CN211293041U

CN211293041U - High-precision large-range integrated current measurer

Info

Publication number: CN211293041U
Application number: CN201921954962.5U
Authority: CN
Inventors: 刘嘉文; 王皓
Original assignee: North China Electric Power University
Current assignee: North China Electric Power University
Priority date: 2019-11-13
Filing date: 2019-11-13
Publication date: 2020-08-18
Anticipated expiration: 2029-11-13

Abstract

The utility model provides an integral type current measurement ware on a high accuracy is on a large scale, its characterized in that includes that the semicircle ring shape fits with a contraceptive ring (1) and has semicircular groove's lower seat (2), and the one end of fitting with a contraceptive ring links to each other with lower seat is articulated, and the another side passes through the screw rod and links to each other, and the both ends of screw rod all add and are equipped with the lead sealing, fit with a contraceptive ring between (1) and the lower seat (2) and form one and supply the ring form through-hole (3) that the wire passes through of being surveyed the ring fit with a contraceptive ring and install iron core (4) on the semicircle ring (1), lower seat (2) in install iron core (5) under the semicircle ring, in lower seat (2), under iron core (5) be partly install hall circuit board (6), hall circuit. The utility model discloses simple structure, it is small, measurement accuracy is high, and stability is good.

Description

High-precision large-range integrated current measurer

Technical Field

The utility model relates to a current measurement components and parts, especially an electric current measurement ware that uses in the electrical switch cabinet, specifically speaking are high accuracy integral type electric current measurement ware on a large scale.

Background

At present, electric energy metering, fault monitoring and diagnosis are carried out, respective investment equipment completes respective application, data cannot be shared, and investment is wasted greatly. Numerous large-size terminal equipment on site are heavy and crowded, wiring criss-cross, and not only maintenance is inconvenient, but also brings hidden danger to the safety. The similar product, the design that the sampling iron core and the Rogowski coil are combined into a whole, the size is large, the structure is complex, the reliability is not high, the 4000A current measurement iron core is easy to saturate, the production consistency can not be ensured at the precision of 0.5% under the temperature of-40 ℃ to 85 ℃, the data analysis adopts sampling data remote transmission, a centralized traditional method is adopted, the communication is complex, the calculation is complex, and the power supply uses an external power supply, so that the wiring is complex and potential safety hazards are brought.

In a word, the current coil of the existing electric Hall type electric energy metering device has the problems of large volume, complex structure and inconvenient installation, and needs to be improved.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing an electric energy metering device's current coil have bulky, and the structure is complicated, installs inconvenient problem, designs one kind and is positive little, simple structure, high accuracy integral type current measuring device on a large scale that measurement accuracy is high.

The technical scheme of the utility model is that:

the utility model provides an integral type current measurement ware on a high accuracy is on a large scale, its characterized in that includes that the semicircle ring shape is fitted with a contraceptive ring 1 and has semicircular groove's lower seat 2, and the one end of fitting with a contraceptive ring links to each other with lower seat is articulated, and the another side passes through the screw rod and links to each other, and the both ends of screw rod are all installed the lead sealing additional, fit with a contraceptive ring 1 and form a ring form through-hole 3 that supplies to be surveyed the wire and pass through between lower seat 2 the fitting with a contraceptive ring 1 in install iron core 4 on the semicircle ring, lower seat 2 in install iron core 5 under the semicircle ring, in lower seat 2, iron core 5 partly install hall circuit board 6, hall circuit board 6.

The lower seat 2 comprises a lower shell 9, a lower iron core 5, a Hall circuit board 6 and a lower cover 10, wherein the lower iron core 5 and the Hall circuit board 6 are positioned in a space formed by connecting the lower shell 9 and the lower cover 10, a liquid crystal display screen 11 and an indicator lamp 12 are installed on the lower cover 10, and the liquid crystal display screen 11 and the indicator lamp 12 are both electrically connected with the Hall circuit board 6.

The lower shell 9 is provided with a lower shell integrated spring piece 19, and the lower iron core 5 is positioned in the lower shell 9 through the lower shell integrated spring piece 19.

The inner wall of the lower shell 9 is provided with a plurality of ribs 13 for supporting the Hall circuit board 6, and the bottom of the lower shell 9 is provided with a fixing bolt 14.

The lower shell 9 and the lower cover 10 are connected through matched buckle structures, a groove is formed in the upper edge of the lower shell, and an elastic buckle clamped into the groove is arranged on the lower cover.

The upper ring 1 is composed of an upper shell 15, an upper iron core 4 and an upper cover 16, a plurality of elastic clamping pieces 19 which enable the upper iron core to be positioned are connected to the inner wall of the upper shell 15, the upper surface of the upper iron core and the upper surface of the lower iron core are ensured to be on the same plane through the elastic clamping pieces 19, and the upper shell 15 and the upper cover 16 are connected through a buckle structure.

