CN112859946B

CN112859946B - Pressure overall control system for calibration platform and control method thereof

Info

Publication number: CN112859946B
Application number: CN202110052195.4A
Authority: CN
Inventors: 张茹; 谢和平; 李怡航; 高明忠; 陈领; 张泽天; 张志龙; 杨阳; 李佳南; 黄伟; 任利
Original assignee: Sichuan University
Current assignee: Sichuan University
Priority date: 2021-01-15
Filing date: 2021-01-15
Publication date: 2022-06-17
Anticipated expiration: 2041-01-15
Also published as: CN112859946A

Abstract

The invention provides a pressure integral control system for a calibration platform and a control method thereof, wherein the pressure integral control system comprises a main control computer, a bottom oil cylinder positioned at the bottom of a simulation cabin sample, and an osmotic pressure control module, a pore pressure control module and a confining pressure control module which are respectively connected with the main control computer; and a first high-pressure servo thrust oil source is arranged in the bottom oil cylinder. The invention comprises pore pressure, confining pressure and osmotic pressure control, and the combination of the pore pressure, the confining pressure and the osmotic pressure can heat and insulate the simulation cabin body, the liquid and the sample in the simulation cabin body, and apply corresponding pressure at the same time to restore the high-temperature and high-pressure environment in the deep in-situ environment, thereby providing a reliable temperature and pressure control system for the simulation cabin.

Description

Pressure overall control system for calibration platform and control method thereof

Technical Field

The invention belongs to the technical field of osmotic pressure control, and particularly relates to a pressure overall control system for a calibration platform and a control method thereof.

Background

Advancing to the deep part of the earth is an important direction of scientific and technological innovation in China in the near term and in the future. At present, mineral resources in the shallow part of the earth are gradually exhausted, resource development continuously moves to the deep part of the earth, the coal mining depth reaches 1500m, the geothermal mining depth exceeds 3000m, the metal mining depth exceeds 4350m, the oil and gas resource mining depth reaches 7500m, and deep resource mining becomes a normal state. The deep rock characteristics are proved, powerful support is provided for deep marching, the deep environment must be restored in a laboratory before deep in-situ fidelity coring work of actual engineering, and the reliability of a coring system is tested. The existing temperature and pressure control device for the reduction in-situ environment experiment basically stays in a shallow rock mechanics experiment stage, even a normal temperature and pressure stage; meanwhile, the condition of stress-temperature-osmotic pressure three-field coupling is rarely considered, and a core drilling or mechanical experiment may be started when each point in the sample is not uniform, so that large deviation is caused, the in-situ environment of the rock cannot be correctly restored, and the obtained experimental conclusion or the taken core has errors with the actual condition.

In a deep ground environment, the most obvious difference from a shallow part is the environment of a high-temperature high-pressure pipeline, the temperature and pressure environment can reach 100 ℃ and more than 100MPa, and in order to research deep in-situ coring, various properties under the deep in-situ temperature and pressure condition must be known. In some simulated coring or in-situ experiments, a temperature and pressure loading path is very important, particularly in a temperature and pressure environment of 100+ DEG C and 100+ MPa in deep ground, if the temperature and pressure loading path is inconsistent, water body gasification can be caused, and great disturbance is caused to the whole experiment system.

Disclosure of Invention

In view of the above-mentioned deficiencies in the prior art, the present invention provides an overall pressure control system for a calibration platform and a control method thereof, which can keep the temperature and pressure applying process stable while ensuring that the phase change of the fluid does not occur in the temperature and pressure applying process, and prevent the temperature and pressure environment from exceeding the single control limit due to the temperature and pressure coupling effect.

In order to achieve the above purpose, the invention adopts the technical scheme that:

the scheme provides a permeability control system applied to a simulation cabin, which comprises a main control computer, a bottom oil cylinder positioned at the bottom of a simulation cabin sample, and a permeability control module, a pore pressure control module and a confining pressure control module which are respectively connected with the main control computer; a first high-pressure servo thrust oil source is arranged in the bottom oil cylinder;

the main control computer is used for respectively sending alternate operation instructions to the osmotic pressure control module, the pore pressure control module and the confining pressure control module, and monitoring according to the instructions to obtain osmotic pressure information, pore pressure information and confining pressure information of the simulation cabin;

the osmotic pressure control module is used for monitoring osmotic pressure information of the simulation cabin according to an instruction sent by the main control computer;

the confining pressure control module is used for monitoring confining pressure information of the simulation cabin according to an instruction sent by the main control computer, and is positioned at the lower part of a sample of the simulation cabin;

the pore pressure control module is used for monitoring the pore pressure information of the simulation cabin according to an instruction sent by the main control computer;

and the bottom oil cylinder is used for providing thrust for the confining pressure control module.

Further, the osmotic pressure control module comprises a first flow controller, a first isolator and a first PLC controller; the first flow controller is connected with a main control computer through a first PLC controller, and the first isolator is connected with the first flow controller; the inlets and the outlets of the first flow controller and the first isolator are respectively provided with a first hydraulic control one-way valve and a first pressure monitoring unit; a first silt filtering unit and a cooling control unit are arranged at an outlet of the first isolator; a temperature acquisition module is arranged at the cooling control unit, and the main control computer, the first flow controller, the first isolator, the first PLC controller, the first hydraulic control one-way valve and the first pressure monitoring unit are in closed-loop control;

the pore pressure control module comprises a second flow controller, a second isolator, a second PLC controller, a first energy accumulator and a second sediment filtering unit positioned at the outlet of the second isolator; the second flow controller is connected with a main control computer through a second PLC controller, and the second isolator is connected with the second flow controller; the inlets and outlets of the second flow controller and the second isolator are respectively provided with a second hydraulic control one-way valve and a second pressure monitoring unit; the main control computer, the second flow controller, the second PLC, the second isolator, the second hydraulic control one-way valve and the second pressure monitoring unit are in closed-loop control;

the confining pressure control module comprises a third PLC controller and a hydraulic pump, the hydraulic pump is connected with an external oil tank and is connected to one end P of a first pipeline in the electromagnetic directional valve and the input end of an overflow valve, the output end of the overflow valve is connected to the oil tank, the other end A of the first pipeline in the electromagnetic directional valve is respectively connected with a liquid inlet of a third hydraulic control one-way valve, one end of a pipeline of a booster directional valve and a liquid inlet of a fourth hydraulic control one-way valve, a liquid outlet of the fourth hydraulic control one-way valve is connected to a bottom oil cylinder, a second energy accumulator and a pressure measuring instrument are arranged on a connecting pipeline of the fourth hydraulic control one-way valve and the bottom oil cylinder, a liquid outlet of the third hydraulic control one-way valve is respectively connected with a liquid inlet of a fifth hydraulic control one-way valve and the top of a booster cylinder, the bottom of the booster cylinder is connected with the other end of the pipeline of the booster directional valve, and the middle part of the booster cylinder is connected with a valve core of the booster directional valve and a liquid inlet of the sixth one-way valve, the liquid outlet of the sixth hydraulic control one-way valve is connected with one end B of a second pipeline in the electromagnetic directional valve, the other end T of the second pipeline in the electromagnetic directional valve is connected to an external oil tank, the liquid outlet of the fifth hydraulic control one-way valve is connected to the bottom oil cylinder, the third PLC is connected with the main control computer, and the third PLC is respectively connected with the main control computer, the hydraulic pump, the electromagnetic directional valve and the booster directional valve.

