高压交流海缆电气参数对线路对称性的影响  

Influence of Electrical Parameters of High Voltage AC Submarine Cables on Characteristic of Symmetry of the Grid-link Line

作　　者：朱志芳[1] 

机构地区：[1]广东省电力设计研究院,广州510600

出　　处：《高电压技术》2007年第6期177-179,共3页High Voltage Engineering

摘　　要：海南电网拟通过单回500kV交流线路与广东电网实现互联,联网线路采用的海底电缆不实施换位引起的相间差异即为线路不对称的根源,故需要明确海缆段参数是否需要补偿及其对整条线路换位塔塔位确立的影响。为此,根据海缆结构及其在海底分布间距的特点,分析了海缆段三相工作电阻和电容的对称性问题,并结合电缆所交链的内外磁链特性计算了海缆三相工作电感值及其两两差值;根据架空线路各相导线所交链的磁链原理推导了架空段线路三相工作电感值及其两两差值。比较海缆段与架空段工作电感值可知,均不换位且分别等间距水平布置下海缆与架空线单位长度三相电感的两两差值对应相等,因此设计联网线路整循环换位时,海缆段等同于架空线路段考虑,不需补偿海缆段参数的不平衡。The characteristic of symmetry of the values of cables＇ three-phase working resistance and capacitance are simply analyzed for the project of Hainan power system linking to Guangdong power system by single loop 500kV AC transmission line, the three-phase working inductance values and their difference between one phase and another are calculated according to the characteristic of their internal and external magnetic flux linkage. The same work of overhead lines is done according to the magnetic flux linkage principle of each phase conductor. From these analyses we can draw conclusions that the values of cables＇ three-phase working resistance and capacitance are symmetrical respectively, and the phase-to-phase working inductance difference of cables and overhead lines are equal correspondingly. So we can easily eliminate the dissymmetry of three-phase inductance parameters of the grid-link line by cycle transposition without additional compensations.

关 键 词：海底电缆 架空线 对称性 工作电感 循环换位 不平衡 

分 类 号：TM248[一般工业技术—材料科学与工程]