ペトリネットによるシーケンス制御システムの故障診断と運転継続

抄録

In a factory automation, sequential control is one of the most important tequniques. In a sequential control system, the simulation of control program and the fault diagnosis of machine are very useful. In particular, for fault diagnosis, we must consider not only quick detection of fault parts but also continuation of operation. This is fault-tolerant technique. The achivement of high availability of a controlled system is important.
We reserch a useful fault diagnosis method of sequential control system. First, we construct Petri nets for control and controlled system, and simulate the movement of sequential control system with the Petri nets. Next, using the simulation model with Petri net, we carry out the fault diagnosis of the real sequential control system. For input signal of Petri nets for control, we use two input signals transmitted from Petri nets for controlled system and from real controlled system. Thus, by being duplication of input signal of Petri nets for control, this fault diagnosis method have so advantages as prevention of fault spread and fault-tolerance.
In this paper, we describe the new fault diagnosis method of sequential control systems, the realization of fault-tolerance with Petri net and the simulation of the sequential control system using the method of a vehicle moving between the yards in a factory.