区域热网管网阻力系数的在线辨识与故障诊断

Identification of flow resistance coefficient and fault diagnosis in district heating networks

针对区域热网的特点 ,提出了一种用于区域热网管网阻力特性系数辨识和管网堵漏以及传感器故障诊断的新方法— RC2 方法。该方法将整个管网各管段的阻力特性系数按管段的连接关系分为若干 2到 5维的子空间 ,在每一子空间进行域的收缩 ,从而使各子域不断缩小并逼近各管段的阻力特性系数 ,根据实时测量参数与域的关系可以同时进行管网的故障诊断。本文介绍了该方法的基本原理、数学模型以及域收缩的具体步骤和故障诊断的基本方法 ,最后结合仿真结果对影响参数辨识和故障诊断灵敏度的因素进行了分析。该方法充分考虑了工程实际情况 ,经在沈海热网和辽河热网等工程中的应用表明 ,参数辨识具有很高的可靠性和较高的精度 ,完全可以满足工程需要 ,故障诊断可以和参数辨识同时进行 ,其灵敏度较高 ,误判率很低。

RC 2 (resistance coefficient region contraction) method has been developed for hydraulic process fault diagnosis and parameters identification in district heating networks. The method differs from conventional methods in that identification of the flow resistance coefficient occurs in conjunction with the fault diagnosis sequentially. The paper describes the basic principles and the method to establish and modify range of values for the flow resistance coefficient, Ω . A special geometrical calculation procedure was developed for this procedure. Further analysis was provided for detecting and diagnosing faults. Then, the key to increase the sensitivity and reliability of the procedure was discussed with a numerical example. The method has been applied in two urban heating networks in China.