CN104991155B - A kind of security detection equipment for transformer - Google Patents

Abstract

The present invention provides a kind of security detection equipment for transformer, and the security detection equipment includes：Main control unit (1), detection of electrical leakage module (2), electric leakage acquisition module (3), power failure protection module (4), alarm modules (5), display module (6) and power module (7)；The main control unit (1) is connected with the detection of electrical leakage module (2), the electric leakage acquisition module (3), simulation electric leakage module (4), the alarm modules (5) and the display module (6) respectively, and the detection of electrical leakage module (2) is connected with electric leakage acquisition module (3)；The power module (7) is connected by wire with other modules.

Description

A safety detection device for transformer

technical field

The invention relates to the field of strong current protection, in particular to a leakage detection device for detecting transformer leakage.

Background technique

A transformer is an electrical device used to convert high voltage to low voltage. Because the high voltage in the transformer is extremely harmful to the human body, once the transformer leaks, it is easy to cause an electric shock accident. Electric shock refers to the passage of electric current in the human body. When electric current passes through the human body and causes injury, there are two situations: one is electric shock, and the other is electric injury. Electric shock is the passage of electric current through the inside of the human body, causing damage to human tissue. The danger of this kind of injury is very high, which can damage the human heart, breathing function and brain nervous system, and even cause death. Electric injury is the damage caused by electric current to the outside of the human body, including burns, electric branding, and metallization of the skin. Electric injury is less harmful than electric shock.

The degree of harm of electric current to the human body is related to various factors such as the intensity of the current passing through the human body, the duration of the current, the frequency of the current, the way the current passes through the human body, and the physical condition of the person who is electrocuted.

At present, there are already some protective devices for low-voltage distribution transformers (referred to as transformers). For example, there are various high-voltage circuit breakers, lightning arresters, etc. on the high-voltage side, and various fuses, AC contactors, phase-detection and amplitude-detection relays, etc. on the low-voltage side. Despite such protective measures, due to the variety of transformer capacity levels and complex circuits, it is difficult to ensure that the various protective measures are foolproof, especially the leakage fault of the transformer, which may occur in any part, and the general leakage protection is in the main circuit, and the effectiveness of the leakage protection circuit itself cannot be monitored in real time, resulting in the failure to detect transformer leakage faults in time, leading to accidents, especially for transformer maintenance personnel and personnel around the transformer. It is easy to cause an electric shock accident.

Contents of the invention

In view of the above problems, the present invention hopes to overcome the deficiencies in the prior art, and provide a safety detection device for transformers that is convenient for on-site use.

In order to solve the above-mentioned technical problems, the technical solution adopted in the present invention is: a safety detection device for transformers, which is used to detect whether the transformers are leaking, and is characterized in that: the safety detection devices for transformers include: a main control unit , a leakage detection module, a leakage acquisition module, a power failure protection module, an alarm module, a display module and a power supply module; the main control unit is respectively connected with the leakage detection module, the leakage acquisition module, the analog leakage module, the The alarm module is connected to the display module, the leakage detection module is connected to the leakage acquisition module; the power supply module is directly or indirectly connected to the main control unit, the leakage detection module, the leakage acquisition module, the analog leakage module, The alarm module is connected with the display module so as to supply power to each module, and the safety detection device also includes a jumper circuit.

The jumper circuit is connected to the high-voltage side of the transformer, one end of the jumper circuit is connected to the input end of the transformer, and the other end is connected to the input end of the backup transformer, when the main control unit detects that a leakage accident occurs , control the power-off protection module to disconnect the power-off protection module, and drive the bridging circuit to close, leading the high-voltage input of the transformer to the standby transformer.

In a preferred implementation manner, the leakage current acquisition module includes a voltage transformer and a current transformer, the voltage transformer and the current transformer are respectively installed in the output circuit of the transformer, and the voltage transformer and the The outputs of the current transformers are respectively connected to the leakage detection module, and the leakage detection module measures the output voltage and output current of the voltage transformer and the current transformer.

In a preferred implementation manner, the leakage detection device further includes a temperature detection module, and the temperature detection module is connected to the main control unit.

In a preferred implementation manner, the leakage detection device is installed in an insulating casing.

In a preferred implementation manner, the main control unit is an AT89C1051 chip.

In a preferred implementation manner, the alarm module is an alarm speaker.

In a preferred implementation manner, the display module is a liquid crystal display.

