楼宇空调水系统温度传感器固定偏差故障的诊断方法

FAULT DETECTION AND DIAGNOSIS METHOD FOR THE TEMPERATURE SENSORS WITH FIXED BIAS IN WATER SYSTEMS OF HVAC

针对HVAC水系统中温度传感器固定偏差的故障,提出了一种基于分析冗余和数理统计的故障诊断方法。该方法从能量守恒出发,通过选择不同控制体并建立相应守恒方程的残差表达式,利用数理统计方法将固定偏差故障的诊断问题转化为求解最小值问题,最终通过建立并求解诊断方程组获得传感器的固定偏差。还讨论了诊断所需数据样本的选取和诊断结果可靠性的判断。诊断方法在已建立的系统仿真器上进行了验证,结果表明该方法能够用于诊断由于漂移而引起的传感器故障。

A fault detection and diagnosis method is presented, which based on analytical redundancy and statistics, for detecting and evaluating the temperature sensors with fixed bias in HVAC water systems. Based on energy conservation, analytical redundancy models of measurements and measurement residuals of each selected control volume are set up, and then the FDD problem could be changed into solving the minimization problem by using of statistic theory. The equations for FDD are set up and solved to obtain the fixed bias of measurements of temperature sensors. It is discussed to select data samples for FDD as well as reliability in this paper. The presented FDD method is tested and validated by simulation of chilling water systems. The results show that this method could be used to detect and evaluate the fault of fixed bias of temperature sensor caused by zero shifts.