RLC circuit

About: RLC circuit is a research topic. Over the lifetime, 14490 publications have been published within this topic receiving 142697 citations.

Unbalanced Three-Phase $LLC$ Resonant Converters: Analysis and Trigonometric Current Balancing

Abstract: Three-phase $LLC$ resonant converters can handle very high power levels beyond the capabilities of half-bridge and full-bridge $LLC$ topologies. Among other characteristics, three-phase $LLC$ structures reduce output current ripple (small output filter), enable parallel power processing (low peak current), and provide good thermal distribution. However, all these key advantages can be severely compromised due to passive components tolerances, leading to undesired current balance issues in three-phase $LLC$ resonant converters. Tolerances in resonant tank passive components are inevitable and lead to unequal peak currents between phases, uneven temperature distribution, and large output current ripple. This paper investigates the imbalances in three-phase $LLC$ converters and proposes a novel trigonometric current balancing (TCB) technique using phasor analysis. In this strategy, the required input voltage phase angles are calculated to achieve balanced phase currents, even under severe unbalanced conditions. In some cases, the output filter current ripple is reduced to less than half. The methodology is verified with a 3-kW experimental prototype, which validates the analytical framework and effectiveness of TCB.

Double-clamped ZVS buck-boost power converter

Abstract: A transformer-coupled buck-boost DC-DC power converter is disclosed An active clamp circuit is provided to form a resonant circuit with the transformer to control the slew rate of the secondary current and allow the secondary switch to be turned ON at conditions of zero voltage and relatively low current The characteristic resonant period of the active clamp transformer circuit may be less than the minimum converter operating period A winding of the transformer is shunted during a clamp phase to retain energy in the transformer ZVS phases are provided to reduce switching losses when switches in the converter are turned ON An energy-storage phase may be varied to control the amount of energy stored per operating cycle An input-storage phase may transfer energy to the clamp capacitor during a series of converter operating cycles and transfer said energy to the secondary during different converter operating cycles

Evaluation of High-Frequency Circuit Models for Horizontal and Vertical Grounding Electrodes

Abstract: Circuit models of horizontal and vertical grounding electrodes are traditionally used in high-frequency (HF) analysis, although underlying approximations limit their accuracy in some low-frequency ranges. Recently, a number of new circuit models have been introduced, but the improvement of the accuracy at HF has not been systematically evaluated. In this paper, we show that new circuit models can be directly derived from method of moments solutions of the integral forms of Maxwell equations by introducing different assumptions. This approach helps to categorize different models into only a few categories based on underlying approximations. To determine the applicable range, we analyze the error for impedance to ground computed by different circuit models in comparison to that calculated by a rigorous full-wave model over wide ranges of parameters, such as electrode length, soil resistivity, and frequency. This paper: 1) provides a parametric analysis that enables the estimation of the applicability of the particular circuit model for application to a practical case based on its accuracy; 2) presents a unified systematic approach to derive circuit models with different capabilities; and 3) reveals that the modeling of the mutual coupling between different parts of the grounding electrode is the key factor for radically improving the accuracy of circuit models at HF.

23.5 An energy pile-up resonance circuit extracting maximum 422% energy from piezoelectric material in a dual-source energy-harvesting interface

Abstract: Energy harvesting is one of the key technologies used to realize self-sustaining systems such as wireless sensor networks and health-care devices. Much research on circuit design has been conducted to extract as much energy as possible from transducers, such as the thermoelectric generator (TEG) and the piezoelectric transducer (PZT). Specifically, the energy in a PZT could be extracted more efficiently by utilizing resonance as [1] and [2] demonstrated. However, the maximum output voltage swing in those techniques are limited to twice of the original swing of the PZT, and thus, had a limited energy extraction capability in spite of more energy being available from the PZT. In [3], on the other hand, the large energy is obtained with higher voltage swing, but is limited up to 247% because the load energy is used to increase the output voltage swing of PZT. To obtain far more power from PZT, we propose an alternative resonance technique through which the PZT output swing can be boosted as high as CMOS devices can sustain. This technique is applied to a dual-energy-sourced (PZT and TEG) energy-harvesting interface (EHI) as a battery charger.

Experimental study and mathematical modelling of a new of vibro-impact moling device

Abstract: In this paper experimental study and mathematical modelling of newly designed vibro-impact moling rig are presented. The design is based on electro-mechanical interactions of a conductor with an oscillating magnetic field. The rig consists of a metal bar placed within a solenoid which is connected to an RLC circuit, and an obstacle block positioned nearby. Both the solenoid and the block are attached to a base board. Externally supplied alternating voltage causes the bar to oscillate and hit the block resulting in the forward motion of the base board mimicking a mole penetration through the soil. By varying the excitation voltage and the capacitance in the circuit, a variety of system responses can be obtained. In the paper the rig design and experimental procedure are explained in detail, and the mathematical modelling of the rig is described. Then the obtained coupled electro-mechanical equations of motion are integrated numerically, and a comparison between experimental results and numerical predictions is presented.