CN115306692B

CN115306692B - Method and control device for alarming temperature of compressor

Info

Publication number: CN115306692B
Application number: CN202210832886.0A
Authority: CN
Inventors: 庞颢; 陈震; 李振强
Original assignee: Shenzhen Threshold Industrial Technology Co ltd
Current assignee: Shenzhen Haige Jingu Industrial Technology Co.,Ltd.
Priority date: 2022-07-14
Filing date: 2022-07-14
Publication date: 2023-06-20
Anticipated expiration: 2042-07-14
Also published as: CN115306692A

Abstract

The application provides a method and a control device for alarming temperature of a compressor. The method is applied to a controller of a compressor control system, and the method includes repeatedly performing the following operations in a predetermined scanning period: acquiring and storing a current value of the site temperature of the compressor; calculating a temperature change rate according to the current value of the site temperature and the last value of the site temperature and the preset scanning period; when the temperature change rate is larger than the change rate threshold, outputting a temperature abnormality signal, and keeping outputting until a reset signal is received; and sending out a temperature abnormality alarm according to the temperature abnormality signal. According to the technical scheme, the authenticity of the temperature detection value is judged according to the change rate threshold, the detected abnormal temperature signal is shielded and stopped, and error stopping is prevented.

Description

Method and control device for alarming temperature of compressor

Technical Field

The application relates to the technical field of industrial control, in particular to a method and a control device for alarming the temperature of a compressor.

Background

The compressor is an important device in devices such as space division, chemical production and the like. The large compressor set plays a role in production, and once the large compressor set fails, the normal operation of production is seriously affected. In order to ensure safe operation, the vibration and temperature parameters are generally detected for protection.

However, since there are many on-site electrical devices, the production environment is complex, and the automatic detection is basically a weak electrical signal, electromagnetic interference is very easy to occur in the signal transmission process, and particularly, the thermal resistance temperature signal is easy to be disturbed. If a temperature measurement signal from the site is mixed into an interference signal during transmission, the computer detection system is difficult to distinguish, so that once the temperature signal is detected to be suddenly changed to a shutdown value, an interlocking shutdown is caused.

In addition, when the thermal resistance thermometer is operated in a place where vibration is serious for a long period of time, disconnection, short circuit or poor contact are liable to occur, and abnormal abrupt change of the temperature value is liable to occur. In temperature protection, the jump of the measured value often causes protection malfunction, resulting in shutdown, which causes great loss to production.

In the temperature false signal filtering processing, the normal temperature change of the thermometer can be judged in a smooth filtering algorithm mode and the like, so that abnormal temperature interference signals are shielded while the normal operation of the temperature protection logic of the compressor is ensured. However, this approach takes up much computing resources, is inefficient, and may result in false negatives.

The above information disclosed in the background section is only for enhancement of understanding of the background of the application and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.

Disclosure of Invention

The application aims to provide a method and a control device for alarming the temperature of a compressor, which can prevent false interlocking stop caused by temperature abnormal signals.

The user characteristics and advantages of the present application will become apparent from the detailed description set forth below, or may be learned in part by practice of the application.

According to an aspect of the present application, there is provided a method for compressor temperature warning, applied to a controller of a compressor control system, the method comprising repeatedly performing the following operations in a predetermined scan cycle:

acquiring and storing a current value of the site temperature of the compressor;

calculating a temperature change rate according to the current value of the site temperature and the last value of the site temperature and the preset scanning period;

when the temperature change rate is larger than the change rate threshold, outputting a temperature abnormality signal, and keeping outputting until a reset signal is received;

and sending out a temperature abnormality alarm according to the temperature abnormality signal.

According to another aspect of the present application, there is provided a control apparatus including:

a processor;

a memory having a computer program stored thereon;

the aforementioned method is implemented when the processor executes the computer program.

