CN113757197B - Constant pressure control method of pump station - Google Patents
Constant pressure control method of pump station Download PDFInfo
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- CN113757197B CN113757197B CN202110829868.2A CN202110829868A CN113757197B CN 113757197 B CN113757197 B CN 113757197B CN 202110829868 A CN202110829868 A CN 202110829868A CN 113757197 B CN113757197 B CN 113757197B
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- pressure
- pump station
- hydraulic
- throttle valve
- proportional throttle
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
- F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
- F15B11/05—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed specially adapted to maintain constant speed, e.g. pressure-compensated, load-responsive
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B15/00—Fluid-actuated devices for displacing a member from one position to another; Gearing associated therewith
- F15B15/08—Characterised by the construction of the motor unit
- F15B15/14—Characterised by the construction of the motor unit of the straight-cylinder type
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a constant-pressure control method of a pump station. On the basis of the existing hydraulic support pump station, a proportional throttle valve or a variable hydraulic motor is set in a bypass of the pump station, and constant pressure control of the pump station is realized by adjusting the opening of the proportional throttle valve or the displacement of the variable hydraulic motor. The method can effectively reduce the hydraulic impact of the system and improve the speed and position control performance of the hydraulic support.
Description
Technical Field
The invention relates to a pump station control method, in particular to a constant pressure control method of a pump station, which is particularly suitable for a multi-pump linkage hydraulic system used in coal mining.
Background
The pump station is a power source for supplying liquid to a hydraulic support of the fully mechanized mining face. The flow required by the hydraulic support of the fully mechanized mining face is large, so that a multi-pump linkage control is often adopted in a traditional hydraulic support pump station to supply liquid to the system. The hydraulic pump loads or unloads in sequence according to the pressure required by the system: when the pressure is lower than the required pressure, loading the next hydraulic pump and increasing the liquid supply flow; when the pressure is higher than the required pressure, an operating hydraulic pump is unloaded, and the feed flow is reduced. The outlet pressure of the pump station fluctuates in a certain range, and the pressure fluctuation generates larger pressure fluctuation at the inlet of the control valve of the hydraulic support after long-distance liquid supply or the plurality of hydraulic pump sets are opened in sequence, so that the speed and position control performance of the hydraulic support is influenced.
Disclosure of Invention
In order to solve the problems in the background art, the invention provides a constant pressure control method of a pump station, which solves the problem that the speed and position control performance of a hydraulic support are influenced by large pressure fluctuation generated at an inlet of a control valve of the hydraulic support after pressure fluctuation liquid supply caused by sequential opening of hydraulic pump sets in the pump station.
The technical scheme adopted by the invention is as follows:
a proportional throttle valve or a variable hydraulic motor is connected in parallel between an outlet of the pump station and an oil tank, one end of the proportional throttle valve or the variable hydraulic motor is connected with an outlet pipeline of the pump station, and the other end of the proportional throttle valve or the variable hydraulic motor is connected with the oil tank; and the outlet pipeline of the pump station is provided with a pressure sensor, the pressure sensor is used for detecting the pressure of the outlet pipeline of the pump station and feeding the pressure back to the controller, and the controller outputs a proportional throttle valve opening control signal or a variable hydraulic motor displacement signal to realize the control of the proportional throttle valve or the variable hydraulic motor.
The pump station is a hydraulic device or equipment for outputting a hydraulic power source.
The hydraulic support is a hydraulic actuator.
The electro-hydraulic valve bank is used for controlling the hydraulic support and comprises a valve used for controlling the inflow of the hydraulic support.
The pump station comprises a plurality of hydraulic pump sets which are connected in parallel, and the plurality of hydraulic pump sets are sequentially loaded and unloaded.
An outlet of the pump station is connected to an inlet end of the electro-hydraulic valve group, and an outlet end of the electro-hydraulic valve group is output to the hydraulic support.
The constant pressure control method of the invention realizes the constant pressure control by a pressure closed loop control.
Obtaining the expected pressure of an outlet of a pump station according to the position and speed requirements of the hydraulic support; the method comprises the steps that the current pipeline pressure is detected through a pressure sensor arranged on an outlet pipeline of a pump station, the expected pressure is compared with the current pipeline pressure to obtain a differential pressure, the differential pressure is input into a PID controller, the differential pressure is converted into an opening control signal of a proportional throttle valve or a displacement control signal of a variable hydraulic motor through the PID controller, the opening of the proportional throttle valve or the displacement of the variable hydraulic motor is adjusted through the opening control signal/displacement control signal to further change the flow passing through the proportional throttle valve or the variable hydraulic motor, the oil pressure at the outlet of the pump station is kept constant at all times, and finally constant pressure control of the outlet of the pump station is achieved.
