The First HVDC Project in Indonesia: System Study and Basic Design of Java-Sumatra HVDC Link

摘要

PT. PLN (Perseroan Terbatas Perusahaan Listrik Negara), state-owned utility company in Indonesia, is planning to construct its first HVDC link, connecting Java Island and Sumatra Island across the Sunda Strait.The HVDC transmission line consists of 369km of overhead lines in Sumatra side, 38km of submarine cables for crossing the strait, and 110km of overhead lines in Java side. Rating of the HVDC system is 3000MW, DC +/-500kV with bipolar, earth return scheme.The main purpose of the link is to establish reliable bulk power transmission from so-called “mine-mouth” coal-fired thermal power stations in Southern Sumatra to Java Island, in order to meet rapidly increasing power demand.Extensive system study had been carried out and basic design of the HVDC link was determined in accordance with the system study result. For instance, regarding HVDC system configuration, required system reliability was taken into account and impact on AC system caused by the HVDC operations, such as de-block/block were studied. Also, coordination control with AC system and overload capability were studied, and impact mitigation measure was proposed. Main equipment specifications were decided based on the system study result. SSTI (Sub-Synchronous Torsional Interaction) was also studied for Sumatra side AC system, and it was found there was a high possibility of occurrence of such interaction between HVDC and turbine generators in the coal-fired thermal power plants, and its countermeasure was proposed.In this paper, these system study and basic design of the project are described.