varying frequency

• 变频

varying frequency的用法和样例：

例句

1. The main pump uses frequency conversion control.
   主泵采用变频控制。
2. A twist wire connected with multicircuit or variable frequency circuit board is winded on the industrial pipeline.
   远处有多匝与变频电路板连接的螺旋状电线缠绕在工业管道上。