The hydraulic support is a hydraulic actuator in a coal mining hydraulic system.
When one hydraulic pump set is loaded or unloaded each time, the pressure detected by the pressure sensor 10 is fed back to the opening of the proportional throttle valve or the variable hydraulic motor for quick response adjustment, so that the oil pressure of an outlet pipeline of the pump station is kept constant all the time.
The beneficial effects of the invention are:
on the basis of the existing hydraulic support pump station, a proportional throttle valve or a variable hydraulic motor is arranged in a bypass of the pump station, and the constant pressure control of the pump station is realized by adjusting the opening of the proportional throttle valve or the displacement of the variable hydraulic motor. The method can effectively reduce the hydraulic impact of the system and improve the speed and position control performance of the hydraulic actuator.
The method can maintain the stability of the system pressure, reduce pressure impact, improve the reliability and the service life of the pump station, and improve the speed and the position control performance of the hydraulic support.
Drawings
FIG. 1 is a schematic view of a constant pressure pumping station according to the present invention.
Fig. 2 is a schematic diagram of a constant voltage control method according to the present invention.
Fig. 3 is an embodiment of the present invention.
Fig. 4 is a schematic diagram of a control method according to an embodiment of the present invention.
Fig. 5 is another embodiment of the present invention.
Fig. 6 is a schematic diagram of a control method according to another embodiment of the present invention.
In the figure: the hydraulic control system comprises a motor 1, a first hydraulic pump 2, a filter 3, a first overflow valve 4, a second hydraulic pump 5, a second overflow valve 6, a third hydraulic pump 7, a third overflow valve 8, an oil tank 9, a pressure sensor 10, a proportional throttle valve/variable hydraulic motor 11, an electro-hydraulic valve group 12, a hydraulic support 13, a proportional throttle valve 14 and a variable hydraulic motor 15.
Detailed Description
The invention is described in further detail below with reference to the figures and the embodiments.
As shown in figure 1, an outlet of a pump station is connected to an inlet end of an electro-hydraulic valve group 12, an outlet end of the electro-hydraulic valve group 12 is output to a hydraulic support 13, and an oil discharge end of an oil cylinder in the hydraulic support 13 is connected with an oil return tank. A proportional throttle valve or a variable hydraulic motor is arranged between an outlet of a pump station and an oil tank, one end of a proportional throttle valve or a variable hydraulic motor 11 is connected with an outlet pipeline of the pump station, and the other end of the proportional throttle valve or the variable hydraulic motor is connected with the oil tank; and the outlet pipeline of the pump station is provided with a pressure sensor 10, the pressure sensor 10 is used for detecting the pressure of the outlet pipeline of the pump station and feeding the pressure back to the controller, and the controller outputs a proportional throttle valve opening control signal or a variable hydraulic motor displacement signal to realize the control of the proportional throttle valve or the variable hydraulic motor.
The pump station comprises a plurality of hydraulic pump sets which are connected in parallel, the input ends of the hydraulic pump sets are connected to the oil tank, the output ends of the hydraulic pump sets are connected together, and the hydraulic pump sets are sequentially loaded and unloaded.
As shown in fig. 2, the desired pressure at the outlet of the pump station is obtained according to the position and speed requirements of the hydraulic support; the method comprises the steps that the current pipeline pressure is detected through a pressure sensor arranged on an outlet pipeline of a pump station, the expected pressure is compared with the current pipeline pressure to obtain a differential pressure, the differential pressure is input into a PID controller, the differential pressure is converted into an opening control signal of a proportional throttle valve or a displacement control signal of a variable hydraulic motor through the PID controller, the opening of the proportional throttle valve or the displacement of the variable hydraulic motor is adjusted through the opening control signal/displacement control signal to further change the flow passing through the proportional throttle valve or the variable hydraulic motor, the oil pressure at the outlet of the pump station is kept constant at all times, and finally constant pressure control of the outlet of the pump station is achieved. The pump station hydraulic pump set can generate pressure mutation in the processes of loading and unloading in sequence, and the pipeline can slowly rise or slowly fall by controlling the opening of the proportional throttle valve or the discharge capacity of the variable hydraulic motor, so that the pressure impact is reduced.
The hydraulic support 13 is specifically a hydraulic actuator in a coal mining hydraulic system.
When one hydraulic pump set is loaded or unloaded each time, the pressure detected by the pressure sensor 10 is fed back to the opening of the proportional throttle valve or the variable hydraulic motor for quick response adjustment, so that the oil pressure of an outlet pipeline of a pump station is kept constant all the time.
