公开(公告)号：US4118749A

公开(公告)日：1978-10-03

申请号：US782745

申请日：1977-03-30

申请人： Takeshi Matuzaki ,  Masuo Goto ,  Yasushi Momochi

发明人： Takeshi Matuzaki ,  Masuo Goto ,  Yasushi Momochi

IPC分类号： H02P9/30 ,  H02H7/08 ,  H02H7/09

CPC分类号： H02H7/0805

摘要： An apparatus for protecting a synchronous machine from a field overvoltage is disclosed. The apparatus comprises a field excitation control circuit which is impressed with the armature voltage of the synchronous machine so as to provide a DC power supply for producing a DC output to excite the field winding of the synchronous machine, a first discharge circuit which is adapted to discharge the stored energy of the field winding when the synchronous machine is to be tripped under predetermined conditions, and a second discharge circuit for reducing the field voltage by allowing a field current to flow therethrough in response to generation of an overvoltage whose absolute value is higher than a predetermined level, across the field winding. The resistance of the second discharge circuit is selected to be higher than that of the first discharge circuit so that even in the presence of an overvoltage across the field winding, the overvoltage is suppressed by the second discharge circuit thereby to prevent frequent tripping of the synchronous machine due to overvoltage.

摘要翻译： 公开了一种用于保护同步电机免受场过电压的装置。 该装置包括励磁励磁控制电路，其被同步电机的电枢电压施加，以便提供用于产生用于激励同步电机的励磁绕组的DC输出的DC电源;第一放电电路， 当同步电机在预定条件下跳闸时，放电励磁绕组的存储能量;以及第二放电电路，用于通过允许场电流响应于其绝对值较高的过电压的产生而流过其中来减小励磁电压 超过预定水平，跨过场绕组。 第二放电电路的电阻被选择为高于第一放电电路的电阻，使得即使在场绕组上存在过电压的情况下，也可以通过第二放电电路抑制过电压，从而防止频率跳闸 机器由于过电压。