According to an example embodiment, by judging the authenticity of the temperature detection value according to the change rate threshold value, the detected abnormal temperature signal is shielded from shutdown, and false interlocking shutdown caused by the temperature abnormal signal is prevented. According to other embodiments, a cyclic alarm may be provided to alert an operator to the process based on the temperature anomaly signal.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The above and other objects, features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

Fig. 1 shows a schematic diagram of a control system for an air separation plant.

FIG. 2 illustrates a rate of change of temperature when simulating a harsh operating environment according to an example embodiment.

FIG. 3 illustrates a flow chart of a method for compressor temperature warning according to an example embodiment.

FIG. 4 illustrates a method flow diagram for periodic alerting when a temperature anomaly signal is not eliminated, according to an example embodiment.

FIG. 5 illustrates a system block diagram for compressor temperature alerting implemented in accordance with an example embodiment.

Fig. 6 shows a block diagram of a control device according to an example embodiment of the present application.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar parts, and thus a repetitive description thereof will be omitted.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the present application. One skilled in the relevant art will recognize, however, that the aspects of the application can be practiced without one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the application.

The flow diagrams depicted in the figures are exemplary only, and do not necessarily include all of the elements and operations/steps, nor must they be performed in the order described. For example, some operations/steps may be decomposed, and some operations/steps may be combined or partially combined, so that the order of actual execution may be changed according to actual situations.

The terms first, second and the like in the description and in the claims of the present application and in the above-described figures, are used for distinguishing between different objects and not for describing a particular sequential order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those skilled in the art will appreciate that the embodiments described herein may be combined with other embodiments.

Fig. 1 shows a schematic diagram of a control system 100 for an air separation plant, which may be based on DCS or PLC.

As shown in FIG. 1, the control system 100 may include an electrical unit 102, a motor 104, a compressor 106, a controller 108, a field stop button 110, solenoid and self-regulating valve units 112, a human-machine interface (HMI: human machine interface) 114, and the like.

The electrical unit 102 is used to control the compressor 106, the power circuit components of the motor 104, which may include conventional controls such as vacuum circuit breakers to control the main circuit of the compressor, devices for buck starting, secondary protection circuits, etc., and will not be described in detail herein.

The controller 108 may issue control instructions based on the information collected, such that the electrical unit 102 controls the start and stop of the compressor 106 based on the instructions issued by the controller 108.

The controller 108 may be a DCS and/or PLC controller for periodically executing system monitoring logic. For example, the controller 108 may monitor status signals of the on-site shutdown button 110, operating status signals of the compressor 106, and related compressor process parameters.

If the controller 108 collects a true value signal (true) from the status signal of the on-site shutdown button 110, a shutdown alarm is output in which the on-site shutdown button is pressed.

If the controller 108 collects the operating state signal of the compressor 106 as a false value signal (false), a loss of compressor operating signal alarm is issued.

The controller 108 uses the compressor protection logic to determine whether a shutdown alarm condition is met based on the compressor process parameters. The compressor process parameters may include compressor temperature parameters, such as temperature signals collected by a platinum-hot resistance thermometer and transmitted to the controller 108. When the compressor temperature exceeds the shutdown threshold, the compressor protection logic outputs a true signal (true), i.e., a temperature shutdown alarm condition is determined to be met, the controller 108 outputs a stop compressor signal to the electrical unit 102 and a compressor interlock shutdown alarm is sent. The compressor protection logic may employ existing or well-known compressor protection function blocks or methods, and are not described in detail herein.

The controller 108 may record the alarm so that a worker may locate and confirm the source of the fault by analyzing the alarm record.

The human-machine interface 114 is operable to load and unload the compressor, and the controller 108 processes the compressor accordingly and outputs signals to the solenoid valve and the automatic control valve unit 112 via the signal output module 1024, thereby automatically adjusting the valve to load and unload the compressor.

