About Me

Current Position

Massachusetts Institute of Technology, Cambridge, MA
Postdoctoral Associate, Electrical Engineering and Computer Science06/2016–Present
 
 

Education

Massachusetts Institute of Technology, Cambridge, MA
Ph.D., Electrical Engineering and Computer Science 06/2012–06/2016 
– Thesis: High Frequency Power Conversion Architecture for Grid Interface
– Advisor: Prof. David J. Perreault
– Committee: Prof. Charles R. Sullivan, Prof. Anantha P. Chandrakasan, and Prof. Tomas Palacios

M.S., Electrical Engineering and Computer Science 08/2010–06/2012 
– Thesis: A Merged Two-Stage Power Conversion Architecture with Switched Capacitor Circuit for an LED Driver Module
– Advisor: Prof. David J. Perreault

Seoul National University, Seoul, South Korea
B.S., summa cum laude, Electrical Engineering and Computer Science 03/2004–08/2010 
 

Research Experience

Postdoctoral Associate 06/2016–Present 
Power Electronics Laboratory, MIT, Cambridge, MA
– Developed an efficient and miniaturized bi-directional dc-dc converter at 1kW power level for electric vehicle applications.
– Mentored undergraduate and graduate students for research.

Graduate Research Assistant 08/2010–06/2016
Power Electronics Laboratory, MIT, Cambridge, MA
– Designed a miniaturized isolated ac-dc converter: 50W/100W power level, high efficiency, high power factor, five times smaller than the state-of-the-art converters, high switching frequency at 1–10 MHz with zero-voltage-switching operation.
– Developed a miniaturized LED driver: 35W power level, high efficiency, high power factor, five times smaller than the conventional designs.
– Designed and tested a EMI/EMC filter for ac-dc converters (FCC Part 15/CISPR 22 Conducted Emissions Limits, Class B).
– Proposed and patented a new power factor correction architecture (stacked structure) applicable to many grid interfacing applications.
– Developed a new isolated dc-dc bus converter: high switching frequency operation at 1–5 MHz, simple control circuitry, and high efficiency with zero-voltage-switching operation.
– Investigated the low permeability magnetic core materials (NiZn and Powdered Iron) at high frequency (1–10MHz) for inductor and transformer design.

Undergraduate Research Assistant 12/2009–08/2010
Integrated System Design Laboratory, Seoul National University, Seoul, South Korea
– Designed all-digital clock data recovery circuit, analyzed jitter characteristic, and improved data acquisition range.

Research Engineer 01/2007–08/2009
Silicon Motion (Future Communication IC), Sungnam, South Korea
– Fabricated multiple RF tuner ICs for mobile TV (DMB, DVB, and ATSC) applications.
– Designed the chip-to-chip digital protocol (I2C and SPI) circuit with 90nm, 130nm, 180nm CMOS process.
– Tested reliability of fabricated ICs and measured noise performance of LNA, Mixer, and PLL circuits.

Internship 06/2006 — 08/2006
Lucent Technologies, South Korea
– Analyzed demand and hardware system configuration of internet protocol television (IPTV).

Summit Conference Scholar 07/2005
Lucent Global Science Scholar Summit, Bell Laboratory, Murray Hill, NJ
– Proposed a method to analyze crystalline structures using laser. 
 

Honors and Awards

Will Portnoy First Prize Award, IEEE Industry Applications Society, 2016
Samsung Scholarship for Doctoral Students, Samsung Scholarship, 2010–2015
Presidential Science Scholarship, Government of South Korea, 2004–2010
Lucent Global Science Scholarship, Lucent Technologies Foundation, 2005
Dean’s List Fellowship, College of Engineering, Seoul National University, 2004  
 

Participation in Sponsored Research Contracts

Research Grant, Bosch, PI: Prof. David J. Perreault at MIT 12/2016 
– Awarded $230k for 21 months to research on “Investigation of High Frequency Miniaturized dc-dc Conversion for Automotive EV/HEV Applications.”
– Participated in writing the proposals and will investigate and design prototype converters.
Research Grant, Fairchild Semiconductors PI: Prof. David J. Perreault at MIT 09/2015 
– Awarded $200k for 18 months to research on “High Power Density, High Frequency Power Factor Correction Converter for Universal Input Grid Interface.”
– Participated in writing the proposals and advised graduate students.

 

Teaching Experience

Co-Lecturer, 6.334 Power electronics (graduate course) Spring 2017, MIT, Cambridge, MA
Teaching Assistant, 6.334 Power electronics (graduate course) Spring 2014, MIT, Cambridge, MA
– Graded exams and homework assignments and opened regular office hours.
– Gave lectures in regular classes and discussion sessions.