Miniature electric field measuring apparatus

Abstract

The invention relates to a miniature electric field measuring apparatus, which comprises an electric field probe, a signal simulation conditioning circuit, a data acquisition and processing circuit adopting a mixed-signal processing chip, and a data storage and transmission circuit based on ARM. The inside of the electric field probe is provided with a moving plate and a driving device thereof and two groups of fixed plates; the two groups of fixed plates are directly etched on a printed circuit board; and the driving device of the moving plate is a common miniature direct current motor. The position of the moving plate of the electric field probe is detected by acquiring fluctuating signals generated in phase change of an electrode of the direct current motor. The outputs of the two groups of moving plates are taken as the input of the mixed-signal processing chip after being amplified by two paths of alternating current, the input is subjected to internal programmable gain amplification and then directly performs alternating current difference sampling, and the peak value and the polarity of the electric field are detected by software detection. An acquired electric field value is transmitted to an intelligent storage card for storage or to a terminal computer in a wired or wireless mode. The miniature electric field measuring apparatus has the advantages of simple structure, inhibition of temperature drift, strong electromagnetic interference resistance, and wide dynamic range and high precision in measurement.

Description

1. Technical field [0001] The invention relates to a miniature electric field measuring device, in particular to a miniature electric field measuring instrument for atmospheric electric field measurement. 2. Background technology [0002] Existing instruments for electrostatic field measurement mainly use rotary electric field meters (also known as field mills), which use the principle that metal conductors will generate induced charges on their surfaces in an electric field to measure electric field strength. Since the electrostatic field is a slowly changing quantity, in order to obtain a continuous electric field measurement value, it is necessary to use a dynamic method for measurement, that is, to expose and shield the conductor alternately in the electric field. The fixed induction conductor is called the fixed piece, and the moving conductor that alternately shields the fixed piece is called the moving piece, and the moving piece is grounded by friction with the groun...

AI Technical Summary

Problems solved by technology

The former increases the complexity of the mechanical design, while the latter must use a stepping motor to drive the moving piece, the control circuit and control program are complex and costly

At the same time, the speed of the stepping motor is slow, which will reduce the sensitivity of the electric field probe

[0004] In the prior art, a brush is used for grounding on the motor shaft. The brush will wear out after long-term use, and it is prone to poor contact, which will cause the measurement signal to jitter.

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