A driving control method and device for a pressure relief valve of an on-load tap-changer oil chamber

Abstract

The present disclosure discloses a method for driving and controlling a pressure relief valve in an on-load tap changer oil chamber, comprising the following steps: obtaining a dynamic pressure signal, a static pressure signal, and a voltage and current signal within the on-load tap changer oil chamber; determining a pressure rise type within the oil chamber based on the obtained dynamic pressure signal and static pressure signal within the on-load tap changer oil chamber; determining an arc fault type within the oil chamber based on the obtained voltage and current signals within the on-load tap changer oil chamber; and controlling a pressure relief valve to perform corresponding actions based on the pressure rise type and the arc fault type.

Description

Technical Field

[0001] The present disclosure belongs to the field of explosion-proofing of electric power equipment, and particularly relates to a method and device for driving and controlling an oil chamber pressure relief valve of an on-load tap changer. Background Art

[0002] On-load tap changers (OLTCs) used in ultra-high voltage converter transformers frequently adjust voltage, making arc faults prone to occur during switching. This arcing process causes the transformer oil to decompose and vaporize, leading to increased oil pressure within the OLTC oil compartment. To prevent excessive internal pressure from damaging the container structure, a pressure relief valve is typically installed on top of the OLTC oil compartment. The pressure relief valve is a key component of the transformer's OLTC oil compartment, primarily controlling or limiting internal pressure. When the internal pressure of the OLTC oil compartment exceeds the set pressure, the pressure relief valve rapidly opens, releasing high-pressure fluid from the pressure relief valve outlet. This release of fluid significantly reduces the internal pressure, and once it reaches the shutoff pressure, the pressure relief valve automatically closes and resets. In summary, the pressure relief valve effectively addresses the problem of excessive internal pressure within the OLTC oil compartment, and its reliable operation is crucial to the safe operation of the transformer.

[0003] Based on the rate of pressure rise, the pressure rise within the OLTC oil chamber can be categorized as either a sudden surge or a subtle one. A sudden surge is often caused by high-current arcing, while a subtle one is often caused by thermal expansion of the fluid associated with increased temperature. A sudden surge typically indicates a serious fault in the electrical equipment, requiring prompt troubleshooting and pressure relief. A subtle pressure rise, however, indicates a temperature change or a controlled, minor discharge. However, the accumulation of a subtle pressure rise over a long period of time can trigger the pressure relief valve to trip. This prolonged accumulation of subtle pressure rises can cause the valve to trip, necessitating unnecessary power outages and maintenance, and is considered a misoperation of the pressure relief valve. Currently, power system agencies address this issue by adjusting the oil level and performing regular maintenance. However, this solution does not fundamentally address the issue and is labor-intensive.

[0004] In some cases, the pressure is released quickly, causing the pressure to drop to the closing pressure instantly, and the pressure relief valve closes quickly. However, the fault has not ended or the overpressure has not been completely released, so the pressure rises again. This process causes a short-term switching action of the pressure relief valve, also known as "frequency hopping". Frequency hopping of the pressure relief valve can easily damage the sealing surface and the mechanical structure of the pressure relief valve, greatly reducing the life and reliability of the pressure relief valve. At present, valve manufacturers usually solve the problem of frequency hopping of the pressure relief valve by adjusting the spring stiffness and setting the reset pressure. Users usually solve the problem by replacing the pressure relief valve with an appropriate throat diameter. However, both solutions are based on experience-based changes, and the changes sacrifice the pressure release efficiency. They cannot provide comprehensive protection against various arc fault pressures.

[0005] In summary, existing OLTC pressure relief valves are usually opened passively based on a pressure-sensing diaphragm. However, the passive opening method cannot identify the type of pressure increase, and the pressure relief valve itself does not have the active decision-making power to open and close. As a result, malfunctions such as malfunction and frequency hopping of the pressure relief valve often occur, seriously threatening the stability of substation operation. Summary of the Invention

[0006] In response to the deficiencies in the prior art, the present invention aims to provide a method for driving and controlling the pressure relief valve in the oil chamber of an on-load tap changer. The method distinguishes the types of pressure rise in the oil chamber and can issue reasonable instructions to the pressure relief valve according to different pressure rise types to selectively determine tripping.