Still further, first flow controller and second flow controller's structure is the same, all includes servo thrust oil source of second superhigh pressure and the servo thrust oil source of third superhigh pressure, first hydraulic control check valve, first pressure monitoring unit, second hydraulic control check valve and second pressure monitoring unit are equallyd divide and are located respectively the business turn over mouth department of the servo thrust oil source of second superhigh pressure and the servo thrust oil source of third superhigh pressure, just the servo thrust oil source of second superhigh pressure and the servo thrust oil source of third superhigh pressure are equallyd divide and are connected with first isolator and second isolator respectively.

Still further, the temperature acquisition module comprises a temperature sensing circuit, an amplifying circuit connected with the temperature sensing circuit and a control circuit connected with the amplifying circuit, and the control circuit is connected with a main control computer through a USB.

Still further, the temperature sensing circuit adopts a sensing chip U1 with a Pt100 platinum resistor model, a 1 st pin and a 2 nd pin of the chip U1 are respectively connected with the amplifying circuit, and a 3 rd pin of the chip U1 is grounded;

the amplifying circuit comprises an operational amplifying chip U2, wherein a non-inverting input end of a chip U1 is connected with one ends of a grounding resistor R1 and a resistor R2 respectively, the other end of a resistor R2 is connected with a 1 st pin of a chip U1, an inverting input end of the chip U2 is connected with one end of a resistor R4 and one end of a resistor R3 respectively, the other end of a resistor R3 is connected with a 2 nd pin of the chip U1, the other end of the resistor R4 is connected with an output end of a chip U2 and one end of a resistor R5 respectively, the other end of a resistor R5 is used as an output end of the chip U2 and is connected with an I/O pin of a control circuit, a grounding end of the chip U2 is grounded, and a 1 st pin of the chip U2 is connected with a power supply and a grounding capacitor C1 respectively.

Still further, the first pressure monitoring unit, the second pressure monitoring unit and the pressure measuring instrument have the same structure and respectively comprise a pressure sensor U4, an AD conversion module, a single chip microcomputer module, a display module and a wireless communication module;

the pressure sensor is connected with the AD conversion module, and the single chip microcomputer module is respectively connected with the AD conversion module, the display module and the wireless communication module; the pressure sensor U3 is in a PTH702H model, and the 1 st pin of the pressure sensor U3 is connected with a +24V voltage;

the AD conversion module comprises an AD conversion chip U4 with the model number of TCL549CD, a REF + pin and a VCC pin of the AD conversion chip U4 are both connected with +5V voltage, a REF-pin and a GND pin of the AD conversion chip U4 are grounded, and an ANLGIN pin of the AD conversion chip U4 is connected with a 3 rd pin of a pressure sensor U3;

the single-chip microcomputer module comprises a single-chip microcomputer U5 with the model number of AT89S51, an XTAL1 pin of the single-chip microcomputer U5 is respectively connected with one end of a crystal oscillator X1 and a grounding capacitor C2, an XTAL2 pin of the single-chip microcomputer U5 is respectively connected with the crystal oscillator X1 and the grounding capacitor C3, an RST pin of the single-chip microcomputer U5 is respectively connected with one end of a resistor R1, a grounding capacitor C1 and a grounding switch K1, the other end of the resistor R1 is adjacent to +5V voltage, a P1.0 pin of the single-chip microcomputer U5 is connected with a CLK pin of an AD conversion chip U4, a P1.1 pin of the single-chip microcomputer U5 is connected with a DO pin of the AD conversion chip U4, and a P1.2 pin of the single-chip U5 is connected with a CS pin of the AD conversion chip U4;

the display module comprises a display screen LCD1 with a model number of LM1602, a VSS pin of a display screen LCD1 is connected with +5V voltage, a VDD pin of the display screen LCD1 is grounded, a VEE pin of the display screen LCD1 is connected with a sliding end of a sliding resistor RV1, a first fixed end of the sliding resistor RV1 is grounded, a second fixed end of the sliding resistor RV1 is connected with +5V voltage, an RS pin, a RW pin and an E pin of the display screen LCD1 are correspondingly connected with a P2.0 pin, a P2.1 pin and a P2.2 pin of a singlechip U5, pins D0 to D7 of the display screen LCD1 are correspondingly connected with a pin 2 to a pin 9 of an RP exclusion 1, a pin 2 to a pin 9 of the exclusion RP1 are correspondingly connected with a pin P0.0 to a pin P0.7 of the singlechip U5, and a pin 1 of the RP1 is connected with a voltage +5V voltage;

the wireless communication module comprises a wireless communication integrated board U6 with the model of NRF24L01+, a CE pin, a CSN pin, an SCK pin, an MOSI pin, a MISO pin and an IRQ pin of the wireless communication integrated board U6 are respectively connected with P3.0 to P3.5 of the single chip microcomputer U5 in a one-to-one correspondence mode, a VCC pin of the wireless communication integrated board U6 is connected with +3.3V voltage, and a GND pin of the wireless communication integrated board U6 is grounded.

Based on the system, the invention also provides a pressure overall control method for the calibration platform, which comprises the following steps:

s1, sending an alternate operation instruction to the osmotic pressure control module by using the main control computer, and monitoring osmotic pressure information of the simulation cabin;

s2, sending an alternate operation instruction to the pore pressure control module by using a main control computer, and monitoring the pore pressure information of the simulation cabin;

s3, sending an alternate operation instruction to the confining pressure control module by using a main control computer, and monitoring the confining pressure information of the simulation cabin;

s4, transmitting the osmotic pressure information, the confining pressure information and the pore pressure information obtained by monitoring to a main control computer;

and S5, finishing the pressure integral control of the calibration platform according to the instruction of stopping alternate operation sent by the main control computer.

