中低压柜防涡流的措施有哪些呢？

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好吧，我们阶段性总结一下，再讨论：
1.单相载流导体穿过闭合导磁材料构成的回路会引起涡流和磁滞损耗，也即发热；
2.三相载流导体同时穿过闭合导磁材料构成的回路会不会引起涡流和磁滞损耗呢？
对于第2点，我觉得要考虑如下方面：
2.1 三相导体流过电流是否平衡；
2.2 三相导体的空间布置如何，平行布置还是等边三角形布置；
2.3 导磁材料构成的回路环大小有影响吗? 无穷大的闭环回路不考虑；

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治学以诚 发表于 2016-4-15 14:05
因为这个问题非常深刻，你不要嫌啰嗦。我们一点一点纵横捭阖。

1946年国际计量委员会通过了安培定义的决 ...

电动力是电流与电流之间的作用，假如短路情况下三相导体流过的短路电流为100KA,导体间的电动力与相间距、绝缘子间距有关系，还与100*100kA成正比，而此时如果按诚版所言考虑载流导体（例如A相）与骨架内电流之间的电动力，试问此时骨架内的感应电流能有多大呢，会有100kA吗？截图是计算母排间电动力的公式，中、低压开关的主母线动稳定校核就是依据该公式：

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治学以诚 发表于 2016-4-15 14:14

这根不锈钢不是考虑垂直母线加的，是考虑主母排电流流向，见图：

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母线夹的作用就是抵御短路情况下短路电流作用在母排上的电动力，在导体相间距确定的情况下，母线夹的数量和间距是依据柜体Icw确定的，不同的Icw对应不同数量，即母线夹间距也确定了。

Tricity

有一本书说得比较清楚，节选了一小部分：

Proximity effect on the enclosure
The electric field produced by the current-carrying conductors of each phase also links the metallic bus
enclosure, its mounting supports, and structures existing in the vicinity, parallel and around the axis of the current-
carrying conductors. It causes induced (parasitic) currents in such structures and leads to the following:

Resistance losses (I2R) and
Magnetic losses.

Magnetic losses will constitute the following:
Eddy current losses and
Hysteresis losses

The electrodynamic forces between the enclosure and the conductors will be small because the enclosure, which
is non-continuous, will carry much less current than the main conductors. They therefore need not be considered
separately, as the metallic structure will have sufficient strength to bear them.
In a non-magnetic enclosure, such as aluminium or stainless steel, there will be only resistance losses. In a
magnetic enclosure, such as mild steel (MS), there will also be hysteresis and eddy current losses in addition to
resistance losses. All these losses appear as heat in the enclosure and the metallic structures in the vicinity. At
higher currents say, 2000 A and above, this phenomena, particularly with MS enclosures, may assume such large
proportions that the enclosure, instead of providing aheat-dissipating surface to the heat generated by the
current-carrying conductors inside, may add to their heat.

Tricity

变压器铁芯采用硅钢片，目的是增大电阻率，降低涡流损耗。

1. 采用低磁或非磁性材料，降低或消除磁滞损耗。
2. 采用电阻率高的材料，降低涡流损耗。

不锈钢同时符合上述两个条件。

楼上数次说不锈钢发热会更厉害，理论建立在涡流大小一样的前提下。您能保证不同的材料在同样强度的磁场下，感应出的涡流是一样大的？

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中低压开关柜上用的不锈钢都是无磁性的304奥氏体不锈钢，不是导磁性的铁素体或马氏体不锈钢，后者在家用场合常见，不适合中低压开关柜上使用。