Seg HighTECH MRG3 - Measuring Principle of Vector Surge Supervision

SEG Electronics GmbH Manual MRG3
26 DOK-TD-MRG3, Rev. D
4.5.3 Measuring principle of vector surge supervision
When a synchronous generator generates power, the so-called rotor displacement angle is built
between the terminal voltage (mains voltage U1) and the synchronous internal voltage (Up). This
rotor angle produces a voltage difference U is built between Up and U1 (Fig. 4.4).
Figure 4.4: Equivalent circuit for synchronous generators running in parallel with the mains
Figure 4.5: Changement of the rotor displacement angle at sudden load of the generator
The rotor displacement angle between stator and rotor is depending on the mechanical moving
torque of the generator shaft. The mechanical shaft power is balanced with the electrical fed mains
power, and therefore the synchronous speed keeps is maintained
(Fig. 4.5).