Abstract: The present disclosure provides a starter circuit for energy harvesting circuits for an energy source having a first and a second potential of an input voltage, in particular for thermoelectric generators.

Abstract: In described examples, an isolated DC-DC converter includes: an input node for receiving an input voltage; a transformer including a primary side having first and second terminals and a primary side ground; and first and second low-side switches. The first low-side switch is coupled between the first terminal and the primary side ground. The second low-side switch is coupled between the second terminal and the primary side ground. A first voltage is across the first low-side switch, and a second voltage is across the second low-side switch. Also, the isolated DC-DC converter includes first and second high-side switches. The first high-side switch is coupled between the first terminal and the input node. The second high-side switch is coupled between the second terminal and the input node. Further, the isolated DC-DC converter includes a switch controller.

Abstract: When a resonant frequency of a power transmission-side resonance mechanism is expressed by fra, a switching frequency of a first switch circuit and a second switch circuit is expressed by fs, and a resonant frequency of the power transmission-side resonance mechanism and a capacitor of the first switch circuit or the second switch circuit is expressed by frb, a relation of fra<fs?frb is satisfied.

Abstract: A magnetic resonance wireless power transmission device capable of adjusting resonance frequency is disclosed. A wireless power transmission device according to an embodiment of the present invention comprises: a power amplifier for amplifying a wireless power signal using a driving frequency signal; a resonator for configuring a resonance tank and wirelessly transmitting, through magnetic resonance, the wireless power signal output from the power amplifier using a resonance frequency of the resonance tank; and a resonance control unit for controlling a duty ratio using a frequency applied to the resonator or a frequency signal generated by the resonator and adjusting the resonance frequency of the resonator.

Abstract: Disclosed is a resonance type power transmission device that transmits electric power by using a resonator for transmission 3 and a resonator for reception 4 whose resonance conditions are matched to each other, the resonance type power transmission device including a transmission power supply 1 to supply electric power, a transmission antenna 2 to transmit the electric power from the transmission power supply 1, a conductive substance 7 to establish an electrical single point connection between the resonator for transmission 3 and the resonator for reception 4, a reception antenna 5 to receive the electric power from the transmission antenna 2 via the resonator for transmission 3 and the resonator for reception 4, and a reception power supply 6 to receive the electric power received by the reception antenna 5.

Abstract: An apparatus controls a DC-DC converter that converts an input voltage to an output voltage. The DC-DC converter includes a switching element having a duty ratio controlled by the apparatus to regulate the output voltage, a first transformer, a second transformer and a capacitor. A terminal voltage applied between input and output terminals of the switching element varies depending on the duty ratio and the input voltage. The apparatus may be configured to: limit the duty ratio in response to the input voltage represented by a modulated signal; enable the DC-DC converter to continue to convert the input voltage to the output voltage when an abnormal condition of the modulated signal is determined; and limit the duty ratio of the switching element when the abnormal condition is determined. Main and sub switching elements of the switching element and the capacitor are disposed between the first and second transformers.

Abstract: A power supply system for supplying electrical power to a load is capable of delivering an output voltage to the load from an input voltage coming from an electric power network. The power supply system includes: at least two input terminals and at least two output terminals, the input terminals being adapted to be connected to the electric power network and the output terminals being adapted to be connected to the load, a converter capable of converting the input voltage into the output voltage, the converter being connected between the input terminals and the output terminals, and a device for limiting the homopolar current that is likely to flow between the electric power network and the load. The device for limiting the homopolar current comprises a transformer connected in parallel with respect to the converter, between the input terminals and the output terminals, the transformer having a first electromagnetic coil and a second electromagnetic coil.

Abstract: An electrical powered vehicle includes a secondary self-resonant coil, a secondary coil, a rectifier, and a power storage device. The secondary self-resonant coil is configured to be magnetically coupled with a primary self-resonant coil of a power feeding device by magnetic field resonance, and allow reception of high frequency power from the primary self-resonant coil. The secondary coil is configured to allow reception of electric power from the secondary self-resonant coil by electromagnetic induction. The rectifier rectifies the electric power received by the secondary coil. The power storage device stores the electric power rectified by the rectifier.

Abstract: A first rectified voltage obtained by rectifying an AC voltage is input to an input detection terminal of a control circuit. A first NMOS transistor configured as a depletion-type high-voltage element, and its drain is connected to the input detection terminal, and its gate is connected to its source. An AC voltage detection circuit detects the amplitude of the AC voltage based on a current that flows through the first NMOS transistor.

