CN112595628B - Oilless anti-seismic remote sulfur hexafluoride gas density monitor - Google Patents

Abstract

The invention relates to the field of gas density monitoring and discloses an oilless anti-vibration remote sulfur hexafluoride gas density monitor which comprises a shell, a base, a Bardon tube, a locking contact signal shockproof mechanism, a bimetal element, a signal generator, a displacement amplifying mechanism and a density monitoring mechanism. When the density value changes, the barden tube and the bimetal element generate displacement, and the displacement is transmitted to the signal generator through the displacement amplifying mechanism, so that the signal generator sends out corresponding signals to complete the function of the density monitor, thereby overcoming the problem of low precision in the prior art and ensuring the advantages of high precision, good electrical performance, good contact point contact, long service life and the like of the density monitor.

Description

An oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor

Technical Field

The invention relates to the field of gas density monitoring, and in particular to an oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor.

Background technique

Sulfur hexafluoride electrical products have been widely used in the power sector, industrial and mining enterprises, and have promoted the rapid development of the power industry. Ensuring the reliable and safe operation of sulfur hexafluoride electrical products has become one of the important tasks of the power sector. The arc extinguishing medium and insulating medium of sulfur hexafluoride electrical products are sulfur hexafluoride gas, which cannot leak. If leakage occurs, the reliable and safe operation of sulfur hexafluoride electrical products cannot be guaranteed. Therefore, it is very necessary to monitor the sulfur hexafluoride density value of sulfur hexafluoride electrical products.

At present, a mechanical pointer-type sulfur hexafluoride gas density monitor (Figure 1) is generally used to monitor the density of sulfur hexafluoride gas. That is, when a sulfur hexafluoride electrical product leaks, the monitor can alarm and lock, and can also display the density value on site. The density monitor generally uses a dial 1, a pointer 2, a single Baden tube 3, a single bimetallic element 4, a base 5, a movement 6 and a hairspring-type magnetic-assisted electric contact 7. When the contact (alarm or lock) is closed, its closing force depends only on the tiny force of the contact hairspring. Even with the magnetic-assisted force, it is still very small, so it is extremely afraid of vibration, and the contact closure is not reliable enough. And the most important thing is that when it is oxidized or contaminated, the electric contact 7 often has poor contact, resulting in serious consequences. In addition, it is particularly emphasized that the magnetic-assisted electric contact has a slow breaking speed and a small contact capacity, resulting in a short service life. Therefore, it is difficult to guarantee the electrical performance and life of the density monitor. Once a problem occurs, the user can only replace it again, causing economic losses and failing to meet the requirements well. At the same time, the most important thing is that the mechanical SF6 gas density monitor currently used to monitor the density of SF6 gas has the following outstanding defects: 1) When a gas leak occurs in an SF6 electrical product, an alarm signal is issued only when its gas pressure drops to the alarm value, and at this time, a lot of SF6 gas has already leaked. For example, SF6 electrical equipment with a rated pressure of 0.6Mpa generally uses a density monitor with an alarm pressure of 0.52Mpa and a locking pressure of 0.50Mpa. Now many substations are unmanned substations. For such SF6 electrical equipment, if a gas leak occurs, the gas will drop from the rated pressure of 0.6Mpa to the alarm pressure of 0.52Mpa before the duty personnel discover it and notify the maintenance personnel to go to the scene to deal with the leakage accident, and at this time, a lot of SF6 gas has already leaked. Therefore, in unmanned substations, it is very necessary to monitor the density of SF6 electrical equipment online to detect gas leakage of SF6 electrical equipment in a timely manner. 2) The contacts of the density monitor generally use a hairspring-type magnetic auxiliary electric contact. When the contacts are closed, the closing force is very small and the contact closure is not reliable enough. Most importantly, when oxidized or contaminated, poor contact of the electrical contacts often occurs, resulting in failure and serious consequences. In addition, the circuit breaker of the electrical equipment needs to have a reclosing function, so the seismic resistance of the density monitor must be good. If not, the vibration caused by the circuit breaker operation will cause the locking contact of the density monitor to malfunction, resulting in the circuit breaker being unable to complete the reclosing.

Summary of the invention

The purpose of the present invention is to provide an oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor, which has high precision, good electrical performance, reliable contact points, good shock-resistant performance, no oil leakage, and has a density remote transmission function.

