阅读说明：本技术 箱体密封状态监测与评估方法及监测系统 (Box body sealing state monitoring and evaluating method and monitoring system ) 是由 李作鑫 蔡新环 孙文龙 林祥礼 杨东军 郭吉顺 于 2021-01-04 设计创作，主要内容包括：本发明涉及一种箱体密封状态监测与评估方法,通过监测箱内气压变化对箱体密封状态进行初步评估：设置标准温度补偿曲线P＝P(T)；设置箱内正常工作温度变化范围[T1,T2],当箱内温度超过箱内正常工作温度变化范围时,将箱内温度调至正常工作温度变化范围[T1,T2]内；设置外部环境评估阈值X,结合标准温度补偿曲线P＝P(T)确定标准气压补偿区[P(T)-X,P(T)+X]；设置标准时间间隔Δt,当测得的箱内气压P＞P(T)+X或P＜P(T)-X对应的超压时间t≤Δt时,测得的箱内气压视为气压正常状态。同时,进一步综合箱内气压、湿度、灰尘浓度指标,以保证对箱体密封性判断的准确性,避免对箱体密封性产生误判。同时,本发明还提供了相应的箱体密封状态监测系统,以实现对箱体的密封性监测。(The invention relates to a method for monitoring and evaluating the sealing state of a box body, which carries out preliminary evaluation on the sealing state of the box body by monitoring the change of air pressure in the box: setting a standard temperature compensation curve P ═ P (T); setting a normal working temperature variation range [ T1, T2] in the box, and adjusting the temperature in the box to be within the normal working temperature variation range [ T1, T2] when the temperature in the box exceeds the normal working temperature variation range in the box; setting an external environment evaluation threshold value X, and determining a standard air pressure compensation area [ P (T) -X, P (T) + X ] by combining a standard temperature compensation curve P ═ P (T); setting a standard time interval delta t, and when the overpressure time t corresponding to the measured air pressure P in the box is more than P (T) + X or P (P) (T) -X is less than or equal to delta t, determining the measured air pressure in the box as the normal state of the air pressure. Meanwhile, the indexes of air pressure, humidity and dust concentration in the box are further combined, so that the accuracy of box body sealing judgment is ensured, and the misjudgment of the box body sealing is avoided. Meanwhile, the invention also provides a corresponding box body sealing state monitoring system to realize the sealing monitoring of the box body.)

1. The utility model provides a box body sealing condition monitoring and aassessment method, includes and carries out preliminary aassessment to box body sealing condition through monitoring incasement air pressure change, specifically is:

setting a standard temperature compensation curve P ═ P (T), wherein: p is the air pressure in the tank, T is the temperature in the tank;

setting a normal working temperature variation range [ T1, T2] in the box, and adjusting the temperature in the box to be within the normal working temperature variation range [ T1, T2] when the temperature in the box exceeds the normal working temperature variation range in the box, wherein T1 and T2 are a lower limit value and an upper limit value of the normal working temperature respectively;

setting an external environment evaluation threshold value X, determining a standard air pressure compensation area [ P (T) -X, P (T)) + X by combining a standard temperature compensation curve P ═ P (T), and considering that the air pressure in the box is normal when the measured air pressure P in the box changes in the interval of the standard air pressure compensation area [ P (T) -X, P (T)) + X ];

setting a standard time interval delta t, and when the overpressure time t corresponding to the measured air pressure P in the box is more than P (T) + X or P (P) (T) -X is less than or equal to delta t, determining the measured air pressure in the box as the normal state of the air pressure.

2. The box sealing state monitoring and evaluating method according to claim 1, wherein an ideal gas state equation is adoptedAnd determining a standard temperature compensation curve P ═ P (T), wherein C is a constant, P is the air pressure in the box, V is the volume of the box body, and T is the temperature in the box.

3. The box sealing state monitoring and evaluating method according to claim 1 or 2, further comprising evaluating the box sealing state by monitoring the dust concentration in the box: and setting a box dust concentration threshold value A according to the requirement of the protection grade of the box body, and judging that the dust concentration is too high when the measured dust concentration in the box exceeds the box dust concentration threshold value A, and giving an alarm on the dust concentration in the box.