[0007] To achieve the above objectives, the present disclosure provides the following technical solutions:

[0008] A method for driving and controlling an oil chamber pressure relief valve of an on-load tap changer, wherein the method comprises the following steps:

[0009] Obtain dynamic pressure signal, static pressure signal, voltage and current signal in the oil compartment of the on-load tap changer;

[0010] Determine the type of pressure rise in the oil chamber based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer;

[0011] Based on the acquired voltage and current signals in the oil compartment of the on-load tap changer, the type of arc fault in the oil compartment is determined;

[0012] The pressure relief valve is controlled to perform corresponding actions based on the pressure rise type and arc fault type.

[0013] Preferably, the determining the type of pressure rise in the oil chamber based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer comprises the following steps:

[0014] Integrate the collected dynamic and static pressure signals to obtain the pressure measurement value in the oil chamber;

[0015] Correct the pressure measurement value to obtain the actual pressure value;

[0016] Determine the type of pressure rise in the oil chamber based on the actual pressure value.

[0017] Preferably, obtaining the pressure measurement value in the oil chamber includes: integrating the obtained dynamic and static pressure signals.

[0018] Preferably, the step of determining the type of arc fault in the on-load tap changer oil compartment based on the acquired voltage and current signals in the oil compartment comprises the following steps:

[0019] Extract the time domain characteristics of voltage and current, and judge whether an arc fault occurs in the oil chamber based on the time domain characteristics;

[0020] The frequency domain characteristics of voltage and current are extracted, and the type of arc fault in the oil chamber is determined based on the frequency domain characteristics.

[0021] The present disclosure also provides a drive control device for an on-load tap changer oil chamber pressure relief valve, comprising:

[0022] Acquisition module, used to obtain dynamic pressure signal, static pressure signal, voltage and current signal in the oil chamber of the on-load tap changer;

[0023] a first judgment module, configured to judge a pressure rise type in the oil chamber based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer;

[0024] a second judgment module, configured to judge the type of arc fault in the oil compartment of the on-load tap changer based on the acquired voltage and current signals in the oil compartment;

[0025] The control module is used to control the pressure relief valve to perform corresponding actions based on the pressure rise type and the arc fault type.

[0026] Preferably, the device further comprises:

[0027] The calculation module is used to integrate the acquired dynamic pressure signal and static pressure signal to obtain the pressure measurement value in the oil chamber.

[0028] Preferably, the device further comprises:

[0029] The correction module is used to correct the pressure measurement value in the oil chamber to obtain the actual pressure value in the oil chamber.

[0030] Preferably, the device further comprises:

[0031] The first extraction module is used to extract the time domain characteristics of the voltage and current signals and determine whether an arc fault occurs in the oil chamber based on the time domain characteristics;

[0032] The second extraction module is used to extract the frequency domain characteristics of voltage and current, and determine the type of arc fault in the oil chamber according to the frequency domain characteristics.

[0033] The present disclosure also provides a readable storage medium, wherein the readable storage medium stores a program, and the program can be called by a processor to execute any of the above methods.

[0034] The present disclosure further provides an electronic device, wherein the electronic device includes:

[0035] Acquisition module, used to collect dynamic pressure signal, static pressure signal, voltage and current signal in the oil compartment of the on-load tap changer;

[0036] one or more processors;

[0037] a memory for storing one or more programs, wherein the programs are configured to be executed by the one or more processors, wherein the one or more programs are executed by the processors to perform any of the above methods to control the pressure relief valve to perform corresponding actions based on the dynamic pressure signal, static pressure signal, and voltage and current signals in the on-load tap changer oil compartment collected by the collection module.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] 1. The present invention distinguishes pressure rise types and can issue reasonable instructions to the pressure relief valve according to different pressure rise types to selectively determine tripping, effectively avoiding unnecessary losses caused by malfunctioning and tripping of traditional pressure relief valves;

[0040] 2. The present disclosure uses the static pressure signal as the basis for the reset instruction, thus avoiding the frequency hopping phenomenon of the pressure relief valve caused by excessively fast pressure release speed or pressure fluctuation;