In order to achieve the above object, the present invention provides an oil-free, shock-resistant, remote transmission sulfur hexafluoride gas density monitor, comprising a housing, a connector connected to the housing is disposed on the outside of the housing, and a pointer and a dial for indicating the density value are also disposed inside the housing;

A base, the base being arranged inside the shell;

A bimetallic element, wherein the bimetallic element is disposed inside the housing;

A Baden tube, one end of which is fixedly connected to the base, and the other end of which is connected to one end of the bimetallic element through an end seat, and the Baden tube is connected to the joint through a conduit;

A signal generator, which is arranged on a base and has a contact operating handle;

The displacement amplification mechanism is a fan-shaped curved surface transmission mechanism, the starting end of which is transmission-connected to the other end of the bimetallic element, and the amplification end drives the contact operating handle to connect or disconnect the contact on the signal generator, and outputs alarm and locking contact signals;

A signal adjustment mechanism, wherein the signal adjustment mechanism is arranged inside the housing, and when the displacement amplifying mechanism rotates, the signal adjustment mechanism is driven to rotate, thereby triggering the contact of the signal generator to be disconnected or connected;

The locking contact anti-vibration mechanism is arranged in the housing near the starting end of the displacement amplification mechanism, and is used to limit the displacement amplification mechanism from moving too much. When the alarm point signal is activated, the starting end of the displacement amplification mechanism and the locking contact anti-vibration mechanism are in contact with each other.

A density monitoring mechanism is arranged inside the shell and is used to control and monitor the density of the sulfur hexafluoride gas and convert the density value into a current signal for long-distance transmission.

Preferably, the displacement amplification mechanism includes a central shaft connected to the rotating shaft of the pointer, two clamps arranged in parallel and at intervals on the base, a sector gear rotatably connected between the two clamps, and a central gear meshing with the sector gear and fixedly connected to the central shaft, the signal adjustment mechanism is arranged on the side of the central shaft opposite to the contact operating handle, and the radius of the sector gear is one third of the radius of the central gear.

Preferably, a rotating arm is provided on the non-gear side of the sector gear, the end of the rotating arm away from the sector gear is the starting end, a connecting rod is provided at the starting end, a connecting arm is provided at the end of the connecting rod away from the starting end, and the end of the connecting arm away from the connecting rod is connected to the other end of the bimetallic element.

Preferably, the locking contact anti-vibration mechanism comprises a fixing seat arranged in the housing and an elastic element arranged on the fixing seat, and the elastic element is arranged corresponding to the starting end of the transmission arm.

Preferably, a guide rail is provided on the fixing seat, a waist hole is provided on the elastic element, and the elastic element is fixed on the guide rail by screws passing through the waist hole.

Preferably, the density monitoring mechanism includes a pressure sensor, a temperature sensor, an amplifying circuit, an analog-to-digital converter, an embedded computer, a power module, an RS485 communication module, a digital-to-analog converter, a voltage-to-current converter, a current regulator, and a control module;

The gas density monitor collects pressure and temperature signals through a pressure sensor and a temperature sensor, processes them through an amplifying circuit, transmits them to an analog-to-digital converter, and then converts them into a gas density value through embedded computer software processing. The sulfur hexafluoride gas density value is transmitted over long distances through an RS485 communication module, thereby realizing online monitoring of the gas density of sulfur hexafluoride gas electrical equipment; and after the gas density value is processed by a digital-to-analog converter, a voltage-to-current converter, and a current regulator, the sulfur hexafluoride gas density value is converted into a current signal to realize long-distance transmission, thereby realizing online monitoring of the gas density of sulfur hexafluoride gas electrical equipment.

Preferably, the density monitoring mechanism further comprises a magnetic latching relay, an arc indicator and a pressure abnormality indicator;

When the gas density value obtained by the embedded computer exceeds the preset pressure abnormality threshold, the embedded computer drives the magnetic latching relay through the control module to activate the pressure abnormality indicator to send out pressure abnormality information; when the gas density value obtained by the embedded computer exceeds the preset arcing pressure threshold, the embedded computer drives the magnetic latching relay through the control module to activate the arcing indicator to send out arcing information.

