针对基于Petri网的离散事件系统禁止状态问题,提出了一种控制器综合方法.该方法是建立在受控Petri网最大不可控子网为规范化序状Petri网基础之上的,当禁止状态有限时,可以将禁止状态问题转化为惟一可达解向量问题,即可达标识和状态方程的解向量之间存在惟一的对应关系,从而只须通过判断惟一可达解向量就能够得到相应的控制器.通过一个具体的例子验证了该方法在设计最大允许控制器中的应用,例证表明,针对有限禁止状态问题,该方法是可行的,并且简单、有效.
A controller synthesis method was proposed for discrete event systems modeled by Petri net on finite forbidden state problem. The method can be used to design maximally permissive controllers when maximal uncontrolled subnets have some normalized cascade structures. If the forbidden states are finite, the problem can be transformed into an only reachability problem, that is to say, a reachable marking can be decided by solving the state equation and the solution is unique. Therefore, the maximally permissive controller can be obtained by solving the state equation. An example was illustrated to verify the method for designing the maximally permissive controller. The results showed that the method is feasible, simple and efficient to deal with the forbidden state problem.