【摘要】 在电力变压器保护过程中,励磁涌流可能导致大型变压器差动继电保护误动作,为了解决此问题,从变压器电磁特性出发,以电流和电压两个暂态变量为基础,提出了利用主侧和二次侧绕组的感应电压比来实现变压器继电保护的方法。整个大型变压器保护系统以DSP为内核,采样信号经DSP判断处理后经过光电隔离输出给保护设备,后台软件控制保护设备动作,从而实现对大型变压器的保护。新判据能够快速可靠地判别变压器内部故障电流和励磁涌流;出口动作具有较高的可靠性和时效性。更多还原

【Abstract】 In the process of power transformer protection, differential relays of a large transformer are prone to maloperation during magnetic inrush.In order to solve this problem,setting out from the transformer electromagnetism characteristic,using the two transient variable of current and voltage,the paper proposes a transformer protective relaying algorithm using the ratio of induced voltages of the primary and secondary windings.Taking DSP as the inside core,backstage software control the act of the protection equipments by the sampling signal which flows from DSP to photoelectrical insulation.Thus the large transformer protection achieves.New criterion can distinguish internal fault current from magnetic inrush quickly and reliably acts of export are dependable and effective.更多还原