Abstract: An induction heating system includes an induction heating coil operable to inductively heat a load with a magnetic field, a detector for detecting a current feedback signal corresponding to a current flowing through the induction heating coil, and a controller for detecting a switching transient in the current feedback signal and determining a resonant frequency of the system based on a characteristic of the switching transient.

Abstract: A dimmable LED driver adapted to be operated with a dimmer that is configured to generate a predetermined conductive angle, wherein the dimmable LED driver comprises: a rectifier configured to convert an alternating current output by the dimmer to a direct current, a buck PFC block configured to adjust an output voltage of the direct current so as to obtain a stable output voltage, a second buck DC/DC block configured to realize output of a constant current after the stable output voltage is realized, a dimming block configured to, after realizing output of the constant current, accomplish a dimming function jointly with the second buck DC/DC block, and an MCU configured to control the buck PFC block, the second buck DC/DC block and the dimming block.

Abstract: The present invention provides an LED backlight drive circuit, which includes a first power supply module, an electrical inductor, a rectifier diode, a MOS transistor, an electrolytic capacitor, an LED light string, a voltage division module, a voltage comparator, a second power supply module, and an LED constant-current drive chip. The LED backlight drive circuit is arranged to include a voltage comparator in an external circuit of the LED constant-current drive chip to detect output voltage of the drive circuit so that high voltage, the voltage comparator is caused to supply a low voltage level to forcibly pull down a PWM dimming signal or an ENA enabling signal of the LED constant-current drive chip to achieve an over-voltage protection function and also enable removal of over-voltage protection module from a conventional LED constant-current drive chip.

Abstract: A switching power source apparatus has a pulse generator of a first pulse. A first resonant series circuit receives the first pulse signal and passes a current having a 90-degree phase delay with respect to the first pulse signal. The current of the first resonant series circuit turns on/off a switching element Q21. A second resonant series circuit receives the second pulse signal and passes a current having a 90-degree phase delay with respect to the second pulse signal. The current of the second resonant series circuit turns on/off a switching element Q22. The pulse generator has a third transformer T3 that has secondary windings to output the first and second pulse signals according to a voltage that is applied to the third transformer and is synchronized with drive signals for the switching elements Q11 and Q12.

Abstract: A switching power supply apparatus includes a low-side switching control unit and a high-side switching control unit. The low-side switching control unit includes a low-side turn-off circuit that turns off a low-side switching element behind a delay time when reversal of the polarity of a winding voltage of a transformer is detected during a period in which a drive voltage signal is supplied to the low-side switching element. The high-side switching control unit includes a high-side turn-on delay circuit that delays a time from the time when the polarity of the winding voltage of the transformer is reversed to a time when a high-side switching element is turned on. The delay time of the low-side turn-off delay circuit is set so as to be shorter than the delay time of the high-side turn-on delay circuit.

Abstract: A switching control IC conducts on-off control on a first switching element. A second switching control circuit is provided between a high-side driving winding of a transformer T and a second switching element. The second switching control circuit discharges a capacitor in a negative direction with a constant current during an on period of the first switching element, and then after the second switching element is turned on, charges the capacitor in a positive direction with a constant current. A transistor controls the on period of the second switching element in accordance with the ratio of a charging current to a discharge current such that the ratio of the on period of the second switching element to the on period of the first switching element is substantially always constant.

Abstract: In an induction motor group control system, magnetic energy recovery switches (3) are connected in series to an induction motor (2) directly driven by a commercial power supply, and a plurality of induction motor control devices (10) enabling voltage control and reactive power control of the induction motor 2 are employed to control generation of reactive power so as to maximize a power factor of the entire plurality of AC loads including the induction motor or compensate variations in voltage of an AC power supply (1).

Abstract: A drive system has a low voltage system, a high voltage system, and a transformer. The high voltage system has drive units which correspond to power switching elements. A capacitance in the high voltage system serves as a flouting power source which supplies electric power to each of the drive units. An output voltage of a secondary side coil of the transformer is supplied to the capacitance. A comparator compares the output voltage at the secondary side coil of the transformer with a threshold value. A switching speed change part changes the switching speed of each of the power switching element based on the comparison result of the comparator.

Abstract: Provided is a transformer, comprising a first winding and a second winding that interlink with a main magnetic flux; and a third winding that interlinks with a magnetic flux leakage interlinking with only one of the first winding and the second winding.