Further, the step S1 includes the following steps:

s101, sending an alternate operation instruction to a second ultrahigh pressure servo thrust oil source and a third ultrahigh pressure servo thrust oil source by a main control computer through a first PLC (programmable logic controller);

s102, alternately pushing the first isolator by using a second ultrahigh pressure servo thrust oil source or a third ultrahigh pressure servo thrust oil source according to the instruction, and simultaneously respectively opening first hydraulic control one-way valves at the second ultrahigh pressure servo thrust oil source, the third ultrahigh pressure servo thrust oil source and an inlet of the first isolator;

s103, filtering liquid at the outlet of the first isolator by using a sediment filtering unit, and controlling the temperature of the discharged liquid to be lower than a preset temperature value by using a cooling control unit, wherein the preset temperature value is 60 ℃;

s104, monitoring osmotic pressure information at an inlet and an outlet of a second ultrahigh pressure servo thrust oil source or a third ultrahigh pressure servo thrust oil source by using a first pressure monitoring unit, and monitoring osmotic pressure information of the first isolator during alternate operation;

s105, transmitting the osmotic pressure information obtained by monitoring to a main control computer;

and S106, sending an instruction for stopping alternate operation to the second ultrahigh-pressure servo thrust oil source and the third ultrahigh-pressure servo thrust oil source through the main control computer, closing the first hydraulic control one-way valve, and completing monitoring of the osmotic pressure of the simulation cabin.

Still further, the step S2 includes the steps of:

s201, sending an alternate operation instruction to a second ultrahigh pressure servo thrust oil source and a third ultrahigh pressure servo thrust oil source by a main control computer through a second PLC controller;

s202, alternately pushing a second isolator by using a second ultrahigh pressure servo thrust oil source or a third ultrahigh pressure servo thrust oil source according to the instruction, and simultaneously respectively opening second hydraulic control one-way valves at the second ultrahigh pressure servo thrust oil source, the third ultrahigh pressure servo thrust oil source and the inlet of the second isolator;

s203, monitoring pore pressure information at an inlet and an outlet of the first ultrahigh pressure servo thrust oil source or the second ultrahigh pressure servo thrust oil source by using a second pressure monitoring unit, monitoring pore pressure information of the second isolator in alternate operation by using the second pressure monitoring unit, and filtering liquid by using a second silt filtering device;

s204, sending the monitored pore pressure information to a main control computer;

and S205, sending an instruction of stopping alternate operation to the second ultrahigh-pressure servo thrust oil source and the third ultrahigh-pressure servo thrust oil source through the main control computer, closing the second hydraulic control one-way valve, and completing monitoring of the pore pressure of the simulation cabin.

Still further, the step S3 includes the steps of:

s301, placing the rock sample into the oil cylinder, sending an operation instruction by the main control computer through the third PLC, and enabling the conduction direction of the electromagnetic directional valve to be from the hydraulic pump to the fourth hydraulic control one-way valve and the initial conduction direction of the booster directional valve to be from the booster cylinder to the electromagnetic directional valve according to the instruction;

s302, controlling a hydraulic pump to work through a third PLC, pumping oil in an external oil tank to an electromagnetic directional valve, and enabling the oil to sequentially pass through a fourth hydraulic control one-way valve, a second energy accumulator and a pressure measuring instrument to reach a bottom oil cylinder;

s303, judging whether the fourth hydraulic control one-way valve is automatically closed, if so, entering the step S304, otherwise, continuously judging until the fourth hydraulic control one-way valve is automatically closed, and entering the step S304;

s304, pumping oil in an external oil tank to an electromagnetic directional valve, enabling the oil to enter a top piston HP in a pressure cylinder through a third hydraulic control one-way valve, and pushing the top piston HP and a bottom piston LP to the bottom of the pressure cylinder by utilizing thrust generated by a first high-pressure servo thrust oil source in a bottom oil cylinder;

s305, driving a valve core of a supercharger reversing valve to move downwards through oil to the supercharger reversing valve for reversing, enabling the oil to reach the bottom of a supercharging cylinder from an electromagnetic reversing valve, pushing a top piston HP and a bottom piston LP to move upwards, and outputting high-pressure oil;

s306, enabling the high-pressure oil to sequentially pass through the fifth hydraulic control one-way valve, the second energy accumulator and the pressure measuring instrument to reach the oil cylinder, and monitoring the confining pressure of the simulation cabin in real time through the pressure measuring instrument, wherein during confining pressure measurement, the second energy accumulator stores energy, and when the pressure measured by the pressure measuring instrument is smaller than a set threshold value, the energy of the second energy accumulator is released to ensure that the pressure cannot drop; and after the confining pressure measurement is finished, the hydraulic pump is closed, the conduction direction of the electromagnetic directional valve is from the fourth hydraulic control one-way valve to the hydraulic pump, the sixth hydraulic control one-way valve is conducted, residual oil in the system sequentially passes through the sixth hydraulic control one-way valve and the electromagnetic directional valve and flows back to an external oil tank, and the monitoring of the confining pressure information of the simulation cabin is finished.

The invention has the beneficial effects that:

(1) the invention comprises pore pressure, confining pressure and osmotic pressure control, and the combination of the pore pressure, the confining pressure and the osmotic pressure can heat and preserve the temperature of the cabin body, the liquid in the cabin body and the sample, and simultaneously apply corresponding pressure to restore the high-temperature and high-pressure environment in the deep in-situ environment.

(2) According to the invention, the pressure sensor, the sediment filtering module and the cooling control module are arranged in the pipeline, so that the safety of the high-pressure pipeline is ensured, the high-temperature liquid can be effectively prevented from being gasified, the temperature of the discharged liquid is effectively ensured to be lower than 60 ℃, no gas is generated, the safe operation of the system is ensured, and a reliable temperature and pressure control system is provided for the simulation cabin.

(3) The occurrence environment of the deep high-temperature high-pressure pipeline is accurately restored in the simulation cabin, temperature and pressure regulation and control are carried out through various sensors, and the high-temperature high-pressure pipeline experiment device is prevented from being damaged due to temperature difference.

(4) The hydraulic pump in the confining pressure control module can continuously generate high-pressure fluid to act on a sample to generate high pressure, so that the simulation of a deep in-situ high-pressure environment is realized.

Drawings

FIG. 1 is a schematic diagram of the system of the present invention.