During temperature signal processing, false signals generated by factors such as interference and the like need to be judged and processed. In the general filtering process, the normal temperature change of the thermometer can be judged by a smooth filtering algorithm and the like, so that abnormal temperature interference signals are shielded while the normal operation of the temperature protection logic of the compressor is ensured. However, this approach handles the situation where memory and computing resources are occupied, and there are inefficiencies that may not be real-time. Furthermore, this approach may also lead to missed reports and may therefore lead to serious consequences.

Therefore, the method for judging whether the temperature jump is normal according to the temperature change rate threshold value is provided, so that the normal temperature protection is prevented from being shielded by errors caused by erroneous judgment, and larger accidents are avoided.

The technical scheme and advantages of the present application will be described in detail with reference to examples.

According to an example embodiment, the test harsh conditions were simulated by moving a platinum-resistance thermometer from an environment of-193 ℃ to an extreme environment of 100 ℃. In actual production, the compressor does not have such a severe working condition environment. The following describes an example embodiment using a DCS control system as an example, it being readily understood that this embodiment may also be applied to a PLC control system.

For this purpose, a platinum thermal resistance thermometer is connected to a thermal resistance measurement module of a DCS control system through a cable, and data obtained by scanning by the DCS controller is stored in a DCS historical database. The actual temperature values are displayed on the DCS screen, refreshed every second, and trends are recorded in the DCS trend configuration. Firstly, a platinum thermal resistance thermometer is placed into liquid nitrogen at the temperature of-193 ℃, and after DCS pictures show the temperature of-193 ℃, the thermal resistance is rapidly placed into boiled water at the temperature of 100 ℃. The temperature change was recorded by a scan period of 1 second by the DCS controller. The maximum rate of change per second is not more than 40 ℃/sec as can be seen from the temperature rise graph. Through multiple experiments, the maximum value of the temperature change rate can be determined to be in the range of 30-40 ℃/s under the possible severe working conditions.

It can be seen that in the compressor temperature protection logic, the normal temperature change rate threshold of the platinum resistance thermometer is set within the range of 30-40 ℃/sec, so that the normal temperature change can be prevented from being filtered out, and the abnormal temperature value can be filtered out.

The method of fig. 3 may be performed by a controller cycle scan of the compressor control system of fig. 1, which may be 500 milliseconds or 1 second, or other suitable values depending on the application.

Referring to fig. 3, at S301, a current value of a field temperature of a compressor is acquired and stored.

The controller may periodically execute system monitoring logic. For example, the DCS control system thermal resistance measurement module periodically detects the compressor field temperature signal via a field platinum thermal resistance thermometer.

In S303, a temperature change rate is calculated from the current value of the field temperature, the last value of the field temperature, and a predetermined scan period.

And dividing the difference between the current value and the last value of the field temperature by the scanning period to obtain the temperature change rate. If the scanning period is 1 second, the difference between the current value and the last value can be directly taken as the temperature change rate.

At S305, when the temperature change rate is greater than the change rate threshold, a temperature abnormality signal is output, and the output is maintained until a reset signal is received.

According to some embodiments, the rate of change threshold is obtained experimentally beforehand, as previously described, and may be in the range of 30-40 ℃/sec.

When the calculated temperature change rate based on the acquired data is greater than a change rate threshold, for example, greater than 40 ℃/sec, a temperature anomaly signal, for example, a false signal (false) may be output. In addition, the temperature anomaly signal may remain output until a reset signal is received. According to some embodiments, an operator is required to handle the anomaly, and the output temperature anomaly signal is reset after the manual reset signal is generated.

In S307, a temperature abnormality alarm is issued according to the temperature abnormality signal.

According to an exemplary embodiment, if a temperature anomaly signal is obtained, a temperature anomaly alarm, such as sounding and generating a pop-up alarm, is issued.

According to some embodiments, when the temperature anomaly signal is not eliminated, a periodic alarm may also be provided to periodically alert an operator to process the anomaly and cause the system to eliminate the temperature anomaly signal by a manual reset signal. For example, when the alarm is triggered, the operator always alarms without silencing and confirming. Periodic alarms herein refer to an operator pressing an alarm acknowledge (e.g., direct silencing) where the alarm sound is no longer loud, but the alarm is re-triggered after a period of time, while the DCS itself is not.

