75 results about "Shunt capacitors" patented technology

The present disclosure relates to a current sensing system for a magnetic resonance imaging (MRI) scanner operating at 1H and 23Na resonant frequencies. The system includes a dual-tuned RF coil with a network of up to two parallel quarter-wavelength transmission lines, each integrated with a PIN diode-coupled shunt capacitor. A multiple half-wavelength transmission line is employed with a corresponding pair of shunt capacitors and PIN diodes. A quarter-wavelength transmission line, coupled with a power amplifier through a matching network of shunt capacitors and PIN diodes, is also included. The configuration parameters are designed to tune the system to the fundamental frequency and its first odd multiple, correlating with the 1H resonant frequency, and to the 23Na resonant frequency. The system accurately senses coil currents by detecting voltage variations in the matching network, thereby facilitating precise current measurements at the tuned resonant frequencies without the need for external sensors.

An example power splitter and associated methods are provided herein. In some embodiments, the power splitter may include a first port. In some embodiments, the power splitter may include a plurality of second ports. In some embodiments, the power splitter may include one or more low pass elements. In this regard, the one or more low pass elements may include at least one series inductor and at least one shunt capacitor. In some embodiments, the power splitter may include one or more high pass elements. In this regard, the one or more high pass elements may include at least one series capacitor and at least one shunt inductor. In some embodiments, each of the one or more high pass elements and each of the one or more low pass elements is electrically connected to the first port and the plurality of second ports.

A current sensing system for a magnetic resonance imaging (MRI) scanner operating at 1H and 31P resonant frequencies includes a dual-tuned RF coil with a network of up to two parallel quarter-wavelength transmission lines, each integrated with a PIN diode-coupled shunt capacitor. A multiple half-wavelength transmission line is employed with a corresponding pair of shunt capacitors and PIN diodes. A quarter-wavelength transmission line, coupled with a power amplifier through a matching network of shunt capacitors and PIN diodes, is also included. The configuration parameters are designed to tune the system to the fundamental frequency and its first odd multiple, correlating with the 1H resonant frequency, and to the 31P resonant frequency. The system accurately senses coil currents by detecting voltage variations in the matching network, thereby facilitating precise current measurements at the tuned resonant frequencies without the need for external sensors.

The invention discloses an underwater wireless transmission system multi-parameter online identification energy efficiency improvement method, which comprises the following steps: firstly, constructing a topological graph of an underwater wireless power transmission system, when the system works normally, acquiring voltage U1 and current I1 of a transmitting coil, and calculating input impedance; determining an equivalent circuit, and establishing an equation of a mutual inductor M, a bridging capacitor Ce and an equivalent load RLe through the voltage U1 and the current I1; and solving the mutual inductance M, the bridging capacitor Ce and the equivalent load RLe to realize multi-parameter identification. According to the technology, the driving frequency of a system does not need to be changed, a complex circuit does not need to be added, and the identification requirements of mutual inductance, bridging capacitance and load can be rapidly and accurately met. Afterwards, the working state of the system is judged according to the obtained bridging capacitance value, the method can accurately control the power and efficiency of the system, and the stability and reliability of the charging process are improved.

A Doherty power amplifier (PA) includes a main amplifier, an auxiliary amplifier, and a power splitting and phase shifting circuit configured to receive an input radio frequency (RF) signal, split the input RF signal into a first RF signal and a second RF signal, output the first RF signal to an input of the main amplifier, output the second RF signal to an input of the auxiliary amplifier, and provide a phase shift between the first RF signal and the second RF signal. The Doherty PA also includes a shunt inductor coupled to an output of the main amplifier, a shunt capacitor coupled to an output of the auxiliary amplifier, and a transformer. The transformer includes a first inductor coupled between the output of the main amplifier and the output of the auxiliary amplifier, and a second inductor magnetically coupled with the first inductor.

