Decoupled d–q Axes Current-Sharing Control of Multi-Three-Phase Induction Machines

A Novel Matrix Transformation for Decoupled Control of Modular Multiphase PMSM Drives

“…The harmonic currents do not contribute to energy production. Indeed, based on the literature, their active control is implemented if power-sharing [17], [18], or fault-tolerantstrategies among the k-set phases are in use [25]- [28], [30]. Finally, if the zero-sequence components 0-o exist (o =1÷g), the related electromagnetic equation is computed as:…”

“…Indeed, only the winding sets' balanced operation can minimize the overall Joule losses [17]. However, with the development of the "series/parallel configurations" [17], [44], [45], the control solutions able to perform the power-sharing among the winding sets have gained more attention, leading to several technical contributions [17], [18], [32], [36], [37]. Also, for testing high-power machines, the power-sharing strategies are a viable solution for performing back-to-back regenerative tests [37], [46], [47], thus avoiding the need for expensive highpower prime movers.…”

“…energy conversion is performed in a single subspace, having the meaning of the machine's time-fundamental model, characterized by electromagnetic equations similar to those of the three-phase motors. The other subspaces have the meaning of the machine's harmonic patterns, highlighting possible unbalance among the stator phases in terms of currents, fluxes, and torque [17], [18].…”

Modular Vector Control of Multi-Three-Phase Permanent Magnet Synchronous Motors

“…Therefore, the state-space model of such a subspace can be found easily in the literature, being identical to that of a three-phase machine [23]. However, the unbalances among the sets in terms of both flux and torque productions are expressed through the harmonic subspaces [9], [19], [24], making the VSD modeling less straightforward for the implementation of modular control schemes.…”

“…By inserting (28) into (24), the time-derivative of the z-set current vector can be expressed as a function of the timederivative of the k-set current vector only:…”