Process for controlling isolated microgrids based on power-based control and modified volt-var function methods

A process for controlling isolated microgrids based on Power-Based Control and modified Volt-VAr function methods, the process comprising:

• a) identifying the range of power factor (PF) values for the microgrid to be controlled between the PF*min value and the PF*max value;
• b) in steady state, applying the power-based control method (PBC) via central controller (CC) and defining the references of PF to be used for the generators for the maximum value (PF*max) to control frequency inverters, (“variable frequency drive” or VFD) to inject reactive power according to calculated quantity (qref) via CC using the PBC method;
• c) identifying the moment in which the scheduled transitional regime will start;
• d) moments before the start of the scheduled transitional regime identified in step “c”, changing the PF references to be used for the generators to their minimum value (PF*min) and programming the VFDs to use the unit (unitary PF) as a reference, increasing its availability of reactive power exchange with microgrids within its technically specified limit;
• e) at the start of the programmed transitional regime, the CC commands are suspended and the VFDs start to define the power reactive exchanged with the grid autonomously depending on the voltage measured at its connection point using the modified Volt-Var curve, until the transitional regime ends;
• f) after the end of the transitional regime, the permanent regime condition described in step “b” is reestablished:
• the PBC control method via CC is reestablished, the PF references to be used for the generators return to the maximum value (PF*max) and the VFD inject reactive power (qref) calculated via CC by the PBC method.