CN114814512A - Detection system for obtaining thyristor-level impedance of converter valve - Google Patents
Detection system for obtaining thyristor-level impedance of converter valve Download PDFInfo
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R1/00—Details of instruments or arrangements of the types included in groups G01R5/00 - G01R13/00 and G01R31/00
- G01R1/30—Structural combination of electric measuring instruments with basic electronic circuits, e.g. with amplifier
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/08—Measuring resistance by measuring both voltage and current
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/26—Testing of individual semiconductor devices
- G01R31/2607—Circuits therefor
- G01R31/263—Circuits therefor for testing thyristors
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Abstract
The application discloses a detection system for obtaining thyristor-level impedance of a converter valve, which comprises a test signal generation module, a resistance synchronous measurement module, a voltage and current signal acquisition module and an impedance calculation module; the test signal generation module is used for outputting a sinusoidal signal to the target thyristor-level damping loop; the resistance synchronous measurement module comprises five reference resistors with different resistance values, and the target thyristor-level damping loop and the five reference resistors with different resistance values form five groups of impedance loops; the voltage circuit signal acquisition module is used for acquiring the voltage and the current of the five groups of impedance loops; the impedance calculation module is used for obtaining impedance measurement values of the five groups of impedance loops, obtaining an optimal measurement value in the five groups of impedance measurement values, and obtaining a module value of the impedance of the target thyristor-level damping loop. The impedance of thyristor-level damping loop can be rapidly detected, and the safe and stable operation of the direct-current transmission project is assisted.
Description
Technical Field
The application relates to the technical field of thyristor level impedance calculation, in particular to a detection system for obtaining thyristor level impedance of a converter valve.
Background
In recent years, with the rapid development of direct current transmission technology in China, the number of converter stations is increasing day by day, wherein a converter valve is a core device in direct current transmission engineering, and a thyristor has the advantages of large through-current capacity, high withstand voltage level and the like, and is the most common power electronic device in the direct current transmission converter valve at present, the thyristor level is the most basic electrical structural unit of the converter valve, and serious accidents such as phase conversion failure and the like of the converter valve can be caused by faults of the thyristor level, so that the safety and stability of various performances of the thyristor level are the basis for ensuring the safe and stable operation of the converter valve and even the whole direct current transmission engineering. Based on this, the equipment operation and maintenance unit should regularly perform on-site routine tests on the thyristor-level unit of the converter valve, wherein the impedance parameter of the thyristor level is one of the key indexes for measuring the electrical performance of the thyristor-level unit.
In the prior art, a testing system used by a tester for field electrical detection of a thyristor converter valve generally has the defects of poor compatibility, single function, influence of external environment and large impedance measurement deviation, and cannot meet the requirement of high-precision measurement.
Disclosure of Invention
In order to solve the problem that the impedance of a thyristor level of a converter valve cannot be detected quickly and accurately in the prior art, the application discloses a detection system for obtaining the impedance of the thyristor level of the converter valve.
The application discloses a detection system for obtaining thyristor-level impedance of a converter valve, which comprises a test signal generation module, a resistance synchronous measurement module, a voltage and current signal acquisition module and an impedance calculation module; the test signal generation module, the resistance synchronous measurement module, the voltage and current signal acquisition module and the impedance calculation module are sequentially connected;
the test signal generation module is used for being connected with a target thyristor-level damping loop and outputting sinusoidal signals with different frequencies to the target thyristor-level damping loop;
the resistance synchronous measurement module comprises five reference resistors with different resistance values, and the target thyristor-level damping loop and the five reference resistors with different resistance values form five groups of impedance loops;
the voltage circuit signal acquisition module is used for acquiring the voltage and the current of the five groups of impedance loops and acquiring the voltage and the current of the target thyristor-level damping loop;
the impedance calculation module is used for acquiring impedance measurement values of the five groups of impedance loops according to the voltage and the current of the five groups of impedance loops and the voltage and the current of the target thyristor level damping loop;
the impedance calculation module is further used for comparing the impedance measurement values of the five groups of impedance loops with the resistance values of the reference resistors of the five groups of impedance loops to obtain the optimal measurement value of the five groups of impedance measurement values; and the impedance calculation module is also used for acquiring the module value of the impedance of the target thyristor-level damping loop according to the optimal measurement value.