4. The box sealing state monitoring and evaluating method according to claim 3, further comprising evaluating the box sealing state by monitoring the humidity inside the box: according to the requirement of the protection level of the box body, a box body humidity threshold value B is set, when the humidity in the box body exceeds the box body humidity threshold value B, the humidity is judged to be too high, and the humidity in the box body is alarmed.

5. The cabinet sealing state monitoring and evaluating method according to claim 4, wherein the priority of the air pressure in the cabinet is set higher than the priority of the humidity and the dust concentration, and when the air pressure in the cabinet exceeds the standard, the cabinet sealing state is further judged according to the humidity and the dust concentration of the cabinet:

when the air pressure in the box exceeds the standard and the humidity and the dust concentration are normal, primary alarm is carried out, the detection result cannot completely judge that the box body is sealed and invalid, the fault condition is recorded, and the tightness of the box body is further detected;

when the air pressure in the box exceeds the standard and the humidity or the dust concentration exceeds the standard, performing secondary alarm, judging that the sealing performance of the box body is invalid, and performing corresponding dehumidification or dust removal treatment on the box body according to a detection result;

when the air pressure, the humidity and the dust concentration in the box exceed the standard, three-level alarm is carried out, the sealing failure of the box body is judged, and the box body is subjected to dehumidification and dust removal simultaneously.

6. The box sealing state monitoring and evaluating method according to claim 5, wherein when the air pressure in the box is normal, no matter whether the humidity and the dust concentration exceed the standards, the box sealing performance is judged to be effective, no alarm processing is performed, and the box is subjected to corresponding dehumidification or dust removal processing according to the detection result.

7. A box body sealing state monitoring system is characterized in that a temperature sensor, a temperature adjusting device, an air pressure sensor, a humidity sensor and a dust concentration sensor are arranged in a box, the temperature sensor, the temperature adjusting device, the air pressure sensor, the humidity sensor and the dust concentration sensor are all connected to a processor, and the temperature sensor, the air pressure sensor, the humidity sensor and the dust concentration sensor respectively detect temperature, air pressure, humidity and dust concentration information in the box and feed back the information to the processor; the processor determines the sealing state of the box according to the box sealing state monitoring and evaluating method of any one of claims 1 to 6, and controls the temperature adjusting device to work when the temperature in the box is abnormal, so as to adjust the temperature in the box to return to a normal temperature range.

Technical Field

The invention belongs to the technical field of sealing monitoring, and particularly relates to a box body sealing state monitoring and evaluating method and a box body sealing state monitoring system.

Background

The leakproofness is the important guarantee of product safe and reliable, for example all kinds of electric boxes that are equipped with in the rail vehicle, like the battery box under the car and the high-pressure tank of charging case, roof etc. the box is inside to have a large amount of electrical components usually, and is higher to box leakproofness requirement, in case the box is sealed not can satisfy the design requirement or the box is sealed to be destroyed, and foreign matter such as dust and vapor gets into inside the box very easily. Dust has dust particle charge property and is easy to condense and settle around the electric part, so that the insulation strength of the electric part is damaged, and poor contact and even short circuit of the electric part are caused; the excessive humidity in the box body can reduce the insulating property of electrical equipment and cause the corrosion of electrical parts and box body metal parts, and the risk of flashover discharge, breakdown and even burning of high-voltage products can also occur.

However, the existing electric equipment of the rail vehicle is not provided with a box body sealing state detection device, and only after the production of the product is finished, a water spraying test, a dust test or a negative pressure pumping test is carried out to test the sealing effect before delivery. After the product is loaded, the sealing effect of the box body can be roughly checked only by utilizing the overhauling and maintaining opportunities in a certain period, and whether ash or water enters or not is determined. Because the overhaul maintenance cycle of equipment is long, can not discover in time, handle the sealed problem of box, very easily lead to the product trouble to appear the potential safety hazard.

Therefore, the invention considers and designs a box body sealing state monitoring system and an evaluation method, and carries out sealing state monitoring on the closed box body so as to carry out a corresponding alarm mechanism and determine a processing scheme.

Disclosure of Invention

The invention provides a method and a system for monitoring and evaluating the sealing state of a box body aiming at the sealing requirement of the box body, and the method and the system form an integral sealing judgment scheme by comprehensively considering index requirements such as air pressure, humidity, dust concentration and the like in the box body so as to judge the sealing state of the box body and ensure the accuracy of judging the sealing state of the box body.

