CN213716707U

CN213716707U - Mutual inductor and circuit breaker

Info

Publication number: CN213716707U
Application number: CN202023292000.3U
Authority: CN
Inventors: 王欢; 邓国平; 叶文杰
Original assignee: Changshu Switchgear Manufacturing Co Ltd
Current assignee: Changshu Switchgear Manufacturing Co Ltd
Priority date: 2020-12-30
Filing date: 2020-12-30
Publication date: 2021-07-16
Anticipated expiration: 2030-12-30

Abstract

The utility model discloses a mutual inductor. The transformer comprises a shell, and an iron core and a winding coil which are arranged in the shell; thermosensitive devices are integrated in the mutual inductor. The utility model also discloses a circuit breaker. The utility model provides a mutual-inductor integration has thermosensitive device, can carry out real-time supervision to mutual-inductor operating temperature to effectively improve the fail safe nature of circuit breaker.

Description

Mutual inductor and circuit breaker

Technical Field

The utility model relates to a mutual inductor.

Background

In a low-voltage power system, a circuit breaker is widely used, and functions of a controller serving as a core component of the circuit breaker are improved, and besides conventional electric parameter measurement and protection functions, the controller is additionally provided with a plurality of additional functions, such as state monitoring, system maintenance and the like. Because the circuit breaker belongs to the long-term circular telegram work product, along with the time, each part of circuit breaker has the temperature rise of different degrees, and people need monitor these parts that heat up to cause unnecessary harm after it surpasss certain degree. The circuit breakers commonly used in the market at present mostly have the overtemperature alarm function of a controller, and a small number of circuit breakers have the monitoring of the busbar temperature and the contact temperature, but have less temperature monitoring on a mutual inductor.

The mutual inductor is also called instrument transformer, and is a general name of current mutual inductor and voltage mutual inductor. It can change high voltage into low voltage and large current into small current for measuring or protecting system. Its function is mainly to convert high voltage or large current into standard low voltage (100V) or standard small current (5A or 1A, both referring to rated value) in proportion so as to realize standardization and miniaturization of measuring instrument, protection equipment and automatic control equipment. Meanwhile, the mutual inductor can be used for isolating a high-voltage system so as to ensure the safety of people and equipment. The transformer generally includes a housing, and a core and a winding coil mounted in the housing, and a bobbin, a terminal, and the like. The current transformer which is used most frequently in the circuit breaker is provided with a detection coil for current detection and an energy coil for drawing electric energy from a main line, so that the current transformer with the detection coil and the energy coil generates a large amount of heat in the working process, and the temperature change condition of the current transformer is more necessary to be monitored in real time.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that overcome prior art not enough, provide one kind and can carry out real-time supervision's mutual-inductor to its operating temperature.

The utility model discloses specifically adopt following technical scheme to solve above-mentioned technical problem:

a mutual inductor comprises a shell, and a core, a winding coil and an assembly board which are arranged in the shell; the winding coil comprises an energy coil, the assembly plate comprises a rectifying circuit, the input end of the rectifying circuit is connected with the energy coil wound on the iron core, a thermosensitive device is integrated in the transformer, and the thermosensitive device is installed on the assembly plate and used for inducing the temperature change of the current transformer.

Furthermore, the assembly plate is located inside the current transformer and clamped in a groove in a transformer shell, the assembly plate is close to an energy coil wound on the iron core, the thermosensitive device is welded on the assembly plate, and the thermosensitive device is close to the energy coil.

Preferably, the thermosensitive device is a thermistor.

Based on the same inventive concept, the following technical scheme can be obtained:

a circuit breaker comprises the mutual inductor in any technical scheme.

Further, the circuit breaker also comprises a display module capable of displaying the temperature of the mutual inductor collected by the thermosensitive device.

Furthermore, the circuit breaker also comprises an alarm module which can give an alarm when the temperature of the mutual inductor collected by the thermosensitive device exceeds a preset range.

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model provides a mutual-inductor integration has thermosensitive device, can carry out real-time supervision to mutual-inductor operating temperature to effectively improve the fail safe nature of circuit breaker.

Drawings

Fig. 1 is a schematic structural diagram of a specific embodiment of the transformer of the present invention;

fig. 2 is an exploded view of an embodiment of the transformer of the present invention;

fig. 3 is a block diagram of a circuit structure of a specific embodiment of the circuit breaker of the present invention;

fig. 4 is a specific implementation circuit of the sampling circuit.

The reference numerals in the figures have the following meanings:

100. the current transformer comprises a current transformer body 1, a shell 2, a measuring coil 3, an iron core 4, an energy coil 5, a component board 6, a thermistor 7, a connector 8 and a clamping groove.

