变频器多目标故障诊断及容错控制

发布时间：2018-07-31 14:01

【摘要】：变频器以其优越的性能，被广泛应用在工业领域。然而，作为电力电子产品，变频器会出现各种故障。变频器一旦发生故障，就会给生产和人身安全带来巨大的隐患。提高系统的可靠性势在必行，提高变频器的可靠性体现在两个方面：一方面需要快速的诊断出故障，并定位故障信息，方便维修；另一方面在故障后尽可能让变频器继续运行。变频器的故障类型很多，其中速度传感器故障，电流传感器故障和开关管故障比较常见，本文对这三种故障类型进行研究。首先，针对多开关管的故障诊断，提出了两种诊断方法：改进的三相平均电流法和改进的基于傅立叶变换的归一化三相平均电流法。改进三相平均电流法在传统的三相平均电流法基础上进行改进，提出了新的算法，并且通过数学推导验证了方法的有效性。改进的基于傅立叶变换的归一化三相平均电流法是在传统方法进行改进，应用新的算法和诊断策略，使其在不同负载下对多个开关管开路故障均能有效定位。本文对改进的基于傅立叶变换的归一化三相平均电流法中阈值的选取和诊断方法进行了数学推导，最后在Matlab/Simulink仿真平台上对这两种方法进行了验证。其次，深入研究了单电流传感器矢量控制方法，对前人方法进行改进，将两个轴向的电流误差量引入到龙贝格观测器中，并且对系统的稳定性进行了数学推导，得到观测器的误差矩阵。改进后的方法不仅可以运行在低速状态，而且在中高速下可以正常运行。通过Matlab/Simulink仿真平台验证了该方法的有效性。最后，设计了一种基于滑模控制的速度观测器。该观测器在模型参考自适应观测器的基础上，通过李亚普诺夫稳定性推导，得到速度的表达式。然后通过Matlab仿真平台搭建感应电机模型，通过仿真验证了本文所提方法的有效性。该方法抗干扰性好，观测准确性较高，且不需要复杂的增益系统调节。针对上面的研究内容，，搭建了基于dSPACE的实验平台，该平台具有模拟开关管开路故障的功能。通过实验，对多开关管的开路故障诊断方法和单电流传感器矢量控制方法进行了验证。
[Abstract]:Frequency converter is widely used in industrial field because of its superior performance. However, as a power electronics product, the frequency converter will appear a variety of faults. Once frequency converter breaks down, it will bring huge hidden trouble to production and personal safety. It is imperative to improve the reliability of the system. There are two aspects to improve the reliability of the inverter: on the one hand, we need to quickly diagnose the fault, and locate the fault information to facilitate maintenance; on the other hand, let the frequency converter continue to run as much as possible after the failure. There are many fault types of frequency converter, among which speed sensor fault, current sensor fault and switch tube fault are common. Firstly, two methods are proposed for fault diagnosis of multi-switch transistors: the improved three-phase average current method and the improved Fourier transform based normalized three-phase average current method. The improved three-phase average current method is improved on the basis of the traditional three-phase average current method, and a new algorithm is proposed, and the validity of the method is verified by mathematical derivation. The improved normalized three-phase average current method based on Fourier transform is improved by the traditional method. The new algorithm and diagnosis strategy are used to locate the open circuit faults of multiple switches under different loads. In this paper, the mathematical derivation of the threshold selection and diagnosis method in the improved Fourier transform based normalized three-phase average current method is carried out. Finally, the two methods are verified on the Matlab/Simulink simulation platform. Secondly, the single current sensor vector control method is deeply studied, and the former methods are improved, two axial current errors are introduced into the Romberg observer, and the stability of the system is derived mathematically. The error matrix of the observer is obtained. The improved method can not only run at low speed, but also can run normally at medium and high speed. The effectiveness of the method is verified by Matlab/Simulink simulation platform. Finally, a speed observer based on sliding mode control is designed. Based on the model reference adaptive observer, the expression of velocity is derived by Lyapunov stability. Then the induction motor model is built on the Matlab simulation platform, and the effectiveness of the proposed method is verified by simulation. The method has the advantages of good anti-interference, high accuracy and no complicated gain system adjustment. In view of the above research content, the experimental platform based on dSPACE is built, which has the function of simulating the open circuit fault of switch tube. The open circuit fault diagnosis method and single current sensor vector control method are verified by experiments.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM921.51

【共引文献】