A current comparator calibration circuit automatic switching device

Abstract

The present invention discloses an automatic switching device for a current comparator calibration circuit, and relates to the technical field of mutual inductor detection. The current comparator primary circuit switching device includes a linear motion unit, and the linear motion unit is used to drive the switches on both sides of the primary winding of the current comparator to close or open, and control the access of different primary windings on the primary side of the current comparator; the current comparator secondary circuit switching device includes a plurality of magnetic latching relays connected in parallel, each of the magnetic latching relays is connected in series with a secondary terminal of the current comparator, and the secondary terminal is connected to the secondary winding, and the magnetic latching relay is used to control the access of different secondary windings on the secondary side of the current comparator. The present invention realizes the automatic switching of the current comparator calibration circuit without the need for secondary intervention by the operator, and can improve the efficiency and intelligence of the current comparator calibration work under the premise of ensuring the consistency of the line impedance and ensuring the accuracy.

Description

Technical Field

[0001] The invention belongs to the technical field of mutual inductor detection, in particular to an automatic switching device for a current comparator calibration circuit. Background Art

[0002] The calibration of the current comparator is a multi-ratio, multi-line, and strongly coupled procedure. The calibration steps of the current comparator are complicated. The transformer standard transmission equipment needs to calibrate the current comparator gear by gear. Each ratio is wired separately, and each line is carried out independently. The operator needs to perform a large number of wiring processes and solve the data anomalies caused by the wiring process. Therefore, it is the technical key to the current current comparator calibration line switching operation to ensure the calibration efficiency and prevent the impedance influence and line interference during the calibration line connection from affecting the accuracy of the current comparator.

[0003] The inventors found that the above-mentioned manual operation of the switching process by operators in the prior art is not conducive to improving the calibration efficiency and has a low degree of automation. In order to meet the requirements of standardized operation management, improve the efficiency and intelligence of current comparator calibration, implement the automatic switching design of current comparator calibration lines, and realize the automatic switching design of multi-ratio multi-line. Summary of the invention

[0004] The purpose of the present invention is to provide an automatic switching device for a current comparator calibration circuit, which realizes automatic switching of the current comparator calibration circuit without the need for secondary intervention by an operator. It can improve the efficiency and intelligence of the current comparator calibration work while ensuring the consistency of the circuit impedance and the accuracy, and solve the problems in the prior art.

[0005] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0006] The present invention is an automatic switching device for a current comparator calibration circuit, comprising a primary circuit switching device for a current comparator and a secondary circuit switching device for a current comparator, wherein:

[0007] The current comparator primary circuit switching device includes a linear motion unit, which is used to drive the switches on both sides of the primary winding of the current comparator to close or open, and control the access of different primary windings on the primary side of the current comparator;

[0008] The current comparator secondary circuit switching device includes a plurality of magnetic latching relays connected in parallel, each of the magnetic latching relays is connected in series with a secondary terminal of the current comparator, the secondary terminal is connected to the secondary winding, and the magnetic latching relay is used to control the access of different secondary windings on the secondary side of the current comparator.

[0009] As an optional technical solution, the current comparator primary circuit switching device includes a horizontal holding platform, on which an opening and closing control component is arranged, the opening and closing control component includes a current comparator primary circuit common copper bus arranged on the horizontal holding platform, the top of the horizontal holding platform is connected to a linear motion unit through a frame bracket, the output end of the linear motion unit is connected to the current comparator primary circuit terminal copper bus, and the current comparator primary circuit terminal copper bus is arranged corresponding to the position of the current comparator primary circuit common copper bus.

[0010] As an optional technical solution, the linear motion unit is arranged on the top of the frame bracket, and a buffer gasket is arranged between the linear motion unit and the copper bar of the primary circuit terminal of the current comparator.

[0011] As an optional technical solution, a plurality of groups of opening and closing control components are provided on the horizontal holding platform.

[0012] As an optional technical solution, the secondary circuit switching device of the current comparator includes a cage-type fixing frame, which is arranged on the panel of the current comparator. A plurality of secondary terminals are also arranged on the panel of the current comparator. A combination circuit PCB is installed on the top of the cage-type fixing frame, and a plurality of magnetic latching relays are arranged on the combination circuit PCB.

