If resistance is ignored, at what power angle does the maximum theoretical MW flow occur?

The maximum theoretical MW flow in an AC power system occurs at a power angle of 90 degrees. This is derived from the relationship between power flow and the power angle in the context of synchronous machines.

In an AC system, the real power (MW) transfer between two synchronous generators or between a generator and a grid can be described by the formula:

[ P = \frac{V_1 V_2}{X} \sin(\delta) ]

In this equation, (P) is the real power flow, (V_1) and (V_2) are the voltage magnitudes of the systems, (X) is the reactance between the two systems, and (\delta) is the power angle (the angle difference between the voltages of the two systems).

As this equation shows, the power flow is proportional to the sine of the power angle. The sine function reaches its maximum value of 1 at an angle of 90 degrees. Therefore, when the power angle reaches 90 degrees, the maximum theoretical MW flow occurs.

At angles greater than 90 degrees, the power flow starts to decrease, moving towards zero at 180 degrees. Thus, while the flow is maximum at