[Abstract] This paper addresses the issue of converting high-failure-rate DC drive control to AC drive control, exploring the necessity and applicability of AC frequency conversion, and also raises issues that should be considered during application. [Keywords] AC frequency converter, rubber blanket, wool blanket, traction roller, drive, shrinkage controller 1. Problem Statement The problem of dimensional variation in natural fabrics has always been one of the difficulties in the textile printing and dyeing industry. To solve this problem, rubber blanket pre-shrinking equipment is now widely used. Our finishing workshop uses an imported American Merison pre-shrinking machine. The electrical control of this equipment mainly adopts PLC control and DC speed regulation drive. It is divided into rubber blanket drive, wool blanket drive, and traction roller drive. Currently, due to its age, unstable speed, abnormal shrinkage, and sometimes unexplained stops occur during production, resulting in a large number of defective fabrics. Reasons: The commutator of the rubber blanket DC motor is worn out; the wool blanket DC motor drive has an AC component, and purchasing original DC motors is expensive and has a long procurement cycle. In order to ensure production, the electrical control part of the equipment was converted to AC frequency conversion speed regulation, which has a good effect. [b]2. Variable Frequency Drive Retrofit 2.1 System Hardware The rubber blanket, felt blanket, and traction roller motors are selected as 15KW, 2.2KW, and 2.2KW AC variable frequency motors respectively; the frequency converters selected are the high-performance vector control variable frequency speed controllers TD3000 and TD2000 from Emerson Network Power Co., Ltd. [b][align=center]For details, please click: Application of Variable Frequency Technology in Merison Pre-shrinkage Machines[/align][/b]