阅读说明：本技术 一种离心泵空转保护方法、装置、边缘网关 (Centrifugal pump idle protection method and device and edge gateway ) 是由 王朋朋 崔光亮 于 2021-07-08 设计创作，主要内容包括：本发明公开一种离心泵空转保护方法、装置、边缘网关,方法包括：S1：检测离心泵出口压力,并判断出口压力是否小于压力下限值；S2：提高离心泵的供电频率至预定供电频率,判断出口压力是否小于压力下限值；S3：判断电流是否小于电流下限值；S4：记录离心泵低电流运行时间,并判断是否长于第一时间间隔；S5：停止离心泵,记录停泵时间；S6：判断停泵时间是否长于第二时间间隔；S7：记录启停次数,判断启停次数是否大于启停次数限值；本发明的有益效果在于：通过排水压力和电流值判断离心泵的实际工作状况,准确度高；与现有技术相结合进一步提高无水状况的判断准确度采用边缘网关设备进行分析处理,避免了网络环境的影响,系统可靠性高。(The invention discloses a centrifugal pump idle running protection method, a centrifugal pump idle running protection device and an edge gateway, wherein the method comprises the following steps: s1: detecting the outlet pressure of the centrifugal pump, and judging whether the outlet pressure is smaller than a lower pressure limit value or not; s2: increasing the power supply frequency of the centrifugal pump to a preset power supply frequency, and judging whether the outlet pressure is smaller than a lower pressure limit value or not; s3: judging whether the current is smaller than a current lower limit value; s4: recording the low current running time of the centrifugal pump, and judging whether the low current running time is longer than a first time interval; s5: stopping the centrifugal pump and recording the pump stopping time; s6: judging whether the pump stopping time is longer than a second time interval or not; s7: recording the number of start-stop times, and judging whether the number of start-stop times is greater than the limit value of the number of start-stop times or not; the invention has the beneficial effects that: the actual working condition of the centrifugal pump is judged according to the drainage pressure and the current value, and the accuracy is high; the method is combined with the prior art to further improve the judgment accuracy of the waterless condition, and the edge gateway equipment is adopted for analysis and processing, so that the influence of a network environment is avoided, and the system reliability is high.)

1. A centrifugal pump idle protection method, adapted to be executed in a computing device, comprising:

s1: detecting the outlet pressure of the centrifugal pump, and judging whether the outlet pressure is smaller than a lower pressure limit value or not;

if yes, go to step S2; if not, repeating the step S1;

s2: increasing the power supply frequency of the centrifugal pump to a preset power supply frequency, re-detecting the outlet pressure of the centrifugal pump, and judging whether the outlet pressure is smaller than the lower pressure limit value or not;

if yes, go to step S3; if not, returning to the step S1;

s3: detecting the current of the centrifugal pump, and judging whether the current is smaller than the current lower limit value;

if yes, go to step S4; if not, returning to the step S1;

s4: recording the low current running time of the centrifugal pump, and judging whether the low current running time is longer than a first time interval;

if yes, go to step S5; if not, repeating the step S4;

s5: stopping the centrifugal pump and recording the pump stopping time;

s6: judging whether the pump stopping time is longer than a second time interval or not;

if yes, go to step S7; if not, repeating the step S6;

s7: recording the number of start-stop times, and judging whether the number of start-stop times is greater than the limit value of the number of start-stop times or not;

if so, stopping the centrifugal pump; if not, the centrifugal pump is restarted, and the step S1 is returned.

2. The protection method according to claim 1, characterized in that the current of the centrifugal pump is collected by a programmable logic controller connected to a frequency converter.

3. The protection method according to claim 1, wherein the step S7 further includes:

and judging the liquid level height, and stopping the centrifugal pump and sending an alarm signal to an external processing center when the liquid level height is lower than the liquid level limit value.

4. The protection method according to claim 3, characterized in that the level height is collected by means of a float valve or a level gauge.

