http://doi.org/10.5207/JIEIE.2025.39.2.84

Chin-Woo Yi ; Seong-Kuk Hur

In this paper to compare the economical efficiency of light sources for interior lighting last 10 years. The raw data were collected in February 2013 at Orlando Florida, USA and May 2024 at Chicago Illinois, USA. The compared light sources are incandescent lamps, halogen lamps, compact fluorescent lamps, tubular fluorescent lamps and LED lamps. The variables are average light flux, prices, maintenance costs, average lamp life, average input power and power rates. And we investigated the changes in unit cost and efficacy over 10 years for three types of fluorescent lamps, two types of incandescent lamps, and two types of LED lamps for which information on lamp type, power consumption, luminous flux, and price could be obtained. The results show that the most economical light source among the compared light sources was the fluorescent lamp in 2013, but it changed to the LED lamp in 2024. Efficacy has remained almost...

http://doi.org/10.5207/JIEIE.2025.39.2.89

Hyunyoung Lee ; Ju Yeon Kim

The purpose of this study is to review the plan to contribute to the applicability and distribution policy of zero energy building (ZEB) through the design, manufacture, and performance analysis of solar cell integrated LED(Light Emitting Diode) convergence module that combines solar power generation technology and RGB LED display technology. The module design was verified under various environmental conditions by convergence IBC (Interdigitized Back Contact) half-cut solar cell and RGB LED device based on a printed circuit board (PCB) to minimize electrical loss and install transparent glass and color glass, respectively. The photovoltaic performance of the manufactured prototype was evaluated and analyzed according to the KSC IEC 61215 standard, and the maximum output (Pmax) was measured as 46.52W. The LED display performance was analyzed as white luminance 628.4cd/m² and green luminance...

http://doi.org/10.5207/JIEIE.2025.39.2.101

Kyung-Min Lee ; Chul-Won Park

Nowadays, renewable energy sources are expanding for low-carbon green growth and Net Zero. With the increase in IDC, EV, and digital loads, attention is focused on the design and adequacy of Hybrid power grid that links LVDC and MVDC system to reduce conversion losses. Therefore, power flow and fault calculation are essential for designing and optimally operating the Hybrid power grid. In this paper, for steady-state analysis and protective relaying of Hybrid power grid, we propose a power flow and fault calculation technique. The proposed technique can be applied to AC, DC, and Hybrid power grid, and is implemented as program using the C language. Also, The superiority of the proposed power flow and fault calculation technique is proven through comparison with the simulation results of commercial S/W such as ETAP and PSCAD.

http://doi.org/10.5207/JIEIE.2025.39.2.107

Shin Kim ; In-Sik Lee ; Young-Kuk Kim

This paper investigates the variations in plasma generation voltage based on different power supply types, including DC, AC, and pulsed sources, to gain deeper insights into their effects on plasma formation and overall efficiency. Aluminum was chosen as the plasma electrode due to its high electrical conductivity and widespread availability. Experiments were conducted both in ambient air and using aluminum oxide (Al2O3) as the dielectric material to examine the impact of environmental and material conditions on the plasma generation process. The power supply outputs ranged from 1 to 10kV at a frequency of 10kHz. For the AC source, both square and sine waveforms were utilized. DC and AC voltages were generated with a signal generator and amplifier to control the reference voltage and frequency. Pulsed power was produced using two configurations: a 50μs pulse width generated by a signal...

http://doi.org/10.5207/JIEIE.2025.39.2.113

Young-Lak Kim ; Chun-Hyung Cho

In modern society, high-speed transmission of large amounts of information is possible through broadband communication networks, but the use of broadband communication systems inevitably leads to problems of cross-channel interference and noise. In this study, we showed that RF harmonic signals can be dramatically removed using a broadband high-power multi-switch filter module to minimize interference in adjacent bands that commonly occurs in broadband communication systems. The overall design consists of a broadband RF switch design and an RF channel filter design to remove RF harmonic signals. Note that 8 channel filters were designed to remove harmonics in a wide band of 30∼512MHz. We then connected it to a UVHF power amplifier and measured the generated harmonics and observed that the out-of-band suppression amount was in the range of ?60∼-80dB, which is better than the...

http://doi.org/10.5207/JIEIE.2025.39.2.120

Ok-Hyeong Lee ; Hyung-Woo Lee ; Kyo-Beum Lee

This paper presents a method for reducing switching losses and minimizing the harmonic distortion (THD) of the current in an interior permanent magnet synchronous motor (IPMSM) drive system by employing a phase current-based discontinuous pulse width modulation (DPWM) and a dead time compensation technique. Switching losses are effectively reduced by implementing a phase current-based DPWM. The phase current-based DPWM method is implemented by the offset voltage based on the phase angle of the current and clampsapppled to the switch where the absolute value of the phase current is maximized. Furthermore, the current polarity is identified based on the phase angle, allowing for the application of a dead time compensation voltage aligned with this polarity to mitigate voltage distortion induced by dead time. This technique effectively reduces the THD of the output current in a 2-level inverter operating...

