TY - GEN
T1 - A Novel Online Grid Impedance Measurement Method Based on Injecting Third Harmonic Voltage
AU - Cheng, Yanqi
AU - Wu, Weimin
AU - Orabi, Mohamed
AU - Eftychios, Koutroulis
AU - Chung, Henry
AU - Blaabjerg, Frede
PY - 2023
Y1 - 2023
N2 - Under grid-connected conditions, the adaptive control of the inverter can improve the stability of the system, as long as the grid impedance can be detected online quickly and accurately. The demerits of traditional active grid impedance measurement methods are complex data acquisition and processing, usually involving discrete Fourier transform (DFT), and the injected interference may deteriorate the power quality. In order to reduce the amount of calculation and minimize the impact on the operation of the inverter, this paper proposes to intermittently inject three cycles of the third harmonic signal into the inverter. Then the current and voltage variations at the point of common coupling (PCC) can be extracted through the Kalman filter, and the grid impedance can be estimated. The proposed method alleviates the total harmonic distortion produced by the continuous signal injection in the existing method, reduces the calculation amount and improves the detection speed at the same time. Simulation and experimental results show the effectiveness of this method. © 2023 IEEE.
AB - Under grid-connected conditions, the adaptive control of the inverter can improve the stability of the system, as long as the grid impedance can be detected online quickly and accurately. The demerits of traditional active grid impedance measurement methods are complex data acquisition and processing, usually involving discrete Fourier transform (DFT), and the injected interference may deteriorate the power quality. In order to reduce the amount of calculation and minimize the impact on the operation of the inverter, this paper proposes to intermittently inject three cycles of the third harmonic signal into the inverter. Then the current and voltage variations at the point of common coupling (PCC) can be extracted through the Kalman filter, and the grid impedance can be estimated. The proposed method alleviates the total harmonic distortion produced by the continuous signal injection in the existing method, reduces the calculation amount and improves the detection speed at the same time. Simulation and experimental results show the effectiveness of this method. © 2023 IEEE.
KW - grid impedance
KW - harmonic
KW - inverter
KW - real-time estimation
UR - http://www.scopus.com/inward/record.url?scp=85182932434&partnerID=8YFLogxK
UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-85182932434&origin=recordpage
U2 - 10.1109/ECCE53617.2023.10362200
DO - 10.1109/ECCE53617.2023.10362200
M3 - RGC 32 - Refereed conference paper (with host publication)
SN - 979-8-3503-1645-2
T3 - IEEE Energy Conversion Congress and Exposition, ECCE
SP - 1253
EP - 1257
BT - 2023 IEEE Energy Conversion Congress and Exposition (ECCE)
PB - IEEE
T2 - 2023 IEEE Energy Conversion Congress and Exposition (ECCE 2023)
Y2 - 29 October 2023 through 2 November 2023
ER -