A method of proportional servo valve spool position control based on Lumberg state observer

Abstract

The invention discloses a proportional servo valve spool position control method based on a Lumberg state observer, and relates to the technical field of automatic control. The method adopts a spool position control system to work, and the system comprises a raw material tank, wherein industrial lubricating oil is stored in the raw material tank, a lubricating oil pump is connected to one side of the raw material tank, an output end of the lubricating oil pump is connected to an adjustment pipe body, the top and bottom of the adjustment pipe body are connected to a proportional servo valve, one end of the proportional servo valve is connected to a metering pump, one end of the metering pump located at the top of the adjustment pipe body is connected to a density detection end 1, and one end of the metering pump located at the bottom of the adjustment pipe body is connected to a density detection end 2, the density detection end 1 is connected to the bottom of the raw material tank, and the density detection end 2 is connected to the top of the raw material tank. The invention has the characteristic of accurate density adjustment.

Description

Technical Field

[0001] The invention relates to the field of automatic control technology, and in particular to a proportional servo valve core position control method based on a Romberg state observer. Background Art

[0002] A proportional servo valve is a device used to control the flow of a fluid (such as a liquid or gas). Its working principle is to achieve precise adjustment of flow and pressure through proportional control. The Lumberg state observer is a mathematical tool for state estimation in control systems and is widely used in state observation and estimation of linear dynamic systems.

[0003] During the production process of industrial lubricants, they are temporarily stored in tanks and then transported by pipelines. During the storage of lubricants, certain additives such as low-density polymers will slowly float to the oil surface, making their density lower than that of the lower layer, while heavier substances such as certain polar molecules and asphaltene may settle to the bottom, resulting in a higher density in the lower layer. Therefore, during pipeline transportation, the density of the lubricant is uneven due to different pumping positions. Under normal circumstances, a stirring device needs to be added between processes to make its density uniform, which will cause the production line to be too long. In addition, when the density is uneven, the measurement effect of the density sensor is not good. It is very necessary to design a proportional servo valve core position control method based on the Lumberg state observer with precise density adjustment. Summary of the invention

[0004] The object of the present invention is to provide a proportional servo valve spool position control method based on a Lumberg state observer to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a proportional servo valve spool position control method based on a Lumberg state observer, the method adopts a spool position control system to work, the system includes a raw material tank, the raw material tank stores industrial lubricating oil, one side of the raw material tank is through-connected with a lubricating oil pump, the output end of the lubricating oil pump is through-connected with an adjustment pipe body, the top and bottom of the adjustment pipe body are through-connected with a proportional servo valve, one end of the proportional servo valve is through-connected with a metering pumping pump, one end of the metering pumping pump located at the top of the adjustment pipe body is through-connected with a density detection terminal 1, and one end of the metering pumping pump located at the bottom of the adjustment pipe body is through-connected with a density detection terminal 2, the density detection terminal 1 is through-connected with the bottom of the raw material tank, and the density detection terminal 2 is through-connected with the top of the raw material tank.

[0006] According to the above technical solution, conical funnels are installed correspondingly on the top inner wall and the bottom inner wall of the adjustment tube body, one end of the conical funnel is connected to the proportional servo valve, a floating ball is arranged at the conical funnel located on the top inner wall of the adjustment tube body, and a sinking ball is arranged at the conical funnel located on the bottom inner wall of the adjustment tube body, the density of the floating ball is less than that of industrial lubricating oil, and the density of the sinking ball is greater than that of industrial lubricating oil.

[0007] According to the above technical solution, one end of the adjustment tube body is connected to the density detection end three, the density detection end one, the density detection end two and the density detection end three are each provided with a density sensor, and the lubricating oil pump and the metering pump are each provided with a flow sensor.

