TY - JOUR
T1 - Secondary Frequency Support to Weak Grids through Coordinating Control of Hybrid HVDC System
AU - Kaur, Jagdeep
AU - Chaudhuri, Nilanjan Ray
N1 - Funding Information:
Manuscript received May 25, 2019; revised September 9, 2019; accepted October 21, 2019. Date of publication October 28, 2019; date of current version July 23, 2020. This work was supported by the National Science Foundation under Grant ECCS 1656983. Paper no. TPWRD-00568-2019. (Corresponding author: Nilanjan Ray Chaudhuri.) The authors are with the School of Electrical Engineering and Computer Science, Pennsylvania State University, University Park, PA 16802 USA (e-mail: juk415@psu.edu; nuc88@psu.edu).
Publisher Copyright:
© 1986-2012 IEEE.
PY - 2020/8
Y1 - 2020/8
N2 - A recently proposed Hybrid-High Voltage DC (HVDC) system comprising a Capacitor Commutated Converter connected in series with a 2-stage Voltage Source Converter called 'Vernier' on the DC side and in parallel on the AC side is considered to transfer power from onshore wind farms (WFs) to the load centers. The flexible DC voltage polarity of the Vernier gives rise to circulating power. Although the circulating power leads to unwanted losses, it can be leveraged as an additional degree of freedom. This extra degree of freedom is used to provide secondary frequency control in the inverter-side grid by extracting power from the rectifier without any communication of signals while maintaining constant margin angle and firing angle at the respective ends. Moreover, to improve the rectifier-side grid frequency, the WFs provide primary frequency support while operating under deloaded condition. Analytical insight into this complex system is developed to damp frequency oscillations and increase utilization of Vernier capacity.
AB - A recently proposed Hybrid-High Voltage DC (HVDC) system comprising a Capacitor Commutated Converter connected in series with a 2-stage Voltage Source Converter called 'Vernier' on the DC side and in parallel on the AC side is considered to transfer power from onshore wind farms (WFs) to the load centers. The flexible DC voltage polarity of the Vernier gives rise to circulating power. Although the circulating power leads to unwanted losses, it can be leveraged as an additional degree of freedom. This extra degree of freedom is used to provide secondary frequency control in the inverter-side grid by extracting power from the rectifier without any communication of signals while maintaining constant margin angle and firing angle at the respective ends. Moreover, to improve the rectifier-side grid frequency, the WFs provide primary frequency support while operating under deloaded condition. Analytical insight into this complex system is developed to damp frequency oscillations and increase utilization of Vernier capacity.
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U2 - 10.1109/TPWRD.2019.2949988
DO - 10.1109/TPWRD.2019.2949988
M3 - Article
AN - SCOPUS:85089348769
SN - 0885-8977
VL - 35
SP - 1685
EP - 1694
JO - IEEE Transactions on Power Delivery
JF - IEEE Transactions on Power Delivery
IS - 4
M1 - 8884729
ER -