RU192380U1 - High voltage voltage transducer - Google Patents

Abstract

The utility model relates to the field of electrical engineering and can be used for measuring AC voltage in medium voltage electric networks in electricity metering systems, measuring power quality indicators and relay protection. The utility model solves the problem of creating a voltage measuring transducer for medium voltage networks with high measurement accuracy, noise immunity, increased resistance to overvoltages, small weight and size characteristics, low material consumption, built-in design, the ability to measure without grounding, and the ability to implement digital interfaces. A high-voltage voltage transducer consists of a high-voltage electrode 1, at least two electrodes 2 and 4, a dielectric cage 3, a shielded conductor 5, a load resistance 6 and a processing module 7 placed in a housing made of a polymer dielectric material, with a capacitance C12 between the electrodes 2 and 4 exceed by an order of magnitude the capacitance C1 between the high-voltage electrode 1 and electrode 2 and the capacitance C2 between the high-voltage electrode 1 and electrode 4. With an increase in the capacitance C12 between the measuring elec 2 and 4 come conversion transfer function provides a signal which does not require additional integration, and there is no need to transform the grounding. 8 s.p. f-ly. 10 ill.

Description

Technical field

A useful model of a high-voltage voltage measuring transducer belongs to the field of electrical engineering and can be used for measuring alternating voltage in medium and high voltage electric networks in electric power metering systems, measuring power quality indicators and relay protection. The built-in design of the converter allows the use of medium and high voltage with simplified installation on overhead and cable power lines.

State of the art

Known electromagnetic measuring voltage transformers, consisting of primary and secondary windings on a magnetic core with cast solid insulation. The disadvantages of measuring voltage transformers include: excess power taken off, excess material consumption, the need for protection against overvoltage and overload, the presence of ferromagnetic resonance effect.

Known resistive and capacitive voltage dividers, consisting of the upper and lower arm of capacitors and / or resistances placed in a housing with cast insulation. The features of voltage dividers include: the complexity of manufacturing and assembling high-voltage resistors and capacitors, the obligatory grounding, the absence of complete galvanic isolation, the influence of stray capacitance on the measurement accuracy.

A known design of capacitive voltage measuring transducers, consisting of high voltage and measuring electrodes (RU2658150). The operation of voltage sensors is based on the effect of induction of an electric field in a polarized dielectric layer. Features of capacitive measuring transducers include: simple design, wide frequency measurement range, high linearity, the need for grounding, the presence of stray capacitance effects, the need for a differential signal integration circuit after the sensor.

The closest technical solution is the design of voltage measuring transducers (RU2012157570). The design of the prototype includes a set of overlapping coaxial electrodes placed in a housing made of a polymer dielectric material. The disadvantages of this prototype are the complexity of manufacturing the design, the lack of the ability to install on the conductor without rupture, the presence of stray capacitance effects, the need for a differential signal integration circuit after the sensor.

Utility Model Disclosure

The utility model solves the problem of creating a voltage measuring transducer for medium and high voltage networks with high measurement accuracy, noise immunity, increased resistance to overvoltages, small weight and size characteristics, low material consumption, built-in design, and the possibility of measuring without grounding.

The technical result is ensured by the use of the design of a high voltage measuring voltage transducer, consisting of a high voltage electrode 1, at least two electrodes 2 and 4, a dielectric frame 3, a shielded conductor 5, a load resistance 6 and a processing module 7, placed in a housing made of a polymer dielectric material, the capacitance C12 between the electrodes 2 and 4 exceeds by an order of magnitude the capacitance C1 between the high-voltage electrode 1 and electrode 2 and the capacitance C2 between the high-voltage electro th electrode 1 and 4.

With increasing capacitance C12 between the measuring electrodes 2 and 4, the transfer transfer function of the conversion provides a signal that does not require additional integration, and there is no need to ground the conversion.

The claimed device differs from the closest analogue:

Using the design of two or more measuring electrodes 2 of planar form.

Using a design of two or more measuring electrodes 2 of a coaxial shape with a gap for embedding on a wire.

By applying a design using an active analog signal processing module using an analog signal amplification circuit.

Application of the design using a digital signal processing module using digital signal processing based on an analog-to-digital converter and microcontroller.

Description of drawings

Next, the utility model will be described in detail with reference to the drawings using non-limiting illustrative embodiments of the invention, in which similar elements are denoted by the same reference numerals.

Figure 1 is a block diagram of a grounded voltage measuring transducer.

Figure 2 is a block diagram of a non-grounded voltage measuring transducer.

Figure 3.4 is a design of a voltage measuring transducer with non-open coaxial electrodes for installation on a cable or wire.

5, 6 - design of a voltage measuring transducer with a built-in current lead as a high voltage electrode.

7 is a design of a voltage measuring transducer with two coaxial measuring electrodes.

Fig, 9 - design of the measuring voltage Converter with open electrodes of a coaxial shape for embedding on a wire.

Figure 10 - design of a voltage measuring transducer with open electrodes of planar form for embedding on a wire.

Utility Model Implementation

The electrical circuit of the device is shown in FIG. 1-2, where C1 is the capacitance between electrodes 1 and 2, C2 is the capacitance between electrodes 1 and 4, C12 is the capacitance between electrodes 2 and 4, 6 is the load resistance, 7 is an analog or digital signal processing module. The design of the device is shown in FIG. 3-9 and includes a high voltage electrode 1, and a measuring electrode 2, a dielectric frame 3, a measuring and / or shielding electrode 4, a shielded wire 5, a load resistance 6 and an electronic processing module 7.