5. The protection method according to claim 1, characterized in that said first time interval is 1 minute.

6. Protection method according to claim 1, characterized in that said second time interval is 5 minutes.

7. The protection method according to claim 1, wherein the start-stop number limit is no greater than 3.

8. An idle protection device, comprising: memory, processor and computer program stored on the memory and executable on the processor, which computer program, when executed by the processor, carries out the steps of the method according to any one of claims 1 to 7.

9. An edge gateway having centrifugal pump idle protection, comprising:

the communication interface is connected with a controller of the centrifugal pump and an outlet pressure detection device of the centrifugal pump, receives current data and an outlet pressure value of the centrifugal pump and sends an alarm signal to an external processing center;

processor, memory and a computer program stored on the memory and executable on the processor, which computer program, when executed by the processor, carries out the steps of the method according to any one of claims 1 to 7.

Technical Field

The invention relates to the technical field of water service equipment, in particular to a centrifugal pump idle running protection method, a centrifugal pump idle running protection device and an edge gateway.

Background

Along with the development of urbanization, the connection between an intelligent water supply system and the life of people is tighter and tighter, and the protection of water supply equipment is more and more important. The centrifugal pump is a key device of a water supply system, factors influencing the stable operation of the centrifugal pump are many, and the problem of water-free protection is less involved. The following problems arise when the centrifugal pump is operated without water:

1) when the centrifugal pump idles, the impeller does not contact or rarely contacts with a medium, so that the centrifugal pump cannot effectively work, and liquid cannot be normally conveyed out.

2) The idle centrifugal pump is easy to be subjected to cavitation, and damages are caused to a pump body and a flow passage part; the idle centrifugal pump is idle in a mechanical sealing mode or a packing sealing mode, and cannot be lubricated by liquid, so that dry grinding is caused, and the fast damage is caused;

3) the rotor part and the pump body of the idling centrifugal pump can generate heat, the temperature of liquid is not reduced, and narrow clearance positions (such as sealing rings) are easy to seize under the action of expansion by heat and contraction by cold;

4) the balance disc of the idle multistage centrifugal pump is not lubricated by water, and the balance disc is burnt out and damaged quickly.

Prior art mostly is being intake and is holding increasing liquid level detection device, mainly detects liquid level situation in water tank or the pond through ball-cock assembly or level gauge, with signal transmission to PLC control system, control system stops the centrifugal pump operation when the liquid level is low excessively. This means monitoring is too single, when ball-cock assembly/level gauge broke down, signal line goes wrong or hardware pipe blockage, can't detect the condition of intaking, only the motor operation detects the motor and generates heat and stops the motor operation for a period, if the number of times is more then can the greatly reduced life of centrifugal pump. The prior art therefore fails to provide effective water-free protection for centrifugal pump systems.

Disclosure of Invention

In order to solve the above problems in the prior art, a centrifugal pump idle running protection method, a centrifugal pump idle running protection device and an edge gateway are provided.

The specific technical scheme is as follows:

a centrifugal pump idle protection method, adapted to be executed in a computing device, comprising:

s1: detecting the outlet pressure of the centrifugal pump, and judging whether the outlet pressure is smaller than a lower pressure limit value or not;

if yes, go to step S2; if not, repeating the step S1;

s2: increasing the power supply frequency of the centrifugal pump to a preset power supply frequency, re-detecting the outlet pressure of the centrifugal pump, and judging whether the outlet pressure is smaller than the lower pressure limit value or not;

if yes, go to step S3; if not, returning to the step S1;

s3: detecting the current of the centrifugal pump, and judging whether the current is smaller than the current lower limit value;

if yes, go to step S4; if not, returning to the step S1;

s4: recording the low current running time of the centrifugal pump, and judging whether the low current running time is longer than a first time interval;

if yes, go to step S5; if not, repeating the step S4;

s5: stopping the centrifugal pump and recording the pump stopping time;

s6: judging whether the pump stopping time is longer than a second time interval or not;

if yes, go to step S7, otherwise repeat step S6;

s7: recording the number of start-stop times, and judging whether the number of start-stop times is greater than the limit value of the number of start-stop times or not;

if so, stopping the centrifugal pump; if not, the centrifugal pump is restarted, and the step S1 is returned.

Preferably, the current of the centrifugal pump is collected by a programmable logic controller connected with a frequency converter.

