Solenoid valve operation state process monitoring system

Abstract

The invention discloses an electromagnetic valve operation state process monitoring system, and relates to the technical field of electromagnetic valve electric control systems, the system isolates and collects driving current output by a traditional electromagnetic valve driving system, on one hand, monitoring system faults caused by the abnormity of the electromagnetic valve driving system are avoided, and on the other hand, the system reliability is improved; and on the other hand, if the monitoring system is abnormal, the normal operation of the driving system is not influenced. According to the method, the short-time state of the driving current of the electromagnetic valve can be qualitatively judged, and once the driving current of the electromagnetic valve is abnormal, short-time sudden change or long-time fault can be recorded by a monitoring system and is accurate to the time point when the fault occurs, so that subsequent troubleshooting of the fault is facilitated.

Description

Technical Field

[0001] The invention relates to the technical field of solenoid valve electronic control systems, and in particular to a solenoid valve operating state process monitoring system. Background Art

[0002] The solenoid valve is an inductive element. Its valve head is usually wound with copper wire. When the power is supplied to the solenoid valve, a magnetic field is first established at the two poles of the coil of the solenoid valve head. In order to shorten the time it takes to establish the magnetic field, a larger power supply is usually applied to the solenoid valve. When the magnetic field is established, the solenoid valve is in an activated state. At this time, only a small current is needed to make the solenoid valve work normally. The solenoid valve drive current waveform is as follows: Figure 5 shown.

[0003] Figure 5 In the equation, Imax is the solenoid valve activation current value, Imin is the solenoid valve holding current value, and t 1 ~t 2 The solenoid valve activation current build-up time, t 2 ~t 3 is the solenoid valve activation time, t 3 ~t 4 is the conversion time of the solenoid valve from the activated state to the held state, t 4 ~t n0 is the solenoid valve holding time, t n1 ~t n2 is the solenoid valve closing time.

[0004] For monitoring the operation status of the solenoid valve, the existing technical solution is still a power supply and drive technical solution for a single solenoid valve. That is, the entire drive circuit is powered by a fixed output drive power supply, the controller receives the power-on command from the external host computer, the switch MOS tube is controlled by the controller to switch the on or off state, and the constant current control circuit receives the signal from the controller and conditions it to make the drive current constant at a set value. The excess voltage is limited to the drain and source of the constant current MOS tube in the constant current control circuit. The sampling monitoring circuit collects the voltage difference across the sampling resistor, converts the analog signal into a digital signal after signal conditioning, and transmits it to the controller, thereby realizing the closed-loop control of the drive current by the controller. The principle block diagram is as follows Figure 6 shown.

[0005] The main disadvantage of the above technical solution is that it focuses on providing the solenoid valve with a driving current that meets the requirements, but the recovery monitoring circuit of the power supply system itself cannot fully reflect the power supply status of the solenoid valve itself. Secondly, the power supply circuit and the recovery circuit are both contained in one circuit and processed by the same control system. Once the controller program runs away or fails, it will be impossible to know the true status of the solenoid valve and its power supply system at this time. Summary of the invention

[0006] In view of the above problems, the present invention provides a solenoid valve operating status process monitoring system for overcoming the above problems or at least partially solving the above problems.

[0007] The present invention provides the following scheme:

[0008] A solenoid valve operation status process monitoring system, comprising:

[0009] A solenoid valve driving unit, the solenoid valve driving unit is used to output a driving current to the solenoid valve;

[0010] A solenoid valve monitoring unit, the solenoid valve monitoring unit comprising a monitoring controller, a DC voltage transmitter, an operational amplifier and an analog-to-digital converter;

[0011] The DC voltage transmitter is used to isolate and transmit the voltage difference generated at both ends when the driving current flows through the solenoid valve into a linear DC analog signal; the operational amplifier is used to perform signal conditioning on the DC analog signal so that its conversion range meets the input voltage requirement of the analog-to-digital converter; the analog-to-digital converter is used to convert the received analog signal into a digital signal and upload it to the monitoring controller, so that the monitoring controller converts the digital signal into the driving current of the solenoid valve in combination with the resistance value of the solenoid valve; the monitoring controller is used to perform the following operations:

