Detection Method And Safety Warning System Of Power Frequency Electric Field

In recent years, with the development of science and technology, there is a grow demand for the electrical energy. Security and stability of power supply is the main goal of intelligent power grid construction, which is important to ensure the normal production. The power grid maintenance needs live operation, which is accident prone. A comprehensive safety strategy of operation specification was proposed to reduce the accident rate. Apart from this, designing a technical method to guarantee construction safety is also meaningful. In order to cope with this problem, the power frequency electric field detection and warning system is designed in this thesis.The power frequency electric field distribution of high voltage power line is studied in this thesis by means of simulation and field testing. And the power frequency electric field detection and safety warning system is designed. The system includes algorithms and circuits. The content and conclusion are as follows.(1) The mathematical model of electric field distribution of high voltage power line in free space is established. Electric field distribution in complex environment is simulated by electromagnetic field simulation software. And the distortion caused by human body is also analyzed.(2) By analyzing the functional requirements of the system, the design scheme is presented. The main functional modules are electric field intensity detection, motion displacement measurement, and voltage level discrimination. The feasibility of the scheme is demonstrated.(3) The hardware circuit of the system is designed. The hardware consists of electric field signal detection circuit, SD card driver, power supply circuit, interactive interface circuit etc. The drivers for the system, which includes gyroscope, OLED, and detection circuit, are programmed. The motion displacement detection algorithm and voltage level discrimination algorithm introduced in this thesis are achieved. And a terminal based on raspberry pi for field detection is developed.(4) The measurement system is calibrated with HI-3604. And the accuracy of the system is analyzed by contrast experiments. The algorithms of displacement detection by integration and pedometer are compared with the consideration of gyroscope data error, and the result shows that pedometer is better. The simulation result demonstrates that the voltage level discrimination algorithm is accurate with field intensity error.