A narrow pulse processing structure and its processing method

Abstract

The present invention discloses a narrow pulse processing structure and a processing method thereof. The structure includes: a current signal conversion unit for converting the current detected in the device into a voltage signal; a comparator module connected to the current signal conversion unit, the comparator module compares the voltage value of the voltage signal with a voltage reference value and outputs a corresponding digital signal according to the comparison result; and a logic processing module connected to the comparator module, the logic processing module obtains the current range corresponding to the current according to the digital signal and determines whether the current range is less than the safe turn-off current. The present invention enables the floor board to not need to perform any processing on narrow pulses, reduces the software overhead of the control board, and improves the applicable range of the drive board.

Description

Technical Field

[0001] The present invention belongs to the field of signal processing, and particularly relates to a narrow pulse processing structure and a processing method thereof. Background Art

[0002] The turn-off ability of thyristor-type devices (such as thyristors, integrated gate-commutated thyristors IGCTs, emitter turn-off thyristors ETOs, etc.) is greatly weakened under short conduction signals (commonly known as narrow pulses). If the drive control does not process the narrow pulse signal, the failure probability of thyristor-type devices will increase significantly.

[0003] The existing narrow pulse processing methods are generally of two types. One is to process through a drive board. After the drive board receives the turn-on command from the local board (the full name of the local board is the local control board, which is located near the drive board and communicates with the drive board through optical fibers and can connect to one or more drive boards), it performs the turn-on processing of the thyristor-type device. After that, it shields the received signal from the local board until the conduction time is greater than the minimum time of the narrow pulse and then starts to receive signals again. This processing method has the risk of misjudging the local board failure (the local board sends a turn-off command to the drive board, but the drive board remains in the on state to shield the narrow pulse, and the local board misjudges that the drive board has a turn-off failure). The other is to process through the local board. After the local board receives the turn-on command from the valve control system, it sends a turn-on command to the drive board. After that, it shields the received signal from the valve control system until the conduction time is greater than the minimum time of the narrow pulse and then starts to receive signals again. This processing method has the risk that the thyristor-type device cannot be turned off in time in case of a failure, amplifying the fault current. Summary of the Invention

[0004] In view of the above problems, the present invention provides a narrow pulse processing structure and a processing method thereof to reduce the failure probability of thyristors.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a narrow pulse processing structure, including:

[0006] A current signal conversion unit for converting the current detected in the device into a voltage signal;

[0007] A comparator module connected to the current signal conversion unit. The comparator module compares the voltage value of the voltage signal with a voltage reference value and outputs a corresponding digital signal according to the comparison result; and

[0008] A logic processing module connected to the comparator module. The logic processing module obtains the current interval corresponding to the current according to the digital signal and determines whether the current interval is less than the safe turn-off current.

[0009] Optionally, the current signal conversion unit includes:

[0010] A detection module, configured to detect a current and convert the current into an analog signal;

[0011] A signal conditioning module, connected to the detection module, for converting the analog signal into a voltage signal.

[0012] Optionally, the detection module is a current sensor.

[0013] Optionally, the signal conditioning module includes an operational amplifier.

[0014] Optionally, the comparator module includes a plurality of operational amplifier comparison circuits, and negative input pins of the plurality of operational amplifier comparison circuits are connected to voltages with different reference values, positive input pins are connected to the current signal conversion unit, and output pins are connected to the logic processing module.

[0015] Optionally, voltage reference values accessed by the plurality of operational amplifier comparison circuits gradually increase in sequence and respectively correspond to current reference values, the voltage signal outputs a digital signal through the plurality of operational amplifier comparison circuits, and the logic processing module obtains a corresponding current range by comparing the digital signal with the current reference value.

[0016] Optionally, the processing structure further includes a driving board and a control board connected to the driving board, and the logic processing module is installed on the driving board.

[0017] And, a turn-off circuit, including:

[0018] The above-mentioned narrow pulse processing structure; and

[0019] A thyristor, a cathode of the thyristor is connected to an input end of a current signal processing unit of the narrow pulse processing structure, and an on-module and an off-module are connected in parallel between a gate of the thyristor and the logic processing module of the narrow pulse processing structure.

[0020] And, a narrow pulse processing method, including the following steps:

[0021] Converting a current detected in a device into a voltage signal;

[0022] Comparing the voltage value of the voltage signal with a voltage reference value by using a comparison circuit, and outputting a corresponding digital signal according to a comparison result;

[0023] Obtaining a current range corresponding to the current according to the digital signal;

[0024] Judging whether the current range is less than a safe turn-off current.

[0025] Optionally, in the step of converting a current detected in a device into a voltage signal, specifically:

[0026] Detect the current and convert the current into an analog signal;

[0027] Convert the analog signal into a voltage signal.

