发电机投电制动时转子过电压分析  

Analysis of the Overvoltage of Generator Rotor during Electric Braking

作　　者：廖慧敏 LIAO Huimin(State Grid Hubei Huanglongtan Power Plant, Shiyan 442000, China)

机构地区：[1]国网湖北黄龙滩电厂,湖北十堰442000

出　　处：《水电与新能源》2021年第12期61-63,共3页Hydropower and New Energy

摘　　要：发电机转子过电压容易破坏发电转子绝缘,影响发电机的正常运行,所以应在满足规范情况下,尽可能降低发电机转子过电压定值,保证发电机转子绝缘不受伤害。由于电制动短路开关投入瞬间三相不一致产生零序电流,在投入电制动短路开关之前,在转子两侧接入一氧化锌阀片400 V(转子额定电压为296 V),电制动整体退出时将这一氧化锌阀片退出,这样既保护了转子,又不影响电制动的正常投入。Overvoltage of the generator rotor could damage the insulation of the rotor and affect the normal operation of the generator.Thus,the overvoltage setting of the generator rotor should be reduced as much as possible while still fulfilling the specification requirements to ensure that the insulation is not damaged.At the moment when the electric braking short-circuit switch is closing,the inconsistency among the three phases could produce zero sequence current.Therefore,before the closing of the electric braking short-circuit switch,a 400 V zinc-oxide valve plate(the rated voltage of the rotor is 296 V)is connected on both sides of the rotor.When the whole electric braking is withdrawn,the zinc-oxide valve plate should be withdrawn also.The proposed measurement not only protects the rotor,but also does not affect the normal operation of the electric braking.

关 键 词：电制动 转子过电压 跨接器 励磁系统 氧化性阀片 

分 类 号：TM312[电气工程—电机]