Preferably, the density monitoring mechanism further comprises a humidity sensor and a dehumidifier;

The gas density monitor collects humidity signals through a humidity sensor, processes them through an amplifying circuit, transmits them to an analog-to-digital converter, and then processes them through an embedded computer. When the humidity signal value obtained by the embedded computer exceeds a preset humidity over-high threshold, the embedded computer drives the magnetic latching relay through a control module to activate the dehumidifier; and when the humidity signal value is lower than a preset humidity drop threshold, the embedded computer turns off the magnetic latching relay through the control module to stop the dehumidifier from working.

Preferably, the pressure sensor, temperature sensor, amplifier circuit, analog-to-digital converter, embedded computer, power module, RS485 communication module, and digital-to-analog converter each adopt an independent grounding method.

Preferably, the abnormal pressure indicator is an indicator light, an audible and visual alarm or an alarm horn.

The above technical solution has the following obvious advantages and characteristics compared with the prior art:

The displacement amplification mechanism controls the signal generator according to the size of the gas density value, so that the signal generator sends a corresponding signal to complete the function of the density monitor, thereby overcoming the problem of low precision of the prior art, ensuring the advantages of high precision, good electrical performance, good contact points, and long service life of the density monitor, and ensuring the reliable operation of the system. It is a sulfur hexafluoride gas density monitor with excellent performance, high precision, and good performance, which can be well applied to sulfur hexafluoride electrical equipment. At the same time, pressure sensors and temperature sensors are also used to collect pressure and temperature signals through pressure sensors and temperature sensors, and are converted into density values after being processed by embedded computers. After being processed by analog-to-digital converters, voltage-to-current converters, and current constants, the sulfur hexafluoride gas density value can be converted into a current signal to achieve long-distance transmission, thereby realizing online monitoring of the density of sulfur hexafluoride gas electrical equipment; and it can also be converted into a gas density value through embedded computer software processing, and the sulfur hexafluoride gas density value can be transmitted over long distances through the RS485 communication module, thereby realizing online monitoring of the gas density of sulfur hexafluoride gas electrical equipment. When the gas density monitored by the density monitor reaches the point where the alarm contact signal is activated, the displacement amplification mechanism contacts the locking contact anti-vibration mechanism, thereby improving the anti-vibration performance of the locking contact of the density monitor and preventing the vibration caused by the circuit breaker operation from causing the locking contact of the density monitor to malfunction, thereby enabling the circuit breaker to complete reclosing.

Other features and advantages of the present invention will be described in detail in the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

FIG1 shows a schematic structural diagram of a pointer-type sulfur hexafluoride gas density monitor of the prior art;

FIG2 shows a schematic structural diagram of an oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor according to the present invention;

FIG3 shows a side view of FIG2 of the present invention;

FIG4 shows a schematic diagram of the connection between the displacement amplification mechanism and the locking contact anti-vibration mechanism of the oil-free anti-vibration remote transmission sulfur hexafluoride gas density monitor of the present invention;

FIG. 5 is a schematic diagram showing the connection between the elastic element and the fixing seat of the locking contact anti-vibration mechanism of the present invention.

FIG6 shows a schematic structural diagram of a density monitoring mechanism of the oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor of the present invention.

Detailed ways

The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present invention, and is not used to limit the present invention.

2-6 , this embodiment discloses an oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor, comprising a housing 1 and a base 2 arranged inside the housing 1 , a bimetallic element 3 , a Baden tube 4 , an end seat 5 , a signal generator 6 , a contact operating handle 61 , a displacement amplification mechanism 7 , a signal adjustment mechanism 8 , a pointer 102 for indicating a density value and a dial 103 , a locking contact shock-proof mechanism 9 , and a density monitoring mechanism 10 arranged on the side of the housing 1 . The outer side of the housing 1 is provided with a joint 101 in communication therewith. The joint 101 is in communication with the Baden tube 4 through a conduit. One end of the Baden tube 4 is fixedly connected to the base 2, and the other end is connected to one end of the bimetallic element 3 through the end seat 5. The signal generator 6 is arranged on the base 2 and has a contact operating handle 61. Specifically, in this embodiment, the signal generator 6 is a micro switch, and three micro switches 601, 602, and 603 are arranged. The three micro switches 601, 602, and 603 correspond to an alarm contact, a switch-off locking contact, and a switch-on locking contact, respectively. The contact operating handle 61 is also provided with three corresponding ones, namely 611, 612, and 613, respectively. The signal adjustment mechanism 8 is also provided with three ones, namely 81, 82, and 83. The signal adjustment mechanism 81, 82, and 83 drives the contact operating handles 611, 612, and 613 according to the gas density value and the pressure value, so that the contacts on the micro switches 601, 602, and 603 are connected or disconnected. The contact of the micro switch 6 is connected to the terminal block through wires, and the terminal block is fixed on the housing 1. The outer side of the housing 1 is also provided with a watch glass 30 and a corresponding sealing ring, which can protect the internal structure of the housing 1 from mechanical damage and the intrusion of dirt and rainwater. The micro switch is also provided with a switch reinforcement mechanism, which can prevent the micro switch housing from breaking when the switch is opened and closed and generates strong vibration, and prevent the micro switch contact operating handle 61 from falling off, thereby greatly improving the vibration resistance of the monitor and ensuring reliable operation of the system.

