Active compliance control of grinding process for stripping enameled copper wire

The hairpin motor, increasingly utilized in eco-friendly vehicles, incorporates enamel-coated coils with a square cross-section. This motor offers improved power by achieving a higher coil fill factor, which significantly enhances efficiency. As the production of hairpin motors becomes more automated, the enamel removal process has become a critical focus for ensuring high-quality and high-performance outcomes. Residual enamel on the coils can lead to problems in the welding process, potentially degrading the performance of the motor. Furthermore, excessive loss of internal copper during machining can adversely affect the overall motor output, leading to decreased performance and efficiency. In this study, an adaptive control algorithm was developed to address these challenges by optimizing the grinding process for enamel removal. This advanced system monitors spindle torque in real time to accurately calculate the grinding force applied during machining. Experimental tests of this system have demonstrated a notable improvement, reducing copper loss from 19 to just 7%. The study also investigated how varying conditions of the grinding wheel influence the grinding force ratio. The analysis indicates that an algorithm could be developed to monitor this ratio effectively, allowing for timely replacement or dressing of the grinding tool. Such advancements are expected to enhance overall production efficiency and motor performance.