http://doi.org/10.5207/JIEIE.2025.39.2.128

Seung-Min Cho ; Kyeong-Hwan Kim ; Tae-Geun Kim ; Sung-Guk Yoon ; Kyung-Bin Song

This study proposes short-term load forecasting algorithm using an improved exponential smoothing method to improve the accuracy of day-ahead load forecasting in spring. The proposed algorithm defines the range of temperature insensitivity in spring and calculates daily sensitivity of hourly temperature. Daily exponential smoothing coefficients are optimized to minimize forecasting errors. Case studies were performed on the proposed algorithm to calculate the forecast error of day-ahead load forecasting in the spring of 2022 and 2023. The proposed algorithm showed an improvement of the average prediction accuracy in spring in by 12.85%p for two years compared to the exponential smoothing and LSTM algorithm errors of the short-term load forecasting S/W of the Korea Power Exchange.

http://doi.org/10.5207/JIEIE.2025.39.2.136

Ung-Hui Yun ; Jun Yoon ; Jin-Gyu Kim

Corona discharge occurs in regions with uneven electric fields, where ionization happens around electrodes with small curvature radius. The resulting ions move through the electric field, transferring momentum to neutral gas molecules, generating ionic wind. Ionic wind offers advantages like fast response, low noise, and low maintenance, making it useful for electric propulsion and cooling technologies. While typical ionic wind generation involves applying voltage to electrodes with small curvature radius, experiments like ion lifter studies have shown differing characteristics when the polarity is reversed. The reasons for these differences in discharge behavior remain unexplained. Therefore, this study examines the effects of applied voltage polarity on corona discharge and ion wind characteristics. The corona onset voltage was lowest for positive polarity discharge(4.70kV), with higher values for other polarities. Discharge...

http://doi.org/10.5207/JIEIE.2025.39.2.141

Kyeong-Hwan Kim ; Bo-Sung Kwon ; Seung-Min Cho ; Kyung-Bin Song

Policies to expand renewable energy for carbon neutrality have led to a rapid increase in small-scale solar power generation. This has resulted in annual minimum electric power load occurring during daytime on weekends and holidays in spring and fall. During these times, solar and nuclear power account for the majority of generation, leading to difficulties for grid stability. To ensure stable grid operation, a mid-term plan and an accurate forecasting technique for minimum electric power load are essential. This paper proposes a technique that uses the basic electric power load and a relative coefficient method to predict minimum electric power load in spring and autumn. It calculates the monthly basic electric power load, incorporating GDP influences while excluding temperature effects, and estimates Sunday demand using a relative coefficient method, thereby predicting minimum electric power load while reflecting...

http://doi.org/10.5207/JIEIE.2025.39.2.148

Tae Heoung Kim

This paper presents the design of a drive motor for an electric vehicle. Selecting an optimal combination of poles and slots is crucial in drive motor design. The number of poles influences the switching frequency of the switching element, motor size, output, efficiency, and overall system cost, necessitating careful consideration during the design process. In this study, 8-pole 48-slot and 6-pole 36-slot drive motors, both featuring a pole-to-slot ratio of 1:6, were developed. Even with the same pole-to-slot ratio, motor characteristics vary due to differences in magnetic flux per pole depending on the number of poles. This paper analyzes the saturation and iron loss of the 8-pole 48-slot and 6-pole 36-slot motors. Furthermore, the validity of the proposed design was confirmed through manufacturing and performance evaluation.

http://doi.org/10.5207/JIEIE.2025.39.2.155

Hoon Jung ; Joon-Ho Ahn

Partial discharge (PD) refers to a localized dielectric breakdown occurring in a solid or liquid electrical insulation system under high voltage stress, without fully bridging the space between conductors. It is critical as it can significantly impact the reliability and lifespan of high-voltage electrical equipment such as transformers, switchgear, and cables. This paper presents an artificial intelligence (AI) model designed to classify patterns of various partial discharges. To evaluate the model, training data for each type of partial discharge, generated through UHF(Ultra High Frequency) sensors, were collected. These data were then converted into 2D representations using Phase Resolved Partial Discharge (PRPD) analysis. The proposed models were built on deep learning algorithms, specifically the Visual Geometry Group (VGG), which is a type of Convolutional Neural Network (CNN). The classification accuracies achieved for DI, FE, and...