农村小水电站的三次谐波励磁发电机有时只能建立十几伏的空载电压,转速升高后,发电机的空载电压还是不能升高。此时,只需将发电机出线三相桩头短路一下(出现火花即可),发电机的空载电压就迅速升到400V。有时,发电机虽能建立起空载电压,但只有350～360V左右,总是达不到400V,检查励磁回路同 Third harmonic excitation generators in small hydropower stations in rural areas can only set up a no-load voltage of ten volts sometimes. After the speed increases, the no-load voltage of the generator can not be increased either. At this point, simply short-circuit the generator outlet three-phase pile (sparks can occur), the generator no-load voltage quickly rose to 400V. Sometimes, although the generator can establish no-load voltage, but only about 350 ~ 360V, always less than 400V, check the excitation circuit with