自耦补偿与谐波屏蔽换流变压器保护原理及判据整定

通过分析自耦补偿与谐波屏蔽换流变压器所具有的特殊的绕组布置与联结方式,阐述了基于变压器模型的新型换流变压器保护方案的基本原理.从该种变压器的基本数学模型出发,推导出了基于该原理的新型换流变压器的动作方程,拟订了该种变压器的保护方案并对判据加以整定.该判据通过比较所推导的动作方程两边的差值与所拟订的门槛值,用于可靠识别变压器内部故障.该保护方案摆脱了励磁涌流的影响,并且避开了变压器难以得到的内部参数.通过对该种变压器多种运行状态仿真计算验证了基于该保护方案的保护原理的正确性.

Protection principle of auto-compensator and harmonic shade converting transformer and its criteria setting

By analyzing the special winding layout and coupling mode of auto-compensator and harmonic shade converting transformer,the basic principle of protection scheme for new-type converting transformer based on the transformer model is expounded. Its action equation is deduced from its basic mathematics model and the criteria setting of protection scheme is given. The difference between two sides of action equation and the given threshold value are used to reliably identify the internal fault of transformers. The scheme gets rid of the influence of excitation inrush current and avoids the difficulty to get internal parameters of transformers. The simulative calculation of various transformer operating states,the correctness of the proposed scheme and its criteria are verified.