According to some embodiments, when the rate of change of temperature is less than the rate of change threshold, a temperature normal signal is output, and a current value of the in-situ temperature may be output for making a compressor shutdown protection determination based on the temperature normal signal. The compressor shutdown protection judging module can perform temperature protection shutdown judgment according to the current value of the field temperature so as to determine whether to output a shutdown signal according to the field compressor temperature.

According to some embodiments, when a temperature anomaly signal is present, a set temperature value may be output according to the temperature anomaly signal. The set temperature value may be a preset value that is less than a shutdown temperature threshold, such that the compressor shutdown protection module may execute normal decision logic and may not generate a shutdown signal.

Thus, according to the example embodiment, the controller can distinguish the correct temperature signal while designing the logic of the shielding temperature false signal, so that the situation that the normal temperature protection is shielded by mistake due to misjudgment and larger accidents are caused is prevented. The worst rate of change simulated by the platinum resistance thermometer in the actual running environment is used as a rate of change threshold, so that interference signals can be reliably eliminated, and the reliability and safety of the system are improved.

Referring to fig. 4, in S401, an output signal is periodically generated based on a temperature anomaly signal and a feedback signal, which is obtained by performing a turn-off delay operation on the output signal.

For example, the temperature anomaly signal may be used as an S-terminal input signal of the RS flip-flop, and the Q-terminal output signal of the RS flip-flop may be subjected to an off-delay operation as an R-terminal input signal, so that when the temperature anomaly signal is continuously present, a periodic output signal is generated at the Q-terminal of the RS flip-flop.

In S403, a timing pulse is generated from the output signal. According to some embodiments, a timing pulse of a predetermined duration may be generated from the output signal to trigger an alarm. For example, the predetermined time period may be 1 second.

At S405, an alarm is generated based on the timing pulse. According to some embodiments, the alarm may be generated based on a timed pulse, including a pop-up alarm and/or an audible alarm generated through a human-machine interface.

The method shown in fig. 4 can be realized by configuration software in a feedback mode, has strong adaptability, and is easy to use and popularize.

FIG. 5 illustrates a system block diagram for compressor temperature alerting implemented in accordance with an example embodiment. The system shown in fig. 5 can be implemented by DCS or PLC configuration software and is triggered to execute by periodic scanning by a controller.

Referring to fig. 5, a temperature signal may be acquired using a periodic scan characteristic of a DCS controller or a PLC controller to detect a step response of temperature. In the DCS/PLC, variables are established for the temperature points to be interlocked and protected, and the last scanned measurement value of each temperature point is assigned to the corresponding variable, and the scanning period may be, for example, 1 second.

The current value of the site temperature of the compressor and the last value of the site temperature are input into a subtraction module SUB, and the difference between the current value and the last value is taken as an absolute value by an absolute value module ABS because the scanning period is 1 second, so that the temperature change rate can be obtained.

The temperature change rate is input to the comparison module GE while the comparison module GE also inputs a predetermined change rate threshold, such as 40 ℃/sec. If the temperature change rate is greater than or equal to 40 ℃/sec, the comparison module GE outputs a temperature anomaly signal (true signal true), otherwise, false is output.

The comparison module GE is connected with the S end of the RS trigger RS. Therefore, when the GE outputs true, the S end is true, so that the Q end of the RS trigger outputs true.

The characteristic of the RS trigger is that the S end triggers once, and as long as the RESET signal RESET of the R end is not true, the Q end of the trigger outputs true. Even if the S terminal is changed into false again, the Q terminal of the RS trigger still outputs true; when the trigger R terminal is true (trigger reset), the Q terminal becomes false.

When the temperature is suddenly changed, the RS trigger outputs true, and an alarm signal can be output through a human-computer interface, for example, flicker alarm information is displayed on the interface.

