Digital electronic fluorescent scanning voltage sensor

Abstract

The invention relates to a digital electronic fluorescent scanning voltage sensor based on a principle of an action of an electric field force (a voltage) on motion electrons and a digital image processing technology. An electron current beam which is subjected to heat emission by a cathode is focused and accelerated by a direct current voltage, passes through an electric field formed by a voltage to be measured in vacuum, and bombards a fluorescent powder layer for light emitting; and a fluorescent light is transmitted to a charge coupled device (CCD) / complementary metal-oxide-semiconductor transistor (CMOS) image sensor. Two polar plates which form the electric field are connected to the voltage to be measured; the electrons are bombarded to different positions on the fluorescent powder layer under the action of the electric field force between the polar plates on the electrons; the change of light emitting positions is in proportion to the size of the electric field force (the voltage); and a real-time digital voltage signal is obtained by adopting the CCD / CMOS image sensor to measure the change of positions of light emitting points. A measuring method is linear and applied to measurement of an alternating current voltage and the direct current voltage of a power system.

Description

technical field [0001] The invention relates to a digital electron fluorescence scanning voltage sensor, which is suitable for the measurement of AC and DC voltages of power systems based on the action principle of electric field force (voltage) on moving electrons and digital image processing technology. Background technique [0002] At present, there are four types of voltage transformers or sensors that can be used for high voltage measurement: electromagnetic type, capacitive type, analog photoelectric type and active electronic type. [0003] The outstanding problems of electromagnetic voltage transformer in the application of ultra-high voltage and ultra-high voltage power system are its high electrical insulation cost and low reliability. Taking into account the requirements of safety, reliability, accuracy, cost performance, etc., electromagnetic voltage transformers are not suitable for high voltage levels. [0004] Capacitive voltage transformers are based on the ...

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Problems solved by technology

Its advantage is to realize the optical isolation between high and low potentials, but the disadvantage is that the method of light intensity measurement is nonlinear, and is seriously affected by stress birefringence, the measurement range is small, and the reliability is poor

[0006] The active electronic type uses a capacitive voltage divider, a resistive voltage divider or an inductive voltage divider to obtain a small voltage signal. The disadvantage is that the electrical isolation between high and low potentials is not realized.

[0007] The common disadvantage of the above transformers is that only analog voltage signals can be obtained on the low-voltage side, and digital signals need to be obtained by means of analog-to-digital conversion circuits, which has become an obstacle to the full digitalization of substations.

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