[0013] As an optional technical solution, a control interface is further provided on the combined circuit PCB, and the internal wiring terminal of the control interface is connected to the control port of the magnetic latching relay.

[0014] As an optional technical solution, the bottom and side surfaces of the cage-type fixing frame are both hollowed out, a plurality of transverse support screws are evenly arranged on the bottom surface of the cage-type fixing frame along the length direction, and a plurality of longitudinal support screws are evenly arranged on the side surfaces of the cage-type fixing frame along the height direction.

[0015] As an optional technical solution, it also includes a CPU control unit, which includes a shielding shell, a CPU main control board and a control relay are arranged inside the shielding shell, and the control relay is connected to the CPU main control board through a control cable.

[0016] As an optional technical solution, the control relay of the CPU control unit is connected to the external terminal of the control interface of the secondary circuit switching device of the current comparator; the CPU main control board of the CPU control unit is also connected to the linear motion unit.

[0017] As an optional technical solution, the combined circuit PCB is processed by using an immersion gold process.

[0018] The present invention has the following beneficial effects:

[0019] 1. The present invention provides an automatic switching device for current comparator calibration circuit, which realizes the automatic switching of current comparator calibration circuit, wherein the primary side switching device adopts a linear motion unit to drive the terminal copper bar to move up and down, controls the opening and closing contact with the common copper bar, and realizes the automatic switching of the primary side circuit of the current comparator; the secondary side switching device adopts a cage frame structure, and a magnetic latching relay is arranged on the combined circuit PCB at the top of the cage frame structure, and the automatic switching of the secondary side circuit is controlled by the on and off of the magnetic latching relay. The present invention does not require secondary intervention of the operator, and can improve the efficiency and intelligence of the current comparator calibration work under the premise of ensuring the consistency of the line impedance and ensuring the accuracy.

[0020] 2. The cage-type fixing frame, transverse support screws and longitudinal support screws of the secondary circuit switching device of the present invention are all made of metal, which can shield the electromagnetic interference of the external environment and ensure that the test signal is not distorted when it is a small signal; the shielding shell of the CPU control unit adopts a metal structure, which can achieve electromagnetic shielding and prevent external electromagnetic interference from affecting the action of the control relay in the shielding shell.

[0021] 3. The combined circuit PCB of the present invention is processed by immersion gold process. Compared with the tin spraying process, the immersion gold process has smaller impedance, stronger anti-interference ability, and easier to control stress.

[0022] 4. The magnetic latching relays of the present invention all adopt high current low impedance magnetic latching relays, and the internal impedance is less than , and adopt multiple groups in parallel to ensure that the overall impedance control range of the combined circuit PCB is less than 60 .

[0023] 5. The buffer gasket of the primary circuit switching device of the present invention can reduce the metal friction during the crimping process of the linear motor and provide a buffer force between the motor and the copper busbar; the primary circuit terminal copper busbar is connected to the buffer gasket, and the terminal copper busbar can pass a large current without heating, thereby avoiding affecting the test error and ensuring the test accuracy.

[0024] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0026] Figure 1 It is a schematic structural diagram of the primary circuit switching device of the current comparator of the present invention.

[0027] Figure 2 It is a schematic structural diagram of the secondary circuit switching device of the current comparator of the present invention.

[0028] Figure 3 It is a schematic diagram of the structure of the CPU control unit of the present invention.

[0029] Figure 4 Schematic diagram of the primary circuit of the current comparator of the present invention.

[0030] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0031] 1. Current comparator primary circuit switching device; 2. Frame bracket; 3. Motor fixing plate; 4. Linear motor; 5. Buffer gasket; 6. Current comparator primary circuit terminal copper bar; 7. Current comparator primary circuit common copper bar; 8. Level holding table; 9. Control port; 10. Opening and closing control component; 11. Current comparator secondary circuit switching device; 12. Magnetic holding relay; 13. Control interface; 14. Combined circuit PCB; 15. Cage fixing frame; 16. Longitudinal support screw; 17. Horizontal support screw; 18. Current comparator panel; 19. Secondary terminal; 20. CPU control unit; 21. Shielding shell; 22. Control relay; 23. CPU main control board; 24. Power supply interface; 25. Control cable. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Embodiment 1:

[0034] As mentioned above, the current comparator calibration steps in the prior art are complicated, the transformer standard transmission equipment needs to calibrate the current comparator gear by gear, each ratio is wired separately, and each line is carried out independently. The operator needs to perform a large number of wiring processes, and needs to solve the data anomalies caused by the wiring process. It not only improves the calibration efficiency, but also prevents the impedance influence and line interference during the calibration line connection process from affecting the accuracy of the current comparator. It is the technical key to the automatic switching of the current comparator calibration line.