[0041] 3. The present disclosure adopts a delayed reset strategy for the pressure relief valve, thereby preventing the pressure relief valve from frequently tripping while also allowing the pressure to be fully released. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a flow chart of a method for driving and controlling an oil chamber pressure relief valve of an on-load tap changer provided by one embodiment of the present disclosure;

[0043] Figure 2 is a flowchart of a pressure relief valve control process provided by another embodiment of the present disclosure;

[0044] Figure 3This is a spectrum diagram of an arc fault occurring in the oil compartment of an on-load tap changer provided by another embodiment of the present disclosure. DETAILED DESCRIPTION

[0045] The following will refer to the attached Figures 1 to 3 Specific embodiments of the present disclosure are described in detail. Although specific 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 described herein. Instead, 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.

[0046] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the present disclosure, but the description is based on the general principles of the specification and is not used to limit the scope of the present disclosure. The scope of protection of the present disclosure shall be as defined by the attached claims.

[0047] To facilitate understanding of the embodiments of the present disclosure, further explanation will be given below using specific embodiments as examples in conjunction with the accompanying drawings, and the accompanying drawings do not constitute a limitation on the embodiments of the present disclosure.

[0048] In one embodiment, Figure 1 As shown, the present disclosure provides a method for driving and controlling an oil chamber pressure relief valve of an on-load tap changer, wherein the method comprises the following steps:

[0049] Obtain dynamic pressure signal, static pressure signal, voltage and current signal in the oil compartment of the on-load tap changer;

[0050] Determining the type of pressure rise in the oil chamber based on the dynamic pressure signal and the static pressure signal in the oil chamber of the on-load tap changer obtained by the dynamic pressure sensor and the static pressure sensor;

[0051] Determining the type of arc fault in the on-load tap-changer oil compartment based on the acquired voltage and current signals in the oil compartment;

[0052] The pressure relief valve is controlled to perform corresponding actions based on the pressure rise type and arc fault type.

[0053] In another embodiment, the determining the type of pressure rise in the oil chamber based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer comprises the following steps:

[0054] Get the pressure measurement value in the oil chamber;

[0055] Correcting the pressure measurement value to obtain the actual pressure value;

[0056] Determine the type of pressure rise in the oil chamber based on the actual pressure value.

[0057] In another embodiment, obtaining the pressure measurement value in the oil chamber includes integrating the obtained dynamic and static pressure signals.

[0058] In another embodiment, determining the type of arc fault in the on-load tap changer oil compartment based on the acquired voltage and current signals in the oil compartment comprises the following steps:

[0059] Extract the time domain characteristics of voltage and current, and judge whether an arc fault occurs in the oil chamber based on the time domain characteristics;

[0060] The frequency domain characteristics of voltage and current are extracted, and the type of arc fault in the oil chamber is determined based on the frequency domain characteristics.

[0061] The above embodiments constitute the complete technical solution of the present disclosure. Figure 2The solution described in this disclosure is further described. First, a dynamic pressure sensor and a static pressure sensor are required to be arranged within the oil chamber. These two types of pressure sensors output dynamic and static pressure signals, respectively. The pressure signals are integrated to obtain the pressure measurement value within the oil chamber. It is important to understand that the measured value differs from the actual value. Therefore, the measured value needs to be corrected based on the sensor's transfer function to obtain the actual pressure value. When the actual pressure value within the oil chamber exceeds the opening pressure of the pressure relief valve, the pressure rise type is determined to be a sudden increase based on the actual pressure value. The specific determination process is as follows: Slow pressure changes are measured and output by the static pressure sensor. At this time, the signal output by the dynamic pressure sensor is very low after processing and can be ignored. Therefore, when a slow increase in static pressure occurs, the pressure rise type can be determined to be a slight pressure rise. Sudden pressure changes are measured and output by the dynamic pressure sensor. At this time, the signal output by the static pressure sensor remains almost unchanged after processing. Therefore, when a sudden increase in dynamic pressure occurs, it can be determined to be a sudden increase in pressure. If the pressure rise is determined to be a non-surge type, i.e., a static type, an opening command is sent to the pressure relief valve without tripping. During the pressure relief process, if the static pressure falls below the closing pressure of the pressure relief valve, the pressure relief valve resets. If the pressure rise is a surge type, an opening command is sent to the pressure relief valve while simultaneously receiving voltage and current signals. The time domain characteristics of these signals are extracted to determine whether an arc fault has occurred within the oil chamber. It should be noted that an arc fault within the oil chamber will cause fluctuations in voltage, current, or both, exhibiting typical step characteristics. Therefore, if a sudden change in the amplitude of the monitored voltage or current is detected (i.e., the first-order derivative of the voltage or current with respect to time changes compared to the voltage and current waveforms during normal operation. If the amplitude deviates from the normal operating amplitude, an arc fault can be considered to have occurred. The degree of amplitude change varies depending on the system), an arc fault can be determined within the oil chamber.

