3.3kV(105A) COMPACT RACK TYPE 고압 인버터 시스템의 방열 성능 향상을 위한 열유동 해석

김선영(S. Y. Kim),김성대(S. D. Kim),유성열(S. R. Ryoo),유남규(N. K. You),김태범(T. B. Kim),홍찬욱(C. O. Hong) 한국전산유체공학회 2014 한국전산유체공학회 학술대회논문집 Vol.2014 No.5

With ever-rising concerns about saving of fossil fuel resource, there have also been an increasing demand for using of energy more efficiently. The electric motor driven inverters can be a great help to improve energy efficiency. They are used to control the motor speed to the actual need. Therefore the use of them can lead to reduce energy consumption. In particular, the medium voltage(MV) drive systems which are used for pumps, fans, steel rolling mills and tractions have widespread applications in the industry. They covers power ratings from 0.4MW to 40MW at the medium-voltage level of 2.3kV to 13.8kV. However, the majority of the installed MV drive systems are in the 1MW to 4MW range with voltage rating from 3.3kV to 6.6kV. Recently, they also have been required to reduce size and weight like other power electronic equipments. In this paper, we studied on the 3.3kV(105A) compact rack type inverter system for improving of cooling efficiency. At first, we confirmed the tendency of temperature to compare with computational simulation using ANSYS ICEPAK and actual experimental tests. And then we researched thermal performance improvement designs in order to reduce temperature of the transformer for the safe operation. As a result, we found out more efficient solution by thermal-fluid analysis.

3.3㎸(105A) COMPACT RACK TYPE 고압 인버터 시스템의 방열 성능 향상을 위한 열유동 해석

김선영(S.Y. Kim),김성대(S.D. Kim),유성열(S.R. Ryoo),유남규(N.K. You),김태범(T.B. Kim),홍찬욱(C.O. Hong),고한서(H.S. Ko) 한국전산유체공학회 2014 한국전산유체공학회지 Vol.19 No.3

With ever rising concerns about saving of fossil fuel resource, there have been an increasing demand for use of energy more efficiently. The electric motor driven inverters can be a great help to improve energy efficiency. They are also used to control the motor speed to the actual need. Therefore the use of them can lead to reduce energy consumption. In particular, the medium voltage(MV) drive systems used for pumps, fans, steel rolling mills and tractions have widespread applications in the industry. They cover power ratings from 0.4㎿ to 40㎿ at the ㎹ level of 2.3㎸ to 13.8㎸. The majority of the installed MV drive systems however, are in the 1㎿ to 4㎿ range with voltage rating from 3.3㎸ to 6.6㎸. But they are required to reduce size and weight like other power electronic equipments. In this paper, we studied on the 3.3㎸(105A) compact rack type inverter system for improving the cooling efficiency. At first, we confirmed the tendency of temperature with computational simulation using ANSYS ICEPAK and actual experimental tests. And then we researched thermal performance improvement designs in order to reduce temperature of the transformer for the safe operation. It can reduce temperature of transformer that using pipe type flow guide in the system. As a result, we found out more efficient solution by thermal-fluid analysis.

열유동 해석을 통한 4kW급 태양광 인버터 히트싱크 최적화 설계

김선영(S.Y. Kim),홍찬욱(C.O. Hong),김성환(S.H. Kim),박주현(J.H. Park),이승구(S.G. Lee),유성열(S.R. Ryoo) 한국전산유체공학회 2013 한국전산유체공학회 학술대회논문집 Vol.2013 No.5

There has been most interested in the renewable energy not only ballooning oil prices but also Fukusima Daiichi nuclear accident. Photovoltaic energy of all the renewable energy is highly demanded because it is used convenient if only sunlight is available. Photovoltaic Inverters or PV Inverters utilizing a photovoltaic system control the generated power of the maximize solar energy collected from photovoltaic panels. The basic function of PV inverters is to convert the direct current(DC) power coming from a photovoltaic panel into the alternating current(AC). Recently, almost the research for PV inverters has been conducted to reduce the size and weight of them and to improve the power density and the electric power conversion efficiency of the system. So to ensure PV’s competitive price in the market, it is specifically significant to find optimum heat sink designed to cool power semiconductor. In this research, we considered geometrical parameters of heat sink for the selecting proper size, the position of power semiconductor, and the guide of flow in order to find the condition of the safe operation. Also, thermal-fluid analysis was conducted a study on the PV inverter for 4kW class that are being developed in our company and used the ANSYS ICEPAK specialized in CFD simulation of power electronics equipment. And then we found out the temperature of the power switching chips, the distribution of surface temperature on heat sink and the flow condition between fins.

