VOLTAGE REGULATION 



A dial switch is provided by which the strength of the alternating- 

 current control magnet may be varied and the regulator made to 

 compensate for any desired line drop up to 15 per cent, according 

 to the line requirements. 



This arrangement is very satisfactory for general use but where 

 the power-factor of the load has a wide range of variation, as in 



Main Contacte Compensating 

 Winding 



D.C. 

 Control 

 Magnet 



FIG. 221. Connections for Line Drop Compensator. 



transmission lines, better results can be obtained with a special 

 line drop compensator, adapted to the regulator. This compen- 

 sator (see diagram Fig. 221), has two dial switches which are con- 

 nected to a number of taps of a resistance and a reactance coil, so 

 that the value of these can be adjusted to compensate accurately 

 for line losses with loads of varying power-factor. 



KR System of Regulation. This system is particularly 

 adapted to plants where it is necessary to maintain a constant 

 exciter voltage as in cases where it is desirable to operate motors 

 and other auxiliary station apparatus from the exciter bus. This 

 system also permits of the use of a storage battery in multiple 

 with the main exciters. 



By referring to Fig. 222 it will be noted that there is a third 

 bus employed and a D.C. booster connected between this bus and 

 one of the exciter busses. The main generator fields then are 

 connected across the outside bus, the voltage of which is deter- 

 mined by the voltage of the booster. This booster is usually 

 excited from a separate exciter whose field is connected from the 

 neutral of the above-mentioned battery and the neutral of a set 