Fig. 2 is a schematic diagram of a confining pressure control system in the embodiment.

Fig. 3 is a schematic diagram of a temperature sensing circuit in this embodiment.

Fig. 4 is a schematic diagram of an amplifying circuit in the present embodiment.

Fig. 5 is a schematic diagram of the pressure tester in this embodiment.

Fig. 6 is a circuit diagram of the pressure tester in this embodiment.

FIG. 7 is a flow chart of the method of the present invention.

Wherein, 1-a main control computer, 2-a bottom oil cylinder, 3-a first flow controller, 4-a first isolator, 5-a first PLC controller, 6-a first hydraulic control one-way valve, 7-a first pressure monitoring unit, 8-a first silt filtering unit, 9-a cooling control unit, 10-a second flow controller, 11-a second isolator, 12-a second PLC controller, 13-a second hydraulic control one-way valve, 14-a second pressure monitoring unit, 15-a hydraulic pump, 16-an electromagnetic directional valve, 17-an overflow valve, 18-a third hydraulic control one-way valve, 19-a supercharger directional valve, 20-a fourth hydraulic control one-way valve, 21-a second energy accumulator, 22-a pressure measuring instrument, 23-a fifth hydraulic control one-way valve and 24-a sixth hydraulic control one-way valve, 25-a first energy accumulator, 26-a second sediment filtering unit, 27-a third PLC controller, 28-a pressure cylinder and 29-a temperature acquisition module.

Detailed Description

The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.

In the embodiment of the invention, the calibration platform is a short name for a deep in-situ fidelity coring five-guarantee capability calibration platform, and the simulation cabin is a short name for a deep in-situ high-temperature high-pressure environment simulation cabin.

Example 1

As shown in fig. 1, the present invention provides a pressure overall control system for a calibration platform, which comprises a main control computer 1, a bottom oil cylinder 2 located at the bottom of a simulation cabin sample, and an osmotic pressure control module, a pore pressure control module and a confining pressure control module which are respectively connected with the main control computer 1; a first high-pressure servo thrust oil source is arranged in the bottom oil cylinder 1; the main control computer 1 is used for respectively sending alternate operation instructions to the osmotic pressure control module, the pore pressure control module and the confining pressure control module, and monitoring according to the instructions to obtain osmotic pressure information, pore pressure information and confining pressure information of the simulation cabin; the osmotic pressure control module is used for monitoring osmotic pressure information of the simulation cabin according to an instruction sent by the main control computer 1; the confining pressure control module is used for monitoring confining pressure information of the simulation cabin according to an instruction sent by the main control computer 1 and is positioned at the upper part of a sample of the simulation cabin; the pore pressure control module is used for monitoring the pore pressure information of the simulation cabin according to an instruction sent by the main control computer 1; and the bottom oil cylinder 2 is used for providing thrust for the confining pressure control module.

In this embodiment, the osmotic pressure control module includes a first flow controller 3, a first isolator 4, and a first PLC controller 5; the first flow controller 3 is connected with a main control computer 1 through a first PLC (programmable logic controller) 5, and the first isolator 4 is connected with the first flow controller 3; the inlets and outlets of the first flow controller 3 and the first isolator 4 are respectively provided with a first hydraulic control one-way valve 6 and a first pressure monitoring unit 7; a first silt filtering unit 8 and a cooling control unit 9 are arranged at the outlet of the first isolator 4; the cooling control unit 9 is provided with a temperature acquisition module 29, and the main control computer 1, the first flow controller 3, the first isolator 4, the first PLC controller 5, the first hydraulic control one-way valve 6 and the first pressure monitoring unit 7 are controlled in a closed loop mode.

In this embodiment, the pore pressure control module includes a second flow controller 10, a second isolator 11, a second PLC controller 12, a first energy accumulator 25, and a second silt filtering unit 26 located at an outlet of the second isolator 11; the second flow controller 10 is connected with the main control computer 1 through a second PLC 12, and the second isolator 11 is connected with the second flow controller 10; the inlets and outlets of the second flow controller 10 and the second isolator 11 are respectively provided with a second hydraulic control one-way valve 13 and a second pressure monitoring unit 14; the main control computer 1, the second flow controller 10, the second PLC 12, the second isolator 11, the second hydraulic control one-way valve 13 and the second pressure monitoring unit 14 are in closed-loop control.

In this embodiment, as shown in fig. 2, the confining pressure control module includes a third PLC controller 27 and a hydraulic pump 15, the hydraulic pump 15 is connected to an external oil tank, and is connected to one end P of a first pipeline in the electromagnetic directional valve 16 and an input end of an overflow valve 17, an output end of the overflow valve 17 is connected to the oil tank, another end a of the first pipeline in the electromagnetic directional valve 16 is respectively connected to a liquid inlet of a third pilot-controlled check valve 18, a pipeline end of a booster directional valve 19 and a liquid inlet of a fourth pilot-controlled check valve 20, a liquid outlet of the fourth pilot-controlled check valve 20 is connected to the bottom oil cylinder 2, a second accumulator 21 and a pressure measuring instrument 22 are arranged on a connection pipeline between the fourth pilot-controlled check valve 20 and the bottom oil cylinder 2, a liquid outlet of the third pilot-controlled check valve 18 is respectively connected to a liquid inlet of a fifth pilot-controlled check valve 23 and a top of a booster cylinder 28, a bottom of the booster cylinder 28 is connected to another pipeline end of the booster directional valve 19, the middle part of the booster cylinder 28 is connected to a valve core of the booster reversing valve 19 and a liquid inlet of the sixth hydraulic control one-way valve 24, a liquid outlet of the sixth hydraulic control one-way valve 24 is connected with one end B of a second pipeline in the electromagnetic reversing valve 16, the other end T of the second pipeline in the electromagnetic reversing valve 16 is connected to an external oil tank, a liquid outlet of the fifth hydraulic control one-way valve 23 is connected to the bottom oil cylinder 2, the third PLC 27 is connected with the main control computer 1, and the third PLC 27 is respectively connected with the main control computer 1, the hydraulic pump 15, the electromagnetic reversing valve 16 and the booster reversing valve 19.

In this embodiment, the first flow controller 3 and the second flow controller 10 have the same structure and each include a second ultrahigh-pressure servo thrust oil source and a third ultrahigh-pressure servo thrust oil source, the first hydraulic control check valve 6, the first pressure monitoring unit 7, the second hydraulic control check valve 13, and the second pressure monitoring unit 14 are equally located at the inlet and outlet of the second ultrahigh-pressure servo thrust oil source and the third ultrahigh-pressure servo thrust oil source, and the second ultrahigh-pressure servo thrust oil source and the third ultrahigh-pressure servo thrust oil source are equally connected to the first isolator 4 and the second isolator 11.

