Efficient thermal management in high-power electronics cooling can be achieved using phase-change heat transfer devices, such as vapor chambers. Traditional chambers use wicks to transport condensate for efficient exchange and prevent "dry-out" of the evaporator. However, present significant design challenges arising out large pressure drops across wicking material, which slows down rates increases chances dry-out. Thicker add overall resistance, while deterring development thinner devices...

This paper presents a multi-resonant-frequency (MRF) filter for high-frequency inverter (HFI) used in electrosurgery. The fundamental (sinusoidal) output frequency of the HFI is 390 kHz and same as switching HFI. MRF designed to extract tri-state bipolar waveform, generated by operating with phase-shift control. structure operation are outlined. An experimental 300 W GaN-FET-based prototype developed validate feasibility proposed under closed-loop

To power electrosurgery, a very-high-frequency AC inverter (VHFI) is required. In this paper, full-bridge based VHFI proposed to enable electrosurgery. Its high-frequency output generating mechanism and the high order filter design are explained. check feasibility of VHFI, 300 W Gallium Nitride High Electron Mobility Transistors (GaN HEMT) experimental setup with 390 kHz frequency, has been designed implemented. Experimental efficiency total harmonic distortion (THD) results graphed for pure...

Well-selected power with accurate delivery is of importance in electrosurgery to generate proper temperature at the cutting site, and thus, reduce undesired collateral tissue damages. Conventional generator (ESG) targets tracking a preset power, manually set by surgeons per their experience before surgery, high delivery. It possible that this fixed setting not optimal point and, increases possibility added-collateral biomedical damage. To eliminate potential negative impact ill-suited...

A hybrid vapor chamber (wick-lined evaporator and wickless condenser) is fabricated tested on a custom-made power electronic setup to demonstrate its efficacy in cooling power-semiconductor devices. The method omits some metal-wick structures from the interior of replaces them with wickless, surface-energy patterned planar components. heat sources are two N-Channel Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) TO-247-3 packaging, which connected parallel achieve higher current...

In this paper, starting with a brief background on electrosurgery, we demonstrate that power electronics supported by feedback control is the verge of making major impact advancement medical discipline. We detail recent reported advances in closed-loop precision using high-frequency electronics, showing pathway towards reducing collateral damage electrosurgery to enable better surgical outcomes. vivo extension authors' previous dead tissue, electrosurgical cutting mode closed loop results...

Peak current mode (PCM) control exhibits superiority over voltage-mode-control (VMC) in aspect of overcurrent protection, magnetic saturation elimination and fast transient response, etc., thus PCM-based scheme finds wide application numerous areas. In this paper, operation modes, modeling, analysis, design for both are presented differential Ćuk inverter (DMCI). The comparison between two schemes reveals that has better stability is easier to than VMC-based control. Next, Matlab/Simulink...

This paper investigates two ways of output-power computation, namely, sparse- and multi-sampling-based methods, to overcome sampling speed limitation arcing nonlinearity for electrosurgery. Moreover, an impedance-based power adaptation strategy is explored reduced collateral tissue damage.The efficacy the proposed computation are experimentally investigated on a gallium-nitride (GaN)-based high-frequency inverter prototype that allows electrosurgery with 390 kHz output frequency.The...

In 1881, Morton found that a high-frequency (100-kHz) current could pass through the human body without inducing pain, spasm, or burn <xref ref-type="bibr" rid="ref1" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">[1]</xref> . This work was followed in 1891 by d'Arsonval who noted similar observations at frequency of 10 kHz and directly influenced temperature, oxygen absorption, carbon dioxide elimination, increasing each as passed rid="ref2"...

The arcing-involved pulsating coagulation mode with both active and blank periods is essential for modern electrosurgery. This paper begins a comprehensive introduction to such mode, followed by its implementation challenges. Then, an industrial-scale low-speed microcontroller unit (MCU), TMS320F28379D, utilized exemplify the proposed output sampling data-transferring strategy on gallium nitride (GaN)-based high-frequency inverter that enables interweaved periods. prototype fills period 390...

Vapor chambers (VC)s are passive heat spreaders that dissipate localized by distributing their working liquid's latent in efficient ways, and turn, promoting device performance. Beside the fluid its amount sealed a VC, thermal performance of these devices relies on three phenomena; evaporation, condensation, circulation fluid. Evaporation is influenced core structure, such as wick or porous medium micro/nano arrangement, thickness, porosity, permeability, while other hand, physicochemical...