The displacement amplification mechanism 7 is a fan-shaped curved surface transmission mechanism, whose starting end is transmission-connected to the other end of the bimetallic element 3, and the amplification end drives the contact operating handle 61 to connect or disconnect the contacts on the signal generator 6, and output alarm and locking contact signals. When the displacement amplification mechanism 7 rotates, it drives the signal adjustment mechanism 8 to rotate, thereby triggering the contacts of the signal generator 6 to disconnect or connect.

Please refer to FIG. 2 and FIG. 3 , specifically, the displacement amplification mechanism 7 includes a central shaft 71 that is transmission-connected to the rotating shaft 1021 of the pointer 102, two clamping plates 72 that are arranged on the base 2 in parallel and at intervals, a sector gear 73 that is rotationally connected between the two clamping plates 72, and a central gear 74 that is meshed with the sector gear 73 and fixedly connected to the central shaft 71. The signal adjustment mechanism 8 is arranged on the side of the central shaft 71 and is opposite to the contact operation handle 61. The radius of the sector gear 73 is one-third of the radius of the central gear 74. A rotating arm 731 is arranged on the non-gear side of the sector gear 73. The end of the rotating arm 731 that is away from the sector gear 73 is the starting end. The starting end is provided with a connecting rod 11. The end of the connecting rod 11 that is away from the starting end is provided with a connecting arm 12. The end of the connecting arm 12 that is away from the connecting rod 11 is connected to the other end of the bimetallic element 3. Specifically, the signal adjustment mechanism 8 is three eccentric wheels that are installed on the central shaft 71 at intervals. Since the radius of the sector gear 71 is three times smaller than the radius of the central gear 74, it can play a displacement amplification role. In the sulfur hexafluoride gas density monitor of this embodiment, since the signal generator 6 adopts a micro switch, and the control of the micro switch contacts is all controlled by the displacement amplifier mechanism 7 after amplification, the displacement is amplified by the displacement amplifier mechanism 7 to improve the accuracy and achieve a high-precision effect.

Please refer to Figure 4. The locking contact anti-vibration mechanism 9 is arranged in the housing 1 near the starting end of the displacement amplification mechanism 7, and is used to limit the displacement amplification mechanism 7 from moving too much. When the alarm point signal is activated, the starting end of the displacement amplification mechanism 7 and the locking contact anti-vibration mechanism 9 are in contact with each other. Specifically, the locking contact anti-vibration mechanism 9 includes a fixed seat 91 arranged in the housing 1 and an elastic element 92 arranged on the fixed seat 91. The elastic element 92 is arranged corresponding to the starting end of the transmission arm 731. Please refer to Figure 5. A guide rail 911 is arranged on the fixed seat 91, and a waist hole 921 is arranged on the elastic element 92. The elastic element 92 is fixed to the guide rail 911 by passing a screw 93 through the waist hole 921. Preferably, the elastic element 92 is L-shaped and can be made of a manganese steel sheet or a phosphor copper sheet. When the gas density monitored by the density monitor reaches the alarm contact signal, the transmission arm 731 and the elastic element 92 are in contact with each other.

When the vibration caused by the operation of the _SF6 circuit breaker is transmitted to the density monitor, the Baden tube 4 and the bimetallic element 3 of the density monitor will be displaced, and then transmitted to the transmission arm 731 through the connecting rod 11, causing the transmission arm 731 to swing back and forth. When the transmission arm 731 swings beyond the position corresponding to the action of the gas density monitor alarm contact, the elastic element 92 will contact the starting end of the transmission arm 731, preventing the transmission arm 731 from moving in the direction corresponding to the action of the gas density monitor locking contact, greatly improving the anti-seismic performance of the density monitor locking contact, making it difficult for the vibration caused by the operation of the _SF6 circuit breaker to cause the locking contact of the density monitor to malfunction, enabling the circuit breaker to complete the reclosing function and ensure the full performance of the power supply. Since the locking contact signal anti-seismic mechanism 9 mainly includes the elastic element 92 and the fixing seat 91, its structure cost is low and very simple. The simpler it is, the more reliable it is, and it is also very conducive to production, and the anti-seismic effect is very good.

