The experimental results are given in Fig. 7. The generator
is synchronized to the microgrid in t1. Before t1, no active
power flows through the line. The angle difference has a nonzero
derivative as the output voltage frequency of the
generator differs from the one of the micro grid. After t1, the
active power converges to operation at quasi no active power
flow. The mechanical power is then varied in t2, t3 and t4. Note
that the increase is not a step as the armature voltage of the
DC machine can be continuously varied by rotating the
actuator. In the new stable situations reached after t2 and t3,
angle difference and active power could be determined
through load flow equations. The increase of power at t4 leads
to generator’s breakdown.
Figure