[0012] Determine a plurality of time periods included in the output state of the driving current, wherein the plurality of time periods at least include a solenoid valve activation phase, a solenoid valve holding phase, and a solenoid valve closing phase;

[0013] Determine a current determination threshold corresponding to each of the time periods;

[0014] Determine each driving current sample collection point included in each of the time periods, and sample the driving current flowing through the solenoid valve at each of the driving current sample collection points to obtain a number of sampled driving currents;

[0015] Determine whether the data state of the driving current in each time period meets the requirement according to the relationship between the current determination threshold preset in each time period and the sampled driving current in the corresponding time period;

[0016] After determining that all the sampled drive currents meet the respective specified data state requirements, determining that the operation state of the solenoid valve is normal;

[0017] After determining that the sampled driving current does not meet the specified data state requirement, it is determined that the operation state of the solenoid valve is abnormal.

[0018] Preferably: the current judgment threshold corresponding to the solenoid valve activation stage is 80% to 90% of the actual activation current value; the current judgment threshold corresponding to the solenoid valve holding stage is 80% to 90% of the actual holding current value; the current judgment threshold corresponding to the solenoid valve closing stage is the current closing threshold that can close the solenoid valve.

[0019] Preferably: the solenoid valve activation stage includes 5 driving current sample collection points; the solenoid valve holding stage includes 10 driving current sample collection points; the solenoid valve closing stage includes 5 driving current sample collection points.

[0020] Preferably: the driving current sample collection point corresponding to the first sampled driving current that satisfies the data state corresponding to the solenoid valve activation stage is determined as the starting driving current sample collection point of the solenoid valve activation stage; the time intervals of all collection points from the starting driving current sample collection point to the ending driving current sample collection point corresponding to the solenoid valve closing stage are consistent.

[0021] Preferably, the time period between the starting driving current sample collection point and the next adjacent collection point is adjusted so that the data collected at each driving current sample collection point is in a determined state.

[0022] Preferably, determining whether the data state of the driving current in each time period meets the requirement according to the relationship between the current determination threshold preset in each time period and the sampled driving current in the corresponding time period includes:

[0023] Determining that each of the sampled drive currents in the solenoid valve activation stage is greater than the current determination threshold corresponding to the solenoid valve activation stage, then determining that all of the sampled drive currents in the solenoid valve activation stage meet the data state requirement;

[0024] Determining that each of the sampled drive currents in the solenoid valve holding stage is greater than the current determination threshold corresponding to the solenoid valve holding stage, then determining that all of the sampled drive currents in the solenoid valve holding stage meet the data state requirement;

[0025] It is determined that each of the sampled drive currents in the solenoid valve closing stage is less than the current determination threshold corresponding to the solenoid valve closing stage, and then it is determined that all of the sampled drive currents in the solenoid valve closing stage meet the data state requirement.

[0026] Preferably: the driving current sample collection point where the sampled driving current that does not meet the requirements is located is obtained and reported to a superior system.

[0027] Preferably: the solenoid valve driving unit comprises a main controller, a main driving power supply, a switch MOS tube, a constant current control circuit, a constant current MOS tube, a signal conditioning circuit and a DC / DC conversion circuit; the switch MOS tube, the constant current control circuit and the signal conditioning circuit are all connected to the main controller, the DC / DC conversion circuit is respectively connected to the main driving power supply, the signal conditioning circuit and the switch MOS tube, the constant current MOS tube is respectively connected to the switch MOS tube and the constant current control circuit, and the constant current MOS tube is connected to the solenoid valve;

[0028] The main controller is used to output a driving current to the solenoid valve by controlling the signal conditioning circuit, the constant current control circuit and the switch MOS tube after receiving the solenoid valve enabling instruction issued by the upper system.

[0029] Preferably: the constant current MOS tube comprises a power type N-channel field effect MOS tube.

[0030] Preferably, the solenoid valve driving unit further comprises a sampling resistor and a recovery circuit, the sampling resistor is connected to the solenoid valve, and the recovery circuit is connected to the main controller.