The invention relates to a notch filter for wireless circuitry. In particular, the wireless circuitry may include one or more notch filters. The notch filter circuit may include a series inductor having a first terminal coupled to an input and having a second terminal coupled to an output; a first series capacitor having a first terminal coupled to the input and having a second terminal coupled to a node; a second series capacitor having a first terminal coupled to the output terminal and having a second terminal coupled to the node; and a shunt resistor having a first terminal coupled to the node and having a second terminal coupled to a ground line. The notch filter may also include a shunt capacitor coupled in series with the shunt resistor located between the node and the ground line. The shunt resistor may be an adjustable resistor.

The invention discloses an antenna tuning matching network circuit of a mobile platform short wave shunt-fed antenna and a tuning method of the antenna tuning matching network circuit. The circuit comprises a series inductor L1, a series capacitor C2, a parallel inductor L2 and a parallel capacitor C1, one end of the series inductor L1 is connected with one end of a shunt-fed antenna, the other end of the series inductor L1 is connected with one end of the series capacitor C2, and the other end of the series capacitor C2 is connected with one end of a power amplifier; the common end of the series inductor L1 and the series capacitor C2 is connected to one end of the parallel inductor L2 and one end of the parallel capacitor C1. The other end of the shunt inductor L2 is connected with the other end of the shunt capacitor C1, and the common end is connected to the other end of the shunt-fed antenna and the other end of the power amplifier. According to the input impedance admittance data of the mobile platform short-wave shunt-fed antenna, tuning is carried out in multiple frequency band ranges. According to the invention, perfect matching of the short-wave shunt-fed antenna which shows strong capacitance in a high frequency band and even has a second resonance point is realized, so that the tuning capability of the antenna tuner is improved, and the communication effect is improved.

Apparatus and methods for load mismatch compensation of power amplifiers are disclosed. In certain embodiments, a power amplifier system includes a power amplifier having an output coupled to an antenna through a mismatch compensation circuit. The mismatch compensation circuit includes a bank of switchable shunt capacitors and a bank of switchable series capacitors, with the bank of switchable series capacitors connected between the output of the power amplifier and the bank of switchable shunt capacitors.

The invention discloses a self-healing parallel capacitor aging test device and method for an AC power system. The method comprises the following steps: S1, preparation before test; s2, carrying out a first-stage aging test; s3, carrying out a charge-discharge cycle test; s4, performing a second-stage aging test; and S5, detecting after the test. According to the self-healing parallel capacitor aging test device and method for the alternating-current power system, automatic control over the whole test process is achieved, it is guaranteed that test conditions meet the national standard requirement, the influence and closing impact on a power grid in the test process are eliminated, the accuracy and reliability of a test result are improved, and the test efficiency is improved. A standardized method is provided for performance evaluation of the capacitor, and the problems that an existing test device is low in integration and automation degree, poor in test precision, large in power grid influence and insufficient in safety protection are solved.

The invention relates to a low noise crystal oscillator. A crystal oscillator has a regulator for receiving a first power supply voltage and outputting a second power supply voltage; the source follower is used for receiving the second power supply voltage and outputting a third power supply voltage according to the control voltage; the first inverter operates at a third power supply voltage and is used for receiving the first oscillation signal at the first node and outputting a second oscillation signal at the second node. The second inverter operates at a third power supply voltage and is used for receiving a second oscillation signal at a second node and outputting a third oscillation signal. The crystal is arranged across the first node and the second node; the first shunt capacitor is used for shunting the first node to a ground terminal; the second shunt capacitor is used for shunting the second node to the grounding end; and the clock low-pass filter is used for outputting a control voltage according to the pulse signal.

