Abstract: As a kind of signal which contains rich fault information and is easy to obtain, phase asymmetric signal is frequently used in distribution network fault location technology. However, The interference of load current in distribution network and the huge difference of signal characteristics of different fault types pose greatly challenges to the application of phase asymmetric signal location technology. In order to solve the above problems, this paper proposes a single-phase grounding fault sensing technology based on the combination of transient and steady-state phase asymmetric signals. After single-phase grounding fault occurs in distribution network, the fault component currents of fault path and non-fault path will be different in transient and steady processes, and the degree of difference will change in different grounding types. According to the above characteristics, in this method, the improved S transform and variance method are combined to increase the difference between the fault path and the non-fault path, the harmonic content is adopted as the criterion to identify the fault type adaptively, and the location method is selected to realize the fault location. Moreover, the data of physical test platform are adopted to simulate the positioning technology, and the reliability and practicability of this technology are verified. The sensing technology can simultaneously meet the positioning requirements of multiple single-phase grounding fault types in distribution network with ungrounded neutral point and grounded by arc suppression coil. At the same time, this technology can realize local judgment without relying on communication system, and has strong practicability.