CN210327005U - Leading protection device of voltage transformer - Google Patents
Leading protection device of voltage transformer Download PDFInfo
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- CN210327005U CN210327005U CN201921525331.1U CN201921525331U CN210327005U CN 210327005 U CN210327005 U CN 210327005U CN 201921525331 U CN201921525331 U CN 201921525331U CN 210327005 U CN210327005 U CN 210327005U
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Abstract
The utility model discloses a leading protection device of voltage transformer, including secondary voltage collection system, secondary voltage comparator, secondary voltage threshold value memory, secondary circuit breaker and the unusual alarm of secondary. The utility model discloses all be provided with protection device in voltage transformer secondary coil return circuit and primary coil return circuit, the automatic circuit that cuts off of dual protection prevents that voltage transformer secondary coil and primary coil from burning out to can protect electrical equipment and personal safety effectively, avoid having a power failure for a long time and change the economic loss that voltage transformer brought.
Description
Technical Field
The utility model belongs to the technical field of voltage transformer, concretely relates to leading protection device of voltage transformer.
Background
In a 10KV power distribution system, a voltage transformer is almost installed on a cable chamber or a handcart, protection is almost installed in an instrument chamber, the transformer and a protection device need to be connected through a cable, the cable is easy to wear when running back and forth in the cabinet, a wire end falls off and is cut and broken, short circuit is caused, when a secondary coil of the voltage transformer is in abnormal conditions such as short circuit and overload, the current is very large, and the secondary coil is easy to burn; the protection of instrument room can not move, and for the fuse of guaranteeing reliability 10KV high-voltage side generally be 0.5A, calculate voltage transformer power and will only fuse the protection beyond 5KW, voltage transformer capacity is very little usually, tens to hundreds of watts, if rely on high-voltage side protection device to protect the transformer, voltage transformer's secondary side burns out very easily.
Therefore, a voltage transformer pre-protection device is required on the secondary side of the voltage transformer.
SUMMERY OF THE UTILITY MODEL
The utility model aims to provide a leading protection device of voltage transformer for solve the voltage transformer among the prior art and all install on cable chamber or handcart almost, the protection is all almost all established in the instrument room, need cable junction between mutual-inductor and the protection device, the cable very easily appears wearing and tearing when shuttling in the cabinet, the end of a thread drops and cuts the broken skin, cause the short circuit, the current is very big when the voltage transformer secondary coil takes place the abnormal conditions such as short circuit, overload, etc., easily burns out the secondary coil; the protection of instrument room can not move, and for the fuse of guaranteeing reliability 10KV high-voltage side generally be 0.5A, calculate voltage transformer power and will exceed 5KW and just can fuse the protection, and voltage transformer capacity is very little usually, tens to hundreds of watts, if rely on high-voltage side protection device to protect the transformer, the problem that voltage transformer's secondary side burns out very easily.
In order to achieve the above object, the utility model adopts the following technical scheme:
a pre-protection device of a voltage transformer comprises a secondary voltage acquisition device, a secondary voltage comparator, a secondary voltage threshold storage, a secondary circuit breaker and a secondary abnormity alarm;
the secondary voltage acquisition device is connected with the secondary voltage comparator and is used for acquiring a real-time voltage signal of the secondary side of the voltage transformer and sending the real-time voltage signal to the secondary voltage comparator;
the secondary voltage threshold storage is connected with the secondary voltage comparator and used for storing a preset secondary voltage threshold signal and sending the secondary voltage threshold signal to the secondary voltage comparator;
the secondary voltage comparator is further connected with the secondary circuit breaker and the secondary abnormity alarm respectively, the secondary voltage comparator compares the real-time voltage signal with the secondary voltage threshold signal, when the real-time voltage signal is larger than the secondary voltage threshold signal, the secondary voltage comparator drives the secondary circuit breaker and the secondary abnormity alarm to act, namely, the secondary circuit breaker breaks the secondary side of the voltage transformer, and the secondary abnormity alarm gives an alarm.
By the scheme, the secondary side voltage signal of the voltage transformer can be acquired in real time, and when the secondary side voltage signal of the voltage transformer is higher than the secondary voltage threshold signal at any moment, the secondary circuit breaker opens the secondary loop coil of the voltage transformer; therefore, the situation that the secondary coil is burnt out due to large current when the secondary coil of the voltage transformer is in abnormal conditions such as short circuit, overload and the like is avoided; and the secondary abnormity alarm gives an alarm to inform maintenance personnel of the voltage transformer to process in time.
Preferably, the protection device further comprises a standby protection element, and the standby protection element is connected in series with the secondary side of the voltage transformer.
