TY - JOUR
T1 - Coordinated VSG Control of Photovoltaic/Battery System for Maximum Power Output and Grid Supporting
AU - Liu, Yonghui
AU - Wang, Yue
AU - Wang, Minghao
AU - Xu, Zhao
AU - Peng, Yang
AU - Li, Mingxuan
N1 - Funding Information:
This work was supported in part by the Natural Science Foundation of China (NSFC) under Grant 51777159, in part by HK PolyU Research Institute for Smart Energy (RISE) under Strategic Supporting Scheme under Grant P0039642, and in part by the Fundamental Research Funds for the Central Universities under Grant xzy022019035.
Publisher Copyright:
© 2022 IEEE.
PY - 2022/3/1
Y1 - 2022/3/1
N2 - In a two-stage photovoltaic (PV) system, batteries are generally connected to the DC-link via a converter for buffering the power imbalance induced by the grid supportive services of grid-side inverter and the maximum power point tracking (MPPT) of PV source. Considering the limited battery capacity, the MPPT operation is easily compromised to avoid over-energizing the batteries in the conventional virtual synchronous generator (VSG) control, degrading the energy efficiency and extending the payback period. To concurrently achieve grid supporting and maximum PV power harvesting without increasing batteries, a coordinated VSG control for the photovoltaic/battery (PV/Bat) system is proposed in this paper. In the proposed strategy, the DC-link voltage level is segmented to differentiate the operations of converters. When the DC-link voltage is within the safety margin, the PV source operates at MPPT mode and the inverter output frequency is programmed proportionally to the DC-link voltage deviation. Meanwhile, droop control is implemented to associate the battery power with the DC-link voltage. When the DC-link voltage goes beyond the safety margin, PV de-loading and inverter rectification will be adaptively activated to restore DC-link voltage within the predefined range. The effectiveness and advantages of the proposed strategy are eventually verified by simulations and experiments.
AB - In a two-stage photovoltaic (PV) system, batteries are generally connected to the DC-link via a converter for buffering the power imbalance induced by the grid supportive services of grid-side inverter and the maximum power point tracking (MPPT) of PV source. Considering the limited battery capacity, the MPPT operation is easily compromised to avoid over-energizing the batteries in the conventional virtual synchronous generator (VSG) control, degrading the energy efficiency and extending the payback period. To concurrently achieve grid supporting and maximum PV power harvesting without increasing batteries, a coordinated VSG control for the photovoltaic/battery (PV/Bat) system is proposed in this paper. In the proposed strategy, the DC-link voltage level is segmented to differentiate the operations of converters. When the DC-link voltage is within the safety margin, the PV source operates at MPPT mode and the inverter output frequency is programmed proportionally to the DC-link voltage deviation. Meanwhile, droop control is implemented to associate the battery power with the DC-link voltage. When the DC-link voltage goes beyond the safety margin, PV de-loading and inverter rectification will be adaptively activated to restore DC-link voltage within the predefined range. The effectiveness and advantages of the proposed strategy are eventually verified by simulations and experiments.
KW - grid supporting
KW - maximum power output
KW - photovoltaic/battery (PV/Bat) system
KW - Virtual synchronous generator (VSG)
UR - http://www.scopus.com/inward/record.url?scp=85123369792&partnerID=8YFLogxK
U2 - 10.1109/JETCAS.2022.3143716
DO - 10.1109/JETCAS.2022.3143716
M3 - Journal article
AN - SCOPUS:85123369792
SN - 2156-3357
VL - 12
SP - 301
EP - 309
JO - IEEE Journal on Emerging and Selected Topics in Circuits and Systems
JF - IEEE Journal on Emerging and Selected Topics in Circuits and Systems
IS - 1
M1 - 9682750
ER -