The present invention discloses a wireless power transmission method and device with variable coupling coefficient stability. The method and device include a primary-side rectifier and filter unit, a primary-side high-frequency inverter, a primary-side DC / DC unit, a primary-side linear topology structure, a primary-side transmitting coil, a secondary-side receiving coil, a secondary-side shunt capacitor, a secondary-side variable inductor or capacitor structure, and a secondary-side rectifier and filter unit. The secondary-side variable inductor or capacitor structure includes at least one linear inductor L2 or linear capacitor C3 operating in a switching state. The output voltage waveform of the present invention is between a sine wave and a square wave, and can achieve automatic voltage stabilization and spectrum spread under variable coupling coefficient conditions without the involvement of active control devices. The stability of this system does not rely on communication feedback, has high reliability, and is low in cost. It can maintain high efficiency and stability of wireless power transmission when the coupling coefficient changes.

The invention discloses a cable sequence shunt capacitance calculation method. The method comprises the following steps: (1) constructing a cable full-dimensional shunt capacitance matrix; (2) calculating elements in the full-dimensional shunt capacitance matrix of the cable; (3) calculating a cable phase shunt capacitance matrix according to the cable full-dimensional shunt capacitance matrix in combination with a cable connection mode and a grounding mode; and (4) according to the cable phase shunt capacitor matrix, calculating a sequence shunt capacitor matrix through phase sequence conversion, wherein diagonal elements of the sequence shunt capacitor matrix are sequence shunt capacitors. According to the invention, cable structure differences are fully considered, and capacitive coupling among conductor layers of a single-core cable with an armor layer, a single-core cable without an armor layer and a three-core cable is analyzed; according to the method, the difference between a cable connection mode and a grounding mode is fully considered, the influence of fixed connection, single-point connection and cross connection on capacitance distribution is analyzed, the comprehensiveness of cable sequence shunt capacitance calculation is greatly improved, most of cables with different structures and connection modes can be covered, and the method has a good application effect in practical engineering.

A battery power supply (BPS) circuit to power an intermittently powered load, optimized to maximize battery capacity utilization and extend battery life, while offering low temperature performance. The BPS includes a voltage converter connected to a battery for generating a voltage greater or less than the battery voltage, a current limiter configured to limit current in a current limiting mode and to provide a shunt in a noncurrent limiting mode, a capacitor tank for providing an output voltage to the load and first charged to a voltage up to 95 or 100% (depending upon the operation of the BPS) of a desired output voltage, and second charged to the desired output voltage when the current limiter is shunted.

An apparatus includes an interface receiving a plurality of voltage measurements that include one combination of a first voltage measurement and a second voltage measurement; a first voltage measurement at a first tap point of a shunt capacitor bank; a second voltage measurement at the bus, wherein the shunt capacitor system is a single y-connected shunt capacitor bank comprising the shunt capacitor bank; a first voltage measurement at a first tap point of a first y-connected branch; a second voltage measurement at a second tap point of a second y-connected branch; wherein the shunt capacitor system is a double y-connected shunt capacitor bank comprising the first y-connected branch and the second y-connected branch; and, a fault identifier identifying a simultaneous fault of the shunt capacitor system based upon a temporal evolution of the first and second voltage measurements.

The utility model relates to the field of low-voltage parallel capacitors, and discloses a high-safety low-voltage parallel capacitor which comprises a cylindrical shell, a core rod coaxial with the shell is arranged in the shell, a capacitor assembly is arranged on the periphery of the core rod, and a wire holder electrically connected with the capacitor assembly is arranged above the capacitor assembly. An explosion-proof belt which is recessed towards the inside of the shell is fixed on the peripheral side wall of the shell, when the capacitor assembly is heated to drive the shell to expand, the explosion-proof belt is straightened from a folded state, the connection between the capacitor assembly and the wiring section terminal is broken by expansion of the shell, and the capacitor assembly does not continue to heat any more. The risk that the shell continues to expand and explode is avoided, and the use safety performance of the low-voltage parallel capacitor is improved.

