Study On The Measurement Of The Charge Density Of Thundercloud

Under certain conditions, vapor in the air will condense into water droplets formed thundercloud when it cools. The charge structure of thundercloud generally has three polar structure features. The upper part of clouds is the main positive charge region, the lower part is the main negative charge region, at the bottom is a weaker positive charge region. When the thundercloud internal charge accumulation reaches a certain extent it will produce lightning. The measurement of the charge density of the thundercloud cloud helps people to know the relationship and regularity between category, location, propagation characteristics of lightning and charge structure of thundercloud. It is of great significance to the detection and early warning of lightning. At present, the research of thundercloud mainly focuses on the electric field; the measurement of the charge density of the thundercloud provides another viable method for the detection of the thundercloud.Because the existing measuring instruments can’t meet the requirements of the thundercloud charge density measurement, in this paper, a system for measuring the charge density of thundercloud is designed; it can be placed on top of the hill or rises to the clouds by sounding balloon to measure. In order to overcome the special situation that the charged gas in the thundercloud has no fixed form, in this paper, we design a kind of charge induction sensor with double tube structure. By the fan, the thundercloud charged gas is sucked into charge sensor, measuring the electrostatic potential of charged gas, and calculating the charge density of thundercloud. Hardware circuit design using modular design, improve the stability of the system and reduce interference. Design scheme of hardware circuit using STM32 as main controller. The hardware circuits including STM32 peripheral circuit, vibration capacitance sensor driver circuit, signal processing circuit and power supply circuit, etc. STM32 peripheral circuit mainly includes clock circuit, digital analog conversion circuit and SD card driver circuit. The signal processing circuit comprises a signal amplifying circuit, filter circuit of low frequency and phase sensitive detection circuit. SD card provides a large capacity data storage guarantee for the measurement system for outdoor measurement. The last part of the system software design of the module design ideas and main program flow. Using uVision4 Keil to realize the design of each module driver, the software design of the upper computer is completed by using QT, realize intelligent control of measuring system, and provide intuitive data detection, query and other functions.According to the experimental results, thundercloud charge density measurement system based on STM32 has reached the requirement of measurement. With fast data acquisition, high precision and system stability. Under the simplified circuit design, the circuit anti-interference ability is strong, can carry on the data measurement under the different environment.