Showing papers on "RLC circuit published in 2007"

Three-Level Z-Source Inverters Using a Single LC Impedance Network

Abstract: Three-level Z-source inverters are recent single-stage topological solutions proposed for buck-boost energy conversion with all favorable advantages of three-level switching retained. Despite their effectiveness in achieving voltage buck-boost conversion, existing three-level Z-source inverters use two LC impedance networks and two isolated dc sources, which can significantly increase the overall system cost and require a more complex modulator for balancing the network inductive voltage boosting. Offering a number of less costly alternatives, this letter presents the design and control of two three-level Z-source inverters, whose output voltage can be stepped down or up using only a single LC impedance network connected between the dc input source and either a neutral-point-clamped (NPC) or dc-link cascaded inverter circuitry. Through careful design of their modulation scheme, both inverters can function with the minimum of six device commutations per half carrier cycle (similar to that needed by a traditional buck three-level NPC inverter), while producing the correct volt-sec average and inductive voltage boosting at their ac output terminals. Physically, the designed modulation scheme can conveniently be implemented using a generic "alternative phase opposition disposition" carrier-based modulator with the appropriate triplen offset and time advance/delay added. The designed inverters, having a reduced passive component count, are lastly tested in simulation and experimentally using a laboratory prototype with the captured results presented in a later section of the letter

A wireless autonomous device system

Abstract: A method of powering a wireless autonomous device having energy harvesting circuitry, on-board electronic circuitry, and RF transmitter circuitry using an RF transmitting profile that includes a plurality of RF pulses. That same profile may also be used to simultaneously communicate information to the wireless autonomous device in a number of ways, including different encoding schemes. A system including a plurality of wireless autonomous devices that employs the methods is also provided. Further, a method of designing a wireless autonomous device system and/or a wireless autonomous device to be used therein is provided that employs an equivalent circuit for the wireless autonomous device that is in the form of a lumped parameter RLC circuit with an energy source.

System and method for generating radio frequency energy

Abstract: An electrosurgical generator is disclosed. The electrosurgical generator includes a power supply for generating a DC voltage. The electrosurgical generator also includes a first parallel inductor-capacitor circuit being driven by a first signal at a first predetermined frequency and a second parallel inductor-capacitor inductor-capacitor circuit driven by a second signal at the first predetermined frequency phase shifted 180°. The electrosurgical generator further includes a series inductor-capacitor resonant circuit operably connected in series with a primary winding of a transformer. The first and second parallel inductor-capacitor circuits are operably connected to the transformer, such that the first inductor-capacitor circuit generates a positive half sine wave and the second inductor-capacitor circuit generates a 180° phase-shifted positive half sine wave to generate a full sine wave in a secondary winding of the transformer.

Wireless ic device and component for wireless ic device

Abstract: A wireless IC device includes a wireless IC chip, a power supply circuit board upon which the wireless IC chip is mounted, and in which a power supply circuit is provided, the power supply circuit includes a resonant circuit having a predetermined resonant frequency, and a radiation pattern, which is adhered to the underside of the power supply circuit board, for radiating a transmission signal supplied from the power supply circuit, and for receiving a reception signal to supply this to the power supply circuit. The resonant circuit is an LC resonant circuit including an inductance device and capacitance devices. The power supply circuit board is a multilayer rigid board or a single-layer rigid board, and between the wireless IC chip and the radiation pattern is connected by DC connection, magnetic coupling, or capacitive coupling.

Design and Modeling of Patch Antenna Printed on Magneto-Dielectric Embedded-Circuit Metasubstrate

Abstract: The design and modeling of an embedded-circuit metamaterial with epsi-mu constitutive parameters as the substrate for patch antennas is presented. The magneto-dielectric metasubstrate is constructed of periodic resonant loop circuits embedded in a low dielectric host medium, and is capable of providing both permittivity and permeability material parameters at any frequency of interest. The embedded-circuit building blocks are very small in size (

A New Resonant Gate Drive Circuit for Synchronous Buck Converter

Abstract: This paper proposes a new resonant gate drive circuit for driving both the control metal oxide semiconductor field effect transistor (MOSFET) and synchronous MOSFET in a synchronous buck converter. The circuit can recover more than 70% of the conventional gate drive loss. More importantly, the driving circuit can also reduce the switching loss. It charges and discharges the gate of MOSFET at a constant current during switching interval. Other advantages of the proposed circuit include better noise immunity for dv/dt turn on, less sensitive to parasitic track inductance. The experimental prototype shows that the loss reduction is 10% of the output power for 12 V input, 1.5 V/15 A output with switching frequency of 1 MHz.

