A portable parallel thyristor rapid pairing measuring instrument and method

Abstract

The present application relates to a kind of portable parallel thyristor quick pairing measuring instrument and method, belong to power electronic equipment maintenance tool and method technical field.The technical scheme of the present application is: reference thyristor is installed in reference thyristor measuring fixture (1), connects reference thyristor measurement circuit;Thyristor to be measured is installed in thyristor to be measured measuring fixture (2), connects thyristor to be measured measurement circuit;The output end of common constant-current source circuit (3) is simultaneously connected reference thyristor and thyristor to be measured;Comparison type indicating module (4) is connected between reference thyristor measurement circuit and thyristor to be measured measurement circuit, synchronous trigger circuit (5) is connected reference thyristor and thyristor to be measured, and reference thyristor and thyristor to be measured are triggered synchronously.The beneficial effects of the present application are: effectively guarantee the scientificity and accuracy of pairing screening, simple structure, low cost, convenient operation.

Description

Technical Field

[0001] This invention relates to a portable parallel thyristor rapid pairing measuring instrument, belonging to the technical field of power electronic equipment maintenance tools and methods. Background Technology

[0002] At the factory's intermediate frequency furnace repair site, conditions are limited, with a lack of professional testing equipment and skilled engineers. When the parallel thyristors in the inverter bridge fail, repair electricians can usually only use a multimeter to measure the thyristor's condition, but cannot determine if its parameters are compatible. Randomly replacing thyristors with incompatible parameters can lead to imbalance in the power distribution, creating a potential risk of the newly replaced device burning out again in a short period.

[0003] Currently, on-site maintenance faces the following challenges: 1. Lack of professional instruments: Large-scale professional thyristor testers are expensive, bulky, and complex to operate, making them difficult to popularize in repair workshops and for field use.

[0004] 2. Reliance on personal experience: Pairing work heavily relies on the experience of the repairman. Using a multimeter to measure resistance is extremely inaccurate and cannot reflect the critical difference in on-state voltage drop.

[0005] 3. Inefficient: It requires manual measurement, recording, and comparison of each spare part, which is tedious and prone to errors.

[0006] 4. Lack of intuitive judgment: Repairmen need a "foolproof" tool that can quickly give intuitive conclusions of "yes / no" or "which is a better match," rather than complex parameter readings.

[0007] Therefore, there is an urgent need for a portable tool that is inexpensive, easy to operate, and can quickly provide intuitive matching results. Summary of the Invention

[0008] The purpose of this invention is to provide a portable parallel thyristor rapid pairing measuring instrument and method. Based on the "on-state voltage drop consistency" golden rule of parallel pairing, it effectively ensures the scientificity and accuracy of pairing and screening by directly comparing the voltage drop difference. The instrument has a simple structure, low cost, and convenient operation, enabling ordinary maintenance electricians to accurately complete the pairing of thyristors on-site, effectively solving the above-mentioned problems existing in the background technology.

[0009] The technical solution of this invention is: a portable parallel thyristor rapid pairing measuring instrument, comprising a reference thyristor measuring fixture, a thyristor under test measuring fixture, a common constant current source circuit, a comparator indicator module, a synchronous trigger circuit, and a power supply module. The reference thyristor is installed in the reference thyristor measuring fixture, and its leads are connected to the reference thyristor measuring circuit. The thyristor under test is installed in the thyristor under test measuring fixture, and its leads are connected to the thyristor under test measuring circuit. The output terminal of the common constant current source circuit is simultaneously connected to the reference thyristor and the thyristor under test. The comparator indicator module is connected between the reference thyristor measuring circuit and the thyristor under test measuring circuit, and the output terminal of the comparator indicator module is connected to a center zero-position pointer meter. The synchronous trigger circuit is connected to the reference thyristor and the thyristor under test, and synchronously triggers the reference thyristor and the thyristor under test.

[0010] The comparative indicator module is either a high-impedance voltage comparator or a differential amplifier, and its input terminals are respectively connected to the two ends of the reference thyristor and the thyristor under test.

[0011] The test current provided by the common constant current source circuit is 5%-15% of the rated current of the thyristor.

[0012] The power module is an adjustable DC power module.

[0013] It also includes a housing, which is a portable box-type structure, and a common constant current source circuit, a comparator indicator module, a synchronous trigger circuit, a power supply module, and a center zero-position pointer meter are installed inside the housing.

[0014] An application method for a portable parallel thyristor rapid pairing measuring instrument includes the following steps: (1) Connect the reference thyristor and the thyristor under test to the reference thyristor measuring fixture and the thyristor under test measuring fixture, respectively; (2) Start the synchronous trigger circuit and the common constant current source circuit, and select the trigger reference thyristor and the thyristor under test to conduct in sequence; (3) Observe the output of the comparative indicator module; (4) Based on the display of the center zero-position pointer meter, directly determine whether the parameter matching degree between the thyristor under test and the reference thyristor is within the allowable range.

[0015] When there is more than one thyristor to be tested, the thyristor to be tested is connected to the measuring fixture in turn, and all the thyristors to be tested are compared with the same reference thyristor. The thyristor to be tested with the closest indication result is selected as the parallel pairing object.

