【简答题】简单电力系统如题图所示,各元件参数如下。 发电机G:P N =250MW,COSφ N =0.85,V N =10.5kV,x d =1.7,x' d =0.25,T J =8S; 变压器T-1:S N =300MV·A,V S %=15,k T =10.5/242; 变压器T-2:S N =300MV·A,V S %=15,k T =220/121; 线路L:l=250km,V N =220kV...
【简答题】已知图10中 I1=4A,I2=2A, I3=-2A,其他参数及参考方向如图所示。____试求元件两端电压Ux,并确定电路元件x是电源还是负载;____两个电阻上消耗的功率 第11题: V X =R 1 I 1 +E 1 =50V; Px=V 3 I 3 =-100WL 0 ; X是负载充电 P E =E 1 I 1 =400W____
【简答题】Joe Smith has left a voice message for Lily. Listen for the message and fill in theblanks with what you hear. Lily, this is Joe Smith. Please reserve a seven day Yunnan highlight tour for 21 tourists,...
【简答题】Please translate the following letter into English. You are supposed to supply some necessary information such as the name, address and telephone number of a corporation..., etc. on your own as reques...
【简答题】Case One Dear Mr. Smith , (从我国驻贵国商务参赞处得知贵公司的名称和地址) as the leading importer of light industrial products in your country. We now . (利用此次机会给你方写信了解我方是否可以与你方建业业务关系 . , (为使你方了解我们经营的轻工业产品) , we are airmaili...