access icon free Power control strategy for photovoltaic system based on the Newton quadratic interpolation

© The Institution of Engineering and Technology
Received 05/03/2013, Accepted 04/11/2013, Revised 16/08/2013, Published 04/02/2014

To maximise the economic benefit, photovoltaic (PV) systems in general operate in the so-called maximum power point tracking (MPPT) mode. However, in certain occasions (e.g. in a microgrid or in a weak system), it is beneficial for a PV system not to always operate in the MPPT mode, but occasionally in the power dispatch mode, because of the top priority of maintaining system stability. To this end, a Newton quadratic interpolation-based power control strategy for PV system is proposed to iteratively obtain the required terminal voltage of PV system by approximating the power–voltage characteristic curve with a quadratic curve. With this control strategy, PV systems can operate in the power dispatch mode to flexibly adjust the active power output in a wide range, or adaptively switch to the MPPT mode if necessary. Details on the convergence rate and the way to achieve the fault ride-through capability are also discussed. Simulation is performed based on a detailed PV dynamical model, illustrating that the proposed method has fast convergence rate and robust performance compared with a revised perturb and observe method which can attain the same function.

Inspec keywords: power control; interpolation; distributed power generation; maximum power point trackers; photovoltaic power systems; power generation control; Newton method; perturbation techniques; fault diagnosis; power generation dispatch; stability; convergence of numerical methods

Other keywords: PV dynamical model; stability; quadratic curve; power dispatch mode; MPPT mode; fault ride-through capability; power-voltage characteristic curve; observe method; Newton quadratic interpolation; photovoltaic system; convergence rate; power control strategy; terminal voltage; maximum power point tracking mode; microgrid; revised perturb method

Subjects: Distributed power generation; Interpolation and function approximation (numerical analysis); Stability in control theory; Power and energy control; Control of electric power systems; Interpolation and function approximation (numerical analysis); Power system management, operation and economics; Solar power stations and photovoltaic power systems; DC-DC power convertors

References

    1. 1)
    2. 2)
      • 2. Sheikh, N., Kocaoglu, D.: ‘A comprehensive assessment of solar photovoltaic technologies: literature review’. Proc. PICMET '11: Technol. Manage. Energy Smart World, August 2011, pp. 1–11.
    3. 3)
      • 21. Keyhani, A., Marwali, M., Dai, M.: ‘Integration of green and renewable energy in electric power systems’ (John Wiley & Sons, 2009).
    4. 4)
    5. 5)
    6. 6)
      • 19. Keyhani, A.: ‘Design of smart power grid renewable energy systems’ (John Wiley & Sons, 2011).
    7. 7)
    8. 8)
      • 25. Sun, W., Yuan, Y.: ‘Optimization theory and methods: nonlinear programming’ (Springer, 2006).
    9. 9)
    10. 10)
    11. 11)
    12. 12)
    13. 13)
      • 16. Li, P., François, B., Degobert, P., Robyns, B.: ‘Power control strategy of a photovoltaic power plant for microgrid applications’. Proc. ISES World Congr., April 2009, pp. 1611–1616.
    14. 14)
    15. 15)
      • 13. Menniti, D., Burgio, A., Sorrentino, N., Pinnarelli, A., Brusco, G.: ‘An incremental conductance method with variable step size for Mppt: design and implementation’. Proc. Tenth Int. Conf. Electr. Power Qual. Utilis., September 2009, pp. 1–5.
    16. 16)
    17. 17)
      • 4. Tan, Y., Kirschen, D.: ‘Impact on the power system of a large penetration of photovoltaic generation’. IEEE Power Eng. Soc. Gen. Meeting, June 2007, pp. 1–8.
    18. 18)
      • 1. Ahmed, S., Mohsin, M.: ‘Analytical determination of the control parameters for a large photovoltaic generator embedded in a grid system’, IEEE Trans. Sustain. Energy, 2011, 2, (2), pp. 122–130.
    19. 19)
    20. 20)
    21. 21)
    22. 22)
    23. 23)
    24. 24)
      • 24. Hildebrand, F.: ‘Introduction to numerical analysis’ (Dover Pubns, 1987, 2nd edn.).
    25. 25)
    26. 26)
      • 3. Hua, C., Lin, J., Shen, C.: ‘Implementation of a Dsp-controlled photovoltaic system with peak power tracking’, IEEE Trans. Power Electron., 1998, 45, (1), pp. 99–107.
    27. 27)
    28. 28)
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