Abstract: To address the issue of transformer magnetic flux leakage and optimize the magnetic shielding effect, an automated control system for a lung-shaped straight shear machine has been designed, specifically for processing lung-shaped silicon steel sheets for transformer cores. The selected control core is a PLC, supplemented by a HMI (Human-Machine Interface) and several servo systems. An industrial bus is used to build a distributed control network, which effectively achieves automation of various functions such as automatic feeding, punching, bevel cutting, right-angle cutting, and material collection of silicon steel sheets. Based on the lung-shaped calculation method using geometric equation iteration, the system first solves for the coordinates of the intersection points of multiple circles and straight lines, chord lengths, and arc lengths, and then accurately calculates the processing length of each silicon steel sheet. The system can also flexibly adapt to the production needs of lung-shaped cores of different specifications.