This example is the last step on the way 'from voltage source to generator model'.
Turbine and generator are packed into one single model. The terminal voltage depends on the line-properties. The correspondence is:
V_gen1.alpha0 - bus1.alpha_v ~ turboGen.generator.powerAngle V_gen1.v0 ~ exciter.v_f
See and compare for example:
sensor.p[1:2] active and reactive power V_gen1.alpha0 and busbar1.alpha_v with gen.powerAngle.