GB983265A - Arrangement for regulating the voltage or reactive power of synchronous generators - Google Patents

Abstract

983, 265. Automatic control. SIEMENS-SCHUCKERTWERKE A.G. Sept. 5, 1962 [Sept. 6,1961 ], No. 34096/62. Heading G3R. In an arrangement for controlling the voltage or reactive power of a synchronous machine 1, Fig. 1, supplying a system 4 through a transformer 3 an exciter 2 is controlled through a variable amplifier 7 by an error signal from a comparator 6. The comparator is fed with an input signal, from an element 5, dependent on the rotor angle defined as the angle between the instantaneous angular position of the rotor and one of the vectors of the supply voltage, and a reference input signal from a slider of a potentiometer 8 positioned by a servomotor 9. The servomotor 9 is energized from a regulator 10, Fig. 2, in dependence on the difference between the actual line voltage, or reactive power, V and a desired valve pre-set by the tension F of a spring (not shown). To prevent the rotor angle exceeding a value determined by the transient stability limit of the machine a polarized relay 13 opens the circuit of the servomotor when the slider voltage exceeds a voltage, across a resistor 14, dependent on the real power or current supplied by the machine as determined by a device 11. When the output of the regulator 10 is such as to lower the reference input signal a winding 15 of the relay causes the servomotor to be reconnected to the regulator 10.