Over the coming years it is expected that considerably more wind power will be connected to the Irish power system. This will result in a power system that at times of high wind power penetration will operate with very low inertia, making the system susceptible to large rate of change of frequency (RoCoF) events due to disturbances. These high RoCoF events could result in the cascade tripping of generators connected to the grid resulting in complete shutdown of the system. This paper investigates the differences between local RoCoFs seen at individual buses and system wide RoCoFs seen across the entire power system. A model of the IEEE 39 bus power system was implemented and simulated with Power Systems Simulation for Engineers (PSS/E). Matlab was then used to process and analyse the results. The simulations and results show that after a disturbance on a power system, local RoCoFs close to the disturbance could occur that are significantly larger than the system RoCoF and predicted RoCoF.
"Investigation into the Local Nature of Change of Frequency in Electrical Power Systems,"
Student Journal of Energy Research:
1, Article 3.
Available at: http://arrow.dit.ie/sjer/vol2/iss1/3