JP2020007920A - Device and method for detecting abnormality of liquid pump - Google Patents

Abstract

To simplify a constitution required for detecting abnormality of a liquid pump.SOLUTION: An abnormality detection device comprises a reference setting value storage part 5 for pre-storing a reference flow rate setting value of a flow rate feedback control to control a valve 3, so that a flow rate measurement value of liquid emitted from a liquid pump 1 is equal to a flow rate setting value, a setting state detection part 6 for determining whether the flow rate measurement value is set in a tolerance mainly including the reference flow rate setting value when the flow rate setting value is the reference flow rate setting value, and a pulsation diagnosis part 7 for determining whether the liquid pump 1 is normal based on the flow rate measurement value under a setting state when it is determined that the flow rate measurement value is in the setting state.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an abnormality detection device and method for performing a failure diagnosis of a liquid pump.

  Analyze the pulsation frequency of the pressure of the hydraulic oil flowing out of the hydraulic pump, detect the number of rotations of the hydraulic pump per unit time, and use the detected rotation number and the analysis result of the pulsation frequency to calculate the hydraulic pump Patent Document 1 discloses a method of detecting an abnormality of a hydraulic pump by extracting a component of the rotational frequency of the hydraulic pump and determining whether or not the extracted component of the rotational frequency of the hydraulic pump is a normal value. ).

  Further, the pressure value of the oil flowing out of the hydraulic pump and the rotation phase of the hydraulic pump 2 when the pressure value of the oil is detected are detected, and the detected pressure value of the oil, the rotation phase of the hydraulic pump, A method is disclosed in which a pulsation waveform is extracted by modeling the relationship (1), and a failure diagnosis of the hydraulic pump is performed without being affected by variations in the rotation speed of the hydraulic pump (Patent Document 2).

  The techniques disclosed in Patent Literature 1 and Patent Literature 2 require highly specialized procedures and functions, and therefore have a problem that operators who can respond when failure diagnosis cannot be performed as expected are limited. Therefore, there is a need for a more simplified deterioration diagnosis technique, and improvements are required.

JP 2013-170509 A JP-A-2006-053308

  SUMMARY An advantage of some aspects of the invention is to provide an abnormality detection device and method that can simplify a configuration necessary for detecting an abnormality in a liquid pump.

  The abnormality detection device for a liquid pump according to the present invention is configured to previously store a reference flow rate set value for flow rate feedback control for controlling a valve so that a flow rate measured value of a liquid discharged from a liquid pump matches a flow rate set value. And determining whether the measured flow rate is settled within an allowable error range around the reference flow rate set value when the flow rate set value is the reference flow rate set value. And a setting state detecting unit configured as described above, and when the flow rate measurement value is determined to be in a settling state, is configured to determine whether the liquid pump is normal based on the flow rate measurement value in the setting state. And a diagnostic unit.

In one configuration example of the abnormality detection device for a liquid pump according to the present invention, the reference set value storage unit stores in advance a reference range of the valve opening degree together with the reference flow rate set value, and the set state detection unit. When the flow rate set value is the reference flow rate set value, the flow rate measured value is within an allowable error range around the reference flow rate set value, and the valve opening is within the reference range. , Wherein the flow measurement value is determined to be in a set state.
In one configuration example of the liquid pump abnormality detection device according to the present invention, the diagnosis unit sets the time-series data of the flow measurement value in the set state and the reference flow set value in a normal state of the liquid pump. In this case, it is determined whether or not the liquid pump is normal based on a template that is time-series data of past flow measurement values.
In one configuration example of the liquid pump abnormality detection device according to the present invention, the diagnosis unit sets the time-series data of the flow measurement value in the set state and the reference flow set value in a normal state of the liquid pump. And determining whether the liquid pump is normal based on a template that is time-series data of past flow measurement values when the valve opening is within the reference range. Things.

One configuration example of the abnormality detection device for a liquid pump according to the present invention is configured such that when an operator or a higher-level device instructs to switch to a provisional adjustment mode that allows the occurrence of a flow rate error, the flow rate measurement value is changed to the flow rate. A mode setting unit configured to switch the diagnostic mode from the normal mode to the set value to the tentative adjustment mode, and when the diagnostic mode is switched to the tentative adjustment mode, the flow rate set value is the reference flow set value. When the flow rate measurement value is within an allowable error range around the reference flow rate set value and the opening of the valve is out of the reference range, the flow rate set value is the reference flow rate set value. Assuming that the flow rate is within an allowable error range around the center, the flow rate set value is changed in a direction in which the valve opening approaches the reference range. When the flow rate set value change unit and the operator or a higher-level device are instructed to cancel the provisional adjustment mode, or when instructed to change the flow rate set value, the diagnostic mode is set to A mode release unit configured to switch to the normal mode.
Further, one configuration example of the abnormality detection device for a liquid pump of the present invention is configured such that when a predetermined timing is reached, the set state detection unit is configured to detect a deviation of the flow measurement value from the flow setting value. An execution management unit configured to issue an instruction, and a history information presenting unit configured to present a history of a deviation of the flow rate measurement value from the flow rate setting value detected by the settling state detection unit. An alarm output unit configured to output an alarm when an absolute value of a deviation of the flow rate measurement value from the flow rate setting value becomes equal to or greater than a specified amount.