The upper cover 16 is provided with a current direction indication arrow 18.

The utility model has the advantages that:

the utility model discloses the Hall chip that uses the open loop principle carries out multi-functional, subminiature, integrated design, provides a brand-new theory and realizes the complete solution of this theory.

The utility model discloses use the Hall chip overall thinking of ring-opening principle, through subminiaturization iron core design and accurate air gap of opening, solve iron core saturation and precision problem, adopt good indeformable plastic raw materials of elasticity to global design, for the structural processing that this working of plastics production of cooperation (assurance demolding) goes on, the inner chamber design of large capacity provides the design space for multi-functional, subminiature intelligence board, compact structure, and is rationally distributed for characteristics such as batch production uniformity is good, the scene is easily installed and is maintained.

The utility model, through the concept of function integration, makes the whole small and exquisite, beautiful in appearance and convenient in installation; the inner cavity is large, so that the intelligent module is easy to realize function integration; the plastic part is not deformed at the temperature of minus 40 ℃ to 85 ℃, so that the air gap distance of the iron core is ensured not to change, and low-temperature drift is realized; the appropriate size of the section of the iron core ensures high-precision measurement under low current; the proper gap distance of the iron core air gap ensures unsaturated measurement under large current; the plastic material has high elasticity, does not deform after shrinkage, ensures that the iron core with large size error is installed in place and does not shake.

Drawings

Fig. 1 is a schematic view of the measurement principle of the present invention.

Fig. 2 is a schematic perspective view of the present invention.

Fig. 3 is a schematic diagram of the internal structure of the upper and lower shells of the present invention.

Fig. 4 is a rear view of the structure of fig. 2.

Fig. 5 is a schematic view of the installation structure of the upper iron core and the lower iron core of the present invention.

Fig. 6 is a schematic diagram of the internal structure of the present invention.

Fig. 7 is a schematic diagram of the size of the iron core of the present invention.

Fig. 8 is the current passing and actually measured current curve of the iron core of the embodiment of the present invention at different temperatures.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and examples.

As shown in fig. 1-6.

The utility model provides an integral type current measurement ware on a high accuracy is on a large scale, it includes that the semicircle ring shape fits with a contraceptive ring 1 and has semicircular groove's lower seat 2, as shown in fig. 2, the one end of fitting with a contraceptive ring links to each other with lower seat is articulated, and the another side passes through the screw rod and links to each other, and the both ends of screw rod all add and are equipped with the lead sealing, fit with a contraceptive ring 1 and form a ring form through-hole 3 that supplies to be surveyed the wire and pass through between lower seat 2 fit with a contraceptive ring 1 in install iron core 4 on the semicircle ring, lower seat 2 in install iron core 5 under the semicircle ring, in lower seat 2, lower iron core 5 be that the portion installs hall circuit board 6, hall. During specific implementation, lower seat 2 constitute by inferior valve 9, lower iron core 5, hall circuit board 6 and lower cover 10, inferior valve and lower cover are the injection molding, lower iron core 5, hall circuit board 6 location are installed liquid crystal display 11 and pilot lamp 12 on lower cover 10 in the space that inferior valve 9 and lower cover 10 linked together and constitute, liquid crystal display 11 and pilot lamp 12 all with hall circuit board 6 electrical connection. The lower shell 9 is integrally molded with a lower shell connector spring 19 (as shown in fig. 3), and the lower iron core 5 is pressed and positioned in the lower shell 9 through the lower shell connector spring 19. A plurality of ribs 13 (shown in fig. 6) for supporting the hall circuit board 6 are arranged on the periphery of the inner wall of the lower shell 9, and a fixing bolt 14 (shown in fig. 4) for fixing the hall circuit board 6 is arranged at the bottom of the lower shell 9. Inferior valve 9 and lower cover 10 be connected through the buckle structure that matches, be equipped with the recess along being equipped with the inferior valve, be equipped with the card on the lower cover and go into elastic buckle in the recess, the buckle structure of this embodiment adopts the same joint structure with current plastics joint spare, so no longer describe in detail.

During specific implementation, the upper ring 1 is composed of an upper shell 15, an upper iron core 4 and an upper cover 16, a plurality of elastic clamping pieces 17 (fig. 3) for positioning the upper iron core are connected to the inner wall of the upper shell 15, the upper surface of the upper iron core and the upper surface of the lower iron core are ensured to be on the same plane through the elastic clamping pieces 17, and the upper shell 15 and the upper cover 16 are connected through a buckle structure. The upper cover 16 is provided with a current direction indication arrow 18 (fig. 1 and 4).

