Online Monitoring Method and Device for Actual Action Timing of Vacuum On-Load Tap Changer

Abstract

The present invention proposes a method and device for online monitoring the actual operation sequence of a vacuum on-load tap changer. The method includes: controlling the operation of the vacuum on-load tap changer according to a test operation sequence to gradually adjust the operating voltage of the on-load transformer; wherein the vacuum on-load tap changer is provided with a preset voltage sensor and a current sensor; recording a voltage curve obtained by the preset voltage sensor of the vacuum on-load tap changer, and recording a current curve obtained by the preset current sensor of the vacuum on-load tap changer; and determining the actual operation sequence of the vacuum on-load tap changer in response to the test operation sequence based on the voltage curve obtained by the voltage sensor and the current curve obtained by the current sensor. In this way, the actual operation sequence of the vacuum on-load tap changer can be obtained while the operating voltage of the on-load transformer is gradually adjusted.

Description

Technical Field

[0001] The present invention relates to the technical field of online monitoring of vacuum on-load tap changers, and in particular to a method and device for online monitoring of the actual action sequence of vacuum on-load tap changers. Background Art

[0002] The operating sequence is a key parameter that characterizes the operating status of a transformer's vacuum on-load tap-changer. However, the complex internal structure of a vacuum on-load tap-changer makes it difficult to monitor its operating sequence by installing a displacement sensor or acceleration sensor and monitoring the circuit breaker contact travel.

[0003] To this end, a vacuum on-load tap-changer (OLTC) timing test is typically performed after a transformer power outage. Specifically, after the transformer is powered off, a 24V DC test voltage is used to control the vacuum on-load tap-changer's switching position. This allows the on-load tap-changer to monitor its offline timing and determine its offline operating status.

[0004] There is a significant discrepancy between the operating sequence of the vacuum on-load tap-changer tested after a transformer outage and the actual operating sequence during load operation. This is because, during the post-outage testing scenario, the vacuum on-load tap-changer is not under load, and the test voltage differs significantly from the operating voltage during load operation.

[0005] Therefore, there is an urgent need to provide a technical solution for online monitoring of the action sequence of the vacuum on-load tap-changer of the running transformer. Summary of the Invention

[0006] In view of this, the present invention proposes a method and device for online monitoring of the actual operation sequence of a vacuum on-load tap-changer, aiming to solve the problem in the prior art that the actual operation sequence of a vacuum on-load tap-changer during on-load operation of a transformer cannot be monitored.

[0007] In a first aspect, the present invention provides a method for online monitoring of the actual operation sequence of a vacuum on-load tap changer, comprising:

[0008] According to the test action sequence, the vacuum on-load tap-changer is controlled to operate so as to gradually adjust the operating voltage of the on-load transformer; wherein the vacuum on-load tap-changer is pre-set with a voltage sensor and a current sensor;

[0009] Recording a voltage curve obtained by a preset voltage sensor of the vacuum on-load tap changer, and recording a current curve obtained by a preset current sensor of the vacuum on-load tap changer;

[0010] An actual action sequence of the vacuum on-load tap changer in response to the test action sequence is determined according to the voltage curve acquired by the voltage sensor and the current curve acquired by the current sensor.

[0011] Furthermore, the vacuum on-load tap changer includes a switch module and a tap selector. In response to the action of the tap selector, the switch module is actuated and the operating voltage of the on-load transformer is adjusted step by step.

[0012] The switch module includes an even-side transition circuit, an odd-side transition circuit, an even-side switching contact, an odd-side switching contact, an even-side main contact, and an odd-side main contact;

[0013] The even-number side transition circuit includes a first vacuum tube and a second vacuum tube, and the odd-number side transition circuit includes a third vacuum tube and a fourth vacuum tube;

[0014] Correspondingly, the test action sequence includes theoretical opening and closing actions for the even-numbered main contacts, the odd-numbered main contacts, the even-numbered switching contacts, the odd-numbered switching contacts and / or each vacuum tube.

[0015] Furthermore, the vacuum on-load tap changer is provided with a preset voltage sensor and a current sensor, including:

[0016] A current sensor provided in the even-side transition circuit is used to obtain a current curve flowing through the first vacuum tube or the second vacuum tube;

[0017] A current sensor provided in the odd-side transition circuit, for obtaining a current curve flowing through the third vacuum tube or the fourth vacuum tube;

[0018] A voltage sensor provided in the even-side transition circuit is used to obtain a voltage curve across the second vacuum tube;

[0019] The voltage sensor provided in the odd-side transition circuit is used to obtain the voltage curve across the third vacuum tube.

[0020] Furthermore, the test action sequence is used to switch from connecting the even-numbered tap via the even-side transition circuit to connecting the adjacent odd-numbered tap via the odd-side transition circuit; or

[0021] The test action sequence is used to switch from connecting an odd-numbered tap via an odd-side transition circuit to connecting an adjacent even-numbered tap via an even-side transition circuit;

[0022] When the even-numbered tap is connected via the even-numbered transition circuit, the states of the switch module include: the even-numbered main contact is closed, the even-numbered transfer contact is closed; the first vacuum tube is closed, the second vacuum tube is closed; the odd-numbered main contact is open, the odd-numbered transfer contact is open; the third vacuum tube is open, the fourth vacuum tube is open;

[0023] Among them, when the odd-numbered tap is connected through the odd-numbered side transition circuit, the status of the switching switch module includes: the odd-numbered side main contact is closed, the odd-numbered side conversion contact is closed; the third vacuum tube is closed, the fourth vacuum tube is closed; the even-numbered side main contact is open, the even-numbered side conversion contact is open; the first vacuum tube is open, and the second vacuum tube is open.

[0024] Furthermore, determining an actual action sequence of the vacuum on-load tap changer in response to the test action sequence based on the voltage curve acquired by the voltage sensor and the current curve acquired by the current sensor includes:

[0025] determining, based on the acquired current curve flowing through the first vacuum tube, an actual breaking action moment of the main contact on the even number side or a failure of the main contact on the even number side to perform the breaking action;

[0026] determining, based on the obtained voltage curve across the third vacuum tube, the actual closing action moment of the odd-numbered side switching contact or the failure of the odd-numbered side switching contact to perform the closing action;

[0027] determining an actual breaking action time of the first vacuum tube according to the obtained current curve flowing through the second vacuum tube;

[0028] determining an actual closing action time of the third vacuum tube according to the acquired current curve flowing through the third vacuum tube;

[0029] determining an actual breaking action time of the second vacuum tube according to the obtained voltage curve across the second vacuum tube;

[0030] determining an actual closing action time of the fourth vacuum tube according to the obtained current curve flowing through the fourth vacuum tube;

[0031] determining, based on the obtained voltage curve across the second vacuum tube, the actual breaking action moment of the even-numbered side switching contact or the failure of the even-numbered side switching contact to perform the breaking action;

[0032] The actual closing action moment of the odd-side main contact is determined according to the obtained current curves flowing through the first vacuum tube, the second vacuum tube, the third vacuum tube, and the fourth vacuum tube.

[0033] Furthermore, it also includes:

[0034] Based on the theoretical action times recorded in the test action sequence and the determined actual opening and closing action times, determine any one or more of the following:

[0035] Whether the even-side changeover contact, odd-side changeover contact, even-side main contact or odd-side main contact operates correctly at the set time;

[0036] Check whether the changeover contacts on the even side, the changeover contacts on the odd side, the main contacts on the even side or the main contacts on the odd side operate correctly after a delay.

[0037] Furthermore, the vacuum on-load tap changer further comprises: a driving mechanism;

[0038] Based on the theoretical action times recorded in the test action sequence and the determined actual opening and closing action times, determine any one or more of the following:

[0039] The driving mechanism is stuck;

[0040] The driving mechanism slides;

[0041] The drive mechanism refuses to move.

[0042] In a second aspect, the present invention provides an online monitoring device for the actual operation sequence of a vacuum on-load tap changer, which is used to perform the online monitoring method for the actual operation sequence of a vacuum on-load tap changer as described in the first aspect, comprising:

[0043] A control module is used to control the operation of the vacuum on-load tap-changer according to the test action sequence to gradually adjust the operating voltage of the on-load transformer; wherein the vacuum on-load tap-changer is preset with a voltage sensor and a current sensor;

[0044] a measuring module, configured to record a voltage curve obtained by a preset voltage sensor of the vacuum on-load tap changer, and a current curve obtained by a preset current sensor of the vacuum on-load tap changer;

[0045] The processing module is configured to determine an actual action sequence of the vacuum on-load tap changer in response to the test action sequence according to the voltage curve acquired by the voltage sensor and the current curve acquired by the current sensor.

[0046] In a third aspect, the present invention provides a terminal comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method described in the first aspect.

[0047] In a fourth aspect, the present invention provides a computer storage medium storing computer-executable instructions, wherein the computer-executable instructions are used to execute the method described in the first aspect.

