Research And Application Of Central Heating Control Systems

Up till now, technique levels of the whole heating industry in our country falls behind the others. The low combustion ratio and the insufficiency burning of boilers in heat providing lead to grievous air pollution. It is an urgent to improve the boiler technique. City area heating mode is now wild used to improve the heat efficiency.As the rapid development of modern society, more efficiency city area heating systems are requested. It is a problem to be solved desperately, that using computer control system in heat providing process to make the boiler a stable and continuous heating resource, also to realize the long-distance controlling and real-time monitoring of the heat demands in producing and living process, and meet the demands of energy saving and environmental protection.The city area heating system is made of two parts, the automatic control system of a boiler and the adjustment system of heating net. These two parts have many characters respect and also many comments. The data processors of each system are the same. Dates collected by thermal meter in worksite are sent to the mean computer to do some analyses and then the orders are distributed to the execute setup. The key points are the burning control of the boiler self-control system and the long-distance date transmission of the heat netIn this work, the output water temperature of the boilers is set as the variable quantity. At the boiler grate, using a composite fuzzy PID (proportional integral differential) controller which has combined the fuzzy control method with the classic PID control method to adjust water temperature, resolved the contradiction between the variation of outside temperature and the real-time adjustment of boilers combusting and realized heat providing on demand.In this work, we also studied the controlling for liquid level in the steam drum of the boiler. The mechanism of three-impulse regulation system, together with the application and the function condition of this system are discussed. The GPRS technique is applied in the management system of heat net. The results show this method is efficient in the real applications.According to the requirement of the working condition, the Sims'PLC method is appalled in the key problem of the city area heating systems. Firstly, the GPRS technique applied in the heat net is analysis and designed in detail. Secondly, the parameter determination and set-up procession is gived. Furthermore, three-impulse regulation method is applied for liquid level in the steam drum of the boiler, and a composite fuzzy PID (proportional integral differential) controller which has combined the fuzzy control with the classic PID control is applied for boilers combusting. At the same time, the method of controlling combusting used by controlling the oxygen content of the smoke is discussed. .