[0031] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0032] The embodiment of the present application provides a solenoid valve operation status process monitoring system, which isolates and collects the drive current output by the traditional solenoid valve drive system. On the one hand, the monitoring system will not fail due to the abnormality of the solenoid valve drive system, and on the other hand, if the monitoring system is abnormal, it will not affect the normal operation of the drive system. It can make a qualitative judgment on the short-term state of the solenoid valve drive current. Once the solenoid valve drive current is abnormal, whether it is a short-term mutation or a long-term failure, it can be recorded by the monitoring system and accurately recorded to the time point of the failure, which is convenient for subsequent troubleshooting.

[0033] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1It is a schematic diagram of a solenoid valve operation status process monitoring system provided by an embodiment of the present invention;

[0036] Figure 2 It is a first schematic diagram of segmented acquisition, comparison and analysis of electromagnetic valve driving current waveform provided by an embodiment of the present invention;

[0037] Figure 3 It is a second schematic diagram of segmented acquisition, comparison and analysis of electromagnetic valve driving current waveform provided by an embodiment of the present invention;

[0038] Figure 4 is a third schematic diagram of segmented acquisition, comparison and analysis of electromagnetic valve driving current waveform provided by an embodiment of the present invention;

[0039] Figure 5 It is the solenoid valve driving current waveform;

[0040] Figure 6 It is a principle block diagram of a solenoid valve drive circuit in the prior art.

[0041] In the figure: solenoid valve drive unit 1, main controller 11, main drive power supply 12, switch MOS tube 13, constant current control circuit 14, constant current MOS tube 15, signal conditioning circuit 16, DC / DC conversion circuit 17, sampling resistor 18, recovery circuit 19, solenoid valve monitoring unit 2, monitoring controller 21, DC voltage transmitter 22, operational amplifier 23, analog-to-digital converter 24, solenoid valve 3. DETAILED DESCRIPTION

[0042] The technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all of the embodiments. Based on the embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0043] See also Figure 1 , is a solenoid valve operation status process monitoring system provided by an embodiment of the present invention, such as Figure 1 As shown, the system may include:

[0044] A solenoid valve driving unit 1, wherein the solenoid valve driving unit 1 is used to output a driving current to the solenoid valve 3;

[0045] A solenoid valve monitoring unit 2, the solenoid valve monitoring unit 2 comprising a monitoring controller 21, a DC voltage transmitter 22, an operational amplifier 23 and an analog-to-digital converter 24;

[0046] The DC voltage transmitter 22 is used to isolate and transmit the voltage difference generated at both ends when the driving current flows through the solenoid valve into a linear DC analog signal; the operational amplifier 23 is used to perform signal conditioning on the DC analog signal so that its conversion range meets the input voltage requirement of the analog-to-digital converter 24; the analog-to-digital converter 24 is used to convert the received analog signal into a digital signal and upload it to the monitoring controller 21, so that the monitoring controller 21 converts the digital signal into the driving current of the solenoid valve 3 in combination with the resistance value of the solenoid valve; the monitoring controller 21 is used to perform the following operations:

[0047] Determine a plurality of time periods included in the output state of the driving current, wherein the plurality of time periods at least include a solenoid valve activation phase, a solenoid valve holding phase, and a solenoid valve closing phase;

[0048] Determine the current judgment threshold corresponding to each of the time periods; the system provided in the embodiment of the present application uses the relationship between the set current judgment threshold and the collected real-time current to determine whether a fault occurs in the power supply system. In order to more accurately determine the current judgment threshold of each stage, in specific implementation, the embodiment of the present application can provide that the current judgment threshold corresponding to the solenoid valve activation stage is 80% to 90% of the actual activation current value; the current judgment threshold corresponding to the solenoid valve holding stage is 80% to 90% of the actual holding current value; the current judgment threshold corresponding to the solenoid valve closing stage is the current closing threshold that can close the solenoid valve.

[0049] Determine each driving current sample collection point included in each of the time periods, and sample the driving current flowing through the solenoid valve at each of the driving current sample collection points to obtain a number of sampled driving currents; since each stage needs to be maintained for a period of time when the solenoid valve is powered, the embodiment of the present application can provide that the solenoid valve activation stage includes 5 of the driving current sample collection points; the solenoid valve holding stage includes 10 of the driving current sample collection points; and the solenoid valve closing stage includes 5 of the driving current sample collection points.

