A variable capacitor includes an enclosure having first and second conductive collars separated by an intermediate electrically insulating element. A movable capacitor plate assembly is electrically coupled to the first conductive collar, and a fixed capacitor plate assembly is electrically coupled to the second conductive collar. An actuator extends into the enclosure for advancing and retracting the movable capacitor plate assembly relative to the fixed capacitor plate assembly. A hermetically sealed volume within the enclosure contains a dielectric fluid serving as a dielectric between a capacitor plate of the movable capacitor plate assembly and a capacitor plate of the fixed capacitor plate assembly. A flexible structure is provided to contain the dielectric fluid displaced when the movable capacitor plate assembly is advanced toward the fixed capacitor plate assembly.

A variable capacitor includes an enclosure having first and second conductive collars separated by an intermediate electrically insulating element. A movable capacitor plate assembly is electrically coupled to the first conductive collar, and a fixed capacitor plate assembly is electrically coupled to the second conductive collar. An actuator extends into the enclosure for advancing and retracting the movable capacitor plate assembly relative to the fixed capacitor plate assembly. A hermetically sealed volume within the enclosure contains a dielectric fluid serving as a dielectric between a capacitor plate of the movable capacitor plate assembly and a capacitor plate of the fixed capacitor plate assembly. A flexible structure is provided to contain the dielectric fluid displaced when the movable capacitor plate assembly is advanced toward the fixed capacitor plate assembly.

A variable capacitor includes an enclosure having first and second conductive collars separated by an intermediate electrically insulating element. A movable capacitor plate assembly is electrically coupled to the first conductive collar, and a fixed capacitor plate assembly is electrically coupled to the second conductive collar. An actuator extends into the enclosure for advancing and retracting the movable capacitor plate assembly relative to the fixed capacitor plate assembly. A hermetically sealed volume within the enclosure maintains a vacuum or a liquid serving as a dielectric between a capacitor plate of the movable capacitor plate assembly and a capacitor plate of the fixed capacitor plate assembly. At least one capacitor plate comprises a coiled cylindrical plate having a having a greater height at a center portion of the capacitor plate coil and a lower height at an outer portion of the capacitor plate coil.

A low radio frequency electro-mechanical load pull impedance tuner uses four rotary, remotely controlled variable shunt capacitors and three fixed series transmission lines to create up to 10.sup.8 independently controllable impedance states at each frequency covering the entire Smith chart in the frequency range between 1 and 10 MHz; the capacitors and control motors and gear are immersed in high epsilon dielectric fluid inside individual sealed containers. Appropriate Error Function-based optimization algorithms, allow fast impedance tuning at the fundamental frequency at the output of DUT's operated in high gain compression. Stepper motors, drivers and control software are used to remotely control the variable shunt capacitors of the tuner and allow it to be automated, pre-calibrated and used in an automated load pull measuring setup.

Provided are a flexible variable capacitor and method for preparation thereof. The flexible variable capacitor includes two highly conductive flexible electrode layers and an elastomer dielectric insulation layer disposed between the two highly conductive flexible electrode layers, wherein the highly conductive flexible electrode layers include first polymeric elastomer and carbon nanomaterial, and the elastomer dielectric insulation layer includes second polymeric elastomer and functional ceramic nanoparticles. The method for preparation of the flexible variable capacitor is as follows: first, preparing an elastomer composite film with different functions, and then pressing upper and lower electrode layers with the intermediate elastomer insulation layer together to obtain a stretchable strip-shaped plate capacitor. Different from existing technologies, the present application uses independently developed highly conductive flexible electrodes to replace traditional silver oil electrodes, which greatly reduces the cost of variable capacitor devices, and enhances the integration and operability. The prepared flexible variable capacitor has characteristics such as high dielectric constant, low dielectric loss, simple preparation process, and capacitance being sensitive to deformation.

A variable capacitor is disclosed. The variable capacitor includes a multi-layer ceramic capacitor member, and a capacitance varying mechanism. The multi-layer ceramic capacitor member includes one or two external electrode(s), a ceramic dielectric, and a plurality of electrode layers positioned inside the ceramic dielectric. The capacitance varying mechanism includes an electrical conductor positioned aside and approximate to the ceramic dielectric. The electrical conductor is deformable responsive to a pressure applied thereon, and an area of the electrical conductor in contact with the ceramic dielectric varies in accordance with the pressure, thus varying a capacitance value between the external electrode(s) and the electrical conductor. In general, the external electrode(s) of the multi-layer ceramic capacitor member serve(s) as fixed electrode(s) of the variable capacitor.

A variable capacitor is disclosed. The variable capacitor includes a multi-layer ceramic capacitor member, and a capacitance varying mechanism. The multi-layer ceramic capacitor member includes one or two external electrode(s), a ceramic dielectric, and a plurality of electrode layers positioned inside the ceramic dielectric. The capacitance varying mechanism includes an electrical conductor positioned aside and approximate to the ceramic dielectric. The electrical conductor is deformable responsive to a pressure applied thereon, and an area of the electrical conductor in contact with the ceramic dielectric varies in accordance with the pressure, thus varying a capacitance value between the external electrode(s) and the electrical conductor. In general, the external electrode(s) of the multi-layer ceramic capacitor member serve(s) as fixed electrode(s) of the variable capacitor.

A generator comprises a parallel plate capacitor which in turn is made up of a mobile plate and a stationary plate, the plates facing each other in parallel at their internal faces. The mobile plate moves up and down due to an external mechanical force to increase and decrease the gap between the plates, leading to a change in the capacitance between the mobile plate and the stationary plate. The internal faces of the plates have dielectric surfaces, for example formed by oxidizing. The generator is useful for example for small-scale mobile devices such as wearables, and to any device where motion is available to transform into electricity.

A capacitive element using a liquid as a dielectric, whereby the capacitance is prevented from changing. The capacitive element is equipped with: a storage container that has an inlet port for introducing a liquid serving as a dielectric, has an outlet port for discharging the liquid, and is filled with the liquid; and at least one pair of electrodes that are provided in the storage container and face each other, wherein an opening section for exhausting air bubbles in the storage container is formed in an upper wall of the storage container.

A capacitive element using a liquid as a dielectric, whereby the capacitance is prevented from changing. The capacitive element is equipped with: a storage container that has an inlet port for introducing a liquid serving as a dielectric, has an outlet port for discharging the liquid, and is filled with the liquid; and at least one pair of electrodes that are provided in the storage container and face each other, wherein an opening section for exhausting air bubbles in the storage container is formed in an upper wall of the storage container.