After comparative tests, for the same density monitor, without the locking contact signal shockproof mechanism 9, for example, for a density monitor with a rated parameter of 0.6MPa, an alarm pressure of 0.53MPa, and a locking pressure of 0.50MPa, when the density monitor's gas pressure is 0.57MPa, in an impact test with an impact amplitude of 50g and a duration of 11ms, the locking contact (0.50MPa) of the density monitor will malfunction, making it difficult to meet the reclosing requirements of the circuit breaker. For the same density monitor, if the locking contact signal shockproof mechanism 9 is added, that is, for a density monitor with a rated parameter of 0.6MPa, an alarm pressure of 0.53MPa, and a locking pressure of 0.50MPa, when the density monitor's gas pressure drops to 0.53MPa, in an impact test with an impact amplitude of 50g and a duration of 11ms, the locking contact (0.50MPa) of the density monitor will not malfunction, thus meeting the reclosing requirements of the circuit breaker. Therefore, the locking contact signal anti-vibration mechanism 9 is added. Such an innovative design greatly improves the anti-vibration performance. At the same time, the cost is very good, it is also very reliable, and it is conducive to production and large-scale promotion. At the same time, there is no need to fill oil, and there will be no oil leakage problem, which is of great significance. In order to further improve the anti-vibration performance of the density monitor, a vibration-proof pad is provided on the shell 1. To solve the influence of the temperature difference problem, the outer surface of the shell 1 is wrapped with an insulation layer.

When the gas density value changes, the Baden tube 4 and the bimetallic element 3 are displaced, and the displacement is transmitted to the starting end of the displacement amplification mechanism 7 through the connecting rod 11. The amplification end (central axis 71) of the displacement amplification mechanism 7 is connected to the contact operating handles 611, 612, 613 of the micro switches 601, 602, 603 through the signal adjustment mechanisms 81, 82, 83. The contact operating handles 611, 612, 61 are driven according to the gas density value and the pressure value to connect or disconnect the contacts on the micro switches 601, 602, 603, so that the micro switches send corresponding signals to complete the function of the density monitor.

The sulfur hexafluoride gas density monitor of the present invention is based on the Baden tube 4, and uses the bimetallic element 3 to correct the changing pressure and temperature to reflect the change of the sulfur hexafluoride gas density. That is, under the pressure of the sulfur hexafluoride gas to be measured, due to the action of the bimetallic element 3, the change of its density value and the corresponding change of the pressure value force the end of the Baden tube 4 to produce corresponding elastic deformation-displacement, which is transmitted to the central axis 71 of the displacement amplification mechanism 7 by means of the bimetallic element 3 and the connecting rod 11, and the central axis 71 is transmitted to the pointer 102, so that the measured sulfur hexafluoride gas density value is indicated on the dial 103. If there is a gas leak, its density value drops to a certain level (reaching the alarm or lockout value), the Baden tube 4 produces a corresponding downward displacement, and through the bimetallic element 3, the connecting arm 12 is displaced downward and transmitted to the connecting rod 11, the connecting rod 11 transmits it to the displacement amplification mechanism 7, the sector gear 73 transmits it to the central shaft 71 and amplifies it, and the central shaft 71 drives the corresponding signal adjustment mechanism 81, 82, 83 to rotate. When it reaches a certain level, the signal adjustment mechanism 81, 82, 83 triggers the contact operating handle 611, 612, 613 of the corresponding micro switch 601, 602, 603, and the corresponding micro switch 601, 602, 603 contact is connected, and the corresponding signal (alarm or lockout) is issued, so as to monitor and control the sulfur hexafluoride gas density in the electrical switch and other equipment, so that the electrical equipment can work safely. If the density value increases, the pressure value also increases accordingly. When it increases to a certain level, the Baden tube 4 also produces a corresponding upward displacement. Through the bimetallic element 3, the connecting arm 12 is displaced upward and transmitted to the connecting rod 11. The connecting rod 11 transmits it to the displacement amplification mechanism 7, and the fan gear 73 transmits it to the central shaft 71. The signal adjustment mechanisms 81, 82, and 83 rotate. When it reaches a certain level, the signal adjustment mechanisms 81, 82, and 83 do not trigger the contact operating handles 611, 612, and 613 of the corresponding micro switches 601, 602, and 603, and the corresponding micro switches 601, 602, and 603 contacts are disconnected, and the signal (alarm or lockout) is released.

