Design Of Chiller Plant Control System

Energy of China lacks seriously and is consumed highly. Particularly air conditioning consumes most of energy. For the sake of the running efficiency of chiller, convenient operation, improving comfortable quality of air conditioning, Chiller Plant Control System is recognized and applied more and more by customer. This article does some introduction in the domestic and international application background and effect to this system.The different air conditioning water system has different control strategy. This article introduces a type of most common air conditioning water system. Reader can understand which facility should be configured in air conditioning water system of building. Reader can also understand the work principium of water pipe system.The thesis introduces definition, function, characteristics, function and the control object of Chiller Plant Control System later. The article analyzes the work principium and method of saving energy to all kinds of controlled objects. Some scientific control strategies for different controlled equipments are submitted.Then this article describes a real Chiller Plant Control project design in detail. Firstly the thesis introduces the hardware design of this project: 1.Air conditioning water system; 2.Control goal, object and total point list; 3. Direct Digital Controller Introduction; 4. Distribute these points to each DDC; 5. Control network protocol; 6. List of control products and introduction of control products.Then this article describes the software design of this project: 1. Structure of Chiller Plant Control System & Control flow chart of outer assistant equipments of chiller; 2. Control program design of all kinds of controlled equipments.Control software designs for chiller in this project have: Chiller lead/lag condition and flow chart; Parameter explanation of chiller lead/lag control; Design of chillers rotation control.Some programs to control chilled water pumps and cooling water pumps include rotation and standby control. These programs can be referenced. This article describes these programs in detail.The function of electric heating for freezing protection in the design of cooling tower control can be chosen at future project design. Rotation programs to control cooling tower can be referenced also.There is a special function in the design of heating exchange machine control: utilizing lower temperature cooling water exchanges cool capacity to chilled water in winter.Utilizing the network communication can monitor the internal parameter of each chiller, saving a great deal of signal cables. At the same time all types of status signals or setpoints can be sent to monitor computer by control network. All data and flow chats can be displayed graphically in the computer. It will be convenient very much to operate or manage Chiller Plant Control System daily. So it is much important to insure the communication of control system network. At last chapter of this article analyzed the communication problem that even happened in this project. According to research and commission, the thesis submits a solution. The process of research can be referenced.Saving energy is one of the goals that design Chiller Plant Control System. At the end of design and commission people should analyze and compare energy consuming. This article analyzes and calculates the saving energy rate that brings to customer after they apply Chiller Plant Control System according to automatic data record by controller.The thesis summarizes the purpose with design of Chiller Plant Control System finally.