In this embodiment, as shown in fig. 3 to 4, the temperature acquisition module 29 includes a temperature sensing circuit, an amplifying circuit connected to the temperature sensing circuit, and a control circuit connected to the amplifying circuit, and the control circuit is connected to the main control computer 1 through a USB. The temperature sensing circuit adopts a sensing chip U1 with a Pt100 platinum resistor model, a 1 st pin and a 2 nd pin of the chip U1 are respectively connected with the amplifying circuit, and a 3 rd pin of the chip U1 is grounded; the amplifying circuit comprises an operational amplifying chip U2, wherein a non-inverting input end of a chip U1 is connected with one ends of a grounding resistor R1 and a resistor R2 respectively, the other end of a resistor R2 is connected with a 1 st pin of a chip U1, an inverting input end of the chip U2 is connected with one end of a resistor R4 and one end of a resistor R3 respectively, the other end of a resistor R3 is connected with a 2 nd pin of the chip U1, the other end of the resistor R4 is connected with an output end of a chip U2 and one end of a resistor R5 respectively, the other end of a resistor R5 is used as an output end of the chip U2 and is connected with an I/O pin of a control circuit, a grounding end of the chip U2 is grounded, and a 1 st pin of the chip U2 is connected with a power supply and a grounding capacitor C1 respectively.

In this embodiment, the temperature of the liquid cooled by the cooling control unit 9 is collected by the temperature collecting module 29 to ensure that the temperature of the discharged liquid is lower than a preset temperature value.

In this embodiment, an STM32F407ZGT6 based on an ARM Core-M4 Core is used as a main control chip of a controller, a PT100 platinum resistor temperature sensor is used, an amplification circuit is used to obtain an analog voltage value of the temperature in a pore pipeline, the analog voltage value is transmitted to an I/O pin of the controller, and the controller reads an analog voltage mean value and transmits the analog voltage mean value to a computer through a USB interface or an RS485 bus, so that the control of the pore temperature is realized.

In this embodiment, the controller circuit is a single chip microcomputer of the model STM32F407ZGT6, and the circuit structure thereof belongs to the prior art, and a person skilled in the art can configure itself based on the general knowledge of the basic electronic circuit and the content explained in this embodiment, and details thereof are not described herein.

In this embodiment, the Pt100 platinum resistance temperature sensor can eliminate errors caused by its own resistance, and ensure that the performance tends to be stable in a high-temperature environment. When the Pt100 platinum resistance temperature sensor is placed at a high ambient temperature, the change of the ambient temperature and the resistance value of the resistance are close to a linear relationship, in the embodiment, the Pt100 platinum resistance temperature sensor adopts a three-wire connection method, and a third lead wire in the three-wire connection method compensates for a precision error caused by the resistance of the lead wire.

In this embodiment, as shown in fig. 5 to 6, the first pressure monitoring unit 7, the second pressure monitoring unit 14 and the pressure measuring instrument 22 have the same structure, and each include a pressure sensor U4, an AD conversion module, a single chip microcomputer module, a display module and a wireless communication module; the pressure sensor is connected with the AD conversion module, and the single chip microcomputer module is respectively connected with the AD conversion module, the display module and the wireless communication module; the pressure sensor is connected with the AD conversion module, and the single chip microcomputer module is respectively connected with the AD conversion module, the display module and the wireless communication module; the pressure sensor U3 is in a PTH702H model, and the 1 st pin of the pressure sensor U3 is connected with a +24V voltage; the AD conversion module comprises an AD conversion chip U4 with the model number of TCL549CD, a REF + pin and a VCC pin of the AD conversion chip U4 are both connected with +5V voltage, a REF-pin and a GND pin of the AD conversion chip U4 are grounded, and an ANLGIN pin of the AD conversion chip U4 is connected with a 3 rd pin of a pressure sensor U3; the single-chip microcomputer module comprises a single-chip microcomputer U5 with the model number of AT89S51, an XTAL1 pin of the single-chip microcomputer U5 is respectively connected with one end of a crystal oscillator X1 and a grounding capacitor C2, an XTAL2 pin of the single-chip microcomputer U5 is respectively connected with the crystal oscillator X1 and the grounding capacitor C3, an RST pin of the single-chip microcomputer U5 is respectively connected with one end of a resistor R1, a grounding capacitor C1 and a grounding switch K1, the other end of the resistor R1 is adjacent to +5V voltage, a P1.0 pin of the single-chip microcomputer U5 is connected with a CLK pin of an AD conversion chip U4, a P1.1 pin of the single-chip microcomputer U5 is connected with a DO pin of the AD conversion chip U4, and a P1.2 pin of the single-chip U5 is connected with a CS pin of the AD conversion chip U4; the display module comprises a display screen LCD1 with a model LM1602, a VSS pin of the display screen LCD1 is connected with +5V voltage, a VDD pin of the display screen LCD1 is grounded, a VEE pin of the display screen LCD1 is connected with a sliding end of a sliding resistor RV1, a first fixed end of the sliding resistor RV1 is grounded, a second fixed end of the sliding resistor RV1 is connected with +5V voltage, an RS pin, a RW pin and an E pin of the display screen LCD1 are correspondingly connected with a P2.0 pin, a P2.1 pin and a P2.2 pin of a singlechip U5, pins D0 to D7 of the display screen LCD1 are correspondingly connected with a pin 2 to a pin 9 of an RP exclusion 1, a pin 2 to a pin 9 of the exclusion 1 are correspondingly connected with a pin P0.0 to a pin P0.7 of the singlechip U5, and a pin 1 of the RP1 is connected with +5V voltage; the wireless communication module comprises a wireless communication integrated board U6 with the model of NRF24L01+, a CE pin, a CSN pin, an SCK pin, an MOSI pin, a MISO pin and an IRQ pin of the wireless communication integrated board U6 are respectively connected with P3.0 to P3.5 of the single chip microcomputer U5 in a one-to-one correspondence mode, a VCC pin of the wireless communication integrated board U6 is connected with +3.3V voltage, and a GND pin of the wireless communication integrated board U6 is grounded.

In this embodiment, pressure sensor U4 measures pressure, obtains analog signal, and analog signal passes through AD conversion module and converts digital signal into, transmits digital signal to single chip module and handles, obtains the pressure value to pass through the display screen display with the pressure value and transmit to computer equipment through wireless communication module.