Through the scheme, the secondary voltage acquisition device, secondary voltage comparator and secondary circuit breaker all have the possibility of trouble, when any one equipment trouble of secondary voltage acquisition device, secondary voltage comparator and secondary circuit breaker, will lose effect to the protection of voltage transformer secondary side, even design a dedicated fault detection circuit and detect above-mentioned trouble, also can not carry out corresponding protection to the voltage transformer secondary side through secondary circuit breaker this moment, so then need a reserve protection component to carry out second protection to the voltage transformer secondary side, when secondary circuit breaker became invalid, reserve protection component then takes place the short circuit at the voltage transformer secondary coil, open circuit with the voltage transformer secondary side when the abnormal conditions such as overload.
Preferably, the backup protection element is a fuse.
Through the scheme, the fuse can be automatically disconnected when the voltage transformer secondary coil is in abnormal conditions such as short circuit and overload, and if a self-recovery fuse is selected for use, the fuse is in a low-resistance state under normal operation, the heat energy generated by the current flowing through the self-recovery fuse on the circuit is small, the crystal structure in the fuse cannot be changed, when the circuit is in short circuit or overload, the volume of the fuse is rapidly increased due to the heat generated by the large current flowing through the self-recovery fuse, a high-resistance state is formed, the working current is rapidly reduced, and therefore the circuit is limited and protected. When the fault is eliminated, the self-recovery fuse shrinks in weight and recovers to a low-resistance state, so that the circuit is protected without manual replacement.
Preferably, the device also comprises a primary voltage acquisition device, a primary voltage comparator, a primary voltage threshold storage, a primary circuit breaker and a primary abnormity alarm;
the primary voltage acquisition device is connected with the primary voltage comparator and is used for acquiring a real-time voltage signal of a primary side of the voltage transformer and sending the real-time voltage signal of the primary side to the primary voltage comparator;
the primary voltage threshold storage is connected with the primary voltage comparator and used for storing a preset primary voltage threshold signal and sending the primary voltage threshold signal to the primary voltage comparator;
the primary voltage comparator is further connected with the secondary circuit breaker, the primary circuit breaker and the primary abnormity alarm respectively, the primary voltage comparator compares a primary side real-time voltage signal with the primary voltage threshold signal, when the primary side real-time voltage signal is inconsistent with the primary voltage threshold signal, namely the primary side real-time voltage signal is abnormal, the primary voltage comparator drives the secondary circuit breaker, the primary circuit breaker and the primary abnormity alarm to act, namely the secondary circuit breaker breaks a secondary side of a voltage transformer, the primary circuit breaker breaks a primary side of the voltage transformer, and the primary abnormity alarm gives an alarm.
By the scheme, the primary side voltage signal of the voltage transformer can be collected in real time, and when the primary side voltage signal of the voltage transformer is higher than a primary voltage threshold signal at any time, a primary circuit breaker opens a primary loop coil of the voltage transformer; therefore, the situation that the primary coil is burnt out due to large current when the primary coil of the voltage transformer is in an abnormal condition is avoided; and the primary abnormity alarm gives an alarm to inform voltage transformer maintenance personnel to process in time. It should be noted that, after the primary side circuit is broken due to abnormal conditions, and the maintenance personnel removes the fault, the primary side circuit is turned on again, and if the voltage is too large, the secondary side voltage is directly overloaded, so that when the primary side circuit is broken due to abnormal conditions, the secondary side circuit is also turned off under the action of the secondary circuit breaker, and after the primary side circuit is removed, the voltage of the primary side circuit is detected and confirmed, and then the secondary side circuit is turned on, which is beneficial to the protection of the secondary side circuit.
Preferably, the secondary voltage comparator is further connected to the primary circuit breaker, and when the real-time voltage signal is greater than the secondary voltage threshold signal, the secondary voltage comparator drives the primary circuit breaker to operate.
According to the scheme, after the secondary side loop is subjected to protection action disconnection due to abnormal conditions such as short circuit and overload, the primary side loop is still in a closed circuit state, and the primary side loop is still in abnormal risks such as short circuit and overload during secondary side fault removal, so that the secondary side loop is subjected to protection action disconnection due to abnormal conditions such as short circuit and overload, and the primary side loop is disconnected through the primary breaker, so that the primary side loop is protected.
Preferably, the transformer further comprises a primary side backup protection element, and the primary side backup protection element is connected in series with the primary side of the voltage transformer.
