Resonance Frequency Detection Technique in Gridconnected Inverter Systems Based on Double-order Digitalized Filter

Autor: Salaheddine Ethni, Volker Pickert, Hamza Khalfalla, Nasiru B. Kadandani
Rok vydání: 2019
Předmět:
Zdroj: 2019 10th International Renewable Energy Congress (IREC).
DOI: 10.1109/irec.2019.8754585
Popis: Voltage source inverters (VSI) employed in distribution generation systems are usually interfaced to the grid via a low-pass LCL filter. This filter has a resonance frequency peak which can vary with respect to grid impedance, leading to instability issues if not properly suppressed. This paper proposes a resonance detection method based on a double-order digital band-pass filter. The digital filter extracts only the harmonic components around the resonance frequency from the injected grid current waveform while attenuating other frequencies outside its passband. The range of resonance frequencies has been determined by a grid impedance estimation technique. The detection method has been implemented in an experimental single-phase grid-connected inverter system and the practical results validate the effectiveness of the proposed method.
Databáze: OpenAIRE