반도체 공정 온도제어용 칠러의 실험적 연구

차동안(Dong An Cha),권오경(Oh Kyung Kwon),오명도(Myung Do Oh) 대한기계학회 2011 大韓機械學會論文集B Vol.35 No.5

반도체 제조를 위한 공정에서는 과도한 열이 발생한다. 따라서 Chamber 내의 웨이퍼나 주변온도를 일정하게 유지할 수 있도록 온도의 정밀제어가 요구된다. 반도체 칠러는 산업용 칠러와는 다르게 운전조건이 24시간 년중 지속되므로 반도체 칠러는 전력소비량이 대단히 크며, 냉동기의 최적 운전제어를 통한 저소비전력 칠러 개발이 대단히 필요하다. 국내에서 판매되고 있는 반도체 칠러는 수입품에 비해 전력소비가 높아 제품 경쟁력이 낮은 실정이다. 이에 따라 본 연구에서는 국내에서 개발된 반도체 칠러에 관한 실험적 연구를 통하여 칠러의 부하변화 실험, 온도 상승 하강실험, 제어정밀도 실험 등을 통하여 칠러의 에너지절감 방향을 제시하고자 한다. 실험을 통하여 칠러의 냉각능력은 2.1~3.9 ㎾, EER은 0.56~0.93으로 측정되었다. 제어정밀도는 0℃에서 ±1℃, 30℃ 이상 설정에서는 ±0.6℃로 향상되는 것으로 나타났다. Excessive heat may be generated during the semiconductor manufacturing process. Therefore, precise control of temperature is required to maintain a constant ambient temperature and wafer temperature in the chamber. Compared to an industrial chiller, a semiconductor chiller’s power consumption is high because it is in continuous operation for a year. Because of this high power consumption, it is necessary to develop an energy-efficient chiller by optimizing the operation. The competitiveness of domestic products is low because of the high energy consumption. We experimentally investigated a domestic semiconductor by conducting load change, temperature rise and fall, and control precision experiments. The experimental study showed that the chiller had 2.1?3.9 ㎾ of cooling capacity and 0.56?0.93 of EER. The control precisions were ±1°C and ±0.6°C when the setting temperatures were 0°C and 30°C respectively.

잠열 축열식 칠러시스템의 제어 방식에 따른 성능 분석

강병하(Byung Ha Kang),김동준(Dong Jun Kim),이충섭(Choong Seop Lee),장영수(Young Soo Chang) 대한설비공학회 2017 설비공학 논문집 Vol.29 No.11

A chiller, having a thermal storage system, can contribute to load-leveling and can reduce the cost of electricity by using electricity at night. In this study, the control experiments and simulations are conducted using both conventional and advanced methods for the building cooling system. Advanced approaches, such as the “region control method”, divide the control region into five zones according to the size of the building load, and determines the cooling capacities of the chiller and thermal storage. On the other hand, the “dynamic programming method” obtains the optimal cooling capacities of the chiller and thermal storage by selecting the minimum-cost path by carrying out repetitive calculations. The “thermal storage priority method” shows an inferior chiller performance owing to the low-part load operation, whereas the chiller priority method leads to a high electric cost owing to the low utilization of thermal storage and electricity at night. It has been proven that the advanced control methods have advantages over the conventional methods in terms of electricity consumption, as well as cost-effectiveness. According to the simulation results during the winter season, the electric cost when using the dynamic programming method was 6.5% and 8.9% lower than that of the chiller priority and the thermal storage priority methods, respectively. It is therefore concluded that the cost of electricity utilizing the region control method is comparable to that of the dynamic programming method.

제어방식에 따른 반도체 공정용 칠러에 관한 연구

차동안(Dong An Cha),권오경(Oh Kyung Kwon) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11

Excessive heat may occur during semiconductor manufacturing process. Thus, precise control of temperature is required to maintain constant ambient-temperature and also wafer-temperature in the chamber. Compared to an industrial chiller, semiconductor chiller's power consumption is very high due to its continuous operation for a year. Considering the high power consumption, it is necessary to develop an energy efficiency chiller by optimizing operation control. Therefore, in this study, an experimental study is conducted to determine the optimal refrigerant charge for the semiconductor chiller. The performance of PWM and EEV method chiller, are compared through the experiments, refrigerant circulation rate, temperature rise and fall, control precision. Optimum charge of refrigerant for the cooling capacity, 3.7 ㎾ was measured as 3.5 ㎏. For the EEV-chiller, power consumption, refrigerant circulation rate, and system pressure tends to increase. For the experiment of temperature rise and fall, the EEV-chiller takes the time of 39minutes, and the power consumption of 3.52 ㎾. For the precise control experiment, at the temperature of 0℃ the deviations are ±0.5℃ for PWM method, ±1.5℃ for EEV method.

