问题 单项选择题

某220kV变电站位于Ⅲ级污秽区,海拔高度600m,220kV2回电源进线,2回负荷出线,每回出线各带负荷120MVA,采用单母线分段接线,2台电压等级为220/110/10kV,容量为240MVA主变,负载率为65%,母线采用管形铝镁合金,户外布置。220kV电源进线配置了变比为2000/5A电流互感器,其主保护动作时间为0.1s,后备保护动作时间为2s,断路器全分闸时间为40ms,最大运行方式时,220kV母线三相短路电流为30kA,站用变压器容量为2台400kVA。请回答下列问题。

请计算该站用于站用变压器保护的高压熔断器熔体的额定电流,判断下列哪项是正确的,并说明理由。(系数取1.3)()

A.熔管25A,熔体30A

B.熔管50A,熔体30A

C.熔管30A,熔体32A

D.熔管50A,熔体32A

答案

参考答案:D

完形填空
Last night I was driving from Harrisburg to Lewisburg, a distance of about 80 miles. It was late, and I was driving          .
At one point along an open highway, I came to a crossroad with a traffic light. I was         on the road by now, but as I came near the light, it turned         , and I braked to a stop. I looked left, right, and behind me. Nothing. No car, no suggestion of headlights,          there I sat, waiting for the light to        , the only human being, for at least a mile in any       .
I started wondering why I         to run the light. I was not afraid of being caught, because there was         no policeman anywhere around and there certainly would have been no         in going through it.
Much later that        , after I'd met with a group in Lewisburg and had climbed into bed near midnight, the question of why I'd stopped for that light         me. I think I stopped         it's part of a contract(契约) we all have with each other. It's not only the law, but it's an agreement we have, and we trust each other to follow          : we don't go through red lights.
We do          we say we'll do. We show up when we say we'll show up.
I was so        of myself for stopping for that red light. And as no one would ever have known what a good person I was on the road from Harrisburg to Lewisburg, I had to tell someone.
小题1:
A.fastB.slowlyC.carefullyD.hard
小题2:
A.lateB.aloneC.worriedD.afraid
小题3:
A.greenB.yellowC.redD.dark
小题4:
A.andB.orC.soD.but
小题5:
A.returnB.changeC.startD.continue
小题6:
A.attentionB.backgroundC.directionD.information
小题7:
A.refusedB.decidedC.preparedD.forgot
小题8:
A.hardlyB.luckilyC.usuallyD.clearly
小题9:
A.dangerB.excuseC.spaceD.energy
小题10:
A.momentB.nightC.afternoonD.morning
小题11:
A.depended onB.looked forward toC.stayed away fromD.came back to
小题12:
A.thoughB.unlessC.becauseD.until
小题13:
A.meB.itC.himD.us
小题14:
A.whatB.howC.whyD.that
小题15:
A.tiredB.readyC.proudD.sorry
选择题