[0062] After determining that an arc fault has occurred in the oil chamber, the frequency domain characteristics of the voltage and current signals are continuously extracted to determine whether the arc fault is a continuous arc fault. Figure 3This is a current spectrum diagram of a sudden voltage rise caused by an arc fault in the oil compartment of an on-load tapchanger. The peak of this spectrum is around 17 kHz. If the frequency corresponding to the peak exceeds 17 kHz, the fault type is a continuous arc fault. In this case, the pressure relief valve trips and issues a risk warning to alert maintenance personnel of the safety hazard in the on-load tapchanger oil compartment. The pressure relief valve remains open. After pressure relief, if the static pressure falls below the closing pressure, a delayed reset is initiated. (The pressure typically drops to a safe value within hundreds of milliseconds, so this delayed reset time is usually set to a few seconds.) This effectively avoids the frequency jumps that occur when a traditional pressure relief valve resets due to pressure fluctuations or an ongoing fault. Conversely, if the frequency corresponding to the peak is less than 17 kHz, the fault type is a non-sustained arc fault. In this case, a risk warning is issued, but no tripping is initiated. Instead, an open command is issued to the pressure relief valve to release pressure. When the static pressure falls below the closing pressure, a reset command is sent to the pressure relief valve, causing it to reset.

[0063] It should be noted that the pressure relief valve itself has an action instruction receiving module for receiving an open / reset instruction, and also has an action state feedback module for feeding back the real-time action state of the pressure relief valve.

[0064] In another embodiment, the present disclosure further provides a drive control device for an on-load tap changer oil chamber pressure relief valve, comprising:

[0065] Acquisition module, used to obtain dynamic pressure signal, static pressure signal, voltage and current signal in the oil chamber of the on-load tap changer;

[0066] a first judgment module, configured to judge a pressure rise type in the oil chamber based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer;

[0067] a second judgment module, configured to judge the type of arc fault in the oil compartment of the on-load tap changer based on the acquired voltage and current signals in the oil compartment;

[0068] The control module is used to control the pressure relief valve to perform corresponding actions based on the pressure rise type and the arc fault type.

[0069] In another embodiment, the apparatus further comprises:

[0070] The calculation module is used to integrate the acquired dynamic pressure signal and static pressure signal to obtain the pressure measurement value in the oil chamber.

[0071] In another embodiment, the apparatus further comprises:

[0072] The correction module is used to correct the pressure measurement value in the oil chamber to obtain the actual pressure value in the oil chamber.

[0073] In another embodiment, the apparatus further comprises:

[0074] The first extraction module is used to extract the time domain characteristics of the voltage and current signals and determine whether an arc fault occurs in the oil chamber based on the time domain characteristics;

[0075] The second extraction module is used to extract the frequency domain characteristics of voltage and current, and determine the type of arc fault in the oil chamber according to the frequency domain characteristics.

[0076] In another embodiment, the present disclosure further proposes a readable storage medium, wherein the readable storage medium stores a program, and the program can be called by a processor to execute any of the methods described above.

[0077] In another embodiment, the present disclosure further provides an electronic device, wherein the electronic device includes:

[0078] Acquisition module, used to collect dynamic pressure signal, static pressure signal, voltage and current signal in the oil compartment of the on-load tap changer;

[0079] one or more processors;

[0080] A memory for storing one or more programs, wherein the programs are configured to be executed by the one or more processors, wherein the one or more programs are executed by the processors to perform any of the above methods to control the pressure relief valve to perform corresponding actions based on the dynamic pressure signal, static pressure signal, and voltage and current signals in the oil compartment of the on-load tap changer collected by the collection module.