[0048] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not intended to limit the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0050] Figure 1 Schematic diagram of the flow of a method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to an embodiment of the present invention;

[0051] Figure 2 Schematic diagram of the electrical principle of a vacuum on-load tap-changer in the method for online monitoring the actual operation sequence of a vacuum on-load tap-changer according to an embodiment of the present invention;

[0052] Figure 3 This is a schematic diagram of a test action sequence in the method for online monitoring of the actual action sequence of a vacuum on-load tap-changer according to an embodiment of the present invention;

[0053] Figure 4 This is a schematic diagram of the electrical principle when the tap changer connects an even-numbered tap through an even-numbered side transition circuit in the method for online monitoring the actual operation sequence of a vacuum on-load tap changer according to an embodiment of the present invention;

[0054] Figure 5 This is a schematic diagram of the electrical principle when the main contact A on the even side of the switch module is disconnected when the tap changer switches the tapping on the even side to the odd side in the online monitoring method for the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0055] Figure 6 Schematic diagram of a current curve for determining the breaking action moment of the main contact A in the online monitoring method for the actual action sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0056] Figure 7 This is a schematic diagram of the electrical principle of the switching contact J2 of the switching switch module closing when the tap changer switches the tapping from the even side to the odd side in the online monitoring method for the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0057] Figure 8 Schematic diagram of a voltage curve for determining the closing action moment of the transfer contact J2 in the online monitoring method for the actual action sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0058] Figure 9 This is a schematic diagram of the electrical principle when the first vacuum tube K1 of the switching switch module is disconnected when the tap changer switches the tapping from the even side to the odd side in the online monitoring method for the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0059] Figure 10Schematic diagram of a current curve for determining the breaking action moment of the first vacuum tube K1 in the online monitoring method for the actual action sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0060] Figure 11 This is a schematic diagram of the electrical principle of the third vacuum tube K3 of the switching switch module being closed when the tap changer switches the tap from the even side to the odd side in the online monitoring method for the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0061] Figure 12 Schematic diagram of a current curve for determining the closing action moment of the third vacuum tube K3 in the online monitoring method for the actual action sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0062] Figure 13 This is a schematic diagram of the electrical principle when the second vacuum tube K2 of the switching switch module is disconnected when the tap changer switches the tapping of the even-numbered side to the odd-numbered side in the online monitoring method of the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0063] Figure 14 Schematic diagram of a voltage curve for determining the breaking action moment of the second vacuum tube K2 in the online monitoring method for the actual action sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0064] Figure 15 This is a schematic diagram of the electrical principle when the fourth vacuum tube K4 of the switching switch module is closed when the tap changer switches the tap from the even side to the odd side in the online monitoring method for the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0065] Figure 16 Schematic diagram of a current curve for determining the closing action moment of the fourth vacuum tube K4 in the online monitoring method for the actual action sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0066] Figure 17 This is a schematic diagram of the electrical principle of the switching contact J1 of the switch module being disconnected when the tap changer switches the tapping from the even side to the odd side in the method for online monitoring the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0067] Figure 18 Schematic diagram of the voltage curve principle for determining the switching contact J1 opening action moment in the online monitoring method for the actual action sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0068] Figure 19 This is a schematic diagram of the electrical principle of the case where the main contact B of the switch module is closed when the tap changer switches the tap from the even-numbered side to the odd-numbered side in the online monitoring method for the actual operation sequence of the vacuum on-load tap changer according to an embodiment of the present invention;

[0069] Figure 20 Schematic diagram of a current curve for determining the closing moment of the main contact B in the online monitoring method for the actual operation sequence of the vacuum on-load tap-changer according to an embodiment of the present invention;

[0070] Figure 21 A schematic structural diagram of an online monitoring device for the actual operation sequence of a vacuum on-load tap-changer provided in an embodiment of the present invention;

[0071] Figure 22 Schematic diagram of the composition of a terminal to which the method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to an embodiment of the present invention is applied;

[0072] Figure 23 Schematic diagram of a program product using the method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to an embodiment of the present invention. DETAILED DESCRIPTION

[0073] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, unless there is a conflict, the embodiments of the present disclosure and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0074] Three-phase vacuum on-load tap-changer is used for three-phase AC transformer, and single-phase vacuum on-load tap-changer is used for single-phase AC transformer. Figure 2 As shown in Figure 1, a vacuum on-load tap-changer can adjust the number of turns of the voltage regulating winding connected to the main circuit in steps (assuming the number of turns of the main winding remains unchanged), thereby adjusting the voltage ratio of the transformer and ultimately achieving voltage regulation. Typically, the gear positions or gear numbers are continuous, and the transformer gears are continuously switched to achieve step-by-step regulation. Naturally, during step-by-step regulation, the transformer voltage ratio changes in steps rather than continuously.

[0075] Failures in vacuum on-load tapchangers installed on AC power transformers or converter transformers typically occur during or after the switching process. Some of these failures are caused by mechanical component defects (such as deformation or looseness), which lead to abnormal switching timing and, in turn, electrical circuit failures. For example, if a tapchanger contact is loose, the actual timing of the tapchanger's operation may deviate significantly from the theoretical timing specified in the technical specifications. Therefore, by comparing the actual and theoretical timings, we can determine whether the tapchanger has deformed or loose contacts or an electrical circuit anomaly.

[0076] The present invention provides a technical solution for online monitoring of the actual operation sequence of a vacuum on-load tapchanger, including a method and device for online monitoring of the actual operation sequence of the vacuum on-load tapchanger. Based on the voltage and current of the transient response of the transition circuit during the continuous switching of transformer gears, the method determines the opening and closing times of each switch in the vacuum on-load tapchanger, thereby generating the actual operation sequence. This allows direct monitoring of the operating status or key status information of the vacuum on-load tapchanger, improving the ability to control the operating status of the vacuum on-load tapchanger and resolving the existing technical problem of being unable to monitor the actual operation sequence of the vacuum on-load tapchanger during operation.

[0077] Specifically, key status information includes whether the timing is abnormal and whether the timing meets technical requirements. For example, by comparing the actual action timing with the preset test action timing, such as the symmetry of the timing when main contact A switches to main contact B and when main contact B switches to main contact A, it is possible to determine which transition circuit has a known type of defect. It should be understood that the relevant technical documents record the known types of defects corresponding to various types of timing anomalies or timing differences, which can be easily searched and determined, and will not be further detailed here.

[0078] like Figure 2 As shown in the central part of the transformer winding, several taps are drawn out ( Figure 2 After the load current is cut off (9 taps are shown), by switching from one tap to the next (hereinafter referred to as switching taps) without interrupting the load current, the effective number of turns connected to the voltage regulating winding can be changed, thereby changing the voltage ratio of the transformer and achieving voltage regulation.

[0079] Specifically, during the tap change process, the vacuum on-load tap-changer simultaneously connects (also known as bridges) the two taps involved in the changeover for a very short period of time to ensure load current continuity. To achieve this, an impedance (such as a resistor R) is connected in series between the two bridged taps to limit circulating current and prevent inter-tap short circuits. This circuit is called a transition circuit, and the impedance is called a transition impedance.

[0080] like Figure 2 As shown on the right, the transition circuit can adopt a 2+2 structure. The transition circuit includes an even-side transition circuit connected to the first tap (e.g., even-numbered tap 6) and an odd-side transition circuit connected to the second tap (e.g., odd-numbered tap 7). The even-side transition circuit includes at least one transition resistor branch and at least one transition branch; the odd-side transition circuit includes at least one transition resistor branch and at least one transition branch. Together, the even-side and odd-side transition circuits, along with the at least one transition resistor branch and at least one transition branch, form a 2+2 structure. Naturally, the branch with a transition resistor is referred to as the transition resistor branch. The branch without a transition resistor is referred to as the transition branch.

[0081] In high-voltage power systems, vacuum circuit breakers are core components of vacuum circuit breakers, extinguishing arcs in a vacuum environment and enabling rapid circuit interruption. Their structure consists of two metal contacts, which utilize the high insulation properties of a vacuum to suppress arcs when interrupting current. Vacuum circuit breakers control circuit continuity by opening and closing contacts, and their arc-extinguishing capability relies on the high dielectric strength of the vacuum environment. When the current is interrupted, the vacuum environment lacks ionization, rapidly extinguishing the arc and preventing contact erosion.

[0082] like Figure 2 As shown on the right, vacuum switching tubes are installed in the transition resistor branch and the transition branch, respectively. These tubes are used to connect or disconnect the transition resistor branch and the transition branch from the main circuit in a very short time during the tap change process. Naturally, the branch with a vacuum tube connected in series with the transition resistor is called the transition resistor branch. The branch with only the vacuum tube and no transition resistor is called the transition branch.

[0083] like Figure 2 As shown on the right, the transition resistor in the transition resistor branch is connected to a tap (such as tap 6 or 7) on its distal side, and the vacuum tube in the transition resistor branch is connected to a changeover contact (such as J1 or J2) on its proximal side. The vacuum tube in the transition branch is connected to a tap (such as tap 6 or 7) and a changeover contact (such as J1 or J2) on its proximal and distal sides, respectively.

