The Research Of A Self-constructed Electric Field Voltage Sensor Based On The Theory Of Electric Field Coupling

Voltage measurement is critical to the safe,reliable and economic operation of the power system.Its accuracy directly affects the stable operation of the power system,which is of great significance for the development of the smart grid.With the continuous improvement of China's smart grid,the requirements of voltage measurement for power systems are constantly improving.Traditional voltage transformers cannot meet the measurement requirements of power systems due to their own defects.Based on the principle of electric field coupling voltage measurement and a self-constructed electric field structure,a self-constructed electric field type voltage sensor based on electric field coupling principle is proposed.It is expected to be applied to the measurement of 10 kV power system instead of the traditional voltage transformer.The research content of this paper mainly includes is as follows:(1)The linear relationship between the charged conductor and the surrounding electric field is introduced.On the basis of this,the voltage measurement method based on the theory of electric field coupling is analyzed.The self-constructed electric field structure of the sensor is proposed.Combined with the theory of electric field coupling,a self-constructed electric field voltage sensor based on the theory of electric field coupling is proposed.The transfer function of the sensor is deduced,which provides the theoretical basis for the design and optimization of the sensor.(2)The low-frequency electromagnetic field simulation software Ansoft Maxwell is used to the modeling and simulation of the self-constructed electric field voltage sensor.The linear relationship of the sensor is verified.The optimal parameters of the sensor are determined to ensure the performance of the sensor.The sensor is made for the following test.(3)The hardware circuit and software system of the sensor are made.In order to convert the double-ended signal from the sensor into a single-ended signal,an acquisition circuit is designed.The conllected signal of the sensor is processed and displayed through the voltage measurement system.Finally the voltage measurement system is finished.(4)The experimental platform of the sensor is built and the linearity of the sensor is tested.The experimental results show that the sensor designed in this paper has good linearity.After correcting the linearity of the voltage measurement system,the test of the voltage measurement performance is conducted.The results prove that the voltage measurement system designed in this paper can accurately and quickly measure and display the voltage under the voltage level of 3kV~10kV.