[0008] According to the above technical solution, the valve core position control system also includes a density data collection module, a supplementary pressure adjustment module, a valve core control module, a flow calculation module, a pumping control module, and a Long Berg state observation module. The supplementary pressure adjustment module is electrically connected to the valve core control module and the proportional servo valve. The flow calculation module and the pumping control module are electrically connected to the lubricating oil pump and the metering pump. The density data collection module is electrically connected to the density sensor. The density data collection module is used to collect the industrial lubricating oil density above the raw material tank, below the raw material tank and at the outlet of the adjustment tube body. The supplementary pressure adjustment module is used to calculate the outlet pressure of the proportional servo valve. The valve core control module is used to control the outlet pressure of the proportional servo valve by changing the position of the valve core of the proportional servo valve. The flow calculation module is used to calculate the pumping flow of the lubricating oil pump and the metering pump. The pumping control module is used to control the operation of the lubricating oil pump and the metering pump. The Long Berg state observation module is used to linearly adjust the outlet pressure of the proportional servo valve and the pumping flow of the metering pump according to the feedback data of the density detection terminal three.

[0009] According to the above technical solution, the following working steps are included:

[0010] S1. Setting the appropriate density range of industrial lubricants , and select the density lower than the appropriate density range as The floating ball and the density higher than the appropriate density range are The sinking ball;

[0011] S2. Set the outlet pressure of the proportional servo valve so that the outlet pressure of the proportional servo valve is balanced with the squeezing force of the sinking ball and the floating ball on the conical funnel within the appropriate density range, thereby forming the back pressure at the outlet of the proportional servo valve;

[0012] S3. When the back pressure at the outlet of the proportional servo valve disappears, the pumping control module controls the metering pump connected to the proportional servo valve to operate, detects the density of the supplementary industrial lubricant currently pumped through the density detection terminal 1 and the density detection terminal 2, calculates the pumping flow rate, and stops pumping after the pump reaches the set flow rate;

[0013] S4. The density of the industrial lubricating oil discharged from the outlet of the adjustment tube body is detected through the density detection terminal 3, and the subsequent proportional servo valve outlet pressure and the pumping flow of the metering pump are adjusted using the Lumberg state observation module.

[0014] According to the above technical solution, in S2, the industrial lubricating oil in the adjustment tube body is at the lower limit of the appropriate density range, so that the outlet pressure of the proportional servo valve above the adjustment tube body and the squeezing pressure of the upper float on the upper conical funnel are balanced, and the industrial lubricating oil in the adjustment tube body is at the upper limit of the appropriate density range, so that the outlet pressure of the proportional servo valve below the adjustment tube body and the squeezing pressure of the sinking ball on the lower conical funnel are balanced, so that the industrial lubricating oil in the adjustment tube body just squeezes out the sinking ball when the density is higher than the upper limit of the appropriate density range, and the industrial lubricating oil in the adjustment tube body just squeezes out the upper float when the density is lower than the lower limit of the appropriate density range.

[0015] According to the above technical solution, in S2, when the outlet pressure of the proportional servo valve above the adjusting tube body and the squeezing force of the upper floating ball on the upper conical funnel are balanced, the squeezing force of the upper floating ball on the upper conical funnel is , so set the upper proportional servo valve outlet pressure When the outlet pressure of the proportional servo valve below the pipe body is adjusted to balance the squeezing force of the sinking ball on the cone funnel below, the squeezing force of the sinking ball on the cone funnel below , so set the outlet pressure of the proportional servo valve below ,in is the conversion coefficient between extrusion force and buoyancy, is the volume of the floating ball and the sinking ball, is the gravity coefficient.

[0016] According to the above technical solution, in S3, the density of the supplementary industrial lubricant oil detected by the density detection end 1 is The density of the supplementary industrial lubricant oil detected by the density detection end 2 is , the detected pumping flow rate of the lubricating oil pump is When the metering pump located above the adjustment tube is in operation, the pumping flow rate is When the metering pump located below the adjustment tube is in operation, the pumping flow rate is ,in It is the pumping flow conversion factor, which should be used according to actual conditions.

[0017] According to the above technical solution, in S4, when the industrial lubricant density detected by the density detection terminal 3 is still less than When the density increase is insufficient, the increase The value is used to pump more supplementary industrial lubricating oil. When the industrial lubricating oil density detected by the density detection end 3 is still greater than When the density reduction is insufficient, the increase The value is to pump more supplementary industrial lubricants.

