The development of high specific surface area and mesoporous activated carbons is required to improve the electrochemical performance of EDLC. In this study, kenaf-derived activated carbons (PK-AC) were prepared for high-power-density EDLC via phosphoric acid stabilization and steam activation. The pyrolysis behavior of kenaf with respect to the phosphoric acid stabilization conditions were examined via TGA and DTG. The textural properties of PK-AC were studied with N2/ 77 K adsorption–desorption isotherms. In addition, the crystalline structure of PK-AC was observed via X-ray diffraction. The specific surface area and mesopore volume ratio of PK-AC were determined to be 1570–2400 m2/ g and 7.7–44.5%, respectively. In addition, PK-AC was observed to have a high specific surface area and mesopore volume ratio than commercial coconut-derived activated carbon (YP-50F). The specific capacitance of PK-AC was increased from 77.0–99.5 F/g (at 0.1 A/g) to 49.3–88.9 F/g (at 10.0 A/g) with activation time increased. In particular, K-P-15-H-9–10 observed an approximately 35% improvement in specific capacitance at a higher current density of 10.0 A/g compared to YP-50F. As a result, the phosphoric acid stabilization method was confirmed to be an efficient process for the preparation of high specific surface area and mesoporous biomass-derived activated carbons, and the kenaf-derived activated carbons prepared by this process have great potential for application as electrode active materials in high-power EDLC.

The most basic control algorithm of the electric power steering system in the Korean refrigerating cart CoCo was first commercialized as a prototype in 2022 after the Motor Driven Power Steering (Electric Power Steering) was verified and applied to automobiles. In order to overcome the heavy load of small machines such as refrigerating carts weighing 750Kgf, the driver's great power is required, which can cause muscle skeletal disorders, causing many female drivers to complain of pain, and recently applied electric steering technology because it was urgent. In this study, we study a control algorithm that complements the stability of the existing control algorithm applied to the electric power steering device for electric carts and analyze and verify the steering performance of refrigerated carts through analysis using MATLAB/SIMULINK.

In this study, static and dynamic analysis verification was performed to apply the fuel cell system to the E-PTO of the Wire aerial vehicle. First, structural analysis was performed to improve the weak points that occurred. Next, vibration analysis was performed on the fuel cell system for which structural safety review was completed according to the wide-band irregular vibration test standard. The analysis results showed that resonance occurred in a specific frequency band and local stress was high, so stiffness reinforcement was performed. After reinforcing the stiffness, stress was reduced through a decrease in transient response characteristics and resonance phenomenon.

With the continuous prosperity and development of the marine industry, the number of ships is increasing while greenhouse gas emissions are rising. In order to meet the relevant international ship emission regulations, the solution of developing electric ships is proposed. As the core device of the electric ship propulsion system, the maturity and applicability of power battery technology play a key role in the development of the electric ship. This article introduces the principles and advantages of the fuel cell, lithium-ion battery as well as supercapacitor battery, respectively, and analyzes the application status and challenges of power batteries in existing electric ships. The development direction and problems to be solved of power battery in current and future ship applications are put forward, which can provide a reference for further research.

EPS(Electric Power Steeing) has been a popular system in the automotive industry since 2000 after the technology and safety was validated. The Korean Refrigerated Carts like Hankook Yogurt Coco was developed for the first time in the world. However this carts system and other small tranporting carts has no EPS. Thus the drivers of carts needed a EPS to avoid the burden when steeing a big weighted cart with 750Kgf as many women drivers complain the pain on their shoulders. This paper describes the application of EPS on Korean refrigerated carts with simulation results and experimental data shows the improvement of steering efforts.

국제해사기구에서는 선박에서 배출되는 질소산화물 및 이산화탄소 등에 관한 환경규제를 꾸준하게 강화하고 있다. 이에 친환 경 요소를 바탕으로 하는 전기추진시스템의 수요가 증가하고 다양한 선박에 적용되며 연구개발이 꾸준하게 진행되고 있다. 전기추진시스 템은 신뢰성을 높이고 선내 배치를 용이하게 하기 위한 이중화 구성이 주로 채택되며 실제 장비나 공간을 가상 세계에 쌍둥이처럼 구현 하고 현실 세계의 정보와 데이터를 가상 세계와 통합하여 실제 환경에서 발생할 수 있는 상황을 컴퓨터로 시뮬레이션 함으로써 결과를 미리 예측할 수 있는 디지털트윈 기술의 접목을 통하여 전기추진시스템의 안전성 확보를 위한 연구 또한 매우 활발하게 진행되고 있다. 본 연구에서는 전기추진선박의 디지털트윈 기술개발을 위한 전력관리시스템 이중화에 대한 검증을 FMEA를 바탕으로 분석 후 선급에서 제시하는 이중화 FMEA 기준을 바탕으로 실제 선박 운항 조건에서 전력관리시스템의 단일 장비 고장의 일차 피해와 이차 피해 및 전체 시스템의 영향을 분석하여 추가 피해를 방지하기 위한 보상기능으로 전력관리시스템의 역할과 알고리즘을 제안하였으며 실제 테스트를 통해 추진력 보존이 개선되었음을 검증하였다.

