Contactless AC Voltage Regulator Silicon Controlled Rectifier Damage Detection Circuit

Abstract

This application relates to a thyristor damage detection circuit for a contactless AC voltage regulator, including: a circuit detection sensor, a controller, a transformer, and a triac group. Among them, the circuit detection sensor and the transformer are connected to the live wire, the circuit detection sensor is also connected to the controller, and the triac group is connected to the neutral wire and the transformer. During implementation, the circuit detection sensor detects the positive half-cycle current and the negative half-cycle current in the circuit, and sends the positive half-cycle current and the negative half-cycle current to the controller. When any one-way thyristor in the path of the positive half-cycle current or the negative half-cycle current is damaged, the current in that half-cycle will be 0. If there is no damage, the values of the positive half-cycle current and the negative half-cycle current are equal. Based on this, the controller can determine whether the triac group is damaged and output a judgment result.

Description

Technical Field

[0001] This application relates to the technical field of circuit fault detection, and particularly to a contactless AC voltage regulator thyristor damage detection circuit. Background Art

[0002] Contactless AC voltage regulators have gradually matured in recent years. Existing contactless AC voltage regulators mostly use bidirectional thyristors as bidirectional switches. A bidirectional thyristor includes two reverse unidirectional thyristor switches. If one of them is damaged, it will cause the circuit to conduct in single phase, generating a DC current. The harm of DC current in an AC circuit is great and can cause the transformer to burn out. However, it is difficult to detect faults and damages in the thyristor control circuit in the prior art. Summary of the Invention

[0003] To overcome at least to some extent the problem in the related art that it is difficult to detect faults and damages in the thyristor control circuit, this application provides a contactless AC voltage regulator thyristor damage detection circuit.

[0004] The solution of this application is as follows:

[0005] A contactless AC voltage regulator thyristor damage detection circuit includes:

[0006] A circuit detection sensor, a controller, a transformer, and a bidirectional thyristor group;

[0007] The circuit detection sensor and the transformer are connected to the live wire;

[0008] The circuit detection sensor is also connected to the controller;

[0009] The bidirectional thyristor group is connected to the neutral wire and the transformer;

[0010] The circuit detection sensor is used to detect the positive half-cycle current and the negative half-cycle current in the circuit, and send the positive half-cycle current and the negative half-cycle current to the controller;

[0011] The controller is used to judge whether the bidirectional thyristor group is damaged according to the positive half-cycle current and the negative half-cycle current, and output a judgment result.

[0012] Preferably, the bidirectional thyristor group includes a first bidirectional thyristor group and a second bidirectional thyristor group;

[0013] The first bidirectional thyristor group includes at least one first bidirectional thyristor;

[0014] The second bidirectional thyristor group includes at least one second bidirectional thyristor;

[0015] Each of the first bidirectional thyristors and each of the second bidirectional thyristors corresponds one by one.

[0016] Preferably, the transformer includes a secondary winding and a primary winding;

[0017] Each of the first triacs is connected to the secondary winding and the primary winding;

[0018] Each of the second triacs is connected to the primary winding and the neutral line.

[0019] Preferably, each of the first triacs includes a first thyristor and a second thyristor; each of the second triacs includes a third thyristor and a fourth thyristor.

[0020] Preferably, the two thyristor switches in the same triac are synchronized.

[0021] Preferably, the path of the positive half-cycle current includes: the input end of the live wire, the circuit detection sensor, the secondary winding, each of the first thyristors, the primary winding, each of the third thyristors, and the output end of the neutral line;

[0022] The path of the negative half-cycle current includes: the input end of the neutral line, each of the fourth thyristors, the primary winding, each of the second thyristors, the secondary winding, the circuit detection sensor, and the output end of the live wire.

[0023] Preferably, it further includes: a fuse;

[0024] The secondary winding is connected to each of the first triacs through the fuse.

[0025] Preferably, it further includes: an air switch;

[0026] The air switch is respectively connected to the live wire and the controller;

[0027] The controller is configured to determine that the triac group is damaged when the difference between the positive half-cycle current and the negative half-cycle current is greater than a preset threshold, and control the air switch to disconnect.

