Expert Details
Power Electronics and Electric Drives, EMI/EMC Filter, Optoelectronics, Amplifiers for Sensors
ID: 724418
California, USA
Expert has strong academic background in DC-DC converters; his master degree focused on DC-DC converters. In addition, he has designed power supplies for Military and Aerospace applications such as: Fast Response Boost Converter (28v input to 100V-200V output) for laser driver, 28v Isolated Flyback Converter for Boeing's applications, and others for electronic circuits.
He has strong experiences in feedback control and electronic hardware realizations. He worked with Phase Lock Loop (PLL), DC and BLDC motor controls which related to PI, PID, Phase Boost, Lead/Lag compensators. Experienced with Body plot, Root locus, Nyquist Pot, and Complex plan analysis.
Expert is experienced in switch circuits such as DC-DC converters such as Buck, Boost, Buck-Boost, Flyback, Cuk, PFC...and Inverters.
He designed electronics to support Laser Above Ground Level (LAGL)such as: Laser pule sensor using APD and PIN diodes. Designed amplifiers to detect and amplifier low and high power laser return pulses. Due to wide dynamic power range, the amplifiers potentially become saturated this may cause miscalculations and problems. To overcome this issue, he designed an amplifier using a technique called Zero-Crossing-Point to minimize the effects of amplifier saturation. In sensor applications, sensitivity is the main factor to determine how far/long a device can detect and the sensitivity is directly proportional to the detector bandwidth. Conventional 20ns pulsewidth/50MHz bandwidth detectors can detect 50m - 1Km objects at resolution of 2m - 10m. To maximize sensitivity, He has developed a detector that increase S/N ratio by using technique which allow to banpass filter at higher frequencies to increase detectable distance up to 3Km at resolution of 0.5m. This is a great advantage for applications which involved with range finders, Level sensors and other sensor related.
Expert understands magnetic sensor applications, such as for: air compressors, Liquid Cooling Systems, piston position and motor speeds and positions (Resultver).
Expert is experienced with Avalanch Photo Diodes, PIN diodes and electronic related to detecting small optical power such as: high bandwidth amplifier AD8009 from Analog Device and High switch PWM from Linear Tech.
Education
| Year | Degree | Subject | Institution |
|---|---|---|---|
| Year: 2005 | Degree: MS | Subject: Electrical Engineering - Power Electronics & Electric Drives | Institution: University of Minnesota |
| Year: 2002 | Degree: BS | Subject: Electrical Engineering - Analog/Digital Curruit Design | Institution: University of Minnesota |
Work History
| Years | Employer | Title | Department |
|---|---|---|---|
| Years: 2007 to Present | Employer: Undisclosed | Title: Sr. Design Engineer | Department: Central Engineering |
Responsibilities:Chair of the electronic team at the 2008 Piezolectronic Symposium.Worked with R&D group on BLDC motor control. Designed isolated flyback power supply, EMI/EMC filter for 3-phase and 28V DC phase power supplies. Performed analog circuit analysis and simulation to support concept design. Familiar with Boeing power and EMI/EMC SPECs. Researched and Developed high temperature (200C), Voltage (270Vdc) and current (100Adc) SiC Power Control. Researched and Developed high temperature (250C) Power Electronics and Reluctant Motor Drives. Developed a patentable circuit to drive high speed Piezoelectric applications |
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| Years | Employer | Title | Department |
| Years: 2006 to 2007 | Employer: Honeywell | Title: Sr. Analog Design Engineer | Department: Strategic Sensors |
Responsibilities:Part of R&D group to define and design a most advanced laser sensor implementing relativity theorem to measure rotational motions. Debugged and redesigned part of emulator's circuit to test Gyroscopes. Created and modified power supply schematics. Debugged and troubleshoot firmware of Emulator to simulate optical sensors. Designed and developed analog circuits to support optical applications such as: Rotation Sensors and Gyroscopes. Responsible for component quality analysis to meeting Military Requirements and Electronic Critical Design Review (ECDR). Experienced with the lasted Fiber Optic Gyroscope (FOG) technology and implemented it in angular acceleration measurement and missile control. |
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| Years | Employer | Title | Department |
| Years: 2003 to 2006 | Employer: Goodrich | Title: Electrical Design Engineer | Department: Homeland Security |
Responsibilities:Worked on Analog/Digital circuits, experienced with advance laser technology. Involved in creating high level specification for Laser Perimeter Awareness System, writing specifications 3GHz broadband APD-analog detector and performing high level analysis to determine what kind of detector is suitable for 25 cm range resolution.Designed and developed a laser pulse detector called Multiple Reflected Pulse Detector (MRPD). The MRPD has bandwidth of 500MHz, output pulsewidth of 3ns, multiple target resolution as low as 0.45m and input dynamic range is greater 90dB. Experienced with AC/DC Analysis, Noise Figure, Signal to Noise Ratio, Input Dynamic Range, Gain Compression and Stability (Body Plots, Root Locus, Nyquist Plots, and Gain Margin). Designed filters to protect electronics from EMI noises. Experienced with Military environmental standards. Researched and designed RF/Microwave circuits for APD-analog detector and worked with consultants to get design support. Researched for different kinds of detectors and created a Trade-Off Matrix as requested by manager. Determined it was needed to use a 3GSPS ADC to sample the analog output of the detector. Identified the matching networks for input/output of the ADC. Experienced with Impedance Matching Networks using Smith Chart/ quantitative calculations, Striplines/Microstriplines and Power Optimization. Identified problematic