A system for extracting energy from an energy storage device configured to supply direct current (DC) energy at a nominal voltage rating comprises a first node dimensioned and arranged to receive direct current energy from the energy storage device. Embodiments include a self-oscillating circuit having primary and secondary windings wound around a ferrite core, wherein a positive terminal of the primary winding is tied to the negative terminal of the secondary winding at the first node, and wherein a positive terminal of the secondary winding is coupled to a second node, the second node being coupled to a load requiring power to be supplied at one of a voltage less than, equal to, or higher than the nominal voltage. Some embodiments further include a transistor having a base resistively coupled to a negative terminal of the primary winding and a collector coupled to the second node.

A thermal increase system includes a cavity, a first electrode disposed in the cavity, a second electrode disposed in the cavity, and a self-oscillator circuit that produces a radio frequency signal that is converted into electromagnetic energy that is radiated into the cavity by the first and second electrodes. The self-oscillating circuit includes the first electrode and the second electrode. In an embodiment, the first electrode is a first plate in a capacitor structure and the second electrode is a second plate in the capacitor structure. The cavity and a load contained within the cavity operates as a capacitor dielectric of the capacitor structure. A resonant frequency of the self-oscillator circuit is at least partially determined by a capacitance value of the capacitor structure.

A thermal increase system includes a cavity, a first electrode disposed in the cavity, a second electrode disposed in the cavity, and a self-oscillator circuit that produces a radio frequency signal that is converted into electromagnetic energy that is radiated into the cavity by the first and second electrodes. The self-oscillating circuit includes the first electrode and the second electrode. In an embodiment, the first electrode is a first plate in a capacitor structure and the second electrode is a second plate in the capacitor structure. The cavity and a load contained within the cavity operates as a capacitor dielectric of the capacitor structure. A resonant frequency of the self-oscillator circuit is at least partially determined by a capacitance value of the capacitor structure.

A control board of a power conversion device, the control board includes a board main body, a plurality of drive circuits, a power source control circuit, an insulation region, a plurality of insulation transformers, and a connecting line that electrically connects the plurality of insulation transformers and the power source control circuit to each other, and at least a part of which extends in a region in inner layers of the board main body that overlaps the insulation region when viewed in a perpendicular direction with respect to the surface of the board main body.

A converter includes a DC input; a transformer including first and second primary windings, first and second secondary windings, and first and second feedback windings; a first field-effect transistor; a second field-effect transistor; and a drive circuit connected to the first and second field-effect transistors. The drive circuit includes a bias circuit that applies a bias voltage to gates of the first and second field-effect transistors via the first and second feedback windings during start-up of the converter, wherein the bias voltage is reduced to zero or substantially zero after start-up of the converter; and a reset circuit that resets the bias circuit when the converter is turned off. The converter is a self-oscillating push-pull DC-DC converter.

An output stabilization circuit includes: a primary-side circuit including first and second self-excited oscillator circuits connected to a direct-current power supply; and a secondary-side circuit, wherein the first and second self-excited oscillator circuits include power transmission coils, resonant capacitors, switching element pairs, and feedback coils, the second self-excited oscillator circuit further includes a phase shift filter, the phase shift filter includes a primary-side control coil that is magnetically coupled to a secondary-side control coil included in the secondary-side circuit and that has a characteristic that an inductance changes depending on a current flowing through the secondary-side control coil.

In accordance with an embodiment, an oscillator circuit includes: a main current path coupled between a supply voltage terminal and a ground terminal, the main current path including a parallel resonant circuit, a load current path of a first transistor and a load current path of a second transistor. The parallel resonant circuit includes an inductor formed by a primary winding of a transformer, and a first capacitor; a terminal of the inductor is connected to the ground terminal; the load current path of the first transistor is coupled between the parallel resonant circuit and the load current path of the second transistor; and the parallel resonant circuit is coupled to a control electrode of the second transistor via a feedback path that includes a second capacitor.

A method and an apparatus for transferring electric power to an electrical load (105); the method includes steps of: converting a direct electric current into an electric tension wave, applying the electric tension wave in inlet to at least a couple of electric capacitors (125, 130); supplying the electrical load (105) with the electric tension in outlet from the capacitors (125, 130).

A contactless communication medium, includes: a coil sensitive to a magnetic field; a rectifying circuit configured to rectify an alternating power energy generated in the coil; a smoothing circuit configured to smooth a rectified output outputted from the rectifying circuit to generate a DC voltage; an output terminal connected to the smoothing circuit; a voltage detecting circuit configured to compare an output voltage extracted from the output terminal with a reference voltage; a switch configured to operate in response to an output from the voltage detection circuit and to attenuate the alternating power energy generated in the coil when the output voltage reaches a predetermined value; and a load connected to the output terminal, wherein impedance of the load has a value such that the output voltage has a predetermined value when an effective value of the magnetic field applied to the coil is 12 A/m or more.

Provided is a high-frequency power supply device capable of causing an appropriate current to flow through a transformer. A self-oscillation high-frequency power supply device is provided with a DC power supply, an LC resonant circuit, a switching circuit, and a transformer. The LC resonant circuit includes an induction coil for plasma generation and a capacitor. The switching circuit includes a semiconductor element, the switching circuit being configured to subject DC power supplied from the DC power supply to switching processing to supply high-frequency power to the LC resonant circuit. The transformer includes a primary coil included in the LC resonant circuit and a secondary coil connected to the semiconductor element to turn on/off a semiconductor element. The transformer has a coaxial structure in which the primary coil and the secondary coil are coaxially provided. The LC resonant circuit includes a resistor connected in parallel to the primary coil.