High-voltage measurement capacitance compensation system and method

Abstract

The invention discloses a high-voltage measurement capacitance compensation system and method. The device comprises a high-voltage measurement capacitor, an evaluation device and an adjustment module, wherein the high-voltage measurement capacitor is used for performing high-voltage measurement; the evaluation device comprises an auxiliary capacitor connected with the output end of the high-voltage measurement capacitor, the capacitance change value of the auxiliary capacitor is the same as that of the high-voltage measurement capacitor, and the auxiliary capacitor is used for outputting a capacitance change signal when the capacitance changes; and the adjusting module is used for compensating the variable capacitance of the high-voltage measuring capacitor when receiving the capacitance change signal. The evaluation device is arranged, the auxiliary capacitor is connected with the high-voltage measuring capacitor, a signal corresponding to the capacitance change of the high-voltage capacitor can be generated, the capacitance change is compensated through the adjusting module, and the capacitance change of the high-voltage measuring capacitor can be responded and adjusted in time; errors during high-voltage measurement under the condition that interference external influences exist are avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high voltage measurement, and in particular to a high voltage measurement capacitor compensation system and method. BACKGROUND

[0002] In a conventional device using a high voltage measurement capacitor for high voltage measurement, the high voltage measurement capacitor is usually used in combination with a low voltage capacitor to form a capacitor voltage divider, so that the voltage measurement will be substantially error-free only when the capacitance of the high voltage measurement capacitor remains constant. However, since such a high voltage measurement capacitor is usually affected by temperature changes at least, and since the dielectric of the capacitor has temperature dependence, the capacitance of the capacitor will usually change, thereby causing errors of varying sizes in the voltage measurement. SUMMARY

[0003] To solve the problems of the prior art, the present application provides a high voltage measurement capacitor compensation system and method to reduce the voltage measurement errors caused by capacitance changes.

[0004] To this end, the technical solution adopted by the present application is as follows: A high voltage measurement capacitor compensation system is provided, comprising a high voltage measurement capacitor, an evaluation device and an adjustment module. The high voltage measurement capacitor is used for high voltage measurement. The evaluation device comprises an auxiliary capacitor connected to the output end of the high voltage measurement capacitor, the capacitance change value of the auxiliary capacitor being the same as that of the high voltage measurement capacitor, and is used to output a capacitance change signal when the capacitance changes. The adjustment module is used to compensate for the change in capacitance of the high voltage measurement capacitor when the capacitance change signal is received.

[0005] According to the above scheme, the dielectric of the auxiliary capacitor and the dielectric of the high voltage measurement capacitor have the same temperature characteristics or pressure characteristics.

[0006] According to the above scheme, the evaluation device is specifically an oscillator comprising an auxiliary capacitor and a filter connected to the oscillator, the oscillator further comprising an operational amplifier and a resistor, and is used to determine the capacitance change according to the deviation of the oscillator frequency from the nominal frequency.

[0007] According to the above scheme, the dielectric of the auxiliary capacitor and the dielectric of the high voltage measurement capacitor specifically use the same dielectric.

[0008] According to the above scheme, the evaluation device is specifically a bridge circuit including an auxiliary capacitor. One arm of the bridge circuit is composed of an auxiliary capacitor, while the other arms are composed of ordinary capacitors. One diagonal of the bridge circuit is connected to an AC voltage, and the other diagonal is connected to a differential amplifier.

[0009] According to the above scheme, the evaluation device also includes a relay, which is connected to the output terminal of the differential amplifier and is used to generate a signal light change based on the output of the differential amplifier, thereby indicating the capacitance change.

[0010] According to the above scheme, the high-voltage measuring capacitor specifically includes a conductor for carrying high voltage, a conductor electrode, an insulating component, and a protective ring electrode; wherein, the conductor is sealed inside the conductor electrode, the conductor electrode is mounted on the insulating component, and the protective ring electrode is mounted on the surface of the insulating component.

[0011] According to the above scheme, the high-voltage measuring capacitor and the auxiliary capacitor of the evaluation device are arranged in a gas chamber. The adjustment module specifically includes a pump, a compressor and a gas storage tank, which are used to fill the gas chamber where the high-voltage measuring capacitor and the auxiliary capacitor are located to realize the capacitance compensation of the high-voltage measuring capacitor and the auxiliary capacitor.