[0016] The beneficial effects of this invention are: by using the golden rule of parallel pairing based on "on-state voltage drop consistency" and by directly comparing the voltage drop difference, the scientificity and accuracy of pairing and screening are effectively guaranteed. The structure is simple, the cost is low, and the operation is convenient, enabling ordinary maintenance electricians to accurately complete the pairing of thyristors on-site. Attached Figure Description

[0017] Figure 1 This is a structural block diagram of the present invention; Figure 2 This is the circuit connection diagram of the present invention; Figure 3 This is a schematic diagram of the structure of the present invention; In the diagram: 1. Reference thyristor measurement fixture; 2. Thyristor under test measurement fixture; 3. Common constant current source circuit; 4. Comparison indicator module; 5. Synchronous trigger circuit; 6. Power supply module; 7. Center zero-position pointer meter; 8. Reference thyristor measurement circuit; 9. Thyristor under test measurement circuit; 10. Power indicator light; 11. Trigger indicator light; 12. Power switch; 13. Reference / under test selection switch. Detailed Implementation

[0018] To make the purpose, technical solutions, and advantages of the invention's embodiments clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only a small part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0019] A portable parallel thyristor rapid pairing measuring instrument includes a reference thyristor measuring fixture 1, a test thyristor measuring fixture 2, a common constant current source circuit 3, a comparator indicator module 4, a synchronous trigger circuit 5, and a power supply module 6. The reference thyristor is installed in the reference thyristor measuring fixture 1, and its leads are connected to the reference thyristor measuring circuit. The test thyristor is installed in the test thyristor measuring fixture 2, and its leads are connected to the test thyristor measuring circuit. The output of the common constant current source circuit 3 is connected to both the reference thyristor and the test thyristor. The comparator indicator module 4 is connected between the reference thyristor measuring circuit and the test thyristor measuring circuit, and its output is connected to a center zero-position pointer meter 7. The synchronous trigger circuit 5 is connected to the reference thyristor and the test thyristor, and synchronously triggers both the reference thyristor and the test thyristor.

[0020] The comparative indicator module 4 is either a high-impedance voltage comparator or a differential amplifier, and its input terminals are respectively connected to the two ends of the reference thyristor and the thyristor under test.

[0021] The test current provided by the common constant current source circuit 3 is 5%-15% of the rated current of the thyristor.

[0022] The power module 6 is an adjustable DC power module.

[0023] It also includes a housing, which is a portable box-type structure. A common constant current source circuit 3, a comparator indicator module 4, a synchronous trigger circuit 5, a power supply module 6, and a center zero-position pointer meter 7 are installed inside the housing.

[0024] An application method for a portable parallel thyristor rapid pairing measuring instrument includes the following steps: (1) Connect the reference thyristor and the thyristor under test to the reference thyristor measuring fixture and the thyristor under test measuring fixture, respectively; (2) Start the synchronous trigger circuit and the common constant current source circuit, and select the trigger reference thyristor and the thyristor under test to conduct in sequence; (3) Observe the output of the comparative indicator module; (4) Based on the display of the center zero-position pointer meter, directly determine whether the parameter matching degree between the thyristor under test and the reference thyristor is within the allowable range.

[0025] When there is more than one thyristor to be tested, the thyristor to be tested is connected to the measuring fixture in turn, and all the thyristors to be tested are compared with the same reference thyristor. The thyristor to be tested with the closest indication result is selected as the parallel pairing object.

[0026] In practical applications, the present invention includes: • Case: Portable case design; • Reference thyristor measurement fixture: During measurement, a pre-selected reference thyristor with known parameters is installed in the reference thyristor measurement fixture, and the lead wire is connected to the corresponding terminal of this invention to introduce the reference thyristor measurement circuit; • Test thyristor measurement fixture: During measurement, a test thyristor is installed in the test thyristor measurement fixture, and the lead wire is connected to the corresponding terminal of the present invention to introduce the test thyristor measurement circuit; • Common constant current source circuit: used to simultaneously provide equal test current to the reference thyristor and the thyristor under test; • Comparative indicator module: Connected between the reference thyristor measurement circuit and the measurement circuit of the thyristor under test, it is used to directly compare the on-state voltage drop difference between the two. • Synchronous trigger circuit: used to simultaneously trigger the conduction of the reference thyristor and the thyristor under test; • Power module: AC power is rectified into DC power to supply power to each unit; The comparator indicator module is a high-impedance voltage comparator or differential amplifier, with its inputs connected to the two ends of a reference thyristor and the thyristor under test, respectively, to acquire the on-state voltage drop between them. The output of the comparator indicator module is connected to a center-zero pointer meter. The pointer of the center-zero pointer meter is centered at zero. If the voltage drop of the thyristor under test is lower than that of the reference thyristor, the pointer deflects to one side; if the voltage drop of the thyristor under test is higher than that of the reference thyristor, the pointer deflects to the other side. The larger the deflection angle, the greater the parameter difference. The dial has a green "pass" zone and a red "fail" zone.