Optionally, the resistance values of the five reference resistors with different resistance values are 1000 Ω, 500 Ω, 100 Ω, 20 Ω and 5 Ω, the impedance loop including the 1000 Ω reference resistor in the five groups of impedance loops is a first impedance loop, the impedance loop including the 500 Ω reference resistor is a second impedance loop, the impedance loop including the 100 Ω reference resistor is a third impedance loop, the impedance loop including the 20 Ω reference resistor is a fourth impedance loop, and the impedance loop including the 5 Ω reference resistor is a fifth impedance loop;
optionally, the comparing the impedance measurement values of the five groups of impedance loops with the resistance values of the reference resistors of the five groups of impedance loops to obtain an optimal measurement value of the five groups of impedance measurement values includes: and if the impedance measurement value of the first impedance loop is 1000-5000 omega, the impedance measurement value of the second impedance loop is 200-1000 omega, the impedance measurement value of the third impedance loop is 50-200 omega, the impedance measurement value of the fourth impedance loop is 10-50 omega, and the impedance measurement value of the fifth impedance loop is 5-10 omega, judging that the impedance measurement value is the optimal measurement value.
Optionally, the test signal generation module includes an AD9850 direct frequency synthesizer, and the AD9850 direct frequency synthesizer is externally connected with a 125MHz clock.
Optionally, the working voltage of the test signal generation module is 5V, and the output signal is a unipolar analog signal of 0-500 mV.
Optionally, the resistance precision of the resistance synchronous measurement module is 0.1%.
Optionally, the voltage and current signal acquisition module includes two operational amplifiers with in-phase inputs, and the two operational amplifiers with in-phase inputs are connected in parallel to form a front-end input stage for increasing the input impedance of the circuit.
Optionally, the voltage-current signal acquisition module further includes a differential operational amplifier, and the front-end input stage is connected in series with the differential operational amplifier to form a triple-operational-amplifier differential amplification circuit.
Optionally, the impedance calculation module uses a DSP chip of a 32-bit processor, and is configured to control data transmission and calculation between the modules.
Optionally, the system further includes an FPGA controller, and the FPGA controller is configured to control an operation state of each module.
The application discloses a detection system for obtaining thyristor-level impedance of a converter valve, which comprises a test signal generation module, a resistance synchronous measurement module, a voltage and current signal acquisition module and an impedance calculation module; the test signal generation module, the resistance synchronous measurement module, the voltage and current signal acquisition module and the impedance calculation module are sequentially connected; the test signal generation module is used for being connected with a target thyristor-level damping loop and outputting sinusoidal signals with different frequencies to the target thyristor-level damping loop; the resistance synchronous measurement module comprises five reference resistors with different resistance values, and the target thyristor-level damping loop and the five reference resistors with different resistance values form five groups of impedance loops; the voltage circuit signal acquisition module is used for acquiring the voltage and the current of the five groups of impedance loops; the impedance calculation module is used for acquiring impedance measurement values of the five groups of impedance loops according to the voltage and the current of the five groups of impedance loops; and the impedance measurement values of the five groups of impedance loops are compared with the resistance values of the reference resistors of the five groups of impedance loops, so that the optimal measurement value of the five groups of impedance measurement values is obtained, and the module value of the impedance of the target thyristor-level damping loop is obtained.
In order to acquire reliable voltage and current values in a target thyristor-level damping loop, a test signal source can output low-voltage alternating-current signals with different frequencies, the signal frequency can be flexibly set according to the actual situation of an application scene, and the application range is wide; the method and the device adopt the FAGA controller to realize the synchronous measurement of the five high-precision reference resistors with different resistance values, can reduce signal interference and improve the accuracy of impedance measurement values; the method adopts the DSP technology, is convenient for data processing, measures five paths of signals at one time, selects the optimal value to output, and has high processing speed and low power consumption; the method and the device can simultaneously detect the running state of the target thyristor level and help the converter valve to replace the thyristor in time; the impedance of thyristor level damping circuit can be detected fast, and the direct current transmission engineering is helped to operate safely and stably.