Through the scheme, the primary voltage acquisition device, the primary voltage comparator and the primary circuit breaker have the possibility of faults, when any one of the primary voltage acquisition device, the primary voltage comparator and the primary circuit breaker fails, the protection on the primary side of the voltage transformer is disabled, even if a special fault detection circuit is designed to detect the faults, the primary side of the voltage transformer cannot be correspondingly protected through the primary circuit breaker, so that a spare protection element is needed to perform secondary protection on the primary side of the voltage transformer, and when the primary circuit breaker fails, the spare protection element opens the primary side of the voltage transformer when abnormal conditions such as short circuit, overload and the like occur to a primary coil of the voltage transformer.
Preferably, the primary side backup protection element is a fuse.
Through the scheme, the fuse can be automatically disconnected when the voltage transformer secondary coil is in abnormal conditions such as short circuit and overload, and if a self-recovery fuse is selected for use, the fuse is in a low-resistance state under normal operation, the heat energy generated by the current flowing through the self-recovery fuse on the circuit is small, the crystal structure in the fuse cannot be changed, when the circuit is in short circuit or overload, the volume of the fuse is rapidly increased due to the heat generated by the large current flowing through the self-recovery fuse, a high-resistance state is formed, the working current is rapidly reduced, and therefore the circuit is limited and protected. When the fault is eliminated, the self-recovery fuse shrinks in weight and recovers to a low-resistance state, so that the circuit is protected without manual replacement.
The utility model has the beneficial technical effects that: the utility model discloses all be provided with protection device in voltage transformer secondary coil return circuit and primary coil return circuit, the automatic circuit that cuts off of dual protection prevents that voltage transformer secondary coil and primary coil from burning out to can protect electrical equipment and personal safety effectively, avoid having a power failure for a long time and change the economic loss that voltage transformer brought.
Drawings
Fig. 1 shows a schematic structural diagram of embodiment 1 of the present invention.
Fig. 2 is a schematic circuit diagram according to embodiment 2 of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to fig. 1-2 of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
Example 1:
as shown in fig. 1, a front protection device of a voltage transformer comprises a secondary voltage acquisition device, a secondary voltage comparator, a secondary voltage threshold memory, a secondary circuit breaker and a secondary abnormal alarm;
the secondary voltage acquisition device is connected with the secondary voltage comparator and is used for acquiring a real-time voltage signal of the secondary side of the voltage transformer and sending the real-time voltage signal to the secondary voltage comparator;
the secondary voltage threshold storage is connected with the secondary voltage comparator and used for storing a preset secondary voltage threshold signal and sending the secondary voltage threshold signal to the secondary voltage comparator;
the secondary voltage comparator is further connected with the secondary circuit breaker and the secondary abnormity alarm respectively, the secondary voltage comparator compares the real-time voltage signal with the secondary voltage threshold signal, when the real-time voltage signal is larger than the secondary voltage threshold signal, the secondary voltage comparator drives the secondary circuit breaker and the secondary abnormity alarm to act, namely, the secondary circuit breaker breaks the secondary side of the voltage transformer, and the secondary abnormity alarm gives an alarm.
The working principle of the embodiment is briefly described as follows: the secondary side voltage signal of the voltage transformer can be collected in real time, and when the secondary side voltage signal of the voltage transformer is higher than a secondary voltage threshold signal at any time, a secondary circuit breaker opens a secondary loop coil of the voltage transformer; therefore, the situation that the secondary coil is burnt out due to large current when the secondary coil of the voltage transformer is in abnormal conditions such as short circuit, overload and the like is avoided; and the secondary abnormity alarm gives an alarm to inform maintenance personnel of the voltage transformer to process in time.
In this embodiment, it is preferable that the protection circuit further includes a backup protection element, and the backup protection element is connected in series to the secondary side of the voltage transformer.
Through the scheme, the secondary voltage acquisition device, secondary voltage comparator and secondary circuit breaker all have the possibility of trouble, when any one equipment trouble of secondary voltage acquisition device, secondary voltage comparator and secondary circuit breaker, will lose effect to the protection of voltage transformer secondary side, even design a dedicated fault detection circuit and detect above-mentioned trouble, also can not carry out corresponding protection to the voltage transformer secondary side through secondary circuit breaker this moment, so then need a reserve protection component to carry out second protection to the voltage transformer secondary side, when secondary circuit breaker became invalid, reserve protection component then takes place the short circuit at the voltage transformer secondary coil, open circuit with the voltage transformer secondary side when the abnormal conditions such as overload.
In this embodiment, the spare protection element is preferably a fuse.