[0027] The common constant current source circuit provides a test current of 5%-15% of the thyristor's rated current, ensuring that the device is only slightly conductive. This meets the measurement requirements without requiring a complex heat dissipation device, thus simplifying and porting the instrument. Example

[0028] The reference thyristor measurement fixture comes pre-loaded with a high-performance reference thyristor VT0. Upon triggering, the common constant current source circuit outputs a stable 50A DC current, which flows simultaneously through VT0 and the thyristor under test VTx loaded into the measurement fixture.

[0029] The on-state voltage drops Vf0 and Vfx of VT0 and VTx are fed into a comparator indicator module, which is a differential amplifier with high input impedance. The output of the differential amplifier drives a center-zero pointer meter.

[0030] • If VTx and VT0 are perfectly matched (Vfx = Vf0), the differential output is zero, and the pointer of the center zero-position pointer meter points to the center "0" position.

[0031] • If the VTx voltage drops (Vfx < Vf0), the meter needle will deflect in the "-" direction.

[0032] • If the VTx voltage drop is high (Vfx > Vf0), the meter needle will deflect in the "+" direction.

[0033] On the dial of a center-zero pointer meter, the range of "-0.5" and "+0.5" is marked in green, indicating that devices within this range can be used in parallel with a reference tube. Ranges outside this range are marked in red, indicating a mismatch.

[0034] This invention is extremely simple and portable: it eliminates the need for complex microprocessors, displays and precision measurement circuits, and adopts a direct analog comparison scheme. It has a simple structure, small size, light weight and extremely low cost, making it very suitable for on-site carrying and use.

[0035] The operation is intuitive and efficient: maintenance personnel do not need to understand complex parameters. They only need to put the part to be tested into the fixture, and after triggering, they can immediately determine whether it is compatible by observing the pointer indication. This achieves "plug and test, clear at a glance".

[0036] The principle is scientific and reliable: Based on the golden rule of parallel pairing, "consistency of on-state voltage drop", the scientific nature and accuracy of pairing and screening are effectively guaranteed by directly comparing the voltage drop difference.

[0037] Improved maintenance quality: It fundamentally solves the problem of "randomly replacing parts" in on-site maintenance, effectively prevents cascading tube burnout failures caused by improper flow equalization, and extends the stable operation time of the equipment.

Claims

1. A portable parallel thyristor rapid pairing measuring instrument, characterized in that: The device includes a reference thyristor measuring fixture (1), a thyristor under test measuring fixture (2), a common constant current source circuit (3), a comparator indicator module (4), a synchronous trigger circuit (5), and a power supply module (6). The reference thyristor is installed in the reference thyristor measuring fixture (1), and its leads are connected to the reference thyristor measuring circuit. The thyristor under test is installed in the thyristor under test measuring fixture (2), and its leads are connected to the thyristor under test measuring circuit. The output of the common constant current source circuit (3) is connected to both the reference thyristor and the thyristor under test. The comparator indicator module (4) is connected between the reference thyristor measuring circuit and the thyristor under test measuring circuit, and the output of the comparator indicator module (4) is connected to a center zero-position pointer meter (7). The synchronous trigger circuit (5) is connected to the reference thyristor and the thyristor under test, and synchronously triggers both the reference thyristor and the thyristor under test.

2. The portable parallel thyristor rapid pairing measuring instrument according to claim 1, characterized in that: The comparative indicator module (4) is either a high-impedance voltage comparator or a differential amplifier, and its input terminals are respectively connected to the two ends of the reference thyristor and the thyristor under test.

3. The portable parallel thyristor rapid pairing measuring instrument according to claim 1, characterized in that: The test current provided by the common constant current source circuit (3) is 5%-15% of the rated current of the thyristor.

4. A portable parallel thyristor rapid pairing measuring instrument according to claim 1, characterized in that: The power module (6) is an adjustable DC power module.

5. A portable parallel thyristor rapid pairing measuring instrument according to claim 1, characterized in that: It also includes a housing, which is a portable box-type structure, and a common constant current source circuit (3), a comparator indicator module (4), a synchronous trigger circuit (5), a power supply module (6), and a center zero-position pointer meter (7) are installed inside the housing.

6. An application method for a portable parallel thyristor rapid pairing measuring instrument, characterized in that... Includes the following steps: (1) Connect the reference thyristor and the thyristor under test to the reference thyristor measuring fixture and the thyristor under test measuring fixture, respectively; (2) Start the synchronous trigger circuit and the common constant current source circuit, and select the trigger reference thyristor and the thyristor under test to conduct in sequence; (3) Observe the output of the comparative indicator module; (4) Based on the display of the center zero-position pointer meter, directly determine whether the parameter matching degree between the thyristor under test and the reference thyristor is within the allowable range.

7. The application method of the portable parallel thyristor rapid pairing measuring instrument according to claim 6, characterized in that, When there is more than one thyristor to be tested, the thyristor to be tested is connected to the measuring fixture in turn, and all the thyristors to be tested are compared with the same reference thyristor. The thyristor to be tested with the closest indication result is selected as the parallel pairing object.

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