[0084] like Figure 2 As shown, the transition circuit also includes a main contact branch. When the main contact is closed, one end of the main contact is used to connect to the tap (such as tap 6 or tap 7), and the other end of the main contact is connected to the transfer contact (such as J1 or J2).

[0085] In this way, within each transition circuit, the main contact branch, transition resistor branch, and transition branch are connected in parallel between the tap and the changeover contact, changing the effective number of turns connected to the winding, thereby changing the transformer's voltage ratio and achieving voltage regulation. During the tap switching process, the load current is continuous during the transition from connection to tap 6 to the next tap 7, preventing inter-tap short circuits.

[0086] With reference to the above description, after adopting the 2+2 structure, the switch module includes at least 4 vacuum tubes, at least 2 main contacts, and at least 2 switching contacts. Figure 2 As shown, the diverter switch module includes four vacuum tubes K1, K2, K3, and K4 that can be opened or closed; main contacts A and B; and transfer contacts J1 and J2. The arc extinguishing capabilities of main contacts A, B, J1, and J2 are limited, and arc extinguishing is primarily achieved by the four vacuum tubes K1 through K4.

[0087] Since the voltage regulating winding has multiple taps, such as Figure 2As shown on the left side of the diagram, the vacuum on-load tapchanger is equipped with a tap selector and a polarity selector. The tap selector includes an upper tap selector contact layer and a lower tap selector contact layer, each of which is connected to the winding taps via even-numbered or odd-numbered taps. The upper tap selector contact layer is used to connect the contacts to even-numbered taps; the even-numbered taps include 0, 2, 4, 6, and 8; the lower tap selector contact layer is used to connect the contacts to odd-numbered taps; the odd-numbered taps include 1, 3, 5, and 7. After the tap selector is activated, the adjacent taps to be immediately changed are pre-connected according to the tapping sequence and bear part of the continuous load. When and only when passing through the 9th gear, the polarity selector is activated, reversing the polarity. Specifically, from gears 1 to 8, the voltage regulating winding is connected to the transformer in the forward direction; from gears 10 to 17, the voltage regulating winding is connected to the transformer in the reverse direction. In this way, the forward access or reverse access is controlled by the polarity selector, and the same voltage regulating winding and 9 taps are reused to form a total of 17 gears. Among them, when in gear 9, it is equivalent to the voltage regulating winding not being connected, and the voltage regulating part is 0.

[0088] With reference to the above description, the vacuum on-load tap-changer for transformers includes a switching switch module, a tap selector, and a polarity selector. In terms of structure and relative position, the switching switch module generates an arc when switching the load current, which will deteriorate the oil quality. Therefore, it is usually set in a separate insulating cylinder to isolate it from the oil in the transformer tank. The tap selector and the polarity selector are usually immersed in the transformer tank, such as the tap selector and the polarity selector are located above the switching switch module. The vacuum on-load tap-changer is also provided with a drive mechanism, which is usually arranged on the outside of the transformer, such as the side wall outside the transformer tank. The drive mechanism drives the contacts, tap selector and polarity selector in the switching switch module to operate, switching the voltage regulating winding from one tap to the next tap, thereby realizing continuous step-by-step voltage regulation.

[0089] Specifically, the drive mechanism, serving as the power source for the operation of the switching module, tap selector, and polarity selector, is typically equipped with auxiliary devices such as limit switches, safety interlocks, position indicators, counters, and signal generators. For example, an electric drive mechanism may include vertical axis gears, motor belts, vertical and horizontal axes, etc. Specifically, in response to preset program instructions or timing, the drive mechanism actuates the contacts, tap selector, and polarity selector in the transition circuit, achieving switching from one tap to the next (hereinafter referred to as switching taps) without interrupting the load current. This will not be further described. Figure 2 The technical indicators of a certain type of vacuum on-load tap-changer shown include: maximum rated through-current 600A, maximum step voltage 4000V, and rated step capacity 1500kVA.

[0090] like Figure 1 As shown, the present invention proposes an online monitoring method for the actual operation sequence of a vacuum on-load tap changer, comprising:

[0091] S100: Controlling the vacuum on-load tap-changer to operate according to the test action sequence to gradually adjust the operating voltage of the on-load transformer; wherein the vacuum on-load tap-changer is pre-set with a voltage sensor and a current sensor;

[0092] S200: Recording a voltage curve obtained by a preset voltage sensor of the vacuum on-load tap changer, and recording a current curve obtained by a preset current sensor of the vacuum on-load tap changer;

[0093] S300: Determine an actual action sequence of the vacuum on-load tap changer in response to the test action sequence according to the voltage curve acquired by the voltage sensor and the current curve acquired by the current sensor.

[0094] Specifically, if Figure 2 As shown, the vacuum on-load tap changer includes a switch module and a tap selector. In response to the action of the tap selector, the switch module is actuated and the operating voltage of the on-load transformer is adjusted step by step.

[0095] The switch module includes an even-side transition circuit, an odd-side transition circuit, an even-side switching contact, an odd-side switching contact, an even-side main contact, and an odd-side main contact;

[0096] The even-number side transition circuit includes a first vacuum tube and a second vacuum tube, and the odd-number side transition circuit includes a third vacuum tube and a fourth vacuum tube;

[0097] Correspondingly, the test action sequence includes theoretical opening and closing actions for the even-numbered main contacts, the odd-numbered main contacts, the even-numbered switching contacts, the odd-numbered switching contacts and / or each vacuum tube.

[0098] Specifically, if Figure 2 As shown, the vacuum on-load tap changer is preset with a voltage sensor and a current sensor, including:

[0099] A current sensor provided in the even-side transition circuit is used to obtain a current curve flowing through the first vacuum tube or the second vacuum tube;

[0100] A current sensor provided in the odd-side transition circuit, for obtaining a current curve flowing through the third vacuum tube or the fourth vacuum tube;

[0101] A voltage sensor provided in the even-side transition circuit is used to obtain a voltage curve across the second vacuum tube;

[0102] The voltage sensor provided in the odd-side transition circuit is used to obtain the voltage curve across the third vacuum tube.

[0103] Specifically, if Figure 3、 Figure 4 and Figure 19 As shown, the test action sequence is used to switch from connecting an even-numbered tap via an even-side transition circuit to connecting an adjacent odd-numbered tap via an odd-side transition circuit; or

[0104] The test action sequence is used to switch from connecting an odd-numbered tap via an odd-side transition circuit to connecting an adjacent even-numbered tap via an even-side transition circuit;

[0105] When the even-numbered tap is connected via the even-numbered transition circuit, the states of the switch module include: the even-numbered main contact is closed, the even-numbered transfer contact is closed; the first vacuum tube is closed, the second vacuum tube is closed; the odd-numbered main contact is open, the odd-numbered transfer contact is open; the third vacuum tube is open, the fourth vacuum tube is open;

[0106] Among them, when the odd-numbered tap is connected through the odd-numbered side transition circuit, the status of the switching switch module includes: the odd-numbered side main contact is closed, the odd-numbered side conversion contact is closed; the third vacuum tube is closed, the fourth vacuum tube is closed; the even-numbered side main contact is open, the even-numbered side conversion contact is open; the first vacuum tube is open, and the second vacuum tube is open.

[0107] Specifically, if Figure 3 and Figure 4 As shown, determining the actual action sequence of the vacuum on-load tap changer in response to the test action sequence based on the voltage curve obtained by the voltage sensor and the current curve obtained by the current sensor includes:

[0108] like Figure 5 and Figure 6 As shown, according to the obtained current curve flowing through the first vacuum tube, the actual breaking action moment of the main contact on the even number side or the failure of the main contact on the even number side to perform the breaking action is determined;

[0109] like Figure 7 and Figure 8 As shown, according to the obtained voltage curve across the third vacuum tube, the actual closing action moment of the odd-side switching contact or the failure of the odd-side switching contact to perform the closing action is determined;

[0110] like Figure 9 and Figure 10 As shown, the actual breaking action moment of the first vacuum tube is determined according to the obtained current curve flowing through the second vacuum tube;

[0111] like Figure 11 and Figure 12 As shown, according to the obtained current curve flowing through the third vacuum tube, the actual closing action moment of the third vacuum tube is determined;

[0112] like Figure 13 and Figure 14 As shown, according to the obtained voltage curve across the second vacuum tube, the actual breaking action moment of the second vacuum tube is determined;

[0113] like Figure 15 and Figure 16 As shown, according to the obtained current curve flowing through the fourth vacuum tube, the actual closing action time of the fourth vacuum tube is determined;

[0114] like Figure 17 and Figure 18 As shown, according to the voltage curve obtained at both ends of the second vacuum tube, the actual breaking action moment of the even-numbered side switching contact or the failure of the even-numbered side switching contact to perform the breaking action is determined;

[0115] like Figure 19 and Figure 20 As shown, the actual closing action moment of the odd-side main contact is determined based on the obtained current curves flowing through the first vacuum tube, the second vacuum tube, the third vacuum tube, and the fourth vacuum tube.

