Search

Your search keyword '"Moon, Seok-Hwan"' showing total 97 results
Start Over Author "Moon, Seok-Hwan"
97 results on '"Moon, Seok-Hwan"'

2. Process window of simultaneous transfer and bonding materials using laser‐assisted bonding for mini‐ and micro‐LED display panel packaging.

Author

Eom, Yong‐Sung, Choi, Gwang‐Mun, Jang, Ki‐Seok, Joo, Jiho, Lee, Chan‐mi, Oh, Jin‐Hyuk, Moon, Seok‐Hwan, and Choi, Kwang‐Seong

Subjects
PACKAGING, SOLDER & soldering, SEMICONDUCTOR lasers, DIODES, VISCOSITY, POTS, LASERS
Abstract

A simultaneous transfer and bonding (SITRAB) process using areal laser irradiation is introduced for high‐yield and cost‐effective production of mini‐ or micro‐light‐emitting diode (LED) display panels. SITRAB materials are special epoxy‐based solvent‐free pastes. Three types of pot life are studied to obtain a convenient SITRAB process: Room temperature pot life (RPL), stage pot life (SPL), and laser pot life (LPL). In this study, the RPL was found to be 1.2 times the starting viscosity at 25°C, and the SPL was defined as the time the solder can be wetted by the SITRAB paste at given stage temperatures of 80°C, 90°C, and 100°C. The LPL, on the other hand, was referred to as the number of areal laser irradiations for the tiling process for red, green, and blue LEDs at the given stage temperatures. The process windows of SPL and LPL were identified based on their critical time and conversion requirements for good solder wetting. The measured RPL and SPL at the stage temperature of 80°C were 6 days and 8 h, respectively, and the LPL was more than six at these stage temperatures. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

10. Effective algorithms of a power converter for tidal current power generation system

Author

Moon, Seok-Hwan, Park, Byung-Gun, Kim, Ji-Won, and Kim, Jang-Mok

Abstract

This study investigates design procedures and experimental results of power converters for the tidal current power generation system installed at Jin-Do in Korea. The designed power converters consist of a grid-connected converter and a power converter to control the permanent magnet synchronous generator. Many theoretical control algorithms are required to design the power converter for a tidal current power generation system. In this study, the effective algorithm of power converters for a tidal current generation on the phase lock loop algorithm of the grid-connected converter and maximum power point tracking algorithm of generator-side converter was investigated. For the feasibility study of the commercial tidal current power generation system, the down-scaled 20-kW tidal generation system has been installed and empirically evaluated.

Published
2024
Full Text
View/download PDF

11. Maximum Power-Point Tracking Control Using Perturb and Observe Algorithm for Tidal Current Generation System

Author

Moon, Seok-Hwan, Park, Byung-Gun, Kim, Ji-Won, and Kim, Jang-Mok

Abstract

Because wind turbines and tidal current generation rely on irregular wind or tidal speed, maximum power-point tracking (MPPT) control is required in order to generate maximum turbine power. The most common turbine generation is obtained by employing the MPPT scheme using the tip speed ratio (TSR). However, this scheme has a disadvantage in that it relies on the characteristics of tidal current turbines, and it requires expensive tidal current speed-measurement equipment. The tidal current speed measurement is also affected by the installed location and distance to the equipment. To avoid these disadvantages, this paper proposes the maximum power control scheme using perturb and observe (P&O) for tidal current generation systems. The proposed P&O MPPT scheme can generate maximum power regardless of the characteristics of the turbine and the information about the tidal current speed. The reliability and suitability of the proposed scheme are proven using simulation and experiment results at the tidal current generation laboratory in Jin-do, South Korea.

Published
2024
Full Text
View/download PDF

20. Collective laser‐assisted bonding process for 3D TSV integration with NCP

Author

Hyun-Cheol Bae, Keon-Soo Jang, Yong-Sung Eom, Wagno Alves Braganca Junior, Moon Seok Hwan, and Choi Kwang-Seong

Subjects
Bonding process, Materials science, General Computer Science, business.industry, lcsh:Electronics, laser‐assisted bonding, lcsh:TK7800-8360, TSV, Laser assisted, Electronic, Optical and Magnetic Materials, lcsh:Telecommunication, lcsh:TK5101-6720, NCP, Optoelectronics, Electrical and Electronic Engineering, business, 3D integration, collective bonding
Abstract

Laser‐assisted bonding (LAB) is an advanced technology in which a homogenized laser beam is selectively applied to a chip. Previous researches have demonstrated the feasibility of using a single‐tier LAB process for 3D through‐silicon via (TSV) integration with nonconductive paste (NCP), where each TSV die is bonded one at a time. A collective LAB process, where several TSV dies can be stacked simultaneously, is developed to improve the productivity while maintaining the reliability of the solder joints. A single‐tier LAB process for 3D TSV integration with NCP is introduced for two different values of laser power, namely 100 W and 150 W. For the 100 W case, a maximum of three dies can be collectively stacked, whereas for the 150 W case, a total of six tiers can be simultaneously bonded. For the 100 W case, the intermetallic compound microstructure is a typical Cu‐Sn phase system, whereas for the 150 W case, it is asymmetrical owing to a thermogradient across the solder joint. The collective LAB process can be realized through proper design of the bonding parameters such as laser power, time, and number of stacked dies.

