On October 18th, 2020, a Bengkulu power plant in Western Sumatra Island successfully deployed a Power System Stabilizer (PSS) System and completed leading phase tests for Unit #1 and Unit #2 Generators, first of its kind in Indonesia.
The success of this project is a milestone for Indonesian power industry. The State Grid Corporation of Indonesia (PLN) highly praised the accomplishments of the engineering firm contracted to perform this test using Crystal Instruments’ CoCo-80 analyzer, and later awarded the firm with long term contracts.
During the test, engineers optimized the PSS parameters and subsequently verified the effectiveness of the PSS during terminal voltage perturbation under 60 MW, 80 MW, 100 MW load conditions. In addition, one 150 kV line at an adjacent transformer substation was put out of service (fault free) to further confirm the effectiveness of the PSS during a local disturbance. The engineering team concluded that the low frequency oscillation is greatly offset by positive damping provided by the PSS system.
This high-profile coal-fired power plant located in Sepang Bay, Bengkulu Province, which took three years to build, entered commercial operations in early 2020. The total 2*100 megawatts (MW) capacity will not only power Sumatra’s western province but will also power nearby isolated regions.
“The US $360 million (Rp 5 trillion) power plant project is operated by privately owned power producer PT TenagaListrik Bengkulu (TLB) – a joint venture between PowerChina Resources (PCR), which is a backbone subsidiary controlled by PowerChina, and local heavy equipment distributor PT IntracoPenta (INTA)”, per The Jakarta Post.
The Bengkulu power plant was listed as one of Indonesia's key national projects in September 2020.
Power generation systems need to be designed to withstand large disturbances and maintain stability under changing operating conditions. Devices such as the generator automatic voltage regulator (AVR) and PSS are widely used to manage these system instabilities.
The PSS can improve oscillation stability, but it can also reduce transient stability by overriding the voltage signal to the exciter. The PSS must be tuned to provide the correct frequency-response characteristics.
The phase-frequency characteristics of the excitation control system should be determined with a signal analyzer. This information is used to configure the PSS settings.
The CoCo-80/80X product is one of the few analyzers certified to determine the phase-frequency characteristics of the excitation control system. The CoCo-80X is the upgraded hardware platform from CoCo-80 platform. Compared to the previous CoCo-80, the all new CoCo-80X boasts a powerful Dual-core processor and a 7” color display with touch screen.
The “Power System Stabilizer” application software in the CoCo-80X helps the PSS system to provide substantial phase shift to eliminate phase lag in the power system. Users can follow on-screen instructions to conveniently set up the connections during the test.
During the test, the coherences and Bode plots are measured and displayed. The performance of the PSS is verified using the CoCo-80X’s output channel to provide a Test Signal (white noise). A PSS test report will be generated at the end of testing.
For more information about the CoCo-80X and its capabilities, please contact info@go-ci.com.