农村小水电站的发电机大多采用半导体整流励磁,其中尤以双绕组电抗分流、三次谐波励磁使用广泛。这种发电机单独运行时,励磁装置能随着发电机负载电流的变化而改变励磁电流。藉此维持发电机的端电压稳定。但是,并入大电网后,情况就不同了。 Most of the generators used in rural small hydropower stations adopt semiconductor rectifier excitation, especially in the case of double winding reactance diversion and the third harmonic excitation is widely used. When this generator is operated alone, the excitation device can change the excitation current as the generator load current changes. This maintains the terminal voltage of the generator stable. However, the situation is different when it is incorporated into the grid.