I am modeling a microgrid power system with one synchronous generator (SimPowerSystems non-linear block) and one 3-phase inverter-based source. The inverter is modeled as 3 individual controlled voltage sources. I would like to use the power flow tool to generate initial conditions to initialize the controllers for the generator and the inverter. However, I can't use the power flow tool with the 3-phase inverter represented by individual controlled voltage sources. How can I specify the inverter bus as a PV bus without using a 3ph controlled voltage source? (a 3ph voltage source block isn't available where I can manipulate voltage magnitude and frequency) Can I somehow use the single-connector Load Flow Bus block for this? Or is that block type only to display power flow values from buses falling under machine or 3ph controlled source category? See attached image of how I am modeling the inverter if helpful.