[0035] The current comparator in the prior art has a wire package inside, and multiple groups of wire ends are led out on the surface of the upper panel, that is, multiple groups of coil lead-out ends are collectively led to the column head of the top panel of the transformer, and these column heads include secondary terminal 19 head (that is, secondary terminal 19 in this embodiment), grounding column head, etc. Since the self-calibration process requires the use of different current ratios, different current ratios are formed by connecting multiple groups of column heads in parallel or in series, resulting in complicated wiring steps and a long time consumption.

[0036] In view of the above technical problems, a specific embodiment of the present invention provides an automatic switching device for current comparator calibration circuit, which can automatically switch the wiring mode, change the current ratio, and realize the selective connection or disconnection of multiple windings. In general, the technical solution of this embodiment connects all windings in parallel, and uses a certain winding by closing the switch, and disconnects the switches of other windings when they are not in use.

[0037] Specifically, when controlling the access to the primary winding, the primary side of the current comparator switches the circuit through the linear motor 4 and the copper busbar; when controlling the access to the secondary winding, the secondary side switches the circuit through the magnetic holding relay 12 of the secondary switching device unit, and all winding circuit switching is completed by the CPU control unit 20.

[0038] See also Figure 1-2 As shown, the current comparator calibration circuit automatic switching device provided in this embodiment includes a current comparator primary circuit switching device 1 and a current comparator secondary circuit switching device 11, wherein:

[0039] The current comparator primary circuit switching device 1 includes a linear motion unit, which is used to drive the switches on both sides of the primary winding of the current comparator to close or open, and control the access of different primary windings on the primary side of the current comparator;

[0040] The current comparator secondary circuit switching device 11 includes a plurality of magnetic latching relays 12 connected in parallel, each of the magnetic latching relays 12 is connected in series with a secondary terminal 19 of the current comparator, the secondary terminal 19 is connected to the secondary winding, and the magnetic latching relay 12 is used to control the access of different secondary windings on the secondary side of the current comparator.

[0041] The CPU control unit 20 controls the actions of the current comparator primary circuit switching device 1 and the current comparator secondary circuit switching device 11, thereby realizing the access of the primary side winding and the secondary side winding. It is very convenient to realize the change of the access of the primary side winding and the change of the access of the secondary side winding, and realize automatic line switching.

[0042] It can be understood that the CPU control unit 20 is electrically connected to the current comparator primary circuit switching device 1 and the current comparator secondary circuit switching device 11 respectively, thereby completing the control of the opening and closing actions.

[0043] like Figure 1 As shown, the current comparator primary circuit switching device 1 includes a horizontal holding platform 8, which provides a mounting carrier for the components arranged thereon. The horizontal holding platform 8 is provided with an opening and closing control component 10, which includes a current comparator primary circuit common copper bar 7 arranged on the horizontal holding platform 8, a frame bracket 2, a linear motion unit, and a current comparator primary circuit terminal copper bar 6.

[0044] The frame support 2 is a frame structure, including a top support plate and a support frame arranged at the bottom of the top support plate, the support frame is connected to the upper surface of the horizontal holding platform 8, and a linear motion unit is installed on the top support plate. In this embodiment, the linear motion unit is a linear motor 4, which is installed on the lower surface of the top support plate through a motor fixing plate 3 and is arranged toward the horizontal holding platform 8. The setting of the support frame provides a motion space for the motion of the linear motor 4.

