A system, method and device for amplifying a secondary output weak voltage of a voltage divider

Abstract

The present application discloses a system, method and device for amplifying a secondary weak voltage output of a voltage divider. The system includes an inverting amplification system and a boosting system, wherein the inverting amplification system includes an operational amplifier, a first resistor and a second resistor, and the boosting system includes a booster, wherein the first resistor is connected in series with the second resistor, and the second resistor is connected in parallel with the operational amplifier; the booster has several winding sections wound in the manner of an inductive voltage divider, and a feedback voltage is drawn at the last winding section of the several winding sections, and the feedback voltage is fed back to the in-phase input terminal of the operational amplifier.

Description

Technical Field

[0001] The present invention relates to the field of electrical measurement, and more specifically, to a system, method and device for amplifying a weak voltage outputted secondary from a voltage divider. Background Art

[0002] The voltage divider is a special instrument for high voltage measurement. Due to its advantages of accurate testing, good linearity, and stable performance, it is widely used, so the number of inspections is large every year. During the inspection, the secondary voltage of the voltage divider to be inspected has a high voltage output of more than 100V. When the electronic voltage divider standard is used to inspect the test product, due to its low secondary output signal voltage, generally within 15V, the signal needs to be amplified to the same as the secondary voltage output of the test product to measure the difference with the secondary high voltage of the test product. If the electronic voltage divider standard is used to connect the electronic circuit to directly output high voltage, when the core components of the circuit fail, the highest DC voltage of the circuit power supply will be directly output and added to the external load, which may cause damage to the back-end connection equipment. If the voltage is amplified by the electronic voltage divider standard secondary connection isolation transformer, due to the existence of the transformer output internal resistance, when the load is connected, it will cause a certain voltage drop, resulting in load error, which will affect the accuracy of the secondary output of the voltage divider standard.

[0003] In view of the technical problems in the above-mentioned prior art that the electronic circuit is directly connected to output high voltage using the standard electronic voltage divider, which may cause damage to the back-end connected equipment, and the voltage is amplified by the isolation transformer through the standard secondary connection of the electronic voltage divider, which will affect the accuracy of the standard secondary output of the voltage divider, no effective solution has been proposed yet. Summary of the invention

[0004] The present invention provides a system, method and device for amplifying a weak voltage outputted from a secondary voltage divider, so as to at least solve the technical problems existing in the prior art that the direct output of high voltage by using a standard electronic voltage divider to connect an electronic circuit may cause damage to the back-end connection equipment, and that the voltage amplification by connecting an isolation transformer through a standard secondary voltage divider may affect the accuracy of the standard secondary output of the voltage divider.

[0005] According to one aspect of the present invention, there is provided a system for amplifying a secondary weak voltage output of a voltage divider, comprising: an inverting amplifying system and a boosting system, wherein the inverting amplifying system comprises an operational amplifier, a first resistor and a second resistor, and the boosting system comprises a booster, wherein the first resistor is connected in series with the second resistor, and the second resistor is connected in parallel with the operational discharger; the booster has a plurality of winding sections wound in the manner of an inductive voltage divider, and a feedback voltage is drawn at the last winding section of the plurality of winding sections, and the feedback voltage is fed back to the non-inverting input terminal of the operational amplifier.

[0006] According to another aspect of the present invention, a method for amplifying a weak secondary output voltage of a voltage divider is provided, comprising: determining system parameters; and determining a booster voltage and a secondary feedback voltage based on the system parameters, wherein the secondary feedback voltage is a voltage for error compensation of the weak secondary output voltage of the voltage divider.

[0007] According to another aspect of the present invention, a device for amplifying a weak secondary output voltage of a voltage divider is provided, comprising: a parameter determination module for determining system parameters; and a voltage determination module for determining a booster voltage and a secondary feedback voltage based on the system parameters, wherein the secondary feedback voltage is a voltage for performing error compensation on the weak secondary output voltage of the voltage divider.

