Abstract: The present invention relates to an electromagnetically-countered system including at least one wave source irradiating harmful electromagnetic waves and at least one counter unit emitting counter electromagnetic waves which are capable of countering the harmful waves by such counter waves. More particularly, the present invention relates to generic counter units of various electromagnetically-countered transformer systems and to various mechanisms for countering the harmful waves by the counter units by, e.g., matching configurations of such counter units with those of the wave sources, matching shapes of the counter waves with shapes of the harmful waves, and the like. The present invention also relates to various methods of countering the harmful waves with the counter waves by such source matching or wave matching and various methods of providing such counter units as well as emitting the counter waves.

Abstract: A system for reducing power consumption in a power supply circuit including: a transformer including: a core; a first winding including a first end and a second end of a first wire wound on the core; a second winding including a first end and a second end of a second wire, wherein the second wire has a larger cross-section than the first wire and the second end of the first wire is connected to the first end of the second wire; an input electrically connecting the first and second windings to the power supply circuit; and an output for connecting to a load; and a controller connected to the transformer for controlling an output voltage at the output, wherein the output voltage is less than a supply voltage at the input, to reduce the power consumption of the load.

Abstract: A DC-to-DC converter includes two or more inductors coupled to a common core and two or more active switches, where at least one active switch is in an input current path. A controller operates the two or more active switches such that a DC input is driven through one or more of the two or more inductors to implement a power conversion operation.

Abstract: A switched-mode converter includes a first magnetic circuit including a first inductive element, coupled to at least one second inductive element and electrically coupled in series with the second element and with a first diode between a first one of two input terminals and a first one of two output terminals; a first switch coupled in series with a third inductive element between a second terminal of the first inductive element and a second input terminal, a common node between the first switch and the third inductive element being connected to one of the output terminals by a second diode; and a circuit capable of canceling the voltage across the first switch before its turning-on.

Abstract: A converter circuit includes first and second input terminals, first and second capacitors, the second capacitor having a first terminal connected to the second input terminal and a second terminal forming a positive voltage node, first and third semiconductor components connected in series between the first input terminal and the positive voltage node, the midpoint between the series connection forming a first node, and a series connection of a first inductive component, a diode and a second inductive component. The series connection is connected between the second input terminal and the node. The diode's polarity allows current to pass from the direction of the second input terminal. A second node is formed between the first inductive component and the diode, and a third node is formed between the diode and the second inductive component. A third capacitor is connected between the first input terminal and the third node.

Abstract: A sample-and-hold (SAH) current estimating circuit and a first switching power supply are disclosed. The first switching power supply provides a first switching power supply output signal based on a series switching element and a setpoint. The SAH current estimating circuit samples a voltage across the series switching element of the first switching power supply during an ON state of the series switching element and during a ramping signal peak to provide an SAH output signal based on an estimate of an output current of the first switching power supply output signal. The first switching power supply selects the ON state of the series switching element, such that during the ramping signal peak, the series switching element has a series current having a magnitude, which is about equal to a magnitude of the output current of the first switching power supply output signal.

Abstract: The present invention includes: a main switch Tr1 connected to two ends of a DC power supply Vi via a first primary winding 1a and a second primary winding 1b, connected to the first primary winding in series, of a transformer T1; a series circuit connected to the two ends of the main switch, and including a reactor L1, a diode D1, a smoothing capacitor Co and a hoist winding 1c connected to the second primary winding in series; a series circuit connected to the two ends of the main switch, and including a diode D2, a diode D3 and the smoothing capacitor; a control circuit 10 to turn on and off the main switch; a soft-switching circuit Da1, Tra1, La1, Ca1 to cause the main switch to perform a soft-switching operation each time the main switch turns on; and a switching control circuit 20 to switch the soft-switching circuit between operating and non-operating modes in accordance with the state of a load.

