Research On Pump's Efficient Operation And Parameters Identification Based On The Anylysis Of Characteristic

As power equipment in heating and air conditioning engineering,pumps have different operating characteristics under different control strategies and operation modes,and it affects the energy consumption of the system to a great extent.We can enrich the operation theory of pumps and provide theoretical guidance for their efficient operation,through the analysis and study of whose basic characteristics and operation rules.So,the following research work has been done based on the analysis of pump characteristics:The basic characteristics of pumps are analyzed and combed in this paper,and the author makes full use of this it to identify pump parameters: Based on the similarity theory of pumps,a method of identifying the efficiency of pumps by using equivalent parameters C or flow rate and head is proposed.The efficiency of any working point in the working area of pumps is identified by analyzing the samples of pumps,which provides a basis for the analysis of pump theory;the pump flow can be identified by using more easily accessible and more accurate electrical parameters,through the experimental study of single and parallel pump system,during which the data of flow,frequency and power were measured in nearly 400 groups..The main control strategies in heating and air conditioning engineering are abstractly classified into four categories: constant pipe network characteristics,constant pressure,variable pressure and throttling.On the premise of efficient operation of pumps and based on the operation mode,the idea of dividing adjustable flow intervals is put forward.At the same time,the Calculation Method of Pump System Efficiency and energy consumption,as well as the dividing calculation models under different control strategies are given;Taking TP65-180/2 pump as a sample,the mathematical model of parallel pump system is established,and its operation characteristics such as adjustable flow interval,operation mode,application of frequency conversion speed regulation technology,efficiency and energy consumption change law under different control strategies are analyzed respectively,which further enriches the theoretical study of pump operation.From the point of view of adjustable flow interval and system energy consumption,it is proposed that the variable pressure differential control is a control strategy which can give full play to the advantages of pump characteristics.The research show that part of the variable speed operation mode is not conducive to energy saving of the system,and that the operating frequency of pump system can not generally be reduced to the minimum allowable operating frequency under the premise of efficient operation of pumps,that is,the advantages of frequency conversion technology can not be fully exploited.This paper analyses and studies the non-adjustable flow interval in constant pressure control.The result shows that this interval is caused by the unreasonablesetting of pressure difference and enlarges with the increase of unreasonable setting value.It also shows that the range of allowable pressure setting value of pump system is limited and generally small.In this part,the calculation program designed by Python language can be used arbitrarily under the control of constant pressure,accurate calculation of allowable pressure difference setting range of pump system provides reference for engineering application;Aiming at the specific flow interval where the energy consumption of single-pump frequency conversion operation is greater than that of double-pump frequency conversion operation in variable pressure control,the characteristic operating points are analyzed and studied through multi-dimension calculation.The results show that the specific interval always exists in variable pressure control under the premise of reasonable selection,which has great potential for energy saving for large parallel pumping systems operating in this particular area for a long time;Finally,the above conclusions are used to guide pump selection under specific circumstances from the point of view of operation.