Research on wireless synchronous measurement system for total ground electric field under HVDC transmission lines

Being affected by the corona discharge and the environmental climate, the total ground electric field strength under DC transmission lines often changes randomly within a certain range. It is very significant for research and evaluation of electromagnetic environment of the DC transmission lines to develop a convenient and effective synchronous measurement system for total ground electric field. So a ZigBee-based distributed wireless measurement system for the measurement of total ground electric field is designed. The node configuration and the networking process of the wireless measurement network are analyzed, and the method to synchronize node time based on synchronization broadcast messages and the data transmission protocol based on time division multiple access (TDMA) mechanism are emphatically analyzed. Thus the synchronized acquisition and reliable transmission of electric field data can be implemented by very low algorithm cost and energy cost. On-site measurement testing results show that the proposed electric field measurement system is convenient to operate and the measured data can accurately reflect the actual distribution of total ground electric field.