Pump valve system control method and device

Abstract

The invention relates to a pump valve system control method and device. The method comprises the steps that the operation pressure difference value of an inlet and outlet mother pipe is collected; a target pressure difference value is preset, and a pressure difference value is obtained through calculation according to the operation pressure difference value and the target pressure difference value; outputting a control signal according to the pressure difference value through a PID (Proportion Integration Differentiation) algorithm; and controlling the pump through the control signal to obtain the control flow. According to the invention, the control of the pump valve system is more accurate, and the stable operation of the pump valve system can be maintained.

Description

Technical Field

[0001] The invention belongs to the field of pump and valve regulation, and in particular relates to a pump and valve system control method and device. Background Art

[0002] The pump-valve system uses a pump as a power output unit and a valve as a cut-off or flow / pressure regulation system to transport the medium to multiple flow-demand devices. Due to the large number of flow-demand devices and the large number of system operating conditions, the system control is relatively complex.

[0003] At present, the output of the pump is mostly controlled manually, and the flow of each device is matched by manually adjusting the valve opening in front of each flow demand device. This manual control method requires multiple attempts to achieve the required flow balance and temperature balance by manually controlling the output of the system pump and manually adjusting the valve opening in front of each flow demand device. Due to the large number of devices, adjusting the flow of a single device while the pump output remains unchanged will affect the flow of other devices. If the flow required by the system is adjusted by increasing the pump output, flow overshoot may occur. Overall, the adjustment accuracy is not high, the adjustment precision is poor, and the corresponding delay in the demand for flow demand devices is large. Summary of the invention

[0004] In view of the above deficiencies in the prior art, an object of the present invention is to provide a pump valve system control method and device.

[0005] The present invention provides a pump valve system control method, comprising:

[0006] S1: Collect the operating pressure difference of the inlet and outlet main pipes;

[0007] S2: Preset a target pressure difference value, and calculate a pressure difference value according to the operating pressure difference value and the target pressure difference value;

[0008] S3: Outputting a control signal according to the pressure difference through a PID algorithm;

[0009] S4: Control the pump through the control signal to obtain a controlled flow rate.

[0010] According to a pump valve system control method provided by the present invention, step S1 further comprises:

[0011] S11: Collect the inlet pressure value of the flow demand equipment;

[0012] S12: Collect the outlet pressure value of the flow demand equipment;

[0013] S13: Calculate and obtain an operating pressure difference value according to the inlet pressure value and the outlet pressure value.

[0014] According to a pump valve system control method provided by the present invention, the pressure difference in step S2 includes:

[0015] A positive pressure difference, wherein the positive pressure difference indicates that the operating pressure difference is greater than the target pressure difference;

[0016] A negative pressure difference value, wherein the negative pressure difference value indicates that the operating pressure difference value is less than the target pressure difference value.

[0017] According to a pump valve system control method provided by the present invention, when the pressure difference value is the positive pressure difference value, the control signal is a frequency reduction adjustment instruction;

[0018] When the pressure difference value is the negative pressure difference value, the control signal is a frequency increase regulation instruction.

[0019] According to a pump valve system control method provided by the present invention, step S4 further includes:

[0020] According to the required flows of multiple flow demanding devices, the control flow is controlled by adjusting the valve of the regulating device to supply flow to the flow demanding devices.

[0021] According to a pump valve system control method provided by the present invention, a plurality of device regulating valves are arranged in parallel.

[0022] The present invention also provides a pump valve system control device, comprising:

[0023] Pressure difference acquisition module: used to collect the operating pressure difference value of the inlet and outlet main pipes;

[0024] Pressure difference control module: preset a target pressure difference value, calculate the pressure difference value according to the operating pressure difference value and the target pressure difference value; also used to output a control signal according to the pressure difference value through a PID algorithm; also used to control the pump through the control signal to obtain a control flow.