The details are as follows:

this plastic construction not only needs the miniaturization of structure, the iron core is unsaturated, function integration, field installation simplification, batch production uniformity, measurement accuracy height, needs plastics non-deformable under the high low temperature moreover, easily encapsulating operation, outside line and box body firm in connection.

In order to meet the requirements, the following method is adopted in the concrete implementation:

1. the method uses a Hall chip based on an open-loop principle to measure current and a Hall chip based on a closed-loop principle to measure voltage as a general design concept. FIG. 1 is a schematic diagram of an open-loop circuit using a Hall chip with an open-close iron core with an air gap. The reason for using an open-loop hall current sensor is as follows:

the open-loop Hall current sensor has simple principle, small incision and small size, but the measured current can be very large, so the open type iron core structure required by the site is well processed, and the open loop is more flexible and can more easily meet the requirement of installation under the condition of having the requirement on the installation space;

the Hall current sensor based on the open-loop principle has larger impact current resistance, particularly under the condition of particularly high peak value, the sensor is not influenced, ten times or even twenty times of impact current cannot damage the sensor, and the magnetizing phenomenon is not easy to generate;

the open loop has low power consumption and is nearly constant.

Therefore, a current Hall chip using the open-loop principle has the following characteristics: the device not only meets the measurement requirements of an alternating current system and a direct current system, but also meets the design requirements of miniaturization, and has strong anti-saturation capacity and good reliability.

2. A special groove for installing a Hall chip;

in order to meet the requirement of terminal miniaturization, a groove special for installing a Hall chip and a supporting step body are designed in the figure 6, the groove ensures that the Hall chip is arranged on the upper surface of the lower iron core, and the pin of the Hall chip is completely insulated from the iron core.

3. Using small open-close iron cores with air gaps, resisting saturation of magnetic core

The open loop principle is used for measuring the current, so that the iron core is small, an enameled wire is not wound on the iron core, and a circuit is very simple, as shown in figure 1. The size of the iron core with the air gap determines the size of the saturation current, and the size of the air gap is designed to be unsaturated under the condition that a large current of 4000A is introduced.

4. The iron core is installed simply and reliably;

because iron core production size error is difficult to control, the installation of iron core plays the key role to the accurate measurement of electric current, takes the integration installation to play the board and solves this difficult problem: the mounting elastic plate has certain elasticity and is not easy to break; a fan-shaped design is adopted to wrap the iron core; the elastic plate is provided with a lead-in inclined plane to ensure smooth sliding into the box when the iron core is installed.

5. The integrated structure design ensures that the relative position of the iron core is not changed

The most difficult problem of solving of working of plastics is deformation under various complex environment, the utility model discloses a following scheme effectively solves the deformation problem

Firstly, upper and lower box adopts buckle structure to link to each other, guarantees about lid and the automatic screens locking of upper and lower casing, and the overhead kick guarantees that there is certain strength to guarantee that the screens does not drop, ensures the position unanimity, need not the fixed upper and lower box of construction bolt.

And the upper box cover and the lower box cover are clamped in the corresponding slot positions of the male and female, so that the upper box cover and the lower box cover are ensured to be positioned correctly.

6. High precision, low temperature float, anti-saturation design

In practical application, the metering is carried out in an interval of 0-600A, and the relay protection is carried out in an interval of 600A-4000A. Because anti saturation requires that the iron core air gap opening is big, in order to guarantee that the error is little when the undercurrent like this, to working of plastics deflection and iron core installation incision relative position very high requirement.

Firstly, carry out optimal design to the structure, guarantee open-close type iron core air gap interval uniformity. In order to achieve the aim, the structure adopts the following treatment that the plastic enables the upper and lower plastic joint surfaces not to deform through a certain thickness and a reinforcing structure;

secondly, the plastic material is specially selected, so that the requirements of high and low temperature and difficult deformation and aging are met. The raw material of makrolon9415 plastic is used, and the heat resistance, the strength and the rigidity are improved. The creep resistance, the dimensional stability, the wear resistance and other properties are improved, and the maximum allowable use temperature is higher.

Thirdly, a 125 ℃ high-temperature injection molding process is used, and the plastic part is easy to produce due to reasonable arrangement and shape of the structural reinforcing ribs. The reinforcing ribs and the deformation-preventing air gap holes are reasonably distributed, and in order to prevent shrinkage during cooling in high-temperature injection molding, the air gap holes are specially added to prevent cooling deformation.

7. A harness slot;

the wire harness groove ensures that the external wire harness cannot fall off from the box after the external wire harness is subjected to external tension; simultaneously for guaranteeing the integrated design, pencil or antenna lug weld on the pcb, the position of pencil trench is unanimous with the position cooperation of pcb.