Abstract: An isolated power converter that includes, in one embodiment, a first magnetic core having a primary winding and a secondary winding around the first magnetic core. The power converter includes a second magnetic core having a first leg, a second leg coupled to the first leg, and a third leg coupled to the first and second legs, wherein a part of the third leg is equidistant from the first leg and the second leg. The power converter also includes a first winding encircling the first leg, a first end of the first winding coupled to the secondary winding, a second winding encircling the second leg, a first end of the second winding coupled to the secondary winding, and a third winding encircling the third leg, a first end of the third winding coupled to a second end of the first winding and to a second end of the second winding.

Abstract: A unidirectional DC-DC converter and method of control thereof. The converter includes a DC power-supply, a buck converter circuit having a first main switching element, a boost converter circuit having a second main switching element, a first snubber capacitor, a first inversely-parallel diode, a control device, and an output diode.

Abstract: A digital control switching power supply unit converts an input voltage into a desired output voltage using a digitally controlled pulse width modulation (PWM) signal according to a switching cycle. The power supply unit includes an analog-to-digital converter (ADC). The ADC converts a result of a comparison between an output voltage and a reference voltage to a digital signal during a conversion cycle. The ADC includes a circuit for outputting a phase difference between a switching cycle and the conversion cycle, and a delay circuit. The delay circuit generates a delay output current based on a result of the comparison and the phase difference and determines the conversion time delay according to the delay output current. The delay circuit also generates a delay reference current based on the reference voltage and the phase difference and determining the duration of the conversion cycle according to the delay reference current.

Abstract: The present invention provides a DC-DC converter including a first series circuit connected to both ends of a first switch and formed of a winding of a first transformer, a first reactor, a first diode, and a smoothing capacitor, a second diode connected to a connection point of a primary winding of the first transformer, the winding of the first transformer and the first switch, and to one end of the smoothing capacitor, a second series circuit connected to both ends of a second switch and formed of a winding of a second transformer, a second reactor, a third diode, and the smoothing capacitor, a fourth diode connected to a connection point of a primary winding of the second transformer, the winding of the second transformer and the second switch, and to the one end of the smoothing capacitor, a third reactor connected to both ends of a series circuit of a secondary winding of the first transformer and a secondary winding of the second transformer, and a control circuit which alternately turns on the first s

Abstract: A voltage regulator is provided that includes a plurality of buck-boost transformers each having primary and secondary windings. The secondary windings of the transformers are electrically disposed in series between a source and a load. Each transformer is controlled by a plurality of control switches configured to control the voltage across the primary winding of a corresponding transformer. A controller monitors the output voltage and generates control signals for the switches. The transformers generate different voltage level changes in between the source and load and the voltages across the primary windings are capable of assuming opposite polarities to enable scaling of resolution and range. The voltage regulator efficiently regulates power with relatively few or no moving parts and also partially protects the power switching components by removing them from the path of the load current thereby producing a device that is smaller in size, costs less and is more reliable.

Abstract: A method and an apparatus for calculating the number of turns per segment of a transformer coil winding which has a plurality of segments connected in series. The number of turns per segments is computed by assigning to segments predefined parameters related to customer requirements. Then a system of linear equations is automatically generated and the equations are simultaneously solved.

Abstract: In a multi-phase power converter, efficiency is increased and ripple reduced while maintaining transient response and dynamic performance improved by electrically coupling secondary windings of transformers or provided for inductors of respective phases such that current to a load is induced in each phase by current in another phase. Magnetic coupling can also be provided between phases using a multi-aperture core of a configuration which minimizes primary winding length and copper losses. Efficiency at light load is enhanced by controlling current in the series connection of secondary windings in either binary or analog fashion.