[0025] According to a pump valve system control device provided by the present invention, the pressure difference acquisition module comprises:

[0026] An inlet pressure gauge, which is arranged at the inlet main pipe of the flow demand device and is used to collect the inlet pressure value of the flow demand device;

[0027] An outlet pressure gauge, which is arranged at the outlet main pipe of the flow demand device and is used to collect the outlet pressure value of the flow demand device;

[0028] The inlet pressure gauge and the outlet pressure gauge are both remotely and wirelessly connected to the pressure difference control module.

[0029] According to a pump valve system control device provided by the present invention, the pressure difference control module is configured as a pressure difference PID controller.

[0030] A pump valve system control device according to the present invention also includes:

[0031] Equipment valve adjustment;

[0032] The equipment regulating valve is arranged corresponding to the flow demand equipment, and multiple equipment regulating valves are arranged in parallel on the inlet sub-pipes of multiple flow demand equipment, and are used to supply flow to the flow demand equipment according to the required flow of the multiple flow demand equipment.

[0033] The present invention provides a pump valve system control method and device. By collecting the operating pressure difference value of the inlet and outlet main pipes and comparing it with the preset target pressure difference value, the pressure difference value can be accurately calculated. Based on the comparison between the actual operating data and the preset target value, the control can be more accurate, which is helpful to maintain the stable operation of the system; secondly, according to the calculated pressure difference value, the corresponding control signal is output through the PID algorithm. Whether it is a frequency reduction adjustment instruction or a frequency increase adjustment instruction, the dynamic adjustment of the pump can be realized, and the system pressure change can be quickly responded to, the pressure is kept stable, and the flexibility and response speed of the system are improved; the present invention can avoid unnecessary energy consumption through precise pressure difference control and dynamic adjustment. When the operating pressure difference value is higher than the target value, the pump frequency is reduced to reduce energy consumption; when the operating pressure difference value is lower than the target value, the pump frequency is increased to meet the flow demand. It is helpful to achieve the rational use of energy and improve the energy efficiency of the system; in addition, the method of the present invention is not only applicable to the control of a single flow demand device, but also can control the total control flow by adjusting the device valve according to the required flow of multiple flow demand devices, so that the system can adapt to the changes of different flow demands, and improve the flexibility and applicability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are only used to illustrate specific embodiments and are not considered to limit the present invention. In the entire drawings, the same reference symbols represent the same components. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0035] Figure 1 A schematic flow chart of a pump valve system control method provided by an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of the structure of a pump valve system control device provided by an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of the implementation and deployment of a pump valve system control device provided in an embodiment of the present invention.

[0038] Reference numerals:

[0039] 100, differential pressure acquisition module; 200, differential pressure control module; 300, equipment regulating valve; 400, pump; 500, production equipment;

[0040] 110. Inlet pressure gauge; 120. Outlet pressure gauge. DETAILED DESCRIPTION

[0041] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work should fall within the scope of protection of the present invention.

[0042] Furthermore, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts disclosed in the present invention.

[0043] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. The terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0044] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of methods and systems consistent with some aspects of the present invention as detailed in the appended claims.

[0045] The embodiments of the present invention are described below with reference to the accompanying drawings.

[0046] like Figure 1 As shown, the present invention provides a pump valve system control method, comprising:

[0047] S1: Collect the operating pressure difference of the inlet and outlet main pipes.

[0048] Wherein, step S1 further comprises:

[0049] S11: Collect the inlet pressure value of the flow demand equipment;

[0050] S12: Collect the outlet pressure value of the flow demand equipment;

[0051] S13: Calculate and obtain an operating pressure difference value according to the inlet pressure value and the outlet pressure value.

[0052] Furthermore, in step S11, the inlet pressure value of the flow demand device is collected, with the purpose of understanding the pressure condition at the inlet of the flow demand device, and the pressure value of this point is collected and recorded in real time through the pressure sensor installed at the inlet of the device; in step S12, the outlet pressure value of the flow demand device is collected, with the purpose of understanding the pressure condition at the outlet of the flow demand device, which together with the inlet pressure value constitutes an important parameter for evaluating the operating status of the system. Similarly, the pressure value of this point is collected and recorded in real time through the pressure sensor installed at the outlet of the device, and finally, based on the inlet and outlet pressure values, the difference between them is calculated, that is, the inlet pressure value and the outlet pressure value collected in steps S11 and S12 are subtracted to obtain the operating pressure difference value.

