subject: Energy efficient building HVAC system optimization - energy-saving buildings, heating - HVAC & R industry [print this page] Energy efficient building HVAC system optimization - energy-saving buildings, heating - HVAC & R industry
HC HVAC & R Network Abstract: Objective: To study the intelligent building HVAC systems to achieve effective way of energy saving and optimization methods. Methods: Comparison of major energy-consuming units within the building energy-saving measures. The results achieved on the BA control system (mainly HVAC system) Sensor , Actuator, controller, network, optimize certain aspects of the classification, from the system structure and parameters of the various possible to find the best match to the best overall performance, thereby enhancing the efficiency of the system. Conclusion: The establishment of intelligent building HVAC system energy management and control system optimization of the basic starting point, optimization principles and technical measures for the realization of intelligent building energy efficiency has important practical significance, BAS system is the intelligent way to building energy efficient.
Energy efficient building HVAC system optimization
An overview of Intelligent Building Energy is a worldwide trend and the trend is also pressing China's reform and development requirements of the 21st century architectural career development a priority and focus. Energy conservation and Environmental protection Is the key to achieving sustainable development. Theory of sustainable development, building energy efficiency is the key to further improve energy efficiency, building energy efficiency standards irrespective of whether the formulation of specific projects or engaged in the design, should be to improve the energy efficiency of building energy efficiency as the focus. Intelligent building is no exception, the owners of the Intelligent Building direct motive is highly modern, comfortable and at the same time to achieve a high degree of Energy A significant reduction in consumption in order to achieve savings of building operating costs.
2, Intelligent Building HVAC Energy Management and Control System Optimization
Intelligent Building Building Automation System will be building a system integrating all the equipment, information sharing, integrated management, its role and benefits are enormous, and efficiency to achieve these effects, we must implement optimization, building intelligent Chemical industry Design and optimization process compared to conventional design, has the following characteristics: 1) possible from the system structure and parameters to find the best match, Shi best overall performance, thereby enhancing the system Xiaoshuai, reduce investment and operation costs ; 2) is on the system and its quantitative process model simulation, reducing control areas, improve reliability and stability, to minimize the probability of failure may limit the system response output optimization; to save energy by optimizing the control scheme aims is a kind of "active energy", which is different from the wall structure, windows and doors and setting the transformation in the form of "passive energy conservation."
III BA intelligent building system optimization methods (mainly for the HVAC system)
1 Optimization of control strategy Air processor P DDC usually work D control, select the appropriate parameters P D work and stable operation of the air conditioning system is critical. High coefficient of P workers D, air-conditioning on indoor temperature fluctuation response curve steep, reaches the set temperature of the transition process shorter; opposite low coefficient of P workers D, reaches the set temperature of the transition process longer. But not P D coefficient the higher the better work, otherwise easily lead to instability of DDC control system, the performance of the indoor temperature oscillation and the water side Electric control valve Periodic back and forth movement can not be run at a fixed opening. P D can solve most of the work situation of the air conditioning control, thermal inertia for the theaters and other large air-conditioned places, by a high coefficient of P D work to improve the air conditioning unit on the load change response time is not enough to solve the problem. Then you can use two-level control, respectively in air conditioning and indoor air Road, installation of temperature sensors, the room temperature set to complete by the main DDC controller, valve driven by the Deputy DDC temperature sensor under the air duct and the main DDC's instruction to complete, due to changes in speed wind tunnel temperature changes in room temperature, this control method to accelerate the system response to temperature fluctuations. In the actual engineering design, BA saving control system for air conditioning can use a variety of means, such as indoor and outdoor baking value comparison, the concentration of carbon dioxide and other pollutants in outdoor air test method to determine, based on the regular schedule operations so. Engineering design flexibility as may be necessary to achieve optimal results. For example, office, shopping malls and so on, summer and autumn in the early morning when the air handler through the program starts a new domain Fans ), Using cool outdoor air for indoor ventilation precooling overall, saves the new wind energy and also enhance the indoor air quality.
2, the optimization of control BA
usually follow the central principle of centralized control station. Sometimes has its inconvenient side. In some cases (such as conference rooms) will be air conditioning, ventilation system parameter setting function placed in the scene may be more consistent with the needs of users. DDC itself does not provide this functionality, you need specialized components to achieve. VRV type of function close to the device control panel settings to room users tremendous convenience and comfort, where necessary to actively use.
3, direct digital control (DDC) optimization
Mainstream BA system supplier can provide different sizes and capabilities of the DDC, freezing rooms, thermal monitoring station is where many large-scale control should be given priority to reduce the failure rate and the communication between the controller. On the air handler, new fans, fans generally use medium or small, the controller can be. In recent years, programmable logic control device (PLC) has progressed rapidly, their application is no longer limited to industrial situations, the air conditioning and ventilation equipment, control engineering field should not be excluded.
4, control network optimization Scalability and flexibility to meet under the premise of controlling the network topology should be as simple as possible, clear, irrespective of the RS485 bus or bus control network based on LonTalk is true. Branch, multi-grade network management complexity and low reliability. LonTalk bus in theory could form an arbitrary topology networks, routing design of this randomness, if used properly, in engineering practice is still a technical risk, and may increase the system's investments. Minor works as far as possible the use of bus-based Rs485 control network, a "hand in hand" of wiring, large-scale projects can be considered a ratings floor.
5, BAS control center BAS control center responsible for monitoring the air-conditioning, ventilation, power systems, general and fire control, security surveillance sharing a room. Since the room is usually far from the freezing room, boiler room, where the remote operation of these key devices is not appropriate. Recommended practice is to freeze-site control room, engine room and boiler room and the other to set a monitoring sub-stations, by the sub-station is responsible for freezer, boiler monitoring, and the sub-station functions authorized for the cold and heat source equipment limitations.
