| Centralized heating is an important matter in the north China. Centralized heating systems implemented in large-scale mode could rise modernization level of city and save energy, as well as to improve atmosphere environment. The traditional heating systems, such as two-upright-pipe parallel systems, two-pipe systems, and single-pipe stride systems, etc, are commonly used in our municipal. Actually, the single-pipe stride systems are most common. In these systems, heating fee is accounted based on the building area heated, rather than in the way of how much calories that the customers used. Also, it could not take consideration of customer need for heat. Therefore, the indoor temperatures in different dwelling districts are quite different. Sometimes, the room temperature is low even though the heating fee has been paid. The customers complain the bad heating supply and many contradictions between heating supplier and customers have been resulted. Moreover, the difficulty in collecting heating fees makes the heating supply operation going worse. The above problems not only slow down the commercial progress of "home heating", but also affect the basic benefits of customers seriously.Aiming at the present situation of heating and collecting fees in traditional heating systems, a safe, reliable and intelligent heating system project is proposed to improve the existed single-pipe-stride system in this thesis. The proposed system consists of a central computer management system and a opening device. The central computer management system is responsible for data collecting, processing and storage and the opening device is responsible for unblocking/blocking the valves. The central computer management system delivers control data to the opening device through series ports. The operators control the three-channel valve to complete regulation of the opening flow with the opening device so that the limit setting of heating fee amount and the data delivery can be realized according to the customer requirements. The main idea of the proposed project is based on a new designed three-channel valve. Before heating supply, the valve is blocked automatically, i.e., the channel between pipeline and radiator is blocked automatically. The heat medium flows through pipeline, which is parallel to the radiator. When the operator regulates the open degree of the three-channel intermediation valve by the opening device, the heat medium that strides over the tube decreases automatically as the hot medium increases so that it maintains the total heat medium constant and avoids the water conservancy system out of order.The opening flow of the three-channel control valve can be set by the data saved in memory automatically. After confirming by the operator through the keyboard based on the display of LCD, the opening device controls the opening flow of valve automatically. The experiment results have proved that the proposed system can realize heating control and fee accounting better. We have got award from the Harbin City Development Fund in 2002. |
