• Journal of the Institute of Electronics Engineers of Korea TE
• /
• v.42 no.3
• /
• pp.39-44
• /
• 2005

In this paper, we use the 5-ary frequency shift keying method for robust powerline communication. To transmit the data by the 3-ary carrires among 5-ary carrirers and three carriers are 115kHz, 120kHz and 125kHz. Each time of three carrires is 0.33ms and total transmitting time duration from zero crossing point has 1ms. We use the dummy carriers which are 50kHz and 350kHz for monitoring the powerline channel state, dummy signal duration is received during 1ms. Experimentation result is shown that the implemented PLC transceiver has better than chirp transceiver at the capacitive load testing in spite of low transmission power.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.27 no.3
• /
• pp.424-431
• /
• 2003

The spacer grid is one of the main structural components in the fuel assembly, which supports the fuel rods and maintains coolable geometry from an external load. A vibration test and a finite element analysis using ABAQUS on a dummy fuel rod continuously supported by Optimized H type(OHT) and New Doublet (ND) spacer grids arc performed to obtain the vibration characteristics such as natural frequencies and mode shapes an(1 to verify a finite element model. The results from the test and the finite element analysis are compared by modal assurance criteria (MAC) values. It is resulted that MACs for the first, the third and the fifth mode shapes are relatively good as compared with those of the second an(1 fourth ones. The natural frequency differences between two methods as well as the mode comparison results for the rod with OHT spacer grid are better than those with ND spacer grid. It is judged that the FE model for the ND spacer grid spring should be modified to consider the long contact length which actually happen when the spring supports the rod.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.12 no.1
• /
• pp.89-97
• /
• 2007

This paper describes a load simulator with power recovery capability, which is based on the voltage source converter-inverter set. The load simulator can save the electric energy that should be consumed to test the operation and performance of the power quality compensator and the power equipment. The load simulator consists of a converter-inverter set with a DSP controller for system control and PWM pulse generation. The converter operates as a universal load to model the linear load and the non-linear load, while the inverter feed the energy back to the power source with harmonic compensation. the performance of proposed load simulator was analyzed with scaled-model experiment, interconnected with the active power filter. The experimental results confirms that the proposed load simulator can be utilized to test the performance of active power filter.

• Journal of Advanced Marine Engineering and Technology
• /
• v.28 no.5
• /
• pp.746-753
• /
• 2004

In this paper, the Power Management System(PMS) which based on a decision making system according to power strategy is proposed and implemented. PMS is designed to have functions of power monitoring. controlling, synchronizing load sharing and monitoring of driving engine, etc. PMS consists of the internet communication system(ICS). Remote Management System(RMS) and Sensor Driver System (SDS) ICS transmits the monitoring and supervisory data via Internet to Remote Management System(RMS) in real-time SDS detects various power system data on local generator and utility via I/O interface system. I/O interface system receives various status data and outputs control signals. Implemented PMS is tested with dummy signal to verify proposed functions and shows good results. For future study implemented PMS will be tested under real load condition to merchandize.

• Journal of the Korean Society of Industry Convergence
• /
• v.4 no.3
• /
• pp.311-318
• /
• 2001

The application of a pulsed power system is being extended to a environmental and industrial fields. The non-dissolution waste water pollutants from industrial plants can be processed by applying high voltage pulses with a fast rising time (a few nanoseconds) and short duration (nano to microseconds) in a pulsed corona discharge reactor. The nano-pulse generator with a magnetic switch has been developed. Its corona current in load can be adjusted by pulse width and repetition rate. we investigated the performance of the nano-pulse generator using the dummy load which is composed of resistor and capacitor equivalent to the actual reactor. This paper descibes the electrical characteristics of the nano-pulse generator that produces a 300 ns pulse at maximum repetition rate of 400 pps with a voltage of 40 kV across a $640{\Omega}$ load. In this paper we briefly discuss a configuration of system and test results.

