• International Journal of Automotive Technology
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• 제6권5호
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• pp.537-544
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• 2005

This paper presents the efficiency measurement and energy analysis for a parallel HEY. Using the HEV test rig, the efficiency of each powertrain component is measured for a given driving cycle including the regenerative braking system. Accompanied by the efficiency measurements, a detailed energy analysis is performed. Based on the efficiency measurement and energy analysis, a HEV performance simulator is developed. Using the simulator, the HEV performance is evaluated for a mild hybrid system. It is expected that the HEV simulator developed can be used to obtain further optimization potentials.

• 전기화학회지
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• 제15권3호
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• pp.115-123
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• 2012

리튬이차전지의 수요가 소형 휴대용 전자기기에서 중대형 전기자동차와 에너지저장장치로 변화함에 따라, 요구되는 전지 특성도 크게 달라지고 있다. 10년 이상의 장기 신뢰성, 팩 수준의 안전성, 가격 경쟁력 확보 등 기존 소형 전지보다 크게 강화된 요구 조건뿐만 아니라, 고출력 특성도 함께 필요로 한다. 그런데, 출력을 측정하기 위해서는 전압과 전류가 동시에 측정 및 제어되어야 하기 때문에, 기존의 단위셀 용량 측정보다 훨씬 어렵다. 또한, 측정 방법의 선택뿐만 아니라 출력유지시간, 충전상태(State-of-Charge, SOC), Cut-off 조건, 측정온도 등의 측정 조건에 따라서도 그 측정값이 크게 달라지는 경향이 있다. 본 논문에서는 HPPC (Hybrid Pulse Power Characterization)법, J-pulse(Japan Electric Vehicle Association Standards, JEVS D 713)법, 정출력 측정법(Constant Power Measurement)의 측정 원리 및 실제 실험에 어떻게 적용해야 하는지 설명하고, HEV(Hybrid Electric Vehicle)용 단위셀을 이용해 출력법간 측정 결과를 비교 분석한다.

• 대한기계학회논문집A
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• 제40권9호
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• pp.801-805
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• 2016

플러그인 하이브리드 전기자동차는 내연기관과 전기모터를 동력원으로 사용하며 주행 상황에 따라 다양한 주행 모드을 갖는다. 주행 모드에는 전기모터로만 주행하는 EV 모드(전기주행), 내연기관으로 주행하는 엔진 운전 모드, 두 개의 동력원을 이용하는 HEV 모드(하이브리드 주행)가 있다. 특히 병렬형 구조를 갖는 하이브리드 전기자동차는 모드변환에 따라 엔진 클러지가 접합되거나 해제되는데, 클러치 접합 시 나타나는 충격은 차량의 승차감에 영향을 주기 때문에 중요하다. 본 논문에서는 플러그인 하이브리드 전기자동차의 성능 시뮬레이터를 MATLAB/Simulink를 이용하여 개발하고, 시뮬레이션 결과를 통해 엔진 클러치 접합 시 나타나는 충격 특성을 분석하였다.

• 한국자동차공학회논문집
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• 제15권2호
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• pp.182-186
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• 2007

This paper studied performance characteristics of hybrid automotive to replace existing fossil fuel vehicles. Specially, about power split type HEV that is T-HEV's drive system when a vehicle drives at steady speed, monitored both output of each engine, motor and generator and battery SOC (state of charge) and analyzed performance characteristic of power transmission system and electricity power parts. This study shows those that acquired and analyzed information from signals between HCU and each controller of actual T- vehicle. From this study, it is confirmed that each conditions of EV and HEV drive can be a improvement with respect to the fuel efficiency of vehicles.

• 한국자동차공학회논문집
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• 제9권5호
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• pp.122-130
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• 2001

In this paper, an operational algorithm for a 2-shaft parallel hybrid electric vehicle is suggested for the minimization of operation cost. The operation cost is obtained as a summation of the engine fuel cost and the motor electricity cost. The electrical cost function is estimated in case of motoring, and generating when the recuperation is carried out during the braking. In addition, weight function is introduced in order to maintain the battery state of charge. Based on the operation algorithm, the optimal engine operation point that minimizes the operation cost is obtained with respect to the required vehicle power for every state of charge of battery. The optimal operation point provides the optimal power distribution of the engine and the motor for a required vehicle power Simulation was performed and the fuel economy of the hybrid vehicle was compared to that of the conventional vehicle. Simulation results showed that hybrid vehicle's fuel economy can be improved as much as 45∼48% compared to the conventional vehicle's.

