Complete Quadratic Linearisation of Machine Models

In this paper, a quadratic linearisation technique based on Poincare´s work is proposed. Unlike the existing feedback linearisation techniques, the proposed method does not introduce singularities in the system. Moreover, we make the quadratic linearisation for a class of systems complete in the sense that higher order terms are not left behind in the system as is common with existing quadratic linearisation techniques. The proposed linearisation technique is applied for induction motor and PM motor models.