Instrument for measuring static electricity on line

Abstract

The invention discloses an instrument for measuring static electricity on line, belongs to the field of static electricity monitoring, and particularly relates to the instrument for measuring static electricity on line. A static electricity sensor consists of a sensing metal surface, a shielding metal surface and an insulation sheet; the sensing metal surface is fixed on one surface of the insulation sheet; the shielding metal surface is fixed on the other surface of the insulation sheet; and a bimorph piezoelectric vibrator is fixed on the shielding metal surface of the static electricity sensor. The instrument for measuring the static electricity on line has the characteristics of low driving voltage, low vibrating frequency and large vibrating amplitude, can pass the safe explosion-proof authentication, and can measure the static electricity on line and make an alarm in places where oil products and flammable and explosive gases are stored and transported, so that a present blank in the field is filled up; and enough sensing voltage and sensing current can be obtained on the sensing metal surface, so that a final measurement value has a relative high linearity.

Description

technical field [0001] The invention belongs to the field of static monitoring, in particular to an online static measuring instrument. Background technique [0002] Lightning strikes, friction between objects, alternating current induction, etc. will generate static electricity. Static electricity that is not introduced into the ground will produce a changing or static electric field. At present, the measurement methods for static electricity are divided into static measurement methods without mechanical movement and dynamic measurement methods with mechanical movement. No matter what the measurement method is, the electrostatic induction surface that is non-contact and maintains a sufficient safety distance is used as the collection point of the electrostatic induction charge. The electrostatic static measurement method is mainly used to measure the changing electric field. If the net charge on the electrostatic surface is constant, If the electric field is constant, the c...

AI Technical Summary

Problems solved by technology

[0002] Lightning strikes, friction between objects, alternating current induction, etc. will generate static electricity. Static electricity that is not introduced into the ground will produce a changing or static electric field. At present, the measurement methods for static electricity are divided into static measurement methods without mechanical movement and dynamic measurement methods with mechanical movement. No matter what the measurement method is, the electrostatic induction surface that is non-contact and maintains a sufficient safety distance is used as the collection point of the electrostatic induction charge. The electrostatic static measurement method is mainly used to measure the changing electric field. If the net charge on the electrostatic surface is constant, If the electric field is constant, the current from the sensing surface to the operational amplifier will be very small, even reaching the pA level current, and the final measurement result will be very unstable, because the air flow, air humidity and temperature, and the leakage current of the line will all have great influence on the measurement result. The current electrostatic static measurement method is mainly used to measure the changing electric field, and it is basically impossible to measure the static electric field

[0003] Electrostatic dynamic measurement methods, traditional methods include motor drive, solenoid drive, piezoelectric ceramic drive, tuning fork switch drive, etc. Both motor drive and solenoid drive require a large current, and the energy stored in the inductor is far greater than that of oil The intrinsically safe explosion-proof requirements of electrostatic detection products in storage and transportation places can meet the explosion-proof requirements by continuously filling the electrostatic sensor with inert gas, because the dynamic measurement electrostatic sensor cannot be made into a product with a closed shell, and an open space is needed to introduce Electric field lines to the sensing surface of the sensor, so inert gas needs to be continuously filled to meet the flameproof requirements, which greatly increases the cost

[0004] Piezoelectric ceramics drive requires high voltage, even up to 200V, but even with such a high voltage, the amplitude generated by piezoelectric ceramics is still too small to generate enough induced voltage and current on the sensing surface of the electrostatic sensor. 200V high voltage, even with a small current consumption, it is difficult to complete the intrinsically safe explosion-proof certification

In the prior art, the measurer needs to hold the electrostatic voltmeter, move the meter to the electrostatic surface from a distance, and complete the instantaneous electrostatic voltage measurement by instantaneous movement. The meter must be assisted by the measurer to move, and cannot complete online continuous measurement

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