• 전력전자학회논문지
• /
• 제25권3호
• /
• pp.227-234
• /
• 2020

This paper presents the methods for the modeling and parameter optimization of the electric vehicle battery. The state variables of the battery are defined, and the test methods for battery parameters are presented. The state-space equation, which consists of four state variables, and the output equation, which is a combination of to-be-determined parameters, are shown. The parameter optimization method is the key point of this study. The least square of the modeling error can be used as an initial value of the multivariable function. It is equivalent to find the minimum value of the error function to obtain optimal parameters from multivariable function. The SIMULINK model is presented, and the 10-hour full operational range test results are shown to verify the performance of the model. The modeling error for 25 degrees is approximately 1% for full operational ranges. The comments to enhance modeling accuracy are shown in the conclusion.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2019년도 전력전자학술대회
• /
• pp.17-19
• /
• 2019

본 논문에서는 전기자동차(EV) 충전기용 위상천이 풀브리지(PSFB) 컨버터의 정류기 다이오드 전압 스트레스를 저감하기 위한 새로운 형태의 클램핑 회로를 제안한다. 제안하는 회로는 하나의 커패시터로 구성된 매우 단순한 구조임에도 불구하고, 정류기 다이오드의 전압 스트레스를 큰 폭으로 감소시킨다. 뿐만 아니라, 해당 회로는 프리휠링 구간의 전류를 감소시키며, 출력 인덕터의 사이즈 또한 줄일 수 있다는 장점을 지닌다. 따라서 제안된 컨버터는 정류기 다이오드의 도통손실을 큰 폭으로 저감하여 고효율을 달성할 수 있으며, 간단한 구조의 클램핑 회로와 줄어든 출력 필터 사이즈에 의해서 고밀도화를 달성할 수 있다. 제안된 컨버터의 타당성은 3.3kW, $270-420V_{DC}$의 CC-CV 모드 충전 조건하에서 실험하여 검증되었다.

• 전자통신동향분석
• /
• 제36권4호
• /
• pp.118-134
• /
• 2021

In this study, we provide trends on alternative fuel vehicles promoted by postal agencies in 10 countries in North America, the EU, and Asia. It describes the specifications of most EV vehicles in operation, plans, and strategies to replace existing internal combustion engines with new vehicles in the future and provides the current status of alternative vehicle charging networks in each postal agency. This paper will help postal agencies, logistics companies, automobile companies, motorcycle companies, and even individuals who want to use vehicles with alternative fuels, such as electric vehicles, on strategies to establish and implement before introducing and operating the vehicles.

• 한국생산제조학회지
• /
• 제21권6호
• /
• pp.920-925
• /
• 2012

A study of vehicle weight lightening has been progressed to reduce the fuel consumption. In this paper, the body floor in an EV (Electric Vehicle) bus has been applied by composites as CFRP and GFRP. In order to analyse a various reliability and safety, an experiment and FEM analysis was carried out to obtain weight lightening. Especially, the joint. An effective design is obtained through an experiment as well as FEM analysis. Results of stress analysis of GFRP material showed twice as much displacement than those of CFRP material. Among three kinds of joint methods, the bond joint method is occurred to a substantial shape change in the body and floor. It is found that the rivet joints are fairly suitable for stress sustaining capability.

• 한국산학기술학회논문지
• /
• 제17권2호
• /
• pp.590-595
• /
• 2016

최근 미국은 전기자동차에 대한 보조금을 30%이상 인상하는 방안을 추진하고 있고, 유럽 각국도 2020년까지 100만대, 2030년까지 600만대의 전기자동차를 보급할 계획인 독일을 중심으로 보급과 개발 정책을 확대하고 있다. 전기자동차 개발을 단순한 기술적인 트렌드가 아닌, 장기적인 에너지 안보와 전체 사회 시스템을 변화시킬 수 있는 가능성 측면에서 접근하고 있기 때문이다.[1] 국내 또한 전기자동차 보급 목표가 증가하고 경쟁이 심화됨에 따라 신규 블루 오션 시장으로 급부상하고 있다. 현재 완속 충전기(Home Charger)의 경우 국내에서는 2015년부터 정부 지원 설치가 중단될 계획인데, 전기자동차의 보급에 최대 장애 요인 중 하나인 충전 인프라 부족을 최적화 된 저가형 Home Charger 개발로 전기자동차 민간 보급 조기 활성화에 기여하고자 한다. 본 논문에서는 IEC 61851-1과 IEC 61851-22 규격을 분석하여 저가형 충전기의 심야전력 알고리즘을 개발하였으며, 완속 충전기의 가격 저감과 편리성을 위해 기존의 충전기 시스템에 ATmega128, Bluetooth 모듈의 추가 구성을 통한 UI의 LCD 패널을 스마트폰 어플로 변경하였다.

