高压侧选择两根3×185mm^2的三芯交联聚乙烯绝缘船用电缆,计算过程如下:--------------------------------------------------------------------------------Transformer 4000 kVA, 3 phase, 4160VFull Load Current (FLC) is3 Phase KVA=(Volts×Amps×√3)/1000
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Transformer 4000 kVA, 3 phase, 4160V
Full Load Current (FLC) is
3 Phase KVA=(Volts×Amps×√3)/1000
I=(3 Phase KVA×1000)/(Volts×√3)=(4000×1000)/(4160×1.732)=555A
Wire Size =555×125%=693.75A
(对于支路电缆允许载流量不小于回路电流的125%,对于变压器的主回路是否也有这样的要求?)
Per Table 310.71 (Temperatures of 90°C), the conductor must be 2×350kcmil or 2×185〖mm〗^2
Insulated Three-Conductor Copper Cable rated 2×395=790A
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低压侧选择27根300mm^2的单芯交联聚乙烯绝缘船用电缆(每相9根),计算过程如下:
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Transformer 4000 kVA, 3 phase, 600V
Full Load Current (FLC) is
3 Phase KVA=(Volts×Amps×√3)/1000
I=(3 Phase KVA×1000)/(Volts×√3)=(4000×1000)/(600×1.732)=3849A
Ambient Temp. is 40°C, Correction Factor is 0.82
Wire Size = (3849×125%)/0.82=5867A
(对于支路电缆允许载流量不小于回路电流的125%,对于变压器的主回路是否也有这样的要求?)
Per Table 310.16 (75°C terminals [110.14(C)(1)(b)]), the conductor must be 9×600kcmil or 9×300〖mm〗^2
Insulated Single Conductor Copper Cable rated 9×690=6210A
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麻烦帮我看看计算过程是否正确?
对于支路,导体的载流量要大于负载最大电流的1.25倍。
变压器输入输出端对导体载流量有什么要求?
变压器的输出端接在开关柜中的一个2500A的主断路器,请问计算导体的载流量应该按变压器的最大输出电流计算还是按照负载的主断路器的额定电流计算?
[ 本帖最后由 zyz8438 于 2011-5-8 19:07 编辑 ]