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DOE OSTI · 2305667

Switching-cycle-based Startup for Grid-connected Inverters

He, Yuchen·Li, Yuan·Zhou, Bokang·Peng, Fang Zheng
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Abstract

Conventional inverter startups, or grid synchronization, are hindered by slow dynamics and inrush current issues, which impede the integration of more renewable energy resources into the power grid. This paper overcomes the barriers by introducing a novel switching cycle-based startup approach for grid-connected inverters, eliminating the need for voltage sensors and phase-locked loops (PLLs). The proposed method surpasses the bandwidth constraints of traditional PLL-based techniques and achieves grid synchronization in just two switching cycles. Relying solely on sensed three-phase currents, synchronization is accomplished without inrush currents or the need for additional hardware or increased software complexity, resulting in a faster inverter startup. The paper also presents a sensitivity analysis to discuss the impact of critical parameters on the method's accuracy. As a result, the effectiveness of the proposed technique is demonstrated through simulation and experimental results.

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14 SOLAR ENERGY24 POWER TRANSMISSION AND DISTRIBUTION25 ENERGY STORAGEGrid-tied invertersGrid-tied inverters, phase-locked loop (PLL) less, startup, voltage sensorless control.PLL-lessVoltage sensorless controlstartup

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He, Yuchen, Li, Yuan, Zhou, Bokang, Peng, Fang Zheng. 2024-02-12. Switching-cycle-based Startup for Grid-connected Inverters. https://doi.org/10.1109/jestie.2024.3365031

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