[0116] In some embodiments, it further includes:

[0117] Based on the theoretical action times recorded in the test action sequence and the determined actual opening and closing action times, determine any one or more of the following:

[0118] Whether the even-side changeover contact, odd-side changeover contact, even-side main contact or odd-side main contact operates correctly at the set time;

[0119] Check whether the changeover contacts on the even side, the changeover contacts on the odd side, the main contacts on the even side or the main contacts on the odd side operate correctly after a delay.

[0120] In some embodiments, the vacuum on-load tap changer further comprises: a driving mechanism;

[0121] Based on the theoretical action times recorded in the test action sequence and the determined actual opening and closing action times, determine any one or more of the following:

[0122] The driving mechanism is stuck;

[0123] The driving mechanism slides;

[0124] The drive mechanism refuses to move.

[0125] like Figure 2 As shown, the first voltage sensor is provided in the transition resistance branch in the even-side transition circuit, and is used to obtain the voltage curve across the second vacuum tube K2 in the transition resistance branch;

[0126] The second voltage sensor is provided in the transition resistance branch in the odd-side transition circuit, and is used to obtain a voltage curve across the third vacuum tube K3 in the transition resistance branch;

[0127] Two first current sensors are respectively provided in the transition resistance branch and the transition branch in the even-side transition circuit, for obtaining the current curve flowing through the two ends of the second vacuum tube K2 in the transition resistance branch and the current curve flowing through the two ends of the first vacuum tube K1 in the transition branch;

[0128] Two second current sensors are provided in the transition resistance branch and the transition branch in the odd-side transition circuit, and are used to obtain the current curve flowing through the two ends of the third vacuum tube K3 in the transition resistance branch and the current curve flowing through the two ends of the fourth vacuum tube K4 in the transition branch.

[0129] Compared with setting up two additional voltage sensors on the first vacuum tube or the fourth vacuum tube, the scheme of setting up the above six sensors can show rich and sufficient transient characteristics. The information richness that can be obtained using these current or voltage curves is sufficient, the scheme is simpler, and the utilization efficiency of the equipment is higher.

[0130] In this way, the above voltage measurement points or current measurement points are symmetrical about the center point of the transformer, which is similar to the even-side transition circuit and the odd-side transition circuit being two symmetrical parts in a 2+2 structure in terms of function and structure.

[0131] Specifically, the voltage sensor is differentially connected across the switching contact (such as J1 or J2) and the vacuum tube (such as K2 or K3) in the transition resistor branch. This ensures that one end of the voltage sensor is at the same potential as the side of the vacuum tube away from the switching contact, while the other end is at the same potential as the side of the vacuum tube closer to the switching contact. The voltage sensor and vacuum tube are connected in parallel. This differential connection eliminates common-mode noise, such as ground noise and electromagnetic interference, ensuring signal integrity. The voltage sensor monitors a frequency range of 0-60kHz and a voltage range of ±4000V, which corresponds to the transformer's maximum step voltage of 4000V and provides a safety margin.

[0132] Specifically, the current sensors are respectively arranged in the transition resistance branch and the transition branch, and are connected in series with the vacuum tube; the monitoring frequency range of the current sensor includes: 0-200kHz, and the current monitoring range of the current sensor includes: ±1000A, which is compatible with the rated capacity of the transformer 1500kVA and has a safety margin.

[0133] The following characteristic index I K1 Indicates the current flowing through the first vacuum tube K1, using the characteristic index I K2 Indicates the current flowing through the second vacuum tube K2, using the characteristic index I K3Indicates the current flowing through the third vacuum tube K3, using the characteristic index I K4 Indicates the current flowing through the fourth vacuum tube K4. Using characteristic index U K2 Indicates the voltage across the second vacuum tube K2, using characteristic index U K3 Indicates the voltage across the third vacuum tube K3.

[0134] The following Figure 2 As an example, refer to the vacuum on-load tap-changer shown in Figure 4 、 Figure 5 、 Figure 7 、 Figure 9 、 Figure 11 、 Figure 13 、 Figure 15 、 Figure 17 and Figure 19 , illustrating the online monitoring method for the actual action sequence of the vacuum on-load tap-changer provided by an embodiment of the present invention.

[0135] Figure 4 、 Figure 5 、 Figure 7 、 Figure 9 、 Figure 11 、 Figure 13 、 Figure 15 、 Figure 17 and Figure 19 The following diagram sequentially illustrates a complete, decomposed switching process performed by the diverter switch module of the vacuum on-load tap changer in response to the test action sequence. Specifically, the tap selector switches from an even-numbered tap point to an odd-numbered tap point, and the diverter switch module switches from connection with tap 6 to connection with tap 7. It should be understood that the switching process of the tap selector from an even-numbered tap point to an odd-numbered tap point and the switching process from an odd-numbered tap point to an even-numbered tap point are theoretically completely symmetrical. Therefore, the voltage or current characteristics at the corresponding positions are also symmetrical and can be derived similarly, so this description will not be repeated.

[0136] When the switch module switches from being connected to tap 6 to being connected to tap 7, the drive mechanism drives the main contact A, main contact B, transfer contact J1, transfer contact J2, vacuum tubes K1, K2, K3, K4, etc. to perform opening or closing actions in accordance with the preset test action timing.

[0137] like Figure 2 、 Figure 4 and Figure 19As shown, before executing the test action sequence, that is, before the start of tap switching, the state is the steady state after the previous tap switching, or the initial state before the start of the current tap switching. At this time, the switch module connects tap 6 to the transformer neutral point; tap 7 is not connected. Specifically, main contact A is closed, transfer contact J1 is closed, one end of main contact A is connected to the even-numbered tap 6, and the other end of main contact A is connected to the transformer neutral point. The current is essentially zero; the closed first vacuum tube K1 and the closed second vacuum tube K2 are in a high-resistance state, and the current in the branch is essentially zero; the voltage across the closed second vacuum tube K2 is essentially zero, such as approximately equal to 0. The first vacuum tube K1 and the second vacuum tube K2 are connected to the transformer neutral point via transfer contact J1. The main contact B is opened, the change-over contact J2 is opened, the main contact B is disconnected from the tap 7, the change-over contact J2 is disconnected from the neutral point of the transformer, and the through-current is substantially zero; the third vacuum tube K3 is opened, the fourth vacuum tube K4 is opened, and the through-current in the branch is substantially zero; the voltage across the disconnected third vacuum tube K3 is substantially zero, such as approximately equal to 0. The coil voltage is the step voltage U step , basically zero.

[0138] Specifically, ignoring the impedance of the main contact A, vacuum tube K1, and vacuum tube K2, as shown in FIG. Figure 6 As shown, the current obtained and recorded by the two first current sensors I K1 and I K2 is approximately zero, such as I K1 is approximately equal to 0, I K2 =0. Figure 8 As shown by the purple line, the voltage U obtained and recorded by the first voltage sensor K2 Approximately zero, such as U K2 = 0. Ignore the circuit drift or temperature drift of the main contact B, vacuum tube K3, vacuum tube K4 and sensor, such as Figure 6 As shown, the current obtained and recorded by the two second current sensors I K3 and I K4 is approximately zero, such as I K3 =0, I K4 =0. Figure 8 As shown by the blue line, the voltage U obtained and recorded by the second voltage sensor K3 Approximately zero, such as U K3 = 0. Before the switching starts, in the initial state before the current switching tap starts, the values of the characteristic indicators are used as the initial current values or initial voltage values described later.

[0139] Referring to the above description, the transition resistance branch in the even-numbered side transition circuit is symmetrically arranged with the transition resistance branch in the odd-numbered side transition circuit, and they share the load current I through bridging during transition or switching taps. n The transition resistor R is used to limit the size of the current loop formed after the two taps are bridged for a short time.

[0140] Figure 3 Shown for Figure 2 The test action timing sequence shown is designed for the performance test of the vacuum on-load tap-changer, wherein the closing of each contact or vacuum tube is displayed as a high level, the opening is displayed as a low level, the switching from opening to closing is displayed as a rising edge pulse, and the switching from closing to opening is displayed as a falling edge pulse.

[0141] according to Figure 3 In the test action sequence shown, the process of switching from the even-numbered tap 6 to the odd-numbered tap 7 can be divided into the following steps S11 to S18.

[0142] Step S11: In accordance with the preset test action sequence, control the main contact A to open at the theoretical opening time TT A Break; monitor the current flowing through the first vacuum tube K1 to determine the actual breaking action time T of the main contact A A ;

[0143] like Figure 5 and Figure 6 As shown, the main contact A is open, and the first vacuum tube K1 is flowing (when the main contact A is open, K1 carries current). One end of the first vacuum tube K1 is connected to the even-numbered tap 6, and the other end of the first vacuum tube K1 is connected to the change-over contact J1 and then to the neutral point of the transformer. In this way, the current carrying capacity of the first vacuum tube K1, that is, the characteristic index I K1 From nothing to something.

[0144] Specifically, the breaking action time T of the main contact A is determined according to the change rate of the current flowing through the first vacuum tube K1 and / or the current flowing through the first vacuum tube K1. A .