In the embodiment, the invention comprises 4 high-precision infinite flow thrust water sources (comprising a bottom oil cylinder), the rated pressure is 140MPa, the rated flow is 0-100ml/min in stepless speed regulation, the resolution is 0.01MPa, the stable precision is +/-0.3 percent F.S, and the double water sources are alternately used to achieve automatic infinite water supply; 3 PLC controllers, which ensure that each pressurized oil source can be controlled independently and work cooperatively; the silt filter can guarantee effectively that the impurity of the internal circulating fluid of the cabin body is below certain limit to guarantee the safe and stable work of each pump head, also guaranteed the life of each high-pressure pipeline simultaneously.

In this embodiment, the pressure sensor and the hydraulic control valve are connected to the computer and the PLC controller to cooperatively operate.

In this embodiment, the pore pressure control module uses a set of ultra-high pressure infinite volume flow controllers (composed of two ultra-high pressure servo thrust oil sources, referred to as "oil sources" for short) to control the oil sources to alternately operate, and pushes a set of ultra-high pressure infinite volume isolators (used for oil-water conversion, referred to as "isolators" for short). The separators are operated alternately, so that the osmotic water pressure and the flow can be kept and controlled to be continuously output. The oil inlet and outlet of each group of oil source or isolator are equipped with independent hydraulic control one-way valve and closed-loop control pressure and temperature sensor, and they are combined together with computer and PLC controller to form a large closed-loop control system. It is achieved that each set of pressurized oil sources (or isolators) can be controlled individually and in cooperation with each other. The stable, reliable and safe application of osmotic water pressure is realized.

In this embodiment, the osmotic pressure module operates on the same principle as the osmotic pressure module, and a group of oil sources alternately operates to push a group of isolators. Because at the sample exit end, be equipped with silt filter equipment for preventing that outflow liquid is thoughtlessly there is silt, add cooling control device for the high temperature liquid gasification that prevents to let out, guarantee that the discharge liquid temperature is less than being unlikely to produce gas below the 60 degrees, guarantee the safe operation of system.

In this embodiment, in order to ensure that the osmotic water pressure at the upper and lower ends of the sample is uniform, and verify whether the osmotic water pressure is balanced, a proper pore water inlet pressure should be applied at the osmotic water inlet, and after a counter pressure smaller than the water inlet pressure is applied at the upper part of the sample, the counter pressure is maintained for a period of time, and when the counter pressure at the outlet end of the osmotic water is substantially equal to the pressure of the water inlet pore at the bottom of the sample, the pore pressure in each area inside the sample can be considered to be uniform.

By installing the pressure sensor, the sediment filtering unit and the cooling control unit in the pipeline, the invention can effectively prevent the high-temperature liquid from being gasified while ensuring the safety of the high-pressure pipeline, can effectively ensure that the temperature of the discharged liquid is lower than 60 ℃ and no gas is generated, ensures the safe operation of the system, provides a reliable temperature and pressure control system for the deep in-situ fidelity coring simulation cabin, and can provide basic pre-research conditions for the exploration of deep in-situ rock mechanics and deep related subjects.

In this embodiment, can continuously produce high-pressure oil through confined pressure control module, send high-pressure oil into the hydro-cylinder in order to exert pressure to the rock specimen, simulate its high-pressure environment in underground, realized the confined pressure measurement to the rock specimen. After the confining pressure measurement is finished, residual oil in the pressurization system can flow back to the external oil tank.

In this embodiment, the whole system is composed of a whole set of large closed-loop control system composed of a main control computer, multiple sets of PLC controllers, corresponding pressure, flow and corresponding mechanical devices. The system is uniformly commanded by control software, the operation control work of the whole system is automatically completed, the safety control system always ensures that the monitoring is in place in the whole test process, and safety accidents are accurately prevented. The emergency accident seedling head can give an alarm in time in advance to remind an operator to intervene in inspection and carry out safety scheme operation, a manual emergency valve is arranged at the bottom oil cylinder, a pressure system can be manually closed at an emergency, and safety of equipment and personnel is guaranteed.

Example 2

As shown in fig. 7, the present invention further provides a pressure overall control method for calibrating a platform, which is implemented as follows:

s1, sending an alternate operation instruction to the osmotic pressure control module by using the main control computer, and monitoring osmotic pressure information of the simulation cabin, wherein the implementation method comprises the following steps:

s103, filtering the liquid at the outlet of the first isolator by using a sediment filtering unit, and controlling the temperature of the discharged liquid to be lower than a preset temperature value by using a cooling control unit, wherein the preset temperature value is 60 ℃;

s106, sending an instruction for stopping alternate operation to the second ultrahigh-pressure servo thrust oil source and the third ultrahigh-pressure servo thrust oil source through the main control computer, closing the first hydraulic control one-way valve, and completing monitoring of osmotic pressure of the simulation cabin;

s2, sending an alternate operation instruction to the pore pressure control module by using a main control computer, and monitoring the pore pressure information of the simulation cabin, wherein the realization method comprises the following steps:

s203, monitoring pore pressure information at an inlet and an outlet of the first ultrahigh pressure servo thrust oil source or the second ultrahigh pressure servo thrust oil source by using a second pressure monitoring unit, monitoring pore pressure information of the second isolator during alternate operation by using the second pressure monitoring unit, and filtering liquid by using a second sediment filtering device;

s205, sending an instruction of stopping alternate operation to the second ultrahigh-pressure servo thrust oil source and the third ultrahigh-pressure servo thrust oil source through a main control computer, closing a second hydraulic control one-way valve, and completing monitoring of the pore pressure of the simulation cabin;

s3, sending an alternate operation instruction to the confining pressure control module by using the main control computer, and monitoring the confining pressure information of the simulation cabin, wherein the implementation method comprises the following steps:

s302, controlling a hydraulic pump to work through a third PLC, pumping oil in an external oil tank to an electromagnetic directional valve, and enabling the oil to reach a bottom oil cylinder through a fourth hydraulic control one-way valve, a second energy accumulator and a pressure measuring instrument in sequence;

s306, enabling the high-pressure oil to sequentially pass through the fifth hydraulic control one-way valve, the second energy accumulator and the pressure measuring instrument to reach the oil cylinder, and monitoring the confining pressure of the simulation cabin in real time through the pressure measuring instrument, wherein during confining pressure measurement, the second energy accumulator is used for storing energy, and when the pressure measured by the pressure measuring instrument is smaller than a set threshold value, the energy of the second energy accumulator is released to ensure that the pressure cannot be reduced; after the confining pressure measurement is finished, the hydraulic pump is closed, the conduction direction of the electromagnetic directional valve is from the fourth hydraulic control one-way valve to the hydraulic pump, the sixth hydraulic control one-way valve is conducted, and residual oil in the system flows back to an external oil tank through the sixth hydraulic control one-way valve and the electromagnetic directional valve in sequence, so that the monitoring of the confining pressure information of the simulation cabin is finished;

In this embodiment, the main control computer, the PLC controller, the hydraulic control check valve, and the pressure monitoring unit are closed-loop control.