Through the scheme, the fuse can be automatically disconnected when the voltage transformer secondary coil is in abnormal conditions such as short circuit and overload, and if a self-recovery fuse is selected for use, the fuse is in a low-resistance state under normal operation, the heat energy generated by the current flowing through the self-recovery fuse on the circuit is small, the crystal structure in the fuse cannot be changed, when the circuit is in short circuit or overload, the volume of the fuse is rapidly increased due to the heat generated by the large current flowing through the self-recovery fuse, a high-resistance state is formed, the working current is rapidly reduced, and therefore the circuit is limited and protected. When the fault is eliminated, the self-recovery fuse shrinks in weight and recovers to a low-resistance state, so that the circuit is protected without manual replacement.
Example 2:
as shown in fig. 2, on the basis of embodiment 1, it is preferable that the emergency protection circuit further includes a primary voltage acquisition device, a primary voltage comparator, a primary voltage threshold memory, a primary circuit breaker, and a primary abnormality alarm;
the primary voltage acquisition device is connected with the primary voltage comparator and is used for acquiring a real-time voltage signal of a primary side of the voltage transformer and sending the real-time voltage signal of the primary side to the primary voltage comparator;
the primary voltage threshold storage is connected with the primary voltage comparator and used for storing a preset primary voltage threshold signal and sending the primary voltage threshold signal to the primary voltage comparator;
the primary voltage comparator is further connected with the secondary circuit breaker, the primary circuit breaker and the primary abnormity alarm respectively, the primary voltage comparator compares a primary side real-time voltage signal with the primary voltage threshold signal, when the primary side real-time voltage signal is inconsistent with the primary voltage threshold signal, namely the primary side real-time voltage signal is abnormal, the primary voltage comparator drives the secondary circuit breaker, the primary circuit breaker and the primary abnormity alarm to act, namely the secondary circuit breaker breaks a secondary side of a voltage transformer, the primary circuit breaker breaks a primary side of the voltage transformer, and the primary abnormity alarm gives an alarm.
The working principle of the embodiment is briefly described as follows: the primary side voltage signal of the voltage transformer can be collected in real time, and when the primary side real-time voltage signal of the voltage transformer is not consistent with the primary voltage threshold signal at any time, the primary circuit breaker opens a primary loop coil of the voltage transformer; thereby avoiding the situation that the primary coil is burnt out due to the abnormal situation of the primary coil of the voltage transformer; and the primary abnormity alarm gives an alarm to inform voltage transformer maintenance personnel to process in time. It should be noted that, after the primary side circuit is broken due to abnormal conditions, and the maintenance personnel removes the fault, the primary side circuit is turned on again, and if the voltage is too large, the secondary side voltage is directly overloaded, so that when the primary side circuit is broken due to abnormal conditions, the secondary side circuit is also turned off under the action of the secondary circuit breaker, and after the primary side circuit is removed, the voltage of the primary side circuit is detected and confirmed, and then the secondary side circuit is turned on, which is beneficial to the protection of the secondary side circuit.
In this embodiment, preferably, the secondary voltage comparator is further connected to the primary circuit breaker, and when the real-time voltage signal is greater than the secondary voltage threshold signal, the secondary voltage comparator drives the primary circuit breaker to operate.
According to the scheme, after the secondary side loop is subjected to protection action disconnection due to abnormal conditions such as short circuit and overload, the primary side loop is still in a closed circuit state, and the primary side loop is still in abnormal risks such as short circuit and overload during secondary side fault removal, so that the secondary side loop is subjected to protection action disconnection due to abnormal conditions such as short circuit and overload, and the primary side loop is disconnected through the primary breaker, so that the primary side loop is protected.
In this embodiment, it is preferable that the voltage transformer further includes a primary side backup protection element connected in series to a primary side of the voltage transformer.
Through the scheme, the primary voltage acquisition device, the primary voltage comparator and the primary circuit breaker have the possibility of faults, when any one of the primary voltage acquisition device, the primary voltage comparator and the primary circuit breaker fails, the protection on the primary side of the voltage transformer is disabled, even if a special fault detection circuit is designed to detect the faults, the primary side of the voltage transformer cannot be correspondingly protected through the primary circuit breaker, so that a spare protection element is needed to perform secondary protection on the primary side of the voltage transformer, and when the primary circuit breaker fails, the spare protection element opens the primary side of the voltage transformer when abnormal conditions such as short circuit, overload and the like occur to a primary coil of the voltage transformer.
In this embodiment, the primary side backup protection element is preferably a fuse.