[0008] The beneficial effect of the present invention is that the secondary low-voltage signal of the voltage divider is safely and accurately amplified through the inverting amplifier part and the booster, meeting the need of using the differential measurement method to calibrate the voltage divider test product. This solves the technical problems existing in the prior art that the standard electronic voltage divider is used to directly output high voltage through the electronic circuit, which may cause damage to the back-end connection equipment, and the standard electronic voltage divider is used to connect the isolation transformer to amplify the voltage, which will affect the accuracy of the standard secondary output of the voltage divider. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The drawings described herein are used to provide a further understanding of the present disclosure and constitute a part of the present application. The illustrative embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute an improper limitation on the present disclosure. In the drawings:

[0010] Figure 1 A schematic diagram of a system for amplifying a voltage divider and outputting a weak voltage for a second time according to an embodiment of the present invention;

[0011] Figure 2 A schematic diagram of a method for amplifying a secondary weak voltage output by a voltage divider according to an embodiment of the present invention; and

[0012] Figure 3 It is a schematic diagram of a device for amplifying a voltage divider and outputting a weak voltage secondarily according to an embodiment of the present invention. DETAILED DESCRIPTION

[0013] Now, exemplary embodiments of the present invention are described with reference to the accompanying drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to disclose the present invention in detail and completely and to fully convey the scope of the present invention to those skilled in the art. The terms used in the exemplary embodiments shown in the accompanying drawings are not intended to limit the present invention. In the accompanying drawings, the same units / elements are marked with the same reference numerals.

[0014] Unless otherwise specified, the terms (including technical terms) used herein have the commonly understood meanings to those skilled in the art. In addition, it is understood that the terms defined in commonly used dictionaries should be understood to have the same meanings as those in the context of the relevant fields, and should not be understood as idealized or overly formal meanings.

[0015] According to a first aspect of the present invention, a system for amplifying a weak voltage outputted by a voltage divider is provided, referring to Figure 1 As shown, the system includes an inverting amplifier system and a boost system, the inverting amplifier system includes an operational amplifier, a first resistor and a second resistor, the boost system includes a booster, wherein the first resistor and the second resistor are connected in series, and the second resistor is connected in parallel with the operational discharger; the booster has several winding sections wound in the manner of an inductive voltage divider, and a feedback voltage is drawn at the last winding section of the several winding sections, and the feedback voltage is fed back to the non-inverting input terminal of the operational amplifier.

[0016] Specifically, the circuit mainly consists of two parts. The first part is the inverting amplifier part, which is composed of OP1, R1 and R2 in the figure. The second part is the booster. The characteristic of the booster is that the secondary has n windings wound in the manner of an inductive voltage divider, and the voltage drawn from N windings is fed back to the non-inverting input of OP1 (i.e., the operational amplifier). Suppose the input voltage is Vi, the output voltage of the amplifier circuit is Vo, the voltage at the inverting end of the operational amplifier is V-, the output of the booster transformer is Vh, and the feedback voltage is Vf. The error of the operational amplifier circuit composed of R2 and R1 is set to ε1, and the error of the booster output is set to ε2, including the excitation error and the load error. The output winding of the booster is wound in the form of an inductive voltage divider, and Vf is relative to The error is set to ε3. According to the operational amplifier principle, we can get:

[0017]

[0018] Among them, V-=V+=Vf, so:

[0019]

[0020] (1) takes into account the error ε1, then we have

[0021]

[0022] Considering the errors ε2 and ε3, we have:

[0023] Vh=Vo*(1+ε2)(4)

[0024]

[0025] From equations (4) and (5), we can get

[0026]

[0027] Considering that ε2 and ε3 are small, ε2ε3 can be ignored.

[0028]

[0029] Substituting formula (7) into formula (3), we can obtain:

[0030]

[0031] Simplify:

[0032]

[0033]

[0034]

[0035] in

[0036] If n=N is taken in the design, then:

[0037]

[0038] Where K is less than 1, then formula (10) can be approximately equal to:

[0039]

[0040] It can be seen that for the inverting amplifier circuit, the relationship between its input and output is approximately equal to 1, and the error is the negative value of the primary and secondary transmission errors of the rear-end step-up transformer and the feedback signal voltage division error, and is related to the values ​​of resistors R1 and R2.

