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使用变频器时,电机温升为什么比工频时高?

更新时间:2024-04-18 16:01:43
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正确答案:

因为变频器输出电压波形不是正弦波,而是畸形波,在额定扭矩下的电机电流比工频时要多出约 10%左右,所以温升比工频时略有提高。另外还有一点:当电机转速降低的时候,电机散热风扇速度不够,电机温升会高一些。

答案解析:

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