http://doi.org/10.5207/JIEIE.2024.38.5.335

Sung-Min Ma ; Chul-Soo Kim

In order to build a modeling language for lighting products, this study uses 40 TRIZ principles that can be used to resolve contradictions that arise when solving TRIZ problems in combination with 50 formative expansion keywords and applies them to the process of establishing a formative language for lighting products, thereby achieving innovation. We plan to build an archive of various formative languages for realistic and creative design and study ways to use it as prompt data for lighting design using Midjourny, a generative AI design tool.

http://doi.org/10.5207/JIEIE.2024.38.5.342

Jaeho Seo ; Soyeon Park ; Yong Wook Lee

In this study, we scrutinize the continuous wavelength tuning capability of the narrowband multiwavelength spectrum in an optical fiber multiwavelength filter using contiguous quarter-wave polarization transformation. The multiwavelength filter is based on a polarization-diversity loop structure composed of a polarization beam splitter, two equal-length polarization-maintaining fiber segments, four quarter-wave plates (QWPs) used to tune the spectrum wavelength, and a half-wave plate utilized to maximize the spectrum visibility. By utilizing the transmittance function of the filter derived through the Jones matrix formulation, we theoretically found specific orientation angles of the four QWPs for the continuous wavelength tuning of the narrowband multiwavelength spectrum, which could induce an extra phase difference φ from 0° to 360° in the filter transmittance. From the spectral calculation at the eight selected orientation angle sets of the four QWPs, it was revealed that the wavelength tuning of the narrowband multiwavelength spectrum could be implemented at 0.1nm intervals by properly adjusting the orientation angles of the four QWPs and this approach could be easily extended for the continuous wavelength tuning of the spectrum. The theoretical prediction was then experimentally verified.

http://doi.org/10.5207/JIEIE.2024.38.5.349

Sang-Wuk Shin ; Jin-Sung Rho ; Min-Su Lim ; Jong-Min Lim

This paper presents the development of a Touchdown and Lift off Area light for marking the landing area in airports. To achieve this, the design requirements specified by the Federal Aviation Administration (FAA) and the International Civil Aviation Organization (ICAO) were analyzed and incorporated into the optimization design of the optical and power units. Additionally, a prototype Touchdown and Lift off Area light was produced, and its optical, structural, and electrical performance characteristics were measured to verify that the key performance requirements reflected in the design were met. Performance characteristic measurement data confirmed that the designed and manufactured Touchdown and Lift off Area light satisfied the regulatory minimum average intensity of 30.816 cd (>15 cd) and the chromaticity standard range (x=0.1333, y=0.6667 for Green). Furthermore, it was confirmed through respective measurement data that the structural and electrical key performance characteristics exceeded the standard thresholds. As a result of this study, the developed Touchdown and Lift off Area light is set to be installed at the dedicated vertical take-off and landing (VTOL) vertiport in Goheung, Jeollanam-do, which is being prepared for urban air mobility (UAM) demonstrations by the Ministry of Land, Infrastructure and Transport.

http://doi.org/10.5207/JIEIE.2024.38.5.357

Jin-uk Jeong ; Jiwon Ryu ; Sangguk Jung

The adoption of smart lighting systems in the public sector domestically has been slow due to the lack of standardized protocols. To address this, ETRI has developed an open API and data model specifications for smart lighting systems. In this paper, we analyze the layered communication protocols used globally in smart lighting systems and examine the structure of smart lighting systems as outlined in the KS C 7751 series, a Korean Industrial Standard. Furthermore, we analyzed ETRI's open API and data model specifications, testing them against products from domestic companies to verify their compliance. The results confirm the interoperability of smart lighting systems across backbone and local networks. We anticipate that this study will contribute to the widespread adoption and activation of smart lighting systems domestically.

http://doi.org/10.5207/JIEIE.2024.38.5.363

Zeno Rizqi Ramadhan ; Yong Hyun Kim

High-performance yttrium aluminum garnet nanophosphors doped with cerium (YAG:Ce) were prepared by a simple precipitation method. The use of sodium hydroxide (NaOH) and sodium bicarbonate (NaHCO3) as precipitating agents successfully yielded Ce-doped monoclinic yttrium aluminum (YAM:Ce) and YAG:Ce nanoparticles, respectively. The structural, energetic, and optical properties of the Ce-doped yttrium aluminum oxide nanoparticles were systematically studied. Optimization of the preparation conditions for the YAG:Ce nanophosphors by post-thermal and pressing treatments resulted in remarkably improved light emission and crystallinity. We believe that this simple, low-cost, and environmentally friendly precipitation method and post-treatment approach will contribute to the production of high-performance YAG:Ce nanophosphors.

