In this system, the rotary cutting machine is driven by the D51 frequency converter, the wiring of the control system is simple, no external controller is needed, all functions are realized by the built-in frequency converter, and the whole system is economical and reliable. Using the rotary encoder as the distance measuring sensor can improve the measurement accuracy to 0.01mm; using the rotary encoder to measure the actual speed of the roller can avoid the error caused by the unstable grid voltage on the thickness of the rotary cutting.