[0028] The technical solution provided by this application may include the following beneficial effects: The thyristor damage detection circuit of the contactless AC voltage regulator in this application includes: a circuit detection sensor, a controller, a transformer, and a bidirectional thyristor group. Among them, the circuit detection sensor and the transformer are connected to the live wire, the circuit detection sensor is also connected to the controller, and the bidirectional thyristor group is connected to the neutral wire and the transformer. During implementation, the circuit detection sensor detects the positive half-cycle current and the negative half-cycle current in the circuit, and sends the positive half-cycle current and the negative half-cycle current to the controller. When any one-way thyristor in the path of the positive half-cycle current or the negative half-cycle current is damaged, the half-cycle current will be 0. If there is no damage, the positive half-cycle current and the negative half-cycle current have equal values. Based on this, the controller can determine whether the bidirectional thyristor group is damaged and output a judgment result.

[0029] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit this application. Brief Description of the Drawings

[0030] The drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application.

[0031] Figure 1 is a schematic diagram of a thyristor damage detection circuit of a contactless AC voltage regulator provided by an embodiment of this application;

[0032] Figure 2 is a schematic diagram of a thyristor damage detection circuit of a contactless AC voltage regulator provided by another embodiment of this application;

[0033] Figure 3 is a schematic diagram of the current path of the positive half-cycle current in a thyristor damage detection circuit of a contactless AC voltage regulator provided by an embodiment of this application;

[0034] Figure 4 is a schematic diagram of the current path of the negative half-cycle current in a thyristor damage detection circuit of a contactless AC voltage regulator provided by an embodiment of this application;

[0035] Figure 5 is a schematic diagram of the current signal detected by a circuit detection sensor provided by an embodiment of this application;

[0036] Figure 6 is a schematic diagram of a thyristor damage detection circuit of a contactless AC voltage regulator provided by another embodiment of this application.

[0037] Reference Numerals: Circuit detection sensor - 1; Controller - 2; Transformer - 3; Secondary winding - 31; Primary winding - 32; Triac group - 4; First triac group - 41; Second triac group - 42; Fuse - 5; Air switch - 6; First unilateral thyristor - S1; Second unilateral thyristor - S2; Third unilateral thyristor - S3; Fourth unilateral thyristor - S4. Detailed Implementation Manner

[0038] Here, exemplary embodiments will be described in detail, and the examples are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0039] Embodiment 1

[0040] Figure 1 It is a schematic diagram of a thyristor damage detection circuit for a contactless AC voltage stabilizer provided by an embodiment of the present application. Refer to Figure 1 , A thyristor damage detection circuit for a contactless AC voltage stabilizer includes:

[0041] A circuit detection sensor 1, a controller 2, a transformer 3, and a triac group 4;

[0042] The circuit detection sensor 1 and the transformer 3 are connected to the live wire;

[0043] The circuit detection sensor 1 is also connected to the controller 2;

[0044] The triac group 4 is connected to the neutral wire and the transformer 3;

[0045] The circuit detection sensor 1 is used to detect the positive - half - cycle current and the negative - half - cycle current in the circuit, and send the positive - half - cycle current and the negative - half - cycle current to the controller 2;

[0046] The controller 2 is used to judge whether the triac group 4 is damaged according to the positive - half - cycle current and the negative - half - cycle current, and output the judgment result.

[0047] It should be noted that, refer to Figure 2 , The triac group 4 includes a first triac group 41 and a second triac group 42;

[0048] The first triac group 41 includes at least one first triac;

[0049] The second triac group 42 includes at least one second triac;

[0050] Each first triac and each second triac correspond to each other one by one.

[0051] It can be understood that the number of triacs in the triac group 4 in this embodiment is an integer multiple of 2. That is, specifically in implementation, the triac group 4 may include 2, 4, 6, 8, 10... triacs. Since the triacs in the triac group 4 have a one-to-one correspondence, the triacs in the triac group 4 are divided into a first triac group 41 and a second triac group 42 in this embodiment. The first triacs in the first triac group 41 and the second triacs in the second triac group 42 correspond to each other one by one.

[0052] It should be noted that referring to Figure 2 , the transformer 3 includes a secondary winding 31 and a primary winding 32;

[0053] Each first triac is connected to both the secondary winding 31 and the primary winding 32;

[0054] Each second triac is connected to both the primary winding 32 and the neutral line.