The invention discloses automobile sound equipment and a noise reduction method thereof, and belongs to the technical field of automobile noise reduction. The sound equipment comprises a loudspeaker, and a noise reduction control circuit, an audio playing circuit and a control chip which are electrically connected with the loudspeaker, the loudspeaker comprises a driving unit, a positive electrode interface and a negative electrode interface; the noise reduction control circuit comprises a shunt resistor, a shunt capacitor and a shunt inductor which are sequentially connected in series; wherein the shunt resistor is connected with the positive electrode interface through the first execution chip, and the shunt inductor is connected with the negative electrode interface through the second execution chip; the output end of the audio playing circuit is connected with the positive electrode interface through the first execution chip, and the backflow end of the audio playing circuit is connected with the negative electrode interface through the second execution chip. The control chip controls the first execution chip and the second execution chip to be switched synchronously, so that one of the audio playing circuit and the noise reduction control circuit is switched on. According to the invention, the loudspeaker is used for active noise reduction in the non-audio playing state through circuit switching, and no extra noise reduction equipment needs to be installed.

The utility model relates to the field of capacitors, in particular to a self-healing type low-voltage parallel capacitor, which comprises a metal shell, a base, a top seat, wire outlet sleeves, wire ends, a capacitor main core group, a partition plate and a capacitor secondary core group, the base is mounted on the lower side of the metal shell, the top seat is mounted on the upper side of the metal shell, and the three wire outlet sleeves with the same specification are mounted on the upper side of the top seat. Three partition plates are installed on the inner side of the metal shell, three capacitor main core sets are installed on the partition plates in a partitioned mode, capacitor secondary core sets are installed on the two sides of each capacitor main core set, a slotted hole is formed in the middle of each capacitor main core set, a fuse is installed in each slotted hole, grooves are formed in the upper end and the lower end of each capacitor main core set, and metal head branch-shaped objects are installed in the grooves. A metal head branch-shaped object and a fuse are arranged inside, fault diffusion is avoided, and safety is improved.

Apparatus and methods for power amplifier systems with balun and shunt capacitor are disclosed. In certain embodiments, a front-end system includes a shunt capacitor, a balun having an input side and an output side, and power amplifier stages that operate in parallel with one another to amplify a radio frequency input signal. The power amplifier stages include a first power amplifier stage having a first output coupled to the shunt capacitor and to a first input terminal on the input side of the balun, and a second power amplifier stage having a second output coupled to a second input terminal on the input side of the balun.

This application discloses a charging pile and its control method, relating to the field of DC charging technology. The charging pile includes a three-phase parallel resonant converter, a controller, and a relay control circuit. The three-phase parallel resonant converter is connected to both the controller and the relay control circuit. The three-phase parallel resonant converter includes three independent and structurally identical conversion units. Each conversion unit includes an input rectifier bridge, a resonant circuit, an isolation transformer, and a rectifier circuit connected in sequence. The resonant circuit includes a choke coil, a switching transistor, a shunt capacitor, a resonant capacitor, and a resonant coil. The rectifier circuit includes a rectifier capacitor, a diode, a filter capacitor, a first filter coil, and a second filter coil. The controller is used for: soft-start control of the output voltage and output current during the startup phase, and control of the series and parallel connection state of the relay control circuit; and for performing input-side and output-side regulation and drive wave generation control during the operation phase. This application has the advantages of high power density, small size, and simple control.

The application discloses a commutation margin hybrid compensation system, method and device and related equipment, and the system comprises at least one 12-pulse converter bridge, at least two converter transformers, a smoothing reactor, a network-side AC bus, at least two commutation margin hybrid compensation devices, the commutation margin hybrid compensation device comprising a valve-side AC bus, a shunt capacitor bank and at least one current source converter; the shunt capacitor bank and the current source converter are both connected in parallel on the valve-side AC bus; the shunt capacitor bank is configured to provide reactive compensation to the 12-pulse converter bridge and filter out high-order harmonics; the current source converter is configured to increase the actual extinction angle of the 12-pulse converter bridge by outputting a preset harmonic current. The scheme effectively increases the commutation margin, reduces the risk of commutation failure, accurately compensates for reactive power and harmonics nearby, saves the traditional AC filter, reduces the occupied area, and reduces the loss and cost.

