ZHOU Yuhao,PENG Faxi,XIE Jianxiang,et al.Supercapacitor-based Inertia Emulation Control and Stability Improvement for Grid-forming Photovoltaic Inverter[J/OL].Automation of Electric Power Systems, http://dx.doi.org/10.7500/AEPS20250829009.
ZHOU Yuhao,PENG Faxi,XIE Jianxiang,et al.Supercapacitor-based Inertia Emulation Control and Stability Improvement for Grid-forming Photovoltaic Inverter[J/OL].Automation of Electric Power Systems, http://dx.doi.org/10.7500/AEPS20250829009.DOI:
Supercapacitor-based Inertia Emulation Control and Stability Improvement for Grid-forming Photovoltaic Inverter
With the increasing penetration of renewable energy in power systems
the inertia level of the power grid has been continuously decreasing
and the problems of system frequency and oscillation have become increasingly serious. To address the above challenges
this paper designs a supercapacitor-based inertia emulation control strategy by combining the power equations of the supercapacitor with the grid-forming matching control equations of the photovoltaic system. This strategy enhances system equivalent inertia without modifying the inherent grid-forming control architecture of the photovoltaic inverter. Furthermore
the equivalent torque method is employed to establish a stability analysis model
which clarifies the mechanisms of the influence of the DC-link voltage synchronization loop and the supercapacitor control loop on system stability. It reveals the mechanism of supercapacitor control suppressing low-frequency oscillations by enhancing damping torque in the low-frequency range
providing a theoretical foundation for control design. Finally
the proposed inertia analysis and emulation strategy is validated on the Typhoon hardware-in-the-loop test platform. The results show that the proposed strategy can effectively improve the inertia level and operational stability of the grid-forming photovoltaic inverter.
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