[0055] It can be understood that the first triac and the second triac with a corresponding relationship are connected through the primary winding 32.

[0056] It should be noted that referring to Figure 3 or Figure 4 , each first triac includes a first single-phase thyristor S1 and a second single-phase thyristor S2; each second triac includes a third single-phase thyristor S3 and a fourth single-phase thyristor S4.

[0057] Specifically in implementation, the two single-phase thyristor switches in the same triac are synchronized. That is, the two single-phase thyristor switches in the same triac are used as a group of AC bidirectional switches. The two single-phase thyristor switches in the same triac must be given open and close signals simultaneously.

[0058] Figure 3 and Figure 4 are schematic diagrams of the current paths in a group of a first triac and a second triac with a corresponding relationship. As Figure 3 shown by the arrow, the path of the positive half-cycle current includes: the input end of the live wire, the circuit detection sensor 1, the secondary winding 31, the first single-phase thyristor S1, the primary winding 32, the third single-phase thyristor S3, and the output end of the neutral line; as Figure 4 shown by the arrow, the path of the negative half-cycle current includes: the input end of the neutral line, the fourth single-phase thyristor S4, the primary winding 32, the second single-phase thyristor S2, the secondary winding 31, the circuit detection sensor 1, and the output end of the live wire.

[0059] It can be understood that the path of the positive half-cycle current is: the input end of the live wire → the circuit detection sensor 1 → the secondary winding 31 → each first one-way thyristor S1 → the primary winding 32 → each third one-way thyristor S3 → the output end of the neutral wire. The path of the negative half-cycle current is: the input end of the neutral wire → the fourth one-way thyristor S4 → the primary winding 32 → the second one-way thyristor S2 → the secondary winding 31 → the circuit detection sensor 1 → the output end of the live wire.

[0060] It can be understood that the current paths of other corresponding first bidirectional thyristors and second bidirectional thyristors are the same as the above examples and will not be elaborated here.

[0061] It can be understood that the circuit detection sensor 1 is connected in series in the circuit to detect the positive half-cycle current and negative half-cycle current in the circuit and send them to the controller 2.

[0062] It should be noted that the current signal detected by the circuit detection sensor 1 is as Figure 5 shown, and the controller 2 calculates the positive half-cycle current and negative half-cycle current respectively through ADC sampling.

[0063] When any one-way thyristor in the path of the positive half-cycle current or negative half-cycle current is damaged, the current of that half-cycle will be 0. For example, Figure 3 if the first one-way thyristor S1S1 in [figure] is damaged, the positive half-cycle current will be 0. Figure 4 if the second one-way thyristor S2S2 in [figure] is damaged, the negative half-cycle current will be 0. If neither is damaged, the values of the positive half-cycle current and negative half-cycle current are equal. Based on this, the controller 2 can determine whether the bidirectional thyristor group 4 is damaged and output the judgment result.

[0064] Embodiment 2

[0065] The contactless AC voltage regulator thyristor damage detection circuit in this embodiment, referring to Figure 6 also includes: a fuse 5;

[0066] The secondary winding 31 is connected to each first bidirectional thyristor through the fuse 5.

[0067] It can be understood that in this embodiment, by setting the fuse 5, the secondary winding 31 is connected to each first bidirectional thyristor through the fuse 5. When a circuit fault or abnormality occurs, along with the continuous increase of the current, the fuse 5 will melt and cut off the current by itself when the current abnormally rises to a certain height and at a certain time, preventing the increased current from damaging the devices in the circuit, burning out the circuit or even causing a fire, playing a role in protecting the safe operation of the circuit.

[0068] Embodiment 3

[0069] The thyristor damage detection circuit of the contactless AC voltage regulator in this embodiment further includes: an air switch 6;

[0070] The air switch 6 is respectively connected to the live wire and the controller 2;

[0071] The controller 2 is configured to determine that the bidirectional thyristor group 4 is damaged when the difference between the positive half-cycle current and the negative half-cycle current is greater than a preset threshold, and control the air switch 6 to disconnect.