[0050] In order to determine the specific time of each collection point, an embodiment of the present application can provide that the driving current sample collection point corresponding to the first sampled driving current that satisfies the data state corresponding to the solenoid valve activation stage is determined as the starting driving current sample collection point of the solenoid valve activation stage; the time intervals of all collection points from the starting driving current sample collection point to the ending driving current sample collection point corresponding to the solenoid valve closing stage are consistent.

[0051] Since in actual operation, a certain collection point may be at a position with uncertain value, the embodiment of the present application can provide for adjusting the time period between the starting drive current sample collection point and the next adjacent collection point so that the data collected by each of the drive current sample collection points are all in a certain state.

[0052] Determine whether the data state of the drive current in each time period meets the requirement according to the relationship between the current determination threshold preset in each time period and the sampled drive current in the corresponding time period; in specific implementation, the embodiment of the present application can provide that it is determined that each of the sampled drive currents in the solenoid valve activation stage is greater than the current determination threshold corresponding to the solenoid valve activation stage, and then determine that all the sampled drive currents in the solenoid valve activation stage meet the data state requirement;

[0053] Determining that each of the sampled drive currents in the solenoid valve holding stage is greater than the current determination threshold corresponding to the solenoid valve holding stage, then determining that all of the sampled drive currents in the solenoid valve holding stage meet the data state requirement;

[0054] It is determined that each of the sampled drive currents in the solenoid valve closing stage is less than the current determination threshold corresponding to the solenoid valve closing stage, and then it is determined that all of the sampled drive currents in the solenoid valve closing stage meet the data state requirement.

[0055] After determining that all the sampled drive currents meet the respective specified data state requirements, determining that the operation state of the solenoid valve is normal;

[0056] After determining that the sampled drive current does not meet the specified data state requirements, it is determined that the solenoid valve operation state is abnormal. In order to achieve a more accurate time of abnormal occurrence, the embodiment of the present application can also provide the drive current sample collection point where the sampled drive current that does not meet the requirements is obtained and reported to the upper system.

[0057] Further, the solenoid valve drive unit 1 includes a main controller 11, a main drive power supply 12, a switch MOS tube 13, a constant current control circuit 14, a constant current MOS tube 15, a signal conditioning circuit 16 and a DC / DC conversion circuit 17; the switch MOS tube 13, the constant current control circuit 14 and the signal conditioning circuit 16 are all connected to the main controller 11, the DC / DC conversion circuit 17 is respectively connected to the main drive power supply 12, the signal conditioning circuit 16 and the switch MOS tube 13, the constant current MOS tube 15 is respectively connected to the switch MOS tube 13 and the constant current control circuit 14, and the constant current MOS tube 15 is connected to the solenoid valve;

[0058] The main controller 11 is used to output a driving current to the solenoid valve by controlling the signal conditioning circuit 16 , the constant current control circuit 14 and the switch MOS tube 13 after receiving the solenoid valve enabling instruction issued by the upper system.

[0059] The constant current control circuit 14 includes a digital-to-analog converter and an operational amplifier circuit. The digital-to-analog converter is used to output a reference voltage according to the instruction issued by the main controller 11, and the operational amplifier circuit is used to condition the reference voltage to obtain the gate-source voltage required by the constant current MOS tube 15; the constant current MOS tube 15 includes a power N-channel field effect MOS tube.

[0060] The solenoid valve driving unit 1 further includes a sampling resistor 18 and a recovery circuit 19 . The sampling resistor 18 is connected to the solenoid valve, and the recovery circuit 19 is connected to the main controller 11 .

[0061] The solenoid valve operating status process monitoring system provided in the embodiment of the present application first makes the monitoring system independent of the solenoid valve power supply system, and secondly divides the output state of the driving current into multiple time periods, and samples and analyzes the driving current flowing through the solenoid valve in multiple time periods. Only when the data state of each time period meets the specified requirements can the process monitoring of the solenoid valve operating status be finally realized.

[0062] The system provided in the embodiments of the present application is described in detail below.

