Study of Transient Earth Voltage Sensor with Additional Plate

Air insulated switchgear is one of the critical equipment in modern distribution systems. Being a key unit in high voltage (HV) electrical systems in various ranges of voltages, makes switchgears vulnerable to phenomenon known as partial discharge (PD). According to statistics for past decades PD caused almost 40% of all failures and shortages in electrical systems. PD is tending to progress by time, accelerating the aging rate of insulating materials causing reduced insulation parameters, leading to inevitable breakdown of insulation layers. Implementation of the Transient Earth Voltage (TEV) sensors are common methods of locating the PD signals. However, in some cases TEV sensors might lack sensitivity in comparison with other conventional methods. This paper will focus on providing information about (TEV) sensor assembly process, propose TEV sensor of alternative design that offer higher sensitivity and its frequency response analysis. This paper also will contribute the TEV sensor design for future research to provide comparative analysis.