Behaviour of PMSG wind turbines with fractional controllers to a voltage decrease in the grid

Env Prog and Sustain Energy

2020

This study investigates the design of robust nonlinear controller for control of voltage and frequency of variable‐speed standalone Wind Energy Conversion System (WECS). The variation in wind‐speed and load raise the oscillation in terminal‐voltage and frequency. These oscillation need to be minimized for enhancing the power management. To overcome this issue, an Intelligent Proportional Integral Terminal Sliding Mode Controller (iPI‐TSMC) is proposed. Proposed iPI‐TSMC establishes a fast‐finite‐time convergence with minimum steady‐state error. Also this controller is robust against the wind velocity perturbation, load variations, and external disturbances. Closed‐loop stability of the proposed controller is validated using Lyapunov‐stability‐theorem. The cogency of the proposed iPI‐TSMC has been validated through MATLAB/simulink environment for different operating conditions. Also performance of iPI‐TSMC is compared with fractional‐order‐proportional‐integral (FOPI) and conventional integer‐order‐proportional‐integral (IOPI) controllers. The simulation results, signifies the efficacy of iPI‐TSMC as compared to other controllers. Feasibility of proposed iPI‐TSMC controller is verified in real‐time HIL simulator using op4510 platform. Statement of Industrial Relevance Simulation analysis and the comparative study of iPI‐TSMC with FOPI, and IOPI shows better performance to keep constant terminal‐voltage during different wind‐profiles, load variation, and external disturbance. Also, performance assessment of iPI‐TSMC for different matrices during varying wind‐profiles is found superior than FOPI and IOPI controllers. Performance validation of proposed iPI‐TSMC for varying wind‐velocity and load in real‐time HIL simulator op4510 platform shows the feasibility of the proposed controller, which makes it suitable for real‐time application.

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Section: Introductionmentioning

confidence: 99%

Intelligent Proportional Integral Terminal Sliding Mode Control for variable speed standalone wind energy conversion system

Env Prog and Sustain Energy

2020

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“…A frequency-domain scheme for the fractional-order controller design is presented in Reference 23 to provide stability, robustness, and optimal dynamic performance of the system. Fractionalorder controller provides comparatively better results for total harmonic distortion (THD) than integer-order controller 24 . FOPI are utilized for grid connected PMSG via back-to-back converters for extracting maximum power with improved power factor 25 The article includes the mathematical modelling of PMSG and wind turbine, system description and control scheme, simulation-analysis, results, and discussions.…”

Section: Introductionmentioning

confidence: 99%

Comparative analysis of fractional order PI and integer order PI based controller for hybrid standalone wind energy conversion system

Env Prog and Sustain Energy

2019

This article presents a comprehensive analysis of fractional order proportional integral (FOPI) and integer order proportional integral (IOPI) controllers for voltage and frequency control of a variable speed hybrid standalone wind energy conversion system. Variations in wind velocity and load introduce the changes in terminal voltage and frequency. This can be controlled by an appropriate controller with satisfactory response. In this work, FOPI controller is proposed for controlling the terminal voltage and frequency. Dual second order generalized integral phase locked loop (DSOGI‐PLL) is utilized to track the system frequency. Fractional‐order controller is implemented for voltage source converter, which makes it robust due to their fractional characteristics. FOPI (PIλ) provides an additional degree of freedom (λ), along with proportional gain (Kp) and integral gain (Ki). The robustness of the controller is validated through simulations in MATLAB/simulink and its performance is compared with IOPI under various operating conditions. The results show that, FOPI based controller is able to maintain the terminal voltage and frequency constant with improved transient response in comparison to IOPI. Finally, performance assessment of the controllers is carried out using performance metrics.

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Performance Analysis of Fractional-Order PI-Based Controller for Variable Speed Hybrid Standalone WECS

Renewable Energy and Climate Change

2019