  In one configuration example of the liquid pump abnormality detection device of the present invention, the diagnostic unit includes a flow rate measurement value acquisition unit configured to acquire time-series data of the flow rate measurement value in the set state, and the template The template storage unit configured to store in advance, the timing of the predetermined pulsation of the flow measurement value acquired by the flow measurement acquisition unit and the timing of the pulsation of the flow measurement value stored as the template A timing adjustment unit configured to perform a timing adjustment to match the time of the time-series data of the flow rate measurement value acquired by the flow rate measurement value acquisition unit with the template so as to match, and is stored as the template. The time series data of the flow measurement value after the timing adjustment is subtracted from the time series data of the flow measurement value at the same time. A subtraction processing unit configured to calculate a value obtained by accumulating the absolute value of the subtraction result of the subtraction processing unit; and a threshold value calculated by the accumulation processing unit. And a determination unit configured to determine that an abnormality has occurred in the liquid pump when the value exceeds the threshold value.

  Further, the abnormality detection method for a liquid pump according to the present invention may further include a flow rate feedback control system that controls a valve so that a flow rate measurement value of the liquid discharged from the liquid pump matches the flow rate setting value. At the set value, a first step of determining whether the flow rate measurement value is settled within an allowable error range around the reference flow rate set value, and the flow rate measurement value is determined to be in a settling state. And a second step of determining whether the liquid pump is normal based on the measured flow rate value in the set state.

  According to the present invention, when the flow rate set value is the reference flow rate set value, it is determined whether the flow rate measured value is set within an allowable error range centered on the reference flow rate set value, and the flow rate measured value is settled. When it is determined that the liquid pump is normal based on the flow rate measurement value in the set state, it is possible to simplify the configuration necessary for detecting the abnormality of the liquid pump.

FIG. 1 is a block diagram showing a configuration of a liquid pump abnormality detection device according to a first embodiment of the present invention. FIG. 2 is a flowchart illustrating the operation of the liquid pump abnormality detection device according to the first embodiment of the present invention. FIG. 3 is a diagram showing time-series data of flow rate measurement values when the liquid pump is in a normal state. FIG. 4 is a diagram illustrating an example of time-series data of a flow rate measurement value when abnormal pulsation occurs. FIG. 5 is a block diagram illustrating a configuration example of the pulsation diagnosis unit of the liquid pump abnormality detection device according to the first embodiment of the present invention. FIG. 6 is a flowchart illustrating a diagnosis process of the pulsation diagnosis unit of the liquid pump abnormality detection device according to the first embodiment of the present invention. FIG. 7 is a diagram illustrating an example in which the time-series data of the flow measurement value after the timing adjustment is subtracted from the time-series data of the flow measurement value registered as the template. FIG. 8 is a diagram illustrating an example in which the absolute values of the subtraction results of the flow measurement values are accumulated. FIG. 9 is a diagram illustrating another example of the time-series data of the flow measurement value when abnormal pulsation occurs. FIG. 10 is a diagram illustrating another example in which the time-series data of the flow measurement value after the timing adjustment is subtracted from the time-series data of the flow measurement value registered as the template. FIG. 11 is a diagram illustrating another example in which the absolute values of the subtraction results of the flow measurement values are accumulated. FIG. 12 is a block diagram showing the configuration of the liquid pump abnormality detection device according to the second embodiment of the present invention. FIG. 13 is a flowchart illustrating operations of a flow rate set value changing unit, a diagnosis execution mode setting unit, and a diagnosis execution mode canceling unit of the liquid pump abnormality detection device according to the second embodiment of the present invention. FIG. 14 is a block diagram showing the configuration of the liquid pump abnormality detection device according to the third embodiment of the present invention. FIG. 15 is a flowchart illustrating operations of the execution management unit, the history information presentation unit, and the alarm output unit of the liquid pump abnormality detection device according to the third embodiment of the present invention. FIG. 16 is a block diagram illustrating a configuration example of a computer that realizes the liquid pump abnormality detection device according to the first to third embodiments of the present invention.