The density monitoring mechanism 10 is disposed inside the housing 1 and is used to control and monitor the density of the sulfur hexafluoride gas and convert the density value into a current signal for long-distance transmission.

The density monitoring mechanism 10 includes a pressure sensor 13, a temperature sensor 14, an amplifier circuit 15, an analog-to-digital converter 16, an embedded computer 17, a power module 18, an RS485 communication module 19, a digital-to-analog converter 20, a voltage-to-current converter 21, a current regulator 22, a control module 23, a magnetic latching relay 24, an arc indicator 25, a pressure abnormality indicator 26, a humidity sensor 27 and a dehumidifier 28.

The temperature sensor 14 is sealed and fixed on the right side of the base 2, and the temperature sensor 14 is in contact with the sulfur hexafluoride gas, so the temperature value of the sulfur hexafluoride gas can be accurately measured. The pressure sensor 13 is sealed and fixed on the back of the base 2, and the amplifier circuit 15, the embedded computer 17, the power module 18, the analog-to-digital converter 16, the RS485 communication module 19, the digital-to-analog converter 20, the voltage-to-current converter 21, and the current regulator 22 are all fixed on the printed circuit board 31, and the printed circuit board 31 is located behind the base 2 and behind the housing 1. The amplifier circuit 15, the embedded computer 17, the power module 18, the analog-to-digital converter 16, the voltage-to-current converter 21, and the current regulator 22 are located around the pressure sensor 13, and the dehumidifier 28 is arranged at the lower part of the outer shell 1.

The gas density monitor collects pressure and temperature signals through the pressure sensor 13 and the temperature sensor 14, processes them through the amplifying circuit 15, transmits them to the analog-to-digital converter 16, and then converts them into gas density values through the software processing of the embedded computer 17. The sulfur hexafluoride gas density value is transmitted over long distances through the RS485 communication module 19, thereby realizing online monitoring of the gas density of sulfur hexafluoride gas electrical equipment; and, after the gas density value is processed by the digital-to-analog converter 20, the voltage-to-current converter 21 and the current regulator 22, the sulfur hexafluoride gas density value is converted into a current signal to realize long-distance transmission, thereby realizing online monitoring of the gas density of sulfur hexafluoride gas electrical equipment.

When the gas density value obtained by the embedded computer 17 exceeds the set predetermined pressure abnormality threshold, the embedded computer 17 drives the magnetic holding relay 24 to operate through the control module 23, so that the pressure abnormality indicator 26 is activated to send out pressure abnormality information; when the gas density value obtained by the embedded computer 17 exceeds the set predetermined arcing pressure threshold, the embedded computer 17 drives the magnetic holding relay 24 to operate through the control module 23, so that the arcing indicator 25 is activated to send out arcing information.

The gas density monitor collects humidity signals through the humidity sensor 27, processes them through the amplifying circuit 15, transmits them to the analog-to-digital converter 16, and then processes them through the embedded computer 17. When the humidity signal value obtained by the embedded computer 17 exceeds the preset humidity over-high threshold, the embedded computer 17 drives the magnetic latching relay 24 to operate through the control module 23, so that the dehumidifier 28 operates; and when the humidity signal value is lower than the preset humidity drop threshold, the embedded computer 17 turns off the magnetic latching relay 24 through the control module 23, so that the dehumidifier 28 stops working.

