Experimental Study On Some Problems Of Energy-saving Control Of Air Conditioning Water System

With the high-speed development of social economy in our country, the proportion of building energy consumption in total energy consumption is becoming more and more big and it has increased from24.5%in2007to32%in2012. The Large public building energy consumption accounts for22%of total energy consumption and the tower consumption of the central air conditioning system for large-scale public buildings of the total consumption of50-60%.So, the central air conditioning system will become the focus of building energy efficiency. In the actual operation of the air conditioning system, firstly, most of the water system of air-conditioning terminal without continuous electric control valve, it is difficult to realize the regulation and control of the terminal equipment in air conditioning water system, which increases the energy consumption of water system. Secondly, air conditioning water system vary considerably in the start time and start way, which depending on the operating personnel subjective experience start-stop system, lack of scientific decision-making. In addition, in many air conditioning water systems with frequency conversion control, the basis of water pump frequency conversion control---differential pressure water system monitoring location choice is varied, leading to circulating pump energy consumption of different sizes. Therefore, in view of the above problems, according to the results of the detection and diagnosis of actual air conditioning system and the requirement of the air conditioning water system problems, constructing the test system of intelligent central air-conditioning control. Research and development in view of the above question, it has an important academic and practical value on energy saving and reducing the energy consumption of air conditioning system.Firstly, based on an actual air conditioning system, regulating common problems to control the air conditioning water system, design and construction the test system of intelligent central air-conditioning control, which including the air conditioning water system, electric system and network control system, testing and analysis of the characteristics of electromechanical equipment systems on the basis of the test equipment, the pipeline, sensor, actuator etc. lay the experimental foundation for experimental research work on the follow-up. Secondly, this paper introduction air conditioning water system is the most unfavorable hydraulic loop and the concept of the most unfavorable thermodynamic loop. For no valve position feedback at the end of the air conditioning water system, present the most unfavorable thermodynamic loop identification method that based on room temperature and return water temperature difference. Through experiment verify the feasibility of this method.Thirdly, for the air conditioning system start time and start mode, experimental study on the parallel pump start sets and pre-cooling before work start time. The results show that. In the united start mode is more energy efficient than the separate start mode. Lastly, studying on the pump frequency control pressure reference point selection, the results show that, when the differential reference point at the middle position of the main pipe, the pump energy consumption is the lowest.The above problems are the common problems of the air conditioning water system, studying on the control method of air conditioning water system have great reference value.