The power angle in a power system is identified as which Greek letter?

The power angle in a power system is commonly represented by the Greek letter delta (Δ). This is due to its use in electrical engineering and power system analysis to denote the phase difference between the voltage at a generator and the voltage at a load or the system voltage.

In this context, delta is crucial as it helps in understanding how much power can be transferred through the lines and the stability of the system. The larger the delta, generally, the more power can be transmitted over a given impedance, up to the stability limit of the system. This relationship is pivotal in power system studies, particularly in analyzing oscillations, stability, and overall system performance. The other Greek letters mentioned do not have this specific association with power angles in electrical engineering, which further reinforces why delta is the recognized symbol for this concept.