• Journal of Mechanical Science and Technology
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• 제18권1호
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• pp.30-36
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• 2004

In this paper, operation algorithms for a parallel HEV equipped with a relatively small motor are investigated. For the HEV, the power assist and the equivalent fuel algorithms are proposed. In the power assist algorithm, an electric motor is used to assist the engine which provides the primary power source. Tn the equivalent fuel algorithm, the electric energy stored in the battery is considered to be an equivalent fuel, and an equivalent brake specific fuel consumption for the electric energy is proposed. From the equivalent fuel algorithm, distribution of the engine power and the motor power is determined to minimize the fuel consumption for a given battery state of charge (SOC) and a required vehicle power. It is found from the simulation results that the fuel economy and the final battery SOC depend on the motor discharge energy and it is the best way to charge the battery only by the regenerative braking, not by the engine to improve the overall fuel efficiency of the HEV with the relatively small motor.

• Journal of Mechanical Science and Technology
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• 제15권11호
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• pp.1490-1498
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• 2001

In this paper, a regenerative braking algorithm is presented and performance of a hybrid electric vehicle (HEV) is investigated. The regenerative braking algorithm calculates the available regenera tive braking torque by considering the motor characteristics, the battery SOC and the CVT speed ratio. When the regenerative braking and the friction braking are applied simultaneously, the friction braking torque corresponding to the regenerative braking should be reduced by decreasing the hydraulic pressure at the front wheel. To implement the regenerative braking algorithm, a hydraulic braking module is designed. In addition, the HEV powertrain models including the internal combustion engine, electric motor, battery, CVT and the regenerative braking system are obtained using AMESim, and the regenerative braking performance is investigated by the simulation. Simulation results show that the proposed regenerative braking algorithm contributes to increasing the battery SOC which results in the improved fuel economy. To verify the regenerative braking algorithm, an experimental study is performed. It is found from the experimental results that the regenerative braking hydraulic module developed in this study generates the desired front wheel hydraulic pressure specified by the regenerative braking control algorithm.

• International Journal of Automotive Technology
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• 제5권3호
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• pp.201-208
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• 2004

Response characteristics of the CVT system for a parallel hybrid electric vehicle (HEV) are investigated. From the experiment, CVT ratio control algorithm for the optimal engine operation is obtained. To investigate the effect of the CVT system dynamic characteristics on the HEV performance, a hardware in the loop simulation (HILS) is performed. In the HILS, hardwares of the CVT belt-pulley and hydraulic control valves are used. It is found that the engine performance by the open loop CVT ratio control shows some deviation from the OOL in spite of the RCVs open loop control ability. To improve the engine performance, a closed loop control of the CVT ratio is proposed with variable control gains depending on the shift direction and the CVT speed ratio range by considering the nonlinear characteristics of the RCV and CVT belt-pulley dynamics. The HILS results show that the engine performance is improved by the closed loop control showing the operation trajectory close to the OOL.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제4B권4호
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• pp.157-169
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• 2004

Motor & generator operation at widely variable speeds is needed in various applications but hybrid and electric vehicle (HEV) stand out today, as quite a few companies are launching this year their mass production of HEVs. The quest for better starter-generators is far from ended, though. The present review paper unfolds a comparative critical evaluation of various starter-generators and their control for HEV. Induction, interior PM synchronous, transverse-flux PM synchronous, switched reluctance, together with claw-pole and biaxial excitation PM synchronous (BEGA) configurations with their control are all considered in system evaluations.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.366-369
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• 2005

최근 환경 및 에너지 문제가 자동차 산업의 중요한 이슈로 인식되면서 하이브리드 자동차(Hybrid Electric Vehicle) 기술과 연료 전지 자동차(Fuel Cell Vehicle)등이 주목받고 있다. 특히 하이브리드 자동차는 요구되는 동력과 생성되는 동력의 차이 때문에 순시 동력 저장 장치 (peak power buffer)가 필요한데, 반복적인 충/방전 싸이클에서 용량의 감소 없이 높은 단위 질량당의 동력과 에너지를 가지며 부피, 효율, 수명 면에서도 우수한 플라이 휠 에너지 저장장치가 이러한 동력 저장 장치로 적합하다. 본 논문은 하이브리드 자동차를 위한 플라이 휠 에너지 저장 장치의 현 상태 (state of art)를 기술한다. 첫번째로, 플라이 휠 에너지 저장장치의 기원과 배경을 설명한다. 두 번째로 하이브리드 자동차를 위한 플라이 휠 에너지 저장 장치의 세부 사항을 요약하고, 플라이 휠 에너지 저장을 이용한 하이브리드 자동차의 예와 플라이 휠 에너지 저장장치의 설계 쟁점과 자동차에 적용시키기 위한 최근 기술적 진보를 논의한다. 마지막으로, 플라이 휠 에너지 저장장치의 파급 효과와 다른 적용 예를 소개한다.