A dry-type transformer load self-diagnosis protection device

Abstract

The present invention discloses a dry-type transformer load self-diagnosis protection device, including a transformer body, an iron core and a winding wound on the iron core, and the self-diagnosis protection device also includes a normally closed temperature switch and an AC contactor. The normally closed temperature switch is provided with a temperature sensor and is connected in series with the winding. The AC contactor is connected in series with the input control or output control end of the winding and is electrically connected to the normally closed temperature switch. The normally open / normally closed conversion of the normally closed temperature switch is used as the signal given medium of the AC contactor, and the temperature of the winding is monitored in real time. A detection circuit detects the abnormality of the signal and directly controls the on and off of the AC contactor. The self-diagnosis protection device of the present invention can self-diagnose whether the transformer itself has an excessively high operating temperature or an excessively large load, thereby disconnecting the power supply on the input side or the output side for the purpose of self-protection and back-end power protection.

Description

Technical Field

[0001] The invention relates to the technical field of dry-type transformers, in particular to a dry-type transformer load self-diagnosis protection device. Background Art

[0002] At present, dry-type transformers without external protection control used in many industries such as automation control, intelligent mechanical equipment and low-voltage power distribution are all uncontrolled power supplies.

[0003] Power frequency low voltage dry-type transformers are divided into self-coupling dry-type transformers and isolation dry-type transformers according to the principle of electromagnetic coupling. According to the electrical power supply structure, they are divided into single-phase dry-type transformers and three-phase dry-type transformers. Self-coupling dry-type transformers, isolation dry-type transformers, single-phase dry-type transformers and three-phase dry-type transformers are all composed of coil windings and silicon rigid magnets.

[0004] The uncontrolled application of dry-type transformers is very risky. Generally speaking, there are many cases where the transformer is damaged due to the voltage on the power supply input side deviating from the rated input voltage level or the load end being greater than the transformer's own capacity for a long time. What is more serious is that it causes damage and abnormality to the load's back-end equipment.

[0005] Therefore, it is necessary to set a protective device on the dry-type transformer to solve the above technical problems. Summary of the invention

[0006] In view of the deficiencies in the prior art, the technical problem to be solved by the present invention is to provide a dry-type transformer load self-diagnosis protection device. The purpose of designing the dry-type transformer load self-diagnosis protection device is to solve the hidden dangers caused by human or non-human factors changing the electrical environment and electricity quality during the use of the transformer.

[0007] In order to solve the above technical problems, the present invention is implemented by the following scheme: A dry-type transformer load self-diagnosis protection device of the present invention includes a transformer body, wherein the transformer body is provided with an iron core and a winding wound on the iron core, and the self-diagnosis protection device also includes:

[0008] a resettable normally closed temperature switch installed on the transformer body, on which a temperature sensor is provided, and the normally closed temperature switch is connected in series with the winding;

[0009] An external AC contactor is connected in series to the input control or output control end of the winding and is electrically connected to the normally closed temperature switch. The normally open / normally closed conversion of the normally closed temperature switch is used as the signal given medium of the AC contactor, thereby monitoring the temperature of the winding in real time. A detection circuit directly controls the on and off of the AC contactor when detecting abnormality of the signal.

[0010] Furthermore, when the transformer body is a single-phase transformer and the rated current is less than 20A, the installation structure of the protection device is:

[0011] A single-phase primary winding, a single-phase secondary winding and an insulating layer are provided on the iron core. The normally closed temperature switch is fixed when the inter-turn insulating layer is wound. The normally closed temperature switch is connected in series with the single-phase primary winding, and its suspended end serves as the input end of the single-phase transformer, wherein the iron core is grounded.

[0012] Furthermore, when the transformer body is a single-phase auto-coupled transformer and the rated current is less than 20A, the installation structure of the protection device is:

[0013] The iron core is provided with a single-phase primary winding, a single-phase secondary winding and an insulating layer, the normally closed temperature switch is fixed to the single-phase secondary winding and fixed through the insulating layer, the normally closed temperature switch is connected in series with the single-phase secondary winding, wherein the iron core is grounded.

[0014] Furthermore, when the transformer body is a three-phase transformer and the rated current is greater than 20A, the installation structure of the protection device is:

[0015] A three-phase primary winding, a three-phase secondary winding and an insulating layer are provided on the iron core. The normally closed temperature switch is fixed in the insulating layer. The normally closed temperature switch has three groups and correspondingly fixed to the three windings of the three-phase secondary winding. The three groups of normally closed temperature switches are connected in series, and the two lead wires after the series connection are connected to the coil signal control point of the AC contactor.

[0016] Furthermore, a heat dissipation channel is provided on the three-phase transformer.

