汽轮发电机励磁绕组短路多回路数学模型及电感系数

Multi-loop Mathematical Model and Inductance of Turbo-generator with Field Winding Inter-turn Short Circuits

为了用数值仿真方法研究大型汽轮发电机励磁绕组匝间短路故障机理,依据多回路方法提出了回路选取原则,据此选取各回路及其独立变量,形成了联无穷大电网时汽轮发电机励磁绕组匝间短路多回路数学模型;用气隙磁导法推导了单个线圈间电感系数的计算公式,并得到了数学模型中定子绕组各支路自感及其间互感,阻尼绕组各回路自感及其间互感,定子绕组各支路与阻尼绕组各回路间互感,励磁绕组各回路自感及其间互感,定子各支路与励磁各回路间互感,励磁绕组各回路与阻尼绕组各回路间互感系数的计算公式。通过对绕组正常时参数对比和励磁绕组匝间短路时仿真和实验结果的对比,表明了回路选取、数学模型和电感系数计算公式的正确性。

In order to analyze the fault feature of large turbo-generator with field winding short circuits in simulation method,the loop selecting principle was introduced in multi-loop method,and the multi-loop mathematical model of turbo-generator with field winding short circuits under infinite network load was established.In air-gap permeance method the single coil＇s inductance was deduced,the inductance formulas in the model were given as follows：stator winding branch＇s self-mutual inductance,damping winding loop＇s self-mutual inductance,mutual inductance between stator winding branch and damping winding loop,field winding loop＇s self-mutual inductance,mutual inductance between stator winding branch and field winding loop,and mutual inductance between field and damping winding loop.The mathematical model and inductance formulas were verified by comparison of inductance results and by the simulation and experiment results under the short circuit fault.