TY - JOUR
T1 - Enhanced fault ride-through of power converters using hybrid grid synchronization
AU - Sahoo, Animesh
AU - Ravishankar, Jayashri
AU - Ciobotaru, Mihai
AU - Blaabjerg, Frede
PY - 2022/6
Y1 - 2022/6
N2 - Inaccurate phase-angle jump (PAJ) estimation of the grid voltage during faults is one of the major causes for poor fault ride-through (FRT) performance of converters. To overcome this issue and make the converter's current controller robust, this article proposes a hybrid grid synchronization transition technique. In this concept, a synchronous reference frame-based phase-locked loop (SRFPLL) grid synchronization method is used during normal grid operation and switched to an arctangent-based phase-angle estimation during grid faults. Simultaneously frequency estimation is switched to the arctangent derived frequency. A common transition method, which depends on the phase-angle error between the two-phase estimation techniques, is proposed to ensure a smooth transition between the hybrid phase-angle and frequencies. The transition technique is implemented using the current control of a three-phase voltage source converter in the SRF. The performance of the converter during both symmetrical and asymmetrical grid faults along with the FRT strategies is tested using real-time experiments. It is observed that the transition-based hybrid grid synchronization technique reduces the loss of synchronism duration. Additionally, it offers a more robust converter current control performance compared to the SRFPLL technique over a wide range of voltage sags and PAJs.
AB - Inaccurate phase-angle jump (PAJ) estimation of the grid voltage during faults is one of the major causes for poor fault ride-through (FRT) performance of converters. To overcome this issue and make the converter's current controller robust, this article proposes a hybrid grid synchronization transition technique. In this concept, a synchronous reference frame-based phase-locked loop (SRFPLL) grid synchronization method is used during normal grid operation and switched to an arctangent-based phase-angle estimation during grid faults. Simultaneously frequency estimation is switched to the arctangent derived frequency. A common transition method, which depends on the phase-angle error between the two-phase estimation techniques, is proposed to ensure a smooth transition between the hybrid phase-angle and frequencies. The transition technique is implemented using the current control of a three-phase voltage source converter in the SRF. The performance of the converter during both symmetrical and asymmetrical grid faults along with the FRT strategies is tested using real-time experiments. It is observed that the transition-based hybrid grid synchronization technique reduces the loss of synchronism duration. Additionally, it offers a more robust converter current control performance compared to the SRFPLL technique over a wide range of voltage sags and PAJs.
UR - http://www.scopus.com/inward/record.url?scp=85100514949&partnerID=8YFLogxK
U2 - 10.1109/JESTPE.2021.3054851
DO - 10.1109/JESTPE.2021.3054851
M3 - Article
SN - 2168-6777
VL - 10
SP - 2829
EP - 2841
JO - IEEE Journal of Emerging and Selected Topics in Power Electronics
JF - IEEE Journal of Emerging and Selected Topics in Power Electronics
IS - 3
ER -