Passive cooling of a micromechanical oscillator with a resonant electric circuit.

Abstract: We cool the fundamental mode of a miniature cantilever by capacitively coupling it to a driven rf resonant circuit. Cooling results from the rf capacitive force, which is phase shifted relative to the cantilever motion. We demonstrate the technique by cooling a 7 kHz cantilever from room temperature to 45 K, obtaining reasonable agreement with a model for the cooling, damping, and frequency shift. Extending the method to higher frequencies in a cryogenic system could enable ground state cooling and may prove simpler than related optical experiments in a low temperature apparatus.

Low Frequency Pulsed Resonant Converter for Energy Harvesting

Abstract: A pulsed-resonant ac-dc converter and an integrated circuit (IC) controller have been designed, fabricated, and tested for harvesting energy from low-voltage (1.2V), low-power (1-100muW) energy transducers with output frequency in the 10-Hz-1-kHz range. Simulations using foundry models suggest that the silicon loss could be as low as 0.6muW, and the efficiency could reach 70%. With the IC experimentally packaged, the measured efficiency is between 50% and 70%, depending on the size and the loss in the resonant inductor

Radio ic device and radio ic device part

Abstract: It is possible to provide a radio IC device and a radio IC device part having stable frequency characteristic. The radio IC device includes: a radio IC chip (5); a feed circuit substrate (10) having the radio IC chip (5) mounted thereon and a feed circuit (16) containing a resonance circuit having a predetermined resonance frequency; and an emission plate (20) bonded to the lower surface of the feed circuit substrate (10) for emitting the transmission signal supplied from the feed circuit (16) and supplying the reception signal to the feed circuit (16). The resonance circuit is formed by an LC resonance circuit having an inductance element (L) and capacitance elements (C1, C2). The feed circuit substrate (10) is a multi-layer or single-layer rigid substrate and connected to the radio IC chip (5) and the emission plate (20) by DC coupling, magnetic coupling, or capacity coupling.

Electromagnetic-coupling-module-attached article

Abstract: An electromagnetic-coupling module including a radio IC chip and a feeder circuit board on which the radio IC chip is mounted and a feeder circuit including a resonant circuit having a predetermined resonant frequency is attached to an article. The article has a radiation element that radiates a transmission signal supplied from the feeder circuit of the electromagnetic-coupling module via electromagnetic coupling and that supplies a received reception signal to the feeder circuit via the electromagnetic coupling.

Article provided with electromagnetically coupled module

Abstract: Provided is an article having an electromagnetically coupled module, which has a built-in wireless IC chip and stable frequency characteristics. An electromagnetically coupled module (1a) is composed of a wireless IC chip (5), and a feed circuit board (10), which has the wireless IC chip (5) mounted thereon and a feed circuit (16) including a resonance circuit having a prescribed resonance frequency. The electromagnetically coupled module is mounted on an article. The article is provided with a radiation plate (20), which radiates a transmission signal supplied from the feed circuit (16) of the electromagnetically coupled module (1a) through electromagnetic coupling and supplies the received signal to the feed circuit (16) through electromagnetic coupling.

High Voltage Power Supply for Ozone Generation Based on Piezoelectric Transformer

Abstract: Even though, nowadays, piezoelectric transformers (PTs) are only available with low power rating, there exist several low-power applications of ozone generation in which the use of this novel technology could be advantageous. Hence, the aim of this paper is to evaluate the possibilities of using PTs in the implementation of high-voltage power supplies for ozone generation. First, the possible topologies that can be used to drive the PT are identified. Then, the half-bridge inverter operating under zero-voltage switching (ZVS) is investigated, and the effect of the silent discharge generator (SDG) on the converter operation is analyzed. A new control circuit that allows the ZVS operation is proposed. The control circuit operates in closed loop by measuring the phase between the PT's resonant current and the switching pattern and adjusting the switching frequency to the optimum value to assure ZVS. A laboratory prototype for a 6-W SDG was tested, and obtained experimental results are shown.

Compensated circuit with characteristics of lossless double negative materials and its application to array antennas

Abstract: A compensated circuit showing the characteristics of lossless double negative (DNG) materials is proposed and applied to an active integrated antenna array. A properly selected matching circuit produces the phase advance, which is characteristic of a left-handed wave (backward-wave), and the lossy resonant circuit generates the negative group velocity. An amplifier is used to compensate for the inherent loss of the resonant circuit, including its resistor. Then, a series-fed antenna array with a proposed DNG circuit is also designed and fabricated. It consists of two subarrays, each made of two aperture-coupled patch antennas, and the DNG circuit block inserted between the subarrays. In comparison to a conventional array, without the DNG circuit whose two subarrays are connected directly by a microstrip line, the proposed array shows a negligible beam squint and flat gain, over a considerable bandwidth of 11%.

