Paper Machine Dryer Section Tuning: A Novel Solution to Prevent System Instability

Paper machine dryer sect ions create challenges in tuning due to gear backlash. This problem is amplified when older paper machines are upgraded with newer, higher-performance drive systems. The newer drive systems can achieve a much higher degree of control, which can fatigue the mechanical drivetrain. Most often, backlash is experienced during the speed regulator tune-up [1]. The speed regulator response is modified in an effort to improve stability while in backlash. However, there are other tune-up considerations that must be considered. A dryer section can be pulled from a downstream section, which can cause its applied torque to be near zero, resulting in speed instability. This article investigates the cause of this instability and presents a novel solution for preventing it.