The Research Of The Central Heating Control System Based On LonWorks Fieldbus

With the gradual strengthening of the human energy-saving, traditional decentralized heating system has been replaced by the central heating system, which helps save energy, reduce pollution and improve living standards. In the central heating system, heating substation is an intermediate point between heat source and heating users. Heating quality of the station is important to improve working condition of heating network and heating quality.With the development of computer control technology and improving communication technology, traditional DCS distributed control system for heating can not meet the demand of the central heating control system, for the questions exciting in it such as poor interchangeability and low reliability, but LonWorks Fieldbus provides a solid solution to the above problems with its characteristics as an open and interoperable system. Based on this point, the paper designs the intelligent node of the central heating control system based on LonWorks Fieldbus.Firstly the paper introduces the two core technology of LonWorks Fieldbus which is based on Neuron chips and the LonTalk protocol, and combines with the working principle of the centralized heating substation, designing the heating substation monitor system based on LonWorks.Then the temperature-controlled algorithm of the heating substation is studied. Traditional PID control algorithm can not achieve good control effect for the heating system with large inertia, time-delay and parameter-varying, so designing a Smith and fuzzy self-adaptive PID controller, which the fuzzy self-adaptive PID controller achieves the function of real-time adjustment of the PID three parameters, and the introduction of Smith predictor compensator can be a better solution to the dynamic time-delay problem of the heating system, finally carrying through simulating research.At last, the hardware and software of the intelligent node of the system are designed.The node adopts the nodal type based on host processor. The Low-power MSP430F149 microprocessor is adopted as host processor, which is responsible for gathering and dealing with the operating parameters of the heating substation, and TP/FT-10F flash control module which takes Neuron chip as the core is used as the communication processor, it solves the communication problems between microcomputer and LonWorks network and achieves the node control function.