Abstract: A circuit for an oscillator structured to drive a control device of a switching resonant converter; the converter having a switching circuit structured to drive a resonant load provided with at least one transformer with at least a primary winding and at least a secondary winding. The control device structured to drive the switching circuit, and the converter structured to convert an input signal into an output signal, the integrated circuit includes a first circuit structured to charge and discharge a capacitor by a first current signal such that the voltage at the ends of the capacitor is between first and second reference voltages, the current signal having a second current signal indicating the output voltage of the converter; the integrated circuit including a second circuit structured to rectify a signal indicating the current circulating in the primary winding.

Abstract: A DC-to-DC converter includes a high-side transistor and a low-side transistor wherein the high-side transistor is implemented with a high-side enhancement mode MOSFET. The low side-transistor further includes a low-side enhancement MOSFET shunted with a depletion mode transistor having a gate shorted to a source of the low-side enhancement mode MOSFET. A current transmitting in the DC-to-DC converter within a time-period between T2 and T3 passes through a channel region of the depletion mode MOSFET instead of a built-in diode D2 of the low-side MOSFET transistor. The depletion mode MOSFET further includes trench gates surrounded by body regions with channel regions immediately adjacent to vertical sidewalls of the trench gates wherein the channel regions formed as depletion mode channel regions by dopant ions having electrical conductivity type opposite from a conductivity type of the body regions.

Abstract: Systems and methods for a dual illumination watch face having a tritium gas tube coupled with a dial, minute hand or hour hand of the watch face, and phosphorescent material disposed with at least one of the dial, minute hand and hour hand.

Abstract: A control device for controlling a recovery from a locking of a motor includes: a switching unit which supplies a motor current from a current supplying unit to the motor; and a driving control unit which supplies a PWM control signal to the switching unit to control a driving of the switching unit. The driving control unit supplies the PWM control signal with a low duty ratio lower than a regular duty ratio to the switching unit when the locking of the motor is detected depending on a variation in temperature of the switching unit. The driving control unit supplies the PWM control signal with the regular duty ratio to the switching unit when a cancel of the locking of the motor is detected depending on a variation in inter-terminal voltage of the motor.

Abstract: A light emitting diode (LED) lighting system includes a PFC and output voltage controller and a LED lighting power system. The controller advantageously operates from an auxiliary voltage less than a link voltage generated by the LED lighting power system. The common reference voltage allows all the components of lighting system to work together. A power factor correction switch and an LED drive current switch are coupled to the common reference node and have control node-to-common node, absolute voltage that allows the controller to control the conductivity of the switches. The LED lighting system can utilize feed forward control to concurrently modify power demand by the LED lighting power system and power demand of one or more LEDs. The LED lighting system can utilize a common current sense device to provide a common feedback signal to the controller representing current in at least two of the LEDs.

Abstract: At least some aspects of the invention are directed to methods and apparatus for controlling an uninterruptible power supply and subsystems of a UPS. A first aspect of the invention is directed to a method of controlling a DC-DC converter having a predetermined maximum peak load current value. The DC-DC converter has first and second outputs to couple to a load with a capacitor coupled across the first and second outputs. The method includes in a first mode of operation, charging the capacitor to a predetermined output voltage value, and in a second mode of operation, providing output current having the maximum peak load current value to a load coupled to the output of the DC-DC converter, wherein a first portion of the output current is provided by the DC-DC converter and a second portion of the output current is provided by discharging the capacitor to a voltage value that is less than the predetermined output voltage value.

Abstract: A vehicle (100) includes a motor generator (MG) and an inverter (14) driving the motor generator (MG). A power source apparatus for the vehicle includes a battery (B) as an electric storage device, a step-up converter (12) stepping up a voltage of the electric storage device and supplying it to the inverter, and a controller (30) indicating a target step-up voltage in accordance with a target state of operation of the motor generator (MG) to the step-up converter (12). If it is determined that a current operation state signal of the motor generator (MG) is abnormal, the controller (30) increases the target step-up voltage to a maximum value. Preferably, the vehicle (100) further includes a resolver (20) detecting rotation speed of a rotor of motor generator (MG). The controller (30) determines that the operation state signal is abnormal if an output of the resolver (20) does not satisfy a prescribed condition.