In order to achieve the above object, the present invention provides a method for monitoring and evaluating a sealing state of a tank, including the step of performing preliminary evaluation on the sealing state of the tank by monitoring a change in air pressure in the tank, specifically:

setting a standard temperature compensation curve P ═ P (T), wherein: p is the air pressure in the tank, T is the temperature in the tank;

setting a normal working temperature variation range [ T1, T2] in the box, and adjusting the temperature in the box to be within the normal working temperature variation range [ T1, T2] when the temperature in the box exceeds the normal working temperature variation range in the box, wherein T1 and T2 are a lower limit value and an upper limit value of the normal working temperature respectively;

setting an external environment evaluation threshold value X, determining a standard air pressure compensation area [ P (T) -X, P (T)) + X by combining a standard temperature compensation curve P ═ P (T), and considering that the air pressure in the box is normal when the measured air pressure P in the box changes in the interval of the standard air pressure compensation area [ P (T) -X, P (T)) + X ];

setting a standard time interval delta t, and when the overpressure time t corresponding to the measured air pressure P in the box is more than P (T) + X or P (P) (T) -X is less than or equal to delta t, determining the measured air pressure in the box as the normal state of the air pressure.

Preferably, an ideal gas state equation is adoptedAnd determining a standard temperature compensation curve P ═ P (T), wherein C is a constant, P is the air pressure in the box, V is the volume of the box body, and T is the temperature in the box.

Preferably, the method for monitoring and evaluating the sealing state of the box body further comprises the following steps of evaluating the sealing state of the box body by monitoring the dust concentration in the box body: and setting a box dust concentration threshold value A according to the requirement of the protection grade of the box body, and judging that the dust concentration is too high when the measured dust concentration in the box exceeds the box dust concentration threshold value A, and giving an alarm on the dust concentration in the box.

Preferably, the method for monitoring and evaluating the sealing state of the box body further comprises the following steps of evaluating the sealing state of the box body by monitoring the humidity in the box body: according to the requirement of the protection level of the box body, a box body humidity threshold value B is set, when the humidity in the box body exceeds the box body humidity threshold value B, the humidity is judged to be too high, and the humidity in the box body is alarmed.

Preferably, the priority that sets up the incasement air pressure is higher than the priority of humidity and dust concentration, and when the incasement air pressure superscript, further according to box humidity and dust concentration, judge box encapsulated situation:

when the air pressure in the box exceeds the standard and the humidity and the dust concentration are normal, primary alarm is carried out, the detection result cannot completely judge that the box body is sealed and invalid, the fault condition is recorded, and the tightness of the box body is further detected;

when the air pressure in the box exceeds the standard and the humidity or the dust concentration exceeds the standard, performing secondary alarm, judging that the sealing performance of the box body is invalid, and performing corresponding dehumidification or dust removal treatment on the box body according to a detection result;

when the air pressure, the humidity and the dust concentration in the box exceed the standard, three-level alarm is carried out, the sealing failure of the box body is judged, and the box body is subjected to dehumidification and dust removal simultaneously.

Preferably, when the air pressure in the box is normal, whether the humidity and the dust concentration exceed the standard or not, the tightness of the box body is judged to be effective, the alarm processing is not carried out, and the box body is correspondingly dehumidified or dedusted according to the detection result.

The invention also provides a box body sealing state monitoring system, wherein a temperature sensor, a temperature adjusting device, an air pressure sensor, a humidity sensor and a dust concentration sensor are arranged in the box, the temperature sensor, the temperature adjusting device, the air pressure sensor, the humidity sensor and the dust concentration sensor are all connected to a processor, and the temperature sensor, the air pressure sensor, the humidity sensor and the dust concentration sensor respectively detect the temperature, the air pressure, the humidity and the dust concentration information in the box and feed back the information to the processor; and the processor determines the sealing state of the box body according to the box body sealing state monitoring and evaluating method, and controls the temperature adjusting device to work when the temperature in the box body is abnormal, so that the temperature in the box body is adjusted to be restored to a normal temperature range.