In this embodiment, the second ultrahigh pressure servo thrust oil source, the third ultrahigh pressure servo thrust oil source and the isolator can be controlled independently.

In this example, the osmotic pressure input is supplied from the bottom of the sample: a group of ultrahigh pressure infinite volume flow controllers (consisting of two ultrahigh pressure servo thrust oil sources, which are called as oil sources for short) are used for controlling the oil sources to alternately operate by a computer to push a group of ultrahigh pressure infinite volume isolators (used for oil-water conversion, which are called as isolators for short). The separators are operated alternately, so that the osmotic water pressure and the flow can be kept and controlled to be continuously output. The oil inlet and outlet of each group of oil source or isolator are equipped with independent hydraulic control one-way valve and closed-loop control pressure and temperature sensor, and they are combined together with computer and PLC controller to form a large closed-loop control system. It is achieved that each set of pressurized oil sources (or isolators) can be controlled individually and in cooperation with each other. The stable, reliable and safe application of osmotic water pressure is realized.

In this example, the permeate pressure outlet port was controlled at the top of the sample: the working principle is the same as the above, and a group of oil sources alternately operates to push a group of isolators. Because at the sample exit end, be equipped with silt filter equipment for preventing that outflow liquid is thoughtlessly there is silt, add cooling control device for the high temperature liquid gasification that prevents to let out, guarantee that the discharge liquid temperature is less than being unlikely to produce gas below the 60 degrees, guarantee the safe operation of system.

In this embodiment, in order to ensure that the osmotic water pressure at the upper and lower ends of the sample is uniform, and verify whether the osmotic water pressure is balanced, a proper pore water inlet pressure should be applied to the osmotic water inlet (bottom of the sample), and after a counter pressure smaller than the water inlet pressure is applied to the upper part of the sample, the counter pressure is maintained for a period of time, and when the counter pressure at the osmotic outlet end (top of the sample) is substantially equal to the water inlet pore pressure at the bottom of the sample, the pore pressure in each region inside the sample can be considered to be uniform.

According to the invention, the pressure sensor, the sediment filtering unit and the cooling control unit are arranged in the pipeline, so that the safety of the high-pressure pipeline is ensured, the high-temperature liquid discharged can be effectively prevented from being gasified, the temperature of the discharged liquid is effectively ensured to be lower than 60 ℃, no gas is generated, the safe operation of the system is ensured, a reliable temperature and pressure control system is provided for a simulation cabin, and a basic pre-research condition can be provided for the exploration of deep in-situ rock mechanics and deep related subjects.

In this embodiment, can continuously produce high-pressure oil through confining pressure control module, send high-pressure oil into the hydro-cylinder in order to exert pressure to the rock specimen, simulate its high-pressure environment in underground, realized the confining pressure measurement to the rock specimen. After the confining pressure measurement is finished, residual oil in the pressurization system can flow back to the external oil tank.

In the embodiment, the whole method is formed by a whole set of large closed-loop control system which is formed by one main control computer, a plurality of sets of PLC controllers, corresponding pressure, flow and corresponding mechanical equipment. The system is uniformly commanded by control software, the operation control work of the whole system is automatically completed, the safety control system always ensures that the monitoring is in place in the whole test process, the safety accident is accurately prevented, the safety accident can be timely and early alarmed when the safety accident occurs, the intervention inspection and the safety scheme operation of an operator are reminded, a manual emergency valve is configured at the bottom oil cylinder, the pressure system can be manually closed at the emergency moment, and the safety of equipment and personnel is ensured.

Claims

1. The pressure integral control system for the calibration platform is characterized by comprising a main control computer (1), a bottom oil cylinder (2) positioned at the bottom of a simulation cabin sample, and a permeation pressure control module, a pore pressure control module and a confining pressure control module which are respectively connected with the main control computer (1); a first high-pressure servo thrust oil source is arranged in the bottom oil cylinder (2);

the main control computer (1) is used for respectively sending alternate operation instructions to the osmotic pressure control module, the pore pressure control module and the confining pressure control module, and monitoring according to the instructions to obtain osmotic pressure information, pore pressure information and confining pressure information of the simulation cabin;

the osmotic pressure control module is used for monitoring osmotic pressure information of the simulation cabin according to an instruction sent by the main control computer (1);

the confining pressure control module is used for monitoring confining pressure information of the simulation cabin according to an instruction sent by the main control computer (1), and is positioned at the lower part of a sample of the simulation cabin;

the pore pressure control module is used for monitoring the pore pressure information of the simulation cabin according to an instruction sent by the main control computer (1);

the bottom oil cylinder (2) is used for providing thrust for the confining pressure control module;

the osmotic pressure control module comprises a first flow controller (3), a first isolator (4) and a first PLC (programmable logic controller) (5); the first flow controller (3) is connected with a main control computer (1) through a first PLC (5), and the first isolator (4) is connected with the first flow controller (3); the inlets and outlets of the first flow controller (3) and the first isolator (4) are respectively provided with a first hydraulic control one-way valve (6) and a first pressure monitoring unit (7); a first silt filtering unit (8) and a cooling control unit (9) are arranged at an outlet of the first isolator (4); a temperature acquisition module (29) is arranged at the cooling control unit (9), and the main control computer (1), the first flow controller (3), the first isolator (4), the first PLC (programmable logic controller) (5), the first hydraulic control one-way valve (6) and the first pressure monitoring unit (7) are in closed-loop control;

the pore pressure control module comprises a second flow controller (10), a second isolator (11), a second PLC (programmable logic controller) controller (12), a first energy storage device (25) and a second silt filtering unit (26) positioned at the outlet of the second isolator (11); the second flow controller (10) is connected with a main control computer (1) through a second PLC (12), and the second isolator (11) is connected with the second flow controller (10); the inlets and outlets of the second flow controller (10) and the second isolator (11) are provided with a second hydraulic control one-way valve (13) and a second pressure monitoring unit (14); the main control computer (1), the second flow controller (10), the second PLC (programmable logic controller) (12), the second isolator (11), the second hydraulic control one-way valve (13) and the second pressure monitoring unit (14) are in closed-loop control;