Abstract: The present invention is intended to prevent the flow of a large input current into a DC/DC converter, to which power is fed from a power supply, before a supply voltage delivered from the power supply reaches a rated output voltage. A control unit included in the DC/DC converter includes a steady state detection block that detects a condition in which an input voltage to be applied to the DC/DC converter has been stabilized, and inhibits the power feed from the DC/DC converter until the input voltage delivered from a power supply in a preceding stage is stabilized.

Abstract: A half-bridge resonant converter includes: a primary winding; a secondary winding having a first and a second end and a central point; a first electronic switch; a second electronic switch; a first power-storage element; a second power-storage element; and a load having a first and a second end. Wherein, the first end of said the secondary winding serially connects with said the first electronic switch and the first power-storage element, and the second end of said the secondary winding serially connects with said the second electronic switch and the second power-storage element, and the first end of said the load connects simultaneously with said the first power-storage element and the second power-storage element, and the second end connects with the central point of the secondary winding.

Abstract: The present invention discloses a secondary side-driven half-bridge power supply, which has a half-bridge transformer. A MOSFET unit is connected to the primary side of the half-bridge transformer, and an output rectifier/filter circuit connected to the secondary side of the half-bridge transformer. In the present invention, a PWM controller generates a control signal and sends the signal to a separating element. The control signal is used to drive the MOSFET unit, and the MOSFET unit then drives the half-bridge transformer. The output rectifier/filter circuit processes the signal output by the half-bridge transformer to provide voltages for external loads. The present invention can increase the power efficiency, raise the working frequency, and reduce the cost.

Abstract: A system and method are described for controlling voltage on discharge capacitors which control light energy from flash lamps, wherein the method includes measuring over time an operational behavior of a flash lamp for performing photothermolysis, wherein a discharge capacitor transfers energy to the flash lamp, empirically deriving a behavior of the flash lamp as a function of operation over time, and using the empirically derived behavior of the flash lamp to control a voltage of the discharge capacitor and thus energy transferred to the flash lamp.

Abstract: A protection device protects a driving device of an electric motor with at least three phases and at least three windings and the driving device comprises a power stage suitable for driving directly said at least three windings. The driving device is suitable for actuating a motor brake operating phase and comprises detectors suitable for detecting the currents that run in the windings of the motor. The protection device comprises selectors suitable for selecting the currents having a single direction between said detected currents and a deactuator suitable for deactuating the power stage during said motor brake operating phase when the sum of the currents having a single direction is greater than a reference current.

Abstract: A resonant switching power system operates with two resonant frequencies. A first frequency depends on the secondary leakage inductance of an output transformer and capacitor. The first frequency varies with changes in the load because load changes alter the leakage inductance. A second resonant frequency depends on the gate source capacitance of two MOSFET power devices in the circuit and the leakage inductance of the circuit's driving transformer. Power is thereby supplied that is always in phase with the load so that switching in the power supply occurs when current is near zero. High thermal efficiency is thereby achieved.

Abstract: A bidirectional active power conditioner includes a DC side, a bidirectional DC/DC power converter, a DC/AC inverter and an AC side. The DC side electrically connects with a DC source while the AC side electrically connects with a load and an AC source. The bidirectional DC/DC power converter is controlled via high-frequency pulse width modulation (PWM) switching so as to generate a predetermined DC voltage or DC current while the DC/AC inverter is controlled to convert the predetermined DC voltage or DC current into a predetermined AC voltage or AC current.

Abstract: A step-up converter based on an integrated transformer, comprising a self-resonating oscillator circuit that has inductive elements constituted by primary and secondary windings of at least one first transformer, the self-resonating oscillator circuit being powered by an external supply voltage.

Abstract: The invention discloses a half-bridge LLC resonant converter with a synchronous rectification function that includes a first switch; a second switch; a first transformer; a first synchronous rectifier; a second synchronous rectifier; a controller; and a second transformer. The controller of the half-bridge LLC resonant converter with a synchronous rectification function can control the first synchronous rectifier and the second synchronous rectifier directly and the connected second transformer also can control the first switch and the second switch directly. The first synchronous rectifier and second synchronous rectifier having a low conducting resistance substitute the rectifier and greatly lower the power consumption. The controller outputs a control signal to drive a transformer to output a signal to the primary winding, and its signal delay is formed by a delay of an electronic circuit and a power MOS switch of the first switch and second switch.

Abstract: A drive transformer and associated circuitry for providing power and appropriate delays to primary switches and synchronous rectifiers in switch-mode power converters. The circuitry takes advantage of the leakage inductances of the drive transformer windings as well as the input capacitance of the primary switches (MOSFETs) to provide the necessary delays. No separate circuitry is needed to provide such delays, thereby providing reliability. Exemplary embodiments further disclose means to disable or enable the primary winding from a condition sensed on the secondary side even with a control and feedback circuit located on the secondary side.