[Principle 1 of the invention]
The inventor has focused on the fact that limiting the state of good reproducibility of the rotational speed of the pump as a diagnosis target can simplify the reduction of the influence of the rotational speed variation. Specifically, a state managed by feedback control can be used as a diagnosis target.

  The pump pressure is not subject to feedback control, and the flow rate is the control target. Therefore, it is preferable to execute diagnosis when the flow rate is stable. In this case, a modeling operation step for reducing the influence of the variation in the rotational speed and a particularly sophisticated arithmetic unit are not required, so that the configuration required for diagnosis can be simplified. For example, a state in which the flow rate is stable near a predetermined reference state (reference flow rate set value) of the flow rate feedback control is extracted, and pulsation is evaluated in that state. It is further preferable that the valve opening degree of the flow rate feedback control is also taken in as the condition of the reference state.

[Principle 2 of the invention]
When the valve opening is taken in as a condition of the reference state, if the flow rate has a margin with respect to the reference range and the valve opening is out of the reference range, the flow setting value is set so that the valve opening approaches the reference range. Provisionally adjust to the end of the range and execute diagnosis. Thereby, reproducibility is easily obtained.

[Principle 3 of the invention]
By periodically performing deterioration diagnosis of the pump, transmitting the diagnosis result to, for example, a higher-level device, and monitoring the diagnosis result with the higher-level device, it can be expected to detect a change in the state of the pump (such as occurrence of an abnormality). .

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment is an embodiment corresponding to the principle 1 of the invention described above. FIG. 1 is a block diagram illustrating a configuration of a liquid pump abnormality detection device according to the present embodiment. The abnormality detection device for the liquid pump includes a flow meter 2 for measuring a flow rate of the liquid discharged from the liquid pump 1, a valve 3 for adjusting the flow rate of the liquid, and a flow rate measurement value of the liquid so as to match the flow rate set value. A flow rate feedback control unit 4 for performing a flow rate feedback control for controlling the valve 3; a reference set value storage unit 5 for previously storing a reference flow set value for the flow rate feedback control; A settling state detector 6 that determines whether the measured value is settled within an allowable error range centered on the reference flow rate set value, and a flow measurement in this settled state when the flow rate measured value is determined to be settled. The liquid pump includes a pulsation diagnostic unit 7 that determines whether the liquid pump 1 is normal based on the value.

  FIG. 2 is a flowchart illustrating the operation of the liquid pump abnormality detection device according to the present embodiment. The flow meter 2, the valve 3, and the flow rate feedback control section 4 constitute a flow rate feedback control system. The flow rate feedback control unit 4 performs flow rate feedback control based on the flow rate measurement value PV measured by the flow meter 2 and the flow rate set value SP. Specifically, the flow rate feedback control unit 4 controls the valve 3 so that the flow rate measurement value PV matches the flow rate set value SP.

In the reference set value storage unit 5, a reference flow set value SPref of the flow rate feedback control is registered in advance. It is preferable that the reference flow set value SPref is a flow set value frequently set during the actual operation of the reference flow control. Further, it is preferable that the flow rate set value has a margin with respect to the measurement range so that the flow rate due to the pulsation does not exceed the measurement range even if the pulsation increases.
The settling state detection unit 6 determines that the current flow set value SP specified by the operator or a higher-level device (not shown) is the reference flow set value SPref, and that the flow measurement value PV is set to the reference flow set value SPref during a fixed settling determination time. When the ratio of time within a predetermined allowable error range (SPref ± α, α is a deviation) centered at or above a predetermined time rate threshold or more, the flow measurement value PV is determined to be in a settling state ( (YES in step S100 in FIG. 2).

  When the flow measurement value PV is determined to be in a settling state, the pulsation diagnosis unit 7 extracts time-series data of the flow measurement value PV during the setting (step S101 in FIG. 2). Based on the series data and the template which is the time series data of the past flow measurement value PV when the flow measurement value PV is settled at the reference flow setting value SPref in a normal state of the liquid pump 1, the liquid pump 1 Is diagnosed as normal (step S102 in FIG. 2).

The abnormality detection device repeatedly performs the above-described diagnostic operation during the operation of the liquid pump 1 until, for example, the operator gives an instruction to stop the operation.
Next, a specific example of a diagnosis method by the pulsation diagnosis unit 7 will be described with reference to FIGS. 3, 4, and 7 to 11. 3, 4, and 7 to 11 extremely express pulsation appearing in the flow rate measurement value PV for easy understanding. The following example is merely an example of a diagnostic method, and the present invention is not limited to the following method.