According to an exemplary embodiment, the temperature anomaly signal (true signal true) may be output to the S end of the second RS flip-flop RS2, and then the Q end outputs true to the pulse timer TP, and the pulse timer TP may output a pulse of, for example, 1 second to the human-computer interface, so that a small window alarm may be popped up through the human-computer interface to remind an operator to perform the fault detection process on the thermometer.

The output of the Q end is also fed back to the R end of the second RS trigger RS2 through the turn-off delay module OFFDELAY. Turning off the delay module OFFDELAY may produce a delay of, for example, 180 seconds. The function of the shutdown delay module OFFDELAY is as follows: when the input is changed from false to true, immediately outputting true; and when the input is changed from true to false, the true is continued to be output, and the timer is started, and when the time is accumulated to a set time (for example, 180S is set here), false is output.

The second RS flip-flop RS2 outputs true to the off delay module OFFDELAY, which immediately outputs true to the R terminal of the second RS flip-flop RS 2. At this time, the R terminal is true, and the S terminal is true at this time, but the RS flip-flop is the R terminal priority function block, so the second RS flip-flop RS2 is reset, and outputs false to the input terminal of the off delay module OFFDELAY. The off delay module OFFDELAY starts timing while continuing to output true, and when the timing time reaches a set time, for example 180S, the off delay module OFFDELAY outputs false. At this time, the S terminal of the second RS flip-flop RS2 is input by the previous stage RS flip-flop. The R end of the upper-stage trigger is connected with a reset button, and a technician confirms to press down to reset after troubleshooting. As long as the fault is not being troubleshooted, the pressing of this button is not acknowledged, the output of the upper level RS flip-flop is always true, and true is still output even after the fault or disturbance disappears. When the time delay module OFFDELAY is turned off and the false is output, the R end of the second RS trigger RS2 is false, and since the S end is still true, the second RS trigger RS2 outputs true again, triggers the pulse timer TP again, and outputs a pulse of 1 second to the man-machine interface again, so that a small window alarm is popped up again through the man-machine interface to remind an operator to perform fault detection processing on the thermometer. Meanwhile, the off delay module OFFDELAY outputs true, and resets the connected second RS trigger RS 2. And the method is circulated again, the popup window alarm is continuously sent out at intervals until the reset button is pressed down after the thermometer fault is eliminated, the upper-stage RS trigger is reset, and the circulation popup window alarm is ended.

According to some embodiments, the RS flip-flop Q terminal is connected to the first input terminal IN1 of the selection module SEL. The function of the selection module SEL is: when the first input terminal IN1 is true, selecting and outputting the input of the third input terminal IN 3; when the first input terminal IN1 is false, the input of the second input terminal IN2 is selected and outputted.

When the current value of the field temperature is normal, the RS flip-flop outputs false, and the first input terminal IN1 of the selection module SEL outputs IN2 if the input is false.

According to some embodiments, the temperature value may be displayed at the control interface according to an output of the selection module SEL.

According to some embodiments, an output of the selection module SEL may be connected to one input of the second comparison module GE2, with the other input of the second comparison module GE2 inputting the shutdown temperature threshold. When the temperature has no abrupt change (the temperature change rate is smaller than the change rate threshold), but the temperature slowly rises due to equipment reasons, the selection module SEL outputs a current value of the field temperature, and if the temperature is greater than or equal to a set shutdown temperature threshold, the second comparison module GE2 outputs a temperature protection true value signal (true) to the compressor temperature interlock protection module to shutdown the compressor. And when there is a temperature abrupt change (the temperature change rate is greater than the change rate threshold), the selection module SEL outputs a temperature set value less than the shutdown temperature threshold, and the second comparison module GE2 outputs a temperature protection false value signal (false), so that the compressor temperature interlock protection module does not generate an action to stop the compressor.

