大型发电机转子电压二次回路设计

为了确保大型发电机转子回路及相连二次设备的绝缘安全,总结了当前转子电压二次回路设计的现状,并结合工程实际和相关设计规程,考虑转子绕组回路可能出现的过电压,给出了转子电压二次回路的推荐设计方案,转子电压经分压器转接或变送器隔离引出,供故障录波器和失磁保护接入,而转子接地保护则就地安装。通过在某700MW水电机组上的应用实践证明,采用推荐方案既可满足保护和故障录波器等二次设备的要求,又兼顾了一次系统的安全,且节省了投资,具有实用价值。

Design of Secondary Circuit of Rotor Voltage for Large-scale Generator

In order to guarantee the insulation and safety of the circuit of rotor and its' linked equipment such as relay protection and etc.,this paper summarizes the present situation of the secondary circuit of rotor voltage for large-scale generator,and analyzes the merits and demerits. With consideration of the practical engineering,the related design standards and the over-voltage in the secondary circuits of the rotor voltage,a suggested proper scheme of the secondary circuit is given in the paper,that is the rotor voltage switch-in the fault recorder or loss of excitation protection is isolated by transducer or reduced by voltage divider,the rotor earthing fault protection mounted on site. The suggested scheme has practical value because it does not only consider the requirements of relay and fault recorder,but also secures the safety of the primary system. Furthermore,it reduced the investment on electric cable. The application on LongTan's 700MW hydraulic generator has proved that it is practical.