• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 B
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• pp.923-925
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• 2004

A lot of conventional automotive components driven by mechanical power source are being replaced with electrical ones to comply with the demands of market and customer, therefore the amount of electric energy used in a vehicle will be increased continuously. The increment of electric power demand causes interest on new higher power system such as 42V Power Net, and furthermore necessity for development of energy storage device is highlighted recently. This paper present the design of the BLDC motor for electric air-conditioner in 42V system and compare with the characteristics of several type BLDC motor.

• 설비공학논문집
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• 제18권1호
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• pp.66-72
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• 2006

This article presents the optimal operation of an air conditioner using thermoelectric modules. A prototype of air conditioner using four thermoelectric modules has been designed and built. The system performance with evaporative cooling for hot side of the module are studied in detail for several operating parameters, such as input power to the thermoelectric module, fans and pump. It is found that the optimal input voltage to the thermoelectric module and pump is selected for the best system performance based on the cooling capacity and the COP at a given operating condition. It is also found that both the cooling capacity and COP of a system is increased with an increase in the input power to fans. The cooling performance could be improved when the ambient temperature is increased and the relative humidity is decreased since the evaporative cooling at the hot side has been increased.

• 한국수소및신에너지학회논문집
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• 제24권5호
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• pp.444-450
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• 2013

The distribution performance of refrigerant distributors in air conditioner evaporators was examined numerically and experimentally. Internal flow analysis of the distributor by CFD found that the distance from the socket to the cone, the angle of the cone and the base area of the cone were the most important factors affecting refrigerant distribution ability and vortex creation. To enhance distribution performance, two distributors with improved internal structures were designed. To test these new structures, distribution performance was also analyzed by CFD and an empirical experiment was carried out using the water-nitrogen. Experimental results on the distribution fraction of each distributor hole showed a good agreement with the results of the CFD analysis. Thus, the new design of the distributors enhanced distribution performance of the refrigerant distributors.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 제2회 학술대회 논문집 일렉트렛트 및 응용기술전문연구회
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• pp.1-8
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• 2000

Automotive electronics as we know it today encompasses a wide variety of devices and systems. Key to them all, and those yet to come. is the ability to sense and measure accurately automotive control parameters. In other words, sensors and actuators are the heart of any automotive electronics application. The important of sensors and actuators cannot be overemphasized. The future growth of automotive electronics is arguably more dependent on sufficiently accurate and low-cost sensors and actuators than on computers, controls, displays, and other technologies. Without them, all of controls system - engine. transmission. cruise, braking, traction, suspension, steering, lighting, windshield wipers, air conditioner/hearter - would not be possible. Those controls, of course, are key to car operation and they have made cars over the years more drivable, safe, and reliable. In this lecture, the principle and future trends of electronic control gasoline engine will be discuss.

• 한국산업융합학회 논문집
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• 제10권1호
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• pp.21-26
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• 2007

As DDI or GDI engine discharges very low heat due to its high thermal efficiency, the heat source is not enough for heating the passenger compartment in cold climate condition. To remedy the heating problem, the conventional HFC-134a automotive air-conditioning system has been attempted to run as a heat pump mode. Futhermore, an auxiliary electric heater of new type was equipped to the heat pump air-conditioning loop as a new approach. Hence, a proto-type heat pump air conditioner has been made and tested to investigate the feasibility of the HFC-134a automobile air-conditioning system that could be worked as a heat pump. The experiment results showed that the sufficient heating capacity could be obtained by adding a heat pump with an new electric type auxiliary heater into the conventional heat core in low temperature condition.

• 설비공학논문집
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• 제28권11호
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• pp.428-433
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• 2016

The fin and tube heat exchanger using a two-port tube has in air-conditioner heat exchanger because heat transfer performance. This study investigates the feasibility of a fin and tube heat exchanger using two-port copper tube by mechanical expansion. The optimum size of the tube-expanding bullet for the heat exchanger using two-port tube was through numerical calculation. The heat exchanger using a two-port tube was fabricated by mechanical expansion, and the heat exchanger performance was evaluated condensation and evaporation experiments. Compared to the heat exchanger of a conventional circular tube, the pressure drop per unit length of the heat exchanger with a two-port tube decreased. Compared to the heat exchanger using a conventional circular tube, the overall heat transfer coefficient of heat exchanger with a two-port tube increased up to 13% in the case of condensation, and up to 25% in the case of evaporation. The two-port tube heat exchanger outperforms conventional heat exchanger for air conditioner with a inner grooved circular tube.

• 설비공학논문집
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• 제24권12호
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• pp.823-829
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• 2012

In this study, the performance of mobile air conditioner(MAC) systems to which the refrigerants R134a and R1234yf were used was evaluated to compare the characteristic of automotive refrigeration cycles with refrigerant. The experimental setup of a MAC consists of an belt driven compressor, a condenser, an evaporator and a block type thermal expansion valve. The drop-in test on MAC were carried out under variable compressor speed from 800 to 2500 rpm. Performance test by using R1234yf and R134a in the same system revealed low the charge amount and mass flow rates for using R1234yf, that is, up to 10% and 17%, respectively. The compressor discharge temperature of R1234yf is $8^{\circ}C$ lower than that of R134a. The cooling capacity with R1234yf system decreased by 4~7% compared with R134a system. In addition, The COP of R1234yf system is lower 3~4% than that of R134a system.

• International Journal of Air-Conditioning and Refrigeration
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• 제15권3호
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• pp.101-107
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• 2007

Indoor air quality becomes of a concern recently in view of human health. This study investigates the air diffusion performance and the air change efficiency of a classroom, when outdoor air is introduced in two different ways in addition to the heating/cooling operation of a ceiling-mounted heat pump. A CFD analysis has been performed to investigate the effect of the discharge angle of the air jets from the heat pump for both parallel and series types of outdoor air system. It is observed that the series type creates more uniform indoor environment compared to the parallel type in general. It can be concluded the discharge angle should not be larger than 40o for the parallel type, in order not to generate thermal stratification in the room.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.875_876
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• 2009

Recently, Interior Permanent Magnet Synchronous Motor(IPMSM) is widely used in the industry applications such as power train for hybrid vehicles and compressor motors of air-conditioner due to its high power density and wide speed range. There are some ways for confirming of maximum power in IPMSM. However, This paper suggests that there is a way about making sure maximum power by reducing turn numbers of armature winding. Setting up the voltage equation through the equivalent circuit and vector diagram of IPMSM first, and then estimating the parameter and power of IPMSM by changing the turn numbers of armature winding and voltage. In order to satisfy output power, the turn numbers of armature winding is changed by using the characteristic analysis, and then checking whether secure maximum power or not.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2015년도 전력전자학술대회 논문집
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• pp.139-140
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• 2015

차량용 에어컨 시스템은 엔진의 가동(주행 또는 공회전)에 의해 발생되는 에너지를 이용하여 운전자가 원하는 차량 실내온도를 유지시켜주는 장치를 말한다. 이러한 기계식 에어컨 시스템의 작동은 엔진 구동력의 일부를 활용하고 있어 자동차의 연비와 큰 관련성 있다. 때문에 하절기 작업 대기시나 차량 내 야간취침 등이 빈번한 상용차량의 경우 운전자의 운행습관에 따라 연료 소비량이 증가하는 단점을 가지고 있다. 본 논문에서는 이러한 단점을 개선하고자 대형 상용차량이 정차중인 무시동 기간에도 일정 온도의 유지가 가능 하도록 전력변환장치가 적용된 에어컨 시스템을 제안하였다.