In a preferred implementation manner, the voltage transformer is a GY type voltage transformer produced by Wuhan Hengxin Guoyi Technology Co., Ltd.

In another preferred implementation manner, the jumper circuit includes a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, a potential difference resistor R1, a single-pole bidirectional switch K1, and a circuit breaker DL1.

In this implementation, the positive pole of the high-voltage line is connected to the potential difference resistor R1, and is connected to the first end of the first capacitor C1 and the first end of the first inductor L1, and the other end of the potential difference resistor R1 is connected to the first capacitor The second terminal of C1, the first terminal of the second inductor L2, the second terminal of the first inductor L1 is connected to the first terminal of the second capacitor C2, the second terminal of the second capacitor C2 is connected to the first terminal of the second inductor L2 Two ends. One end of the single-pole bidirectional switch K1 is connected to the first end of the second capacitor C2, and the other two terminals A and B are connected to two primary coils, primary coil 1 and primary coil 2, respectively. The other ends of the primary coil 1 and the primary coil 2 are respectively connected to the negative pole of the high voltage line. It should be noted that, in this preferred implementation, due to the use of an inductor, it is only applicable to a relatively low input voltage, and is not applicable to an input voltage higher than 3000V.

In addition, the capacitors used in this implementation are high voltage withstand capacitors. The primary coil 1 is the primary coil of the transformer in normal use, and the primary coil 2 is the primary coil of the standby transformer. The two inductors L1 and L2 are wound in the opposite way to each other, and the two are placed side by side, so that for the outside, the two generated by the two generally cancel each other, and for the inside, the two generate their own magnetic field. Normally, switch K1 is connected to terminal A, and the transformer on the lower side works. And once the leakage occurs in the normally used transformer, the switch K1 jumps to the terminal B to start the backup transformer. Although the switching time of the switch is very short, it will still have a certain impact on the electrical equipment connected to the output terminal of the transformer. If the circuit of the present invention is not used, the voltage curve in the output line will appear disconnected during the switching process Phase, that is, the voltage curve in the output line will appear out of gear. After adopting the circuit in this implementation mode, even if there is a leakage, during the jump process, L1 and L2 will store the electric energy at the input end, and after the jump is completed, L1 and L2 will release the electric energy and output the electric energy in the circuit. The supply phase is completed (although there is some compression, the curve is complete). This is of great benefit to some special devices that have requirements on the waveform integrity of the power supply circuit.

In another preferred implementation manner, the safety detection device includes an analog leakage module, the analog leakage module is connected to the high-voltage input terminal of the transformer, the analog leakage module includes an analog switch and a voltage divider, the analog switch is connected to the The voltage dividing device is connected in series, and the voltage dividing device is connected with the casing of the transformer through a protection circuit. The simulated leakage module can output part of the high voltage to the transformer shell to simulate leakage.

Compared with the prior art, the present invention has the beneficial effects that: the present invention collects the leakage conditions of each equipment of the transformer through the leakage collection module, and sends the leakage conditions to the leakage detection module, which is connected to the alarm and display module through the main control unit. Leakage alarm and display can be issued, which can measure the leakage situation on the transformer site, which is convenient to use. At the same time, it can detect the leakage information of various parts, and the detection is accurate. It is also equipped with an analog leakage module, which can detect whether the transformer leakage detection circuit is effective; the whole device structure Simple and easy to use.

Description of drawings

Below in conjunction with accompanying drawing, the present invention is described in further detail:

Fig. 1 is a schematic diagram of the circuit structure of the present invention; in the figure: 1 is the main control unit, 2 is the leakage detection module, 3 is the leakage acquisition module, 4 is the analog leakage module, 5 is the alarm module, 6 is the display module, and 7 is the power supply Module 8 is a temperature detection module.

Fig. 2 shows a schematic circuit diagram of the part used to protect the circuit in the monitoring device of the present invention.

FIG. 3 is a schematic diagram of the circuit structure of the leakage collection module.

Detailed ways

As shown in Figure 1, the safety detection equipment for the transformer of the present invention includes: a main control unit 1, a leakage detection module 2, a leakage acquisition module 3, a power failure protection module 4, an alarm module 5, a display module 6 and a power supply module 7 The main control unit 1 is connected to the leakage detection module 2, the leakage acquisition module 3, the power failure protection module 4, the alarm module 5 and the display module 6 respectively, and the leakage detection module 2 is connected to the leakage acquisition module 3; the power supply Module 7 supplies power to the entire device.