[0053] S2: Preset a target pressure difference value, and calculate a pressure difference value according to the operating pressure difference value and the target pressure difference value.

[0054] Wherein, the pressure difference value in step S2 includes:

[0055] A positive pressure difference value indicates that the operating pressure difference value is greater than the target pressure difference value; a negative pressure difference value indicates that the operating pressure difference value is less than the target pressure difference value.

[0056] Furthermore, the pressure difference value refers to the difference between the operating pressure difference value and the target pressure difference value, which reflects the deviation between the current system operating state and the target state.

[0057] A positive pressure difference indicates that the pressure currently provided by the system exceeds the target value. A positive pressure difference prompts us to reduce the output power of the pump or adjust other related parameters to reduce the pressure of the system. A negative pressure difference indicates that the pressure currently provided by the system is insufficient. A negative pressure difference prompts us to increase the output power of the pump or adjust other related parameters to increase the pressure of the system.

[0058] S3: Outputting a control signal according to the pressure difference through a PID algorithm.

[0059] When the pressure difference value is the positive pressure difference value, the control signal is a frequency reduction regulation instruction; when the pressure difference value is the negative pressure difference value, the control signal is a frequency increase regulation instruction.

[0060] Furthermore, in step S3, the input of the applied PID algorithm is the pressure difference, and the output is a control signal (a frequency reduction regulation instruction or a frequency increase regulation instruction). The PID algorithm calculates the control signal through three links of proportional, integral and differential according to the input pressure difference; in the proportional link, a part of the control signal is directly calculated according to the size of the pressure difference. The larger the pressure difference, the larger the control signal (for a positive pressure difference, a larger frequency reduction regulation is required; for a negative pressure difference, a larger frequency increase regulation is required); a part of the control signal = proportional coefficient Kp × pressure difference; in the integral link, the purpose is to eliminate the steady-state error, mainly by integrating the past pressure difference to obtain a pressure difference. The control signal related to the duration of the pressure difference helps to gradually adjust the system to reach the target pressure difference when the pressure difference exists for a long time. The specific integral term integral coefficient Ki×∫(pressure difference dt). In practical applications, since computer control is sampling control, the integral term is usually calculated by discretization, that is, the rectangular method numerical integration approximation is used instead of integration; in the differential link, the purpose is to predict the trend of the pressure difference change, give a control signal in advance to suppress the occurrence of deviations, and obtain a control signal related to the rate of change of the pressure difference by performing differential operations on the pressure difference. The specific calculation is differential term = differential coefficient Kd×(current pressure difference - pressure difference at the last sampling time) / sampling period. This helps to make adjustments in advance when the system is about to experience a large pressure difference change, thereby improving the response speed and stability of the system.

[0061] Finally, the synthesis of the control signal is a linear combination of the output quantities of the three links of proportion, integration and differentiation, that is, control signal = proportional term + integral term + differential term, and then according to the size and direction of the control signal, the corresponding frequency reduction adjustment instruction or frequency increase adjustment instruction is output. If the control signal is positive and large, the frequency increase adjustment instruction is output; if the control signal is negative or small (but greater than a certain threshold to avoid misoperation), the frequency reduction adjustment instruction is output.

[0062] S4: Control the pump through the control signal to obtain a controlled flow rate.

[0063] When the pressure difference between the inlet pressure gauge and the outlet pressure gauge is lower than the set pressure difference target value, the pressure difference PID controller will increase the frequency of the pump, increase the speed of the pump, increase the outlet pressure and increase the flow rate. The square of the flow rate is almost proportional to the pipeline resistance. When the flow rate increases and the opening of the inlet regulating valve of the flow demand equipment remains unchanged, the pressure difference between the inlet pressure gauge and the outlet pressure gauge will increase until the set pressure difference is reached; conversely, when the pressure difference between the inlet pressure gauge and the outlet pressure gauge is higher than the set pressure difference target value, the pressure difference PID controller will reduce the frequency of the pump, reduce the speed and reduce the flow rate. If the opening of the inlet regulating valve of the flow demand equipment remains unchanged, the pressure difference between the inlet pressure gauge and the outlet pressure gauge will decrease until the set pressure difference is reached.