Compared with the prior art, the invention has the advantages and positive effects that:

the invention provides a method for monitoring and evaluating the sealing state of a box body, which takes the air pressure in the box body as a main index for judging whether the sealing property of the box body is invalid or not, carries out preliminary evaluation on the sealing state of the box body by monitoring the change of the air pressure in the box body, and carries out three different compensation schemes of temperature compensation, external environment compensation, overpressure time compensation and the like according to the influence of different factors so as to ensure the readiness for judging the air pressure of the box body and avoid the misjudgment on the sealing property of the box body. Meanwhile, on the basis of monitoring of the air pressure in the box, the humidity and the dust concentration in the box are further increased to serve as secondary indexes, the air pressure, the humidity and the dust concentration in the box are comprehensively considered, an integral tightness judgment scheme is formed, different alarm modes are set to judge whether the sealing state of the box is invalid or not, the accuracy of judgment of the tightness of the box is guaranteed, and meanwhile, a corresponding processing mode is made according to a detection result. Meanwhile, the invention also provides a corresponding box body sealing state monitoring system to realize the sealing monitoring of the box body.

Drawings

FIG. 1 is a flowchart of the overall method for monitoring and evaluating the sealing state of a box according to the present invention;

FIG. 2 is a graph of the pressure in the tank versus temperature and time compensation.

Detailed Description

The following further describes embodiments of the present invention with reference to the accompanying drawings.

The embodiment of the invention provides a method for monitoring and evaluating the sealing state of a box body, which is used for monitoring the sealing performance of box body equipment in a railway vehicle, such as a storage battery box, a charging machine box and a high-pressure box on the top of the vehicle, and mainly carries out comprehensive evaluation by detecting the air pressure, the humidity and the dust concentration in the box body. The dynamic change of the air pressure in the box is the best visual embodiment of the good and bad tightness of the box body, and the sealing state of the box body is preliminarily evaluated by monitoring the change of the air pressure in the box. When the box body is sealed and has a problem, because the pressure difference between the inside and the outside of the box body leads to water vapor, dust and the like to enter the box body, the sealing state of the box body is further confirmed by combining the detection of the humidity and the dust concentration in the box body, whether the humidity and the dust concentration in the box body exceed the standard or not due to the sealing of the box body is confirmed, and whether the influence is caused on the normal work of each electric device in the box body or whether the maintenance is needed or not is confirmed.

As shown in fig. 1, the method for monitoring and evaluating the sealing state of the box provided by this embodiment specifically includes:

(1) preliminary assessment is carried out to box sealing state through monitoring incasement gas pressure change, including temperature compensation, external environment influence compensation, superpressure time compensation triplex, specifically do:

the detection of the air pressure in the box is the most important index for judging whether the sealing performance of the box body fails or not, when the sealing performance of the box body is poor, the air pressure in the box can fluctuate greatly, the fluctuation of the air pressure can not only cause the reduction of the insulating performance, but also influence the heat conduction effect of the air to cause the rise of the temperature in the box body. Since the running environment of the vehicle body, the temperature in the tank, the terrain and the like all affect the air pressure in the tank, corresponding compensation is needed to be carried out for discharging the influence of external conditions.

Temperature compensation:

in the closed box, the higher the temperature is, the larger the air pressure is, and the ideal gas state equation is adopted in the embodimentA standard temperature compensation curve P ═ P (T) is determined as shown in fig. 2, where C is a constant, P is the tank interior air pressure, V is the tank volume, and T is the tank interior temperature.

Determining the normal working temperature variation range [ T1, T2] in the box according to the working temperature requirement in the box and the environment temperature when the train operates, adjusting the temperature in the box to be within the normal working temperature variation range [ T1, T2] when the temperature in the box exceeds the normal working temperature variation range in the box, and performing temperature compensation, wherein T1 and T2 are the lower limit value and the upper limit value of the normal working temperature respectively.

When the box body is in a high-temperature environment or an electric component in the box body works and generates heat, the temperature in the box body rises; and in a high and cold environment, the temperature in the box body is reduced. Because the temperature in the box has great influence on the air pressure, the temperature compensation is carried out when the air pressure detection and evaluation are carried out, so that the problems of false alarm and missing report caused by fluctuation in the box can be avoided. In this embodiment, the temperature sensor and the temperature adjusting device are arranged in the box, and the temperature sensor monitors the temperature in the box in real time and feeds the temperature back to the processor. When the temperature in the box exceeds the standard, the processor sends a signal to control the temperature adjusting device to work, and the adjustment of the temperature in the box is completed, so that the temperature in the box is restored to a normal temperature range, the normal temperature required by the operation of a product is ensured, and meanwhile, the accuracy of monitoring the sealing state of the box body is also ensured.