The ultimate goal of this development is a hybrid solar energy storage device. It supplies stable power to the load due to the emergency generator that compensates for the power shortage due to solar power generation. We have developed a stand-alone photovoltaic power generation and energy storage system with a dual inverter that extends the performance life of the PV system. It solves the problem of shortening the lifespan of battery due to repetition of charge / discharge of PV system and supplies stable power to load due to emergency generator that compensates for power shortage due to solar power generation, and furthermore, A stand-alone photovoltaic power generation system having a dual inverter for extending the life span and a control method thereof. We have also developed an optimized energy solution that enables us to save and use the remaining surplus power in the ESS to save energy through efficiency, optimization and substantial energy savings.

Recently, the outboard engine system of internal combustion engine is widely used in the field of small ship propulsion. However, the internal combustion engine has serious problems of energy depletion and environmental problems, so electric propulsion methods are being studied. In this paper, we have developed important motors and controllers of electric propulsion system for small marine outboard motors. The motor design was performed through the motor characteristics analysis method, and the 30Kw system was developed through the BEMF processing circuit and the power conversion circuit by the embedded microprocessor. This study was carried out through government supported projects and achieved quantitative targets through accredited institutions.

본 연구는 융복합기술을 사용하여 국내 자동차 산업의 배터리 및 전기시스템과 수상레저기구 중 접근이 용이한 수상오토바이를 결합하여 전기 동력 추진식 수상오토바이 개발과 전기 동력 추진식 수상오토바이 실용화를 위한 등록 및 제작을 위해 전기 동력 추진식 수상오토바이의 안전검사 기준(안)과 형식승인 기준(안)을 개발하였다. 전기 동력 추진식 수상 오토바이 인증기준은 기존 내연기관 동력 수상오토바이의 인증기준과 선박 전기 시스템과 관련된 인증기준을 기본으로 구조 및 시스템 설치 안과 전기시스템 안의 두 분류로 구분을 하였고, 최종적으로 안전검사 기준(안)과 형식승인 기준(안)으로 개발하였다. 안전검사 기준(안)의 내용은 총 7개의 범주로 구분되어 수상오토바이의 안전한 운행을 위한 설비의 확인을 목적으로 작성되었고, 형식승인 기준(안)은 총 7개의 범주로 구분되어 수상오토바이의 안전한 제작을 위한 목적으로 작성되었다. 본 연구를 통해 국내 친환경 수상오토바이 제작의 환경 조성과 전기동력 추진 선박의 인증기준에 대한 정책 수립 기초 자료로 활용이 가능하다.

The limitations and problems of the rechargeable battery and short mileage per one electric charging have not been overcome at the electric vehicles. To solve these problems, the hybrid vehicle has been developed by securing the performance of automotive with the conventional internal combustion engine and the environmental benefit. Meanwhile, the electric UTV (utility terrain vehicle) which has this environmental benefit has been widely used for factories, parks, leisure and agricultural areas. In this study, the electric UTV was fabricated and attached the auxiliary power drive systems including the photovoltaic power generation system into this electric vehicle in order to make up the hybrid (motor + photovoltaic) vehicle system. As the range of the hybrid UTV would be extended over 20% than that of the existing golf cart per one electric charging through this successful development, the dynamic stiffness was improved through light-weight body design.

다이오드 정류기가 AC-DC 컨버터로 산업현장에서 널리 응용되고 있다. 그러나 입력전류에 많은 저차고조파가 포함되어 전력변환 장치의 공급전압을 왜곡시켜 전력의 품질을 저하시키므로 이를 완화시킬 수 있는 적절한 설비가 필요하다. 이러한 문제점들을 개선하기 위해 본 논문에서는 정류기의 출력단에 보조 전원장치를 설치하여 고조파를 저감하는 장식을 제안하였다.

In this study, We have taken LED lamps which are widely used recently, applied it to training ship's cabin and lounge, cafeteria, engine control room and analyzed the power consumption and illumination with existing fluorescent. Replacing 40W, 20W of fluorescents with 22W, 11W of same number of LED lamps, It showed 45% of power consumption savings and resulted to more than 20% of illumination improvement. If applied to all areas of the ship, It would surely contribute to great amount of energy savings and illumination improvement.

This study is designed to predict the overall electric power load, to apply the method of time sharing and to reduce simultaneous load factor of electric power when authorized by user entering demand plans and using schedules into the user’s interface for