Coaxial measuring electrodes 2 and 4 are made of conductive tape and are placed on a frame made of a dielectric material with a high relative permittivity 3. With an increase in capacitance C12 between measuring electrodes 2 and 4, the voltage measurement is carried out by the differential method and allows measurement without grounding. As the frame material, a composite with a high dielectric constant and with a minimum temperature coefficient was used. The core of the wire 5 is connected to the ring electrode 2, the braid of the wire is connected to the shield 4. Parts 1, 2, 3, 4, 5 are filled in the body of a polymer dielectric material. The coaxial shape of the electrodes minimizes the influence of stray capacitance of third-party conductors on the transfer function of the converter.

The open type design is made with an additional gap of the high-voltage electrode 1, the measuring electrode 2, the dielectric frame 3, the shielding electrode 4, with a width sufficient to be inserted into the wire or cable of the required diameter. The high voltage electrode 1 is in electrical contact with an overhead line wire or cable.

The planar conversion design is a multilayer set of substrates with electroconductive circuits of electrodes deposited on them, which measure the electric field around the conductor.

Structurally, the conversion housing provides relative fixation of the high-voltage electrodes 1 and the dielectric frame 3 with the electrodes 2, 4. This ensures a constant value of the capacitance C1, C2, C12 and, accordingly, the stability of the transfer function.

The development of the utility model assumes the possibility of implementing device versions:

Using the design of coaxial-shaped electrodes, the electrode 4 acts as a shielding and overlaps the width of the electrode 2, and the high value of the mutual capacitance C12 is achieved by using thin-film insulation with high dielectric constant.

Using the design of planar-shaped electrodes, while electrodes 2 and 4 are located in the same plane as a parallel structure of the electrically conductive layer on a flat dielectric frame perpendicular to the axis of the current lead, and the high value of the mutual capacitance C12 is achieved by using thin-film insulation with high dielectric constant.

The use of a design with two or more measuring electrodes 2 of a planar shape placed on a single dielectric frame 3 connected in parallel and embedded in a common casing made of a polymer dielectric material.

Using a design with two or more coaxial measuring electrodes 2 placed on a single dielectric frame 3 with a common shielding electrode 4, connected to individual conductors 5 and load resistances 6, and embedded in a common casing made of polymer dielectric material, providing measurement channels with various dynamic and frequency ranges of measurement.

Application of the design using the built-in current lead as a high-voltage electrode 1.

Using a design with a gap for embedding on a wire in the design of a high-voltage electrode 8, electrodes 2 and 4, dielectric frame 3.

By using a design using an active analog signal processing module 7 using an analog signal amplification circuit based on precision operational amplifiers.

Using the design using a digital signal processing module 7 using digital signal processing based on an analog-to-digital converter and a microcontroller.

Claims (9)

1. A high voltage voltage measuring transducer, consisting of a high voltage electrode (1), at least two electrodes (2) and (4), a dielectric frame (3), a shielded conductor (5), a load resistance (6) and a processing module ( 7) placed in a housing made of a polymer dielectric material, while the capacitance (C12) between the electrodes (2) and (4) exceeds by an order of magnitude the capacitance (C1) between the high-voltage electrode (1) and the electrode (2) and the capacitance (C2) between high voltage electrode (1) and electrode (4). 2. The voltage measuring transducer according to claim 1, characterized by the design of coaxial-shaped electrodes, wherein the electrode (4) acts as a shield and overlaps the electrode (2) in width, and the high value of the mutual capacitance (C12) is achieved by using thin-film insulation with high dielectric constant. 3. The voltage measuring transducer according to claim 1, characterized in the design of planar-shaped electrodes, wherein the electrodes (2) and (4) are located in the same plane as a parallel structure of the conductive layer on a flat dielectric frame perpendicular to the axis of the current lead, and a high value of the mutual capacitance (C12) is achieved using thin film insulation with high dielectric constant. 4. The voltage measuring transducer according to claim 3, characterized by the presence of two or more measuring electrodes (2) of planar shape, placed on a single dielectric frame (3), connected in parallel and embedded in a common casing made of a polymer dielectric material. 5. The voltage measuring transducer according to claim 1, characterized by the presence of two or more coaxial measuring electrodes (2) placed on a single dielectric frame (3) with a common shielding electrode (4) connected to separate conductors (5) and load resistances ( 6) and filled in a common housing made of a polymer dielectric material, ensuring the operation of measurement channels with different dynamic and frequency ranges of measurement. 6. Measuring voltage converter according to paragraphs. 1-5, characterized by the use of a built-in current lead as a high-voltage electrode (1). 7. Measuring voltage converter according to paragraphs. 1-3, characterized by the presence of a gap for embedding the wire in the design of the high-voltage electrode (8), electrodes (2) and (4), the dielectric frame (3). 8. The measuring voltage Converter according to any one of paragraphs. 1-7, characterized by the use of an active analog signal processing module (7) using an analog signal amplification circuit based on precision operational amplifiers. 9. The measuring voltage Converter according to any one of paragraphs. 1-7, characterized by the use of a digital signal processing module (7) using digital signal processing based on an analog-to-digital converter and a microcontroller.

Images