Vibration diagnostic method of permanent magnets generators - detecting of vibrations caused by unbalance

This paper presents a new vibration diagnostic method designed for diagnose of permanent magnets (PM) generators. Those machines are commonly used in small wind turbines. The described method is very innovative and unique. Specific structural properties of machines excited by permanent magnets are used in this method - electromotive force (EMF) generated due to vibrations. There was analysed number of publications which describe vibration diagnostic methods and tests of electrical machines with permanent magnets and there was no method found to determine the technical condition of such machine basing on their own signals [1,2,3,4]. In this article several issues will be discussed: the method genesis, the similarity of permanent magnet machines to vibration sensor, mathematical model, and results of simulation and laboratory tests. The method of determination the technical condition of PM electrical machine basing on its own signals is the subject of patent application No P.405669 [5], and it is the main thesis of author´s doctoral dissertation.