Abstract: An embodiment of a power-supply controller is operable to couple a first node of a first inductor to first and second reference nodes, the first inductor composing a first phase of a power supply and having a second node coupled to an output node of the power supply. The controller is also operable to couple a first node of a second inductor to third and fourth reference nodes, the second inductor composing a second phase of the power supply and having a second node. Furthermore, the controller is operable to uncouple the second node of the second inductor from the output node of the power supply. For example, where the first and second inductors are magnetically coupled, such a controller allows the power supply to operate as an uncoupled-inductor (UI) power supply in one mode, and as a coupled-inductor (CI) power supply in another mode.

Abstract: A method for operating a voltage regulator controller, for use in a voltage regulator including coupled inductors, is provided as follows. A first signal is generated for driving a first switch of the voltage regulator. A second signal is generated driving a first switch of the voltage regulator. The voltage regulator determines whether a light-load condition exists. Upon determining the existence of a light-load condition, adjusting the phase difference between said first and second signals so that the first and second signals are approximately in-phase.

Abstract: A negative capacitance is developed by configuring an inductor as two inversely or opposingly coupled windings having different numbers of turns and connecting a capacitance to a center tap between the two windings. The negative capacitance is developed on the side of the inductor having the winding with the greater number of turns.

Abstract: A booster circuit according to an embodiment of the present invention comprises: an input terminal; an output terminal; a common terminal; a transformation unit including first, the second, and the third windings, the windings wound in the same direction and connected in series; a first rectifier unit provided between the input terminal and a connection point of the first and the second windings; a second rectifier unit provided between the input terminal and a connection point of the second and the third windings; a first switching unit provided between one end of the transformation unit and the common terminal; a second switching unit provided between other end of the transformation unit and the common terminal; a third rectifier unit provided between a connection point of one end of the transformation unit and the first switching element and the output terminal; and a fourth rectifier unit provided between a connection point of other end of the transformation unit and the second switching element and the o

Abstract: A buck or boost converter, which includes a first inductor, a controlled switch, a main diode, and an output capacitor, also includes a snubber circuit to reduce losses. The snubber circuit includes a second inductor in a path in series with the switch and main diode of the converter, a series-connected resistor and diode connected directly in parallel with the second inductor, and a capacitance in parallel with the main diode and which can be constituted partly or entirely by parasitic capacitance of the main diode.

Abstract: A power supply system with a remote control circuit and a power supply system operation method are provided. The power supply system uses a remote control power supply device and a battery to provide a system with power, while the remote control circuit includes a first-resistor, a first-operational amplifier, a second-operational amplifier and a selection circuit. The first-resistor herein is coupled between the remote control power supply device and the battery. The first-operational amplifier detects the current passing through the first resistor so as to output a first control signal. The second-operational amplifier detects the battery voltage so as to output a second control signal. The selection circuit outputs one of the first control signal and the second control signal with a lower voltage and the output signal is served as a remote control signal to adjust the voltage of the remote control power supply device.

Abstract: A DC-DC converter is structured such that a main switching element has one terminal connected to one terminal of a DC power supply and has the other terminal connected to one terminal of a first winding of a resonance coil, a choke coil has one terminal connected to one terminal of a second winding of the resonance coil and has the other terminal connected to one terminal of an output capacitor, a rectifier diode has one terminal connected to the connection of the first and second windings and has the other terminal connected to the other terminal of the output capacitor and also to the other terminal of the DC power supply, and a series circuit including an auxiliary switching element and a clamping capacitor is provided between the other terminal of the DC power supply and the connection of the main switching element and the first winding.

Abstract: A DC/DC converter includes a first transformer and a second transformer each having primary windings and secondary windings respectively having first windings and second windings, a second switch connected to both ends of a first series circuit, a fourth switch connected to both ends of a second series circuit, a third series circuit being connected to both ends of the second switch and having the second winding and a second DC power supply, a fourth series circuit being connected to both ends of the fourth switch and having the second winding and the second DC power supply, a reactor connected to both ends of a series circuit having the secondary windings, and a control circuit turning ON/OFF the first and third switches with a phase difference of a half cycle and turning ON/OFF the second and fourth switches with a phase difference of a half cycle.

