Single-phase ground injection signal source in small current grounding system as a auxiliary equipment of fault location has been used a lot in the site. However, when the structure of the grid changes, there may be a situation that multiple injection signal sources in parallel operation causing influence of the correction of fault location. In this paper, a single-phase grounded injection signal sources coordination control strategy is analyzed, in which the master scheduling server communicate with many injection signal sources in real time to form a distributed control system. When the operation mode of the distribution network changes, the master scheduling server control one of the injection signal sources into operation, while blocking other injection signal sources to avoid single-phase ground injection source’s malfunction and frequent adjustment. According to the different locations of the injection signal source, the difference of the fault location method is deeply analyzed. The digital simulation analysis validates the effectiveness of the proposed method.