Power-system transients

V. Karapetoff. The method of solution of the problem of power surges, developed by the authors, may be called that of solution of differential equations by finite increments. While in the paper the differential equations themselves are not written down explicitly, they are understood to hold true. These equations express the condition that an excess of mechanical energy, applied to a synchronous machine, partly accelerates (or retards) its revolving masses, partly is delivered to the bus through a change in the torque angle, and the rest is delivered to the bus through the asynchronous action of the damper winding2.