The working principle or steps are as follows: the pressure and temperature are measured by the pressure sensor 13 and the temperature sensor 14, and the measured pressure and temperature signals are amplified by the amplifier circuit 15. The amplified pressure and temperature signals are processed by the digital-to-analog converter 20 to convert the pressure and temperature values into corresponding digital signals of pressure and temperature, which are then collected by the embedded computer 17 and calculated by the embedded computer 17 to obtain the sulfur hexafluoride gas density _P20 . The sulfur hexafluoride gas density _P20 is converted by the analog-to-digital converter 16 to a voltage signal _P20U , and then converted by the voltage-to-current converter 21 to convert the voltage signal _P20U into a current signal _P20I . After the current constant current 22, the sulfur hexafluoride gas density _P20I of the current signal can be transmitted over a long distance, thereby realizing online monitoring of the density of sulfur hexafluoride gas electrical equipment. Furthermore, the gas density value P 20 can be converted into a gas density value P ₂₀ through software processing of the embedded computer 17 , and then the sulfur hexafluoride gas density value P ₂₀ can be transmitted over long distances through the RS485 communication module 19 , thereby realizing online monitoring of the gas density P ₂₀ of sulfur hexafluoride gas electrical equipment.

In addition, when the gas density value _P20 obtained by the embedded computer 17 exceeds the preset pressure abnormality threshold value PYC, the embedded computer 17 drives the magnetic latching relay 24 to operate through the control module 23, so that the pressure abnormality indicator 26 operates to send out pressure abnormality information. The pressure abnormality indicator 26 may include but is not limited to a red indicator light, an audible and visual alarm, and an alarm horn. That is, when the pressure is abnormal, the staff is reminded in time that a fault has occurred and corresponding measures should be taken, such as reminding the staff not to approach the equipment with problems. When the gas density value _P20 obtained by the embedded computer 17 exceeds the preset arcing pressure threshold value PRH, the embedded computer 17 drives the magnetic latching relay 24 to operate through the control module 23, so that the arcing indicator 25 operates to send out arcing information, so that the staff knows that the electrical equipment has arced and needs to be handled and repaired in time.

The gas density monitor collects humidity signals through the humidity sensor 27, processes them through the amplifier circuit 15, transmits them to the analog-to-digital converter 16, and then processes them through the embedded computer 17. When the humidity signal value PH obtained by the embedded computer 17 exceeds the preset humidity over-high threshold PHG, the embedded computer 17 drives the magnetic latching relay 24 to operate through the control module 23, so that the dehumidifier 28 operates to reduce the humidity of the density monitor and ensure its insulation performance; and when the humidity signal value PH is lower than the preset humidity drop threshold PHX, the embedded computer 17 turns off the magnetic latching relay 24 through the control module 23 to stop the dehumidifier 28 from working.

In addition, in order to improve the anti-electromagnetic interference capability of the density monitor, as shown in FIG6 , the pressure sensor 13, the temperature sensor 14, the humidity sensor 27, the amplifier circuit 15, the analog-to-digital converter 16, the embedded computer 17, the power module 24, the RS485 communication module 33, and the digital-to-analog converter 20 each adopt an independent grounding method, so that after each loop is grounded, the current in each loop is introduced into the ground to avoid electromagnetic interference, thereby improving the anti-electromagnetic interference performance of the density monitor and ensuring the reliable operation of the density monitor.

In summary, the sulfur hexafluoride gas density monitor of this embodiment uses a displacement amplification mechanism 7 to amplify the displacement, which greatly improves the accuracy of the density monitor. At the same time, a pressure sensor 13 and a temperature sensor 14 are used to collect pressure and temperature signals, which are converted into density values after being processed by an embedded computer 17. After being processed by an analog-to-digital converter 16, a voltage-to-current converter 21 and a current regulator 22, the sulfur hexafluoride gas density value can be converted into a current signal (4-20 mA) to achieve long-distance transmission, thereby realizing online monitoring of the density of sulfur hexafluoride gas electrical equipment. In addition, since the signal generator 6 of the density monitor uses a micro switch, and the control of the micro switch contacts is all controlled by the displacement amplification mechanism 7 after amplification, the purpose is to improve the accuracy and achieve a high-precision effect, so the accuracy is high, the electrical performance of the contacts is good, the service life is long, and the temperature compensation performance is more accurate.