Drawings
In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a detection system for obtaining thyristor-level impedance of a converter valve according to an embodiment of the present disclosure;
fig. 2 is a schematic circuit diagram of a voltage-current signal acquisition module of a detection system for obtaining thyristor-level impedance of a converter valve according to an embodiment of the present application.
Detailed Description
In order to solve the problem that the impedance of a thyristor level of a converter valve cannot be detected quickly and accurately in the prior art, the application discloses a detection system for obtaining the impedance of the thyristor level of the converter valve.
The application discloses a detection system for obtaining thyristor-level impedance of a converter valve, which is shown in a schematic structural diagram of fig. 1 and comprises a test signal generation module, a resistance synchronous measurement module, a voltage and current signal acquisition module and an impedance calculation module. The test signal generation module, the resistance synchronous measurement module, the voltage and current signal acquisition module and the impedance calculation module are sequentially connected.
The test signal generation module is used for being connected with a target thyristor-level damping loop and outputting sinusoidal signals with different frequencies to the target thyristor-level damping loop. The test signal generation module comprises an AD9850 direct frequency synthesizer, the AD9850 direct frequency synthesizer is externally connected with a 125MHz clock, the working voltage of the test signal generation module is 5V, the output signal is a unipolar analog signal of 0-500mV, and after a direct current component is filtered by using a high-pass filter circuit, a sinusoidal signal with adjustable frequency can be generated and output to the damping loop.
The resistance synchronous measurement module comprises five reference resistors with different resistance values, and measures each damping loop in a measuring range based on a standard for ensuring that the damping loop and an original signal on the reference resistor have a certain amplitude to obtain the most accurate measurement value, so that the influence of a noise signal is as small as possible. And the target thyristor-level damping loop and the five reference resistors with different resistance values form five groups of impedance loops. The resistance values of the five reference resistors with different resistance values are respectively 1000 Ω, 500 Ω, 100 Ω, 20 Ω and 5 Ω, the impedance loop including the 1000 Ω reference resistor in the five groups of impedance loops is a first impedance loop, the impedance loop including the 500 Ω reference resistor is a second impedance loop, the impedance loop including the 100 Ω reference resistor is a third impedance loop, the impedance loop including the 20 Ω reference resistor is a fourth impedance loop, and the impedance loop including the 5 Ω reference resistor is a fifth impedance loop. The resistance precision of the resistance synchronous measurement module is 0.1%. In the application, the precision resistor with the precision of 0.1% is selected to ensure the symmetry of the upper bridge arm and the lower bridge arm, and the amplification gain is set to be 5 times. In the voltage signal acquisition part, in order to ensure the acquisition precision of the high-frequency signal, an AD637 conversion chip with a large bandwidth range and high conversion precision is adopted to acquire the voltage signal.
The voltage circuit signal acquisition module is used for acquiring the voltage and the current of the five groups of impedance loops and acquiring the voltage and the current of the target thyristor-level damping loop. Referring to the circuit schematic diagram of fig. 2, the voltage-current signal acquisition module includes two operational amplifiers with non-inverting inputs, and the two operational amplifiers with non-inverting inputs are connected in parallel to form a front-end input stage for increasing the input impedance of the circuit. The voltage and current signal acquisition module further comprises a differential operational amplifier, and the front-end input stage and the differential operational amplifier are connected in series to form a three-operational-amplifier differential amplification circuit.
And the impedance calculation module is used for acquiring impedance measurement values of the five groups of impedance loops according to the voltage and the current of the five groups of impedance loops and the voltage and the current of the target thyristor-level damping loop. The impedance calculation module adopts a DSP chip of a 32-bit processor, and the DSP is a digital signal processing technology and is used for controlling data transmission and calculation among all modules.
The impedance calculation module is further used for comparing the impedance measurement values of the five groups of impedance loops with the resistance values of the reference resistors of the five groups of impedance loops to obtain the optimal measurement value of the five groups of impedance measurement values; and the impedance calculation module is also used for acquiring the module value of the impedance of the target thyristor-level damping loop according to the optimal measurement value.