the confining pressure control module comprises a third PLC (programmable logic controller) (27) and a hydraulic pump (15), the hydraulic pump (15) is connected with an external oil tank and is connected to one end P of a first pipeline in an electromagnetic directional valve (16) and the input end of an overflow valve (17), the output end of the overflow valve (17) is connected to the external oil tank, the other end A of the first pipeline in the electromagnetic directional valve (16) is respectively connected with a liquid inlet of a third hydraulic control one-way valve (18), one end of a pipeline of a booster directional valve (19) and a liquid inlet of a fourth hydraulic control one-way valve (20), a liquid outlet of the fourth hydraulic control one-way valve (20) is connected to the bottom oil cylinder (2), a second energy accumulator (21) and a pressure measuring instrument (22) are arranged on a connecting pipeline of the fourth hydraulic control one-way valve (20) and the bottom oil cylinder (2), a liquid outlet of the third hydraulic control one-way valve (18) is respectively connected with a liquid inlet of a fifth hydraulic control one-way valve (23) and the top of a booster cylinder (28), the bottom of the pressure cylinder (28) is connected with the other end of the pipeline of the pressure booster reversing valve (19), the middle of the pressure cylinder (28) is connected to a valve core of the pressure booster reversing valve (19) and a liquid inlet of a sixth hydraulic control one-way valve (24), a liquid outlet of the sixth hydraulic control one-way valve (24) is connected with one end B of a second pipeline in the electromagnetic reversing valve (16), the other end T of the second pipeline in the electromagnetic reversing valve (16) is connected to an external oil tank, a liquid outlet of a fifth hydraulic control one-way valve (23) is connected to the bottom oil cylinder (2), a third PLC (27) is connected with the main control computer (1), and the third PLC (27) is respectively connected with the main control computer (1), the hydraulic pump (15), the electromagnetic reversing valve (16) and the pressure booster reversing valve (19);

the structure of first flow controller (3) and second flow controller (10) is the same, all includes servo thrust oil source of second superhigh pressure and the servo thrust oil source of third superhigh pressure, first hydraulic control check valve (6), first pressure monitoring unit (7), second hydraulic control check valve (13) and second pressure monitoring unit (14) are equallyd divide and are located respectively the business turn over mouth department of the servo thrust oil source of second superhigh pressure and the servo thrust oil source of third superhigh pressure, just the servo thrust oil source of second superhigh pressure and the servo thrust oil source of third superhigh pressure are equallyd divide and are connected with first isolator (4) and second isolator (11) respectively.

2. The pressure overall control system for the calibration platform according to claim 1, wherein the temperature acquisition module (29) comprises a temperature sensing circuit, an amplifying circuit connected with the temperature sensing circuit and a control circuit connected with the amplifying circuit, and the control circuit is connected with a main control computer (1) through a USB.

3. The pressure overall control system for the calibration platform as claimed in claim 2, wherein the temperature sensing circuit adopts a sensing chip U1 with a Pt100 platinum resistor model, the No. 1 pin and the No. 2 pin of the chip U1 are respectively connected with the amplifying circuit, and the No. 3 pin of the chip U1 is grounded;

the amplifying circuit comprises an operational amplifier chip U2, wherein the non-inverting input end of a chip U1 is connected with one ends of a grounding resistor R1 and a resistor R2 respectively, the other end of a resistor R2 is connected with the 1 st pin of the chip U1, the inverting input end of the chip U2 is connected with one end of a resistor R4 and one end of a resistor R3 respectively, the other end of the resistor R3 is connected with the 2 nd pin of the chip U1, the other end of the resistor R4 is connected with the output end of the chip U2 and one end of the resistor R5 respectively, the other end of the resistor R5 serves as the output end of the chip U2 and is connected with the I/O pin of the control circuit, the grounding end of the chip U2 is grounded, and the 1 st pin of the chip U2 is connected with a power supply and a grounding capacitor C1 respectively.

4. The pressure overall control system for the calibration platform according to claim 3, wherein the first pressure monitoring unit (7), the second pressure monitoring unit (14) and the pressure measuring instrument (22) have the same structure, and each of the first pressure monitoring unit, the second pressure monitoring unit and the pressure measuring instrument comprises a pressure sensor U4, an AD conversion module, a single chip microcomputer module, a display module and a wireless communication module;

the wireless communication module comprises a wireless communication integrated board U6 with the model of NRF24L01+, a CE pin, a CSN pin, an SCK pin, an MOSI pin, a MISO pin and an IRQ pin of the wireless communication integrated board U6 are respectively connected with P3.0 to P3.5 of a singlechip U5 in a one-to-one correspondence manner, a VCC pin of the wireless communication integrated board U6 is connected with +3.3V voltage, and a GND pin of the wireless communication integrated board U6 is grounded.

5. The pressure integral control method for the calibration platform is characterized by comprising the following steps of:

6. The pressure overall control method for the calibration platform according to claim 5, wherein the step S1 comprises the following steps:

7. The pressure overall control method for the calibration platform according to claim 5, wherein the step S2 comprises the following steps:

and S205, sending an instruction of stopping alternate operation to the second ultrahigh-pressure servo thrust oil source and the third ultrahigh-pressure servo thrust oil source through a main control computer, closing a second hydraulic control one-way valve, and completing monitoring of the pore pressure of the simulation cabin.

8. The pressure overall control method for the calibration platform according to claim 5, wherein the step S3 comprises the following steps:

s306, enabling the high-pressure oil to sequentially pass through the fifth hydraulic control one-way valve, the second energy accumulator and the pressure measuring instrument to reach the oil cylinder, and monitoring the confining pressure of the simulation cabin in real time through the pressure measuring instrument, wherein during confining pressure measurement, the second energy accumulator is used for storing energy, and when the pressure measured by the pressure measuring instrument is smaller than a set threshold value, the energy of the second energy accumulator is released to ensure that the pressure cannot be reduced; and after the confining pressure measurement is finished, the hydraulic pump is closed, the conduction direction of the electromagnetic directional valve is from the fourth hydraulic control one-way valve to the hydraulic pump, the sixth hydraulic control one-way valve is conducted, residual oil in the system sequentially flows back to the external oil tank through the sixth hydraulic control one-way valve and the electromagnetic directional valve, and the monitoring of the confining pressure information of the simulation cabin is finished.