A novel Modbus RTU-based communication system for adjustable speed drives

The communication protocol is important for applying adjustable speed drive (ASD) systems to an industry network. This paper proposes a novel scheme of communication system for the ASD system based on Modbus protocol. The most remarkable advantage of the approach lies in the tradeoff between performance and economic cost for a power converter system. The overall system is built on master-slave structure and easy for interacting with other networks. An additional study on the cyclic redundancy check (CRC) in Modbus RTU is introduced to obtain the optimization design in the actual application and the optimization method in software design is also presented. The performance of the communication system obtained from experiment conducted on the 15 kW ASD system validates the effectiveness of the proposed design method.