Multi-contact parallel detection method suitable for gas relay inspection system

Abstract

The application provides a multi-contact parallel detection method suitable for a gas relay inspection system and belongs to the technical field of gas relay detection. The method comprises the following steps: connecting all heavy gas contacts and all light gas contacts of a gas relay by using a contact signal acquisition device; the contact signal acquisition device is used for acquiring the closing signals of the heavy gas contacts and the light gas contacts and transmitting the closing signals to the gas relay inspection system; performing multiple flow rate value tests, and automatically recording the flow rate values of each heavy gas contact when each heavy gas contact is closed in each test by using the gas relay inspection system; performing multiple gas volume value tests, and automatically recording the gas volume values of each light gas contact when each light gas contact is closed in each test by using the gas relay inspection system; and judging whether the measured gas relay conforms to the setting value according to the flow rate values of each heavy gas contact when the heavy gas contact is closed and the gas volume values of each light gas contact when the light gas contact is closed. The application can improve the efficiency and reliability of the gas relay inspection work.

Description

Technical Field

[0001] This invention belongs to the field of gas relay testing technology, specifically relating to a multi-contact parallel testing method suitable for gas relay testing systems. Background Technology

[0002] Gas relays (or gas-powered relays) are crucial non-electrical protection devices for oil-immersed transformers. They are used to detect and protect against internal transformer faults, effectively addressing the issue that electrical protection only cuts off power when an internal fault develops into a multi-turn short circuit or a short circuit to ground. As a primary protection measure for transformers, they can instantly disconnect faulty equipment. When a fault occurs inside the transformer, the oil decomposes to produce gas or causes an oil surge, triggering the gas relay contacts to activate, connecting the designated control circuit, and promptly issuing an alarm signal (light gas) or activating protective components to automatically disconnect the transformer (heavy gas). The alarm signal is related to the gas volume, while the heavy gas alarm is related to the operating flow rate. To ensure the gas relay effectively protects the transformer, it needs to be tested before leaving the factory, before installation, and during transformer overhauls to guarantee its protective effectiveness.

[0003] Currently, oil pump-type gas relay testing benches are commonly used to test the flow rate and gas volume values ​​of gas relays. Portable and online gas relay testing systems are also available. However, all of these methods require repeated testing of each of the relay's multiple operating contacts, resulting in low efficiency and high repetitive labor. Taking the 80-caliber gas relay commonly used in domestic power engineering as an example, it typically has 2-3 heavy gas operating contacts and 1-2 light gas operating contacts. Furthermore, due to factors such as equipment manufacturing processes, the operating values ​​of the multiple contacts for light and heavy gas are often inconsistent. Therefore, when using the aforementioned devices for testing, each pair of functional contacts needs to be tested multiple times.

[0004] Therefore, the existing working mode of inspecting each contact individually greatly limits the efficiency of gas relay inspection and calibration. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a multi-contact parallel detection method suitable for gas relay testing systems, which can improve the efficiency and reliability of gas relay testing work, in order to address the shortcomings of the prior art.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A multi-contact parallel detection method applicable to a gas relay testing system, the method comprising: A contact signal acquisition device is used to connect all heavy gas contacts and all light gas contacts of the gas relay; the contact signal acquisition device is used to acquire the closing signals of the heavy gas contacts and light gas contacts and transmit them to the gas relay testing system; Multiple flow rate tests were performed, and the flow rate value at the closing of each heavy gas contact was automatically recorded using a gas relay testing system in each test. Perform multiple gas volume tests and use a gas relay testing system to automatically record the gas volume value when each light gas contact is closed in each test. Based on the flow rate value when each heavy gas contact is closed and the gas volume value when each light gas contact is closed, determine whether the gas relay being tested meets the setting value.

[0007] Furthermore, a single flow rate test automatically ends when all heavy gas connections are closed or the flow rate exceeds the limit.

[0008] Furthermore, the flow rate test method includes: using a gas relay testing system to slowly increase the flow rate of the transformer oil inside the gas relay being tested from 0 m / s.

[0009] Furthermore, the method for determining if the flow rate exceeds the limit includes: determining the upper limit of the flow rate based on the parameters of the gas relay to be tested, and determining whether the transformer oil flow rate exceeds the upper limit of the flow rate.

[0010] Furthermore, a single gas volume test automatically terminates when all light gas contacts are closed or the gas volume exceeds the limit.

[0011] Furthermore, the gas volume value test method includes: using a gas relay testing system to gradually drain the transformer oil inside the gas relay being tested.