Preferably, the step S7 further includes:

and judging the liquid level height, and stopping the centrifugal pump and sending an alarm signal to an external processing center when the liquid level height is lower than the liquid level limit value.

Preferably, the liquid level is collected by a float valve or a liquid level meter.

Preferably, the first time interval is 1 minute.

Preferably, the second time interval is 5 minutes.

Preferably, the start-stop number limit is not greater than 3.

An idle protection device comprising: the centrifugal pump idle protection method comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the reading and writing processing program realizes the steps of the centrifugal pump idle protection method when being executed by the processor.

An edge gateway having centrifugal pump idle protection, comprising:

the communication interface is connected with a controller of the centrifugal pump and an outlet pressure detection device of the centrifugal pump, receives current data and an outlet pressure value of the centrifugal pump, and sends an alarm signal to an external processing center;

a processor, a memory and a computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the centrifugal pump idle protection method described above.

The technical scheme has the following advantages or beneficial effects:

1. the pressure detection device and the current detection device are arranged to effectively judge the actual working condition of the centrifugal pump according to the drainage pressure and the current value, so that the accuracy is high;

2. the method can be combined with the prior art to further improve the judgment accuracy of the anhydrous condition;

3. the edge gateway equipment is adopted to analyze and process the acquired data, so that the influence of the network environment on equipment monitoring is avoided;

4. the data acquisition and transmission are completed through the programmable logic controller, equipment does not need to be added, the system reliability is improved, and the cost is reduced.

Drawings

Embodiments of the present invention will now be described more fully hereinafter with reference to the accompanying drawings. The drawings are, however, to be regarded as illustrative and explanatory only and are not restrictive of the scope of the invention.

FIG. 1 is a flow chart of an embodiment of the present invention;

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The invention is further described with reference to the following drawings and specific examples, which are not intended to be limiting.

The invention comprises

A centrifugal pump idle protection method, suitable for execution in a computing device, as shown in fig. 1, comprising:

s1: detecting the outlet pressure of the centrifugal pump, and judging whether the outlet pressure is smaller than a lower pressure limit value or not;

if yes, go to step S2; if not, repeating the step S1;

specifically, the pressure detection device is arranged at the outlet of the centrifugal pump, so that the drainage pressure of the centrifugal pump can be effectively detected, and when the drainage pressure is too small, the centrifugal pump is possibly in an idling state. In general, the lower pressure limit is set to the discharge pressure value when the centrifugal pump operates at the lowest power, and when the reading of the pressure detection device is lower than the discharge pressure value when the centrifugal pump operates at the lowest power, the discharge pressure value can be considered to be obviously too low, so as to improve the accuracy of judgment.

S2: increasing the power supply frequency of the centrifugal pump to a preset power supply frequency, re-detecting the outlet pressure of the centrifugal pump, and judging whether the outlet pressure is smaller than a lower pressure limit value or not;

if yes, go to step S3; if not, go back to step S1;

s3: detecting the current of the centrifugal pump, and judging whether the current is smaller than the current lower limit value;

if yes, go to step S4; if not, go back to step S1;

specifically, when the centrifugal pump is operated, the current value increases as the load increases, and when the current value is significantly too low, the centrifugal pump can be considered to be in a no-load idling state. In general, the lower current limit value is set to be a current value from the start of the frequency converter to the start of the operation of the centrifugal pump, and if the measured current value is smaller than the current value from the start of the frequency converter to the start of the operation of the centrifugal pump, it can be considered that the current value of the centrifugal pump is obviously too low, and the centrifugal pump is in a no-load idling state.

Furthermore, by increasing the frequency of the frequency converter to a preset power supply frequency, misjudgment caused by low power of the centrifugal pump can be avoided, and the judgment accuracy is improved.

S4: recording the low-current running time of the centrifugal pump, and judging whether the low-current running time is longer than a first time interval;

if yes, go to step S5; if not, repeating the step S4;

specifically, the centrifugal pump may appear because the converter just starts the low current situation or the transient anhydrous idle running process that leads to in the course of the work, can get rid of because this kind of situation leads to the low current operation of centrifugal pump through setting up first time interval, reduces the false alarm rate.