Detailed Description

Not enough to prior art, the utility model discloses a solution thinking is the thermosensitive device of integration in the mutual-inductor to the realization is to the real-time supervision of mutual-inductor temperature.

Particularly, the utility model discloses a mutual inductor, including the shell and install iron core, winding coil and the subassembly board in the shell; the winding coil comprises an energy coil, the assembly plate comprises a rectifying circuit, the input end of the rectifying circuit is connected with the energy coil wound on the iron core, a thermosensitive device is integrated in the transformer, and the thermosensitive device is installed on the assembly plate and used for inducing the temperature change of the current transformer.

Preferably, the thermosensitive device is a thermistor.

a circuit breaker comprises a mutual inductor, wherein the mutual inductor is the mutual inductor in any technical scheme.

For the public understanding, the technical scheme of the invention is explained in detail below with the accompanying drawings:

the current transformer 100 of the present embodiment is a current transformer as shown in fig. 1 and fig. 2, and includes a housing 1, and a core 3, an assembly board 5 and a winding coil installed in the housing 1, where the winding coil in the present embodiment includes a measuring coil 2 and an energy coil 4; the assembly board 5 is provided with a rectifying circuit and a thermistor 6, and the input end of the rectifying circuit is connected with the energy coil 4 and used for converting alternating current output by the energy coil 4 into direct current; the thermistor 6 is welded on the component board 5 and used for sensing the temperature condition of the current transformer 100; the rectifying circuit and the thermistor 6 are both output through a connector 7. As shown in fig. 1 and 2, the assembly board 5 is clamped in a clamping groove 8 in the housing 1 and is sealed by glue injection; since the energy coil is the main heating component of the current transformer, the thermistor 6 is mounted on the assembly board 5 close to and as close as possible to the energy coil 4, so that the temperature rise of the transformer can be more accurately represented by the signal detected by the thermistor.

Fig. 3 shows the basic circuit structure of the circuit breaker using the above-mentioned mutual inductor, as shown in fig. 3, the thermistor is connected with the circuit breaker controller through the connector, the circuit breaker controller includes the sampling circuit and the microprocessor circuit, the sampling circuit adopts the voltage division mode to collect the voltage signal transmitted from the thermosensitive device, and transmits the signal to the microprocessor of the controller; the microprocessor displays the processed temperature signal through the display unit, and a user can inquire in a corresponding menu; if the controller is not provided with a display unit, the signal can be transmitted to an upper computer through a communication unit and is inquired by the upper computer; when the temperature of the mutual inductor reaches a certain value, the controller outputs an alarm signal, and an alarm output circuit can use an alarm module inherent to the circuit breaker or is additionally arranged on the controller. When the circuit breaker works, the energy coil of the current transformer generates heat, the thermistor close to the energy coil induces the temperature change of the transformer, the sampling circuit collects voltage signals transmitted by the thermistor and transmits the signals to the microprocessor, the microprocessor converts the signals into user inquireable information, a user can check the temperature of the transformer in real time on a human-computer interface of the controller, and the user can also remotely inquire the temperature of the transformer on an upper computer. If the temperature of the mutual inductor exceeds the set threshold value, the controller gives an alarm, and an alarm output circuit can use an alarm module of the circuit breaker or an alarm output module is additionally arranged on the controller.

Fig. 4 shows a specific circuit configuration of the voltage division type sampling circuit, and as shown in fig. 4, a temperature change signal detected by a thermistor in the A, B, C mutual sensor enters the sampling circuit through connectors X8, X9 and X10. Taking phase A as an example: the resistor R37, the power supply VDD and the ground form a resistor voltage dividing circuit for collecting voltage signals on the thermistor, the inductor L6 and the capacitor C25 form an LC filter circuit for filtering interference signals in the circuit, and the processed signals are sent to the microprocessor.

Claims

1. A mutual inductor comprises a shell, and a core, a winding coil and an assembly board which are arranged in the shell; the winding coil comprises an energy coil, the assembly plate comprises a rectifying circuit, and the input end of the rectifying circuit is connected with the energy coil wound on the iron core.

2. The instrument transformer of claim 1, wherein the assembly plate is positioned within the current transformer and is captured within a recess in the transformer housing, the assembly plate being adjacent to the energy coil wound on the core, the heat sensitive device being soldered to the assembly plate, the heat sensitive device being proximate to the energy coil.

3. The instrument of claim 1 wherein said heat sensitive device is a thermistor.

4. A circuit breaker comprising a transformer according to any one of claims 1 to 3.

5. The circuit breaker of claim 4, further comprising a display module capable of displaying the transformer temperature collected by the heat sensitive device.

6. The circuit breaker of claim 4, further comprising an alarm module capable of alarming when the temperature of the transformer collected by the heat sensitive device is out of a preset range.