• 전력전자학회논문지
• /
• 제21권5호
• /
• pp.411-417
• /
• 2016

Theoretical IPMSM control technique is complicated, and reliability is low because of the changing parameters. Further, in case of general look-up table designing method which obtains torque characteristics (according to current and speed) or torque characteristics (according to magnetic flux through the entire control region), obtaining a precise result can be difficult and has the disadvantage taking too much time to establish a current look-up table. In this paper, the new auto maximum torque point tracking (MTPT) algorithm that automatically finds the optimum stator d - q axis electric current reference through the entire speed region is devised; consequently, it could establish a 3D look-up table with torque characteristics according to current and speed. In case of using the devised auto MTPT algorithm, the result value detailed was obtained in comparison with the generalized look-up design technique, and checked to reduce the current look-up table establishment time.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제13권10호
• /
• pp.4988-5012
• /
• 2019

As a subset of the Internet of Things, the Internet of Energy (IoE) is expected to tackle the problems faced by the current smart grid framework. Notably, the conventional day-ahead power scheduling of the smart grid should be redesigned in the IoE architecture to take into consideration the intermittence of scattered renewable generations, large amounts of power consumption data, and the uncertainty of the arrival time of electric vehicles (EVs). Accordingly, a day-ahead power scheduling system for the future IoE is proposed in this research to maximize the usage of distributed renewables and reduce carbon emission caused by the traditional power generation. Meanwhile, flexible charging mechanism of EVs is employed to provide preferred charging options for moving EVs and flatten the load profile simultaneously. The simulation results revealed that the proposed power scheduling mechanism not only achieves emission reduction and balances power load and supply effectively, but also fits each individual EV user's preference.

• Journal of Power Electronics
• /
• 제16권6호
• /
• pp.2359-2367
• /
• 2016

Inductive power transfer (IPT) systems have become increasingly popular in recharging electric vehicle (EV) batteries. This paper presents an investigation of a series parallel/series (SP/S) resonant compensation network based IPT system for EVs with further optimized circular pads (CPs). After the further optimization, the magnetic coupling coefficient and power transfer capacity of the CPs are significantly improved. In this system, based on a series compensation network on the secondary side, the constant output voltage, utilizing a simple yet effective control method (fixed-frequency control), is realized for the receiving terminal at a settled relative position under different load conditions. In addition, with a SP compensation network on the primary side, zero voltage switching (ZVS) of the inverter is universally achieved. Simulations and experiments have been implemented to validate the favorable applicability of the modified optimization of CPs and the proposed SP/S IPT system.

• Journal of Power Electronics
• /
• 제13권3호
• /
• pp.429-436
• /
• 2013

Online simulations are utilized to reduce time and cost in the development and performance optimization of plug-in hybrid electric vehicle (PHEV) and electric vehicles (EV) systems. One of the most important factors in an online simulation is the accuracy of the model. In particular, a model of a battery should accurately reflect the properties of an actual battery. However, precise dynamic modeling of high-capacity battery systems, which significantly affects the performance of a PHEV, is difficult because of its nonlinear electrochemical characteristics. In this study, a dynamic model of a high-capacity battery cell for a PHEV is developed through the extraction of the equivalent impedance parameters using electrochemical impedance spectroscopy (EIS). Based on the extracted parameters, a battery cell model is implemented using MATLAB/Simulink, and charging/discharging profiles are executed for comparative verification. Based on the obtained results, the model is optimized for a high-capacity battery cell for a PHEV. The simulation results show good agreement with the experimental results, thereby validating the developed model and verifying its accuracy.

• 전력전자학회논문지
• /
• 제25권1호
• /
• pp.37-43
• /
• 2020

This study proposes a 7kW low-voltage DC-DC converter (LDC) using a coupled inductor (CI) for heavy hydrogen electric transport vehicles. The LDC uses a phase-shift manner for soft switching. SiC-MOSFET is used to reduce the loss of reverse recovery current through the use of a high switching frequency. LDC is require large transformer and inductor because of large output current. The size of transformer and inductor can be reduced by deviding the transformer and inductor into two pieces each. This work presents the experimental results of the proposed circuit.