【摘要】 在工程应用中,传统的注入式定子接地保护方案经发电机中性点接地变压器二次侧注入和测量,受接地变压器参数影响很大,补偿不准确或回路参数变化会产生很大的测量误差,引起保护误动或拒动。文中简单介绍了传统注入式定子接地保护的原理,重点分析了接地变压器参数的影响,在原有保护方案的基础上,提出一种改进的无需阻抗补偿的保护方案。动模试验结果表明改进方案能满足保护误差要求,且能有效避免补偿不准确或设备参数变化带来的测量误差,提高了保护可靠性。更多还原

【Abstract】 In engineering applications,traditional injecting source-based stator ground fault protection that relays on injection and measurement at the secondary side of a grounding transformer is largely influenced by the parameters of the grounding transformer.Large measurement errors could be caused by inaccurate compensation or circuit parameter changes,and may lead to relay mal-operations or tripping failures.The scheme of traditional injecting source-based stator ground fault protection is introduced,and the influence of grounding transformer parameters is analyzed.An improved protection scheme that do not need impedance compensation on basis of traditional protection scheme is proposed as well.Test results from dynamic simulation verify that the improved scheme satisfies the demands of stator ground fault protection,avoids measurement errors caused by inaccurate compensation and circuit parameters change,and also increases the reliability.更多还原