Immunity research of wireless communication in switch cabinet monitoring and control

With the wide spread use of wireless data transmission technologies in offices and houses, and also due to the flaws of wired communication in LV wiring system in switchgear, the prospect of the application of existing wireless data transmission technologies to replace LV wiring in switchgear is attracting more and more researchers and manufacturers. The cost of using readily available wireless data transmission technologies to replace some or all of the low voltage wiring in switchgear is currently thought to be very low. The wireless communication doesn’t need transmitting media, so it can prevent the damage caused by conducted interference, and will not take up more space when the number of monitoring parameters increase. So it is easier to install and maintain. However, currently very little research has been carried out about its possible application in substation and MV switchgear, where electromagnetic interferences are rather complicated and of uncertain amplitude. There is still a scope to investigate the possibility of using such a low cost wireless data transmission technology in switchgear. One of the remaining challenges is to choose a proper wireless technology and prove its reliability in switchgears. This paper studies the feasibility of applying the Bluetooth and 802.11b wireless data transmission technologies for the purpose of Medium Voltage (MV) switchgear monitoring and control. In particular, a series of experiments are carried out to test the reliability of both Bluetooth and 802.11b devices for applications in switchgear under various interference conditions, and the immunity property of the two candidates is obtained preliminarily from experimental results. All results are presented and discussed in the paper.