[0064] Step S4 also includes:

[0065] According to the required flows of multiple flow demanding devices, the control flow is controlled by adjusting the valve of the regulating device to supply flow to the flow demanding devices.

[0066] Among them, multiple equipment regulating valves are set in parallel.

[0067] like Figure 2 and Figure 3 As shown, the present invention also provides a pump valve system control device, comprising:

[0068] The pressure difference collection module 100 is used to collect the operating pressure difference value of the inlet and outlet main pipes.

[0069] Wherein, the pressure difference acquisition module 100 includes:

[0070] The inlet pressure gauge 110 is arranged at the inlet main pipe of the flow demand device and is used to collect the inlet pressure value of the flow demand device.

[0071] The outlet pressure gauge 120 is arranged at the outlet main pipe of the flow demand device and is used to collect the outlet pressure value of the flow demand device.

[0072] The inlet pressure gauge 110 and the outlet pressure gauge 120 are both remotely and wirelessly connected to the pressure difference control module.

[0073] The pressure difference control module 200: presets a target pressure difference value, and calculates a pressure difference value according to the operating pressure difference value and the target pressure difference value; is also used to output a control signal according to the pressure difference value through a PID algorithm; is also used to control a pump through the control signal to obtain a control flow.

[0074] Wherein, the pressure difference control module 200 is configured as a pressure difference PID controller.

[0075] Among them, it also includes:

[0076] Equipment regulating valve 300;

[0077] The equipment regulating valve 300 is arranged corresponding to the flow demand equipment, and multiple equipment regulating valves 300 are arranged in parallel on the inlet sub-pipes of multiple flow demand equipment, and are used to supply flow to the flow demand equipment according to the required flow of the multiple flow demand equipment.

[0078] Further, such as Figure 3 As shown, the control device of the present invention includes during application: a pump 400, production equipment 500, an inlet pressure gauge 110, an equipment regulating valve 300, various flow demand devices (users), a spare outlet pressure gauge 120, a differential pressure control module 200 (differential pressure PID controller), a communication line from the inlet pressure gauge of the flow demand device to the differential pressure PID controller, a communication line from the outlet pressure gauge of the flow demand device to the differential pressure PID controller, and a communication line from the differential pressure PID controller to the frequency adjustment instruction of the pump.

[0079] When the pressure difference between the inlet pressure gauge 110 and the outlet pressure gauge 120 is lower than the set pressure difference target value, the pressure difference PID controller, i.e., the pressure difference control module 200, will increase the frequency of the pump 400, increase the speed of the pump 400, increase the outlet pressure and increase the flow rate, and the square of the flow rate is almost proportional to the pipeline resistance. When the flow rate increases and the opening of the inlet regulating valve of the flow demand device remains unchanged, the pressure difference between the inlet pressure gauge 110 and the outlet pressure gauge 120 will increase until the set pressure difference is reached. Conversely, when the pressure difference between the inlet pressure gauge 110 and the outlet pressure gauge 120 is higher than the set pressure difference target value, the pressure difference PID controller will reduce the frequency of the pump 400, reduce the speed, and reduce the flow rate. If the opening of the inlet regulating valve of the flow demand device remains unchanged, the pressure difference between the inlet pressure gauge 110 and the outlet pressure gauge 120 will decrease until the set pressure difference is reached.

[0080] The pump maintains the pressure difference of the inlet and outlet main pipes of the flow demand equipment, and adjusts the medium flow required by each flow demand equipment by adjusting the regulating valve 300 of each flow demand equipment. When there is a device in the flow demand equipment that needs to increase the required flow, the operator manually adjusts the regulating valve corresponding to the corresponding equipment. Under the condition of a certain pressure difference, the valve opens wider, the pipeline resistance decreases, and the flow of the corresponding equipment increases; conversely, the operator manually closes the corresponding regulating valve of the corresponding equipment, and the flow of the corresponding equipment decreases.