  FIG. 3 is a diagram showing time-series data of past flow measurement values PV when the liquid pump 1 is in a normal state, which is registered in advance in the pulsation diagnosis unit 7 as a template. In the example of FIG. 3, the reference flow rate set value SPref = 15.0 mL / min. 5 shows time-series data when the flow measurement value PV is settled.

[Diagnostic example 1]
FIG. 4 is a diagram illustrating an example of time-series data of the flow measurement value PV when abnormal pulsation occurs. The example of FIG. 4 is an example in which the cycle in which pulsation occurs in the flow measurement value PV is different from that of FIG.

  FIG. 5 is a block diagram illustrating a configuration example of the pulsation diagnosis unit 7, and FIG. 6 is a flowchart illustrating details of the diagnosis processing in step S <b> 102 of the pulsation diagnosis unit 7. The pulsation diagnosis unit 7 includes a flow measurement value acquisition unit 70 that acquires time-series data of flow measurement values in a set state, a template storage unit 71 that stores templates in advance, and a flow measurement measurement that is acquired by the flow measurement value acquisition unit 70. The time of the time series data of the flow measurement value PV acquired by the flow measurement value acquisition unit 70 so that the predetermined pulsation timing of the value PV matches the pulsation timing of the flow measurement value PV stored as a template. And a timing adjustment unit 72 for adjusting the timing of matching the flow rate with the template, and subtracting the time series data of the flow rate measurement value PV after the timing adjustment from the time series data of the flow rate measurement value PV stored as the template at the same time. A processing unit 73; an accumulation processing unit 74 for calculating a value obtained by accumulating the absolute value of the subtraction result of the subtraction processing unit 73; From a threshold storage unit 75 that stores in advance a threshold value for the threshold value, and a determination unit 76 that determines that an abnormality has occurred in the liquid pump 1 when the cumulative value calculated by the cumulative processing unit 74 exceeds the threshold value. Be composed.

  First, as described above, when the flow measurement value PV is determined to be in a settling state, the flow measurement value obtaining unit 70 of the pulsation diagnosis unit 7 obtains time-series data of the flow measurement value PV during the setting (step S101).

  Next, the timing adjustment unit 72 of the pulsation diagnosis unit 7 determines the predetermined pulsation timing of the flow measurement value PV acquired by the flow measurement acquisition unit 70 and the flow measurement value registered in advance in the template storage unit 71 as a template. After adjusting the time series data of the flow rate measurement value PV acquired by the flow rate measurement value acquisition section 70 along the time axis so as to match the pulsation timing of the PV, the timing adjustment is performed to match the time with the template ( FIG. 6 step S200).

  In order to actually perform such a timing adjustment, the timing adjustment unit 72 performs a predetermined pulsation of the flow measurement value PV acquired by the flow measurement acquisition unit 70 (for example, the first pulsation appears in the acquired time-series data). (Pulsation) peak timing is detected, and the flow rate measurement value acquired by the flow rate measurement value acquisition unit 70 is set such that the timing of this peak coincides with the timing of the pulsation peak of the flow rate measurement value PV registered in advance as a template. The time series data of the value PV may be shifted along the time axis.

Then, the timing adjustment unit 72 sets the start time of the template (start time of the diagnosis period) to 0 sec. From the end time of the template (end time of the diagnosis period) to 200 sec. The time information of the time series data of the flow measurement value PV acquired by the flow measurement value acquisition unit 70 is adjusted to the template so as to synchronize with the template.
In the example of FIG. 4 described above, the time 20 sec. 5 shows time-series data after the timing is adjusted so that the first pulsation appears in the flow measurement value PV.

Subsequently, the subtraction processing unit 73 of the pulsation diagnosis unit 7 subtracts the time series data of the flow measurement value PV after the timing adjustment from the time series data of the flow measurement value PV registered in advance as a template at the same time. (Step S201 in FIG. 6).
FIG. 7 shows a result obtained by subtracting the time series data of the flow rate measurement value PV after the timing adjustment from the time series data of the flow rate measurement value PV registered as a template, that is, the time series data of FIG. 4 from the time series data of FIG. Shows the result obtained by subtracting.

  Next, the accumulation processing unit 74 of the pulsation diagnosis unit 7 determines that the start time of the template (start time of the diagnosis period) is 0 sec. From the end time of the template (end time of the diagnosis period) to 200 sec. Until then, a value obtained by accumulating the absolute value of the subtraction result of the subtraction processing unit 73 is calculated (step S202 in FIG. 6). FIG. 8 shows a value obtained by accumulating the absolute values of the subtraction results shown in FIG.

