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

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.