IGBT 냉각용 히트파이프-히트싱크 열유동해석

유성열(S.R. Ryoo),김선영(S.Y. Kim),홍찬욱(C.W. Hong) 한국전산유체공학회 2013 한국전산유체공학회 학술대회논문집 Vol.2013 No.10

A heat sink(HS) using heat pipes for electronics systems had been studied. The experimental results indicate that a cooling capacity of up to 500W at an overall temperature difference of 40 can be attainable. The heat sink design for the power semiconductor in the inverter also showed that a computer simulation can predict the most of the parameters involved. To do so, however, the interior temperature distribution had to be verified by experimental results. The current simulation results were close to the experimental results in acceptable range. The simulation study showed that the design of heat sink heat pipe(HSHP) can be a good results to predict the effects of various parameters involved in the optimum design of the inverter to drive motor.

저압 인버터용 Busbar 재질 변화에 따른 열유동-전자계 연성해석

정원목(W.M.. Jeoung),목진성(J.S. Mock),김선영(S.Y. Kim),홍찬욱(C.O. Hong),김정빈(J.B. Kim),김경서(K.S. Kim),유성열(S.R. Ryoo) 한국전산유체공학회 2012 한국전산유체공학회 학술대회논문집 Vol.2012 No.11

The Busbar is generally fabricated by molding a number of copper plates, that is used for electric system such as low voltage inverter and converter. It is conducted a study on replacing as other low-cost materials because of upsurge in raw materials for industry. In previous studies, numerical approaches were investigated to predict the effect of the temperature distribution of replacing to this busbar from copper to aluminum. In this study, thermal-fluid-electromagnetic coupled numerical analyses are performed to take into account the Joule heat effect on the numerical evaluation of the busbar material characteristics. Comparisons with experimental results show that the proposed coupled analysis provides more reliable results than the conventional analyses in predicting the temperature characteristics.

1.5 MVA SYSTEM 고압 인버터의 열유동 해석과 실험을 통한 정합성 검증 평가

목진성(C.S. Mock),유성열(S.R. Ryoo),김선영(S.Y. Kim),안상국(S.K. Ann),전재현(J.H. Jun),홍찬욱(C.O. Hong),나승호(S.H. Na),김경서(K.S. Kim) 한국전산유체공학회 2012 한국전산유체공학회 학술대회논문집 Vol.2012 No.5

As the demand for saving energies has been getting higher all over the world the development for high-voltage and high capacity inverters has been achieved to reduce energy by controling the consumption patterns of industrial electric equipments. H-Bridge Multi-Level high-voltage inverter being researched is the single phase H-Bridge inverter by using low-voltage power semiconductor devices. It can make high-voltages close to a sine wave by connecting composed cells on series. This is a topology without filters because of the low input and output harmonic, and usages of it have been expanded in metal, oil, natural gas and electricity generation industries. The optimal operation conditions on these kinds of high-voltage inverters are varied by running environment conditions, and the performance tests for thermal stability of inner electric semiconductors changes are partially impossible because of facilities. In this research, the junction temperature of power electronics devices, distribution of surface temperature on heat sink and inner temperature and velocity of cells and systems have been drawn as the results by using ANSYS ICEPAK specialized in CFD simulation of power electronics equipments to secure the thermal reliability of cells and systems for 1500kW high-voltage inverters. Through these outcomes the ventilation structures and an effective arrangement of heat components of cell-based inverters could be applied to the plan for a uniform flow distribution of a high-voltage inverter system. Moreover, the consistency of thermal-flow simulation was proven by comparison of actual temperature through the cell-based performance tests.