  The determination unit 76 of the pulsation diagnosis unit 7 determines 0 sec. From 200 sec. If the cumulative value calculated by the cumulative processing unit 74 exceeds the threshold value (for example, 35.0 mL / min.) Registered in the threshold value storage unit 75 during the diagnosis period up to (YES in step S203 in FIG. 6), It is determined that an abnormality has occurred in the liquid pump 1 (step S204 in FIG. 6), and if the cumulative value during the diagnosis period is equal to or smaller than the threshold (NO in step S203), it is determined that the liquid pump 1 is normal (FIG. 6). 6 steps S205). In the example of FIG. 8, the accumulated value becomes equal to the threshold value of 35.0 mL / min. Therefore, it is determined that an abnormality has occurred in the liquid pump 1. Thus, the process of the pulsation diagnosis unit 7 ends.

[Diagnosis example 2]
Next, another diagnostic example will be described. FIG. 9 is a diagram illustrating another example of the time-series data of the flow measurement value PV when abnormal pulsation occurs. The example of FIG. 9 is an example in which the magnitude of occurrence of pulsation is different from that of FIG.

  The timing adjustment unit 72 of the pulsation diagnosis unit 7 performs the timing adjustment described above (Step S200 in FIG. 6). The example of FIG. 9 is the same as the template shown in FIG. 5 shows time-series data after the timing is adjusted so that the first pulsation appears in the flow measurement value PV.

  Subsequently, the subtraction processing unit 73 of the pulsation diagnosis unit 7 performs the above-described subtraction processing (Step S201 in FIG. 6). FIG. 10 shows the result of subtracting the time series data of the flow rate measurement value PV after the timing adjustment from the time series data of the flow rate measurement value PV registered as a template, that is, the time series data of FIG. 9 from the time series data of FIG. Shows the result obtained by subtracting.

The accumulation processing unit 74 of the pulsation diagnosis unit 7 performs the accumulation processing described above (Step S202 in FIG. 6). FIG. 11 shows a value obtained by accumulating the absolute values of the subtraction results shown in FIG.
The determination unit 76 of the pulsation diagnosis unit 7 performs the determination process described above (steps S203 to S205 in FIG. 6). In the example of FIG. 11, the accumulated value is close to the threshold 35.0 mL / min. Therefore, it is determined that an abnormality has occurred in the liquid pump 1. Thus, the process of the pulsation diagnosis unit 7 ends.

  Thus, in the present embodiment, the configuration necessary for detecting the abnormality of the liquid pump 1 can be simplified. When analyzing the pulsation frequency of the pressure of the liquid discharged from the liquid pump on the time axis, if the rotation speed of the liquid pump when detecting the pressure is not always constant, the relationship between the pulsation of the pressure and the time axis will be different. Will happen. In the technique disclosed in Patent Literature 2, the relationship between the pressure value of the liquid and the rotation phase of the liquid pump is modeled in order to avoid the influence of such a variation in the rotation speed of the liquid pump. Accordingly, the configuration of the device becomes complicated. On the other hand, in the present embodiment, since such modeling is not necessary, the configuration required for abnormality detection can be simplified.

  In the diagnostic examples 1 and 2, the reference flow rate set value SPref = 15.0 mL / min. It is assumed that when the flow measurement value PV is settled, the rotational state of the liquid pump 1 is reproduced in a state substantially equivalent to that when a normal template is created. More preferably, whether or not the opening degree of the valve 3 is within a reference range (for example, the opening degree of 35% to 40%) should also be adopted as the index for detecting the set state.

  That is, the settling state detection unit 6 determines that the current flow set value SP is the reference flow set value SPref, and the flow measured value PV is within a predetermined allowable error range around the reference flow set value SPref during a fixed settling determination time. When the ratio of the time during which the valve 3 is within the reference range is equal to or more than the predetermined time rate threshold and the opening degree of the valve 3 is within the reference range during the settling determination time, It is sufficient that the flow measurement value PV is determined to be in the set state (YES in step S100). The reference range of the valve opening may be registered in the reference set value storage unit 5 in advance. As for the template, the flow rate measurement value PV is settled at the reference flow rate setting value SPref when the liquid pump 1 is in a normal state, and at the same time, the time series of the flow rate measurement value PV when the opening degree of the valve 3 is within the reference range. Data may be used as a template.

