This paper analyzes the forming process of unloading voltage and the relations among unloading voltage, phase electromotive force, exciting current and rotational speed in an alternator.

• 分析了变压器空载合闸时激磁电流和磁通瞬态过程 ,讨论了合闸时引起过电流保护装置动作的原因 ,并提出了解决方法。