This invention discloses a method for equalizing the branch impedance of a parallel capacitor bank, comprising: determining parameters such as the connection position of each capacitor branch on the positive and negative busbars, and the input and output positions of the positive and negative busbars; and balancing the impedance of the first capacitor branch with the second capacitor branch. i The total equivalent impedance of each capacitor branch is decomposed into busbar path impedance, capacitor body impedance, and connector distributed impedance. Based on the connection location and busbar inlet / outlet positions, the corresponding busbar path impedance is calculated or extracted. Based on the busbar path impedance, capacitor body impedance, and adjustable range of connectors for multiple capacitor branches, the total impedance of the target branch is determined. The impedance of the first capacitor branch is then calculated inversely based on the total impedance of the target branch. i The invention addresses the impedance compensation required for each capacitor branch and determines the corresponding connector configuration scheme based on the target impedance compensation. This invention brings the total equivalent impedance of multiple capacitor branches closer to uniformity, achieving branch impedance balancing in parallel capacitor banks.

The present invention provides an equivalent circuit for switching a 66kV parallel capacitor bank in a 500kV substation, which belongs to the field of overvoltage technology in the field of electrical engineering. The equivalent circuit includes an equivalent inductance L of a series reactor, a capacitance C1 of a series reactor to ground, and an equivalent capacitance C1 of a capacitor bank. ∑ , switch K, equivalent power supply G and equivalent inductor L on the power supply side G Among them, the equivalent capacitance of the capacitor bank C ∑ It is the parallel capacitor group C, the parallel capacitor group neutral point to ground capacitance C CN After connecting in series, the capacitance C of the capacitor group to ground is connected in parallel C The equivalent capacitance of the three is calculated. This equivalent circuit solves the problems of inaccurate equivalent circuits for switching 66kV shunt capacitor banks when SF6 circuit breakers are used, as well as inaccurate transient process parameters for shunt capacitors and their series reactors. This provides a technical method for effectively preventing and controlling reactive equipment failures or accidents, and also offers valuable guidance for developing or evaluating insulation protection configuration measures.

A plasma processing apparatus is provided. The plasma processing apparatus includes a chamber having a processing space defined therein in which plasma is generated; and a plasma generation unit configured to excite gas in the processing space into a plasma state, wherein the plasma generation unit includes: a first power supply to supply power for generation of the plasma; a coil connected to the first power supply; a first shunt capacitor disposed between and connected to a first node of the coil and a ground; and a second shunt capacitor disposed between and connected to a second node other than the first node of the coil and the ground.

A crystal oscillator having a voltage regulator configured to receive a first power supply voltage and output a second power supply voltage; a source follower configured to receive the second power supply voltage and output a third power supply voltage in accordance with a control voltage; a first inverter operating under the third power supply voltage and configured to receive a first oscillatory signal from a first node and output a second oscillatory signal at a second node; a second inverter operating under the third power supply voltage and configured to output a third oscillatory signal; a crystal placed across the first node and a second node; a first shunt capacitor configured to shunt the first node to ground; a second shunt capacitor configured to shunt the second node to ground; and a clocked lowpass filter configured to output the control voltage in accordance with the pulsed signal.

Wireless circuitry can include one or more notch filters. A notch filter circuit can include a series inductor having a first terminal coupled to an input and having a second terminal coupled to an output, a first series capacitor having a first terminal coupled to the input and having a second terminal coupled to a node, a second series capacitor having a first terminal coupled to the output and having a second terminal coupled to the node, and a shunt resistor having a first terminal coupled to the node and having a second terminal coupled to a ground line. The notch filter can further include a shunt capacitor coupled in series with the shunt resistor between the node and the ground line. The shunt resistor can be a tunable resistor.