[0018] According to the above technical solution, in S4, after adjusting the pumping flow rate of the metering pump, continue to detect, if it is still In addition, when the industrial lubricant density detected by the density detection terminal 3 is still less than , and industrial lubricant density is still greater than When the pressure is increased, the outlet pressure of the proportional servo valve is increased and adjusted by the supplementary pressure adjustment module.

[0019] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention uses an upper floating ball and a lower sinking ball to provide intuitive feedback on the density of the industrial lubricating oil in the current pumping pipe section. When the density deviates from the normal range, the upper floating ball and the lower sinking ball are moved away, so that the industrial lubricating oil with a density higher or lower than the current pipe section is pumped from above or below the raw material tank, thereby balancing the density of the industrial lubricating oil to be within a certain range;

[0020] By calculating the outlet pressure and pumping volume of the proportional servo valve, the density at which the replenished industrial lubricant starts to be pumped and the size of the pumping volume can be accurately controlled, so that the density balance is highly accurate. Since the determination process on the balanced density does not rely on the density sensor, the density detection process is transferred to the relatively uniform parts of the upper and lower layers, avoiding the problem of poor measurement results using density sensors when the density is uneven. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention.

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0023] 1. Raw material tank; 2. Lubricating oil pump; 3. Adjustment tube; 4. Conical funnel; 5. Sinking ball; 6. Floating ball; 7. Proportional servo valve; 8. Metering pump; 9. Density detection terminal 1; 10. Density detection terminal 2; 11. Density detection terminal 3. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] See also Figure 1 The present invention provides a technical solution: a proportional servo valve spool position control method based on a Lumberg state observer, the method adopts a spool position control system to work, the system includes a raw material tank 1, the raw material tank 1 stores industrial lubricating oil, a lubricating oil pump 2 is connected to one side of the raw material tank 1, the output end of the lubricating oil pump 2 is connected to an adjustment tube body 3, the top and bottom of the adjustment tube body 3 are connected to a proportional servo valve 7, one end of the proportional servo valve 7 is connected to a metering pumping pump 8, one end of the metering pumping pump 8 located at the top of the adjustment tube body 3 is connected to a density detection terminal 1 9, one end of the metering pumping pump 8 located at the bottom of the adjustment tube body 3 is connected to a density detection terminal 2 10, the density detection terminal 1 9 is connected to the bottom of the raw material tank 1, and the density detection terminal 2 10 is connected to the top of the raw material tank 1;

[0026] A conical funnel 4 is installed on the top inner wall and the bottom inner wall of the adjusting tube body 3, one end of the conical funnel 4 is connected to the proportional servo valve 7, an upper floating ball 6 is arranged at the conical funnel 4 located on the top inner wall of the adjusting tube body 3, and a sinking ball 5 is arranged at the conical funnel 4 located on the bottom inner wall of the adjusting tube body 3, the density of the upper floating ball 6 is less than that of the industrial lubricating oil, and the density of the sinking ball 5 is greater than that of the industrial lubricating oil;

[0027] One end of the adjustment tube body 3 is connected to the density detection end 3 11, the density detection end 1 9, the density detection end 2 10 and the density detection end 3 11 are all provided with density sensors, and the lubricating oil pump 2 and the metering pump 8 are all provided with flow sensors;

[0028] The valve core position control system also includes a density data collection module, a supplementary pressure adjustment module, a valve core control module, a flow calculation module, a pumping control module, and a Long Berg state observation module. The supplementary pressure adjustment module is electrically connected to the valve core control module and the proportional servo valve 7. The flow calculation module and the pumping control module are electrically connected to the lubricating oil pump 2 and the metering pump 8. The density data collection module is electrically connected to the density sensor. The density data collection module is used to collect the industrial lubricating oil density above the raw material tank 1, below the raw material tank 1 and at the outlet of the adjustment tube body 3. The supplementary pressure adjustment module is used to calculate the outlet pressure of the proportional servo valve 7. The valve core control module is used to control the outlet pressure of the proportional servo valve 7 by changing the position of the valve core of the proportional servo valve 7. The flow calculation module is used to calculate the pumping flow of the lubricating oil pump 2 and the metering pump 8. The pumping control module is used to control the operation of the lubricating oil pump 2 and the metering pump 8. The Long Berg state observation module is used to linearly adjust the outlet pressure of the proportional servo valve 7 and the pumping flow of the metering pump 8 according to the feedback data of the density detection terminal 3 11;

