The thesis is directed by the idea of oriented-object. Considering the basic functions that NC system Ladder Diagram editor should provide,and through theoretical research and practice,the thesis developed a set of NC...The thesis is directed by the idea of oriented-object. Considering the basic functions that NC system Ladder Diagram editor should provide,and through theoretical research and practice,the thesis developed a set of NC system Ladder Diagram editor which can form a Ladder Diagram editor based on vector plotting,intelligently compiling,simulation. This system uses the ladder diagram symbol to express operational order and use the chart symbol series-parallel connection and the position order to express the logical relations between the operational orders,divide the ladder diagram into four parts: the stave,the line,the row and the part,uses the standard order vessel list vessel of the standard template stack (STL) to save the data which involved in the design process. This system can write PLC program by ladder diagram language and is easy to use. The compilation and simulation for PLC diagram have been achieved. It greatly improves the work-efficiency.展开更多
An approach to design and implement the control function of LD (Ladder Diagram) in the hydropower simulation system based on all paths searching algorithm is proposed in this paper. LD is widely used as a programming ...An approach to design and implement the control function of LD (Ladder Diagram) in the hydropower simulation system based on all paths searching algorithm is proposed in this paper. LD is widely used as a programming language for PLC (Programmable Logic Controller), but it doesn’t be executed automatically in the hydropower simulation system which is a software system, and there is no compiler or interpretation for LD in it. The approach in this paper is not only to present a graphical interface to design LD, but also implement its control function through transforming it to a corresponding undigraph, in which, all paths be-tween two vertexes (live wire and null line) are searched by the proposed algorithm. An application example is presented to verify the validity of the algorithm and shows that the algorithm is correct and practicable. In addition, how to implement the control function based on object-oriented thought is introduced. The running time is shown at last, which proves that the system with the algorithm can meet the real-time request in the hydropower simulation system.展开更多
文摘The thesis is directed by the idea of oriented-object. Considering the basic functions that NC system Ladder Diagram editor should provide,and through theoretical research and practice,the thesis developed a set of NC system Ladder Diagram editor which can form a Ladder Diagram editor based on vector plotting,intelligently compiling,simulation. This system uses the ladder diagram symbol to express operational order and use the chart symbol series-parallel connection and the position order to express the logical relations between the operational orders,divide the ladder diagram into four parts: the stave,the line,the row and the part,uses the standard order vessel list vessel of the standard template stack (STL) to save the data which involved in the design process. This system can write PLC program by ladder diagram language and is easy to use. The compilation and simulation for PLC diagram have been achieved. It greatly improves the work-efficiency.
文摘An approach to design and implement the control function of LD (Ladder Diagram) in the hydropower simulation system based on all paths searching algorithm is proposed in this paper. LD is widely used as a programming language for PLC (Programmable Logic Controller), but it doesn’t be executed automatically in the hydropower simulation system which is a software system, and there is no compiler or interpretation for LD in it. The approach in this paper is not only to present a graphical interface to design LD, but also implement its control function through transforming it to a corresponding undigraph, in which, all paths be-tween two vertexes (live wire and null line) are searched by the proposed algorithm. An application example is presented to verify the validity of the algorithm and shows that the algorithm is correct and practicable. In addition, how to implement the control function based on object-oriented thought is introduced. The running time is shown at last, which proves that the system with the algorithm can meet the real-time request in the hydropower simulation system.
