When operating with a shunt or AREP excitation, the power supply voltage depends on the voltage at the terminals of the alternator. As a result, it can fluctuate with the load and therefore influence the PID's behavior and ultimately the voltage stability.
The function "VBus compensation" is intended to compensate these fluctuations by a self adaptation of the global PID loop Gain.
For example the graph highlights the voltage build-up with and without compensation in the case of a shunt excitation.