The comparing the impedance measurement values of the five groups of impedance loops with the resistance values of the reference resistors of the five groups of impedance loops to obtain the optimal measurement value of the five groups of impedance measurement values includes: and if the impedance measurement value of the first impedance loop is 1000-5000 omega, the impedance measurement value of the second impedance loop is 200-1000 omega, the impedance measurement value of the third impedance loop is 50-200 omega, the impedance measurement value of the fourth impedance loop is 10-50 omega, and the impedance measurement value of the fifth impedance loop is 5-10 omega, judging that the impedance measurement value is the optimal measurement value.
The system also comprises an FPGA controller, wherein the FPGA is a field programmable logic gate array, and the FPGA controller is used for controlling the running state of each module.
The application discloses a detection system for obtaining thyristor-level impedance of a converter valve, which comprises a test signal generation module, a resistance synchronous measurement module, a voltage and current signal acquisition module and an impedance calculation module; the test signal generation module, the resistance synchronous measurement module, the voltage and current signal acquisition module and the impedance calculation module are sequentially connected; the test signal generation module is used for being connected with a target thyristor-level damping loop and outputting sinusoidal signals with different frequencies to the target thyristor-level damping loop; the resistance synchronous measurement module comprises five reference resistors with different resistance values, and the target thyristor-level damping loop and the five reference resistors with different resistance values form five groups of impedance loops; the voltage circuit signal acquisition module is used for acquiring the voltage and the current of the five groups of impedance loops; the impedance calculation module is used for acquiring impedance measurement values of the five groups of impedance loops according to the voltage and the current of the five groups of impedance loops; and the impedance measurement values of the five groups of impedance loops are compared with the resistance values of the reference resistors of the five groups of impedance loops, so that the optimal measurement value of the five groups of impedance measurement values is obtained, and the module value of the impedance of the target thyristor-level damping loop is obtained.
In order to acquire reliable voltage and current values in a target thyristor-level damping loop, a test signal source can output low-voltage alternating-current signals with different frequencies, the signal frequency can be flexibly set according to the actual situation of an application scene, and the application range is wide; the method and the device adopt the FAGA controller to realize the synchronous measurement of the five high-precision reference resistors with different resistance values, can reduce signal interference and improve the accuracy of impedance measurement values; the method adopts the DSP technology, is convenient for data processing, measures five paths of signals at one time, selects the optimal value to output, and has high processing speed and low power consumption; the method and the device can simultaneously detect the running state of the target thyristor level and help the converter valve to replace the thyristor in time; the impedance of thyristor-level damping loop can be rapidly detected, and the direct-current transmission engineering can be operated safely and stably.
The present application has been described in detail with reference to specific embodiments and illustrative examples, but the description is not intended to limit the application. Those skilled in the art will appreciate that various equivalent substitutions, modifications or improvements may be made to the presently disclosed embodiments and implementations thereof without departing from the spirit and scope of the present disclosure, and these fall within the scope of the present disclosure. The protection scope of this application is subject to the appended claims.
Claims (10)
1. A detection system for obtaining thyristor-level impedance of a converter valve is characterized by comprising a test signal generation module, a resistance synchronous measurement module, a voltage and current signal acquisition module and an impedance calculation module; the test signal generation module, the resistance synchronous measurement module, the voltage and current signal acquisition module and the impedance calculation module are sequentially connected;
the test signal generation module is used for being connected with a target thyristor-level damping loop and outputting sinusoidal signals with different frequencies to the target thyristor-level damping loop;
the resistance synchronous measurement module comprises five reference resistors with different resistance values, and the target thyristor-level damping loop and the five reference resistors with different resistance values form five groups of impedance loops;
the voltage circuit signal acquisition module is used for acquiring the voltage and the current of the five groups of impedance loops and acquiring the voltage and the current of the target thyristor-level damping loop;
the impedance calculation module is used for acquiring impedance measurement values of the five groups of impedance loops according to the voltage and the current of the five groups of impedance loops and the voltage and the current of the target thyristor level damping loop;
the impedance calculation module is further used for comparing the impedance measurement values of the five groups of impedance loops with the resistance values of the reference resistors of the five groups of impedance loops to obtain the optimal measurement value of the five groups of impedance measurement values; and the impedance calculation module is also used for acquiring the module value of the impedance of the target thyristor-level damping loop according to the optimal measurement value.