According to an example embodiment, there may be two alarms when the temperature is suddenly changed. First, pop up the abnormal alarm of temperature in the alarm column of man-machine interface, and can accompany the audible alarm, for example can display the flashing typeface on the picture. Meanwhile, a secondary small window alarm can be popped up to remind operators. At this time, even if the operator eliminates the alarm sound and closes the pop-up secondary widget alarm, since this temperature is extremely important, if the actual troubleshooting process is not performed and reset, the widget is popped up again after a predetermined time (for example, 180 seconds) to remind the operator of timely processing.

As shown in fig. 6, the control device 30 includes a processor 12 and a memory 14. The control device 30 may also include a bus 22, a network interface 16, and an I/O interface 18. The processor 12, memory 14, network interface 16, and I/O interface 18 may communicate with each other via a bus 22.

The processor 12 may include one or more general purpose CPUs (Central Processing Unit, central processing units), microprocessors, or application specific integrated circuits, etc. for executing associated program instructions.

Memory 14 may include machine-system-readable media in the form of volatile memory, such as Random Access Memory (RAM), read Only Memory (ROM), and/or cache memory. Memory 14 is used to store one or more programs including instructions as well as data. The processor 12 may read instructions stored in the memory 14 to perform the methods described above in accordance with embodiments of the present application.

The control device 30 may also communicate with one or more networks via the network interface 16. The network interface 16 may be a wired network interface or a wireless network interface, or may be a virtual network interface.

The control device 30 may also communicate with one or more external devices (e.g., audio input devices, audio output devices, cameras, keyboards, mice, displays, various types of sensors, etc.) through an input/output (I/O) interface 18.

Bus 22 may include an address bus, a data bus, a control bus, and the like. Bus 22 provides a path for exchanging information between the components.

It should be noted that, in the implementation process, the control device 30 may further include other components necessary for achieving the normal operation. Furthermore, it will be understood by those skilled in the art that the above-described apparatus may include only the components necessary to implement the embodiments of the present description, and not all the components shown in the drawings.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.

In the several embodiments provided in this application, it should be understood that the disclosed apparatus may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, such as a division of units, merely a division of logic functions, and there may be additional divisions in actual implementation, such as multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be through some service interface, device or unit indirect coupling or communication connection, electrical or otherwise.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable memory. Based on such understanding, the technical solution of the present application may be embodied in essence or a part contributing to the prior art or all or part of the technical solution in the form of a software product stored in a memory, including several instructions for causing a computer device (which may be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the methods of the embodiments of the present application.

The embodiments of the present application have been described and illustrated in detail above. It should be clearly understood that this application describes how to make and use particular examples, but is not limited to any details of these examples. Rather, these principles can be applied to many other embodiments based on the teachings of the present disclosure.

Those skilled in the art will readily appreciate from the disclosure of the exemplary embodiments that the present disclosure may be adapted to provide at least one or more of the following advantages.

According to an example embodiment, by judging the authenticity of the temperature detection value according to the change rate threshold value, the detected abnormal temperature signal is shielded from shutdown, preventing false shutdown.

According to some embodiments, a cyclic alarm can be given according to the temperature anomaly signal to remind an operator of the treatment.

According to some embodiments, by adopting the worst temperature change rate simulated in the actual running environment as a change rate threshold, interference signals can be reliably eliminated, and the reliability and safety of the system can be improved.

According to some embodiments, the logic of the shielding temperature false signal is designed, and meanwhile, the controller can distinguish the correct temperature signal, so that the situation that the normal temperature protection is shielded by mistake due to misjudgment and larger accidents are caused is prevented.

The foregoing may be better understood in light of the following clauses:

1. a method for compressor temperature warning, for use in a controller of a compressor control system, the method comprising repeatedly performing the following operations in a predetermined scan cycle:

2. The method of clause 1, wherein the predetermined scan period is 1 second or 500 milliseconds.

3. The method of clause 1, wherein the rate of change threshold is in the range of 30-40 ℃/sec.

4. The method of clause 1, wherein the rate of change threshold is obtained in advance by experiment.

5. The method of clause 1, further comprising:

outputting a temperature normal signal when the temperature change rate is smaller than a change rate threshold value;

and outputting the current value of the site temperature according to the temperature normal signal for judging the shutdown protection of the compressor.

