Analysis of real time frequency transients and inertia estimation of Bangladesh power system

This paper presents observations of real time frequency transients of Bangladesh Power System (BPS) including last country-wide blackout on 1st November, 2014 after HVDC station tripped with respect to frequency control and primary focus on Inertial Frequency Response. The inertia constant of a system describes the initial, transient, frequency behavior of a system when subjected to a real power disturbance. Therefore, the inertia constant of a system can be a useful tool when investigating the frequency stability of a system. The frequency transients of power system is a significant index for power system operation and research on the dynamic frequency characteristic of power system is the basis of many important design works such as the design of under frequency load shedding scheme. Therefore, it is of great urgency and necessity to analysis the dynamic frequency characteristic of BPS before countrywide blackout after disturbance. This paper first analysis two real time frequency transients those have almost similar pre-disturbance network condition and secondly shows that maintaining minimum level of Inertial reserve in real-time operations with unit commitment can be crucial to ensure stable, secure and reliable operation of BPS. Beside this under frequency scheme should be revised and controlled BPS network disintegration along with rate of change of frequency should be adopted for adaptive as well as self-healing of BPS. This paper also focus on adaptive central under frequency and under voltage load shed scheme (UFVLS) rather than discrete under frequency load shed (UFLS).