The power angle curve, also known as the voltage angle curve, is an important concept in electrical engineering. It refers to the relationship between the power transmitted through a power system and the phase angle difference between the voltage and current waveforms. Synonyms for this term include the load angle curve, synchronous machine angle curve, and torque angle curve. Other related terms include the power-flow curve and the voltage-current curve. Understanding these concepts is essential for ensuring the stability and reliability of power transmission systems, and is important for anyone working in the field of electrical engineering.