[0028] Optionally, the number of the comparison circuits is multiple, and there are multiple voltage reference values with gradually increasing values corresponding thereto. Multiple current reference values respectively correspond to the multiple voltage reference values, and the multiple current reference values with gradually increasing values form multiple current intervals;

[0029] In the steps of outputting a digital signal and obtaining a current interval, specifically:

[0030] Compare the voltage signal with the multiple comparison circuits and output the digital signal;

[0031] Obtain the voltage reference values closest to both ends of the numerical value of the voltage signal according to the digital signal;

[0032] Obtain two corresponding current reference values according to the voltage reference values to form a current interval.

[0033] Optionally, if it is determined that the current interval is less than the safe turn-off current, a turn-off operation is performed;

[0034] If it is determined that the current interval is greater than or equal to the safe turn-off current, delay and wait for the current flowing through the device to enter the safe turn-off current and then perform a turn-off operation.

[0035] Optionally, before the step of converting the current detected in the device into a voltage signal, the following steps are further included:

[0036] The logic processing module receives a turn-off instruction sent by the control board;

[0037] Judge whether the current flowing through the current device is in the narrow pulse stage;

[0038] If it is in the narrow pulse stage, perform voltage signal conversion;

[0039] If it is not in the narrow pulse stage, perform a turn-off operation.

[0040] Due to the adoption of the above technical solutions, the present invention has the following beneficial effects:

[0041] The floor does not need to perform any processing on the narrow pulse, reducing the software overhead of the control board and improving the applicable range of the drive board;

[0042] In case of a fault, the drive board can be maximally protected from the influence of narrow pulses, timely turned off, and the failure probability of the thyristor is reduced. Description of the Drawings

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings.

[0044] Figure 1 A structural block diagram of a narrow pulse processing structure according to an embodiment of the present invention is shown;

[0045] Figure 2 A schematic diagram showing the relationship between the current passing through the device currently and the digital signal according to an embodiment of the present invention is shown;

[0046] Figure 3 A logic diagram of the turn-off processing according to an embodiment of the present invention is shown. Detailed implementation manners

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0048] As Figure 1 shown, the narrow pulse processing structure of the embodiment of the present invention includes a current signal conversion unit, a comparator module, and a logic processing module. Among them, the current signal conversion unit is used to convert the detected current in the device into a voltage signal; the comparator module is connected to the current signal conversion unit, and the comparator module compares the voltage value of the voltage signal with a voltage reference value and outputs a corresponding digital signal according to the comparison result; the logic processing module is connected to the comparator module, and the logic processing module obtains the current range corresponding to the current according to the digital signal and determines whether the current range is less than the safe turn-off current.

[0049] Based on the narrow pulse processing structure of the above embodiment of the present invention, the narrow pulse processing method of the embodiment of the present invention is further introduced, including the following steps:

[0050] S1: Convert the detected current in the device into a voltage signal;

[0051] In this embodiment, specifically, a current signal conversion unit is used to convert the detected current in the device into a voltage signal.

[0052] S2: Compare the voltage value of the voltage signal with a voltage reference value using a comparison circuit, and output a corresponding digital signal according to the comparison result;

[0053] S3: Obtain the current range corresponding to the current according to the digital signal;

[0054] S4: Determine whether the current range is less than the safe turn-off current.

[0055] Furthermore, the narrow pulse processing structure of the embodiment of the present invention can act on a turn-off circuit, such as Figure 1 shown. The turn-off circuit includes the narrow pulse processing structure and a thyristor GCT. Among them, the cathode of the thyristor GCT is connected to the input end of the current signal processing unit of the narrow pulse processing structure, and an on-module and an off-module are connected in parallel between the gate of the thyristor GCT and the logic processing module of the narrow pulse processing structure.

[0056] In this embodiment, the current signal conversion unit includes a detection module and a signal conditioning module. The detection module is used to detect the current and convert the current into an analog signal. The signal conditioning module is connected to the detection module and is used to convert the analog signal into a voltage signal. Among them, the detection module is a current sensor, and the signal conditioning module includes an operational amplifier.

[0057] Based on the above, in step S1 of the narrow pulse processing method of the embodiment of the present invention, specifically:

[0058] S11: The current sensor detects the current between the anode and the cathode of the thyristor-type device and converts the current into a weak analog signal;

[0059] S12: Convert the analog signal into a unipolar appropriate voltage signal through the operational amplifier of the signal conditioning module and send it to the comparator module.

