Decentralized Control of a Nine-Phase Permanent Magnet Generator for Offshore Wind Turbines

Abstract

This article presents a decentralized current control approach for a nine-phase wind turbine generator. This type of generator has three different three-phase stators sharing the same machine yoke, connected to the grid by means of three different Voltage Source (VS) back-to-back power converters. Due to the machine configuration, magnetic couplings are present between the three stators, complicating the design and implementation of the machine current controllers. Rather than a centralized control approach, this paper proposes a methodology to design a decentralized machine control to regulate the active and reactive power flowing through each stator independently. A complete dynamic analysis is performed in order to design the controller to reduce the coupling effects within the machine while ensuring a proper dynamic performance. The control strategy is validated through simulation and experimental results. Index TermsPermanent magnet machines, multiphase variable-speed drives, decentralized control, wind energy.

Optimal operation of hybrid AC/DC microgrids under uncertainty of renewable energy resources: A comprehensive review

“…In this method every wind turbine acts as an independent unit and possesses its own converter [39]. There are also several parameters that must be controlled and taken into consideration during the implementation of wind turbines such as voltage and frequency control, active power control, protection, communication, etc.…”

Finite Control Set Model Predictive Control of Six-Phase Asymmetrical Machines—An Overview

“…VV1 (36,53) VV2 (52,38) VV3 (54,20) VV4 (22,50) VV5 (18,30) VV6 (26,19) VV7 (27,10) VV8 (11,25) VV9 (9,43) VV10 (41,13) VV11 (45,33) VV12 ( To improve the performance of a six-phase PMSM drive at low speeds, a VV-PCC strategy based on an extended set of twenty-five virtual vectors (EVV-PCC) was proposed in Reference [112]. The extra twelve virtual vectors {v v13 , ..., v v24 } shown in Figure 5 have an amplitude of 0.345 • U dc and are created by the combination of one medium-large and one small vector, with the same phase in the α-β subspace (Figure 2), during a sampling period with duty cycles given by:…”

“…In addition to the reduced current or voltage ratings per phase, lower torque harmonics, improved fault-tolerant capabilities and additional degrees of freedom, multiphase machines also offer other advantages over their three-phase counterparts, namely: improved winding factors, reduced harmonic content in the magnetomotive force (MMF), lower rotor losses and lesser harmonics in the dc-link current [1,[24][25][26]. Nowadays, electric drives based on multiphase machines are employed in a wide range of areas, such as aircraft [27,28], electric or hybrid vehicles [29], locomotive traction [30], high-speed elevators [31], ship propulsion [32], spacecraft [33] and wind energy applications [34][35][36].…”

Dynamic multi‐agent dc‐bus reconfiguration in modular motor drives with a stacked polyphase bridge converter

“…MMDs that are composed of a multiple of three motor and PE modules-the so-called multi-three-phase machines [4,5]-are of particular interest, since they can be considered as a group of three-phase winding sets, fed by standard three-phase two-level voltage source inverters (2L-VSIs). From the control point of view, these multithree-phase machines can make use of the well-consolidated three-phase control strategies, extending the modularity of the hardware to the control as well [6,7]. The combination of a three-phase winding set, its 2L-VSI and its dedicated threephase controller in an MMD can be seen as an agent in a multi-agent system.…”