[0145] Specifically, the moment when the change rate of the current flowing through the first vacuum tube K1 is greater than a preset change rate threshold (such as 5% to 10%) is determined as the opening action moment of the main contact A. A and / or

[0146] Specifically, the moment when the current flowing through the first vacuum tube K1 is greater than a preset current threshold (such as 5% to 10% of the maximum rated through current 600A) is determined as the breaking action moment T of the main contact A. A .

[0147] Specifically, the change rate of the current flowing through the first vacuum tube K1 is defined as: the real-time current IK1 The quotient of the absolute value of the difference from the initial current value and the acquired real-time current or the initial current value.

[0148] In one embodiment of the present invention, the current curve I flowing through the first vacuum tube K1 is obtained and recorded by an oscilloscope. K1 like Figure 6 As shown, Figure 6 The vertical line segment shows the actual breaking action time T of the main contact A. A .

[0149] Furthermore, the theoretical breaking time TT of the main contact A is compared A The actual breaking action time T A The deviation between them can determine the delay of the main contact A in performing the breaking action or determine that the main contact A does not perform the breaking action.

[0150] Step S12: In accordance with the preset test action sequence, control the switching contact J2 to close at the theoretical closing time TT J2 Close; monitor the voltage U across the third vacuum tube K3 K3 , determine the actual closing action time T of the switching contact J2 J2 ;

[0151] like Figure 7 and Figure 8 As shown, after the transfer contact J2 is closed, it is connected to the transfer contact J1, and the transfer contact J2 is connected to the neutral point of the transformer. The third vacuum tube K3 and the fourth vacuum tube K4 are connected to the multi-turn coil through the odd tap 7 respectively. The voltage across the coil is the step voltage, which is recorded as U step In this way, the potential difference or voltage across the third vacuum tube K3 provided in the transition resistance branch increases rapidly from zero to a certain value, for example, from a virtual voltage to a relatively large voltage.

[0152] Specifically, the closing action time T of the switching contact J2 is determined according to the voltage across the third vacuum tube K3 and / or the voltage change rate across the third vacuum tube K3. J2 .

[0153] Specifically, the moment when the voltage across the third vacuum tube K3 is greater than a preset voltage threshold (eg, 5% to 10% of the maximum voltage 4000V) is determined as the closing action moment T of the switching contact J2. J2 and / or

[0154] Specifically, the moment when the rate of change of the voltage across the third vacuum tube K3 is greater than a preset rate of change threshold (eg, 5% to 10%) is determined as the closing action moment T of the switching contact J2. J2 .

[0155] Specifically, the change rate of the voltage across the third vacuum tube K3 is defined as: the real-time voltage UK3 The quotient of the absolute value of the difference from the initial voltage value and the acquired real-time voltage or the initial voltage value.

[0156] In one embodiment of the present invention, the voltage curve U across the third vacuum tube K3 is obtained and recorded using an oscilloscope. K3 like Figure 8 As shown by the blue line, Figure 8 The actual closing action time T of the switching contact J2 is shown by a vertical line segment. J2 .

[0157] Furthermore, the theoretical closing time TT of the switching contact J2 is compared with J2 The actual closing action time T J2 The deviation between the switching contact J2 and the switching contact J2 can determine the delay in performing the closing action or determine that the switching contact J2 does not perform the closing action.

[0158] Step S13: In accordance with the preset test action sequence, control the first vacuum tube K1 to open at the theoretical opening time TT K1 Break; monitor the current I flowing through the second vacuum tube K2 K2 Determine the actual breaking action time T of the first vacuum tube K1 K1 .

[0159] Specifically, if Figure 9 As shown, at the moment when the first vacuum tube K1 is broken, the second vacuum tube K2 is flowing (K2 carries current when K1 is broken). After the first vacuum tube K1 performs the breaking action, the current I flowing through the second vacuum tube K2 K2 One end of the second vacuum tube K2 is connected to the even tap 6 via the resistor R, and the other end of the second vacuum tube K2 is connected to the switching contact J1 and further to the neutral point of the transformer.

[0160] Specifically, according to the current I flowing through the second vacuum tube K2 K2 The rate of change of is greater than the preset rate of change threshold and combined with the current I flowing through the second vacuum tube K2 K2 is greater than the preset current threshold, and the breaking action time T of the first vacuum tube K1 is determined. K1 .

[0161] Specifically, determine the current I flowing through the second vacuum tube K2 K2 The moment when the rate of change of is greater than a preset rate of change threshold (such as 5% to 10%) is the breaking action moment of the first vacuum tube K1. K1 and / or

[0162] Specifically, determine the current I flowing through the second vacuum tube K2 K2 The moment when the current is greater than a preset current threshold (such as 5% to 10% of the maximum rated through current 600A) is the breaking action moment of the first vacuum tube K1.K1 .

[0163] Specifically, the current I flowing through the second vacuum tube K2 K2 The rate of change is defined as: the real-time current I K2 The quotient of the absolute value of the difference from the initial current value and the acquired real-time current or the initial current value.

[0164] In one embodiment of the present invention, the current curve I flowing through the second vacuum tube K2 is K2 like Figure 10 As shown, Figure 10 The vertical line segment shows the actual breaking action time T of the first vacuum tube K1 K1 .

[0165] Furthermore, the theoretical breaking time TT of the first vacuum tube K1 is compared with K1 The actual breaking action time T K1 The deviation between them can determine the delay of the first vacuum tube K1 in performing the breaking action.

[0166] Step S14: In accordance with the preset test action sequence, control the third vacuum tube K3 to close at the theoretical closing time TT K3 Closed; according to the monitored current I flowing through the third vacuum tube K3 K3 , determine the closing action time T of the third vacuum tube K3 K3 .

[0167] Specifically, the third vacuum tube K3 is closed, and the current I flowing through the third vacuum tube K3 is K3 From nothing to something.

[0168] like Figure 11 As shown, at the moment when the third vacuum tube K3 closes, the third vacuum tube K3 passes current (when K3 is closed, K2 and K3 are bridged), one end of the third vacuum tube K3 is connected to the odd tap 7 through the resistor R, and the other end of the third vacuum tube K3 is connected to the switching contact J2 and then to the neutral point of the transformer. Figure 11 And such as Figure 12 As shown, the transition resistance branch in the even-numbered side transition circuit and the transition resistance branch in the odd-numbered side transition circuit jointly bear the load current I through bridging. n .

[0169] Specifically, according to the current I flowing through the third vacuum tube K3 K3 The rate of change of is greater than the preset rate of change threshold and combined with the current I flowing through the third vacuum tube K3 K3 is greater than the preset current threshold, and the actual closing action time T of the third vacuum tube K3 is determined. K3 .

[0170] Specifically, determine the current I flowing through the third vacuum tube K3K3 The moment when the rate of change of is greater than a preset rate of change threshold (such as 5% to 10%) is the actual closing action moment of the third vacuum tube K3. K3 and / or

[0171] Specifically, determine the current I flowing through the third vacuum tube K3 K3 The moment when the current is greater than a preset current threshold (such as 5% to 10% of the maximum rated through current 600A) is the closing action moment of the third vacuum tube K3. K3 .

[0172] Specifically, the change rate of the current flowing through the third vacuum tube K3 is defined as: the real-time current I K3 The absolute value of the difference between the initial current value and the real-time current I K3 Or the quotient of the initial value of the current.

[0173] In one embodiment of the present invention, the closing action time T of the current flowing through the third vacuum tube K3 is K3 like Figure 12 As shown, Figure 12 The vertical line segment shows the actual closing action time T of the third vacuum tube K3 K3 .

[0174] Furthermore, the theoretical breaking time TT of the third vacuum tube K3 is compared with K3 The actual closing action time T K3 The deviation between them can determine the delay of the third vacuum tube K3 in performing the breaking action.

[0175] Step S15: In accordance with the preset test action sequence, at the theoretical breaking time TT K2 Control the second vacuum tube K2 to be disconnected; according to the monitored voltage U across the second vacuum tube K2 K2 , determine the actual breaking action time T of the second vacuum tube K2 K2 .

[0176] Specifically, if Figure 14 As shown, at the moment when the second vacuum tube K2 is disconnected, the third vacuum tube K3 is open (as shown in FIG. Figure 14 As shown by the vertical horizontal line, after the bridge is disconnected, K2 is disconnected and K3 carries the current alone. The tap switching transition process ends, and the transition resistance branch in the even-side transition circuit is disconnected from the neutral point. The transition resistance branch in the even-side transition circuit is no longer bridged with the transition resistance branch in the odd-side transition circuit, and no longer shares the load current I n Since the second vacuum tube K2 is cut off and disconnected from the tap point or neutral point, the voltage U across the second vacuum tube K2 is K2 mutation.

[0177] Specifically, if Figure 13As shown, one end of the second vacuum tube K2 is disconnected from the even tap 6. At this point, the even tap 6 is disconnected from the transformer neutral point; the odd tap 7 is connected to the transformer neutral point via the third vacuum tube K3 and the changeover contact J2.

