Abstract : This paper addresses the high failure rate, inconvenient use and maintenance, and heavy workload caused by the numerous tensioner synchronization control devices in traditional multi-motor drive systems of papermaking, textile, and printing and dyeing machinery, which seriously affect production. The principle and method of variable frequency speed control synchronization are studied, and a novel multi-motor synchronous speed control scheme is researched and designed, using a computer to control the frequency converter via an RS-485 control bus. This scheme eliminates the need for tensioners or tension sensors, greatly simplifying the synchronous actuation control system structure, significantly reducing equipment costs, and greatly improving system reliability and control management level. Furthermore, it saves energy and reduces consumption, increasing product output, quality, and the economic efficiency of equipment operation. Keywords : Computer control; Frequency converter; Control bus; Multi-motor synchronization; Tension control Introduction Compared to DC speed control systems, AC variable frequency speed control systems have significant advantages such as light weight, small size, and simple and convenient use and maintenance, and possess good dynamic and static characteristics similar to DC speed control systems, they have begun to replace DC speed control systems. With the maturation of integrated circuit and power device manufacturing technologies and the continuous decline in costs, variable frequency speed control technology has begun to be widely used in industries such as papermaking, textiles, and dyeing. The extensive use of frequency converters in fans and air conditioners has resulted in energy savings of up to 40%. The application of frequency conversion speed control in textile machinery has improved equipment speed and speed control accuracy, leading to a significant increase in product output and quality. In the continuous processing of textiles in textile or dyeing combined machines, each processing unit's drive roller is driven by a separate motor. Because the material input and output speeds of each unit must be consistent, the multi-unit electrical drive system must operate synchronously and in coordination. This requirement is widespread, as seen in papermaking processes and multi-stage conveyor belts, and it represents a key problem that needs to be solved. Combining network technology, computer control technology, and frequency conversion technology in multi-motor synchronous control can fully leverage their significant advantages, improving the control and management level of multi-motor synchronous systems and the economic efficiency of equipment operation. 1. Multi-motor Synchronous Drive System A typical multi-unit motor synchronous drive system for continuous processing machinery is shown in Figure 1. M is the master unit motor, and the others are driven unit motors. During the continuous processing of materials, the linear speed of each unit must be kept synchronized according to the relationship in equation (1) to meet different process requirements. [b][align=center]For more details, please click: Application of Computers in New Multi-Motor Synchronous Systems[/align][/b]