다수의 직렬-직렬 대향류 물 냉각기를 사용한 공조시스템의 성능

Nguyen Minh Phu,이근식(Geun Sik Lee) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.11

When water chillers are arranged in series-series counter-flow (SSCF), the compressor lift of each chiller is decreased, in contrast to water-chillers in parallel. That means that the compressor power of SSCF chillers is lower than that of parallel chillers. In this paper, the models of main components in an air conditioning system were formed and verified in order to predict the performance of the whole system with SSCF chillers. Results were shown that the performance had maximum with 3 SSCF chillers when the system was operated with the normal set points. 26% enhancement of the performance was achieved with the optimal-set-point operation in the case of 3 SSCF chillers but no advantage was found in the cases of more than 4 SSCF chillers.

용액 저장 탱크가 결합된 태양열 구동 흡수식 칠러의 건물 냉방부하별 성능 특성 분석

최형원(Hyung Won Cho),정재희(Jaehui Jeong),강용태(Yong Tae Kang) 대한설비공학회 2022 대한설비공학회 학술발표대회논문집 Vol.2022 No.6

용액 저장 탱크가 결합된 태양열 구동 흡수식 칠러의 건물 냉방부하별 성능 특성 분석

최형원(Hyung Won Cho),정재희(Jaehui Jeong),강용태(Yong Tae Kang) 대한설비공학회 2022 대한설비공학회 학술발표대회논문집 Vol.2022 No.6

The solar-assisted absorption chiller is integrated with the thermal energy storage tanks to implement elongated operation with solar energy as well as to complement the incompatibility of the time gap between the cooling load of the building and the supply of renewable energy source. In this research, the thermal energy storage capacity and the operating characteristics of the system merging a single-effect absorption chiller employing water-lithium bromide as a working fluid and three thermal energy storage tanks were investigated. This system transforms the solar thermal energy into the chemical potential of water-lithium bromide solution to store the thermal energy and has the advantage of not requiring insulation of the thermal energy storage tank. Numerical investigation has been conducted to analyse the ratio between the mass flow rate of refrigerant to absorption chiller and that of thermal energy storage tank, which has been set as a key parameter to optimize the system performance. Based on the data of the cooling load of the residential building in July, which requests the largest cooling load, the feasibility study of energy management plan is conducted to establish the optimization of system performance. The regenerated water vapor is condensed to be supplied to absorption chiller for producing the cooling effect during the daytime and the rest is stored in the refrigerant storage tank to response to the cooling load during the night. This supply ratio of refrigerant is the significant parameter to optimize the operation of the system according to the specific cooling load of the building. Based on a hotel with cooling area of 30 m2, the optimized thermal energy storage density is estimated of 106.7 kWh/m3. The optimal cooling capacity of the evaporator of the absorption chiller is 2.2 kW at the ratio of thermal energy storage of 0.53, which means 53% generated refrigerant should be stored to effectively relieve the cooling load without solar energy. Simultaneously, the maximum thermal energy storage density is estimated of 216.4 kWh/m3, and that of the cooling capacity of the evaporator of absorption chiller is 4.46 kW.

