Abstract: Traditional synchronous control systems in multi-drive dyeing and printing machines have too many drawing frames,which leads to frequent malfunction,effort-taking operation and painstaking maintenance.The article probes into principles for a solution to these problems and presents a design for a multi-drive synchronization speed control system with no or fewer drawing frames and tension sensors.The system is based on frequency conversion and computer network technologies.Its digital control over multi-drive speed regulation simplifies the synchronization system and provides higher reliability and stability.In the actual design of such a system,the IPC controls the frequency inverter via RS-485 bus in replace of the traditional DC speed-control system with multi-drive control system.The smooth operation proves that this system is successful and effective.