[0063] The present invention mainly monitors in real time whether the solenoid valve can correctly complete its specified operation. On the one hand, the solenoid valve itself may be damaged due to factors such as aging and quality problems. On the other hand, the solenoid valve power supply system may also fail due to device aging, electrical stress or extreme environmental conditions. Both of the above situations will cause the solenoid valve to be unable to complete the specified operation as required. Secondly, the solenoid valve power supply itself may cause short-term distortion of the drive current waveform due to external factors such as external interference. Although the solenoid valve is in a normal working state overall, it may actually fail to complete the specified action due to the inadequate attraction of the magnetic core.

[0064] The solenoid valve operation status process monitoring technology proposed in the present invention can monitor the operation status of the target solenoid valve during the operation of the system, and find problems before the solenoid valve and its power supply system are completely damaged and unable to work. Once the power supply current waveform of the solenoid valve is found to be abnormal within a certain period of time, it will be immediately fed back to the control system to allow the system to determine whether it is necessary to re-issue the solenoid valve power-on command to ensure that the solenoid valve completes the operation of the given task, or to manually intervene to check for potential problems. Ensure the normal operation of the solenoid valve and its power supply system.

[0065] The electromagnetic valve operation status process monitoring system provided in the present application is mainly composed of a DC voltage transmitter 22, an operational amplifier 23, an analog-to-digital converter 24, and a monitoring controller 21. The DC voltage transmitter 22 isolates and transmits the voltage difference generated at both ends when the driving current flows through the electromagnetic valve into a linear DC analog signal. The operational amplifier 23 performs signal conditioning on the DC analog signal so that its conversion range meets the input voltage requirement of the analog-to-digital converter. The analog-to-digital converter 24 converts the received analog signal into a digital signal and uploads it to the monitoring controller 21. The monitoring controller 21 analyzes and judges the data to draw conclusions about the operation status of the electromagnetic valve. The principle block diagram is shown in Figure 1.

[0066] Figure 1 The left part is the solenoid valve drive unit, which provides the normal operation of the solenoid valve. Figure 1 The driving current shown in the figure, the right part is the solenoid valve monitoring unit, which mainly determines whether the operating status of the solenoid valve is normal by monitoring the changes in the voltage difference between the two ends of the solenoid valve.

[0067] In practical applications, according to the characteristics of the solenoid valve driving current, the above collected data is analyzed and judged according to the following algorithm.

[0068] First, the voltage difference data across the electromagnetic valve 3 obtained by monitoring is converted into the magnitude of the electromagnetic valve driving current according to the resistance value of the electromagnetic valve, in order to determine the judgment threshold I of the electromagnetic valve driving current activation stage. H And the judgment threshold I of the solenoid valve drive current holding stage L And the current shutdown threshold I O , the judgment threshold I of the driving current activation stage H And the judgment threshold I of the solenoid valve drive current holding stage L The value can be defined as 80% to 90% of the actual activation current value Imax and the actual holding current value Imin, ensuring that when the drive current I exceeds I L If the solenoid valve is activated successfully and maintained for a certain period of time, the solenoid valve can be activated successfully. Similarly, when the driving current I is maintained at I L Above, the solenoid valve can work normally, and I O When the driving current I is lower than I O The solenoid valve will not be activated and no abnormal action will occur. If the above conditions are met, adjustments can be made according to actual conditions.

[0069] Secondly, the actual waveform of the solenoid valve driving current is divided into three stages: S1, S2, and S3 according to different functions. The S1 stage corresponds to the solenoid valve activation stage. In this stage, the driving current I should be ensured not to be lower than the judgment threshold I H And it lasts for a certain period of time. The S2 stage corresponds to the solenoid valve holding stage. In this stage, it should be ensured that the drive current I is not lower than the judgment threshold IL And it lasts for a certain period of time. The S3 stage corresponds to the solenoid valve closing stage. In this stage, the driving current I should be ensured to be lower than I O .

[0070] Finally, the judgment of each stage is divided according to a certain time ratio, and the collection points of each stage are obtained, such as Figure 2 As shown, the S1 stage of the solenoid valve driving current waveform is simplified to 5 driving current sample collection points from t0 to t4, the S2 stage is simplified to 10 driving current sample collection points from t5 to t14, and the S3 stage is simplified to 5 driving current sample collection points from t15 to t19.

