Research On Distributed Capacitance Characteristics Of Non-contact Voltage Sensor Based On Electric Field Induction

The non-contact voltage sensor based on the principle of electric field induction has the advantages of simple structure,convenient measurement,wide linear range,stable transient response and fast response speed.It has on-line monitoring of high-voltage line faults,lightning current and partial discharge signal detection.Certain application value.In this paper,two non-contact voltage signal measurement models based on the principle of electric field induction are proposed.The main factors of distributed capacitance and the influence on sensor performance are studied.In this paper,the basic theoretical model of non-contact voltage sensor is established.The calculation method of electric field distribution,the shape of sensor plate,structural parameters and environmental factors affect the distributed capacitance of the sensor are studied.The edge effect of the sensor is studied by Ansoft Maxwell.Simulation and accurate calculation of capacitance method The effects of electric field edge effect on the plate capacitance of five kinds of shape sensor measurement models are studied.The research shows that the circular metal plate has the least influence on the sensor plate capacitance;The two sensor models of the wafer structure sensor and the metal ring sensor are used to study the influence of the structural parameters of the non-contact voltage sensor on the distributed capacitance.The corresponding equivalent circuit and mathematical model are established to study the results.The output characteristics of the structure sensor are most affected by the capacitance of the plate on the sensor.The output characteristics of the metal ring sensor are affected by the mutual capacitance between the sensor rings.The height of the sensor plate,the proximity of the conductor,the climate,etc.Factor to single metal wafer sensor,circle The structure sensor and the metal ring type sensor measure the influence of each distributed capacitance in the model.The results show that the height of the sensor plate to ground is less than(equal to)2m,which has little effect on the capacitance of the plate.The conductor of the vertical direction is the capacitance of the sensor plate.The influence of the paper is larger than that of the horizontal direction.Finally,the paper verifies the correctness of the theoretical research by setting experiments,and the experimental results show that it is consistent with the theoretical analysis.The non-contact measurement voltage signal sensor proposed in the paper has wide measurement frequency range,fast response speed and good transient performance.It can be used for fault signal detection.The influence of the distributed capacitance of the sensor on the measurement signal is helpful to solve the fault signal.Interference problems during the measurement process.