[0029] The following steps are included:

[0030] S1. Setting the appropriate density range of industrial lubricants , and select the density lower than the appropriate density range as The floating ball and the density higher than the appropriate density range are The sinking ball;

[0031] S2. Set the outlet pressure of the proportional servo valve so that the outlet pressure of the proportional servo valve is balanced with the squeezing force of the sinking ball 5 and the floating ball 6 on the conical funnel 4 within a suitable density range, thereby forming a back pressure at the outlet of the proportional servo valve;

[0032] S3. When the back pressure at the outlet of the proportional servo valve disappears, the pumping control module controls the metering pump 8 connected to the proportional servo valve to operate, detects the density of the supplementary industrial lubricant currently pumped through the density detection terminal 1 9 and the density detection terminal 2 10, calculates the pumping flow rate, and stops pumping after the pump reaches the set flow rate;

[0033] S4, detecting the density of the industrial lubricating oil discharged from the outlet of the adjustment tube body 3 through the density detection terminal 3 11, and adjusting the subsequent outlet pressure of the proportional servo valve 7 and the pumping flow of the metering pump 8 by using the Lumberg state observation module;

[0034] In S2, the industrial lubricating oil in the adjusting tube body 3 is adjusted to the lower limit of the density range, so that the outlet pressure of the proportional servo valve above the adjusting tube body 3 and the squeezing force of the upper floating ball 6 on the upper conical funnel 4 are balanced, and the industrial lubricating oil in the adjusting tube body 3 is adjusted to the upper limit of the density range, so that the outlet pressure of the proportional servo valve below the adjusting tube body 3 and the squeezing force of the sinking ball 5 on the lower conical funnel 4 are balanced, so that the industrial lubricating oil in the adjusting tube body 3 just squeezes out the sinking ball 5 when the density is higher than the upper limit of the density range, and the industrial lubricating oil in the adjusting tube body 3 just squeezes out the upper floating ball 6 when the density is lower than the lower limit of the density range;

[0035] In S2, when the outlet pressure of the proportional servo valve above the adjusting tube body 3 and the squeezing force of the upper floating ball 6 on the upper conical funnel 4 are balanced, the squeezing force of the upper floating ball 6 on the upper conical funnel 4 is , so set the upper proportional servo valve outlet pressure When the outlet pressure of the proportional servo valve below the adjusting tube body 3 and the squeezing force of the sinking ball 5 on the lower conical funnel 4 are balanced, the squeezing force of the sinking ball 5 on the lower conical funnel 4 is , so set the outlet pressure of the proportional servo valve below ,in is the conversion coefficient between extrusion force and buoyancy, is the volume of the floating ball 6 and the sinking ball 5, is the gravity coefficient;

[0036] In S3, the density of the supplementary industrial lubricating oil detected by the density detection terminal 9 is The density of the supplementary industrial lubricant oil detected by the density detection terminal 10 is , the detected pumping flow rate of the lubricating oil pump 2 is When the metering pump 8 located above the adjustment tube 3 is in operation, the pumping flow rate is When the metering pump 8 located below the adjustment tube body 3 is in operation, the pumping flow rate is ,in It is the pumping flow conversion factor, which should be used according to the actual situation;

[0037] In S4, when the industrial lubricant density detected by the density detection terminal 11 is still less than When the density increase is insufficient, the increase The value is used to pump more supplementary industrial lubricating oil. When the industrial lubricating oil density detected by the density detection terminal 11 is still greater than When the density reduction is insufficient, the increase The value of pumping more supplementary industrial lubricant;

[0038] In S4, after adjusting the pumping flow rate of the metering pump 8, continue to detect. If it is still In addition, when the industrial lubricant density detected by the density detection terminal 11 is still less than , and industrial lubricant density is still greater than When the pressure is increased, the outlet pressure of the proportional servo valve 7 is increased and adjusted by the supplementary pressure adjustment module.