External environmental impact compensation:

during the running process of the train, the running speed of the train, the external air pressure and the like can cause slight changes of the air pressure in the box, so that the air pressure monitoring result slightly fluctuates. And (3) setting an external environment evaluation threshold value X according to the actual box body test condition and the operating environment, determining a standard air pressure compensation area [ P (T) -X, P (T) + X) by combining a standard temperature compensation curve P ═ P (T), and considering that the air pressure in the box is normal when the measured air pressure P in the box changes in the interval of the standard air pressure compensation area [ P (T) -X, P (T) + X ].

Overpressure time compensation:

when a train runs in a special environment such as a tunnel, the external environment changes rapidly, the air pressure in the box changes suddenly, and the condition that the monitored air pressure P exceeds the [ P (T) -X, P (T) + X ] interval occurs. Therefore, according to the statistics of the actual running condition of the train, a standard time interval delta t is set, and when the overpressure time t corresponding to the measured air pressure in the box P & gt P (T) + X or P & lt P (T) — X is less than or equal to delta t, the measured air pressure in the box is regarded as the normal state of the air pressure. As shown in fig. 2, the air pressure in the chamber measured during the time interval Δ t1 is regarded as the normal state of the air pressure; when the time range is exceeded, the monitored air pressure P has large fluctuation, and when the time range exceeds Δ t, the air pressure is considered to be over-standard, as shown in a time interval Δ t 2.

The air pressure in the box is detected as the most important index for judging whether the sealing performance of the box is invalid or not in the embodiment, the sealing state of the box is preliminarily evaluated by monitoring the change of the air pressure in the box, and three different compensation schemes such as temperature compensation, external environment compensation and overpressure time compensation are carried out according to the influence of different factors, so that the preparation for judging the air pressure of the box is ensured, and the misjudgment on the sealing performance of the box is avoided. Namely: considering that the air pressure is influenced by the temperature and the surrounding environment, fluctuation may occur, and temperature compensation and external environment influence compensation are performed. According to the rule of the influence of the temperature on the box body air pressure, a temperature compensation curve is set, the box body temperature is guaranteed to be kept in a normal working temperature change range [ T1, T2], so that the judgment error caused by overlarge temperature change in the box body is avoided, and meanwhile, the working environment of an electric component can be effectively guaranteed; further setting an external environment evaluation threshold value X according to the influence of the external environment on the box body, forming an evaluation range [ P (T) -X, P (T) + X ] by combining a temperature compensation curve, avoiding misjudgment caused by slight fluctuation of air pressure due to changes of temperature and the external environment, and ensuring the accuracy of judgment on the air pressure in the box body; meanwhile, in order to eliminate the influence of the driving environment on the air pressure in the box, a time interval delta t is set, the air pressure P in a short time has large fluctuation and is regarded as a normal condition, and the misjudgment on the sealing performance of the box body is further avoided.

(2) The sealing state of the box body is evaluated by monitoring the dust concentration in the box body:

when the box leakproofness is relatively poor, the dust enters into the box easily, condenses around the electric part, causes electric part contact failure even short circuit, detects and clears up the dust and is vital to the electric cabinet body. Therefore, in the present embodiment, the dust concentration is further used as one of the box body sealing performance judgment indexes.

And setting a box dust concentration threshold value A according to the requirement of the protection grade of the box body, and judging that the dust concentration is too high when the measured dust concentration in the box exceeds the box dust concentration threshold value A, and giving an alarm on the dust concentration in the box.

(3) Monitoring the humidity in the box to evaluate the sealing state of the box:

when the box leakproofness is relatively poor, water and vapor enter into the incasement easily, and the moisture is too big can cause the electric part to corrode, and the aqueous vapor condensation causes the electric part trouble easily, and consequently, the humidity detects also to be the important content that the incasement environment detected, further regards incasement humidity as one of box leakproofness judgement index in this embodiment. According to the requirement of the protection level of the box body, a box body humidity threshold value B is set, when the humidity in the box body exceeds the box body humidity threshold value B, the humidity is judged to be too high, and the humidity in the box body is alarmed.

