Real-time implementation of sliding-mode field-oriented control for a DFIG-based wind turbine

Abstract

Summary Wind energy has many advantages because it does not pollute and is an endless source of energy. The most used electric machines for horizontal axis wind turbine is the doubly fed induction generator (DFIG). In this paper, the authors propose a real‐time field‐oriented control based on sliding mode (FOC‐SM) for a DFIG prototype connected to the grid via a 3‐phase transmission line. To track the desired DC voltage reference at the output of the DC link and to maintain constant the electric power factor at the step‐up transformer terminals controlled by grid‐side converter, a vector‐oriented control combined with sliding mode is introduced; and to force independently the rotor currents to track a specified reference defined from the required stator active and reactive powers, controlled by rotor‐side converter, an FOC‐SM control scheme is proposed. The DFIG rotor is coupled to the grid via a back to back power electronic converter, whereas the stator is directly linked to the grid. The proposed control scheme is experimentally validated on a 1/4 HP DFIG prototype and tested under constant and variable wind speed, maximum power extraction, and fault grid conditions. The real‐time results show that the proposed controllers achieve a high performance under ideal and no‐ideal grid conditions. Moreover, the proposed scheme is robust in presence of uncertainties, which usually exist in the real system.

Real-Time Simulator of DTC–FOC-Based DFIG During Voltage Dip and LVRT

“…1. Equation (1) is rewritten by choosing all parameters referring to stator side (Wang et al 2017;Djilali et al 2018).…”

Resilient cyber physical infrastructure for single‐phase dual inverter with sliding mode control

“…The state variables are computed by Equations (10) and (11). The _ x 1 , _ x 2 , and _ x 3 are the derivatives of error variables and given by (37), (38), and (39):…”

“…where V s is the source voltage, C is the output filter capacitor, R is the load, and u is the switching function. The derivatives of sliding function ( _ S) obtained by incorporating (37), (38), and (39) is expressed as (40):…”

“…Generally, the control of inverter is achieved by PI, PID, and direct power control. The sliding mode control (SMC) 22,[31][32][33][34][35][36][37][38] provides the dynamic response to the nonlinear systems with the property of hysteresis. The steady-state error of the system is low compared with other controllers.…”

Lagrange interpolating polynomial–based deloading control scheme for variable speed wind turbines

“…In general, the rotor of the DFIG is fed through a back-to-back pulse width modulation (PWM) converter as shown in Figure 3. 4,[25][26][27] The detailed modeling of DFIG is described in Djilali et al 25 and Shihabudheen et al 26 The proposed control approach of the generator/rotor-side and grid/load-side converters for the active and reactive power control loops is shown in Figures 4 and 5, respectively. During frequency events, the net output power (P * wind ) extracted from WTG is the combination of the dynamic deloading power ( p * ref ) and power contribution (ΔP sp ) by the frequency-emulated inertia and droop control, which is shown in Figure 4.…”