Robust self-tuning MTPA algorithm for IPMSM drives

Abstract

This paper presents robust self-tuning maximum torque per ampere (MTPA) control algorithm for an interior permanent magnet synchronous motor (IPMSM) drives. Proposed algorithm utilizes conventional control scheme, where speed controller produces stator current command signal for the MTPA block. That block decomposes commanded current I <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">s</inf> into its components along direct and quadrature axes i <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</inf> and i <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</inf> respectively, which are used as a current commands for the current control loops. MTPA angle γ, which is used for the decomposition is defined by the MTPA tuning algorithm, which continually varies that angle trying to find the one which provides the minimum of stator current at the given load torque.