• Journal of the Semiconductor & Display Technology
• /
• v.23 no.2
• /
• pp.100-106
• /
• 2024

To generate the plasma required in dry cleaning processes, the plasma chamber must be supplied with a high-quality AC voltage with a voltage of more than 1 kV and a frequency of 400 kHz. In the existing research, many methods to supply high power have been studied, but how to improve the quality of the power for high-quality plasma has been relatively little studied. In this paper, we propose a study to improve the quality of RF power circuit for high-quality plasma generation in dry cleaning method. Existing methods in the environment of full-bridge-based RF power circuits must perform PWM duty control in the light load region. This causes distortions in the waveform, resulting in poor power quality, which directly leads to poor plasma quality. To solve these problems, a half-bridge switching method is proposed and the improvement in waveform quality is verified. To verify the feasibility of the design and control algorithm proposed in this paper, an RF power circuit prototype is fabricated and the proposed design and control method is verified through simulation and actual experiments under dummy load.

• Proceedings of the KIPE Conference
• /
• 2003.07a
• /
• pp.260-263
• /
• 2003

When ICP(Inductive Coupled Plasma type etching and wafer manufacturing is being processed in semiconductor process, a noxious gas in PFC and CFC system is generated. Gas cleaning dry scrubber is to remove this noxious gas. This paper describes a power source device, 2MHz switching frequency class 2kW RF Generator, used as a main power source of the gas cleaning dry scrubber. The power stage of DC/DC converter is consist of full bridge type converter with 100kHz switching frequency Power amplifier is push pull type inverter with 2MHz switching frequency, and transmission line transformer. The adequacy of the circuit type and the reliability of generating plasma in various load conditions are verified through 50$\Omega$ dummy load and chamber experiments result.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.32 no.3
• /
• pp.217-222
• /
• 2008

Equal channel angular pressing (ECAP) is one of the effective methods to produce bulk-nano materials by accumulating plastic strain into the workpiece without changing its cross-sectional shape in the multi-pass processing. However, the forming load becomes higher for manufacturing large specimens using conventional solid or split dies because of friction, flash formation, and usage of dummy specimen. In the present investigation, better split die was designed to reduce the forming loads and improve the geometrical accuracy of the specimen in the multi-pass ECAP. The new die exit channel was also designed to reduce the friction effect. Experiments with AA1050 specimens with a square cross-section were carried out to examine the design goal using the proposed split dies for routes A and C up to four passes. The numerical forming simulations were used to determine the effective geometry of various die models in the present work.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.16 no.1
• /
• pp.24-29
• /
• 2017

There is a need for explosion experiments for explosion-related research. However, there are many restrictions in performing an actual experiment. Therefore, in this paper, an alternative method of overcoming the constraints of an explosion experiment has been conducted using a passenger behavior analysis program called MADYMO to assess and analyze the human body injury due to explosion load. To increase the reliability of the analysis, a drop test has been conducted with the analysis. We provide a new framework for performing the analysis. In future, we will further develop our research with the goal of reducing the opportunity cost for the study of the human body injury.

• International Journal of Automotive Technology
• /
• v.8 no.2
• /
• pp.185-191
• /
• 2007

The new FMVSS 208, 213, 225 regulations include automatic suppression of airbags to prevent low-risk airbag deployment and the use of child seats with a rigid-bar anchor system. The regulations mean that children must sit in the rear seat, but do not include other specific safety measures for their protection. In the rear, restraint equipment consists of three-point shoulder/lap belts for the outside seats and a static two-point lap belt in the middle, with no additional devices such as pretensioners or load limiters; this is far from optimal for children. This study investigated injury rates using a 3-year-old-child dummy. ECE R44 sled tests used a booster, a speed of 48 km/h, and a 26- to 32-g rectangular deceleration pulse. While seated on a booster, the dummies were restrained by an adult shoulder/lap three-point belt. HIC_15 msec, Chest G and Nij were somewhat lower with an emergency locking retractor (ELR)+pretensioner+load limiter than with only an ELR or with ELR+pretensioner. However, the current seat-belt system results in injury rates that exceed the limit for OOP performance under the new FMVSS 208 regulations.