南京航空航天大学学报
南京航空航天大學學報
남경항공항천대학학보
JOURNAL OF NANJING UNIVERSITY OF AERONAUTICS & ASTRONAUTICS
2010年
2期
133-139
,共7页
王世山%刘泽远%杜亚平%王星华
王世山%劉澤遠%杜亞平%王星華
왕세산%류택원%두아평%왕성화
电力电缆%间接耦合场%有限元%功率损耗%温升
電力電纜%間接耦閤場%有限元%功率損耗%溫升
전력전람%간접우합장%유한원%공솔손모%온승
power cable%indirect coupled-field%finite element method (FEM)%power losses%temperature rises
建立了多导体电力电缆置于具有散热孔的托架上时3D有限元时谐磁场模型,在计及各金属涡流效应的条件下,得到所有导体单元的功率损耗密度.以此功率体密度损耗为栽荷,建立了电缆系统的"热-流体"直接耦合场模型,求解了电缆系统各导体的温升,由此完成一次完整的"磁场"与"热-流体"场间接耦舍的求解.由于电缆导体电阻率与温度密切相关,形成"磁场"与"热-流体"场间接耦合的双向耦合.反复迭代,可求解得到当热点为90℃时导体的电流,即为电缆的载流量.以无铠装单载流和有铠装三并联栽流电缆为例,采用间接耦合法计算和测量了系统的总功率、电流分布、导体热点温度.计算和测量一致性说明了双向间接耦合有限元模型建立的正确性和计算结果的准确性,为进一步分析电力电缆系统的磁、热特性奠定了基础.
建立瞭多導體電力電纜置于具有散熱孔的託架上時3D有限元時諧磁場模型,在計及各金屬渦流效應的條件下,得到所有導體單元的功率損耗密度.以此功率體密度損耗為栽荷,建立瞭電纜繫統的"熱-流體"直接耦閤場模型,求解瞭電纜繫統各導體的溫升,由此完成一次完整的"磁場"與"熱-流體"場間接耦捨的求解.由于電纜導體電阻率與溫度密切相關,形成"磁場"與"熱-流體"場間接耦閤的雙嚮耦閤.反複迭代,可求解得到噹熱點為90℃時導體的電流,即為電纜的載流量.以無鎧裝單載流和有鎧裝三併聯栽流電纜為例,採用間接耦閤法計算和測量瞭繫統的總功率、電流分佈、導體熱點溫度.計算和測量一緻性說明瞭雙嚮間接耦閤有限元模型建立的正確性和計算結果的準確性,為進一步分析電力電纜繫統的磁、熱特性奠定瞭基礎.
건립료다도체전력전람치우구유산열공적탁가상시3D유한원시해자장모형,재계급각금속와류효응적조건하,득도소유도체단원적공솔손모밀도.이차공솔체밀도손모위재하,건립료전람계통적"열-류체"직접우합장모형,구해료전람계통각도체적온승,유차완성일차완정적"자장"여"열-류체"장간접우사적구해.유우전람도체전조솔여온도밀절상관,형성"자장"여"열-류체"장간접우합적쌍향우합.반복질대,가구해득도당열점위90℃시도체적전류,즉위전람적재류량.이무개장단재류화유개장삼병련재류전람위례,채용간접우합법계산화측량료계통적총공솔、전류분포、도체열점온도.계산화측량일치성설명료쌍향간접우합유한원모형건립적정학성화계산결과적준학성,위진일보분석전력전람계통적자、열특성전정료기출.
A 3-D finite element harmonic field model of multi-conductor power cables placed on a perforated metal tray is established. Power loss densities of all metallic elements with the skin effect are obtained. By taking the power densities as a load, the direct thermal-fluid coupled model of the cable system is set up and temperature rises are calculated. Therefore, the magnetic field and the thermal-fluid field indirect coupled solution for the cable system is achieved. Beeause the conductor resistivity is affected by its temperature, the coupled model of the cable system becomes a bi-indirect coupled model between the magnetic field and the thermal-fluid field. Using an iterative procedure, the ampaeity of the cable system can be solved with a high temperature 90℃. Using the examples of a non-armored cable with the single current and an armored cable with the mode of three-parallel cable, the total power losses, the hottest point temperature of conductors and the current distributions are calculated and tested by the indirect coupled method. The match of calculated and tested results illustrates that the bidirectional indirect coupled model is valid and accurate. And it can be used for analyzing magnetic and thermal properties of power cable systems.