A microprocessor-based duplex fault-tolerant controller for industrial process control

Reliability is one of the fundamental considerations in the design of industrial control equipment. The microprocessor-based hybrid duplex fault-tolerant system (HDS) proposed in this paper has high reliability to meet this demand although its hardware structure is simple. The hardware configuration of HDS and the fault tolerance of this system are described. The switching control strategies in HDS are studied in detail. Disputes between two subsystems are avoided due to the highly modular structure and the efficient fault detection. Reliability estimation methods for this system are also developed. The implementation of fault tolerance in HDS is software intensive. This system is specially designed for industrial process control.