Self-Balancing Control of Yarn Number Based on a Novel Sensorless PMSM Speed Drive System

The performance of the motor drive system is responsible for the yarn feeding quality of the weft accumulator. The existing motor drive systems have problems such as slow start–stop and poor dynamic response performance, resulting in slow yarn tracking speed and low precision of the weft accumulator. This article proposes a new self-balancing yarn number control method based on a novel sensorless permanent magnet synchronous motor (PMSM) speed drive system. The novel sensorless PMSM speed drive system is constructed to improve the dynamic response performance of PMSM by integrating an improved sliding mode observer, a simplified initial position detection method, and a new hybrid control method. The self-balancing yarn number closed-loop control method is proposed based on a pseudoderivative feedback controller to improve the response speed and accuracy of yarn feeding. The general design principle is given, and various tests are carried out. The results show that the proposed drive system has characteristics of a fast start–stop and high dynamic response, which can meet the high-response and high-precision yarn feeding requirements of the weft accumulator.