[0012] Furthermore, the method for determining if the gas volume value exceeds the limit includes: determining the upper limit of the gas volume value based on the parameters of the gas relay to be tested, and determining whether the gas volume value exceeds the upper limit of the gas volume value.

[0013] Furthermore, the contact signal acquisition device is equipped with lead wires for connecting to the heavy gas contact and light gas contact of the gas relay.

[0014] Furthermore, there are at least three lead wires connected to the heavy gas contact point and at least two lead wires connected to the light gas contact point.

[0015] Furthermore, when the contact signal acquisition device transmits the contact closure signal to the gas relay testing system, it also transmits the number of the lead wire connected to the contact.

[0016] Gas relay-based gas protection utilizes a gas relay that reflects the internal gas state of the transformer to protect it. This facilitates timely detection or disconnection of faulty equipment, preventing accidents from occurring or escalating. Gas protection is divided into light gas protection and heavy gas protection. Light gas protection occurs when overheating or partial discharge inside the transformer causes the transformer oil temperature to rise and decompose, producing a certain amount of gas that accumulates in the relay. Once a certain amount is reached, the light gas reed contact closes, sending a light gas signal (alarm). Heavy gas protection occurs when a severe fault inside the transformer causes a strong oil flow that directly impacts the baffle. The heavy gas baffle is forced open at a certain angle, closing the heavy gas reed contact and generating a heavy gas signal (trip).

[0017] To ensure the safety and reliability of gas relays, their gas protection function needs to be tested regularly. Based on the principle of gas protection, the sensitivity of light gas protection depends on the gas volume inside the gas relay, while the sensitivity of heavy gas protection depends on the flow rate of the transformer oil. Therefore, the existing testing items for gas relays all include gas volume tests related to light gas protection and flow rate tests related to heavy gas protection.

[0018] Current gas relay testing devices mostly install the gas relay in the oil circuit for testing, such as conventional oil pump-type gas relay testing benches and newer portable gas relay testing systems. These testing devices largely utilize an oil pump as the flow rate power source to simulate the state of the gas relay under test when it is installed and operating in a transformer. By connecting the heavy gas contact and the light gas contact, when an electrical signal indicating the closure of either the heavy or light gas contact is received, it is determined that either heavy or light gas protection has been activated. The transformer oil flow rate or the gas volume within the relay at the moment of activation is the setting value that needs to be tested.

[0019] However, current gas relays have multiple heavy gas and light gas contacts, and due to factors such as equipment manufacturing processes, the operating values ​​of these contacts are often inconsistent. Therefore, it is necessary to obtain the setting value for each contact. Existing gas relay testing equipment can only connect one heavy gas contact or one light gas contact at a time, meaning it can only test the flow rate of one heavy gas contact or the gas volume of one light gas contact at a time. Furthermore, regulations require multiple tests for flow rate and gas volume, necessitating repeated testing of each of the relay's multiple operating contacts, resulting in low efficiency and high repetitive workload.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: The gas relay testing system of this invention includes a signal acquisition device with lead wires for connecting to the gas relay under test. These lead wires include at least three heavy gas lead wires and at least two light gas lead wires, each used for a one-to-one connection to a heavy gas contact and a light gas contact. The signal acquisition device transmits the acquired contact closure signal to the gas relay testing system, along with the lead wire number, enabling the system to identify the closure of a heavy or light gas contact based on the lead wire number. Therefore, the gas relay testing system, using the signal acquisition device, can acquire closure signals from all light and heavy gas contacts, eliminating the need to test each gas contact individually during gas relay testing, thus improving work efficiency.

[0021] This invention, by connecting all heavy gas contacts and all light gas contacts of a gas relay using a contact signal acquisition device, allows for multiple flow rate tests and multiple gas volume tests. During the flow rate test, the gas relay testing system automatically records the flow rate value when each heavy gas contact closes in each test. Similarly, during the gas volume test, the same system automatically records the gas volume value when each light gas contact closes in each test. Finally, based on the flow rate value when each heavy gas contact closes and the gas volume value when each light gas contact closes, the system determines whether the tested gas relay meets the setting requirements. Therefore, this invention enables parallel detection of the relevant flow rate values ​​for each heavy gas contact, allowing for the testing of all heavy gas contacts in a single flow rate test; it also enables parallel detection of the relevant gas volume values ​​for each light gas contact, allowing for the testing of all light gas contacts in a single gas volume test.