[0060] Preferably, the comparator module includes a plurality of operational amplifier comparison circuits, and the negative input pins of the plurality of operational amplifier comparison circuits are connected to voltages with different reference values. The positive input pins are connected to the current signal conversion unit, and the output pins are connected to the logic processing module. The voltage reference values accessed by the plurality of operational amplifier comparison circuits increase gradually in sequence and respectively correspond to current reference values. The voltage signal outputs a digital signal through the plurality of operational amplifier comparison circuits, and the logic processing module obtains the corresponding current range by comparing the digital signal with the current reference value.

[0061] In this embodiment, as Figure 1As shown, six operational amplifier comparison circuits are selected as S1, S2, S3, S4, S5, and S6, and the voltage reference values connected to the negative pins of the six operational amplifier comparison circuits are VOCP1, VOCP2, VOCP3, VOCP4, VOCP5, and VOCP6 respectively, and the values of VOCP1, VOCP2, VOCP3, VOCP4, VOCP5, and VOCP6 increase gradually. The corresponding current reference values are Iocp1, Iocp2, Iocp3, Iocp4, Iocp5, and Iocp6 respectively. The digital signal is set as [S6..S1].

[0062] Combined with Figure 2 As shown, when the voltage signal V > VOCP6, the digital signal [S6..S1] = "111111"; when VOCP5 < V ≤ VOCP6, [S6..S1] = "011111"; when VOCP4 < V ≤ VOCP5, [S6..S1] = "001111"; when VOCP3 < V ≤ VOCP4, [S6..S1] = "000111"; when VOCP2 < V ≤ VOCP3, [S6..S1] = "000011"; when VOCP1 < V ≤ VOCP2, [S6..S1] = "000001"; when V ≤ VOCP1, [S6..S1] = "000000".

[0063] As can be seen from the above, when the digital signal [S6..S1] = "111111", the current I flowing through the corresponding thyristor device GCT is I > Iocp6; when [S6..S1] = "011111", Iocp5 < I ≤ Iocp6; when [S6..S1] = "001111", Iocp4 < I ≤ Iocp5; when [S6..S1] = "000111", Iocp3 < I ≤ Iocp4; when [S6..S1] = "000011", Iocp2 < I ≤ Iocp3; when [S6..S1] = "000001", Iocp1 < I ≤ Iocp2; when [S6..S1] = "000000", I ≤ Iocp1. Thus, according to the output digital signal, the current range corresponding to the digital signal can be obtained through the logic processing module.

[0064] It should be noted that in some other embodiments, those skilled in the art can adjust the number of operational amplifier comparison circuits and the magnitude of the voltage reference values connected according to actual needs.

[0065] Based on the above, in steps S2 and S3 of the narrow pulse processing method according to the embodiment of the present invention, specifically:[[]]

[0066] S31: Compare the voltage signal with multiple voltage reference values through an operational amplifier comparator and output the digital signal;

[0067] S32: Obtain voltage reference values closest to both ends of the magnitude of the voltage signal according to the digital signal;

[0068] S33: Obtain two corresponding current reference values according to the voltage reference values to form a current range.

[0069] The processing structure further includes a drive board and a control board connected to the drive board, and the logic processing module is installed on the drive board. In this embodiment, the control board is a local control board (hereinafter referred to as the local board), the local board is located near the drive board, and communicates with the drive board through optical fiber. Its main functions are: one is to send a turn-off instruction to the drive board, and the other is to process the fault signal returned by the logic processing module in the drive board.

[0070] Before step S1 of the narrow pulse processing method in the embodiment of the present invention, the following steps are further included:

[0071] S01: The logic processing module receives the turn-off instruction sent by the local board;

[0072] S02: Judge whether the current flowing through the current device is in the narrow pulse stage. Among them, if it is in the narrow pulse stage, perform the above steps S1 to S4; if it is not in the narrow pulse stage, perform a turn-off operation through the drive board.

[0073] Specifically, judge whether it is in the narrow pulse stage by the device turn-on time, combined with Figure 3 As shown, it belongs to the narrow pulse stage before time t2.

[0074] After step S4 of the narrow pulse processing method in the embodiment of the present invention, the following steps are further included:

[0075] S51: If it is judged that the current range is less than the safe turn-off current, control the turn-off module through the drive board to perform a turn-off operation;

[0076] S52: If it is judged that the current range is greater than or equal to the safe turn-off current, delay and wait for the current flowing through the device to enter the safe turn-off current before performing a turn-off operation.

[0077] Combined with Figure 3Schematic diagram of the turn-off processing logic shown. The principle is as follows: The solid-line filled area is the device's safe turn-off current range, and the dashed line is the actual current flowing through the device. Among them, t0 to t2 is the narrow pulse stage. When the device receives a turn-off command during the time period from t0 to t1, since the actual current of the device is less than the safe turn-off current at this time, it cannot be turned off immediately and needs to be delayed until t1 before it can be turned off; when the device receives a turn-off command during the time period from t1 to t2, since the actual current of the device is greater than the safe turn-off current at this time, a turn-off operation can be performed; when the device receives a turn-off command during the time period after t2, since it is not in the narrow pulse stage at this time, the device is immediately turned off.