[0039] By using the upper floating ball and the lower sinking ball, the density of the industrial lubricant in the current pumping pipe section is intuitively fed back. When the density deviates from the normal range, the upper floating ball and the lower sinking ball are moved away, so that the industrial lubricant with a density higher or lower than the current pipe section is pumped from the top or bottom of the raw material tank, thereby balancing the density of the industrial lubricant to be within a certain range;

[0040] By calculating the outlet pressure and pumping volume of the proportional servo valve, the density at which the replenished industrial lubricant starts to be pumped and the size of the pumping volume can be accurately controlled, so that the density balance is highly accurate. Since the determination process on the balanced density does not rely on the density sensor, the density detection process is transferred to the relatively uniform parts of the upper and lower layers, avoiding the problem of poor measurement results using density sensors when the density is uneven.

[0041] 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.

[0042] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A proportional servo valve spool position control method based on a Lumberg state observer, characterized in that: The method operates by using a valve core position control system, the system comprising a raw material tank (1), wherein industrial lubricating oil is stored in the raw material tank (1), a lubricating oil pump (2) is connected to one side of the raw material tank (1), an output end of the lubricating oil pump (2) is connected to an adjustment tube body (3), the top and bottom of the adjustment tube body (3) are both connected to a proportional servo valve (7), one end of the proportional servo valve (7) is connected to a metering pumping pump (8), one end of the metering pumping pump (8) located at the top of the adjustment tube body (3) is connected to a density detection end 1 (9), one end of the metering pumping pump (8) located at the bottom of the adjustment tube body (3) is connected to a density detection end 2 (10), the density detection end 1 (9) is connected to the bottom of the raw material tank (1), and the density detection end 2 (10) is connected to the top of the raw material tank (1); Conical funnels (4) are correspondingly mounted on the top inner wall and the bottom inner wall of the adjustment tube body (3); one end of the conical funnel (4) is connected to a proportional servo valve (7); an upper floating ball (6) is arranged at the conical funnel (4) located on the top inner wall of the adjustment tube body (3); a lower sinking ball (5) is arranged at the conical funnel (4) located on the bottom inner wall of the adjustment tube body (3); the density of the upper floating ball (6) is less than that of industrial lubricating oil, and the density of the lower sinking ball (5) is greater than that of industrial lubricating oil.

2. The proportional servo valve spool position control method based on the Lumberg state observer according to claim 1 is characterized in that: One end of the adjustment tube body (3) is connected to a density detection end three (11), and density detection end one (9), density detection end two (10) and density detection end three (11) are each provided with a density sensor, and the lubricating oil pump (2) and the metering pump (8) are each provided with a flow sensor.

3. The proportional servo valve spool position control method based on the Lumberg state observer according to claim 2 is characterized in that: The valve core position control system further comprises a density data collection module, a supplementary pressure adjustment module, a valve core control module, a flow calculation module, a pumping control module, and a Lumberg state observation module. The supplementary pressure adjustment module is electrically connected to the valve core control module and the proportional servo valve (7). The flow calculation module and the pumping control module are electrically connected to the lubricating oil pump (2) and the metering pump (8). The density data collection module is electrically connected to the density sensor. The density data collection module is used to collect industrial lubricating oil density above the raw material tank (1), below the raw material tank (1) and at the outlet of the adjustment tube body (3). The supplementary pressure adjustment module is used to calculate the outlet pressure of the proportional servo valve (7), the valve core control module is used to control the outlet pressure of the proportional servo valve (7) by changing the position of the valve core of the proportional servo valve (7), the flow calculation module is used to calculate the pumping flow of the lubricating oil pump (2) and the metering pump (8), the pumping control module is used to control the operation of the lubricating oil pump (2) and the metering pump (8), and the Lumberg state observation module is used to linearly adjust the outlet pressure of the proportional servo valve (7) and the pumping flow of the metering pump (8) according to the feedback data of the density detection terminal three (11).