[Second embodiment]
Next, a second embodiment of the present invention will be described. This embodiment is an embodiment corresponding to the above-described principle 2 of the invention. FIG. 12 is a block diagram showing a configuration of a liquid pump abnormality detection device according to the present embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals. The abnormality detection device according to the present embodiment includes a flowmeter 2, a valve 3, a flow rate feedback control unit 4, a reference set value storage unit 5, a settling state detection unit 6, a pulsation diagnosis unit 7, and a tentative diagnosis mode. When the mode is switched to the adjustment mode, the flow rate setting value SP is the reference flow rate setting value SPref, the flow rate measurement value PV is within an allowable error range around the reference flow rate setting value SPref, and the opening of the valve 3 is in the reference range. When the flow rate setting value SP deviates from the reference flow rate setting value SPref, the flow rate setting value SP is set in a direction in which the opening degree of the valve 3 approaches the reference range. The diagnostic mode is switched from the normal mode to the temporary adjustment mode when there is an instruction from the operator or a higher-level device to switch to the temporary adjustment mode and the flow rate set value changing unit 8 that changes the diagnostic mode to the temporary adjustment mode. The diagnosis for switching the diagnostic mode to the normal mode when the disconnection execution mode setting unit 9 and an instruction from the operator or the host device to release the provisional adjustment mode, or when an instruction to change the flow rate set value SP is issued. An execution mode release unit 10 is provided.

FIG. 13 is a flowchart for explaining the operations of the flow rate set value changing unit 8, the diagnosis execution mode setting unit 9, and the diagnosis execution mode canceling unit 10.
The diagnosis execution mode setting unit 9 suppresses the occurrence of the flow error when the operator or a higher-level device (not shown) instructs to switch to the provisional adjustment mode that allows the occurrence of the flow error (YES in step S300 in FIG. 13). The diagnostic mode is switched from the normal mode to the temporary adjustment mode (step S301 in FIG. 13).

  The normal mode is a mode in which the operation described in the first embodiment is performed. In the normal mode, the flow rate of the liquid pump 1 is controlled in a state where the flow rate feedback control is performed according to the flow rate set value SP specified by an operator or a higher-level device. This is a mode for performing diagnosis.

  When the diagnostic mode is switched to the provisional adjustment mode, the flow rate setting value changing unit 8 sets the current flow rate setting value SP designated by the operator or the host device to the reference flow rate setting value SPref (YES in step S302 in FIG. 13). , The flow measurement value PV is within a predetermined allowable error range (SPref ± α) centered on the reference flow setting value SPref (YES in step S303 in FIG. 13), and the opening of the valve 3 is out of the reference range. At this time (YES in step S304 in FIG. 13), the flow set value SP is set to the valve 3 on the premise that the flow set value SP is within an allowable error range (SPref ± α) centered on the reference flow set value SPref. Is changed by a predetermined width in a direction in which the opening degree approaches the reference range (step S305 in FIG. 13).

  In this manner, the flow rate is set in the direction in which the opening of the valve 3 approaches the reference range, assuming that the value is within the allowable error range (SPref ± α) centered on the reference flow rate set value SPref specified by the operator or the host device. Change the value SP. As described above, by temporarily adjusting the flow rate set value SP, the opening degree of the valve 3 can be made closer to the reference range, and can be made closer to the situation at the time when the template was obtained. Can be performed.

  Next, the diagnosis execution mode release unit 10 receives an instruction from the operator or the host device to release the provisional adjustment mode, or an instruction to change the flow rate set value SP (see step S306 in FIG. 13). YES), the diagnostic mode is switched to the normal mode (step S307 in FIG. 13).

  The flow rate setting value changing unit 8 receives an instruction from the operator or the host device to release the temporary adjustment mode, and if the flow rate setting value SP has been changed in the process of step S305, the flow rate setting value SP before the change is changed. Return to the reference flow rate set value SPref (step S308 in FIG. 13). In addition, when instructed to change the flow rate set value SP, the flow rate set value changing unit 8 changes the flow rate set value SP to a value specified by the operator or a higher-level device (step S308).

Hereinafter, an example of the provisional adjustment method of the present embodiment will be described. However, this is merely an example of the provisional adjustment method, and is not limited to the following method.
For example, when the reference flow rate set value SPref is 15.0 mL / min. It is assumed that the reference range of the opening degree of the valve 3 is 35% to 40%. The allowable error range (SPref ± α) near the reference flow rate set value SPref is 14.5 mL / min. ~ 15.5 mL / min. (That is, α = 0.5 mL / min.).

