关键词: 马田系统（MTS）, 支持向量机（SVM）, 马氏距离, 阈值, 故障诊断

Abstract: For solving the existing problems of the establishing threshold methods in MTS，applying the theory of hyper sphere support vector machine，the one-class and two-class hyper ellipsoidal support vector machine models are put forward.The two models can be proved theoretically to transform into quadratic programming problems.The function of threshold of MTS based on the hyper ellipsoidal support vector machine is established.At last，a fault diagnosis example is illustrated applying the new method，and high accuracy rating is reached.

Key words: Mahalanobis-Taguchi System（MTS）, Support Vector Machine（SVM）, Mahalanobis distance, threshold, fault diagnosis