【作者】 丁毅；

【导师】 黄向华；

【作者基本信息】 南京航空航天大学 ， 航空宇航推进理论与工程， 2005， 硕士

【摘要】 针对传感器与执行机构失效问题,本文研究了航空发动机数控系统故障诊断技术,内容涉及航空发动机模型的建立、控制系统设计及故障诊断逻辑研究。 首先针对部件特性数据缺乏的情况下如何对燃气轮机建模的问题,提出了基于相似理论的建模方法;针对模型失配问题,以某型涡扇发动机为对象,对基于部件性能修正的自适应模型进行了研究;结合实际的硬件平台,对所建模型的实时性和精度进行了验证。 为了发动机闭环控制下的故障诊断,结合单神经元网络,采用相似理论建立了航空发动机转速自适应 PID 控制器,并在基于 DSP 和 CAN 总线的电子控制器上进行了验证。 开展了基于部件跟踪滤波器的发动机数控系统故障检测、隔离与适应研究,提出了采用多参数寻优技术的部件性能跟踪策略;针对发动机数控系统中的传感器与执行机构故障,进行了实物在回路仿真试验验证。 在基于阈值判断的传感器故障检测、隔离与适应逻辑基础之上,提出一种新的基于模式识别技术的发动机传感器故障诊断方法。该方法以自适应模型为基础,利用传感器测量值与模型计算值的偏差产生部件性能修正因子,进而形成唯一的故障模式对传感器故障进行有效诊断。更多还原

【Abstract】 Sensors and actuators failure diagnosis of aero-engine digital control system is studied, and the problems of engine modeling, control system design and fault diagnostic logic are dealt with in this paper. A new method describing the gas turbine performance model in case of lacking of component characteristic is presented based on similarity theory. Adaptive model based on component characteristic tracking was introduced to resolve the problem of model unfitting. A turbofan engine model is developed to illustrate the real time performance and the precision on the hardware platform. An adaptive speed control method combining the PID and single cell artificial neural network was proposed. The controller is realized with an EEC based on DSP and CAN Bus. The aeroengine sensor and actuator failure detection, isolation and accommodation system based on extended Kalman filter for a digital control system is developed, and a strategy to adapt the component characteristic using multivariable optimization is proposed. Both algorithms are verified by simulaton with fault diagnosing computer in loop. A novel method based on pattern recognition techniques is proposed. If a measurement set is fed to an adaptive performance analysis algorithm, a set of component performance modification factors(fault parameters) is produced, from which sensor faults patterns can be recognized.更多还原