[0081] The above general description of the invention and the description of its specific embodiments involved in this application should not be understood as limiting the technical solutions of the invention. Based on the disclosure of this application, those skilled in the art may, without violating the constituent elements of the invention involved, add, subtract, or combine the disclosed technical features in the above general description and / or specific embodiments (including examples) to form other technical solutions within the scope of protection of this application.

Claims

1. A method for driving and controlling an on-load tap changer oil chamber pressure relief valve, wherein: The method comprises the following steps: Obtain dynamic pressure signal, static pressure signal, voltage and current signal in the oil compartment of the on-load tap changer; Based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer, determining whether the pressure rise type in the oil chamber is a surge pressure rise; Based on the acquired voltage and current signals in the oil compartment of the on-load tap changer, determining whether the arc fault type in the oil compartment is a continuous arc fault; The pressure relief valve is controlled to perform corresponding actions based on the pressure rise type and arc fault type.

2. The method according to claim 1, wherein The step of determining the pressure rise type in the oil chamber based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer comprises the following steps: Get the pressure measurement value in the oil chamber; Correcting the pressure measurement value to obtain the actual pressure value; Determine the type of pressure rise in the oil chamber based on the actual pressure value.

3. The method according to claim 2, wherein: The obtaining of the pressure measurement value in the oil chamber includes: integrating the obtained dynamic pressure signal and static pressure signal.

4. The method according to claim 1, wherein The method of determining the type of arc fault in the on-load tap changer oil compartment based on the obtained voltage and current signals in the oil compartment comprises the following steps: Extract the time domain characteristics of voltage and current, and judge whether an arc fault occurs in the oil chamber based on the time domain characteristics; The frequency domain characteristics of voltage and current are extracted, and the type of arc fault in the oil chamber is determined based on the frequency domain characteristics.

5. A drive control device for an on-load tap changer oil chamber pressure relief valve, comprising: Acquisition module, used to obtain dynamic pressure signal, static pressure signal, voltage and current signal in the oil chamber of the on-load tap changer; a first judgment module, configured to judge whether the pressure rise type in the oil chamber is a surge pressure rise based on the acquired dynamic pressure signal and static pressure signal in the oil chamber of the on-load tap changer; a second judgment module, configured to judge whether the arc fault in the oil compartment of the on-load tap changer is a continuous arc fault based on the acquired voltage and current signals in the oil compartment of the on-load tap changer; The control module is used to control the pressure relief valve to perform corresponding actions based on the pressure rise type and the arc fault type.

6. The device according to claim 5, wherein The device further comprises: The calculation module is used to integrate the acquired dynamic pressure signal and static pressure signal to obtain the pressure measurement value in the oil chamber.

7. The device according to claim 6, wherein The device further comprises: a correction module, which is used to correct the pressure measurement value in the oil chamber to obtain the actual pressure value in the oil chamber.

8. The device according to claim 5, wherein The device further comprises: The first extraction module is used to extract the time domain characteristics of the voltage and current signals and determine whether an arc fault occurs in the oil chamber based on the time domain characteristics; The second extraction module is used to extract the frequency domain characteristics of voltage and current, and determine the type of arc fault in the oil chamber according to the frequency domain characteristics.

9. A readable storage medium, wherein: The readable storage medium stores a program, and the program can be called by a processor to execute the method according to any one of claims 1 to 4.

10. An electronic device, wherein: The electronic device comprises: Acquisition module, used to collect dynamic pressure signal, static pressure signal, voltage and current signal in the oil compartment of the on-load tap changer; one or more processors; a memory for storing one or more programs, wherein the programs are configured to be executed by the one or more processors, wherein the one or more programs are executed by the processors according to the method according to any one of claims 1 to 4, so as to control the pressure relief valve to perform corresponding actions based on the dynamic pressure signal, static pressure signal, and voltage and current signals in the on-load tap changer oil compartment collected by the collection module.

Images