[0045] The output end of the linear motor 4 is connected to the copper bar 6 of the primary circuit terminal of the current comparator, driving the copper bar 6 of the primary circuit terminal of the current comparator to move up and down. The copper bar 6 of the primary circuit terminal of the current comparator is arranged correspondingly to the position of the common copper bar 7 of the primary circuit of the current comparator. When the copper bar 6 of the primary circuit terminal of the current comparator moves downward to contact the common copper bar 7 of the primary circuit of the current comparator, it is equivalent to the switch being closed, and the primary side winding connected to the common copper bar 7 of the primary circuit of the current comparator is connected; when the copper bar 6 of the primary circuit terminal of the current comparator moves upward to be separated from the common copper bar 7 of the primary circuit of the current comparator, it is equivalent to the switch being opened, and the primary side winding connected to the common copper bar 7 of the primary circuit of the current comparator is disconnected.

[0046] In order to better understand the above process, Figure 4 As shown, it is a schematic diagram of the primary circuit of the current comparator of this embodiment. The circuit includes a standard current transformer and a current transformer under test. A switch is set on both sides of the standard current transformer. When the switch is turned off, there is no current in the circuit, indicating that it is not connected; when the switch is closed, it means that there is current in the circuit and it is connected. The standard current transformer needs to select different primary windings, so the left and right switches are used to realize the selection function. The functions of the copper busbar 6 of the primary circuit terminal of the current comparator and the common copper busbar 7 of the primary circuit of the current comparator in the above description are equivalent to the function of the switch here. When the switch is closed, the primary winding in the current circuit is connected; when the switch is turned off, the primary winding of the current circuit is not connected.

[0047] Similarly, the access control of the parallel primary windings can be performed by other switches. Therefore, the horizontal holding platform 8 is provided with multiple groups of switch control components 10, each group of switch control components is equivalent to a switch, which controls whether multiple primary windings are connected.

[0048] The primary side of the current comparator is composed of multiple windings connected in series and parallel, and the primary side windings with different transformation ratios are switched by switches.

[0049] In order to control the reaction force at the moment of contact, a buffer gasket 5 is further provided between the linear motor 4 and the copper busbar 6 of the primary circuit terminal of the current comparator.

[0050] More specifically:

[0051] The frame support 2 of the primary circuit switching device is connected to the horizontal holding platform 8 and the motor fixing plate 3 through a nut. The motor fixing plate 3 can position the linear motor 4 so that the linear motor 4 can be fixed in relative position when the copper bar 6 of the primary circuit terminal of the current comparator is crimped with the common copper bar 7 of the primary circuit of the current comparator; the linear motor 4 is installed under the motor fixing plate 3, and the bottom is connected to the buffer gasket 5. The linear motor 4 can provide a crimping stroke to realize the opening and closing between the copper bars; the buffer gasket 5 can reduce the metal friction during the crimping process of the linear motor 4 and provide a buffer force between the motor and the copper bar; the copper bar of the primary circuit terminal is connected to the buffer gasket 5, and the copper bar can pass a large current without heating and affecting the test error. The common copper bar of the primary circuit is installed on the horizontal holding platform 8 and under the copper bar of the primary circuit terminal, and is used for switching between different circuits of the current comparator. The horizontal holding platform 8 is an insulating structure, which can fix the primary switching device of the current comparator, adjust the height and keep it stable. The control port 9 is connected to the aviation plug of the CPU control unit 20 to control the lifting and lowering of the linear motor 4.

[0052] like Figure 2 As shown, the current comparator secondary circuit switching device 11 is a cage-type rectangular parallelepiped as a whole, and the secondary circuit switching device includes a magnetic latching relay 12, a control interface 13, a combined circuit PCB 14, a cage fixing frame 15, a longitudinal support screw 16 and a transverse support screw 17.

[0053] The cage-type fixing frame 15 is integrally arranged on the panel of the current comparator, and a plurality of secondary terminals 19 are also arranged on the panel of the current comparator. A combination circuit PCB 14 is installed on the top of the cage-type fixing frame 15, and a plurality of magnetic latching relays 12 are arranged on the combination circuit PCB 14. The magnetic latching relays 12 are connected to the secondary terminals 19 on the current comparator panel 18.