S5: stopping the centrifugal pump and recording the pump stopping time;

s6: judging whether the pump stopping time is longer than a second time interval or not;

if yes, go to step S7; if not, repeating the step S6;

specifically, after the centrifugal pump is stopped, the centrifugal pump may be damaged if the centrifugal pump is started quickly, and therefore, after the centrifugal pump is stopped, the centrifugal pump needs to be restarted after waiting for a period of time.

S7: recording the number of start-stop times, and judging whether the number of start-stop times is greater than the limit value of the number of start-stop times or not;

if so, stopping the centrifugal pump; if not, the centrifugal pump is restarted and the process returns to the step S1.

Specifically, the centrifugal pump can be started and stopped for multiple times, so that corresponding faults can be eliminated by starting and stopping the centrifugal pump, when the centrifugal pump is still in an anhydrous idling state after the centrifugal pump is started and stopped for multiple times, the centrifugal pump can be continuously started and stopped, adverse effects can be possibly caused on the whole system, and the centrifugal pump needs to be closed and operation and maintenance personnel are informed to handle the corresponding faults.

In a preferred embodiment, the current of the centrifugal pump is collected by a programmable logic controller connected to a frequency converter.

Specifically, the programmable logic controller can be connected with a frequency converter to directly acquire the current value input into the centrifugal pump, and the acquisition accuracy and the reliability are high.

In a preferred embodiment, step S7 further includes:

and judging the liquid level height, and stopping the centrifugal pump and generating an alarm signal to a processing center when the liquid level height is lower than the liquid level limit value.

In a preferred embodiment, the liquid level is collected by a float valve or a level gauge.

Specifically, this technical scheme can with prior art, through set up the method that ball-cock assembly and level gauge detected centrifugal pump intake water level and combine to use in pond or water storage cabin, effectively improve the judgement degree of accuracy to the water level state.

In a preferred embodiment, the first time interval is 1 minute.

Specifically, according to experimental results, the influence of the idling time of the centrifugal pump within 1 minute on the centrifugal pump is small, so that the limit value of the low-current running time is set to about 1 minute, the judgment accuracy is improved, and meanwhile damage to the centrifugal pump is avoided.

In a preferred embodiment, the second time interval is 5 minutes.

Specifically, according to experimental results, the centrifugal pump is frequently started after being stopped to cause faults, such as overheating of a motor and the like, and the influence of frequent starting and stopping on the centrifugal pump can be avoided by setting the stop interval of about 5 minutes.

In a preferred embodiment, the number of start stops limit is no greater than 3.

Specifically, when the centrifugal pump is restarted for 3 times, a fault still exists, which indicates that the centrifugal pump is in a water-free state and cannot recover water supply by adjusting a water supply system, and operation and maintenance personnel need to be contacted to handle the fault.

An idle protection device comprising: the centrifugal pump idle protection method comprises a memory, a processor and a computer program which is stored on the memory and can run on the processor, wherein the steps of the centrifugal pump idle protection method are realized when the read-write processing program is executed by the processor.

An edge gateway having centrifugal pump idle protection, comprising:

the communication interface is connected with the controller of the centrifugal pump and the outlet pressure detection device of the centrifugal pump, receives current data and outlet pressure value of the centrifugal pump and sends an alarm signal to an external processing center;

a processor, a memory and a computer program stored on the memory and executable on the processor, the computer program, when executed by the processor, implementing the steps of the centrifugal pump idle protection method described above.

The technical scheme has the following advantages or beneficial effects:

1. the pressure detection device and the current detection device are arranged to effectively judge the actual working condition of the centrifugal pump according to the drainage pressure and the current value, so that the accuracy is high;

2. the method can be combined with the prior art to further improve the judgment accuracy of the anhydrous condition;

3. the edge gateway equipment is adopted to analyze and process the acquired data, so that the influence of the network environment on equipment monitoring is avoided;

4. the data acquisition and transmission are completed through the programmable logic controller, equipment does not need to be added, the system reliability is improved, and the cost is reduced.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.