[0022] The parallel testing method of this invention also includes protection criteria, setting upper limits for flow rate and gas volume based on the parameters of the gas relay under test. During the testing process, if the transformer oil flow rate increases beyond the upper limit, it indicates that the unclosed heavy gas contact is malfunctioning or malfunctioning, and the current flow rate test is terminated directly. Similarly, if the gas volume increases beyond the preset upper limit, and there are still unclosed light gas contacts, it indicates that the unclosed light gas contacts are malfunctioning or malfunctioning, and the current gas volume test is terminated directly. Therefore, when a contact malfunctions or malfunctions, this invention automatically stops the current test and can automatically proceed to the next test as needed, preventing the flow rate or gas volume from increasing indefinitely, reducing the risk of damage to the gas relay under test, and ensuring the normal operation of other normal contact testing procedures. Attached Figure Description

[0023] The present invention will now be described in further detail with reference to the accompanying drawings.

[0024] Figure 1 : Flowchart of the present invention; Figure 2 Schematic diagram of parallel detection logic for heavy gas contacts; Figure 3 Schematic diagram of parallel detection logic for light gas contacts. Detailed Implementation

[0025] To better understand the present invention, the content of the invention is further clearly illustrated below with reference to embodiments and accompanying drawings. However, the scope of protection of the present invention is not limited to the embodiments described below. Numerous specific details are set forth in the following description to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details.

[0026] See Figure 1 The purpose of this embodiment is to provide a multi-contact parallel detection method suitable for gas relay testing systems. The method includes: Step S1: Connect the contact signal acquisition device to all heavy gas contacts and light gas contacts of the gas relay under test.

[0027] The contact signal acquisition device is equipped with lead wires for connecting to the gas relay under test. These lead wires include at least three heavy gas lead wires and at least two light gas lead wires. The heavy gas lead wires are used for one-to-one connection to the heavy gas contacts of the gas relay under test, and the light gas lead wires are used for one-to-one connection to the light gas contacts of the gas relay under test. After connecting the heavy and light gas contacts, the contact signal acquisition device can acquire the closing signals of these contacts and transmit the closing signals and lead wire number information to the gas relay testing system. The gas relay testing system identifies the closing signals of the contacts and identifies the heavy or light gas contact that closed based on the lead wire number. This application can utilize existing gas relay testing systems.

[0028] After connecting the gas relay under test to the gas relay testing system, use this step to connect the lead wire of the contact signal acquisition device to the corresponding heavy gas contact and light gas contact.

[0029] Step S2: Perform a gas relay flow rate test and record the flow rate value when each heavy gas contact is closed.

[0030] The gas relay testing system is activated to simulate the state of the gas relay under test during transformer installation and operation. The flow rate of the transformer oil inside the gas relay is slowly increased from 0 m / s. As the increased flow rate pushes the gas relay baffle, the permanent magnet fixed to the baffle attracts the normally open contact of the heavy gas reed switch to close. The gas relay testing system receives the closing signal of the heavy gas contact using a contact signal acquisition device and automatically records the current flow rate value. The flow rate is continuously increased until all heavy gas contacts on the gas relay under test are closed. The test ends when all contacts are closed.

[0031] Meanwhile, if the transformer oil flow rate increases beyond the preset upper limit, such as exceeding 1.5 m / s and exceeding 50% of the set value, and there are still unclosed heavy gas contacts during this period, it indicates that the unclosed heavy gas contacts are malfunctioning or malfunctioning, and the test will be terminated immediately. The upper limit of the flow rate can be determined based on the parameters of the gas relay under test.

[0032] Due to factors such as installation process, the operating values ​​of heavy gas contacts are usually not completely consistent. Therefore, a single flow rate test must be completed only when all heavy gas contacts are closed or the flow rate exceeds the limit. This invention enables the inspection of all heavy gas contacts in a single flow rate test.

[0033] The gas relay flow rate test requires multiple (usually three rounds) repetitions according to the procedure requirements. Therefore, this step should be performed multiple times until the preset number of tests is completed. Figure 2 The diagram shows the parallel detection logic of heavy gas contacts. In each flow rate test, the flow rate test of three heavy gas contacts (heavy gas contact A, heavy gas contact B and heavy gas contact C) is completed.

[0034] Step S3: Perform a gas volume test on the gas relay and record the gas volume value when each light gas contact is closed.