Zero-Voltage-Switching Multiresonant Three-Level Converters

Abstract: This paper proposes a family of zero-voltage-switching multiresonant three-level converters (ZVS-MR-TLCs), which are derived by adding a ZVS-MR multiresonant network to the TLCs. The arrangement of a multiresonant network results in the absorption of all the major parasitic components in the resonant circuit, including the switch output capacitor, diode junction capacitor, and transformer leakage inductor. Compared with the two-level multiresonant converters (MRCs), the proposed converters achieve ZVS in a wider load range and reduce the voltage stress on the switches and diodes, and the filter can be reduced significantly. The Buck ZVS-MR-TLC is taken as the example to illustrate the operation principle, characteristics, and advantages over the two-level Buck ZVS-MRC. An interleaved control strategy and a voltage control of the flying capacitor for the new converters are presented in detail. A 1-kW high-voltage-input railway charger prototype converter is built in our lab to verify the theoretical analysis and the effectiveness of the interleaved control strategy and flying capacitor voltage control method

A Robust One-Cycle Controlled Full-Bridge Series-Parallel Resonant Inverter for a High-Frequency AC (HFAC) Distribution System

Abstract: Resonant inverters are connected to a high-frequency AC (HFAC) bus, where power is delivered to different locations for points-of-use power management. Such a power distribution system subjects to more perturbations and load uncertainties than inverters operating with single load. A novel voltage control method is proposed in this paper for a high-frequency full-bridge resonant inverter with series-parallel resonant tank. A modified one-cycle controlled phase-shift modulation is proposed to effectively compensate the input line variations. The uncertainty model of the high frequency resonant inverter is developed and analyzed with the resonant circuit component tolerance, input line and load variations taken into design considerations. The voltage feedback controller is designed based on the Hinfin robust control theory and is implemented with analog discrete devices. The proposed control scheme has the advantages of fast response for both input line and load perturbations. It also ensures a wide range of system stability and guarantees robustness of the power converter. Both simulations and experimental results are provided to verify with the theoretical analysis through an experimental prototype of a full-bridge resonant inverter with an output power of 150-W operating at 1 MHz and an output voltage of 28 V (rms).

RF release mechanism for hard tag

Abstract: A releasable security tag for attachment to an article of merchandise includes: a locking mechanism with a release for attaching the tag to the article of merchandise; an EAS resonant circuit or an RFID circuit for responding to a first RF signal at a predetermined frequency corresponding to the resonant circuit or to the RFID circuit; an ambient RF energy harvesting circuit; a release signal detection circuit coupled to and powered by the ambient RF energy harvesting circuit and an electro-mechanical actuator electrically coupled to the release signal detection circuit. The electro-mechanical actuator releases the locking mechanism whenever the release signal detection circuit receives a release signal.

Power transmission for gastrointestinal microsystems using inductive coupling.

Abstract: Much research on the development of a robotic capsule and microrobot for the diagnosis of gastrointestinal diseases has been carried out. The powering of these microsystems is becoming very important as the implementation of such systems is becoming more feasible by advances in relevant technologies. A wireless power transmission system employing two coils, based on inductive coupling, is discussed in this note. The coupling coefficient between the two coils was measured on axial, lateral and pitch misalignment. The power transmission efficiency was deduced and optimized by selecting proper tuning capacitors and transmission frequency. A serial resonant circuit (SRC) on a receiving side is more adaptive by comparison with parallel resonant circuit (PRC) topology. A multi-receiving coil structure was proposed and examined in an attempt to resolve the orientation indetermination problem of a receiving coil. Experiments show that a dc power level up to 170 mW, with an efficiency of 1.3%, could be steadily received when the receiving coil was placed at the center of the transmitting coil, which can meet the requirement for electric power of some microsystems.

Resonance converter and synchronous rectification driving method thereof

Abstract: A resonance converter and a synchronous rectification driving method thereof are provided. The resonance converter includes a switch circuit having at least two first switches, a resonance circuit having a resonance frequency, a transformer, and a full-wave rectification circuit having two second switches each of which has a drain and a source and generates a channel resistance voltage when a current flows through the drain and the source. The synchronous rectification driving method includes steps as follow. When an operating frequency of the resonance converter is less than the resonance frequency and the resonance converter is coupled to a heavy load, the channel resistance voltage is compared with a reference voltage for driving the second switches of the full-wave rectification circuit; and when the operating frequency of the resonance converter is not smaller than the resonance frequency, duplicated signals of signals used to drive the first switches are respectively used to drive the second switches of the full-wave rectification circuit.