[0012] A high-voltage measurement capacitor compensation method is also provided, the method being used for compensation in the high-voltage measurement capacitor compensation system described above, the method comprising: High voltage measurement is performed using a high voltage measuring capacitor, and the capacitance change signal output by the evaluation device is monitored in real time. When a change in output capacitance is detected, the capacitance of the high-voltage measuring capacitor is compensated by adjusting the output capacitance change compensation value of the module.

[0013] A computer storage medium is also provided, which stores a computer program executable by a processor, the computer program performing the high-voltage measurement capacitance compensation method described above.

[0014] The beneficial effects of this invention are as follows: By setting up an evaluation device and an adjustment module, the auxiliary capacitor is connected to the high-voltage measuring capacitor, which can generate a signal corresponding to the capacitance change of the high-voltage capacitor caused by external influences. The adjustment module compensates for this capacitance change, which can respond to and adjust the capacitance change of the high-voltage measuring capacitor in a timely manner, avoiding errors when performing high-voltage measurements under the presence of interfering external influences. Attached Figure Description

[0015] Figure 1 This is a schematic flowchart of the high-voltage measurement capacitor compensation method according to an embodiment of the present invention; Figure 2This is a schematic diagram of the structure of a high-voltage measurement capacitor compensation system according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the high voltage measurement capacitor compensation system according to another embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of an evaluation device according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the evaluation device structure according to another embodiment of the present invention.

[0016] In the figure: 1-Gas chamber; 2-High voltage measuring capacitor; 3-Conductor; 4-Conductor electrode; 5-Insulating component; 6-First protective ring electrode; 7-Second protective ring electrode. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] To address the problem of large voltage measurement errors caused by capacitance variations in existing high-voltage measurements, this invention provides a high-voltage measurement capacitance compensation system, comprising: a high-voltage measurement capacitor, an evaluation device, and an adjustment module; Among them, the high-voltage measuring capacitor is used for high-voltage measurement; The evaluation device includes an auxiliary capacitor connected to the output terminal of the high-voltage measuring capacitor. The capacitance change value of the auxiliary capacitor is the same as that of the high-voltage measuring capacitor, and it is used to output a capacitance change signal when the capacitance changes. The adjustment module is used to compensate for the change in capacitance of the high-voltage measuring capacitor when a capacitance change signal is received.

[0019] To ensure the accuracy of capacitance change measurement, the dielectric of the auxiliary capacitor should have the same temperature and / or pressure characteristics as the high-voltage capacitor. Therefore, an auxiliary capacitor with the same dielectric as that used in the high-voltage measuring capacitor can be used.

[0020] In addition, the auxiliary capacitor should be designed so that the capacitance change due to thermal expansion is proportional to the capacitance change of the high-voltage measuring capacitor.

[0021] In a preferred embodiment, a high-voltage measuring capacitor is connected to a low-voltage capacitor, and the high-voltage measuring capacitor and the low-voltage capacitor are combined to form a capacitive voltage divider. An auxiliary capacitor of the evaluation device is connected to the capacitive voltage divider, so that the capacitance change of the fine-tuning capacitor changes with the signal of the evaluation device. This change, in turn, can compensate for the effect of the capacitance change of the high-voltage measuring capacitor on the voltage division ratio of the capacitive voltage divider.

[0022] Specifically, the adjustment module in this embodiment employs an amplifier circuit, which increases or decreases the gain at the output of the amplifier circuit based on the signal from the evaluation device.

[0023] In a preferred embodiment, when the evaluation device is used only to signal the capacitance change of the high-voltage measuring capacitor, the evaluation device also includes an oscillator with an auxiliary capacitor as the oscillator frequency determination component. In this case, the frequency deviation of the oscillator relative to the nominal frequency represents a measure of the capacitance change.

[0024] In a preferred embodiment, when the evaluation device is used to signal and compensate for capacitance changes in a high-voltage measuring capacitor, a bridge circuit can be used as the evaluation device. One arm of the bridge circuit consists of an auxiliary capacitor, while the other arms consist of other capacitors. Furthermore, one diagonal of the bridge circuit is connected to an AC voltage, and the other diagonal is connected to a differential amplifier. The output of the differential amplifier represents the signal from the evaluation device. This output can, in turn, be used both to signal and compensate for capacitance changes.