6. The method of clause 1, wherein the reset signal comprises a manual reset signal.

7. The method of clause 1, further comprising: and periodically alarming when the temperature abnormality signal is not eliminated.

8. The method of clause 7, wherein periodically alerting when the temperature anomaly signal is not eliminated, comprises:

periodically generating an output signal based on the temperature abnormal signal and a feedback signal, wherein the feedback signal is obtained by performing turn-off delay operation on the output signal;

generating a timing pulse based on the output signal;

and generating an alarm according to the timing pulse.

9. The method of clause 8, wherein generating an alarm based on the timing pulse, comprises:

a pop-up window alarm and/or an audible alarm is generated through a human-machine interface.

10. The method of clause 1, further comprising: and outputting a set temperature value according to the temperature abnormality signal, wherein the set temperature value is a preset value smaller than a shutdown temperature threshold.

11. The method of clause 10, wherein the set temperature value is in the range of 20-35 ℃.

12. A control apparatus, comprising:

a processor;

a memory having a computer program stored thereon;

the method of any one of clauses 1-11 being implemented when the processor executes the computer program.

Exemplary embodiments of the present application are specifically illustrated and described above. It is to be understood that this application is not limited to the details of construction, arrangement or method of implementation described herein; on the contrary, the intention is to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Claims

1. A method for compressor temperature warning, applied to a controller of a compressor control system, comprising repeatedly performing the following operations in a predetermined scan cycle:

when the temperature change rate is greater than or equal to a change rate threshold, outputting a temperature abnormality signal, and maintaining output until a reset signal is received, including:

inputting the temperature change rate and the change rate threshold value into a comparison module, and outputting a true value signal by the comparison module if the temperature change rate is greater than or equal to the change rate threshold value;

the comparison module is connected to the S end of the first RS trigger, when the comparison module outputs a true value signal, the Q end of the first RS trigger outputs the true value signal,

wherein the first RS flip-flop R terminal receives the reset signal;

sending out a temperature abnormality alarm according to the temperature abnormality signal;

and when the temperature abnormality signal is not eliminated, periodically alarming, including:

outputting a true value signal output by the Q end of the first RS trigger to the S end of the second RS trigger, and outputting the Q end of the second RS trigger to a pulse timer, wherein the pulse timer outputs a timing pulse to a man-machine interface so as to generate an alarm according to the timing pulse;

meanwhile, the output of the Q end of the second RS trigger is fed back to the R end of the second RS trigger through the turn-off delay module, so that the second RS trigger outputs signals at intervals according to the time set by the turn-off delay module to remind operators;

wherein the change rate threshold is in the range of 30-40 ℃/s, and the change rate threshold is obtained in advance through the following experiment:

the platinum resistance thermometer was moved from the environment of-193 ℃ to the extreme environment of 100 ℃ to simulate testing for severe conditions.

2. The method of claim 1, wherein the predetermined scan period is 1 second or 500 milliseconds.

3. The method as recited in claim 1, further comprising:

4. The method of claim 1, wherein the reset signal comprises a manual reset signal.

5. The method of claim 1, wherein generating an alarm based on the timing pulse comprises:

and generating a popup alarm and/or an audible alarm through the man-machine interface.

6. The method as recited in claim 1, further comprising: and outputting a set temperature value according to the temperature abnormality signal, wherein the set temperature value is a preset value smaller than a shutdown temperature threshold.

7. The method of claim 6, wherein the set temperature value is in the range of 20-35 ℃.

8. A control apparatus, characterized by comprising:

a processor;

a memory having a computer program stored thereon;

the method of any of claims 1-7 being implemented when the processor executes the computer program.