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【单选题】
某125MW火电机组低压厂变回路从6kV厂用工作段母线引接，该母线短路电流周期分量起始值为28kA。低压厂变为油浸自三相变压器，参数为：Se=1000kVA，Ue=6.3/0.4kV，阻抗电压Ud=4.5%，接线组别Dynll，额定负载的负载损耗Pd=10kW。DLi为6kV真空断路器，开断时间为60ms；DL2为0.4kV空气断路器。该变压器高压侧至6kV开关柜用电缆连接；低压侧至0.4kV开关柜用硬导体连接，该段硬导体每相阻抗为Zm=（0.15+j0.4）mΩ；中性点直接接地。低压厂变设主保护和后备保护，主保护动作时间为20ms，后备保护动作时间为300ms。低压厂变回路接线及布置如图3-3所示，请解答下列各小题（计算题按最接近数值选项）。下列变压器保护配置方案符合规程的为哪项？为什么？（）A.
电流速断+瓦斯+过电流+单相接地+温度
B.
纵联差动+电流速断+瓦斯+过电流+单相接地
C.
电流速断+过电流+单相接地+温度
D.
电流速断+瓦斯+过电流+单相接地
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举一反三
【简答题】平行登记的要点不包括（ ）。
【单选题】The young for growing independence while the elder want their son or daughter to listen to them.
A.
tended to ask
B.
tends asking
C.
tend to ask
D.
tend toward asking
【单选题】Listen, TED ______________
A.
started in 1994 as a conferece.
B.
became a non-profit after it was acquired.
C.
went public in 2001
D.
initially had a different name.
【简答题】A．They need to listen to their kids with great interest and attention. B．They should tell whether it's their kids mistake. C．They should exchange all their life stories with the kids. D．They should gi...
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