Abstract: The invention relates to an auxiliary switching circuit (10) for a chopping converter comprising a first inductive element (L0) for serial energy storage with a free-wheel diode (DL) and a switch (K), in addition to a second inductive element (L) for di/dt control when the switch is closed, the auxialiary switching circuit comprising a magnetic circuit (11) whereby a main winding thereof is formed at least partially by the first inductive element (L0), also comprising means (L1, D1, L2, D2) for discharging the second inductive element when the switch is opened or closed, and means (L2, D2) for transferring the energy corresponding to the closure vis a vis said main winding.

Abstract: A constant current regulator that receives an AC input current from a source provides a constant AC current to a load. The regulator includes first, second, third, and fourth electronically controllable switches, a transformer coupled to the switches, and a controller connected to the switches. An output of the first switch is electrically connected to an input of the second switch and one input of the transformer primary winding. An output of the third switch is electrically connected to an input of the fourth switch and another input of the transformer primary winding. The controller provides a trigger signal to each of the switches. The controller adjusts a duty cycle of the trigger signals based on a comparison between an actual current value and a reference current value to provide a constant AC current to the load.

Abstract: An in-line buck/boost voltage/regulating apparatus and system for delivering AC electrical power of regulated voltage from an output terminal of a main winding to an electrical load. The apparatus has an input terminal for connection to an AC power supply and comprises first, second and third ferromagnetic transformer cores having first, second and third cross-sectional areas, respectively; and these cross-sectional areas have relative sizes of X square units, Y square units and Z square units, respectively. There are first, second and third regulator windings respectively mounted on the first, second and third cores, and electromagnetically coupled with their respective cores. The first, second and third windings have first, second and third numbers of turns, respectively. Switching elements selectively connect the first, second and/or third windings across the AC supply and selectively short-circuit any of the first, second and/or third windings which are not connected across the AC supply.

Abstract: A power conversion circuit, in which a flyback converter is modified with additional elements to provide both dissipationless snubbing and also input ripple cancellation. This is achieved by appropriate connection of an additional winding to the isolating transformer, without any need for a second transformer. The configuration of the secondary is conventional, and the switching transistor is connected in series with the primary winding across DC inputs (taken e.g. from a full-wave-rectified line voltage). The additional winding is connected on the primary side, and preferably has a near-unity turns ratio with the primary which is the inverse of the coupling coefficient. However, the additional winding is not connected between the two DC inputs, but instead has one end coupled through an intermediate capacitor to the corresponding end of the primary, and the other end coupled through a capacitor to the negative DC input.

Abstract: Disclosed is a boost converter using a stress energy reproducing snubber circuit, the converter comprising a first inductor connected between one terminal of an input portion and a first connection point; a first diode connected between said first connection point and one terminal of an output portion; and a switching device connected between said first connection point and the other terminal of said input portion, the other terminal of said input portion being connected to the other terminal of said output portion, and further comprising a second inductor connected between said first connection point and an anode of said first diode; a capacitor connected between said first connection point and a second connection point; a second diode having an anode connected to said second connection point and a cathode connected to a cathode of said first diode; and a third inductor and a third diode connected in series between said second connection point and the other terminal of said input portion, said third inductor

Abstract: A dual push-pull induction heating drive circuit comprises an oscillation triggering control circuit regulating the ON-OFF switch of the circuit activation, a switching logic circuit bringing about two exclusive pulse signals serving to drive via an amplifying circuit a dual push-pull switching output circuit having two power elements connected to an induction coil, a pulse width modulating circuit having a controlled comparing element capable of sending out adjustable pulse, and a synchronous detection comparing circuit having at least a comparing element and having an input end in communication with an induction coil and another input end connected with a power source and further having an output end connecting with the switching logic circuit and sending out synchronous pulse signals to a differentiation circuit to bring about synchronous differentiation pulse signals, which are received by the pulse width modulating circuit so as to generate the power control pulse signals serving via the switching logic