  Based on the above assumption, the flow rate set value SP = SPref = 15.0 mL / min. In contrast, the flow measurement value PV when not affected by the pulsation is 15.0 mL / min. It is assumed that the opening degree of the valve 3 is approximately 32%. When the mode is switched to the provisional adjustment mode, the mode becomes a mode in which a flow error may be intentionally generated. Therefore, the flow rate setting value changing unit 8 sets the opening of the valve 3 close to the reference range (when the opening of the valve 3 is large). ), The flow rate set value SP is set to, for example, 15.3 mL / min. Temporarily change to Accordingly, if the opening of the valve 3 becomes 35%, it is within the reference range, so that more appropriate pulsation diagnosis can be executed.

[Third embodiment]
Next, a third embodiment of the present invention will be described. This embodiment is an embodiment corresponding to the third principle of the present invention. FIG. 14 is a block diagram showing a configuration of a liquid pump abnormality detection device according to the present embodiment. The same components as those in FIG. 1 are denoted by the same reference numerals. The abnormality detection device according to the present embodiment includes a flow meter 2, a valve 3, a flow rate feedback control unit 4, a reference set value storage unit 5, a settling state detection unit 6, a pulsation diagnosis unit 7, and a predefined. When the timing comes, the execution management unit 11 instructs the settling state detection unit 6 to detect the deviation of the flow measurement value PV from the flow set value SP, and the flow rate detected by the settling state detection unit 6 A history information presenting unit 12 for presenting the history of the deviation of the flow measurement value PV from the set value SP, and outputting an alarm when the absolute value of the deviation of the flow measurement value PV from the flow set value SP becomes equal to or greater than a specified amount. An alarm output unit 13 is provided.

FIG. 15 is a flowchart illustrating the operation of the execution management unit 11, the history information presentation unit 12, and the alarm output unit 13.
When a predetermined timing is reached (YES in step S400 in FIG. 15), the execution management unit 11 detects the settling state, that is, the settling state detection unit 6 so as to detect a deviation of the flow measurement value PV from the flow set value SP. (Step S401 in FIG. 15).

  The history information presentation unit 12 presents the history of the deviation of the flow measurement value PV from the flow set value SP detected by the settling state detection unit 6 to the operator (Step S402 in FIG. 15).

  The alarm output unit 13 outputs an alarm when the absolute value of the deviation of the flow measurement value PV with respect to the flow set value SP is equal to or larger than a specified amount (YES in step S403 in FIG. 15) (step S404 in FIG. 15). Examples of the alarm output method include a method of displaying a message indicating the occurrence of an alarm, turning on an LED or the like, and transmitting information notifying the occurrence of an alarm to a higher-level device.

In this manner, the processing of steps S401 to S404 is performed periodically until, for example, an instruction to end the operation is given by the operator (YES in step S405 in FIG. 15).
In the present embodiment, the execution management unit 11, the history information presenting unit 12, and the alarm output unit 13 have been described as being applied to the first embodiment. However, the present embodiment is applied to the second embodiment. You may.

  Among the abnormality detection apparatuses of the first to third embodiments, at least the reference set value storage unit 5, the settling state detection unit 6, the pulsation diagnosis unit 7, the flow set value change unit 8, the diagnosis execution mode setting unit 9, and the diagnosis execution mode The release unit 10, the execution management unit 11, the history information presentation unit 12, and the alarm output unit 13 are realized by a computer having a CPU (Central Processing Unit), a storage device, and an interface, and a program that controls these hardware resources. can do.

  FIG. 16 shows a configuration example of this computer. The computer includes a CPU 200, a storage device 201, and an interface device (hereinafter, abbreviated as I / F) 202. The flow meter 2 and the flow rate feedback control unit 4 are connected to the I / F 202. In such a computer, a program for implementing the abnormality detection method of the present invention is stored in the storage device 201. The CPU 200 executes the processing described in the first to third embodiments according to the program stored in the storage device 201. Also, the flow rate feedback control unit 4 (controller) can be realized by a computer and a program as is well known.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a technology for performing a failure diagnosis of a liquid pump.

  DESCRIPTION OF SYMBOLS 1 ... Liquid pump, 2 ... Flow meter, 3 ... Valve, 4 ... Flow rate feedback control part, 5 ... Reference set value storage part, 6 ... Settling state detection part, 7 ... Pulsation diagnosis part, 8 ... Flow set value change part, 9: diagnosis execution mode setting unit, 10: diagnosis execution mode release unit, 11: execution management unit, 12: history information presentation unit, 13: alarm output unit, 70: flow rate measurement value acquisition unit, 71: template storage unit, 72 ... Timing adjuster 73, Subtractor 74, Accumulator 75, Threshold storage 76, Judgment

Claims (8)