[0078] Through the above solution, the local board does not need to perform any processing on narrow pulses, reducing the software overhead of the local board and increasing the applicable range of the drive board; in case of a fault, the drive board can be maximally protected from the influence of narrow pulses and can be turned off in time, reducing the failure probability of the thyristor GCT.

[0079] It should be noted that in the technical solution of the present invention, S1, S2, S3... are used to represent the execution steps, but it does not mean that S2 must be executed after S1, and it does not exclude that there are other steps executed in S1 and S2.

[0080] The above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art, without departing from the technical solution of the present invention, can make some changes or modifications to equivalent embodiments by using the disclosed technical content. However, as long as it does not depart from the technical content of the present invention, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A narrow pulse processing structure, characterized in that, Comprising: A current signal conversion unit for converting a narrow pulse current detected in a device into a voltage signal; A comparator module connected to the current signal conversion unit. The comparator module compares the voltage values at both ends of the voltage signal with a voltage reference value respectively and outputs a corresponding digital signal according to the comparison result. The comparator module includes a plurality of operational amplifier comparison circuits, and the negative input pins of the plurality of operational amplifier comparison circuits are connected to voltages with different reference values, the positive input pins are connected to the current signal conversion unit, and the output pins are connected to a logic processing module. The voltage reference values accessed by the plurality of operational amplifier comparison circuits increase gradually in sequence and each corresponds to a current reference value. The voltage signal outputs a digital signal through the plurality of operational amplifier comparison circuits; And A logic processing module connected to the comparator module. The logic processing module obtains the current range corresponding to the narrow pulse current by comparing the digital signal with the current reference value and determines whether the current range is less than the safe turn-off current.

2. The narrow pulse processing structure according to claim 1, wherein, The current signal conversion unit includes: A detection module for detecting current and converting the narrow pulse current into an analog signal; A signal conditioning module connected to the detection module for converting the analog signal into the voltage signal.

3. The narrow pulse processing structure according to claim 2, wherein The detection module is a current sensor.

4. The narrow pulse processing structure according to claim 2, wherein The signal conditioning module includes an operational amplifier.

5. The narrow pulse processing structure according to claim 1, characterized in that, The processing structure further includes a drive board and a control board connected to the drive board, and the logic processing module is installed on the drive board.

6. A turn-off circuit, characterized in that, Comprising: The narrow pulse processing structure according to any one of claims 1-5; And A thyristor, the cathode of the thyristor is connected to the input end of the current signal processing unit of the narrow pulse processing structure, and an on-module and an off-module are connected in parallel between the gate of the thyristor and the logic processing module of the narrow pulse processing structure.

7. A narrow pulse processing method, characterized in that, Including the following steps: Converting the narrow pulse current detected in the device into a voltage signal, including: detecting the narrow pulse current and converting the narrow pulse current into an analog signal, and converting the analog signal into a voltage signal; Respectively comparing the voltage values at both ends of the voltage signal with a voltage reference value by using a comparison circuit according to the comparison result and outputting a corresponding digital signal; Obtaining the current range corresponding to the narrow pulse current according to the digital signal; the number of the comparison circuits is multiple and corresponds to multiple voltage reference values with gradually increasing values. Among them, the voltage signal is compared with multiple comparison circuits and the digital signal is output. According to the digital signal, the voltage reference values closest to the voltage values at both ends of the voltage signal are obtained respectively. According to the voltage reference values, two corresponding current reference values are obtained to form a current range; Judging whether the current range is less than the safe turn-off current.

8. The narrow pulse processing method according to claim 7, characterized in that, The multiple voltage reference values respectively correspond to current reference values, and the multiple current reference values with gradually increasing values form multiple current ranges.

9. The narrow pulse processing method according to claim 7, characterized in that If it is judged that the current range is less than the safe turn-off current, a turn-off operation is performed; If it is determined that the current range is greater than or equal to the safe turn-off current, then delay and wait for the current flowing through the device to enter the safe turn-off current before performing the turn-off operation.

10. The narrow pulse processing method according to claim 7, wherein Before the step of converting the current detected in the device into a voltage signal, the following steps are further included: The logic processing module receives the turn-off instruction sent by the control board; Judge whether the current flowing through the current device is in the narrow pulse stage; If it is in the narrow pulse stage, then perform voltage signal conversion; If it is not in the narrow pulse stage, then perform the turn-off operation.

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