Excitation-Rheostat
EEE
Excitation-rheostat is a type of variable resistor (rheostat) used within an electrical machine's excitation system to control the strength of the magnetic field, thereby regulating the output voltage and reactive power of synchronous or DC machines. By adjusting the rheostat's resistance, the flow of current to the field windings can be manually or automatically varied, which directly influences the machine's magnetic field and, consequently, its output.