The main control unit 1 can adopt a single-chip microcomputer circuit, and the main control chip can adopt a chip whose model is AT89C1051. Or the main control unit 1 can use two comparators. The main control unit 1 controls the work of the whole device. The leakage acquisition module 3 includes a voltage transformer and a current transformer. The voltage transformer and the current transformer are respectively installed in the output circuit of the transformer and connected in series with the output circuit of the transformer. The leakage acquisition module 3 may also include a casing current detection circuit and a ground current detection circuit. The above-mentioned circuits can be realized by a wire with a large resistance, respectively connected to the transformer casing and the ground wire, and react by detecting the current situation of the above-mentioned devices. Transformer leakage condition. The output signal of the leakage collection module 3 is sent to the leakage detection module 2, and the leakage detection module 2 can determine whether there is a leakage based on the output of the leakage collection module.

For example, if the voltage induced by the voltage transformer does not change, but the current induced by the current transformer changes suddenly, it is determined that leakage occurs. Then the leakage detection module 2 can output high level, otherwise output low level. The output of the leakage detection module 2 is sent to the main control unit 1, and the main control unit 1 outputs a corresponding signal to the alarm module based on the output, and outputs a high level to the alarm module, and then the alarm module sends an alarm, otherwise, the alarm module remains silent. In addition, the main control unit also outputs high level or low level to the display module. The display module can be a liquid crystal display, in which a preset alarm picture is stored in advance, and once the main control unit sends out an alarm signal, the module will display the preset alarm picture within a limited time.

The invention can be conveniently connected at the transformer site, and rapidly detects the leakage conditions of various parts of the transformer, accurately alarms, and facilitates the operation of site personnel.

The leakage detection device also includes a temperature detection module 8, the temperature detection module 8 is connected to the above-mentioned main control unit 1, many leakages on the transformer will cause local heating of the transformer, and the temperature detection module 8 can detect internal, The temperature at the top can be used to judge whether the transformer is faulty.

The leakage detection device is installed in an insulating casing, and the above-mentioned main control unit 1, leakage detection module 2, power module 7 and temperature detection module 8 can all be installed inside the insulation casing; the above-mentioned leakage collection module 3 and the analog leakage module 4 The detection circuit is installed in the insulating casing, and the detection element can be connected with the detection circuit through the insulated wire connection; the above-mentioned alarm module 5 and display module 6 are installed on the insulating casing, and the whole device has a simple structure and can be easily carried.

FIG. 2 shows a schematic circuit diagram of an implementation of a jumper circuit.

As shown in the figure, the jumper circuit includes a first inductor L1, a second inductor L2, a first capacitor C1, a second capacitor C2, a potential difference resistor R1, a single-pole bidirectional switch K1, and a circuit breaker DL1.

In this implementation, the positive pole of the high-voltage line is connected to the potential difference resistor R1, and is connected to the first end of the first capacitor C1 and the first end of the first inductor L1, and the other end of the potential difference resistor R1 is connected to the first capacitor The second terminal of C1, the first terminal of the second inductor L2, the second terminal of the first inductor L1 is connected to the first terminal of the second capacitor C2, the second terminal of the second capacitor C2 is connected to the first terminal of the second inductor L2 Two ends. One end of the single-pole bidirectional switch K1 is connected to the first end of the second capacitor C2, and the other two terminals A and B are connected to two primary coils, primary coil 1 and primary coil 2, respectively. The other ends of the primary coil 1 and the primary coil 2 are respectively connected to the negative pole of the high voltage line. It should be noted that, in this preferred implementation, due to the use of an inductor, it is only applicable to a relatively low input voltage, and is not applicable to an input voltage higher than 2000V.

In addition, the capacitors used in this implementation are high voltage withstand capacitors. The primary coil 1 is the primary coil of the transformer in normal use, and the primary coil 2 is the primary coil of the standby transformer. The two inductors L1 and L2 are wound in the opposite way to each other, and the two are placed side by side, so that for the outside, the two generated by the two generally cancel each other, and for the inside, the two generate their own magnetic field. Normally, switch K1 is connected to terminal A, and the transformer on the lower side works. And once the leakage occurs in the normally used transformer, the switch K1 jumps to the terminal B to start the backup transformer. Although the switching time of the switch is very short, it will still have a certain impact on the electrical equipment connected to the output terminal of the transformer. If the circuit of the present invention is not used, the voltage curve in the output line will appear disconnected during the switching process Phase, that is, the voltage curve in the output line will appear out of gear. After adopting the circuit in this implementation mode, even if there is a leakage, during the jump process, L1 and L2 will store the electric energy at the input end, and after the jump is completed, L1 and L2 will release the electric energy and output the electric energy in the circuit. The supply phase is completed (although there is some compression, the curve is complete). This is of great benefit to some special devices that have requirements on the waveform integrity of the power supply circuit.

