A Sliding-Mode Direct Power Control Strategy for DFIG Under Both Balanced and Unbalanced Grid Conditions Using Extended Active Power

Three-level neutral-point-clamped (NPC) converter is widely used in energy conversion systems due to its good properties for high-power systems presenting output waveforms with reduced harmonic distortion. To obtain better system performance, an integral sliding-mode control (ISMC)-based direct power control (DPC) strategy is proposed for NPC converters. The controller achieves three objectives. First, an extended state observer (ESO)-based ISMC strategy, to enforce the active and reactive power to their reference values, is applied in the power tracking loop. ESO is used to reduce the influence of parameter uncertainties. Next, in the voltage regulation loop, a radial basis function neural network (RBFNN)-based adaptive ISMC strategy is applied to regulate the DC-link voltage. RBFNN is used to estimate the load variation, which is considered as a disturbance, to improve the system disturbance rejection ability. An adaptive law is used in the controller to reduce the chattering of reference active power which can reduce the current harmonic distortion. Finally, a proportional-integral (PI) control strategy is applied in the voltage balancing loop to achieve voltage balance between two DC-link capacitors. Experimental results show the effectiveness and superiority of the proposed control strategy for the NPC power converter compared with PI-based DPC strategy.

Download Full-text

Sliding mode direct power control strategy of a power quality based on a sliding mode observer

International Journal of Electrical Power & Energy Systems ◽

10.1016/j.ijepes.2013.10.032 ◽

2014 ◽

Vol 56 ◽

pp. 325-331 ◽

Cited By ~ 13

Author(s):

Ali Djerioui ◽

Kamel Aliouane ◽

Farid Bouchafaa

Keyword(s):

Power Control ◽

Power Quality ◽

Control Strategy ◽

Sliding Mode ◽

Sliding Mode Observer ◽

Direct Power ◽

Direct Power Control

Download Full-text

Integral Plus Resonant Sliding Mode Direct Power Control for VSC-HVDC Systems under Unbalanced Grid Voltage Conditions

Energies ◽

10.3390/en10101528 ◽

2017 ◽

Vol 10 (10) ◽

pp. 1528 ◽

Cited By ~ 4

Author(s):

Weipeng Yang ◽

Aimin Zhang ◽

Jungang Li ◽

Guoqi Li ◽

Hang Zhang ◽

...

Keyword(s):

Power Control ◽

Sliding Mode ◽

Direct Power ◽

Direct Power Control ◽

Grid Voltage ◽

Unbalanced Grid

Download Full-text

Optimal improvement of direct power control strategy based on sliding mode controllers

Computers & Electrical Engineering ◽

10.1016/j.compeleceng.2018.08.013 ◽

2018 ◽

Vol 71 ◽

pp. 637-656 ◽

Cited By ~ 6

Author(s):

Hicham Lhachimi ◽

Yassine Sayouti ◽

Youssef El Kouari

Keyword(s):

Power Control ◽

Control Strategy ◽

Sliding Mode ◽

Direct Power ◽

Direct Power Control ◽

Sliding Mode Controllers

Download Full-text

Adaptive-Gain Second-Order Sliding Mode Direct Power Control for Wind-Turbine-Driven DFIG under Balanced and Unbalanced Grid Voltage

Energies ◽

10.3390/en12203886 ◽

2019 ◽

Vol 12 (20) ◽

pp. 3886 ◽

Cited By ~ 2

Author(s):

Han ◽

Keyword(s):

Power Control ◽

Wind Turbine ◽

Upper Bound ◽

Sliding Mode ◽

Second Order ◽

Direct Power ◽

Direct Power Control ◽

Grid Voltage ◽

Unbalanced Grid ◽

Second Order Sliding Mode

In a wind turbine system, a doubly-fed induction generator (DFIG), with nonlinear and high-dimensional dynamics, is generally subjected to unbalanced grid voltage and unknown uncertainty. This paper proposes a novel adaptive-gain second-order sliding mode direct power control (AGSOSM-DPC) strategy for a wind-turbine-driven DFIG, valid for both balanced and unbalanced grid voltage. The AGSOSM-DPC control scheme is presented in detail to restrain rotor voltage chattering and deal with the scenario of unknown uncertainty upper bound. Stator current harmonics and electromagnetic torque ripples can be simultaneously restrained without phase-locked loop (PLL) and phase sequence decomposition using new active power expression. Adaptive control gains are deduced based on the Lyapunov stability method. Comparative simulations under three DPC schemes are executed on a 2-MW DFIG under both balanced and unbalanced grid voltage. The proposed strategy achieved active and reactive power regulation under a two-phase stationary reference frame for both balanced and unbalanced grid voltage. An uncertainty upper bound is not needed in advance, and the sliding mode control chattering is greatly restrained. The simulation results verify the effectiveness, robustness, and superiority of the AGSOSM-DPC strategy.

Download Full-text