Robust model reference adaptive PI controller based sliding mode control for three-phase grid connected photovoltaic inverter

In this paper, the design of a new robust model reference adaptive PI (MRAC-PI) current controller is proposed for a two-stage grid connected photovoltaic (PV) inverter. Perturb & observe (P&O) algorithm is implemented in the boost part in order to extract the maximum power from the PV array. Firstly, the current dynamics with considering the system uncertainties are written in dq frame and are simplified by employing a decoupling system. Then, the MRAC-PI controller is designed based on a sliding mode control (SMC) to improve the robustness of the controller under system uncertainties. The parameters of PI controller are tuned based on SMC laws to track the desired reference model and provides fast and desirable dynamic response. The stability of the robust MRAC-PI is proven by using Lyapunov’s theory and Barbalet’s lemma. Finally, the performance of the proposed current controller and the conventional PI based voltage oriented control (VOC) during variations in filter inductance and solar irradiance are compared through simulation results. These results show the effectiveness of the proposed controller

PDF

___

1] Aourir M, Abouloifa A, Lachkar I, Aouadi C, Giri F et al. Nonlinear control and stability analysis of single stage grid-connected photovoltaic systems. International Journal of Electrical Power & Energy Systems 2020; 115: 105439. doi: 10.1016/j.ijepes.2019.105439
[2] Kabalcı E. Review on novel single-phase grid-connected solar inverters: circuits and control methods. Solar Energy 2020; 198: 247–274. doi: 10.1016/j.solener.2020.01.063
[3] Sampaio LP, da Rocha MV, da Silva SAO, de Freitas MHT. Comparative analysis of MPPT algorithms bio-inspired by grey wolves employing a feed-forward control loop in a three-phase grid-connected photovoltaic system. IET Renewable Power Generation 2019; 13 (8): 1379–1390. doi: 10.1049/iet-rpg.2018.5941
[4] Niazi K, Yang Y, Sera D. Review of mismatch mitigation techniques for PV modules. IET Renewable Power Generation 2019; 13 (12): 2035–2050. doi: 10.1049/iet-rpg.2019.0153
[5] Zeb K, Uddin W, Khan MA, Ali Z, Ali MU et al. A comprehensive review on inverter topologies and control strategies for grid connected photovoltaic system. Renewable and Sustainable Energy Reviews 2018; 94: 1120–1141. doi: 10.1016/j.rser.2018.06.053
[6] Zhu X, Chen K, Wang Y, Zheng H. Adaptive PID controller for cloud smart city system stability control based on chaotic neural network. Cluster Computing 2019; 22 (6): 13067-13075. doi: 10.1007/s10586-017-1197-5
[7] Pahari OP, Subudhi B. Integral sliding mode-improved adaptive MPPT control scheme for suppressing grid cur- rent harmonics for PV system. IET Renewable Power Generation 2018; 12 (16): 1904–1914. doi: 10.1049/iet- rpg.2018.5215
[8] Dang C, Tong X, Song W. Sliding-mode control in dq-frame for a three-phase grid-connected inverter with LCL- filter. Journal of the Franklin Institute 2020; 357 (15), 10159-10174. doi: 10.1016/j.jfranklin.2019.12.022
[9] Gao Y, Li X, Zhang W, Hou D, Zheng L. A sliding mode control strategy with repetitive sliding surface for shunt active power filter with an LCLCL filter. Energies 2020; 13 (7): 1740. doi: 10.3390/en13071740
[10] Yıldıran N, Tacer E. A new approach to H-Infinity control for grid-connected inverters in photovoltaic generation systems. Electric Power Components and Systems 2019; 1: 1–10. doi: 10.1080/15325008.2019.1689445 [11] Yang H, Zhang Y, Liang J, Liu J, Zhang N et al. Robust deadbeat predictive power control with a discrete time disturbance observer for PWM rectifiers under unbalanced grid conditions. IEEE Transactions on Power Electronics 2018; 34 (1): 287-300. doi: 10.1109/TPEL.2018.2816742
[12] Gholami-Khesht H, Monfared M, Taul MG, Davari P, Blaabjerg F. Direct adaptive current control of grid-connected voltage source converters based on the Lyapunov theorem. In: 2020 Ieee 9th International Power Electronics and Motion Control Conference (ipemc2020-ecce Asia); Tayland; 2020. pp.1-20.
[13] Shakeel FM, Malik OP. On-line self-tuning adaptive control of an inverter in a grid-tied micro-grid. Electric Power Systems Research 2020; 178: 106045. doi: 10.1016/j.epsr.2019.106045
[14] Raja BM, Houda R, Khadija D, Said NA. A discrete neuro sliding mode control with adaptive switching gain for uncertain nonlinear systems. In: 2018 15th International Multi-Conference on Systems, Signals & Devices (SSD); Hammamet, Tunisia; 2018. pp. 976–981. doi: 10.1109/SSD.2018.8570562
[15] Raja BM, Houda R, Khadija D, Said NA. A discrete adaptive second order neuro sliding mode control for uncertain nonlinear system. In: 2019 19th International Conference on Sciences and Techniques of Automatic Control and Computer Engineering (STA); Sousse, Tunisia, Tunisia; 2019. pp. 518–523. doi: 10.1109/STA.2019.8717283
[16] Tambara RV, Scherer LG, Gründling HA. A discrete-time MRAC-SM applied to grid connected converters with LCL-filter. In: 2018 IEEE 19th Workshop on Control and Modeling for Power Electronics (COMPEL); Padua, Italy; 2018. pp. 1–6. doi: 10.1109/COMPEL.2018.8460061
[17] Negi P, Pal Y, Leena G. Grid-connected photovoltaic system stability enhancement using Ant Lion optimized model reference adaptive control strategy. Differential Equations and Dynamical Systems 2020; 1: 1–23. doi: 10.1007/s12591-020-00525-9
[18] Elnady A, AlShabi M. Operation of parallel inverters in microgrid using new adaptive PI controllers based on least mean fourth technique. Mathematical Problems in Engineering 2019; 2019 (1). doi: 10.1155/2019/4854803
[19] Siddique AB, Munsi MS, Sarker SK, Das SK, Islam MR. Voltage and current control augmentation of islanded microgrid using multifunction model reference modified adaptive PID controller. International Journal of Electrical Power & Energy Systems 2019; 113: 492–501. doi: 10.1016/j.ijepes.2019.05.065
[20] Osório CR, Borin LC, Koch GG, Montagner VF. Optimization of robust PI controllers for grid-tied inverters. In: 2019 IEEE 15th Brazilian Power Electronics Conference and 5th IEEE Southern Power Electronics Conference (COBEP/SPEC); Santos, Brazil, Brazil; 2019. pp. 1–6. doi: 10.1109/COBEP/SPEC44138.2019.9065615
[21] Omar O, Ouassaid M. Power quality enhancement of grid-connected photovoltaic system using Fuzzy-PI control. In: 2018 International Symposium on Advanced Electrical and Communication Technologies (ISAECT); Rabat, Morocco, Morocco; 2018. pp. 1–6. doi: 10.1109/ISAECT.2018.8618807