摘要
提出了利用自由通信协议,以PLC作为主站,通过RS-485总线与多台变频器串行通信构成的变频同步控制系统。介绍了系统的硬件构成,根据PLC与变频器之间的通信原理和通信协议,对于速度的设定,采用了定时中断发送数据的方式,实现了线速度的同步;而对于电机的启动和停止,则可采用广播方式或单独发送方式;最后给出了系统的软件流程图。实践表明,该同步控制系统与传统同步控制系统相比具有速度控制灵活、准确和可靠性高等优点。
A variable frequency synchronous control system based on free communication protocol is presented. As the master station, the PLC is communicated with multi-inverters through RS-485 serial bus. The hardware structure of system is introduced. For speed setup, based on the communication principle and communication protocol between PLC and the inverters , the mode of timing interrupt data sending is adopted to realize synchronization of line speed. For startup and stop of the motors, the mode of broadcasting or sending data separately is used. Finally the software flowchart of the system is given. Compared with traditional synchronous control system, the design features the advantages of flexible, accurate and reliable speed control.
出处
《自动化仪表》
CAS
2007年第8期65-66,69,共3页
Process Automation Instrumentation
