Commissioning experience of the 300 MW Thailand-Malaysia Interconnection project

The Thailand-Malaysia HVDC Interconnection is comprised of two 300 MW converter stations joined by a 110 km long 300 kV DC transmission line. The system provides for exchange of energy and peaking power between the two countries. Key technical features of the project include the use of DC active filters, triple tuned AC filters, point on wave switching of AC filters and transformers, optical DC current and voltage measurement and a full length neutral conductor on the DC line. Commissioning of the system commenced in November of 2000 with system testing being conducted from April to September 2001. The system tests proved the performance of the interconnection and verified that key specification criteria had been met. While conducting these tests, a number of incidents occurred which uncovered problems involving the interaction of the DC system with the AC systems of the two countries. Further study and analysis is required in order to establish the exact cause of these problems and identify possible solutions.