New control strategy for permanent magnet synchronous generator (PMSG) wind turbine

Abstract

Due to extensive research in the wind turbine community, advanced technologies have been emerged to obtain the proper operation from wind turbines. However, there are some features needed to be improved to have the best energy conversion system. This thesis is focusing on following areas which are challenges for wind turbine operators encounter: 1. Improving Total Harmonic Distortion (THD) by designing an advanced control strategy. 2. Inter-turn fault detection at early stage. In the first section of this thesis, a Sliding Mode Control (SMC) based scheme is proposed for a variable speed, direct-driven Wind Turbine Conversion System (WTCS) equipped with Permanent Magnet Synchronous Generator (PMSG) connected to the grid. In this work, diode rectifier, boost converter, Neutral Point Clamped (NPC) inverter and L filter are used as the interface between the wind turbine and grid. This topology has abundant features such as simplicity for low and medium power wind turbine applications. It is also less costly than back-to-back two-level converters in medium power applications. SMC approach demonstrates great performance in complicated nonlinear systems control such as WTCS. The proposed control strategy modifies Reaching Law (RL) of sliding mode technique to reduce chattering issue and to improve THD property compared to conventional reaching law SMC. The effectiveness of the proposed control strategy is explored by simulation study on a 4 KW wind turbine, and then verified by experimental tests for a 2 KW set-up. Second section of this thesis proposes a model-based Fault Detection and Localization (FDL) strategy of a surface-mounted PMSG wind turbine. One of the prevalent faults in wind turbines is Inter-turn Short Circuit (ISC) fault in the generator of WTCS. To elaborate the fault and observe the consequences, a 120 KW wind turbine equipped with PMSG is being modeled while injecting the fault during normal and steady state operation. Geometric Approach (GeA) offers plentiful features for FDL in nonlinear system control applications. It can operate as a built-in function of the WTCS control system in which ISC fault is being detected and localized when occurred in the winding of the stator of PMSG. The GeA is a model-based technique that works based upon the governing equations of the generator of wind turbine. The effectiveness of the proposed FDL scheme is justified by co-simulation of wind energy conversion system using Maxwell, Simplorer, and Matlab software packages.

Date	30 Nov 2020
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	Maarouf Saad (Supervisor) & Handy Fortin Blanchette (Co-supervisor)