laser on/off under the influence of temperature variation and came up with a solution to fix the problem. Tested, debugged, documented and developed the altimeter prototype of a Laser Above Ground Level Experienced with the analog module and Avalanche photo diodes (Thermal, short, and dark noises). Analyzed data for compensating the system errors Designed power DC-DC converter to control the TEC cooler Researched and applied Direct Torque Control (DTC) to control Induction Motors. Designed variable voltage control current sources for Thermal Electric cooling applications. Designed circuits for optical detectors for military application (EMC/EMI military standard requirements: Mil-std-641E, Mil-std-704F) Worked with mechanical engineers to create a trade study for selecting motors. Analyzed the advantages and disadvantages between Stepper and Brushless DC motors by comparing: Torques, power consumptions and currents in transient/steady states. Designed 28V @ 600W and 1500W power supplies that meet Mil-std-641E and 704F. |
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| Years | Employer | Title | Department |
| Years: 2000 to 2002 | Employer: Honeywell | Title: Student Intern | Department: Environmental Controls |
Responsibilities:Compared and analyzed electronic schematics for existing and cost reduced designs to verify.Components and functionality. Suggested corrections for errors discovered. Visually inspected in warranty return products, focusing on cracked SMT capacitors. Located and order components for rush factory support. Performed systems integration testing (SIT) for NT based building software. Rewrote software interface specification to reduce engineering time spent looking up critical design parameters. |
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Career Accomplishments
| Professional Appointments |
|---|
| Appointed to be the chair of the 2008 Power Electronics and Electric Drives Symposium |
| Publications and Patents Summary |
|---|
| Designed and developed a laser pulse detector called Multiple Reflected Pulse Detector (MRPD) implementing Zero – Crossing- Point and Pulsewidth Limiter Concepts. The MRPD has bandwidth of 500MHz, output pulsewidth of 3ns, multiple target resolution as low as 0.45m and input dynamic range is greater 90dB. Experienced with AC/DC Analysis, Noise Figure, Signal to Noise Ratio, Input Dynamic Range, Gain Compression and Stability (Body Plots, Root Locus, Nyquist Plots, and Gain Margin). This design was file for a U.S. patent. Published a paper on induction motor control using Direct Torque Control (DTC) method Developed a electric drive circuit for high speed Piezoelectronic applications. (patentable) |
Additional Experience
| Training / Seminars |
|---|
| -Chair of the electronic team at the 2008 Piezolectronic Symposium -He has worked with students as a tutor to provide mathematical skills and approaches. He has presented many concepts to overcome problems such as: Wide Input Dynamic Range of Laser Pulse Detectors (detector saturation), Gyroscope PLL Unlock problems, and Low Resolution Range Finder. |
| Vendor Selection |
|---|
| He has worked with vendors/suppliers such as: 1. Linear Tech: 7201 W. 78th, suite 210, Bloomington MN 55439-0813 (select components to meet Military and Aerospace application requirements) 2. Vanguard Electronics Company Transforms and Inductors Design and Manufacture 7412 Prince Dr. Huntington Beach, CA 92647 |
| Marketing Experience |
|---|
| He has been trained and experienced in Power Electronics (DC-DC converters) and Electric Drives (Induction, BLDC and DC motor control using Space Vector Control, and Directorque Control, dq Analysis). -He has great experience in design/design analysis electronics for optical sensors, Transimpedance amplifier, amplifiers for small optical signals, Laser pulse detectors. - He has great experience in simulations and modelings to support concept design verifications. -EMI fitters design experience with Military and Boeing specifications. |
| Other Relevant Experience |
|---|
| Testing and review. Along with presentations. |
Language Skills
| Language | Proficiency |
|---|---|
| Vietnamese | He had 22 year experience using this language. |
Fields of Expertise
circuit design, control system, DC-to-DC converter, electric-power converter, power electronics, electric feedback, feedback control system, electric switch, level sensor, liquid level sensor, optoelectronics science, sensor, sensor technology, magnetic sensor, optoelectronic circuit, photodetector circuit, internal security (military), emergency shutdown system, flame sensor, sensor noise, patient monitoring sensor, vibration sensor, multifunction sensor, aerospace electronics science, farm equipment sensor, dc link converter, speed sensor, switch contact, sun sensor, electric contact design, near-infrared sensor, smart sensor, velocity sensor, analog output, analog switch, Butterworth filter, road condition sensor, force sensor, position sensor, military sensor, color sensor, space electronics science, military electronics science, control-system direct-current motor, thermal sensor, acoustic sensor, control system resolution, electromechanical control system, engineering control computer system, control system analysis, control system design, embedded sensor, electronics, control loop dynamic analysis, control system performance evaluation, computer-based electronic system simulation, torque sensor, infrared sensor, temperature sensor, alternating-current to alternating-current conversion, control-system modeling, electric-power conversion, direct-power generator, alternating-current transformer, solid-state electronics science, flow sensor, electric conductor, pressure sensor, electric field, multicomponent sensor, switching system, solid-state switch, security system, proximity sensor, picosecond optoelectronics science, optical sensor, moisture sensor, integrated optoelectronics science, gas sensor, electric circuit, control loop, control electronics science, audio electronics science, applied electronics science