Published
2019

26. Development of Digital Signage Modules composed of Mini-LEDs using Laser-Assisted Bonding (LAB) Technology

Author

Choi, Kwang-Seong, primary, Joo, Jiho, additional, Jang, Ki-seok, additional, Eom, Yong-Sung, additional, Choi, Gwang-Mun, additional, Yun, Ho-Gyeong, additional, Moon, Seok Hwan, additional, Kim, Jong-Sun, additional, Oh, Mingyun, additional, Choi, Ji-Hoon, additional, Choi, Ji-Woong, additional, Cho, Sung-Yun, additional, Choi, Shin, additional, Park, Sang-Hong, additional, Kim, Gi Cheol, additional, Kim, Sang-Ki, additional, Kim, Jin Sung, additional, and Yoo, Sehoon, additional

Published
2020
Full Text
View/download PDF

34. Enhanced Performance of Laser-Assisted Bonding with Compression (LABC) Compared with Thermal Compression Bonding (TCB) Technology

Author

Choi, Kwang-Seong, primary, Eom, Yong-Sung, additional, Moon, Seok Hwan, additional, Joo, Jiho, additional, Jeong, leeseul, additional, Lee, Kwangjoo, additional, Kim, Jung Hak, additional, Kim, Ju hyeon, additional, Yoon, Gil-Sang, additional, Lee, Kwang-Hee, additional, Lee, Chul-Hee, additional, Ahn, Geun-Sik, additional, and Shim, Moo-Sup, additional

Published
2019
Full Text
View/download PDF

44. Adaptive PLL method using recursive least square algorithm

Author

Moon Seok-Hwan, Park Byung-Gun, and Kim Ji-Won

Subjects
Least mean square algorithm, Engineering, Offset (computer science), business.industry, Hardware_PERFORMANCEANDRELIABILITY, Time–frequency analysis, Line current, Phase-locked loop, Amplitude, Control theory, Hardware_INTEGRATEDCIRCUITS, business, Reference frame, Voltage
Abstract

The implementation of conventional synchronous reference frame PLL(SRF-PLL) is simple and estimation performance of the phase angle is superior under balanced utility voltage. However, conventional SRF-PLL degrade its performance under unbalanced utility voltage. The proposed DIF-PLL to overcome this problem only compensate for amplitude variation of the phase voltage and estimation performance of the phase angle degrade under other unblanced utility voltage. This paper proposes SRF-PLL using recursive least square method(RLSM), which detect the phase angle by compensating in real time for the generated angle, amplitude and offset of the phase voltage by unbalanced utility voltage. The proposed method is verified through the simulation and experiments.

Published
2015

45. On-line compensation of magnetic position sensor using recursive least square method

Author

Moon Seok-Hwan, Kim Ji-Won, and Park Byung-Gun

Subjects
Engineering, Stator, business.industry, Linear motor, Magnetic flux, law.invention, Quantitative Biology::Subcellular Processes, Magnetic core, law, Control theory, Magnet, Waveform, Hall effect sensor, business, Position sensor
Abstract

This paper presents the error correction method for magnetic position sensor using recursive least square method (RLSM) with forgetting factor. The magnetic sensor modules are proposed for linear position detection of the linear motor which has tooth shape stator. The modules are consists of permanent magnet, iron core and linear hall sensor and generates sine and cosine waveforms according to the movement of the mover of the linear motor. From the output of magnetic sensor modules, the position of the linear motor can be detected using arc-tan function. But the variation of the air gap between magnetic sensor modules and the linear motor stators, and some errors in manufacturing process can cause the variation in offset, phase and amplitude of the generated waveforms when the linear motor moves. These variations in sine and cosine waveforms are changed according to the current linear motor position, and it is very difficult to compensate the errors using constant value. In this paper, the generated sine and cosine waveforms from the magnetic sensor modules are compensated in real time using the RLSM with forgetting factor. And the speed observer is introduced to reduce the effect of uncompensated harmonic component. The proposed methods are verified by some simulations and experiments.

Published
2015

Catalog

Books, media, physical & digital resources
See catalog results