Abstract: A voltage regulator particularly adapted to A.C. distributed power systems requiring independent voltage regulation at a plurality of frequency responsive power supply modules energized by a power source at a common alternating frequency is provided by resonant tuning of the regulator circuit. An LC resonant circuit determines the operating frequency of the regulator, and may be operated above or below the excitation frequency. The output voltage is applied to a current amplifier which energizes a linearly variable inductor in accordance with the sensed D.C. output voltage. Changes in the output voltage result in changes in the tuned frequency of the LC circuit and the corresponding corrective change in the output voltage. Circuits providing both voltage and current regulation are described.

Abstract: Power to a load is controlled by actuation of an inductive circuit from a first condition of low inductance to a second condition of higher inductance in response to a preselected overcurrent condition. In a first preferred embodiment, the inductive circuit comprises a pair of coils electrically connectible so that magnetic fields produced by current flow in the coils oppose each other in the first condition, reducing the magnetic flux and thus the effective inductance of the circuit. The magnetic fields are either neutral to each other or reinforce each other in the second condition, giving rise to a higher inductance. Alternatively, the inductive circuit may include one or more fixed value inductors interposed between a power supply and a load in response to an overcurrent condition.

Abstract: A proximity effect heat-tracing system in which proximity effect heat-tracing circuits are fed in either direction from a plurality of feed points connected to a single main transformer to increase the length of pipeline supplied by a single main transformer. A secondary transformer interposed between a main transformer and a plurality of feed points reduces the voltage required to be applied to a proximity effect heat-tracing system of a given length. Two or more proximity effect heat-tracing systems used along the same length of pipeline, employ neutral conductors having approximately the same diameter as "hot" conductors where the secondary of the main transformer in each system is 180.degree. electrically out of phase with the secondary of the main transformer in the other system.

Abstract: An AC-DC welding power supply includes a main transformer in which the primary windings are partially decoupled from the secondary windings to provide a small amount of reactance on the output side of the power supply. A current regulating circuit and a current sensing shunt are mounted between two or more secondary windings for isolation. The current regulating circuit is controlled by a firing control circuit. An adjustable output feedback control circuit, including the shunt and a mixing circuit, provides a mixed current/voltage signal to the firing control circuit according to the current through and voltage across the secondary windings. The power supply output is adjustable from constant voltage through constant current. The output terminals of the secondary windings are connected directly to AC supply terminals and also to DC supply terminals through a rectifier circuit.

Abstract: A parallel resonant induction cooking surface unit comprises a voltage fed inverter which drives a load circuit, comprised of a main induction drive coil, a tuning capacitor coupled in parallel with the main induction drive coil, and an inductor coupled in series with the main induction drive coil, with a square wave voltage, causing the main induction drive coil to generate a time variant magnetic field resulting in eddy currents being induced in the surface of a metallic, food-containing utensil positioned adjacent to the main induction drive coil, and hence, utensil heating. By tuning the load circuit to resonance at or near the square wave frequency, reactive currents therein are minimized, resulting in improved power factor. Moreover, resultant main induction drive coil voltage and current are nearly sinusoidal, thereby achieving reduced electromagnetic interference radiation at frequencies greater than the square wave frequency.

Abstract: A tap changer voltage regulator permits a tap changer selector contact to engage an open circuited new tap without arcing and has a half-tap voltage auxiliary winding which permits halving the inter-tap voltage to thus double the number of steps, and an auxiliary switch with a pair of movable contacts. A first auxiliary contact initially connects a selector contact which has moved to a new tap through a circulating current limiting resistor to a load, preventing load current interruption. A second auxiliary contact is in series with a normally-closed switch through which load current and circulating current flow. A first set of inverse parallel SCR's is in series with the resistor, while the normally-closed switch is shunted by a second pair of inverse parallel thyristors. The first pair of thyristors is not gated until the first auxiliary contact has attained its new position, precluding initial arcing.