[0072] It can be understood that due to the influence of some external factors, even when the circuit is not damaged, there may be some errors in the obtained positive half-cycle current and negative half-cycle current. In this embodiment, a certain allowable error threshold such as 0.1A can be set. When the difference between the positive half-cycle current and the negative half-cycle current is not greater than 0.1A, it is determined that the bidirectional thyristor group 4 is not damaged. When the difference between the positive half-cycle current and the negative half-cycle current is greater than 0.1A, it is determined that the bidirectional thyristor group 4 is damaged.

[0073] It can be understood that in this embodiment, by setting the air switch 6, the air switch 6 is respectively connected to the live wire and the controller 2. When the difference between the positive half-cycle current and the negative half-cycle current is greater than the preset threshold, the controller 2 determines that the bidirectional thyristor group 4 is damaged and directly controls the air switch 6 to disconnect to cut off the current, preventing the increased current from damaging the devices in the circuit, burning out the circuit or even causing a fire, thus playing a role in protecting the safe operation of the circuit.

[0074] It can be understood that the same or similar parts in the above embodiments can be referred to each other. For the content not detailed in some embodiments, reference can be made to the same or similar content in other embodiments.

[0075] It should be noted that in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" refers to at least two.

[0076] Any process or method description shown in the flowchart or described in other ways herein can be understood as representing a module, segment, or part of executable instructions including one or more steps for implementing a specific logical function or process. The scope of the preferred embodiments of this application includes additional implementations, where the functions can be executed in a manner that is not shown or discussed in the order, including in a substantially simultaneous manner according to the functions involved or in the reverse order, which should be understood by those skilled in the technical field to which the embodiments of this application belong.

[0077] It should be understood that each part of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), and the like.

[0078] Those of ordinary skill in the art can understand that all or part of the steps carried by the method of the above embodiments can be completed by instructing relevant hardware through a program. The program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0079] In addition, in each embodiment of the present application, each functional unit can be integrated into a processing module, or each unit can exist physically alone, or two or more units can be integrated into a module. The above integrated module can be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0080] The above-mentioned storage medium can be a read-only memory, a magnetic disk, an optical disk, or the like.

[0081] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0082] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application.

Claims

1. A thyristor damage detection circuit for a contactless AC voltage stabilizer, characterized in that, Including: A circuit detection sensor, a controller, a transformer, and a triac group; The circuit detection sensor and the transformer are connected to the live wire; The circuit detection sensor is also connected to the controller; The triac group is connected to the neutral wire and the transformer; The circuit detection sensor is used to detect the positive half-cycle current and the negative half-cycle current in the circuit, and send the positive half-cycle current and the negative half-cycle current to the controller; The controller is used to judge whether the triac group is damaged according to the positive half-cycle current and the negative half-cycle current, and output a judgment result; The triac group includes a first triac group and a second triac group; The first triac group includes at least one first triac; The second triac group includes at least one second triac; Each of the first triacs and each of the second triacs corresponds one by one; The transformer includes a secondary winding and a primary winding; Each of the first triacs is connected to the secondary winding and the primary winding; Each of the second triacs is connected to the primary winding and the neutral wire.

2. The circuit according to claim 1, wherein Each of the first triacs includes a first unidirectional thyristor and a second unidirectional thyristor; each of the second triacs includes a third unidirectional thyristor and a fourth unidirectional thyristor.

3. The circuit according to claim 2, wherein The two unidirectional thyristor switches in the same triac are synchronized.

4. The circuit according to claim 2, wherein The path of the positive half-cycle current includes: the input end of the live wire, the circuit detection sensor, the secondary winding, each first unidirectional thyristor, the primary winding, each third unidirectional thyristor, and the output end of the neutral wire; The path of the negative half-cycle current includes: the input end of the neutral wire, each fourth unidirectional thyristor, the primary winding, each second unidirectional thyristor, the secondary winding, the circuit detection sensor, and the output end of the live wire.

5. The circuit according to claim 1, characterized in that Also including: A fuse; The secondary winding is connected to each of the first triacs through the fuse.

6. The circuit according to claim 1, wherein Also including: An air switch; The air switch is respectively connected to the live wire and the controller; The controller is used to judge that the triac group is damaged when the difference between the positive half-cycle current and the negative half-cycle current is greater than a preset threshold, and control the air switch to disconnect.

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