This disclosure relates to devices, wireless communication apparatuses, methods, and circuit systems for T-type switches with gate shunts. One aspect is a device including a first differential switch having a control input. The device also includes a second differential switch coupled to the first differential switch, the second differential switch being the control input. A shunt capacitor is coupled between a first output and a second output of the first differential switch and a first input and a second input of the second differential switch. The first shunt switch, having control inputs, inputs, and outputs, has inputs and outputs coupled to the control input of the first differential switch. The second shunt switch, having control inputs, inputs, and outputs, has inputs and outputs coupled to the control input of the second differential switch.

The utility model belongs to the technical field of electrical equipment, and particularly relates to an SH-E series elliptical self-healing low-voltage parallel capacitor device, which comprises a frosted tinplate shell group, and a power screw is fixed on the upper side of the frosted tinplate shell group. The device is composed of the frosted tinplate shell group, the power supply screw rod, the grounding terminal, the resistor, the explosion-proof security sheet, the braided copper wire, the metallized polypropylene film and the flame-retardant soft resin adhesive, so that disasters can be effectively prevented and isolated, the dry design is pollution-free, and the use safety is ensured; the loss is very low, and the service life is long; a self-recovery function, an over-temperature protection function and a unique protection system are provided, the weight is light, the structure is simple, the size is small, the operation is convenient, the voltage quality can be effectively improved, the power factor is improved, and the system power supply capability is improved; the improved capacitor device comprises an upper module and a lower module, can be quickly assembled and disassembled, and is extremely convenient to repair and maintain.

The present application relates to a kind of district reactive power multi-objective control method, device, equipment and medium, wherein, method includes: obtaining first active power and first reactive power, and calculating first power factor;Obtain distribution transformer side input active power to calculate line loss, and according to line loss situation, calculate the power factor after being compensated by district capacitor;Calculate the switching amount of first shunt capacitor in low-voltage side of district, and select the capacitor with appropriate capacity as switching object to switch;Monitor the power factor angle of district transformer low-voltage side after capacitor switching, and according to monitoring situation, increase the switching amount of second shunt capacitor;When the capacity of shunt capacitor in low-voltage side cannot meet the demand, calculate the gap of reactive power capacity, and include the regulation range of distributed photovoltaic reactive power regulation capability in district.The present application meets the requirements of first end and district operating power factor of medium-voltage transmission line while reducing the line loss of medium-voltage transmission line.

The invention discloses a power supply module application circuit adopting a power and control separation architecture, relates to the field of power supply equipment, and aims to solve the problem of a power supply mode of a high-integration and low-power-consumption phased-array antenna, low voltage and a large circuit. The system comprises a control module and a power module. One control module is at least connected with one power module and at most connected with 16 power modules which are connected in parallel; according to the control module, a VIN12V pin is connected with a first shunt capacitor circuit; the ADDRESS pin is connected with the first series circuit; the PROG pin is connected with the second series circuit; the vBOOT pin is connected with the third series circuit; the FAULT pin is used for fault alarm; the SENSE pin is used for voltage sampling; the AUX5V pin and the TEMP pin are used for connecting a power module; the EN pin is used for switching on and off, the VREF is used for connecting reference voltage, the PWM6 pin and the PWM7 pin are used for phase driving, and the CS6 pin and the CS7 pin are used for current sampling. According to the invention, a low-voltage and large-current power supply mode is realized.

A quantum circuit and related manufacturing method are disclosed. The quantum circuit includes a vertical Josephson junction (1001) formed by a bottom electrode (810) in the first superconducting material layer, a tunnel barrier (830), and a top electrode (820) in the second superconducting material layer. A contact portion (811) and a coupling portion (812) of the bottom electrode are respectively located inside and outside the Josephson junction. The transport sub-qubit of the quantum circuit comprises a Josephson junction (101) and a shunt capacitor formed from contacts of a top electrode and a bottom electrode as shunt capacitor plates. The readout circuit is capacitively coupled to the bottom electrode through the coupling and includes a coupling head (861). The coupling portion is fitted into the recess of the coupling head. The top electrode is configured as a floating electrode and is not resistance-coupled to the first superconducting material layer.