EXPERIMENTAL ANALYSIS OF HYBRID ENERGY STORAGE SYSTEM BASED ON NONLINEAR CONTROL STRATEGY
Keywords:Integral sliding mode control, Hybrid energy storage system, Photovoltaic system, Super-capacitor, Battery, PI control, Dc-microgrid
In this paper, a nonlinear integral sliding mode control for a hybrid energy storage system (HESS) based stand-alone dc microgrid has been proposed and applied experimentally. This hybrid system comprises a PV, super-capacitor, and battery. A classical PI-based linear control strategy has been designed to control battery and super-capacitor systems based on decoupling the high and low-frequency components to estimate reference current. Since the frequent discharge during operation, super-capacitor power can reach the lowest value, affecting controller performance and making the system unstable. From the experimental result, a nonlinear Integral sliding mode control ISMC is performed as an inner loop controller to regulate battery and super-capacitor power. Also, the PI controller is implemented as an outer loop controller to regulate the dc-link. The proposed control approach is compared with the linear PI controller to improve life extension and minimize stress on the battery. As a result, the proposed control strategy has achieved high dynamic system performance.
(1) A. Attou, A., A. Massoum, M. Chadli, Comparison study of two tracking methods for photovoltaic systems, Rev. Roum. Sci. Techn.– Électrotechn. et Énerg, 60, 2, pp. 205–214 (2015).
(2) P.S. Sikder, P. Nital, Incremental conductance based maximum power point tracking controller using different buck-boost converter for solar photovoltaic system, Rev. Roum. Sci. Techn.–Électrotechn. et Énerg, 62, 3, pp. 269–275 (2017).
(3) B.K. Oubbati, M. Boutoubat, A. Rabhi, M. Belkheiri, “Experiential integral backstepping sliding mode controller to achieve the maximum power point of a PV system,” Control Engineering Practice, 102, p. 104570, Sep. 2020,
(4) B. Yang et al., “Perturbation observer based fractional-order sliding-mode controller for MPPT of grid-connected PV inverters: Design and real-time implementation,” Control Engineering Practice, 79, pp. 105–125, Oct. 2018,
(5) M. Jaszczur, Q. Hassan, “An optimisation and sizing of photovoltaic system with super-capacitor for improving self-consumption,” Applied Energy, 279, p. 115776, Dec. 2020,
(6) S. Kotra, M.K. Mishra, “A supervisory power management system for a hybrid microgrid with HESS,” IEEE Transactions on Industrial Electronics, 64, 5, pp. 3640–3649, May 2017
(7) U. Manandhar et al., “Energy management and control for grid connected hybrid energy storage system under different operating modes,” IEEE Transactions on Smart Grid, 10, 2, pp. 1626–1636, Mar. 2019.
(8) L. W. Chong, Y.W. Wong, R.K. Rajkumar, D. Isa, “An optimal control strategy for standalone PV system with battery-super-capacitor hybrid energy storage system,” Journal of Power Sources, C, 331, pp. 553–565, Nov. 2016.
(9) W. Jing, C.H. Lai, W.S.H. Wong, M.L.D. Wong, “A comprehensive study of battery-super-capacitor hybrid energy storage system for standalone PV power system in rural electrification,” Applied Energy, 224, pp. 340–356, Aug. 2018,
(10) S.K. Kollimalla, M.K. Mishra, L.N.N, “A new control strategy for interfacing battery supercapacitor storage systems for PV system,” 2014. Accessed: Apr. 21, 2022. [Online]. Available: https://ieeexplore.ieee.org/document/6804478/
(11) 11.B.R. Ravada, N.R. Tummuru, “Control of a supercapacitor-battery-PV based stand-alone dc-microgrid,” IEEE Transactions on Energy Conversion, 35, 3, 2020, Accessed: Apr. 21,