The constant voltage control method of the present invention, as shown in fig. 2, has the following control principle and process:
the pump station comprises a plurality of hydraulic pump sets which are connected in parallel, and each hydraulic pump set is provided with a motor, a hydraulic pump, a filter and an overflow valve; the output shaft of the motor is connected with the input shaft of the hydraulic pump, the oil inlet end of the hydraulic pump is communicated with the oil tank 9 through the filter, and the output end of the hydraulic pump is communicated with the oil tank 9 through the overflow valve. For example, the first electric motor 1 of the first hydraulic pump group drives the first hydraulic pump 2 to rotate, so that oil is pumped out of the oil tank 9 through the filter 3.
According to the specific implementation, three hydraulic pump sets are arranged, and a plurality of hydraulic pump sets are sequentially loaded or unloaded according to the required outlet pressure of a pump station.
The first hydraulic pump 2 of the first hydraulic pump group, the second hydraulic pump 5 of the second hydraulic pump group and the third hydraulic pump 7 of the third hydraulic pump group are sequentially loaded or unloaded, and the loading or unloading of the first hydraulic pump 2, the second hydraulic pump 5 and the third hydraulic pump 7 is respectively controlled by the first overflow valve 4, the second overflow valve 6 and the third overflow valve 8. If the expected pressure at the outlet of the pump station is smaller than P1, P1 represents the preset overflow pressure of the first overflow valve 4, at the moment, the first hydraulic pump 2 is loaded, and the second hydraulic pump 5 and the third hydraulic pump 7 are unloaded; when the expected pressure at the outlet of the pump station is greater than P1 and less than P2, P2 represents the preset overflow pressure of the second overflow valve 6, the first hydraulic pump 2 and the second hydraulic pump 5 are loaded, and the third hydraulic pump 7 is unloaded.
When one hydraulic pump group is loaded or unloaded each time, the pressure at the outlet of the pump station fluctuates suddenly, so that the oil pressure input to the electro-hydraulic valve group 12 is unstable, and the speed and position control of the hydraulic support 13 is seriously influenced.
When one hydraulic pump set is loaded or unloaded each time, the pressure sensor 10 of the outlet pipeline of the pump station detects the current pipeline pressure, and then the current pipeline pressure is fed back to the proportional throttle valve or the variable hydraulic motor 11 to react quickly, the displacement is adjusted to adjust the flow, and the flow is increased or decreased, so that the oil pressure of the outlet pipeline of the pump station is kept constant pressure all the time, or slowly rises or slowly falls.
The pressure change of the pipe can be represented by the following formula:
wherein B is the volume modulus of the oil,
is the amount of pressure change，q 1 For the flow at the input end of the pipeline, q 2 The output end of the pipeline is the input end flow of the electromagnetic valve group. q. q.s 3 In order to reduce the proportional throttle opening or the output flow of the displacement of the variable displacement hydraulic motor, V is the volume of a pipeline and is expressed as follows:
V＝πr 2 L
where r is the pipe radius.
For example, the preset pressures of the first relief valve 4, the second relief valve 6, and the third relief valve 8 are 15, 10, and 5mpa, respectively. When the input end flow of the electromagnetic valve group becomes large, the pressure sensor 10 detects the current pipeline pressure, the expected pressure is 9Mpa, the first overflow valve 4 and the second overflow valve 6 are always in a non-overflow state, the third overflow valve 8 is switched to the non-overflow state from the overflow state, and the differential pressure signal
And the pressure is continuously increased until the pressure is maintained at 11Mpa by outputting a control signal to the PID controller, and increasing the proportional throttle opening or the displacement of the variable hydraulic motor to increase the output flow of the proportional throttle opening or the variable hydraulic motor.
When the flow of the input end of the solenoid valve group becomes small, the pressure sensor 10 detects the current pipeline pressure, and when the expected pressure is 11Mpa, the expected pressure is 9Mpa, the first overflow valve 4 and the second overflow valve 6 are always in a non-overflow state, and the third overflow valve 8 is switched to an overflow state from the non-overflow state. The PID controller outputs a control signal to reduce the proportional throttle opening or the displacement of the variable hydraulic motor so as to reduce the output flow of the proportional throttle opening or the variable hydraulic motor, thereby reducing the pressure until the pressure is maintained at 9MPa.
Fig. 3 and 4 illustrate an embodiment of the present invention. The outlet of the pump station is connected with a proportional throttle valve 14 in parallel, a PID controller converts the pressure difference between the expected pressure and the current pipeline pressure into the opening of the proportional throttle valve, and the flow passing through the proportional throttle valve is adjusted to realize the constant pressure control of the pressure.
Fig. 5 and 6 illustrate another embodiment of the present invention. The outlet of the pump station is connected with a variable hydraulic motor 15 in parallel, the PID controller converts the pressure difference between the expected pressure and the current pipeline pressure into the displacement of the variable hydraulic motor, and the flow passing through the variable hydraulic motor is adjusted to realize the constant pressure control of the pressure.