Abstract: A lighting circuit for lighting a vehicular lamp including a plurality of light-emitting diodes, includes: a selection unit for selecting the number of light-emitting diodes to be connected in series in the vehicular lamp based on an instruction from the outside; a switching regulator for applying an output voltage based on a power-supply voltage output by an external DC power supply to the selected number of light-emitting diodes to be connected in series, so as to supply a supply current to the selected number of light-emitting diodes; and an output controlling unit for controlling the output voltage of the switching regulator based on the supply current.

Abstract: There is provided a type of luminous hand including a part made of moulded transparent material that forms a circular head (28, 35) and a body (28, 34) of a hand. In order to direct a portion of a light beam parallel to the axis (15) of the hand towards the interior of the body, the head includes a plurality of reflectors (40, 41) distributed around the axis and formed by dihedron shaped hollows. This improves the intensity and uniformity of the light in the hand body. Inclined light-diffusing surfaces, covered with a light coloured paint, are arranged on the bottom face of the hand. In a display device with several coaxial hands (11,12) such as that of a watch, the reflectors of the superposed heads (29, 35) of the hands are located at respective distances from the axis which are different from one hand to another, such that they never completely cover each other. The light source preferably includes three light-emitting diodes (23) located under the dial (10).

Abstract: An AC/DC switching power supply that realizes a high power factor and has little voltage stress on a smoothing capacitor is provided. Also a switching power supply that has little voltage stress on a switch and is suitable for reduction in loss and miniaturization is provided.

Abstract: A backlight inverter for an LCD panel which is capable of detecting a fault in a transformer device including two transformers driven in tandem or an open-lamp condition and performing a control operation to stop its operation upon detecting the fault in the transformer device or the open-lamp condition. The inverter supplies a PWM signal through a switch in normal operation. The inverter also detects a voltage corresponding to current flowing through each lamp in a lamp device and determines from the detected voltage whether the open-lamp condition has occurred. The inverter further detects a voltage at a midpoint of secondary windings of the transformer pair in the transformer device and determines from the detected voltage whether the fault exists in the transformer device. In the event of the open-lamp condition or the fault in the transformer device, the inverter turns off the switch.

Abstract: A battery voltage is increased in a converter and is input to an inverter that supplies a motor with a motor drive current. A control unit detects input and output voltages of the converter from outputs of voltage sensors and controls the switching in the converter in accordance with the detected input and output voltages. When one of the sensors fails, the control unit estimates the voltage that would have otherwise been detected by the failed voltage sensor based on the switching state in the converter and the voltage detected by the other voltage sensor.

Abstract: A switching power supply includes a transformer having a primary winding connected to a pair of a.c. input terminals via a rectifier circuit, and a secondary winding connected to a pair of d.c. output terminals via a rectifying and smoothing circuit. Connected between the pair of outputs of the rectifier circuit via an inductor, reverse-blocking diode, and part or whole of the transformer primary, a primary switch is turned on and off at a repetition frequency higher than the frequency of the a.c. input voltage. A soft-switching circuit is provided which comprises a serial connection of a transformer tertiary, an ancillary diode and an ancillary switch. This serial circuit is connected in parallel with the serial connection of the transformer primary and primary switch for zero-voltage switching of the primary switch.

Abstract: An electronic stabilizer includes an output transformer, a variable frequency/power amplifying loop, a low voltage variable frequency rectifying loop, and two elements of high resistance value. The primary side of the output transformer is connected with the variable frequency/power amplifying loop. The secondary side of the output transformer is connected with the low voltage variable frequency rectifying loop and the voltage boosting and lamp lighting loop. The elements of high resistance value are connected with the nodes of the various frequency/power amplifying loop and the low voltage variable frequency rectifying loop. The electronic stabilizer is adapted to an environment of direct current low voltage or direct current high voltage in which a low voltage bias current is provided to drive a lamp.

Abstract: A push-pull inverter is supplied from an inductively current-limited DC voltage source by way of a center-tap on a transformer having significant inductance. This transformer inductance is parallel-coupled with a capacitance means. The inverter is made to self-oscillate through positive feedback provided by way of a saturable current transformer. The inverter frequency is determined by the saturation time of this current transformer, which saturation time is designed to be somewhat longer than the half-cycle period of the natural resonance frequency of the transformer inductance combined with the capacitance means. By controlling the length of this saturation time, the magnitude of the current provided to the fluorescent lamp is controlled, thereby permitting control of the light output in response to changes in the magnitude of the power line voltage.