Electron coagulative scalpel

Abstract: FIELD: medical equipment. ^ SUBSTANCE: electron scalpel has manipulator, electrode for closing electric circuit, which circuit is connected with tissues to be coagulated, electric power circuit voltage rectifying circuit, which circuit applies rectified and direct voltage into radio-frequency circuit, which circuit is made for provision of main carrying frequency current signal at output, which frequency is defined by oscillator. Current signal is applied as signal, feeding manipulator, by means of radio-frequency transformer. Resulting signal, achieved as a result of combination of carrier frequency rectangular signal and modulating signal, is applied to manipulator. Resulting signal circulates in resonant circuit with wide band-pass at frequency of carrier frequency signal. Resulting signal have the same frequency as energy transmitted to blood to be coagulated. Energy has to be sufficient for increasing blood temperature subject to treatment. Fibrinogen denaturation, containing in tissue, can be performed to fibrin easier. ^ EFFECT: lower traumatism of surgical operation. ^ 14 cl, 3 dwg, 1 tbl

Discharge lamp lighting device

Abstract: There has conventionally been provided a discharge lighting device capable of performing dimming control of a hot cathode type discharge lamp. As a tube current is decreased, a filament temperature is decreased, and as the tube current is further decreased, discharge cannot be maintained, which in turn causes moving striations and flickering. The conventional device requires power supplies for controlling the tube current of the hot cathode type discharge lamp and for controlling a filament current, and has therefore a problem that a circuit becomes complicated, and the number of parts is increased, resulting in an increase in cost. In order to solve the above-described problem, an oscillation control circuit for determining a frequency with time constant of R and C; a L-C series resonant circuit connected to a half-bridge circuit operating at the frequency; and a circuit in which one ends of hot cathode filaments at both ends of a hot cathode type discharge tube are respectively connected in parallel with a resonant capacitor, and a capacitor is further connected in series to other ends of the filaments at the both ends of the hot cathode type discharge tube to perform lighting are provided, and nonstep dimming of the tube current is achieved by using a variable capacitance diode to change an oscillation frequency upon application of a DC dimming control voltage.

Series–Parallel Resonant Converter in Self-Sustained Oscillation Mode With the High-Frequency Transformer-Leakage-Inductance Effect: Analysis, Modeling, and Design

Abstract: An accurate modeling of the series-parallel resonant converter operating in self-sustained oscillation mode including the overlap effects of the output rectifying stage due to the leakage inductance of the transformer is presented. This paper presents a systematic procedure to study the aforementioned effects on the converter dynamic and steady-state performance. Such information is critical in designing isolated high-frequency resonance-based voltage-regulator modules for powering future subvoltage very large scale integration circuits such as microprocessors. The extended describing function technique is used to extract the steady-state characteristics in order to get an optimum converter design. Averaging state-space techniques are employed to derive a small-signal model that can describe the converter dynamics accurately. Analytical and simulation results are given. Finally, a 1-kW experimental prototype is built to verify the validity of the proposed work

Waveform analysis and delay prediction for a CMOS gate driving RLC interconnect load

Abstract: This paper deals with the problem of estimating the performance of a CMOS gate driving RLC interconnect load. The widely accepted model for CMOS gate and interconnect line is used for the representation. The CMOS gate is modeled by an Alpha Power law model, whereas the distributed RLC interconnect is represented by an equivalent @p-model. The output waveform and the propagation delay of the inverter are analytically calculated and compared with SPICE simulations. The analytical driver-interconnect load model gives sufficiently close results to SPICE simulations for two different cases of slow and fast input ramps. For each case of stimulation, the model gives an insight to four regions of operation of the CMOS gate. The voltage waveform at the end of an interconnect line is obtained for each region of operation. The SPICE and analytical results for the output voltage waveform and propagation delay match very closely.

Resonant switching power source apparatus

Abstract: A resonant switching power source apparatus has a first switching element and second switching element being connected in series between output terminals of a DC power source and are alternately turned on and off; a series resonant circuit having a primary winding of a transformer and a current resonance capacitor and connected in parallel with the second switching element; a controller to control the first and second switching elements; a rectifying/smoothing circuit to rectify and smooth a voltage, which is generated on a secondary winding of the transformer during an ON period of the second switching element, and output the rectified-smoothed voltage; a current detector to detect a current passing through the series resonant circuit; and an overcurrent protector to turn off the first and second switching elements for a predetermined period so that excitation energy of the transformer is reset, if the current detector detects a predetermined current value.

