Sungrow has announced the successful grid connection and completion of full acceptance testing for the Cambodia EDC Kandal Stueng station (GS79), a 108.4 MW/215.6 MWh battery energy storage system (BESS) in Takmao, Kandal Province.
The project deploys grid-forming technology at utility scale and is designed to support grid stability, black-start capability, and coordination with hydroelectric and thermal generation. The facility is located at a key point in Cambodia’s central power grid, including transmission corridors that import electricity from Vietnam.
During system-restoration testing, 516 grid-forming power conversion system (PCS) units successfully energized the entire BESS plant from zero voltage while establishing stable voltage and frequency.
The system also supported the energization of approximately 240 km of transmission lines and five substations as the network was progressively restored.
As part of the testing, the BESS supported the startup and synchronization of the 60 MW Kamchay Hydropower Plant. The restored network was subsequently operated with the 135 MW CIIDG coal-fired power plant, the energy storage system, and connected loads.
The project remained stable during five transformer energization events, including one involving a transformer rated at up to 100 MVA. It also maintained stable operation while synchronizing different power sources with a phase-angle difference of up to 15 degrees.
The BESS demonstrated extended islanded operation for 3.5 hours, allowing it to continue supporting the local network while separated from the main grid. The project also completed three transitions between grid-connected and islanded modes, with voltage deviation maintained below 2% and transient frequency fluctuations within 0.15 Hz during grid separation.
Sungrow said the project was delivered under strict testing requirements, a compressed construction schedule, and rainy-season conditions with ambient temperatures reaching 40°C.
The commissioning and testing activities were completed within 20 days. The project team carried out hot commissioning and three rounds of performance testing during the commissioning period to support timely grid connection.
Sungrow provided services covering storage and monitoring system design, equipment design, commissioning, EPC-related support, and operations and maintenance. The company said the integrated approach was intended to address the project’s grid-level requirements across design, delivery, and operation.
The project adds a large-scale grid-forming BESS installation to Cambodia’s power system and demonstrates the use of energy storage for grid restoration, islanded operation, and coordination with multiple generation sources.
Discover more from SolarQuarter
Subscribe to get the latest posts sent to your email.