8. The large inner cavity and the pcb are arranged;

realize big inner chamber in limited space for the pcb face is big enough, makes to satisfy intelligent function. The function pcb board of buckle formula installation in the working of plastics, simple to operate, the inner chamber is by the maximum utilization. The liquid crystal screen of the liquid crystal display panel protrudes out of the upper cover plate and is directly arranged on the upper cover plate in a clamping manner, so that the liquid crystal display panel is ensured not to interfere with the upper cover pcb; and meanwhile, corresponding upper and lower box threading holes are arranged, so that the electrical connection is ensured.

9. Simple and reliable field installation and illegal disassembly prevention

The equipment is required to be prevented from being illegally disassembled after being installed, the lead seal is used, and the lead seal can be installed according to the field environment by using a conventional matched lead seal cap and lead seal bolt.

In fig. 4, 14 is a lower box bottom fixing nut. Different equipment is installed on site, and can be fixed on the 14 through external bolts, so that the device is simple and reliable.

10. The design of the multifunctional plastic mold enables one set of mold to adapt to different use occasions.

11. The design size of the plastic part is determined by the electrical data of the iron core experiment.

Fig. 7 shows that the iron core design size adapted to the structure is obtained from experimental data, and experiments show that only the iron core with the size can meet the measurement from 0.1A to 4000A power frequency, so that the plastic part design must be strictly performed according to the size of the iron core. Fig. 8 is a curve of the applied current and the measured current at different temperatures, and it is seen that the electrical characteristics exhibit the high-precision linear low-temperature drift effect in consideration of the iron core structure and the above various design concepts.

Combining the 11-point design, the structure with the size of fig. 1, the maximum inner aperture of 42mm, the outer body size of 118 mm in length, 66 mm in width and 27.5 mm in height is formed. The integrated plastic structure design of high-precision large-range current measurement is realized.

The utility model discloses the part that does not relate to all is the same with prior art or can adopt prior art to realize.

Claims

1. The utility model provides an integral type current measurement ware on a high accuracy is on a large scale, its characterized in that includes that the semicircle ring shape fits with a contraceptive ring (1) and has semicircular groove's lower seat (2), and the one end of fitting with a contraceptive ring links to each other with lower seat is articulated, and the another side passes through the screw rod and links to each other, and the both ends of screw rod all add and are equipped with the lead sealing, fit with a contraceptive ring between (1) and the lower seat (2) and form one and supply the ring form through-hole (3) that the wire passes through of being surveyed the ring fit with a contraceptive ring and install iron core (4) on the semicircle ring (1), lower seat (2) in install iron core (5) under the semicircle ring, in lower seat (2), under iron core (5) be partly install hall circuit board (6), hall circuit.

2. The high-precision large-range integrated current measurer according to claim 1, wherein the lower base (2) is composed of a lower shell (9), a lower iron core (5), a Hall circuit board (6) and a lower cover (10), the lower iron core (5) and the Hall circuit board (6) are positioned in a space formed by connecting the lower shell (9) and the lower cover (10), a liquid crystal display (11) and an indicator lamp (12) are mounted on the lower cover (10), and the liquid crystal display (11) and the indicator lamp (12) are both electrically connected with the Hall circuit board (6).

3. The high-precision large-range integrated current measurer according to claim 2, wherein a lower shell integrated spring (19) is arranged in the lower shell (9), and the lower iron core (5) is positioned in the lower shell (9) through the lower shell integrated spring (19).

4. A high-precision large-range integrated current measurer according to claim 2, wherein the inner wall of the lower shell (9) is provided with a plurality of ribs (13) for supporting the hall circuit board (6), and the bottom of the lower shell (9) is provided with a fixing bolt (14).

5. A high-precision large-range integrated current measurer according to claim 2, wherein the lower casing (9) and the lower cover (10) are connected through a matched buckle structure, a groove is arranged on the upper edge of the lower casing, and an elastic buckle clamped in the groove is arranged on the lower cover.

6. The high-precision large-range integrated current measurer according to claim 1, wherein the upper ring (1) is composed of an upper shell (15), an upper iron core (4) and an upper cover (16), a plurality of elastic clamping pieces (17) for positioning the upper iron core are connected to the inner wall of the upper shell (15), the upper surface of the upper iron core and the upper surface of the lower iron core are ensured to be on the same plane through the elastic clamping pieces (17), and the upper shell (15) and the upper cover (16) are connected through a buckling structure.

7. A high-precision large-range integrated current measurer as claimed in claim 6, wherein said upper cover (16) is provided with a current direction indication arrow (18).