terminal voltage of the exterior A.C. voltage source to automatically connect that tap which causes the voltage applied to the load to be of a predetermined value.

Abstract: Apparatus for converting relatively high, variable frequency, variable amplitude electrical power into substantially constant amplitude and substantially constant, relatively lower frequency power of a preselected waveform. The power source signal is divided into a number of varying amplitude, same frequency segments. The segment having the amplitude nearest that of the preselected waveform is transmitted by a switching network during each of many time periods. The switching network is preferably controlled by a microprocessor that senses the amplitudes of the segments and compares them to the desired waveform amplitude as a function of time. The microprocessor provides control signals to the switching network in response to the comparison. Because the low frequency output signal is constructed with reference to a memorized signal, the output signal is particularly stable in spite of variations in the power source signal.

Abstract: This invention concerns a procedure for controlling the type of arc in an electrical furnace (F), which comprises the monitoring (R) of the short circuit power of the network line (L) during a period of inactivity of the arc, whereby the value thus monitored is processed (B) to determine a primary voltage (V) to be maintained at a transformer (T2) supplying the electrodes of the furnace (F), and whereby the processing (E) combines fixed parameters (P) and at least variable parameters relating to:pre-set conditions of the arc (S),conditions of a substation tap changer (VAR),and line parameters (C) including at least the state of connection of banks of capacitors (C1-C2).The invention also concerns an arc furnace (F) which employs a procedure for controlling the type of arc according to the methods described herein.

Abstract: A thyristor circuit including a primary winding and at least one secondary winding and first and second bipolar thyristor switches connected across respective connections of the secondary winding. The first bipolar thyristor switch bridges N.sub.1 turns of the secondary winding, while the second bipolar thyristor switch bridges N.sub.2 turns of the secondary winding, wherein N.sub.2 is less than N.sub.1. The product between the maximum forward current of the second bipolar switch and the number of turns N.sub.2 is greater than the product between the latching current of the first bipolar thyristor switch and the number of turns N.sub.1 thereof. The second bipolar thyristor switch thus makes it possible to short-circuit the portion of the secondary winding bridged thereby, for operation as a switchable choke, e.g. in a reactive compensator, or as a variable power supply when supplemented by additional components.

Abstract: A dual programmable control time constant circuit is provided for a tap switching line voltage regulator of the type which selectively switches in a sequential adjacent one of a predetermined number of taps on a winding of a transformer. The dual programmable control time constant circuit includes a stepping counter and a first bistable device for determining how long a sensed signal representative of the voltage of the load circuit may be permitted to remain outside preset upper and lower limits before corrective action is taken. A second bistable device is used to reset the stepping counter when the sensed signal has changed so as to again fall within the preset limits for a predetermined time. The dual programmable control time constants provide for large variations in load characteristics with the minimum time required per tap change consistent with stable regulator operation. The surge current caused by excessive tap switching is reduced to prevent damage to the regulator and load components.

Abstract: A lag ballast for a high intensity discharge lamp includes a transformer providing voltage at either of two levels. Triacs tied to the transformer supply current at the desired voltage level through either of two inductances. The triacs are controlled by a comparison circuit so that a low voltage and high current are supplied to the lamp during startup and a lower current and higher voltage are supplied as the lamp approaches its normal operating temperature.

Abstract: Two sources of alternating current, such as taps of a supply transformer, e selectively switchable across a load by means of two circuit branches each provided with a main switch and a collateral network in parallel therewith, this network comprising a series combination of a protective resistor, an ancillary switch and a pair of antiparallel thyristors. The gates of the thyristors of each pair are interconnected by a firing resistor in series with a disconnect switch; each gate, furthermore, is connected to its own cathode through a reverse-poled diode which enables the ignition of the opposite thyristor upon closure of the disconnect switch when the proper polarity of the source voltage appears across the network in the closed state of the associated ancillary switch.

Abstract: A process for eliminating the disturbances related to fluctuations of the load in chopped power supplies comprising a magnetic circuit with a primary inductance (Lp) coupled to a secondary inductance (Ls), characterized in that it consists in automatically adapting the value of the secondary inductance (Ls) as a function of the voltage (Us) at the terminals of the load (X), so as to ensure total transfer of the magnetic energy for each period of the chopping frequency.

Abstract: A transformer has a primary and a secondary. The primary is supplied by a source and is divided into permanent and selectable turns. Switch circuitry is connected by taps to the segments to selectively energize or de-energize them. The secondary is connected by a rectifier and filter to a voltage regulator which supplies a constant voltage to a load. Circuitry senses the voltage drop across the voltage regulator and comparator circuitry compares the series regulator voltage drop to reference values. The comparator generates error signals whenever the voltage drop falls outside of a desired range above the drop-out voltage of the regulator. The error signal is transmitted to an up/down counter which correspondingly increases or decreases its count. The count of the up/down counter is decoded by switch control circuitry to open and close the appropriate switches S.sub.1 -S.sub.6 to energize the desired turns of the primary to bring the series regulator voltage drop back within the desired range.