Control and Design of Microgrid Components - Power Systems ...

Figure 7.11 Actual Grid Frequency Samples.
Figure 7.12 Impact on the Power Setpoint of a Frequency Deviation of 0.05 Hz.
The voltage also fluctuates of nearly 0.6 V in either direction. The setpoint of 208V is to be
intended “on the average”. The frequency and voltage fluctuations combined determine
conditions of non-repeatability on any of the following grid connected waveforms. Different
values of frequency will determine different power injections (and the following plots are
recording the actual grid frequency), while different voltages at the point of connection will
determine different reactive power injections. Although none of these differences are
outstanding, the fact that they exist must not be forgotten when trying to reproduce “exactly”
these same results.
The load active power demand is 0.3 pu for every load. But this number does not include the
losses in the network. The same load, when fed from a neighboring source has a demand of 0.3
100