On-line estimation of the stator resistance of a six-phase induction machine

Abstract

This paper proposes a technique to determine on-line the stator resistance of a six-phase induction machine in a six-phase drive system. Besides the stator resistance, the stator leakage inductance can be also estimated. These parameters are obtained by solving a least squares minimization problem. The technique is conceived to be used on-line with the drive strategy without disturbing machine electromagnetic torque. Experimental results are used to demonstrate the feasibility of the proposed technique. 746 0-7803-7420-7/02/$17.00 © 2002 IEEE

Parameter Estimation of Asymmetrical Six-Phase Induction Machines Using Modified Standard Tests

“…However, such approaches are based on the fundamental assumption that the stator leakage inductances (L ls ) in the x-y and zerosequence subspaces are equivalent to the one in the α-β subspace. Though this assumption has been verified in some cases [6], [7], [13], it is not always true. As a matter of fact, it has been pointed out that the leakage inductances in the fundamental (α-β) and non-fundamental subspace can be very different one from the other [8], [14], [15], depending on the machine stator winding design.…”

“…Unlike three-phase machines where L ls /L lr has been defined in IEEE Std-112 based on experience and empirical observations, the lack of knowledge on L ls /L lr hinders the direct use of standard tests in multiphase machines. Consequently, some researchers have proposed to use parameter information from the x-y [6], [7] or zero-sequence subspaces [13] together with standard tests in α-β subspace for complete parameter estimation. However, such approaches are based on the fundamental assumption that the stator leakage inductances (L ls ) in the x-y and zerosequence subspaces are equivalent to the one in the α-β subspace.…”