A lathe is a machine tool that mainly uses a turning tool to turn a rotating workpiece. Drills, reamers, reamers, taps, dies and knurling tools can also be used on the lathe for corresponding processing. Due to the traditional power frequency processing technology, it is impossible to carry out precise speed regulation according to the processing material, long power frequency shutdown time, heavy start-up equipment impact, high failure rate and other unfavorable factors, so the frequency conversion speed regulation is adopted, which has a good application space.