4. The proportional servo valve spool position control method based on the Lumberg state observer according to claim 3 is characterized in that: The following steps are included: S1. Setting the appropriate density range of industrial lubricants , and select the density lower than the appropriate density range as The floating ball and the density higher than the appropriate density range are The sinking ball; S2, setting the outlet pressure of the proportional servo valve so that the outlet pressure of the proportional servo valve is balanced with the squeezing force of the sinking ball (5) and the floating ball (6) on the conical funnel (4) within a suitable density range, thereby forming a back pressure at the outlet of the proportional servo valve; S3. When the back pressure at the outlet of the proportional servo valve disappears, the pumping control module controls the metering pump (8) connected to the proportional servo valve to operate, detects the density of the supplementary industrial lubricant currently being pumped through the density detection terminal 1 (9) and the density detection terminal 2 (10), calculates the pumping flow rate, and stops pumping after the pump reaches the set flow rate; S4. The density of the industrial lubricating oil discharged from the outlet of the adjustment tube body (3) is detected through the density detection terminal 3 (11), and the outlet pressure of the subsequent proportional servo valve (7) and the pumping flow rate of the metering pump (8) are adjusted using the Lumberg state observation module.

5. The proportional servo valve spool position control method based on the Lumberg state observer according to claim 4 is characterized in that: In the above S2, the industrial lubricating oil in the adjusting tube body (3) is adjusted to the lower limit of the density range, so that the outlet pressure of the proportional servo valve above the adjusting tube body (3) and the squeezing force of the upper floating ball (6) on the upper conical funnel (4) are balanced; the industrial lubricating oil in the adjusting tube body (3) is adjusted to the upper limit of the density range, so that the outlet pressure of the proportional servo valve below the adjusting tube body (3) and the squeezing force of the lower sinking ball (5) on the lower conical funnel (4) are balanced, so that the industrial lubricating oil in the adjusting tube body (3) just squeezes out the lower sinking ball (5) when the density is higher than the upper limit of the density range, and the industrial lubricating oil in the adjusting tube body (3) just squeezes out the upper floating ball (6) when the density is lower than the lower limit of the density range.

6. The proportional servo valve core position control method based on the Lumberg state observer according to claim 5 is characterized in that: In the above S2, when the outlet pressure of the proportional servo valve above the adjusting tube body (3) and the squeezing force of the upper floating ball (6) on the upper conical funnel (4) are balanced, the squeezing force of the upper floating ball (6) on the upper conical funnel (4) is , so set the upper proportional servo valve outlet pressure When the outlet pressure of the proportional servo valve below the adjusting tube body (3) and the squeezing force of the sinking ball (5) on the lower conical funnel (4) are balanced, the squeezing force of the sinking ball (5) on the lower conical funnel (4) is , so set the outlet pressure of the proportional servo valve below ,in is the conversion coefficient between extrusion force and buoyancy, is the volume of the floating ball (6) and the sinking ball (5), is the gravity coefficient.

7. The proportional servo valve core position control method based on the Lumberg state observer according to claim 6 is characterized in that: In S3, the density of the supplementary industrial lubricant oil detected by the density detection terminal 1 (9) is The density of the supplementary industrial lubricant oil detected by the density detection terminal 2 (10) is , the detected pumping flow rate of the lubricating oil pump (2) is When the metering pump (8) located above the adjustment tube (3) is in operation, the pumping flow rate is When the metering pump (8) located below the adjustment tube (3) is in operation, the pumping flow rate is ,in It is the pumping flow conversion factor, which should be used according to actual conditions.

8. The proportional servo valve core position control method based on the Lumberg state observer according to claim 7 is characterized in that: In S4, when the industrial lubricant density detected by the density detection terminal 3 (11) is still less than When the density increase is insufficient, the increase value to pump more additional industrial lubricating oil. When the industrial lubricating oil density detected by density detection end 3 (11) is still greater than When the density reduction is insufficient, the increase The value is to pump more supplementary industrial lubricants.

9. The proportional servo valve core position control method based on the Lumberg state observer according to claim 8 is characterized in that: In S4, after adjusting the pumping flow rate of the metering pump (8), the detection is continued. If the In addition, when the industrial lubricant oil density detected by the density detection terminal 3 (11) is still less than , and industrial lubricant density is still greater than When the pressure is increased, the outlet pressure of the proportional servo valve (7) is increased by the supplementary pressure adjustment module.

Images