[0054] Among them, the cage fixing frame 15 plays the role of overall support and is fixed on the panel of the current comparator. The bottom and side surfaces of the cage fixing frame 15 are hollowed out. The bottom surface of the cage fixing frame 15 is evenly provided with a plurality of transverse support screws 17 along the length direction, and the side surfaces of the cage fixing frame 15 are evenly provided with a plurality of longitudinal support screws 16 along the height direction. The transverse support screws 17 and the longitudinal support screws 16 jointly reinforce the cage fixing frame 15, the longitudinal support screws 16 are located on the four side surfaces, and the transverse support screws 17 are located on the lower bottom surface.

[0055] The cage fixing frame 15 is fixed between the current comparator panel 18 and the combined circuit PCB 14 through the longitudinal support screws 16 and the transverse support screws 17. Since the cage fixing frame 15 and the support screws are both made of metal, they can shield the electromagnetic interference of the external environment and ensure that the test signal is not distorted when it is a small signal.

[0056] The combined circuit PCB 14 is installed on the upper plane of the cage fixing frame 15 and is processed by the immersion gold process. Compared with the tin spraying process, the immersion gold process has lower impedance, stronger anti-interference, and easier stress control. The combined circuit PCB 14 is provided with a plurality of mounting holes for the magnetic latching relay 12, which are used to fix the magnetic latching relay 12; the combined circuit PCB 14 is also provided with a control interface 13, the external wiring terminal of the control interface 13 is connected to the CPU control unit 20, and the transmission of the control instructions of the CPU control unit 20 is realized; the internal wiring terminal of the control interface 13 is connected to the control port 9 of the magnetic latching relay 12, and the switching of the magnetic latching relay 12 is controlled.

[0057] The magnetic latching relay 12 is installed on the combined circuit PCB 14, the control terminal is connected to the internal terminal of the control interface 13, the contact is connected to the secondary terminal 19 of the current comparator, and for the circuit with high impedance requirements, multiple groups of parallel connection are used to control the connection wire resistance of about The magnetic latching relay 12 adopts a large current low impedance magnetic latching relay 12, and the internal impedance is less than .

[0058] According to the general conductor resistance calculation formula:

[0059] (Formula 1)

[0060] In formula 1, is the resistance per unit area, in ; is the conductor length in mm; is the conductor width in mm; is the conductor thickness in ; is the conductor resistance value, in units of .

[0061] Copper at 25°C 0.49 .

[0062] In the combined loop PCB 14, the copper size is 5 mm in width and about 35 mm in thickness. , the length is 80mm. At 25℃, 0.49 According to formula 1, the impedance of the combined loop PCB14 is:

[0063]

[0064] The impedance of each group of magnetic latching relays 12 is less than 10 , and multiple groups are connected in parallel, so the overall impedance control range of the combined loop PCB14103 is less than 60 .

[0065] like Figure 3 As shown, the CPU control unit 20 includes a shielding shell 21, a control relay 22, a CPU main control board 23, a power supply interface 24 and a control cable 25.

[0066] Among them, the shielding shell 21 is a shell structure, and a CPU main control board 23 and a control relay 22 are arranged inside. The shielding shell 21 adopts a metal structure, which can achieve electromagnetic shielding effect and prevent external electromagnetic interference from controlling the operation of the relay 22. The control relay 22 is placed in the shielding shell 21, and is mainly used to control the opening and closing of the magnetic holding relay 12. After the control is completed, the power is cut off, and it can have input and output electrical isolation characteristics and strong anti-interference ability. The CPU main control board 23 is connected to the control relay 22 through a control cable 25, and the control cable 25 is used for signal transmission between the CPU main control board 23 and the control relay 22. The CPU main control board 23 is the control part of this embodiment, and the switching function of each calibration circuit of the current comparator is realized through instructions.

[0067] More specifically, the control relay 22 of the CPU control unit 20 is connected to the external terminal of the control interface 13 of the current comparator secondary circuit switching device 11, and the CPU main control board 23 of the CPU control unit 20 is also connected to the linear motor 4 to realize the transmission of the control instructions of the CPU main control board 23. The shielding shell 21 is also provided with a power supply interface 24 for connecting an external power supply to supply power to the CPU main control board 23.