[0178] Specifically, according to the voltage U across the second vacuum tube K2 K2 The rate of change is greater than the preset rate of change threshold and combined with the voltage U across the second vacuum tube K2 K2 is greater than the preset voltage threshold, and the actual breaking action time T of the second vacuum tube K2 is determined. K2 .

[0179] Specifically, determine the voltage U across the second vacuum tube K2 K2 The moment when the change rate of is greater than the preset change rate threshold (such as 5% to 10%) is the breaking action moment of the second vacuum tube K2. K2 and / or

[0180] Specifically, determine the voltage U across the second vacuum tube K2 K2 The moment when the voltage is greater than a preset voltage threshold (such as 5% to 10% of the maximum voltage 4000V) is the breaking action moment of the second vacuum tube K2. K2 .

[0181] In one embodiment of the present invention, the voltage U across the second vacuum tube K2 is K2 Curves such as Figure 14 As shown, Figure 14 The vertical line segment shows the actual breaking action time T of the second vacuum tube K2 K2 .

[0182] Furthermore, the theoretical breaking time TT of the second vacuum tube K2 is compared with K2 The actual breaking action time T K2 The deviation between them can determine the delay of the second vacuum tube K2 in performing the breaking action.

[0183] Step S16: In accordance with the preset test action sequence, control the fourth vacuum tube K4 to be on at the theoretical time TT K4 Closed; according to the monitored current I flowing through the fourth vacuum tube K4 K4 , determine the actual closing action time T of the fourth vacuum tube K4 .

[0184] Specifically, if Figure 15 and Figure 16As shown, at the moment the fourth vacuum tube K4 closes, current flows through the fourth vacuum tube K4 (K4 is closed, K4 carries current alone). One end of the fourth vacuum tube K4 is connected to the odd tap 7 via the resistor R, and the other end of the fourth vacuum tube K4 is connected to the switching contact J2 and then to the neutral point of the transformer. The transient response of the transition circuit is reflected by the characteristic index I K4 From nothing to something.

[0185] Specifically, according to the current I flowing through the fourth vacuum tube K4 K4 The rate of change of is greater than the preset rate of change threshold and combined with the current I flowing through the fourth vacuum tube K4 K4 is greater than the preset current threshold, and the actual closing action time T of the fourth vacuum tube K4 is determined. K4 .

[0186] Specifically, determine the current I flowing through the fourth vacuum tube K4 K4 The moment when the rate of change of is greater than a preset rate of change threshold (such as 5% to 10%) is the actual closing action moment of the fourth vacuum tube K4. K4 and / or

[0187] Specifically, determine the current I flowing through the fourth vacuum tube K4 K4 The moment when the current is greater than a preset current threshold (such as 5% to 10% of the maximum rated through current 600A) is the closing action moment of the fourth vacuum tube K4. K4 .

[0188] Specifically, the change rate of the current flowing through the fourth vacuum tube K4 is defined as: the real-time current I K4 The absolute value of the difference between the initial current value and the real-time current I K4 Or the quotient of the initial value of the current.

[0189] In this way, the current I flowing through the fourth vacuum tube K4 can be K4 The rate of change of the current I K4 The amplitude of the rising stage determines the actual closing action time T of the fourth vacuum tube K4 K4 .

[0190] In one embodiment of the present invention, the current curve flowing through the fourth vacuum tube K4 is as follows: Figure 16 As shown, Figure 16 The vertical line segment shows the actual closing action time T of the fourth vacuum tube K4 K4 .

[0191] Furthermore, the theoretical closing action time TT of the fourth vacuum tube K4 is compared with K4 The actual breaking action time T K4 The deviation between them can determine the delay of the fourth vacuum tube K4 in performing the closing action.

[0192] Step S17: In accordance with the preset test action sequence, control the switching contact J1 at the theoretical time TT J1 According to the voltage U across the second vacuum tube K2 monitored K2 , determine the actual breaking action time T of the transfer contact J1 J1 .

[0193] like Figure 17 and Figure 18 As shown, after the even-side switching contact J1 is disconnected, the voltage U K2 From real voltage to imaginary voltage.

[0194] According to the voltage U across the second vacuum tube K2 K2 , the action moment of contact J1 can be determined. Specifically, the transient response is reflected in the characteristic index U K2 Rapid decrease, which can be determined by the voltage change rate combined with the voltage U K2 Less than the threshold value.

[0195] Specifically, determine the voltage U across the second vacuum tube K2 K2 The moment when the rate of change of is greater than the preset rate of change threshold (such as 5% to 10%) is the moment when the switching contact J1 opens. J1 and / or

[0196] Specifically, determine the voltage U across the second vacuum tube K2 K2 The moment when the voltage is less than the preset voltage threshold (such as 60% to 70% of the maximum voltage 4000V) is the moment when the switching contact J1 opens. J1 .

[0197] In one embodiment of the present invention, the voltage U across the second vacuum tube K2 is K2 Curves such as Figure 18 As shown, Figure 18 The vertical line segment shows the switching contact J1 opening action time T J1 .

[0198] Furthermore, the theoretical breaking time TT of the switching contact J1 is compared J1 The actual breaking action time T J1 The deviation between the switching contact J1 and the switching contact J1 can be used to determine the delay in performing the breaking action or to determine that the switching contact J1 does not perform the breaking action.

[0199] Step S18: In accordance with the preset test action sequence, the driving mechanism drives the odd-numbered side main contact B to the theoretical time TT B closure.

[0200] like Figure 19 As shown, after the odd-numbered main contact B is closed, it is connected to the transformer winding tap 7. The step voltage corresponding to the tap 7 is Ustep The main contact B is controlled to close and the switching process is completed. The transient response is reflected in the characteristic index I K1 =0,I K2 =0,I K3 =0,I K4 Approximately equal to 0.

[0201] Specifically, according to the current I flowing through the fourth vacuum tube K4 K4 The rate of change of is greater than the preset rate of change threshold and combined with the current I flowing through the fourth vacuum tube K4 K4 is greater than the preset current threshold, and the actual closing action time T of the main contact B is determined. B .

[0202] Specifically, determine the current I flowing through the fourth vacuum tube K4 K4 The moment when the rate of change of is greater than the preset rate of change threshold (such as 70% to 80%) is the actual closing action moment of the main contact B T B and / or

[0203] Specifically, determine the current I flowing through the fourth vacuum tube K4 K4 The moment when the current is less than the preset current threshold (such as 35% to 45% of the maximum rated through current 600A) is the actual closing action moment of the main contact B T B .

[0204] Specifically, the change rate of the current flowing through the fourth vacuum tube K4 is defined as: the real-time current I K4 The absolute value of the difference between the initial current value and the real-time current I K4 Or the quotient of the initial value of the current.

[0205] In this way, the current I flowing through the fourth vacuum tube K4 can be K4 The rate of change of the current I K4 The amplitude of the descending stage determines the actual closing action time T of the main contact B B .

[0206] In one embodiment of the present invention, the current curve flowing through the fourth vacuum tube K4 is as follows: Figure 20 As shown, Figure 20 The vertical line segment shows the actual closing action time T of the main contact B B .

[0207] Furthermore, the theoretical closing action time TT of the main contact B is compared B The actual closing action time T B The deviation between the two can determine the delay in the closing action of the main contact B or determine that the main contact B does not perform the closing action.

[0208] The above steps S11 to S18 can be simply recorded as follows:

[0209] like Figure 4 As shown in the figure, before the tap is switched, the transfer contact J1 is closed, the main contact A is flowing, and the current flowing through the vacuum tube K1 is approximately zero, which is recorded as I K1 is approximately equal to 0; the current flowing through the vacuum tube K2 is monitored to be zero, recorded as I K2 =0; the voltage U across the vacuum tube K2 is monitored K2 is zero, denoted as U K2 =0; the current flowing through the vacuum tube K3 is detected to be zero, recorded as I K3 =0; the voltage U across the vacuum tube K3 is monitored K3 is zero, denoted as U K3 =0; the circuit is in the open circuit state. The current flowing through the vacuum tube K4 is zero, which is recorded as I K4 =0; the circuit is in open circuit state.

[0210] like Figure 3 and Figure 5 As shown, 50ms after the test sequence starts, that is, the theoretical action time TT A , control the main contact A of the switch module to open. Figure 6 As shown, the breaking action moment of the main contact A is determined according to the current flowing through the vacuum tube K1; the transient response is reflected in the characteristic index I K1 From nothing to something, such as the current change rate combined with the current I flowing through the vacuum tube K1 K1 If the current is greater than the preset threshold, the opening action moment of the main contact A is determined. The current change rate can be determined based on the difference between the current values of two adjacent sampling points.

[0211] The transient response can also be reflected as the current I flowing through the first vacuum tube K1 K1 is greater than a preset threshold, such as determining that the current I flowing through the vacuum tube K1 K1 The moment when the load current rises from zero to 5% is the action moment of main contact A.

