Minimum SCR and Impact of PLL Gain on Flat Start Capability on a Point to Point VSC-HVDC Interconnection
Penulis/Author
Ir. Roni Irnawan, S.T., M.Sc., Ph.D., SMIEEE. (1); RIAN FATAH MOCHAMAD (2); Filipe Faria da Silva (3); Qi Zhang (4); Prof. Ir. Sarjiya, S.T., MT., Ph.D., IPU. (5)
Tanggal/Date
2023
Kata Kunci/Keyword
Abstrak/Abstract
This paper investigates the minimum grid
strength requirements to the interconnection between two
islands using HVDC, which are considered as weak or very weak
networks, e.g., Sumba and Sumbawa islands in Indonesia.
Renewable energy source power is transmitted from one island
to the other one through an HVDC interconnector. However, the
electricity network in the landing island is underdevelopment,
with non-uniform 70 – 150 kV long transmission lines between
generators and loads; therefore, its grid strength can be
considered weak or very weak grid depending on transferred
power. Simulations will consider different scenarios of power
transfer through the HVDC link. The minimum AC-side grid
strength in the form of short circuit rating (SCR) required to
achieve a flat start for each scenario is investigated. It is found
that minimum SCR is not constant, but rather follows a pattern
of the minimum SCR increasing linearly when the amount of
power transfer increases. It is also confirmed that the phase-
locked loop (PLL) plays an influential role in the
interconnection where a reduced proportional gain for the PLL
can turn a marginally unstable into a marginally stable system.