(4) The air pressure in the box is set to have priority higher than that of the humidity and the dust concentration, whether the box body is sealed and failed is comprehensively judged by confirming whether the three indexes exceed standards, and therefore the alarm mode and the processing mode under various conditions are confirmed. The method specifically comprises the following steps:

when the air pressure in the box exceeds the standard, the sealing state of the box body is further judged according to the humidity and the dust concentration of the box body:

when the air pressure in the box exceeds the standard and the humidity and the dust concentration are normal, primary alarm is carried out, the detection result cannot completely judge that the box body is sealed and invalid, the fault condition is recorded, and the tightness of the box body is further detected;

when the air pressure in the box exceeds the standard and the humidity or the dust concentration exceeds the standard, performing secondary alarm, judging that the sealing performance of the box body is invalid, and performing corresponding dehumidification or dust removal treatment on the box body according to a detection result;

when the air pressure, the humidity and the dust concentration in the box exceed the standard, three-level alarm is carried out, the sealing failure of the box body is judged, and the box body is subjected to dehumidification and dust removal simultaneously.

And secondly, when the air pressure in the box is normal, whether the humidity and the dust concentration exceed the standard or not, judging that the box body is effective in sealing, not performing alarm processing, and performing corresponding dehumidification or dust removal processing on the box body according to a detection result.

In conclusion, the box sealing state monitoring and evaluating method comprehensively considers the influence of different factors on the box sealing performance, and confirms three indexes for judging the box sealing performance: and (4) comprehensively judging the sealing state of the box body by air pressure, humidity and dust concentration. The air pressure in the box is used as a main index for judging whether the box body sealing performance is invalid or not, preliminary evaluation is carried out on the box body sealing state by monitoring the change of the air pressure in the box, and three different compensation schemes such as temperature compensation, external environment compensation and overpressure time compensation are carried out according to the influence of different factors, so that the preparation for judging the air pressure in the box body is ensured, and the misjudgment on the box body sealing performance is avoided. Meanwhile, on the basis of monitoring of the air pressure in the box, the humidity and the dust concentration in the box are further increased to serve as secondary indexes, the air pressure, the humidity and the dust concentration in the box are comprehensively considered, an integral tightness judgment scheme is formed, different alarm modes are set to judge whether the sealing state of the box is invalid or not, the accuracy of judgment of the tightness of the box is guaranteed, and meanwhile, a corresponding processing mode is made according to a detection result. It should be noted that the method for monitoring and evaluating the sealing state of the box body provided by the invention is not limited to be applied to the box body of a rail train, can be applied to sealing detection of different types of box bodies, and can comprehensively judge the sealing property of the box body according to indexes such as air pressure, humidity, dust concentration and the like in the box body according to the influence of factors such as specific application environment and the like; and aiming at the air pressure in the box, corresponding temperature compensation, external environment compensation and overpressure time compensation schemes can be set according to different influence factors.

Meanwhile, the embodiment further provides a corresponding box sealing state monitoring system, a temperature sensor, a temperature adjusting device, an air pressure sensor, a humidity sensor, a dust concentration sensor and the like are arranged in the box, the temperature sensor, the temperature adjusting device, the air pressure sensor, the humidity sensor and the dust concentration sensor are all connected to the processor, the temperature sensor, the air pressure sensor, the humidity sensor and the dust concentration sensor respectively detect the temperature, the air pressure, the humidity and the dust concentration information in the box and feed back the information to the processor, the processor judges the box sealing state according to the box sealing state monitoring and evaluating method, and controls the temperature adjusting device to work when the temperature in the box is abnormal, so that the temperature in the box is adjusted and is restored to a normal temperature range.

The above description is only a preferred embodiment of the present invention, and not intended to limit the present invention in other forms, and any person skilled in the art may apply the above modifications or changes to the equivalent embodiments with equivalent changes, without departing from the technical spirit of the present invention, and any simple modification, equivalent change and change made to the above embodiments according to the technical spirit of the present invention still belong to the protection scope of the technical spirit of the present invention.