반도체 공정용 칠러의 채널별 제어특성에 관한 실험적 연구

김현중(Hyeon Joong Kim),권오경(Oh Kyung Kwon),차동안(Dong An Cha),김용찬(Yong Chan Kim) 대한기계학회 2011 大韓機械學會論文集B Vol.35 No.12

본 연구에서는 전자식 팽창밸브를 적용한 반도체 공정용 칠러에 관한 실험적 연구를 통해 시스템 특성을 파악하였다. 또한 온도 변화에 따른 신속한 대응을 할 수 있도록 온도상승 및 하강실험, 부하변화에 따른 온도영역별 제어정밀도 실험을 함으로써 각 제어 방식에 따른 운전 특성을 파악하였다. 온도상승 시 소비전력은 8.9 ㎾로 측정되었으며 CH1이 37.5분, CH2가 39.5분이 소요되었으며, 온도하강에는 총 26.5분이 소요되었다. 부분부하가 적용되는 경우 전부하가 적용되는 경우에 비해 제어정밀도의 변화폭이 큰 것으로 나타났으며 스텝모터 구동방식을 적용한 CH2의 제어정밀도가 상대적으로 우수한 것으로 나타났다. 냉각수를 이용한 냉각사이클 영역에서 소비전력은 1.8 ㎾로 냉동사이클을 적용한 방식에 비해 절반가량으로 감소된 것으로 나타났다. 본 연구는 실험결과를 바탕으로 반도체 공정용 칠러의 최적제어방안을 제시하였다. The characteristics of a semiconductor chiller system with EEV have been experimentally studied. Three experiments on temperature changes (increase and decrease), load variation, and control precision were conducted to investigate the operating characteristics of the semiconductor chiller. The power consumption was 8.9 ㎾ during increase in temperature. The required time was 37.5 min for CH1 and 39.5 min for CH2. Moreover, the time required for falling temperature was 26.5 min. The control precision for partial load operation was relatively low compared to that of a full load operation. In addition, the CH2 equipped with a step motor showed better control precision. The power consumed by the chiller for process cooling water was 1.8 ㎾, which was one-half of that consumed during the refrigeration cycle. The objective of this study is to provide an optimal control guideline for the semiconductor chiller design.

듀얼채널을 적용한 반도체공정용 칠러의 실험적 연구

차동안(Dong An Cha),권오경(Oh Kyung Kwon) 대한설비공학회 2010 설비공학 논문집 Vol.22 No.11

Excessive heat occurs during semiconductor manufacturing process. Thus, precise control of temperature is required to maintain constant chamber-temperature and also wafertemperature in the chamber. Compared to an industrial chiller, semiconductor chiller’s power consumption is very high due to its continuous operation for a year. Considering the high power consumption, it is necessary to develop an energy efficient chiller by optimizing operation control. Therefore, in this study, a semiconductor chiller is experimentally investigated to suggest energysaving direction by conducting load change, temperature rise and fall and control precision experiments. The experimental study shows the cooling capacity of dual-channel chiller rises over 30% comparing to the conventional chiller. The time and power consumption in the temperature rising experiment are 43 minutes and 8.4 kWh, respectively. The control precision is the same as ±1℃ at 0℃ in any cases. However, it appears that the dual channel’s control precision improves to ±0.5℃ when the setting temperature is over 30℃.

에너지절감형 반도체 공정용 칠러에 관한 실험적 연구

차동안(Dong-an Cha),권오경(Oh-kyung Kwon),윤재호(Jae-ho Yun),김대열(Dae-yeol Kim) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.5

Excessive heat may occur during semiconductor manufacturing process. Thus, precise control of temperature is required to maintain constant ambient-temperature and also wafer-temperature in the chamber. Compared to an industrial chiller, semiconductor chiller's power consumption is very high due to its continuous operation for a year. Considering the high power consumption, it is necessary to develop an energy efficiency chiller by optimizing operation control. The competitiveness of the domestic products is low because of its high energy consumption. Therefore, in this study, a domestic semiconductor chiller is experimentally investigated to suggest energy-saving direction by conducting load change, temperature rise and fall and control precision experiments.

난방운전 조건에서 히트펌프 칠러의 성능특성

박경만(Kyoung-Man Park),엄유식(Yu-Sik Um),이상재(Sang-Jae Lee),권영철(Young-Chul Kwon) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-

In the present study, the performance characteristics of R-410A heat-pump chiller in heating mode are experimentally investigated to understand capacity and reliability at the standard, the defrost, the low temperature and the on-off cycle conditions. Heating capacity, water flow rate and COP of R-410A heat-pump chiller are 11.4㎾, 33 l/min and 2.94, respectively. Heating capacity at low temperature condition decreases as the outside temperature decreases. From defrost and on-off cycle conditions, it is confirmed the reliability of R-410A heat-pump chiller.