[0071] like Figure 2 As shown, when the electromagnetic valve operation status process monitoring system detects that the first driving current value satisfies I>IH, this time point is determined as the driving current sample collection point t0. The data collection interval from t1 onwards can remain consistent, that is, t2-t1=t3-t2=...=t19-t18.

[0072] But if Figure 2 The sampling point shown at t15 is in the transition time between the S2 stage and the S3 stage. The data of the transition time cannot be determined and should be used with a value greater than I L To meet the requirements, it should be less than I O To meet the requirements, in order to make the data of the driving current sample collection point not the transition data between stages as much as possible, the time period t0~t1 is appropriately adjusted according to the actual situation to meet the above requirements, and the result is Figure 3 The diagram shown is a schematic diagram of segmented acquisition, comparison and analysis of the driving current waveform.

[0073] After adjustment, the data of each driving current sample collection point are all in a determined state. H , the values ​​in S2 stage are all greater than I L , the values ​​in S3 stage are all less than I O When the normal state of the entire solenoid valve control process is confirmed, the judgment criteria can be simplified into the following logic judgment table. The system monitors that the 20 sample collection points shown in Table 1 all meet the set judgment conditions, indicating that the solenoid valve drive task is successfully executed. The solenoid valve drive current operation state logic is shown in Table 1.

[0074] Table 1 Solenoid valve drive current operation state logic determination table

[0075]

[0076]

[0077] When the driving current is subjected to external interference and has a short-term mutation, the electromagnetic valve operation status monitoring system of the present invention can record the abnormal state, and the data of the abnormal state can be accurately recorded to the specific driving current sample collection point where it occurs. Figure 4 As shown, the driving current is disturbed by external interference in the S1 stage, so that the data collected at the driving current sample collection point t2 does not meet the judgment conditions shown in Table 1. In this case, the monitoring controller will report to the superior system that there is an abnormality in the driving action of the solenoid valve. The superior system determines whether it is necessary to re-issue the solenoid valve power-on instruction to ensure that the solenoid valve completes the operation of the given task, or to manually intervene to check for potential problems.

[0078] In summary, the solenoid valve operation status process monitoring system provided by the present application isolates and collects the drive current output by the traditional solenoid valve drive system. On the one hand, the monitoring system will not fail due to the abnormality of the solenoid valve drive system. On the other hand, if the monitoring system is abnormal, it will not affect the normal operation of the drive system. It is possible to make a qualitative judgment on the short-term state of the solenoid valve drive current. Once the solenoid valve drive current is abnormal, whether it is a short-term mutation or a long-term failure, it can be recorded by the monitoring system and accurately recorded to the time point when the failure occurred, which is convenient for subsequent troubleshooting.

[0079] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0080] It can be known from the description of the above implementation methods that those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general hardware platform. Based on such an understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product can be stored in a storage medium such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in the various embodiments of the present application or certain parts of the embodiments.

[0081] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without creative work.

[0082] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A solenoid valve operation status process monitoring system, characterized in that: include: A solenoid valve driving unit, the solenoid valve driving unit is used to output a driving current to the solenoid valve; A solenoid valve monitoring unit, the solenoid valve monitoring unit comprising a monitoring controller, a DC voltage transmitter, an operational amplifier and an analog-to-digital converter; The DC voltage transmitter is used to isolate and transmit the voltage difference generated at both ends when the driving current flows through the solenoid valve into a linear DC analog signal; the operational amplifier is used to perform signal conditioning on the DC analog signal so that its conversion range meets the input voltage requirement of the analog-to-digital converter; the analog-to-digital converter is used to convert the received analog signal into a digital signal and upload it to the monitoring controller, so that the monitoring controller converts the digital signal into the driving current of the solenoid valve in combination with the resistance value of the solenoid valve; the monitoring controller is used to perform the following operations: Determine a plurality of time periods included in the output state of the driving current, wherein the plurality of time periods at least include a solenoid valve activation phase, a solenoid valve holding phase, and a solenoid valve closing phase; Determine a current determination threshold corresponding to each of the time periods; Determine each driving current sample collection point included in each of the time periods, and sample the driving current flowing through the solenoid valve at each of the driving current sample collection points to obtain a number of sampled driving currents; Determine whether the data state of the driving current in each time period meets the requirement according to the relationship between the current determination threshold preset in each time period and the sampled driving current in the corresponding time period; After determining that all the sampled drive currents meet the respective specified data state requirements, determining that the operation state of the solenoid valve is normal; After determining that the sampled driving current does not meet the specified data state requirement, it is determined that the operation state of the solenoid valve is abnormal.

