Constant wire tension control using fuzzy method in multi-wire saw machine

Constant wire tension is one of the key requirements to achieve high wafer quality in multi-wire saw machine. For the constant wire tension control, the wire tension analysis is firstly derived based on the torque equilibrium of the motor in the tension arm and the wire length variation. Then a closed-loop wire tension control strategy is designed based on fuzzy method due to its complicated nonlinearity. In the controller, the tension arm angle is considered as the feedback variable, and the angular velocity of the sending reel is selected as the controlled variable. Experimental results are demonstrated to verify the effectiveness of the proposed control methods in this paper.