The foregoing detailed description is intended to be illustrative of the invention, which is only one, but not all embodiments of the invention. Any modifications and variations of the present invention, which are within the spirit of the present invention and the scope of the appended claims, are within the scope of the present invention.
Claims (4)
1. A constant pressure control method of a pump station is characterized in that: a proportional throttle valve or a variable hydraulic motor is connected in parallel between an outlet of the pump station and an oil tank, one end of the proportional throttle valve or the variable hydraulic motor (11) is connected with an outlet pipeline of the pump station, and the other end of the proportional throttle valve or the variable hydraulic motor is connected with the oil tank; a pressure sensor (10) is arranged on an outlet pipeline of the pump station, the pressure sensor (10) is used for detecting the pressure of the outlet pipeline of the pump station and feeding the pressure back to the controller, and the controller outputs a proportional throttle valve opening control signal or a variable hydraulic motor displacement signal to realize the control of the proportional throttle valve or the variable hydraulic motor;
the pump station comprises a plurality of hydraulic pump sets which are connected in parallel, and the plurality of hydraulic pump sets are sequentially loaded and unloaded;
obtaining the expected pressure of an outlet of a pump station according to the position and speed requirements of the hydraulic support; the method comprises the steps that the current pipeline pressure is detected through a pressure sensor arranged on an outlet pipeline of a pump station, the expected pressure is compared with the current pipeline pressure to obtain a pressure difference, the pressure difference is input into a controller, the pressure difference is converted into an opening control signal of a proportional throttle valve or a displacement control signal of a variable hydraulic motor through the controller, the opening of the proportional throttle valve or the displacement of the variable hydraulic motor is adjusted by the opening control signal/the displacement control signal to further change the flow flowing through the proportional throttle valve or the variable hydraulic motor, the oil pressure at the outlet of the pump station is kept constant all the time, and finally the constant pressure control of the outlet of the pump station is achieved.
2. The constant pressure control method of the pump station according to claim 1, wherein:
the outlet end of the pump station is connected to the inlet end of the electro-hydraulic valve group (12), and the outlet end of the electro-hydraulic valve group (12) is output to the hydraulic support (13).
3. The constant pressure control method of the pump station according to claim 1, wherein:
the hydraulic support (13) is a hydraulic actuator in a coal mining hydraulic system.
4. The constant pressure control method of the pump station according to claim 1, wherein:
when one hydraulic pump set is loaded or unloaded each time, the pressure detected by the pressure sensor (10) is fed back to the opening of the proportional throttle valve or the variable hydraulic motor for quick response adjustment, so that the oil pressure of an outlet pipeline of the pump station is kept constant all the time.
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| CN202110829868.2A CN113757197B (en) | 2021-07-22 | 2021-07-22 | Constant pressure control method of pump station |
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| CN202110829868.2A CN113757197B (en) | 2021-07-22 | 2021-07-22 | Constant pressure control method of pump station |
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| CN114720087A (en) * | 2022-03-22 | 2022-07-08 | 山东核电设备制造有限公司 | Real current testing device and method for high-voltage throttling device for nuclear power |
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| CN110307193A (en) * | 2019-07-09 | 2019-10-08 | 中国矿业大学 | A kind of large-capacity valve-pump jointly controls emulsion power pack and its control method |
| CN110529463A (en) * | 2019-07-24 | 2019-12-03 | 徐州工程学院 | A kind of flexible hydraulic throttling speed control circuit experimental system |
| CN110836202A (en) * | 2019-12-05 | 2020-02-25 | 浙江大学 | Hydraulic source load self-adaptive system and self-adaptive control method thereof |
| CN111458067A (en) * | 2020-04-27 | 2020-07-28 | 太原矿机电气股份有限公司 | Movement detection device and detection method for monorail crane |
-
2021
- 2021-07-22 CN CN202110829868.2A patent/CN113757197B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0990802A2 (en) * | 1998-09-30 | 2000-04-05 | Robert Bosch Gmbh | Electrohydraulic speed control device for an hydraulic lifting cylinder |
| CN102720710A (en) * | 2012-06-26 | 2012-10-10 | 中联重科股份有限公司 | Hydraulic system, method for controlling hydraulic system and engineering machinery |
| CN105157974A (en) * | 2015-09-10 | 2015-12-16 | 福州大学 | High pressure bulk flow cartridge inserted valve test system based on LabVIEW and realization method |
| CN106768903A (en) * | 2015-11-23 | 2017-05-31 | 郭洪 | A kind of the valve for roof support testing stand |
| CN110307193A (en) * | 2019-07-09 | 2019-10-08 | 中国矿业大学 | A kind of large-capacity valve-pump jointly controls emulsion power pack and its control method |
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