A reference set value storage unit configured to previously store a reference flow set value of the flow rate feedback control for controlling the valve so that the flow rate measured value of the liquid discharged from the liquid pump matches the flow set value,
When the flow rate setting value is the reference flow rate setting value, a settling state detection unit configured to determine whether the flow rate measurement value is settled within an allowable error range around the reference flow rate setting value. When,
A diagnostic unit configured to determine whether the liquid pump is normal based on the flow measurement value in the set state when the flow measurement value is determined to be in the set state. Liquid pump abnormality detector. The abnormality detection device for a liquid pump according to claim 1,
The reference set value storage unit stores, in advance, the reference flow rate set value and a reference range of the valve opening degree,
The settling state detection unit is configured such that, when the flow rate set value is the reference flow rate set value, the flow rate measured value is within an allowable error range centered on the reference flow rate set value, and the opening degree of the valve is equal to the reference flow rate set value. An abnormality detection device for a liquid pump, wherein the flow rate measurement value is determined to be in a set state when the flow rate is within the range. The abnormality detection device for a liquid pump according to claim 1,
The diagnostic unit is a template that is time-series data of the flow measurement value in the settling state and time-series data of the past flow measurement value when the liquid pump is settled at the reference flow setting value in a normal state. And determining whether the liquid pump is normal on the basis of the above. The abnormality detecting device for a liquid pump according to claim 2,
The diagnostic unit, when the time series data of the flow rate measurement value in the settling state, the liquid pump is settled at the reference flow rate set value in a normal state, and the opening of the valve is within the reference range An abnormality detection device for the liquid pump, which determines whether or not the liquid pump is normal based on a template which is time-series data of past flow measurement values. The abnormality detection device for a liquid pump according to claim 2 or 4,
When the operator or a higher-level device instructs to switch to the provisional adjustment mode allowing the flow error, the diagnostic mode is switched from the normal mode in which the flow measurement value matches the flow setting value to the provisional adjustment mode. A mode setting unit configured as follows,
When the diagnostic mode is switched to the provisional adjustment mode, the flow rate set value is the reference flow rate set value, the flow rate measured value is within an allowable error range around the reference flow rate set value, and the valve When the opening degree is out of the reference range, the flow rate setting value is set on the premise that the flow rate setting value is within an allowable error range centered on the reference flow rate setting value. A flow set value changing unit configured to change in a direction approaching the reference range,
A mode configured to switch the diagnostic mode to the normal mode when instructed by an operator or a higher-level device to cancel the provisional adjustment mode, or when instructed to change the flow rate set value An abnormality detection device for a liquid pump, further comprising a release unit. The liquid pump abnormality detection device according to any one of claims 1 to 5,
When a predetermined timing is reached, an execution management unit configured to issue an instruction to the settling state detection unit to detect a deviation of the flow measurement value from the flow setting value,
A history information presenting unit configured to present a history of a deviation of the flow rate measurement value from the flow rate set value, detected by the settling state detection unit,
An abnormality output unit configured to output an alarm when an absolute value of a deviation of the flow rate measurement value from the flow rate set value is equal to or greater than a specified amount. apparatus. The abnormality detection device for a liquid pump according to claim 3 or 4,
The diagnostic unit includes:
A flow rate measurement value acquisition unit configured to obtain time-series data of the flow rate measurement value in the settling state,
A template storage unit configured to store the template in advance,
The flow measurement value acquired by the flow measurement value acquisition unit so that the predetermined pulsation timing of the flow measurement value acquired by the flow measurement value acquisition unit matches the pulsation timing of the flow measurement value stored as the template. A timing adjustment unit configured to perform timing adjustment to match the time of the time-series data of the measured flow rate value with the template,
A subtraction processing unit configured to subtract the time-series data of the flow measurement value after the timing adjustment from the time-series data of the flow measurement value stored as the template at each same time,
An accumulation processing unit configured to calculate a value obtained by accumulating the absolute value of the subtraction result of the subtraction processing unit;
A determination unit configured to determine that an abnormality has occurred in the liquid pump when the accumulated value calculated by the accumulation processing unit exceeds a threshold value. Detection device. In a flow rate feedback control system that controls a valve so that a flow rate measurement value of a liquid discharged from a liquid pump matches a flow rate setting value, when the flow rate setting value is a reference flow rate setting value, the flow rate measurement value is equal to the reference flow rate value. A first step of determining whether the flow rate is set within an allowable error range centered on the flow rate set value;
A second step of determining whether the liquid pump is normal based on the flow rate measurement value in the settled state when the flow rate measurement value is determined to be in a settling state. Anomaly detection method.