[0025] In addition, this embodiment of the invention also provides a high-voltage measurement capacitor compensation method, used for capacitor compensation in the high-voltage measurement capacitor compensation system described in this embodiment of the invention, such as... Figure 1 As shown, the method includes: S1. High voltage measurement is performed using a high voltage measuring capacitor, and the capacitance change signal output by the evaluation device is monitored in real time.

[0026] S2. When a change in output capacitance is detected, the capacitance of the high-voltage measuring capacitor is compensated by adjusting the output capacitance change compensation value of the module.

[0027] In addition, embodiments of the present invention also provide a computer-readable storage medium, such as flash memory, hard disk, multimedia card, card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, disk, optical disk, server, App application store, etc., which stores a computer program, and the program implements the corresponding function when executed by a processor. The computer-readable storage medium of this embodiment is used in a high-voltage measurement capacitance compensation system, and when executed by a processor, it implements the high-voltage measurement capacitance compensation method of the method embodiment.

[0028] This invention provides a high-voltage measurement capacitance compensation system and method. By setting up an evaluation device and an adjustment module, an auxiliary capacitor is connected to a high-voltage measurement capacitor. This generates a signal corresponding to the capacitance change of the high-voltage capacitor caused by external influences. The adjustment module compensates for this capacitance change, enabling timely response and adjustment to the capacitance change of the high-voltage measurement capacitor and avoiding errors during high-voltage measurement under the influence of interfering external factors.

[0029] Example 2 This invention provides a high-voltage measurement capacitor compensation system, such as... Figure 2 As shown, the gas chamber 1 contains a high-voltage measuring capacitor 2, which includes a high-voltage conductor 3 enclosed within a cylindrical conductor electrode 4. The conductor electrode 4 is mounted on a cast resin insulating component 5, each of which has a protective ring electrode on its circular surface, namely a first protective ring electrode 6 and a second protective ring electrode 7. The cylindrical conductor electrode 4, the first protective ring electrode 6, and the second protective ring electrode 7 can be formed by applying a conductive coating to the insulating component 5. In addition, another conductive coating is supported on the outer surface of the insulating component 5, and this conductive coating is grounded through a line 9. The insulating component 5 with the aforementioned conductive coating can be housed within a section of a fully insulated, metal-encapsulated high-voltage switchgear device, in which case the gas chamber 1 is formed from the interior of the high-voltage switchgear device.

[0030] Furthermore, the cylindrical electrode 4 is connected to a low-voltage capacitor 11 via line 10, which, together with the high-voltage measuring capacitor 2, forms a capacitive voltage divider. Preferably, after amplification, a voltage proportional to the high voltage can be obtained from the output terminal 12.

[0031] Simultaneously, an auxiliary capacitor 13 is arranged within the gas chamber 1, adjacent to the high-voltage measuring capacitor 2. The auxiliary capacitor 13 is designed similarly to the high-voltage measuring capacitor 2, using an internal conductor 14 as one electrode and a cylindrical external electrode as the other. Connecting lines 16 and 17 connect the auxiliary capacitor 13 to a low-voltage bridge circuit, which, in addition to capacitor 13 in one arm, includes other capacitors 18, 19, and 20 in the other arms. The auxiliary capacitor 13 and the other capacitors 18 to 20 are arranged such that the auxiliary capacitor 13 and the other capacitor 20 are on one side of the bridge, while the other capacitors 18 and 19 are on the other side. An AC voltage from the AC voltage source 23 is applied to the diagonal of a bridge formed by circuit nodes 21 and 22. By arranging capacitor 13 in this way and applying an AC signal, a signal voltage Us representing the capacitance change of the high-voltage capacitor 2 can be obtained from the endpoints 26 and 27 of the other diagonal formed by bridge circuit nodes 24 and 25. The signal can then be used to generate a visual or auditory signal to draw the operator's attention to changes in capacitance.

