发电机误上电保护新型主判据研制

A Novel Main Criterion for Generator Inadvertent Energizing Protection

提出并论证发电机误上电保护扇形低阻抗新型主判据及其整定计算,分析发电机在不同工况下误上电时电机有功功率及保护安装点测量阻抗的不同特性,得出发电机误上电初始测量阻抗在R-X平面4个象限的任1个或2个象限中波动皆有可能的结论。扇形低阻抗特性的误上电保护在R-X平面4个象限中都具有足够大的动作区,它既能保证发电机正常并网时可靠不动作,又能保证发电机在停机及正常并网的启动过程中任一时刻误上电时,该保护都能高灵敏地动作。所研制的保护已投入运行。

A novel main criterion for generator inadvertent energizing protection using the fan-shaped tow impedance principle and its setting calculation method are proposed. When inadvertent energizing happens under different operating conditions, different characteristics of generator active power and measuring impedance at the protection installation point are analyzed. It can be concluded that the measuring impedance may fluctuate in any one or two of the four quadrants of the R-X plane at the initial moment of the inadvertent energizing. The generator inadvertent energizing protection using the fan-shaped low impedance principle has a large enough action area in each of the four quadrants of the R-X plane. It can not only reliably prevent the misoperation of the protection equipment when the generator is connected to the grid normally, but also can ensure highly sensitive tripping when inadvertent energizing happens any time of the stop or start process. The protection equipment using the novel criterion has been put into operation.