2. The detecting system for obtaining thyristor-level impedance of a converter valve according to claim 1, wherein the five reference resistors with different resistances have respective resistances of 1000 Ω, 500 Ω, 100 Ω, 20 Ω and 5 Ω, the impedance loop including the 1000 Ω reference resistor in the five groups of impedance loops is a first impedance loop, the impedance loop including the 500 Ω reference resistor is a second impedance loop, the impedance loop including the 100 Ω reference resistor is a third impedance loop, the impedance loop including the 20 Ω reference resistor is a fourth impedance loop, and the impedance loop including the 5 Ω reference resistor is a fifth impedance loop.
3. The detection system for obtaining thyristor-level impedance of a converter valve according to claim 2, wherein the comparing the impedance measurements of the five groups of impedance loops with the resistances of the reference resistors of the five groups of impedance loops to obtain the optimal measurement of the five groups of impedance measurements comprises:
and if the impedance measurement value of the first impedance loop is 1000-5000 omega, the impedance measurement value of the second impedance loop is 200-1000 omega, the impedance measurement value of the third impedance loop is 50-200 omega, the impedance measurement value of the fourth impedance loop is 10-50 omega, and the impedance measurement value of the fifth impedance loop is 5-10 omega, judging that the impedance measurement value is the optimal measurement value.
4. The detection system for obtaining thyristor-level impedance of a converter valve according to claim 1, wherein the test signal generation module comprises an AD9850 direct frequency synthesizer, and the AD9850 direct frequency synthesizer is externally connected with a 125MHz clock.
5. The detection system for obtaining the thyristor-level impedance of the converter valve according to claim 4, wherein the operating voltage of the test signal generation module is 5V, and the output signal is a unipolar analog signal of 0-500 mV.
6. The detection system for obtaining thyristor-level impedance of a converter valve according to claim 1, wherein the resistance synchronous measurement module has a resistance accuracy of 0.1%.
7. The detection system for obtaining the thyristor-level impedance of the converter valve as claimed in claim 1, wherein the voltage-current signal acquisition module comprises two operational amplifiers with non-inverting inputs, and the two operational amplifiers with non-inverting inputs are connected in parallel to form a front-end input stage for increasing the input impedance of the circuit.
8. The detection system for obtaining the thyristor-level impedance of the converter valve according to claim 7, wherein the voltage-current signal acquisition module further comprises a differential operational amplifier, and the front-end input stage and the differential operational amplifier are connected in series to form a three-operational-amplifier differential amplification circuit.
9. The detection system for obtaining thyristor-level impedance of a converter valve as claimed in claim 1, wherein the impedance calculation module employs a DSP chip of a 32-bit processor for controlling data transmission and calculation between the modules.
10. The detection system for obtaining thyristor-level impedance of a converter valve according to claim 1, further comprising an FPGA controller for controlling the operation state of each module.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210355816.0A CN114814512A (en) | 2022-04-06 | 2022-04-06 | Detection system for obtaining thyristor-level impedance of converter valve |
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| CN202210355816.0A CN114814512A (en) | 2022-04-06 | 2022-04-06 | Detection system for obtaining thyristor-level impedance of converter valve |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20050054449A (en) * | 2004-12-01 | 2005-06-10 | 주식회사 파워트론 | Battery cell voltage and impedance measuring circuit |
| CN104808070A (en) * | 2015-04-23 | 2015-07-29 | 许继集团有限公司 | Converter valve thyristor level damping loop parameter testing device and method |
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- 2022-04-06 CN CN202210355816.0A patent/CN114814512A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20050054449A (en) * | 2004-12-01 | 2005-06-10 | 주식회사 파워트론 | Battery cell voltage and impedance measuring circuit |
| CN104808070A (en) * | 2015-04-23 | 2015-07-29 | 许继集团有限公司 | Converter valve thyristor level damping loop parameter testing device and method |
Non-Patent Citations (1)
| Title |
|---|
| 刘隆晨: "直流输电换流阀晶闸管级阻抗测试系统设计", 沈阳工业大学学报, vol. 42, no. 5, 30 September 2020 (2020-09-30), pages 488 - 492 * |
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