TY - JOUR
T1 - A novel sliding mode observer-based compound sliding mode current control with active damping for single phase grid-tied inverter system in weak grid
AU - Teng, Qingfang
AU - Xu, Guorong
AU - Zheng, Xuewei
AU - Mai, Hao
AU - Ma, Xiping
AU - Wang, Yanbo
PY - 2022
Y1 - 2022
N2 - This paper proposes a novel sliding mode observer (SMO)-based compound sliding mode current control (CSMCC) strategy with active damping for the single-phase grid-tied inverter system in weak grid. To decrease the number of measurement sensors and thus reduce system cost, the SMO with rapid response and low chattering level is designed for estimating the inverter-side current and capacitor voltage of LCL-type filter, which is used for feedback control. To enhance robustness against the parameter variation of grid-tied inverter system, the CSMCC is put forward, which is composed of two parts. One part is the equivalent control for grid-tied inverter system with nominal parameters, and the other part is the reaching law-based second-order nonsingular terminal sliding mode control (NTSMC) for compensating the disturbance due to the parameter variations. Since an adaptive gain of switching function is employed and there is integral operation for this discontinuous switching function, the proposed NTSMC strategy not only speed up system response but also attenuate the system chattering level significantly. Moreover, for inhibition of inherent resonance resulting from LCL-type filter, the weighted average current-based active damping is used to provide feedback current for CSMCC. Comprehensive simulation and experimental results show that the proposed strategy can enable the grid-tied inverter system to not only have strong robustness against the filter parameters & grid impedance variations but also improve the quality of grid current, and have satisfactory suppression effect of background grid voltage harmonics on grid current.
AB - This paper proposes a novel sliding mode observer (SMO)-based compound sliding mode current control (CSMCC) strategy with active damping for the single-phase grid-tied inverter system in weak grid. To decrease the number of measurement sensors and thus reduce system cost, the SMO with rapid response and low chattering level is designed for estimating the inverter-side current and capacitor voltage of LCL-type filter, which is used for feedback control. To enhance robustness against the parameter variation of grid-tied inverter system, the CSMCC is put forward, which is composed of two parts. One part is the equivalent control for grid-tied inverter system with nominal parameters, and the other part is the reaching law-based second-order nonsingular terminal sliding mode control (NTSMC) for compensating the disturbance due to the parameter variations. Since an adaptive gain of switching function is employed and there is integral operation for this discontinuous switching function, the proposed NTSMC strategy not only speed up system response but also attenuate the system chattering level significantly. Moreover, for inhibition of inherent resonance resulting from LCL-type filter, the weighted average current-based active damping is used to provide feedback current for CSMCC. Comprehensive simulation and experimental results show that the proposed strategy can enable the grid-tied inverter system to not only have strong robustness against the filter parameters & grid impedance variations but also improve the quality of grid current, and have satisfactory suppression effect of background grid voltage harmonics on grid current.
KW - Weak grid
KW - Sliding mode observer
KW - Nonsingular terminal sliding mode control
KW - Active damping
KW - Grid-tied Inverter
UR - http://www.scopus.com/inward/record.url?scp=85126901009&partnerID=8YFLogxK
U2 - 10.1016/j.ijepes.2022.108117
DO - 10.1016/j.ijepes.2022.108117
M3 - Journal article
SN - 0142-0615
VL - 141
SP - 1
EP - 15
JO - International Journal of Electrical Power and Energy Systems
JF - International Journal of Electrical Power and Energy Systems
M1 - 108117
ER -