[0032] Specifically, the appearance of voltage at terminals 26 and 27 of the bridge circuit indicates that the balance of the bridge circuit has been disrupted by the capacitance change of auxiliary capacitor 13. However, the capacitance change of auxiliary capacitor 13 only occurs when there is also a temperature change, a pressure change, or a change in the gas mixture in gas chamber 1. In all these cases, the capacitance of the high-voltage measuring capacitor 2, composed of conductor 3 and conductor electrode 4, will change accordingly to the capacitance change of auxiliary capacitor 13. Therefore, the voltage Us generated by the latter capacitance change will indicate the former capacitance change. Such a voltage can thus be used to signal that the voltage measured at terminal 12 of low-voltage capacitor 11 is incorrect because the capacitance change of capacitor 2 interferes with the voltage division ratio, and capacitance compensation is required.

[0033] Example 3 Based on Embodiment 2, this embodiment of the invention provides a high-voltage measurement capacitor compensation system, the difference being: as follows Figure 3 As shown, this embodiment adds a device for compensating for capacitance changes in the high-voltage measuring capacitor. More specifically, a device related to... Figure 1A second high-voltage measuring capacitor 30, similar to the high-voltage measuring capacitor 2, is placed in the second air chamber 31. Connected to the second high-voltage measuring capacitor 30 is a second low-voltage capacitor 32. These two capacitors together form a capacitive voltage divider. Connected to the second low-voltage capacitor 32 is a preamplifier, which consists of an operational amplifier 33, followed by a power amplifier 34 consisting of another operational amplifier. Connected to the output of the power amplifier 34 is the primary winding 35 of an output transformer 36, and the secondary winding 37 is connected to a load 38.

[0034] A second auxiliary capacitor 39 is arranged adjacent to the second high-voltage measuring capacitor 30 within the second gas chamber 31, and its design is similar to that of the second high-voltage measuring capacitor 30. It can be seen that the second auxiliary capacitor 39 forms part of a bridge circuit of the evaluation device 40, and specifically, it is connected in series with another capacitor 41 on one side of the bridge circuit. Other capacitors 42 and 43 are arranged on the other side of the bridge circuit.

[0035] The output voltage of power amplifier 34 is connected across a diagonal formed by circuit nodes 44 and 45 of the bridge circuit via connecting line 46. Connected to the other diagonal 47 and 48 of the bridge circuit is an operational amplifier designed as a differential amplifier 49. The output 50 of differential amplifier 49 measures the amount of capacitance change of the second auxiliary capacitor 39, and its phase measures the type of capacitance change, i.e., whether the change is positive or negative relative to an assumed starting or reference value.

[0036] Furthermore, the output of the differential amplifier 49 is supplied to one input terminal 52 of the power amplifier 34 via a resistor 51. The output of the preamplifier 33 is also connected to this input terminal, and the other input terminal 53 of the power amplifier 34 is grounded. Therefore, it can be shown that an output quantity or voltage will appear at the output 54 of the power amplifier 34, in which the capacitance change of the auxiliary capacitor 39, and consequently the capacitance change of the high-voltage capacitor 30, are compensated. Thus, this output voltage will be proportional to the voltage measured by the high-voltage measuring capacitor 30, regardless of the capacitance change of that capacitor.

[0037] In summary, the voltage obtained from load 38 will be correlated with the measured high voltage through a constant transformation ratio.

[0038] Preferably, a relay 56 can also be connected to the output 50 of the differential amplifier 49 via a connecting line 55 (shown as dashed). In this case, when the capacitance of the high-voltage measuring capacitor 30 changes, the relay will actuate, and its contacts 57 will illuminate the indicator light 58 by connecting it to the battery 59, thereby alerting relevant personnel to the change in the capacitance of the high-voltage measuring capacitor 30.

[0039] Example 4 Based on Embodiment 3, this embodiment of the invention provides a high-voltage measurement capacitance compensation system, the difference being that: the evaluation device uses, as in... Figure 4 The design shown includes a third auxiliary capacitor 60 and its associated high-voltage measuring capacitor (not shown) located within a third gas chamber 61. The capacitance change of the third auxiliary capacitor 60 is compared with the capacitance change of another capacitor 62, which serves as a reference capacitor, in a comparator or evaluation circuit 63. This evaluation circuit 63 is then connected to a device 64 consisting of a pump and a compressor. The device 64 pumps gas from a gas tank 65 into the gas chamber 61 as needed, thereby compensating for capacitance changes in the capacitor 60 and its associated high-voltage capacitor. Furthermore, from a measurement perspective, the pressure within the gas chamber 61 is controlled within maximum permissible values ​​by a pressure monitor 66.

