更新时间2019-07-07 17:50:16
将电源移至 1、1';
从左向右,6Ω电阻两端 a1、a2 等效电阻 Ra = 9//6 = 9 * 6/(9+6) = 18/5Ω ;
5Ω电阻两端 b1、b2 等效电阻 Rb = (Ra+7)//5 = (53/5) * 5/(53/5+5) = 265/78Ω;
Ub = 5 * Rb/(Rb+2) = 5 * (265/78)/( 265/78 + 2 ) = 1325/421 v;
Ua = Ub * Ra/(Ra+7) = (1325/421) * (18/5)/(18/5+7) = 450/421 v;
9Ω电阻电流 I = Ua/9 = 50/421 A;
由互易定理,电源在左侧,则 Isc = I = 50/421 A;
电源短路,1、1' 端等效电阻 r = (Rb+2)//10
= (265/78+2)//10 = (421/78) * 10/(421/78+10) = 4210/1201 Ω;
Uoc = Isc * r = (50/421) * (4210/1201) = 500/1201 v 。