This example shows the use of two Frequency (Phasor) blocks to measure the frequency variation in a network following a line outage.
The network that is represented corresponds to the Kundur's Four-Machine Two-Area Test System, well known to study low frequency electromechanical oscillations in large interconnected power systems.
In this example, two Frequency (phasor) blocks are used to measure the frequency variation at the B1 bus (Area 1) and B2 bus (Area 2) after the transmission line B is disconnected from the network. The two measured frequencies are compared to the average system frequency. We can observe that the frequency tends to stabilize to 60.14 Hz around 75 sec, where a simple frequency regulation is performed (in open-loop) by reducing the reference power of the machine M1 in the Area 1.