[0040] Example 5 Based on Embodiment 3, this embodiment of the invention provides a high-voltage measurement capacitance compensation system, the difference being that: the evaluation device uses, as in... Figure 5 In the design shown, an auxiliary capacitor 70, an operational amplifier 71, and a resistor 72 constitute an RC oscillator. This oscillator is followed by a filter 73 tuned to the nominal frequency, so that a voltage appears at the filter's output only when the capacitance of the auxiliary capacitor 70 changes, and consequently, the capacitance of the associated high-voltage measuring capacitor also changes. For example, this signal can also be fed to an alarm device as shown in Embodiment 2 to signal changes in the capacitance of the high-voltage capacitor.

[0041] It should be noted that, depending on the implementation needs, the various steps / components described in this application can be broken down into more steps / components, or two or more steps / components or parts of the operation of steps / components can be combined into new steps / components to achieve the purpose of this invention.

[0042] The order of the steps in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0043] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A high-voltage measurement capacitor compensation system, characterized in that, include: High-voltage measuring capacitors, evaluation devices, and regulation modules; Among them, the high-voltage measuring capacitor is used for high-voltage measurement; The evaluation device includes an auxiliary capacitor connected to the output terminal of the high-voltage measuring capacitor. The capacitance change value of the auxiliary capacitor is the same as that of the high-voltage measuring capacitor, and it is used to output a capacitance change signal when the capacitance changes. The adjustment module is used to compensate for the change in capacitance of the high-voltage measuring capacitor when a capacitance change signal is received.

2. The high-voltage measurement capacitor compensation system according to claim 1, characterized in that, The dielectric of the auxiliary capacitor has the same temperature or pressure characteristics as the dielectric of the high-voltage measuring capacitor.

3. The high-voltage measurement capacitor compensation system according to claim 1, characterized in that, The evaluation device specifically comprises an oscillator including an auxiliary capacitor and a filter connected to the oscillator. The oscillator also includes an operational amplifier and a resistor, used to determine the capacitance change based on the deviation of the oscillator frequency from the nominal frequency.

4. The high-voltage measurement capacitor compensation system according to claim 2, characterized in that, The dielectric of the auxiliary capacitor is the same as that of the high-voltage measuring capacitor.

5. The high-voltage measurement capacitor compensation system according to claim 1, characterized in that, The evaluation device is specifically a bridge circuit including an auxiliary capacitor. One arm of the bridge circuit is composed of an auxiliary capacitor, while the other arms are composed of ordinary capacitors. One diagonal of the bridge circuit is connected to an AC voltage, and the other diagonal is connected to a differential amplifier.

6. The high-voltage measurement capacitor compensation system according to claim 5, characterized in that, The evaluation device also includes a relay connected to the output of the differential amplifier, which is used to generate a signal light change based on the output of the differential amplifier, thereby indicating the capacitance change.

7. The high-voltage measurement capacitor compensation system according to claim 1, characterized in that, The high-voltage measuring capacitor specifically includes a conductor for carrying high voltage, conductor electrodes, insulating components, and protective ring electrodes; wherein the conductor is sealed inside the conductor electrodes, the conductor electrodes are mounted on the insulating components, and the protective ring electrodes are mounted on the surface of the insulating components.

8. The high-voltage measurement capacitor compensation system according to claim 1, characterized in that, The high-voltage measuring capacitor and the auxiliary capacitor of the evaluation device are arranged in a gas chamber. The adjustment module specifically includes a pump, a compressor and a gas storage tank, which are used to fill the gas chamber where the high-voltage measuring capacitor and the auxiliary capacitor are located to realize the capacitance compensation of the high-voltage measuring capacitor and the auxiliary capacitor.

9. A high-voltage measurement capacitor compensation method, characterized in that, The method is used for compensation in the high-voltage measurement capacitor compensation system according to any one of claims 1-8, and the method includes: High voltage measurement is performed using a high voltage measuring capacitor, and the capacitance change signal output by the evaluation device is monitored in real time. When a change in output capacitance is detected, the capacitance of the high-voltage measuring capacitor is compensated by adjusting the output capacitance change compensation value of the module.

10. A computer storage medium, characterized in that, It contains a computer program that can be executed by a processor, which performs the high-voltage measurement capacitor compensation method as described in claim 9.

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