The legacy protection schemes face new challenges as the Inverter Interfaced Distribution Generation (IIDG) significantly changes the transient fault response of the distribution grid. The performance of the protection near the IIDG side is adversely affected by the Low Voltage Ride Through (LVRT) and the negative sequence current suppression control characteristics of the IIDG. The operational characteristics of that protection are very different from those of the legacy protection schemes used in the distribution grid. The traditional overcurrent protection schemes cannot meet the requirements of selectivity and sensitivity. In this paper, the influence of the IIDG on protection schemes used in the distribution grid is analyzed. Based on the positive sequence voltage polarization impedance criterion, a polarizing impedance criterion based on the fault component of positive sequence voltage, which can adaptively follow the fault resistance variation, is proposed to satisfy the requirements of grid operation. The simulation results show that: (a) the proposed criterion is immune to the adversely effects of the transient characteristics of the IIDG, and (b) it can adaptively follow the change of fault resistance which is suitable for the application in short distribution lines. Using the specialized System-on-Chip technology, a new distance protection device has been developed and tested on an industrial site. The new device for distance protection meets the requirements of the distribution grid with IIDGs.

随着逆变器接口配电网生成（IIDG）极大地改变了配电网的瞬态故障响应，传统的保护方案面临着新的挑战。IIDG侧附近的保护性能受到低压穿越（LVRT）和IIDG负序电流抑制控制特性的不利影响。这种保护的操作特性与配电网中使用的传统保护方案非常不同。传统的过电流保护方案不能满足选择性和灵敏度的要求。本文分析了IIDG对配电网保护方案的影响。根据正序电压极化阻抗标准，提出了一种基于正序电压故障分量的极化阻抗准则，该准则可以自适应地跟踪故障电阻的变化，以满足电网运行的要求。仿真结果表明：（a）所提出的准则不受IIDG暂态特性的不利影响，并且（b）它可以适应性地跟随故障电阻的变化，适用于短分布线路中的应用。使用专门的片上系统技术，已经开发了一种新型距离保护设备，并在工业现场进行了测试。新的距离保护装置可以满足IIDG配电网的要求。建议满足电网运行的要求。仿真结果表明：（a）所提出的准则不受IIDG暂态特性的不利影响，并且（b）它可以适应性地跟随故障电阻的变化，适用于短分布线路中的应用。使用专门的片上系统技术，已经开发了一种新型距离保护设备，并在工业现场进行了测试。新的距离保护装置可以满足IIDG配电网的要求。建议满足电网运行的要求。仿真结果表明：（a）所提出的准则不受IIDG暂态特性的不利影响，并且（b）它可以适应性地跟随故障电阻的变化，适用于短分布线路中的应用。使用专门的片上系统技术，已经开发了一种新型距离保护设备，并在工业现场进行了测试。新的距离保护装置可以满足IIDG配电网的要求。（b）它可以适应性地跟随故障电阻的变化，这适用于短配电线路中的应用。使用专门的片上系统技术，已经开发了一种新型距离保护设备，并在工业现场进行了测试。新的距离保护装置可以满足IIDG配电网的要求。（b）它可以适应性地跟随故障电阻的变化，这适用于短配电线路中的应用。使用专门的片上系统技术，已经开发了一种新型距离保护设备，并在工业现场进行了测试。新的距离保护装置可以满足IIDG配电网的要求。