[0081] The present invention provides a control method and ambition for a pump-valve system, which sets a pump pressure differential PID controller for the pump-valve system, which has obvious advantages over the operation mode of purely manual control of pump speed and manual control of valve opening. Because all flow demand devices are set in parallel on the pipeline, and the pressure differential of each branch is the same, the pump is used to automatically maintain the pressure differential of the inlet and outlet main pipes of the flow demand device. The branch where a single flow demand device is located performs flow regulation, which will not affect the flow of other branches, avoiding the situation of flow overshoot when manually adjusting the pump speed. The regulation process is more accurate and faster, and it also avoids mutual interference in the flow regulation process of each flow demand device.

[0082] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. Any changes or replacements that can be easily thought of by those skilled in the art within the technical scope disclosed in the present invention should be covered within the protection scope of the present invention.

Claims

1. A pump valve system control method, characterized in that: include: S1: Collect the operating pressure difference of the inlet and outlet main pipes; S2: Preset a target pressure difference value, and calculate a pressure difference value according to the operating pressure difference value and the target pressure difference value; S3: Outputting a control signal according to the pressure difference through a PID algorithm; S4: Control the pump through the control signal to obtain a controlled flow rate.

2. A pump valve system control method according to claim 1, characterized in that: Step S1 further comprises: S11: Collect the inlet pressure value of the flow demand equipment; S12: Collect the outlet pressure value of the flow demand equipment; S13: Calculate and obtain an operating pressure difference value according to the inlet pressure value and the outlet pressure value.

3. A pump valve system control method according to claim 1, characterized in that: The pressure difference in step S2 includes: A positive pressure difference, wherein the positive pressure difference indicates that the operating pressure difference is greater than the target pressure difference; A negative pressure difference value, wherein the negative pressure difference value indicates that the operating pressure difference value is less than the target pressure difference value.

4. A pump valve system control method according to claim 3, characterized in that: When the pressure difference value is the positive pressure difference value, the control signal is a frequency reduction adjustment instruction; When the pressure difference value is the negative pressure difference value, the control signal is a frequency increase regulation instruction.

5. A pump valve system control method according to claim 1, characterized in that: Step S4 also includes: According to the required flows of multiple flow demanding devices, the control flow is controlled by adjusting the valve of the regulating device to supply flow to the flow demanding devices.

6. A pump valve system control method according to claim 5, characterized in that: Multiple equipment regulating valves are set in parallel.

7. A pump valve system control device, characterized in that: include: Pressure difference acquisition module: used to collect the operating pressure difference value of the inlet and outlet main pipes; Pressure difference control module: preset a target pressure difference value, calculate the pressure difference value according to the operating pressure difference value and the target pressure difference value; also used to output a control signal according to the pressure difference value through a PID algorithm; also used to control the pump through the control signal to obtain a control flow.

8. A pump valve system control device according to claim 7, characterized in that: The pressure difference acquisition module comprises: An inlet pressure gauge, which is arranged at the inlet main pipe of the flow demand device and is used to collect the inlet pressure value of the flow demand device; An outlet pressure gauge, which is arranged at the outlet main pipe of the flow demand device and is used to collect the outlet pressure value of the flow demand device; The inlet pressure gauge and the outlet pressure gauge are both remotely and wirelessly connected to the pressure difference control module.

9. A pump valve system control device according to claim 7, characterized in that: The pressure difference control module is configured as a pressure difference PID controller.

10. A pump valve system control device according to claim 7, characterized in that: Also includes: Equipment valve adjustment; The equipment regulating valve is arranged corresponding to the flow demand equipment, and multiple equipment regulating valves are arranged in parallel on the inlet sub-pipes of multiple flow demand equipment, and are used to supply flow to the flow demand equipment according to the required flow of the multiple flow demand equipment.

Images