

Using our notation we might call it a dV bus. This bus has a fixed voltage magnitude and voltage angle.

Again this is because the equations are the summation of real power (P) and an equation for Voltage = Setpoint (V).

PV: a bus that has a generator at it which is regulating the terminal voltage to a voltage setpoint will be called a PV bus.We call them a PQ bus because we use the equations for summation of real power (P) and reactive power (Q) at these buses and the unknown variables are then voltage angle (V) and voltage angle ( d). PQ: buses that have no voltage control devices such as a generator at them and are also not remotely controlled by a generator will be called a PQ bus.The following BusCat strings are the standard one seen for generators and switched shunts using local voltage control as described in the Power Flow: Bus Equation Basics topic. This is a comprehensive list of the potential string that will appear in this field and what they mean. The various topics on the Power Flow Theory all end up describing different possibilities for the field that appears in the mismatch table called "Type" or "BusCat".