Through the scheme, the fuse can be automatically disconnected when the voltage transformer secondary coil is in abnormal conditions such as short circuit and overload, and if a self-recovery fuse is selected for use, the fuse is in a low-resistance state under normal operation, the heat energy generated by the current flowing through the self-recovery fuse on the circuit is small, the crystal structure in the fuse cannot be changed, when the circuit is in short circuit or overload, the volume of the fuse is rapidly increased due to the heat generated by the large current flowing through the self-recovery fuse, a high-resistance state is formed, the working current is rapidly reduced, and therefore the circuit is limited and protected. When the fault is eliminated, the self-recovery fuse shrinks in weight and recovers to a low-resistance state, so that the circuit is protected without manual replacement.
It should be noted that the secondary voltage comparator and the primary voltage comparator of the present invention are analog electronic circuits or digital logic circuits in the prior art, and the innovation point of the present invention is not on a single circuit, and does not relate to the improvement of computer software and programs.
In the description of the present invention, it should be understood that the terms "counterclockwise", "clockwise", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description of the present invention, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.
Claims (7)
1. A voltage transformer front protection device is characterized by comprising a secondary voltage acquisition device, a secondary voltage comparator, a secondary voltage threshold storage, a secondary circuit breaker and a secondary abnormity alarm;
the secondary voltage acquisition device is connected with the secondary voltage comparator and is used for acquiring a real-time voltage signal of the secondary side of the voltage transformer and sending the real-time voltage signal to the secondary voltage comparator;
the secondary voltage threshold storage is connected with the secondary voltage comparator and used for storing a preset secondary voltage threshold signal and sending the secondary voltage threshold signal to the secondary voltage comparator;
the secondary voltage comparator is further connected with the secondary circuit breaker and the secondary abnormity alarm respectively, the secondary voltage comparator compares the real-time voltage signal with the secondary voltage threshold signal, when the real-time voltage signal is larger than the secondary voltage threshold signal, the secondary voltage comparator drives the secondary circuit breaker and the secondary abnormity alarm to act, namely, the secondary circuit breaker breaks the secondary side of the voltage transformer, and the secondary abnormity alarm gives an alarm.
2. The pre-protection device for the voltage transformer as claimed in claim 1, further comprising a backup protection element, wherein the backup protection element is connected in series with the secondary side of the voltage transformer.
3. The pre-protection device for the voltage transformer according to claim 2, wherein the backup protection element is a fuse.
4. The front protection device of the voltage transformer according to any one of claims 1 to 3, further comprising a primary voltage acquisition device, a primary voltage comparator, a primary voltage threshold memory, a primary circuit breaker and a primary abnormality alarm;
the primary voltage acquisition device is connected with the primary voltage comparator and is used for acquiring a real-time voltage signal of a primary side of the voltage transformer and sending the real-time voltage signal of the primary side to the primary voltage comparator;
the primary voltage threshold storage is connected with the primary voltage comparator and used for storing a preset primary voltage threshold signal and sending the primary voltage threshold signal to the primary voltage comparator;
the primary voltage comparator is further connected with the secondary circuit breaker, the primary circuit breaker and the primary abnormity alarm respectively, the primary voltage comparator compares a primary side real-time voltage signal with the primary voltage threshold signal, and when the primary side real-time voltage signal is not consistent with the primary voltage threshold signal, the primary voltage comparator drives the secondary circuit breaker, the primary circuit breaker and the primary abnormity alarm to act, namely the secondary circuit breaker breaks a secondary side of a voltage transformer, the primary circuit breaker breaks a primary side of the voltage transformer, and the primary abnormity alarm gives an alarm.
5. The pre-protection device of claim 4, wherein the secondary voltage comparator is further connected to the primary circuit breaker, and when the real-time voltage signal is greater than the secondary voltage threshold signal, the secondary voltage comparator drives the primary circuit breaker to operate.
6. The pre-protection device of claim 4, further comprising a primary side backup protection element, wherein the primary side backup protection element is connected in series with the primary side of the voltage transformer.
7. The pre-protection device of claim 6, wherein the primary side backup protection element is a fuse.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921525331.1U CN210327005U (en) | 2019-09-12 | 2019-09-12 | Leading protection device of voltage transformer |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921525331.1U CN210327005U (en) | 2019-09-12 | 2019-09-12 | Leading protection device of voltage transformer |
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| CN210327005U true CN210327005U (en) | 2020-04-14 |
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| CN201921525331.1U Active CN210327005U (en) | 2019-09-12 | 2019-09-12 | Leading protection device of voltage transformer |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112557741A (en) * | 2020-12-25 | 2021-03-26 | 广东电网有限责任公司 | Secondary voltage detection device and detection method for voltage transformer |
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2019
- 2019-09-12 CN CN201921525331.1U patent/CN210327005U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112557741A (en) * | 2020-12-25 | 2021-03-26 | 广东电网有限责任公司 | Secondary voltage detection device and detection method for voltage transformer |
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