Comparative Study of the Effects of Machine Parameters on DFIG and PMSG Variable Speed Wind Turbines During Grid Fault

Abstract

This study investigates the transient performance of two variable speed wind turbines (VSWTs), namely doubly fed induction generator (DFIG) and the permanent magnet synchronous generator (PMSG), that are widely employed in wind energy conversion, considering their machine parameters. The machine parameters of both wind turbines were changed considering different scenarios, while keeping other parameters constant, to study the behavior of the wind generators. This study was carried out using the same operating conditions of rated wind speed, based on the characteristics of both wind turbine technologies. The wind turbines were subjected to a severe three phase to ground bolted fault to test the robustness of their controllers during grid fault conditions. Efforts were made to carry out an extensive comparative study to investigate the machine parameters that have more influence on the stability of the different wind turbines considered in this study. Simulations were carried out using power system computer-aided design and electromagnetic transient including DC (PSCAD/EMTDC). Effective machine parameter selection could help solve fault ride-through (FRT) problems cost-effectively for both VSWTs, without considering the external circuitry of and changing the original architecture of the wind turbines.

Robust control of wind turbine based on doubly-fed induction generator optimized by genetic algorithm

“…where Cp is the power coefficient, which is defined by the ratio between the total extracted power and the incident one [17]. This coefficient depends on λ, the velocity ratio, and β the pich angle, it is formulated by the following function [16], [20]:…”

“…The ADRC is a robust control strategy which is based on the model system extension using a state observer extended state observer (E.S.O) to have an estimation and to cancels, in real time, all disturbances affecting the system whether internal or external [15], [16], [18], [24]- [26]. To explain the principle of the ADRC, we treat the case of a first order system:…”

“…The ADRC allows an estimation, using a state observer, of modeling uncertainties and external disturbances, and a compensation for them in real time [20]. The objective is to have a faster observer dynamic than the closed loop system one, as well as a reduced noise sensitivity [15], [16], [18], [28]. The genetic algorithm is used to determine the Kp, β1 and β2 parameters.…”

“…In recent years, several works have dealt with the DFIG command used in wind energy conversion system (WECS) by active disturbance rejection control (ADRC) [14]- [16]. With this control method, the system is able to compensate external disturbances and those due to parameter changes.…”

Improved control for DFIG based wind power system under voltage dips using ADRC optimized by genetic algorithms

“…In the litera-ture, this technique is recognized to be very effective and efficient in finding optimal solutions to optimization problems. It makes it possible to avoid local minima constituting a major problem in the case of nonlinear systems [33,34].…”