[0068] Working principle:

[0069] When the present embodiment is in use, the CPU main control board 23 of the CPU control unit 20 transmits the control command to the control relay 22 through the control cable 25, and the control relay 22 controls the opening and closing of the magnetic latching relay 12 of the secondary circuit switching device 11 of the current comparator, thereby realizing the access control of the secondary winding corresponding to the secondary terminal 19 connected to the magnetic latching relay 12;

[0070] The CPU main control board 23 of the CPU control unit 20 transmits the control instruction to the linear motor 4 of the current comparator primary circuit switching device 1 to control the running direction and stroke of the linear motor 4. When the linear motor 4 drives the current comparator primary circuit terminal copper bus 6 to move downward to contact with the current comparator primary circuit common copper bus 7, at this time, the primary side winding connected to the current comparator primary circuit common copper bus 7 is connected; when the current comparator primary circuit terminal copper bus 6 moves upward to separate from the current comparator primary circuit common copper bus 7, at this time, the primary side winding connected to the current comparator primary circuit common copper bus 7 is disconnected.

[0071] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0072] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific implementation methods described. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A current comparator calibration circuit automatic switching device, characterized in that: It includes a current comparator primary circuit switching device and a current comparator secondary circuit switching device, wherein: The current comparator primary circuit switching device includes a linear motion unit, which is used to drive the switches on both sides of the primary winding of the current comparator to close or open, and control the access of different primary windings on the primary side of the current comparator; The current comparator secondary circuit switching device comprises a plurality of magnetic latching relays connected in parallel, each of the magnetic latching relays is connected in series with a secondary terminal of the current comparator, the secondary terminal is connected with the secondary winding, and the magnetic latching relay is used to control the access of different secondary windings on the secondary side of the current comparator; The current comparator primary circuit switching device comprises a horizontal holding platform, an opening and closing control component is arranged on the horizontal holding platform, the opening and closing control component comprises a current comparator primary circuit common copper bar arranged on the horizontal holding platform, a linear motion unit is connected to the top of the horizontal holding platform through a frame bracket, an output end of the linear motion unit is connected to a current comparator primary circuit terminal copper bar, and the current comparator primary circuit terminal copper bar is arranged correspondingly to the position of the current comparator primary circuit common copper bar; The opening and closing control components on the horizontal holding platform are provided with multiple groups; The primary side switching device uses a linear motion unit to drive the terminal copper bar to move up and down, control the opening and closing contact with the common copper bar, and realize the automatic switching of the primary side circuit of the current comparator; The current comparator secondary circuit switching device comprises a cage-type fixing frame, a combined circuit PCB is installed on the top of the cage-type fixing frame, and a plurality of magnetic latching relays are arranged on the combined circuit PCB; The combined circuit PCB is also provided with a control interface, and the internal wiring terminal of the control interface is connected to the control port of the magnetic latching relay; It also includes a CPU control unit, which includes a shielding shell, and a CPU main control board and a control relay are arranged inside the shielding shell; The control relay of the CPU control unit is connected to the external connection terminal of the control interface of the secondary circuit switching device of the current comparator.

2. The current comparator calibration circuit automatic switching device according to claim 1, characterized in that: The linear motion unit is arranged on the top of the frame support, and a buffer gasket is arranged between the linear motion unit and the copper bar of the primary circuit terminal of the current comparator.

3. The current comparator calibration circuit automatic switching device according to claim 1, characterized in that: The cage-type fixing frame is arranged on the panel of the current comparator, and a plurality of secondary connecting posts are also arranged on the panel of the current comparator.

4. The current comparator calibration circuit automatic switching device according to claim 3, characterized in that: The bottom and side surfaces of the cage-type fixing frame are both hollow-out designs; a plurality of transverse support screws are evenly arranged on the bottom surface of the cage-type fixing frame along the length direction; and a plurality of longitudinal support screws are evenly arranged on the side surfaces of the cage-type fixing frame along the height direction.

5. The current comparator calibration circuit automatic switching device according to claim 1, characterized in that: The control relay is connected to the CPU main control board via a control cable.

6. The current comparator calibration circuit automatic switching device according to claim 5, characterized in that: The CPU main control board of the CPU control unit is also connected to the linear motion unit.

7. The current comparator calibration circuit automatic switching device according to claim 3, characterized in that: The combined circuit PCB is processed by using the immersion gold process.

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