[0041] Then calculate the output voltage Vh:

[0042] Vh=VoN(1+ε2)

[0043] =ViN[1-K(ε2+ε3)-(ε2+ε3)](1+ε2)

[0044] ≈ViN[1-ε3-K(ε2+ε3)] (12)

[0045] Due to the winding form of the inductive voltage divider, ε3 can generally be controlled within 10ppm. If K is designed to be 0.001, it can be seen that the error of the high-voltage side output of the booster becomes the error of the Vf feedback voltage relative to Vh, and this part of the error is only ε3.

[0046] And for the feedback voltage, the output becomes:

[0047]

[0048] It can be seen from equations (12) and (13) that the boost output is related to the error of the K value and the feedback voltage of the boost output divider. By setting an appropriate K value and controlling the secondary feedback voltage, a boost output within 0.02% can be obtained.

[0049] According to a second aspect of the present invention, a method for amplifying a weak secondary output voltage of a voltage divider is provided. Figure 2 A schematic diagram showing the process of the method is shown in FIG. Figure 2 As shown, the method includes:

[0050] S202: Determine system parameters; and

[0051] S204: Determine the booster voltage and the secondary feedback voltage according to the system parameters, wherein the secondary feedback voltage is a voltage for performing error compensation on the secondary output weak voltage of the voltage divider.

[0052] Optionally, determining system parameters includes: determining the input voltage Vi, the output voltage Vo of the amplifier circuit, the operational amplifier reverse voltage V-, the first error ε1 of the operational amplifier circuit composed of the second resistor R2 and the first resistor R1, the second error ε2 of the booster output, the third error ε3 of the secondary feedback voltage Vf relative to the booster voltage Vh, and the ratio of the first resistor R1 to the second resistor R2; wherein the voltage value of the operational amplifier reverse voltage V- is equal to the voltage value of the secondary feedback voltage Vf.

[0053] Optionally, determining the booster voltage according to the system parameters includes: determining the booster voltage using a calculation formula as follows:

[0054] Vh=VoN(1+ε2)=ViN[1-K(ε2+ε3)-(ε2+ε3)](1+ε2)≈ViN[1-ε3-K(ε2+ε3)]

[0055] Among them, Vh is the boost voltage, Vo is the output voltage of the amplifier circuit, N is the number of sections of the lead winding, K is the ratio of the first resistor R1 to the second resistor R2, Vi is the input voltage, ε2 is the second error of the boost output, and ε3 is the third error of the secondary feedback voltage Vf relative to the boost voltage Vh.

[0056] Optionally, determining the secondary feedback voltage according to the system parameters includes: determining a calculation formula for the secondary feedback voltage as:

[0057] Where Vf is the secondary feedback voltage and n is the number of winding sections.

[0058] According to a third aspect of the present invention, Figure 3As shown, a device 300 for amplifying a weak secondary output voltage of a voltage divider is provided. The device 300 includes: a parameter determination module 310 for determining system parameters; and a voltage determination module 320 for determining a booster voltage and a secondary feedback voltage according to the system parameters, wherein the secondary feedback voltage is a voltage that needs to be amplified by the weak secondary output voltage of the voltage divider.

[0059] Optionally, the parameter determination module 310 includes: a determination submodule, used to determine the input voltage Vi, the amplifier circuit output voltage Vo, the operational amplifier reverse voltage V-, the first error ε1 of the operational amplifier circuit composed of the second resistor R2 and the first resistor R1, the second error ε2 of the booster output, the third error ε3 of the secondary feedback voltage Vf relative to the booster voltage Vh, and the ratio of the first resistor R1 to the second resistor R2; wherein the voltage value of the operational amplifier reverse voltage V- is equal to the voltage value of the secondary feedback voltage Vf.

[0060] Optionally, the voltage determination module 320 includes: a booster voltage determination submodule, wherein the calculation formula for determining the booster voltage is: Vh=VoN(1+ε2)=ViN[1-K(ε2+ε3)-(ε2+ε3)](1+ε2)≈ViN[1-ε3-K(ε2+ε3)], wherein Vh is the booster voltage, Vo is the output voltage of the amplifier circuit, N is the number of sections of the lead winding, K is the ratio of the first resistor R1 to the second resistor R2, Vi is the input voltage, ε2 is the second error of the booster output, and ε3 is the third error of the secondary feedback voltage Vf relative to the booster voltage Vh.