2. The solenoid valve operation status process monitoring system according to claim 1 is characterized in that: The current judgment threshold corresponding to the solenoid valve activation stage is 80% to 90% of the actual activation current value; the current judgment threshold corresponding to the solenoid valve holding stage is 80% to 90% of the actual holding current value; the current judgment threshold corresponding to the solenoid valve closing stage is the current closing threshold that can close the solenoid valve.

3. The solenoid valve operation status process monitoring system according to claim 2 is characterized in that: The solenoid valve activation stage includes 5 driving current sample collection points; the solenoid valve holding stage includes 10 driving current sample collection points; and the solenoid valve closing stage includes 5 driving current sample collection points.

4. The solenoid valve operation status process monitoring system according to claim 3 is characterized in that: Determine the driving current sample collection point corresponding to the first sampled driving current that satisfies the data state corresponding to the solenoid valve activation stage as the starting driving current sample collection point of the solenoid valve activation stage; The time intervals of all the collection points from the starting driving current sample collection point to the ending driving current sample collection point corresponding to the electromagnetic valve closing stage are consistent.

5. The solenoid valve operation status process monitoring system according to claim 4, characterized in that: The time period between the starting driving current sample collection point and the next adjacent collection point is adjusted so that the data collected at each driving current sample collection point is in a determined state.

6. The solenoid valve operation status process monitoring system according to claim 1, characterized in that: Determining whether the data state of the driving current in each time period meets the requirement according to the relationship between the current determination threshold preset in each time period and the sampled driving current in the corresponding time period includes: Determining that each of the sampled drive currents in the solenoid valve activation stage is greater than the current determination threshold corresponding to the solenoid valve activation stage, then determining that all of the sampled drive currents in the solenoid valve activation stage meet the data state requirement; Determining that each of the sampled drive currents in the solenoid valve holding stage is greater than the current determination threshold corresponding to the solenoid valve holding stage, then determining that all of the sampled drive currents in the solenoid valve holding stage meet the data state requirement; It is determined that each of the sampled drive currents in the solenoid valve closing stage is less than the current determination threshold corresponding to the solenoid valve closing stage, and then it is determined that all of the sampled drive currents in the solenoid valve closing stage meet the data state requirement.

7. The solenoid valve operation status process monitoring system according to claim 1, characterized in that: The driving current sample collection point where the sampled driving current that does not meet the requirements is located is obtained and reported to the upper system.

8. The solenoid valve operation status process monitoring system according to claim 1, characterized in that: The solenoid valve driving unit includes a main controller, a main driving power supply, a switch MOS tube, a constant current control circuit, a constant current MOS tube, a signal conditioning circuit and a DC / DC conversion circuit; the switch MOS tube, the constant current control circuit and the signal conditioning circuit are all connected to the main controller, the DC / DC conversion circuit is respectively connected to the main driving power supply, the signal conditioning circuit and the switch MOS tube, the constant current MOS tube is respectively connected to the switch MOS tube and the constant current control circuit, and the constant current MOS tube is connected to the solenoid valve; The main controller is used to output a driving current to the solenoid valve by controlling the signal conditioning circuit, the constant current control circuit and the switch MOS tube after receiving the solenoid valve enabling instruction issued by the upper system.

9. The solenoid valve operation status process monitoring system according to claim 8, characterized in that: The constant current MOS tube comprises a power type N-channel field effect MOS tube.

10. The solenoid valve operation status process monitoring system according to claim 8, characterized in that: The solenoid valve driving unit further comprises a sampling resistor and a recovery circuit, wherein the sampling resistor is connected to the solenoid valve, and the recovery circuit is connected to the main controller.

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