| Nowadays, the automation of substations is becoming an irreversible trend, which makes the communication in substations highly important. Traditionally, twisted pair line, cable and optical fiber play the leading roles in the monitoring and control system of substations. However, some of their drawbacks are inevitable. They are room-taking when a lot of points need to be monitored, they worsen devices'insulation structures, long transmission lines are potential paths for electromagnetic interferences (EMI) and it is difficult to repair or change their structures or functions. Compared with the wired connection above, wireless technology provides a more reliable, flexible and low-cost solution. While the larger the system is, the more it will benefit from these advantages. However, there is seldom study on the reliability of wireless technologies application in substations currently.This paper studies the possibility of Bluetooth application in substations considering transmission rate, reliability, cost, energy consumption, etc. Based on field survey and literature review, typical EMI in substations are simulated in laboratory, and their time-domain and frequency-domain waveforms are recorded and analyzed.This paper designs and builds a demonstrator based on Bluetooth for EMC tests. The point-to-point transmission performance of Bluetooth under EMI mentioned above is tested. The conclusion is that Bluetooth is reliable facing all those EMI except that the transmission rate decreases slightly but obviously in case of EMI with strong component around 2.4 GHz, such as those generated by SF6 and vacuum gap breakdowns. A HV switchgear monitoring and control system based on Bluetooth is built as an example application. Several suggestions for improvement and future work of the study are listed in this paper.In all, we believe that Bluetooth can work reliably in substations with proper protections. It has a bright prospect in application to substation systems.
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