[0061] Optionally, the voltage determination module 320 includes: a secondary feedback voltage determination submodule, which is used to determine the calculation formula of the secondary feedback voltage as follows: Where Vf is the secondary feedback voltage and n is the number of winding sections.

[0062] Therefore, according to the present invention, the secondary low-voltage signal of the voltage divider is safely and accurately amplified through the inverting amplifier part and the booster, meeting the need of using the differential measurement method to calibrate the voltage divider test product. This solves the technical problems in the prior art that the standard electronic voltage divider is used to directly output high voltage through the electronic circuit, which may cause damage to the back-end connection equipment, and the standard electronic voltage divider is used to connect the isolation transformer to amplify the voltage, which will affect the accuracy of the standard secondary output of the voltage divider.

[0063] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0064] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0065] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0066] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0067] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0068] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for amplifying a weak voltage outputted by a voltage divider, characterized in that: include: Determine system parameters; as well as Determine a booster voltage and a secondary feedback voltage according to the system parameters, wherein the secondary feedback voltage is a voltage for performing error compensation on a secondary output weak voltage of a voltage divider; Specifically, the circuit consists of two parts. The first part is the inverting amplifier part, which includes an operational amplifier OP1, a first resistor R1 and a second resistor R2. The second part is a booster. The booster is characterized in that the secondary has n windings wound in the manner of an inductive voltage divider, and the voltage drawn from N windings is fed back to OP1, i.e., the in-phase input terminal of the operational amplifier. The input voltage is Vi, the output voltage of the amplifier circuit is Vo, the voltage at the inverting terminal of the operational amplifier is V-, the output of the booster transformer is Vh, the feedback voltage is Vf, the error of the operational amplifier circuit composed of R2 and R1 is set to ε1, and the error of the booster output is set to ε2, including excitation error and load error. The output winding of the booster is wound in the form of an inductive voltage divider, and Vf is relative to Vh. The error is set to ε3, and according to the operational amplifier principle, we can get: Among them, V-=V+=Vf, so: (1) takes into account the error ε1, then we have Considering the errors ε2 and ε3, we have: Vh=Vo*(1+ε2) (4) From equations (4) and (5), we can get Considering that ε2 and ε3 are small, ε2ε3 can be ignored. Substituting formula (7) into formula (3), we can obtain: Simplify: in If n=N is taken in the design, then: Where K is less than 1, then formula (10) can be approximately equal to: Determining a booster voltage according to the system parameters includes: The calculation formula to determine the boost voltage is: Vh=VoN(1+ε2)=ViN[1-K(ε2+ε3)-(ε2+ε3)](1+ε2)≈ViN[1-ε3-K(ε2+ε3)] (12) Wherein, Vh is the booster voltage, Vo is the output voltage of the amplifier circuit, N is the number of sections of the lead winding, K is the ratio of the first resistor R1 to the second resistor R2, Vi is the input voltage, ε2 is the second error of the booster output, and ε3 is the third error of the secondary feedback voltage Vf relative to the booster voltage Vh; According to the system parameters, determining the secondary feedback voltage includes: The calculation formula to determine the secondary feedback voltage is: Where Vf is the secondary feedback voltage and n is the number of winding sections.

2. The method according to claim 1, characterized in that Determine system parameters, including: Determine the input voltage Vi, the output voltage Vo of the amplifier circuit, the reverse voltage V- of the operational amplifier, the first error ε1 of the operational amplifier circuit composed of the second resistor R2 and the first resistor R1, the second error ε2 of the booster output, the third error ε3 of the secondary feedback voltage Vf relative to the booster voltage Vh, and the ratio of the first resistor R1 to the second resistor R2; The voltage value of the operational amplifier reverse voltage V- is equal to the voltage value of the secondary feedback voltage Vf.

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