http://doi.org/10.5207/JIEIE.2024.38.5.368

Young-Gook Jung

This paper describes the improvement of the dynamic characteristics of the output voltage of the three-phase Z-source AC/DC converter (ZSC) using a fuzzy logic controller. The fuzzy controller uses a single input fuzzy theory, and the analysis structure of a simple fuzzy controller is derived through a triangular membership function. The fuzzy controller is designed by setting the membership function of the fuzzy rule. The operation mode of the ZSC with the output voltage fuzzy controller is analyzed, and the relationship between modulation index and buck-boost voltage gain are derived. Experiments were conducted to verify the validity of the proposed method for improving the transient characteristics of the output voltage. The experiment uses a DSP (TMS320F28335) controller to calculate the reference of the modulation index and generate PWM pulses. The performance of the previous PI controller and fuzzy controller for improving the transient characteristics of the output voltage control of the ZSC is compared. As a result, it can be observed that the ZSC is capable of the buck-boost of the output voltage, and the fuzzy controller has better performance than the previous PI controller through transient state analysis.

http://doi.org/10.5207/JIEIE.2024.38.5.378

Dong-Geun Lee

Recently the diversification of applications for motor drive inverters, there is an increasing trend of applying inverter systems in large-scale fields. Especially as the capacity of inverter systems increases, improving efficiency can effectively reduce power loss. Therefore, research on various topologies and control methods for high efficiency is actively being conducted. This paper focuses on improving the efficiency of the inverter itself and the power quality of the output current to enhance motor efficiency and overall system efficiency for large-capacity motor drive systems. To achieve this, a 3-Level inverter for large-capacity motor drives was designed and implemented, and the results were validated through experiments. Specifically, the validation was carried out by comparing the efficiency of the 3-Level inverter system with that of the existing 2-Level inverter system under different motor drive load capacities.

http://doi.org/10.5207/JIEIE.2024.38.5.383

Young-Gook Jung

In this study, we present an active peak detection technique (APD) that predicts the input voltage and DC voltage by detecting the input current of a three-phase active power filter (APF). The output voltage is predicted by APD, and the input voltage is predicted using the input current, switching function, and estimated value of DC voltage. The proposed method can be implemented using easy formulas and circuit methods without the need for difficult and complex sampling formulas like the observer. PSIM simulation is performed to prove the feasibility of this study. The input voltage and DC voltage are predicted under the conditions of a 220V voltage, a load of 25Ω, and the DC voltage of the APF changing rapidly in three stages from 430V, and using this, it is possible to control the unit input power factor of the APF system. For a situation where the load suddenly decreased from 25Ω to 15Ω, the results of the method using the sensor and the proposed method are consistent with each other. Lastly, the input power factor(P.F) of the APF according to load changes is 0.99, and the total harmonic distortion (%THD) of the input current is maintained below 8%.

http://doi.org/10.5207/JIEIE.2024.38.5.391

Jeong-Heum Park

This study attempted to simulate the current-voltage characteristics using “Simple Model” and “Zero-Hysteresis Model” among the techniques to model the behavior of the battery cells and evaluate their usefulness through comparison with the experimental values. To this end, a battery charging and discharging system was implemented to show information on the current-voltage of the cell during the charging and discharging process and compared with the modeling results. As a result, both models showed results that generally match the experimental values in the actual application range despite the high difficulty of modeling, so it was confirmed that they are modeling tools that can be used in BMS (Battery Management System) design.

http://doi.org/10.5207/JIEIE.2024.38.5.397

Do-Yun Kim

This paper presents a method for detecting resolver offset in Permanent Magnet Synchronous Motors (PMSM) using LabVIEW software. PMSM systems rely on accurate position sensing for efficient control, and the resolver is a key sensor. However, resolver offset can degrade control accuracy. The research focuses on developing a real-time signal processing and offset detection algorithm using LabVIEW. The experimental results demonstrate that the proposed method enhances detection precision and improves system stability. Future work will focus on optimizing the algorithm and expanding its applicability to complex control environments.