[0017] Furthermore, when the transformer body is a three-phase auto-coupling transformer and the rated current is greater than 20A, the installation structure of the protection device is:

[0018] A three-phase primary winding, a three-phase secondary winding and an insulating layer are provided on the iron core. The normally closed temperature switch is fixed in the insulating layer. The normally closed temperature switch has three groups and correspondingly fixed to the three windings of the three-phase secondary winding. The three groups of normally closed temperature switches are connected in series, and the two lead wires after the series connection are connected to the coil signal control point of the AC contactor.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: the self-diagnosis protection device of the present invention is based on the reality that the load environment of single-phase and three-phase dry-type transformers is changeable and uncontrolled, and can self-diagnose whether the transformer itself has an excessively high operating temperature or an excessively large load, thereby disconnecting the power supply on the input side or the output side for the purpose of self-protection and back-end power protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the structure of a single-phase primary winding of a single-phase transformer in Embodiment 2 of the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of a single-phase transformer after a normally closed temperature switch is installed in Example 2 of the present invention.

[0022] Figure 3 This is a schematic diagram of the electrical structure of the single-phase transformer after installation in Example 2 of the present invention.

[0023] Figure 4 This is a schematic diagram of the structure of the single-phase auto-coupled transformer after installation in Example 3 of the present invention.

[0024] Figure 5 It is a schematic diagram of the structure of the three-phase primary coil wound on the three-phase transformer in Embodiment 4 of the present invention.

[0025] Figure 6 This is a schematic diagram of the structure of a three-phase transformer after a normally closed temperature switch is installed in Example 4 of the present invention.

[0026] Figure 7 This is a schematic diagram of the structure of the AC contactor connected after the three-phase transformer is installed in Example 4 of the present invention.

[0027] Figure 8 This is a schematic diagram of the structure of the three-phase auto-coupled transformer after installation in Example 5 of the present invention. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention, so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the protection scope of the present invention. Obviously, the embodiments described in the present invention are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0029] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can also be the internal connection of two components, it can be a wireless connection, or it can be a wired connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0032] In order to solve the problems in the prior art, the protection measure developed by the present invention is to perform real-time temperature monitoring on the winding and diagnose the working state of the transformer based on its working temperature.

[0033] Embodiment 1, the specific structure of the present invention is as follows:

[0034] A dry-type transformer load self-diagnosis protection device comprises a transformer body, wherein an iron core and a winding 1 wound on the iron core are arranged in the transformer body, and the self-diagnosis protection device further comprises:

[0035] A resettable normally closed temperature switch 2 installed on the transformer body, on which a temperature sensor is provided, and the normally closed temperature switch 2 is connected in series with the winding;

[0036] An external AC contactor is connected in series to the input control or output control end of the winding and is electrically connected to the normally closed temperature switch 2. The normally open / normally closed conversion of the normally closed temperature switch 2 is used as the signal given medium of the AC contactor, thereby monitoring the temperature of the winding in real time. A detection circuit detects the abnormality of the signal and directly controls the on and off of the AC contactor.

[0037] Embodiment 2:

[0038] like Figure 1-3 As shown, when the transformer body is a single-phase transformer and the rated current is less than 20A, the installation structure of the protection device is:

[0039] The iron core is provided with a single-phase primary winding, a single-phase secondary winding and an insulating layer. The normally closed temperature switch 2 is fixed when the inter-turn insulating layer is wound. The normally closed temperature switch 2 is connected in series with the single-phase primary winding, and its suspended end serves as the input end of the single-phase transformer, wherein the iron core is grounded.

[0040] The specific steps for installing a single-phase transformer are as follows:

[0041] Step 1: After winding the single-phase primary winding, stop. Figure 1 As shown;

[0042] Step 2: Wind the inter-turn insulation layer and fix the normally closed temperature switch 2, such as Figure 2 As shown;

[0043] Step 3, wind the insulation layer again, and then wind the single-phase secondary winding;

[0044] Step 4: After the single-phase transformer is assembled, the normally closed temperature switch 2 is connected in series to the single-phase primary winding, and the floating end is used as the input end of the single-phase transformer. Figure 3 shown.

[0045] Embodiment 3:

[0046] like Figure 4 As shown, when the transformer body is a single-phase auto-coupling transformer and the rated current is less than 20A, the installation structure of the protection device is:

[0047] The iron core is provided with a single-phase primary winding, a single-phase secondary winding and an insulating layer, the normally closed temperature switch 2 is fixed to the single-phase secondary winding and fixed through the insulating layer, the normally closed temperature switch 2 is connected in series with the single-phase secondary winding, wherein the iron core is grounded.

[0048] The assembly steps of the single-phase auto-coupled transformer in Example 3 are the same as those in Example 2.

[0049] Embodiment 4:

[0050] like Figure 5-7 As shown, when the transformer body is a three-phase transformer and the rated current is greater than 20A, the installation structure of the protection device is:

[0051] A three-phase primary winding, a three-phase secondary winding and an insulating layer are provided on the iron core. The normally closed temperature switch 2 is fixed in the insulating layer. The normally closed temperature switch 2 is provided with three groups and correspondingly fixed to the three-phase secondary winding. The three groups of normally closed temperature switches 2 are connected in series, and the two lead wires after the series connection are connected to the coil signal control point of the AC contactor.

[0052] A preferred technical solution of this embodiment: a heat dissipation channel is provided on the three-phase transformer.