[0212] like Figure 3 and Figure 7 As shown, 55ms after the test sequence starts, which is the theoretical action time TT J2 , controlling the switching contact J2 of the switching module to close. Figure 8 As shown, the action time T of the switching contact J2 is determined according to the voltage across the third vacuum tube K3. J2 The transient response is reflected in the characteristic index U K3 Increase, can be obtained by the voltage change rate of the vacuum tube K3 and the voltage U across the vacuum tube K3 K3When the voltage is greater than a threshold (e.g., 1% of the step voltage), the switching contact J2 closes. The voltage change rate can be determined based on the voltage difference between two adjacent sampling points. For example, the contact actuation moment can be determined when the voltage across vacuum tube K3 rises from zero to 1% of the step voltage.

[0213] like Figure 3 and Figure 9 As shown, 61ms after the test sequence starts, which is the theoretical action time TT K1 , controls the first vacuum tube K1 of the switching module to be disconnected. Figure 10 As shown, the breaking action moment of the first vacuum tube K1 is determined according to the current flowing through the second vacuum tube K2. The transient response is reflected in the characteristic index I K2 From nothing to something, the current change rate can be combined with the current I flowing through the second vacuum tube K2 K2 The current change rate can be determined based on the difference between the current values of two adjacent sampling points.

[0214] like Figure 3 and Figure 11 As shown, 77ms after the test sequence starts, which is the theoretical action time TT K3 , controls the third vacuum tube K3 of the switching module to be closed. Figure 12 As shown, the closing action time of the third vacuum tube K3 is determined according to the current flowing through the third vacuum tube K3. K3 From nothing to something, the current change rate can be combined with the current I flowing through the third vacuum tube K3 K3 The current change rate can be determined based on the difference between the current values of two adjacent sampling points.

[0215] like Figure 3 and Figure 13 As shown, 82ms after the test sequence starts, which is the theoretical action time TT K2 , control the switching module's second vacuum tube K2 to be disconnected. Figure 14 As shown, the moment of breaking action of the second vacuum tube K2 is determined according to the voltage across the second vacuum tube K2. The transient response is reflected in the characteristic index U K2 A sudden change occurs, which can be obtained by combining the voltage change rate of the second vacuum tube K2 with the voltage U across the second vacuum tube K2. K2 The voltage change rate can be determined based on the voltage difference between two adjacent sampling points.

[0216] like Figure 3 and Figure 15As shown, 97ms after the test sequence starts, which is the theoretical action time TT K4 , controls the fourth vacuum tube K4 of the switching module to be closed. Figure 16 As shown, the closing action time of the fourth vacuum tube K4 is determined according to the current flowing through the fourth vacuum tube K4. K4 From scratch, the current change rate flowing through the fourth vacuum tube K4 can be combined with the I flowing through the fourth vacuum tube K4. K4 The current change rate can be determined based on the difference between the current values of two adjacent sampling points.

[0217] like Figure 3 and Figure 17 As shown, 102ms after the test sequence starts, which is the theoretical action time TT J1 , control the switching contact J1 of the switch module to open. Figure 18 As shown, the contact action time is determined according to the voltage across the second vacuum tube K2. K2 Rapid decrease, which can be determined by the voltage change rate combined with the voltage U K2 Determined to be less than a threshold value (such as 1% of the level voltage).

[0218] like Figure 3 and Figure 19 As shown, 110ms after the test sequence starts, which is the theoretical action time TT B , controlling the main contact B of the switch module to close. Figure 20 As shown, close the main contact B to complete the switching process. If the transient response is reflected in the characteristic index I K4 Rapid decrease can be determined by the current change rate combined with the current I flowing through the fourth vacuum tube K4. K4 is less than a threshold value (such as 5% of the load current). After the switch is completed, I K1 =0,I K2 =0,I K3 =0,I K4 Approximately equal to 0; U K2 =0,U K3 =0.

[0219] Furthermore, the actual action sequence that responds to the test action sequence can be generated by utilizing the determined actual opening action moments and the actual closing action moments.

[0220] Furthermore, the actual action sequence is compared with the preset test action sequence to determine whether a certain contact or vacuum tube has an abnormality. For example, it is determined whether each contact is correctly operated at the set time point, that is, whether the above-mentioned action indicators (such as voltage or current values meeting the change rate or threshold) appear, which can indicate whether the contact is normal. For example, in step S12, it is detected that I k2 If it does not appear, it means that contact A has not been disconnected and is still in the closed state, which means that contact A is stuck, loose, or has other abnormalities and cannot be driven to operate.

[0221] Furthermore, if contact A operates correctly, but the time at which its operation indicator occurs deviates from the preset value by ±3ms, it indicates that the contact is loose.

[0222] Furthermore, the actual time intervals from T1, T2 to T5 calculated based on the actual action sequence are Figure 3 The time intervals T1, T2 to T5 shown exceed the design values. For example, if T3 exceeds 10ms, it means that the drive mechanism of the tap changer is stuck and cannot operate normally.

[0223] Furthermore, if the action indicators of each contact appear 2 times or more consecutively, it indicates that the driving mechanism of the tap changer has slipped.

[0224] Furthermore, if the action indicators of each contact do not appear, it indicates that the driving mechanism of the tap changer refuses to operate.

[0225] It should be understood that the relevant technical documents record the known types of defects corresponding to various types of timing anomalies or timing differences, which can be easily queried and determined, and will not be repeated here.

[0226] It should be understood that when implementing the method for online monitoring the actual operation sequence of a vacuum on-load tap-changer according to an embodiment of the present invention, the specific values or percentage ranges of the voltage change rate, power change rate, voltage threshold, or current threshold used at each actual operation moment can be flexibly adjusted according to the specific technical conditions of the vacuum on-load tap-changer, and no further details are given.

[0227] like Figure 21 As shown, the vacuum on-load tap-changer actual action sequence online monitoring device according to the embodiment of the present invention is used to execute the above-mentioned vacuum on-load tap-changer actual action sequence online monitoring method, including:

[0228] A control module is used to control the operation of the vacuum on-load tap-changer according to the test action sequence to gradually adjust the operating voltage of the on-load transformer; wherein the vacuum on-load tap-changer is preset with a voltage sensor and a current sensor;

[0229] a measuring module, configured to record a voltage curve obtained by a preset voltage sensor of the vacuum on-load tap changer, and a current curve obtained by a preset current sensor of the vacuum on-load tap changer;

[0230] The processing module is configured to determine an actual action sequence of the vacuum on-load tap changer in response to the test action sequence according to the voltage curve acquired by the voltage sensor and the current curve acquired by the current sensor.

[0231] The specific implementation methods and corresponding technical effects can be determined by referring to the above methods and will not be described in detail here.

[0232] The embodiment of the present invention provides an online monitoring system for the actual operation sequence of a vacuum on-load tap-changer. The online monitoring system is used to online monitor the transient response of the vacuum on-load tap-changer and online generate the operation sequence of the switch.

[0233] The online monitoring system includes: a signal processing unit, a signal acquisition unit, and a sensor unit. The sensor unit is arranged at the switching switch of the vacuum on-load tap changer; the signal processing unit processes the sensor data collected by the signal acquisition unit, generates the actual action sequence of the switching switch online, and analyzes whether the action sequence is abnormal.

[0234] Specifically, during the switching process, when the current in any transition resistance branch or transition branch is detected to be greater than a preset threshold, the active current is determined to be present, and the signal acquisition unit is activated to synchronously acquire data from the voltage and current sensors. The signal acquisition unit has a sampling accuracy of 16 bits and a sampling frequency of 1 MHz for each signal. The signal processing module is connected to the signal acquisition unit, acquires the voltage and current signals from the signal acquisition unit, and generates the actual action sequence.

[0235] In summary, the method and device for online monitoring the actual operation sequence of a vacuum on-load tapchanger provided by the embodiments of the present invention control the tapchanger's switching process according to its preset test operation sequence; obtain the voltage and current from the transient response of each transition resistance branch during the switching process; generate the actual operation sequence of the tapchanger based on the voltage and current in the obtained transient response; and determine key status information of the vacuum on-load tapchanger by comparing the preset test operation sequence with the actual operation sequence. This solves the problem of being unable to monitor the actual operation sequence of a vacuum on-load tapchanger during operation, allows direct access to key status information of the vacuum on-load tapchanger, and improves the ability to control the operating status.

[0236] The embodiment of the present invention also provides a terminal to execute the method. Figure 22 It shows a schematic diagram of a terminal proposed in some embodiments of the present invention. Figure 22As shown, the terminal 8 includes: a processor 800, a memory 801, a bus 802 and a communication interface 803, and the processor 800, the communication interface 803 and the memory 801 are connected via the bus 802; the memory 801 stores a computer program that can be run on the processor 800, and when the processor 800 runs the computer program, it executes the method proposed in any embodiment of the present invention.

[0237] Memory 801 may include high-speed random access memory (RAM) and may also include non-volatile memory, such as at least one disk drive. Communication between the device network element and at least one other network element is achieved via at least one communication interface 803 (which may be wired or wireless), and may utilize the Internet, a wide area network, a local area network, a metropolitan area network, or the like.