Abstract: A white light-emitting-diode array driver circuit with a multiple output flyback (or forward) converter with output current mode control. The circuit comprises a power supply source and a transformer. The transformer has a primary winding coupled to, and configured to receive current from, the power supply, and a plurality of secondary windings coupled to the primary winding. The circuit also comprises a plurality of light-emitting-diode arrays, wherein each light-emitting-diode array is coupled to one of the secondary windings. A main controller is coupled to a first of the light-emitting-diode arrays and is configured to control a flow of current to the primary transformer winding. The circuit also comprises a plurality of secondary controllers, each of which are coupled to another of the light-emitting-diode arrays. In addition, each of the secondary controllers are configured to control a flow of current to its corresponding light-emitting-diode array.

Abstract: The invention relates to a circuit arrangement for operating a semiconductor light source, comprising input terminals for connecting a supply voltage, input filter means, a converter provided with a switching element having a control circuit, and provided with inductive means, and output terminals for connecting the semiconductor light source. The switching element is periodically driven into conduction for a period ton. According to the invention, the converter is formed by a flyback converter, and the inductive means are formed by a transformer, and the control circuit controls the ton.

Abstract: A synchronous rectification circuit for a DC-DC power converter can operate efficiently with a primary drive voltage that remains at a zero voltage level during a portion of the power conduction cycle. The DC-DC power converter includes a primary side power circuit providing a symmetrically varying power signal that remains at a zero voltage level for a portion of a conduction cycle. A first secondary side power circuit is inductively coupled to the primary side power circuit, and has an output terminal that provides an output voltage. The first secondary side power circuit further comprises first and second synchronous rectifiers having respective activation terminals. The synchronous rectifiers are adapted to alternately activate in synchronism with non-zero voltage level portions of the conduction cycle. A second secondary side power circuit is inductively coupled to the first secondary side power circuit and has polarity reversed with respect to the first secondary side power circuit.

Abstract: Inductive power transfer across an extended gap (100) from a primary conductor (119) is provided by means of a resonant intermediate loop comprised of capacitor (118) with inductor (117) carrying a larger resonating current, that can in turn generate an inductive field to be collected by a pickup coil (120). This process and device find application in an electroluminescent advertising panel.

Abstract: A self oscillating power converter uses two MOSFET transistors connected across first and second primary windings. Each MOSFET is controlled using a gate control circuit located in a feedback path. Each gate control circuit is driven by a gate drive winding which is transformer coupled to a primary winding and which is phased with the primary winding such that regenerative feedback causes accelerated sequential turn-on and turn-off of the associated MOSFET transistor. Each feedback path includes a capacitor for charging in response to the voltage generated across the gate drive winding to initiate turn-on of the MOSFET transistor and a resistor for discharging the capacitor to initiate turn-off of the MOSFET transistor. The power converter can be configured as a push-pull converter in either a common-drain or common-source configuration. The power converter can also be configured such that at least one MOSFET transistor is capacitively coupled to a primary winding.

Abstract: A self-oscillation-resonance type power supply circuit having a stabilizer for output voltages or output currents. A transformer and two transistors (a first transistor and a second transistor) are used to form a push-pull type self-oscillation-resonance type power supply circuit. Feedback signals that change according to resonant voltages are inputted to individual gates of the first transistor and the second transistor, a controller for generating error signals corresponding to the difference between a voltage signal and a reference signal is included in the circuit, and the error signals are fed to the individual gates of the first transistor and the second transistor, whereby conduction timing of the individual transistors is changed to vary the self-oscillation frequency.

Abstract: An inductively coupled power distribution system for moving vehicles, in which resonating primary circuits to distribute power for resonating secondary circuits to collect and use in an optimized manner. In order to have all circuits resonating at substantially the same frequency, devices which detect and adjust resonating components are used, such as a frequency drift compensator in which the present frequency is compared to a reference voltage and causes a driver to be ON or OFF accordingly. Switches are driven CLOSED or OPEN respectively and when CLOSED, supplementary capacitors are included with a main capacitor in a primary resonant circuit. Dithering or pulsed control provides a continuous control of resonance, as the system takes some milliseconds to respond.