As shown in Figure 3, the leakage acquisition module 5 includes a current transformer, a resistor R10, a second resistor R20, a resistor R30, a resistor R40, a fifth resistor R50, a diode D10, a diode D20, a capacitor C10, a second capacitor C20, and a comparator .

Although the principle of the present invention has been described in detail above in conjunction with the preferred embodiments of the present invention, those skilled in the art should understand that the above embodiments are only explanations for the exemplary implementation of the present invention, and are not intended to limit the scope of the present invention. The details in the embodiments do not constitute a limitation to the scope of the present invention. Without departing from the spirit and scope of the present invention, any obvious changes such as equivalent transformations and simple replacements based on the technical solutions of the present invention fall within the scope of the present invention. within the scope of protection.

Claims (9)

1. A safety detection device for a transformer, which is used to detect whether a transformer is leaking electricity, characterized in that: the safety detection device for a transformer includes: a main control unit (1), a leakage detection module (2), a leakage acquisition module (3), power-off protection module (4), alarm module (5), display module (6) and power module (7); the main control unit (1) is connected with the leakage detection module (2), The leakage collection module (3), the power failure protection module (4), the alarm module (5) are connected to the display module (6), and the leakage detection module (2) is connected to the leakage collection module (3) ; The power supply module (7) is directly or indirectly connected with the main control unit (1), the leakage detection module (2), the leakage collection module (3), the power-off protection module (4), the The alarm module (5) is connected to the display module (6) so as to supply power to each module, The safety detection device for a transformer also includes a jumper circuit, and the jumper circuit includes a first inductance L1, a second inductance L2, a first capacitor C1, a second capacitor C2, a potential difference resistor R1, and a single-pole bidirectional switch K1 , circuit breaker DL1, The positive pole of the high-voltage line is connected to the potential difference resistor R1, and is connected to the first end of the first capacitor C1 and the first end of the first inductor L1, and the other end of the potential difference resistor R1 is connected to the second end of the first capacitor C1, The first end of the second inductor L2, the second end of the first inductor L1 is connected to the first end of the second capacitor C2, the second end of the second capacitor C2 is connected to the second end of the second inductor L2, single-pole bidirectional switch One end of K1 is connected to the first end of the second capacitor C2, and the other two terminals A and B are respectively connected to two primary coils, primary coil 1 and primary coil 2, and the other ends of primary coil 1 and primary coil 2 are respectively connected to high-voltage lines the negative pole. 2. The safety detection device for a transformer according to claim 1, characterized in that: the jumper circuit is connected to the high voltage side of the transformer, one end of the jumper circuit is connected to the input end of the transformer, The other end is connected to the input end of the backup transformer. When the main control unit (1) detects a leakage accident, it controls the power-off protection module to disconnect the power-off protection module and drives the jumper The circuit closes, directing the high voltage input from the transformer to the backup transformer. 3. The safety detection device for transformers according to claim 1, characterized in that: the leakage acquisition module (3) includes a voltage transformer and a current transformer, and the voltage transformer and the current transformer are respectively Installed in the output circuit of the transformer, the outputs of the voltage transformer and the current transformer are respectively connected to the leakage detection module, and the leakage detection module measures the output voltage and the output voltage of the voltage transformer and the current transformer Output current. 4. The safety detection equipment for transformers according to claim 3, characterized in that: the safety detection equipment for transformers also includes a temperature detection module (8), the temperature detection module (8) and the connected to the main control unit (1). 5. The safety detection device for transformers according to claim 1, characterized in that: the main control unit is an AT89C1051 chip. 6. The safety detection device for transformers according to claim 1, characterized in that: the alarm module (5) is an alarm speaker. 7. The safety detection device for transformers according to claim 1, characterized in that: the display module (6) is a liquid crystal display. 8. The safety detection device for a transformer according to claim 1, characterized in that it further comprises a plurality of electroscopes, each electroscope is located at a detection point around the transformer. 9. The safety detection device for a transformer according to claim 8, characterized in that: the safety detection device further comprises a signal transmitter, and the signal transmitter sends an alarm signal to a remote server.