LIAPUNOV函數에 의한 同期電動機의 동기인입현상 解析 = Liapunov Stability Analysis About Pull-In Characteristics of Synchronous Motor

다국어 초록 (Multilingual Abstract)

A synchronous motor started as an induction motor must be synchronized as soon as possible by the application of field at any point.
Unfortunately, the dynamic motion equations, describing the synchronized process, that is, describing the pulling-into-step process, are represented by complicate and nonlinear differential equations which have no analytical techniques. However, practical criteria for predetermining with adquate accuracy whether a given motor will or will not pull into step under specified conditions, must be necessarily given. Futhermore, it is impossible to obtain the accurate solution of the closed form by conventional techniques. Even though they are obtained, they does not show the stable regions over 4 quadrants. Specially, the accurate observations about the continuous variations of slip and load angle are very important for the stablized control of synchronous motor and all systems with them. The abnormal and unstable operations such as hunting pulling out and etc. are fatal to the life of machine itself and all systems with them. Therefore, in this paper, the stable regions in the sense of strictness over 4 quadrants, the analytical and the experimental techniques, for cylindrical synchronous motor are introduced in detail. These techniques used in this paper are based on the construction and analysis of Liapunov function, derived from the Lagrange-Char-pit method which is one of the solution techniques for partial differential equations. The theory of the various stable regions and optimal points for applications of field, which can be predicted the success or the failure of pulling-into-step under the variations of load ratio and damping ratio is presented and also is proved by experimental results.