[0238] The bus 802 may be an ISA bus, a PCI bus, or an EISA bus. The bus may be divided into an address bus, a data bus, a control bus, etc. The memory 801 is used to store programs. The processor 800 executes the programs upon receiving execution instructions. The method disclosed in any implementation of the embodiment of the present invention may be applied to the processor 800 or implemented by the processor 800.

[0239] Processor 800 may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the method may be performed by hardware integrated logic circuits or software instructions within processor 800. Processor 800 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component. It may implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of the present invention. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in conjunction with the embodiments of the present invention may be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software modules within the decoding processor. The software modules may be located in storage media well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or the like. The storage medium is located in the memory 801 , and the processor 800 reads the information in the memory 801 and completes the steps of the method in combination with its hardware.

[0240] The terminal proposed in the embodiment of the present invention and the method in the embodiment of the present invention are based on the same inventive concept and have the same beneficial effects as the method adopted, operated or implemented by them.

[0241] like Figure 23 As shown, an embodiment of the present invention also provides a computer-readable storage medium corresponding to the method proposed in the aforementioned embodiment, and the computer-readable storage medium is a CD, on which a computer program (i.e., program product 900) is stored. When the computer program is run by a processor, it will execute the method proposed in any of the aforementioned embodiments.

[0242] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical or magnetic storage media, which are not listed here one by one.

[0243] The computer-readable storage medium proposed in the embodiment of the present invention and the method of the embodiment of the present invention are based on the same inventive concept and have the same beneficial effects as the method adopted, run or implemented by the application program stored therein.

[0244] It should be noted that, in the description of the present invention, the terms "up", "down", "left", "right", "inside", "outside" and the like indicating directions or positional relationships are the directions or positional relationships shown in the accompanying drawings. This is merely for the convenience of description and does not indicate or imply that the system or component must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0245] Furthermore, it should be noted that, in the description of the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediary, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0246] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer, characterized in that: include: According to the test action sequence, the vacuum on-load tap changer is controlled to operate so as to gradually adjust the operating voltage of the on-load transformer; wherein the vacuum on-load tap changer is pre-set with a voltage sensor and a current sensor; the vacuum on-load tap changer includes a diverter switch module and a tap selector; in response to the operation of the tap selector, the diverter switch module operates and gradually adjusts the operating voltage of the on-load transformer; The switch module includes an even-side transition circuit, an odd-side transition circuit, an even-side switching contact, an odd-side switching contact, an even-side main contact, and an odd-side main contact; The even-number side transition circuit includes a first vacuum tube and a second vacuum tube, and the odd-number side transition circuit includes a third vacuum tube and a fourth vacuum tube; Recording a voltage curve obtained by a preset voltage sensor of the vacuum on-load tap changer, and recording a current curve obtained by a preset current sensor of the vacuum on-load tap changer; Determining an actual action sequence of the vacuum on-load tap changer in response to the test action sequence according to the voltage curve acquired by the voltage sensor and the current curve acquired by the current sensor includes: determining an actual breaking action time of the first vacuum tube according to the obtained current curve flowing through the second vacuum tube; determining an actual closing action time of the third vacuum tube according to the acquired current curve flowing through the third vacuum tube; determining an actual breaking action time of the second vacuum tube according to the obtained voltage curve across the second vacuum tube; The actual closing action time of the fourth vacuum tube is determined according to the acquired current curve flowing through the fourth vacuum tube.

2. The method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to claim 1, characterized in that: The test action sequence includes theoretical opening and closing actions for the even-side main contacts, the odd-side main contacts, the even-side switching contacts, the odd-side switching contacts and / or each vacuum tube.

3. The method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to claim 2, characterized in that: The vacuum on-load tap changer is provided with a preset voltage sensor and a current sensor, including: A current sensor provided in the even-side transition circuit is used to obtain a current curve flowing through the first vacuum tube or the second vacuum tube; A current sensor provided in the odd-side transition circuit, for obtaining a current curve flowing through the third vacuum tube or the fourth vacuum tube; A voltage sensor provided in the even-side transition circuit is used to obtain a voltage curve across the second vacuum tube; The voltage sensor provided in the odd-side transition circuit is used to obtain the voltage curve across the third vacuum tube.

4. The method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to claim 3, characterized in that: The test action sequence is used to switch from connecting an even-numbered tap via an even-side transition circuit to connecting an adjacent odd-numbered tap via an odd-side transition circuit; or The test action sequence is used to switch from connecting an odd-numbered tap via an odd-side transition circuit to connecting an adjacent even-numbered tap via an even-side transition circuit; When the even-numbered tap is connected via the even-numbered transition circuit, the states of the switch module include: the even-numbered main contact is closed, the even-numbered transfer contact is closed; the first vacuum tube is closed, the second vacuum tube is closed; the odd-numbered main contact is open, the odd-numbered transfer contact is open; the third vacuum tube is open, the fourth vacuum tube is open; Among them, when the odd-numbered tap is connected through the odd-numbered side transition circuit, the status of the switching switch module includes: the odd-numbered side main contact is closed, the odd-numbered side conversion contact is closed; the third vacuum tube is closed, the fourth vacuum tube is closed; the even-numbered side main contact is open, the even-numbered side conversion contact is open; the first vacuum tube is open, and the second vacuum tube is open.

5. The method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to claim 4, characterized in that: Determining an actual action sequence of the vacuum on-load tap changer in response to the test action sequence based on the voltage curve acquired by the voltage sensor and the current curve acquired by the current sensor, further comprising: determining, based on the acquired current curve flowing through the first vacuum tube, an actual breaking action moment of the main contact on the even number side or a failure of the main contact on the even number side to perform the breaking action; determining, based on the obtained voltage curve across the third vacuum tube, the actual closing action moment of the odd-numbered side switching contact or the failure of the odd-numbered side switching contact to perform the closing action; determining, based on the obtained voltage curve across the second vacuum tube, the actual breaking action moment of the even-numbered side switching contact or the failure of the even-numbered side switching contact to perform the breaking action; The actual closing action moment of the odd-side main contact is determined according to the obtained current curves flowing through the first vacuum tube, the second vacuum tube, the third vacuum tube, and the fourth vacuum tube.

6. The method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to claim 5, characterized in that: Also includes: Based on the theoretical action times recorded in the test action sequence and the determined actual opening and closing action times, determine any one or more of the following: Whether the even-side changeover contact, odd-side changeover contact, even-side main contact or odd-side main contact operates correctly at the set time; Check whether the changeover contacts on the even side, the changeover contacts on the odd side, the main contacts on the even side or the main contacts on the odd side operate correctly after a delay.

7. The method for online monitoring of the actual operation sequence of a vacuum on-load tap-changer according to claim 6, characterized in that: The vacuum on-load tap changer further comprises: a driving mechanism; Based on the theoretical action times recorded in the test action sequence and the determined actual opening and closing action times, determine any one or more of the following: The driving mechanism is stuck; The driving mechanism slides; The drive mechanism refuses to move.

8. An online monitoring device for the actual operation sequence of a vacuum on-load tap-changer, characterized in that: The method for online monitoring of the actual operation sequence of a vacuum on-load tap changer according to any one of claims 1 to 7 comprises: a control module, configured to control the operation of the vacuum on-load tap-changer according to a test operation sequence to gradually adjust the operating voltage of the on-load transformer; wherein the vacuum on-load tap-changer is pre-installed with a voltage sensor and a current sensor; the vacuum on-load tap-changer includes a diverter switch module and a tap selector; in response to the operation of the tap selector, the diverter switch module operates and gradually adjusts the operating voltage of the on-load transformer; The switch module includes an even-side transition circuit, an odd-side transition circuit, an even-side switching contact, an odd-side switching contact, an even-side main contact, and an odd-side main contact; The even-number side transition circuit includes a first vacuum tube and a second vacuum tube, and the odd-number side transition circuit includes a third vacuum tube and a fourth vacuum tube; a measuring module, configured to record a voltage curve obtained by a preset voltage sensor of the vacuum on-load tap changer, and a current curve obtained by a preset current sensor of the vacuum on-load tap changer; A processing module, configured to determine an actual action sequence of the vacuum on-load tap changer in response to the test action sequence based on the voltage curve obtained by the voltage sensor and the current curve obtained by the current sensor, comprising: determining an actual breaking action time of the first vacuum tube according to the obtained current curve flowing through the second vacuum tube; determining an actual closing action time of the third vacuum tube according to the acquired current curve flowing through the third vacuum tube; determining an actual breaking action time of the second vacuum tube according to the obtained voltage curve across the second vacuum tube; The actual closing action time of the fourth vacuum tube is determined according to the acquired current curve flowing through the fourth vacuum tube.

9. A terminal comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method for online monitoring of the actual operation sequence of a vacuum on-load tap changer according to any one of claims 1 to 7.

10. A computer storage medium, characterized in that Computer-executable instructions are stored, and the computer-executable instructions are used to execute the online monitoring method for the actual action sequence of the vacuum on-load tap changer according to any one of claims 1 to 7.

Images