Disclosed is a device for filtering electrical noise in a vehicle. The device includes a housing connectable to the vehicle, a variable capacitor, an input signal line coupled to the variable capacitor and couplable to a first conductor that carries electrical signals along with electrical noise of a given amplitude, and an output signal line coupled to the variable capacitor and couplable to a second conductor. When the input signal line is coupled to the first conductor and the output signal line is coupled to the second conductor, the second conductor carries the electrical signals along with electrical noise of reduced amplitude within a range of frequencies. The device also includes a tuner coupled to the housing and configured to adjust a capacitance of the variable capacitor, wherein adjusting the capacitance of the variable capacitor adjusts the range of frequencies.

An apparatus and method for a frequency based integrated circuit that selectively filters out unwanted bands or regions of interfering frequencies utilizing one or more tunable notch or bandpass filters or tunable low or high pass filters capable of operating across multiple frequencies and multiple bands in noisy RF environments. The tunable filters are fabricated within the same integrated circuit package as the associated frequency based circuitry, thus minimizing R, L, and C parasitic values, and also allowing residual and other parasitic impedance in the associated circuitry and IC package to be absorbed and compensated.

A communication system includes a demodulator configured to demodulate a modulated signal responsive to a first carrier signal. The demodulator includes a filter and a gain adjusting circuit. The filter is configured to generate a filtered first signal based on a first signal. The first signal is a product of the first carrier signal and the modulated signal. The filter has a gain adjusted based on a set of control signals. The gain adjusting circuit is coupled to the filter, and is configured to generate the set of control signals based on at least a voltage of the filtered first signal. The gain adjusting circuit includes a first peak detector coupled to the filter. The first peak detector is configured to output a peak value of the voltage of the filtered first signal.

A method of constructing an RF filter comprises designing an RF filter that includes a plurality of resonant elements disposed, a plurality of non-resonant elements coupling the resonant elements together to form a stop band having a plurality of transmission zeroes corresponding to respective frequencies of the resonant elements, and a sub-band between the transmission zeroes. The non-resonant elements comprise a variable non-resonant element for selectively introducing a reflection zero within the stop band to create a pass band in the sub-band. The method further comprises changing the order in which the resonant elements are disposed along the signal transmission path to create a plurality of filter solutions, computing a performance parameter for each of the filter solutions, comparing the performance parameters to each other, selecting one of the filter solutions based on the comparison of the computed performance parameters, and constructing the RF filter using the selected filter solution.

Techniques for creating a low pass filter associated with a flux line are presented. A qubit device can comprise a first substrate and second substrate. A low pass filter, comprising at least one inductor and at least one capacitor can be formed, wherein respective components of or associated with the low pass filter can be formed on the first or second substrates, and wherein one or more bump bonds can extend between the substrates to connect respective components that are on respective substrates. The filter can receive an input signal via an input line and filter the signal to produce a filtered signal as output to a flux line that is in proximity to a coupler with SQUID loop and one or more flux-tunable qubits that are formed on one of the substrates. The filter can reduce electrical noise and Purcell decay associated with the flux line.

A hybrid compensation system is electrically connected between a power grid and a load. The hybrid compensation system includes an active filter, a passive filter and a control unit. The active filter generates an output current. The active filter includes a switching circuit, a DC bus capacitor and a filtering inductor. The control unit includes a voltage controller, a first reactive current detector, a harmonic current compensator, a current loop controller and a modulator. The voltage controller generates a first current given signal according to a bus voltage of the DC bus capacitor and a reference voltage. The first reactive current detector generates a second current given signal. The harmonic current compensator generates a third current given signal. The current loop controller generates a control signal. The modulator generates a driving signal according to the control signal.

The present application provides a wind turbine and a converter filter capacitor switching control method, device and system therefor. The method includes: acquiring a contactor delay influence factor of the converter and an approximate zero voltage period of the power grid connected to the wind turbine, wherein an absolute value of a voltage of the power grid in the approximate zero voltage period is less than an approximate zero voltage threshold; obtaining a contactor delay duration according to the contactor delay influence factor, wherein the contactor delay duration is a duration from when the contactor receives a switching instruction to when the contactor is switched on or off; determining a switching time point of the filter capacitor based on the approximate zero voltage period and the contactor delay duration; transmitting the switching instruction to the contactor when the switching time point is reached.

A multi-bank array type capacitor circuit is provided. The capacitor circuit includes a first cap bank including first to m.sup.th switch-capacitor circuits which are connected in parallel with each other, wherein the first to m.sup.th switch-capacitor circuits have different capacitances based on a first weight; and a second cap bank, connected in parallel with the first cap bank, and including first to m.sup.th switch-capacitor circuits which are connected in parallel with each other, wherein the first to m.sup.th switch-capacitor circuits have different capacitances based on a second weight that is different from the first weight.

The disclosure relates to an electrical component, for example, a surface-mount resonator, including a distributed-element circuit disposed on a dielectric base and separated from an electromagnetic field modification member by a gaseous gap, wherein a frequency characteristic of the electrical component can be tuned by positioning the electromagnetic field modification member relative to the distributed-element circuit using an actuator.

A communication system includes a transmitter configured to transmit a modulated signal, a transmission line configured to carry the modulated signal, and a receiver coupled to the transmitter by the transmission line, and configured to receive the modulated signal. The transmitter includes a modulator configured to generate the modulated signal responsive to a data signal and a carrier signal. The receiver includes a demodulator configured to demodulate the modulated signal responsive to a first carrier signal. The demodulator includes a filter and a gain adjusting circuit configured to adjust a gain of the filter, and to generate the set of control signals based on a voltage of the filtered first signal and a voltage of the first signal. The gain adjusting circuit includes a first peak detector coupled to the filter, and configured to detect a peak value of the voltage of the filtered first signal.