adjusting speed by variable frequency的用法和样例：
- Based on the actuality that in China's printing industry equipment,the main drive mostly adjusts speed by variable frequency,but less usage in itss auxiliary function.
- variable frequency adjusting speed
- Based on the systematical discussion of character mechanical drive,baric drive,adjusting speed by changing frequency,sensor and PLC,the hardware design and composion are finished.
- In this paper the ultrafine of attapulgite from Xuyi was studied by variable frequency planet-type grinding mill.