[0053] The specific assembly steps of the three-phase transformer of this embodiment 4 are as follows:

[0054] Step 1: Wind the three-phase primary winding and make the insulation layer, such as Figure 5 As shown;

[0055] Step 2: fix the normally closed temperature switch 2, and then make a heat dissipation channel, such as Figure 6As shown;

[0056] Step 3: Finally, the three-phase secondary winding is completed. After the three-phase transformer is assembled, the two lead wires of the normally closed temperature switch 2 are connected to the coil signal control point of the AC contactor. Figure 7 shown.

[0057] Embodiment 5:

[0058] like Figure 8 As shown, when the transformer body is a three-phase auto-coupling transformer and the rated current is greater than 20A, the installation structure of the protection device is:

[0059] A three-phase primary winding, a three-phase secondary winding and an insulating layer are provided on the iron core. The normally closed temperature switch 2 is fixed in the insulating layer. The normally closed temperature switch 2 is provided with three groups and correspondingly fixed to the three-phase secondary winding. The three groups of normally closed temperature switches 2 are connected in series, and the two lead wires after the series connection are connected to the coil signal control point of the AC contactor.

[0060] The assembly steps of the three-phase auto-coupled transformer in Example 5 are the same as those of the three-phase transformer in Example 4.

[0061] In summary, in the process of transformer manufacturing, two transformer connection structures can be selected according to the size of the working current: the first is to directly reserve the normally closed temperature switch 2 terminal, and the second is to install an AC contactor on the transformer for incoming or outgoing line protection.

[0062] The transformer of the present invention adopts a self-resetting normally closed temperature switch (working current <20A) connected in series in the winding, or (working current >20A) wound between winding layers or between the primary and secondary of the winding, and an external AC contactor is connected in series for input control or output control. The normally open / normally closed conversion of the temperature switch is used as the signal given medium of the AC contactor, thereby realizing real-time monitoring of the transformer's own temperature, and directly controlling the on and off of the AC contactor based on whether the detection signal is abnormal, thereby completing the protection of the transformer's own operation.

[0063] The self-diagnosis protection device of the present invention is based on the reality that the load environment of single-phase and three-phase dry-type transformers is changeable and uncontrolled. It can self-diagnose whether the transformer itself has too high an operating temperature or too large a load, thereby disconnecting the power supply on the input side or the output side for the purpose of self-protection and back-end power protection.

[0064] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A dry-type transformer load self-diagnosis protection device, comprising a transformer body, wherein an iron core and a winding wound on the iron core are arranged in the transformer body, characterized in that: The self-diagnosis protection device also includes: a resettable normally closed temperature switch (2) mounted on the transformer body, on which a temperature sensor is provided, the normally closed temperature switch (2) being connected in series with the winding; an external AC contactor, which is connected in series to the input control or output control end of the winding and is electrically connected to the normally closed temperature switch (2), and uses the normally open / normally closed conversion of the normally closed temperature switch (2) as a signal given medium of the AC contactor, thereby monitoring the temperature of the winding in real time, and a detection circuit directly controls the on / off of the AC contactor when detecting an abnormality in the signal; The installation structure of the protection device includes one of the following four structures: The first structure: when the transformer body is a single-phase transformer and the rated current is less than 20A, the installation structure of the protection device is: a single-phase primary winding, a single-phase secondary winding and an insulation layer are provided on the iron core, the normally closed temperature switch (2) is fixed when the inter-turn insulation layer is wound, the normally closed temperature switch (2) is connected in series with the single-phase primary winding, and its suspended end serves as the input end of the single-phase transformer, wherein the iron core is grounded; The second structure: when the transformer body is a single-phase autotransformer and the rated current is less than 20A, the installation structure of the protection device is: a single-phase primary winding, a single-phase secondary winding and an insulating layer are provided on the iron core, the normally closed temperature switch (2) is fixed to the single-phase secondary winding and fixed through the insulating layer, the normally closed temperature switch (2) is connected in series with the single-phase secondary winding, wherein the iron core is grounded; The third structure: when the transformer body is a three-phase transformer and the rated current is greater than 20A, the installation structure of the protection device is: a three-phase primary winding, a three-phase secondary winding and an insulating layer are provided on the iron core, the normally closed temperature switch (2) is fixed in the insulating layer, the normally closed temperature switch (2) is provided with three groups and correspondingly fixed to the three windings of the three-phase secondary winding, the three groups of the normally closed temperature switches (2) are connected in series, and the two lead wires after the series connection are connected to the coil signal control point of the AC contactor; The fourth structure: when the transformer body is a three-phase auto-coupled transformer and the rated current is greater than 20A, the installation structure of the protection device is: a three-phase primary winding, a three-phase secondary winding and an insulating layer are provided on the iron core, the normally closed temperature switch (2) is fixed in the insulating layer, the normally closed temperature switch (2) is provided with three groups and correspondingly fixed to the three windings of the three-phase secondary winding, the three groups of the normally closed temperature switches (2) are connected in series, and the two lead wires after the series connection are connected to the coil signal control point of the AC contactor; The three-phase transformer is provided with a heat dissipation channel.

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