The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, and these simple modifications all belong to the protection scope of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims (4)

1. An oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor, comprising: A housing (1), wherein a joint (101) in communication with the housing (1) is disposed on the outside of the housing (1), and a pointer (102) and a dial (103) for indicating a density value are also disposed inside the housing (1); A base (2), wherein the base (2) is arranged inside the shell (1); A bimetallic element (3), wherein the bimetallic element (3) is arranged inside the housing (1); A Baden tube (4), one end of the Baden tube (4) is fixedly connected to the base (2), and the other end is connected to one end of the bimetallic element (3) via an end seat (5), and the Baden tube (4) is connected to the joint (101) via a conduit; A signal generator (6), the signal generator (6) being arranged on the base (2) and having a contact operating handle (61); A displacement amplification mechanism (7), the displacement amplification mechanism (7) being a fan-shaped curved surface transmission mechanism, the starting end of which is transmission-connected to the other end of the bimetallic element (3), and the amplification end drives the contact operating handle (61) to connect or disconnect the contacts on the signal generator (6), thereby outputting alarm and locking contact signals; A signal adjustment mechanism (8), wherein the signal adjustment mechanism (8) is arranged inside the housing (1), and when the displacement amplification mechanism (7) rotates, the signal adjustment mechanism (8) is driven to rotate, thereby triggering the contact of the signal generator (6) to be disconnected or connected; a locking contact anti-vibration mechanism (9), the locking contact anti-vibration mechanism (9) being arranged in the housing (1) near the starting end of the displacement amplification mechanism (7) and being used to limit excessive movement of the displacement amplification mechanism (7); when the alarm point signal is actuated, the starting end of the displacement amplification mechanism (7) and the locking contact anti-vibration mechanism (9) are in contact with each other; A density monitoring mechanism (10), the density monitoring mechanism (10) being arranged inside the housing (1) and used for controlling and monitoring the density of the sulfur hexafluoride gas and converting the density value into a current signal for long-distance transmission; The displacement amplification mechanism (7) comprises a central shaft (71) drivingly connected to the rotating shaft (1021) of the pointer (102), two clamping plates (72) arranged on the base (2) in parallel and at intervals, a sector gear (73) rotatably connected between the two clamping plates (72), and a central gear (74) meshing with the sector gear (73) and fixedly connected to the central shaft (71), the signal adjustment mechanism (8) being arranged on the side of the central shaft (71) opposite to the contact operating handle (61), and the radius of the sector gear (73) being one third of the radius of the central gear (74); A rotating arm (731) is provided on the non-gear side of the sector gear (73); an end of the rotating arm (731) away from the sector gear (73) is a starting end; a connecting rod (11) is provided on the starting end; an end of the connecting rod (11) away from the starting end is provided with a connecting arm (12); an end of the connecting arm (12) away from the connecting rod (11) is connected to the other end of the bimetallic element (3); The locking contact anti-vibration mechanism (9) comprises a fixing seat (91) arranged in the housing (1) and an elastic element (92) arranged on the fixing seat (91); the elastic element (92) is arranged corresponding to the starting end of the rotating arm (731). 2. The oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor according to claim 1, characterized in that a guide rail (911) is provided on the fixing seat (91), a waist hole (921) is provided on the elastic element (92), and the elastic element (92) is fixed to the guide rail (911) by means of a screw (93) passing through the waist hole (921). 3. The oil-free, anti-vibration, remote-transmission sulfur hexafluoride gas density monitor according to claim 1, characterized in that the density monitoring mechanism (10) comprises a pressure sensor (13), a temperature sensor (14), an amplifier circuit (15), an analog-to-digital converter (16), an embedded computer (17), a power module (18), an RS485 communication module (19), a digital-to-analog converter (20), a voltage-to-current converter (21), a current regulator (22), and a control module (23); The gas density monitor collects pressure and temperature signals through a pressure sensor (13) and a temperature sensor (14), processes the signals through an amplifying circuit (15), transmits the signals to an analog-to-digital converter (16), and converts the signals into gas density values through software processing of an embedded computer (17). The sulfur hexafluoride gas density values are transmitted over long distances through an RS485 communication module (19), thereby realizing online monitoring of the gas density of sulfur hexafluoride gas electrical equipment; After the gas density value is processed by a digital-to-analog converter (20), a voltage-to-current converter (21) and a current regulator (22), the sulfur hexafluoride gas density value is converted into a current signal to achieve long-distance transmission, thereby achieving online monitoring of the gas density of sulfur hexafluoride gas electrical equipment. 4. The oil-free, shock-resistant, remote-transmission sulfur hexafluoride gas density monitor according to claim 3, characterized in that the pressure sensor (13), the temperature sensor (14), the amplifier circuit (15), the analog-to-digital converter (16), the embedded computer (17), the power module (18), the RS485 communication module (19), and the digital-to-analog converter (20) each adopt an independent grounding method.