[0035] The gas relay testing system is activated, simulating the state of the gas relay under test during transformer installation and operation. The system gradually discharges transformer oil from the gas relay, increasing the gas volume. As buoyancy decreases, the float or oil box descends. When the permanent magnet fixed to it attracts the normally open contact of the light gas reed switch to close, the gas relay testing system receives the closing signal from the light gas contact using a contact signal acquisition device and automatically records the current gas volume. Oil discharge continues, increasing the gas volume, until all light gas contacts on the gas relay under test are closed. The test ends when all contacts are closed.

[0036] Meanwhile, if the gas volume increases beyond the preset upper limit, and any light gas contacts remain open during this period, it indicates that the open light gas contacts are malfunctioning or malfunctioning, and the test will be terminated immediately. The upper limit of the gas volume is determined based on the parameters of the gas relay under test.

[0037] Due to factors such as installation process, the operating values ​​of light gas contacts are usually not completely consistent. Therefore, a single gas volume test must be completed only when all light gas contacts are closed or the gas volume exceeds the limit. This invention enables the inspection of all light gas contacts in a single gas volume test.

[0038] The gas volume test for the gas relay requires multiple (usually three) repetitions according to the procedure. Therefore, this step should be performed multiple times until the preset number of tests is completed. Figure 3 The diagram shows the parallel detection logic of the light gas contacts. In each gas volume test, the gas volume test of two light gas contacts (light gas contact A and light gas contact B) is completed.

[0039] Step S4: Based on the flow rate value when each heavy gas contact is closed and the gas volume value when each light gas contact is closed, as recorded by the gas relay testing system, determine whether the gas relay under test meets the setting value.

[0040] It should be noted that the numbers of the relevant steps in this embodiment do not represent the order of execution. For example, the order of steps S2 and S3 can be changed. Those skilled in the art can change the order of the above steps without departing from the protection scope of this invention.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention, as long as they do not depart from the spirit and scope of the technical solutions of the present invention, should be covered within the scope of the claims of the present invention.

Claims

1. A multi-contact parallel detection method suitable for gas relay testing systems, characterized in that: include: Connect all heavy gas contacts and all light gas contacts of the gas relay using a contact signal acquisition device; The contact signal acquisition device is used to acquire the closing signals of heavy gas contacts and light gas contacts and transmit them to the gas relay testing system. Multiple flow rate tests were performed, and the flow rate value at the closing of each heavy gas contact was automatically recorded using a gas relay testing system in each test. Perform multiple gas volume tests and use a gas relay testing system to automatically record the gas volume value when each light gas contact is closed in each test. Based on the flow rate value when each heavy gas contact is closed and the gas volume value when each light gas contact is closed, determine whether the gas relay being tested meets the setting value.

2. The multi-contact parallel detection method for gas relay testing systems according to claim 1, characterized in that: A single flow rate test will automatically end when all heavy gas connections are closed or the flow rate exceeds the limit.

3. The multi-contact parallel detection method for gas relay testing systems according to claim 2, characterized in that: The flow rate test method includes: using a gas relay testing system to slowly increase the flow rate of the transformer oil inside the gas relay being tested from 0 m / s.

4. The multi-contact parallel detection method for gas relay testing systems according to claim 3, characterized in that: The methods for determining if the flow rate exceeds the limit include: determining the upper limit of the flow rate based on the parameters of the gas relay to be tested, and determining whether the transformer oil flow rate exceeds the upper limit of the flow rate.

5. The multi-contact parallel detection method for gas relay testing systems according to claim 1, characterized in that: A single gas volume test will automatically end when all light gas contacts are closed or the gas volume exceeds the limit.

6. The multi-contact parallel detection method for gas relay testing systems according to claim 5, characterized in that: The gas volume test method includes: using a gas relay testing system to gradually drain the transformer oil inside the gas relay being tested.

7. The multi-contact parallel detection method for gas relay testing systems according to claim 6, characterized in that: The methods for determining whether a gas volume exceeds the limit include: determining the upper limit of the gas volume based on the parameters of the gas relay to be tested, and then determining whether the gas volume exceeds the upper limit of the gas volume.

8. The multi-contact parallel detection method for gas relay testing systems according to claim 1, characterized in that: The contact signal acquisition device is equipped with lead wires for connecting to the heavy gas contact and light gas contact of the gas relay.

9. The multi-contact parallel detection method for a gas relay testing system according to claim 8, characterized in that: There are at least three lead wires connected to the heavy gas contact point and at least two lead wires connected to the light gas contact point.

10. The multi-contact parallel detection method for a gas relay testing system according to claim 9, characterized in that: When transmitting a contact closure signal to the gas relay testing system, the contact signal acquisition device also transmits the number of the lead wire connected to the contact.

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