High voltage direct current (HVDC) / High voltage alternating current (HVDC) transmission lines have been implemented in many countries, including Australia, Brazil, China and Sweden and the safety concerns as the result of the high electromagnetic-radiation underneath the HVDC/HVAC lines have garnered increased public attentions. With the large-scale implementations of HVDC/HVAC transmission lines, the environmental impacts due to electromagnetic waves have become a focus of public attention in the following technical parameters: electric field, ion current density, space charge density, radio interference, audible noise, etc. Here, we report on the model, design and testing of electric field sensors to measure the electric field at the ground level under the HV transmission lines for the smart grid. This study utilized different principles to establish electric field measurement system based on the wireless sensor networks. Afterwards, these sensors were successfully tested and utilized at the national high-voltage test base.
