Study of coupled-nonlinearity and its control technique in modern power drive systems

Modern power drive systems are the product of combined power electronic installation with electric motor and its driven part. In a power drive system, there exist various nonlinear links. In this paper, the nonlinear characteristics are first analyzed. Then the coupled relation is studied. It is shown from the research results that the modern power drive system is a coupled high nonlinear system containing various nonlinear links. Some phenomena of oscillation or vibration exist in practical applications of power converter drives and cycloconverter drives, and are introduced. The mechanism of oscillation or vibration is analyzed. A novel technique of controlling or suppressing this oscillation or vibration is also suggested in this paper. The applied effect of this technique in practical vibration suppression engineering are discussed and the applied results are given