Position tracking of passive resonance-based transponders

Abstract: A system for position tracking includes one or more field generators, which are arranged to generate one or more respective position-varying magnetic fields. A transponder includes a resonant circuit having a resonance frequency and including a field-responsive element, which is operative to vary the resonance frequency responsively to the one or more magnetic fields. A position tracker is arranged to remotely sense the resonance frequency of the resonant circuit and to determine a position of the transponder responsively to the sensed resonance frequency.

The Current and Voltage Phase Shift Regulation in Resonant Converters With Integration Control

Abstract: This letter presents an application of the phase controller which allows a regulation of current and voltage phase shift in resonant circuit with nonperiodic voltage waveform. The phase controller has been implemented using the voltage-controlled oscillator generator operating with double resonant frequency, creation of additional auxiliary voltage signal, and phase-locked loop. The results of computer simulations and laboratory experiments show that the proposed phase controller allows a simple and efficient phase shift regulation for all known systems of integration control with a continuous and discontinuous resonant current flow

Structural vibration control via R-L shunted active fiber composites

Abstract: This article presents a successful extension of passive R-L shunt damping to piezoelectric ceramic elements working in direct 3-3 mode and a performance comparison to elements working in indirect 3-1 mode. A new circuit topology is implemented to synthesize the very large inductances required by the low inherent piezoelectric device capacitance at relatively low frequencies. This allows for efficient tuning of the R-L circuit to the structure resonance frequency to be damped. The vibration suppression performance of monolithic piezoelectric ceramic actuators and active fiber composites is compared in this study. For this purpose, different actuators are bonded on aluminum cantilever plates. An integrated FE model is implemented for the prediction of structure resonance frequencies, optimum values for electric components, and the resulting vibration suppression performance. The passive structure, bonded active patch, and shunted electrical network are analyzed within the same FE model. Active fiber composite patches working in the direct 3-3 mode show equivalent specific damping performance compared to conventional monolithic 3-1 actuated patches. Issues related to the sensitivity of R-L shunts to variations in environmental and operational conditions are discussed in this study. In short, monolithic actuators operating on the 3-1 piezoelectric effect seem to be the best for use in R-L shunting.

Design of a Very High Frequency dc-dc Boost Converter

Abstract: Passive component volume is a perennial concern in power conversion. With new circuit architectures operating at extreme high frequencies it becomes possible to miniaturize the passive components needed for a power converter, and to achieve dramatic improvements in converter transient performance. This thesis focuses on the development of a Very High Frequency (VHF, 30 300 MHz) dc-dc boost converter using a MOSFET fabricated from a typical power process. Modeling and design studies reveal the possibility of building VHF dc-dc converters operable over the full automotive input voltage range (8 18 V) with transistors in a 50 V power process, through use of newly-developed resonant circuit topologies designed to minimize transistor voltage stress. Based on this, a study of the design of automotive boost converters was undertaken (e.g., for LED headlamp drivers at output voltages in the range of 22 33 V.) Two VHF boost converter prototypes using a Φ2 resonant boost topology were developed. The first design used an off the shelf RF power MOSFET, while the second uses a MOSFET fabricated in a BCD process with no special modifications. Soft switching and soft gating of the devices are employed to achieve efficient operation at a switching frequencies of 75 MHz in the first case and 50 MHz in the latter. In the 75 MHz case, efficiency ranges to 82%. The 50 MHz converter, has efficiencies in the high 70% range. Of note is low energy storage requirement of this topology. In the case of the 50 MHz converter, in particular, the largest inductor is 56 nH. Finally, closed-loop control is implemented and an evaluation of the transient characteristics reveals excellent performance. Thesis Supervisor: David J. Perreault Title: Associate Professor of Electrical Engineering

Resonant circuit, filter circuit, and antenna device

Abstract: In resonant elements 102 to 105 constituting a resonant circuit, an uncontrolled cross coupling which exists between two resonant elements is controlled by using a coupling element 106 which is newly arranged between the resonant elements, whereby it is possible to create a state where two resonant elements are not coupled with each other or a state where the amount of the coupling is reduced, which states are difficult to be realized on a plane. As a result, it is possible to improve characteristics of a planar filter.

Inductive power transfer system pick-up circuit

Abstract: An Inductively Coupled Power Transfer (ICPT, or IPT) pick-up circuit is provided which includes an inductive element L2 provided between a resonant circuit and a rectifier means. A DC inductor is not required. The inductive element L2 is chosen to have substantially the same inductance as that of the pick-up coil L1, reducing or eliminating the reactive component of the reflected impedance.