CN113124019B - Digital logic valve array hydraulic servo control system, control method and fault diagnosis method - Google Patents

Digital logic valve array hydraulic servo control system, control method and fault diagnosis method Download PDF

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CN113124019B
CN113124019B CN202110486463.3A CN202110486463A CN113124019B CN 113124019 B CN113124019 B CN 113124019B CN 202110486463 A CN202110486463 A CN 202110486463A CN 113124019 B CN113124019 B CN 113124019B
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low
switch valve
valve
frequency sound
digital switch
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CN113124019A (en
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丘铭军
李向辉
陈国防
艾春璇
郭佳
雷丛卉
刘杰
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China National Heavy Machinery Research Institute Co Ltd
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China National Heavy Machinery Research Institute Co Ltd
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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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/02—Servomotor systems with programme control derived from a store or timing device; Control devices therefor
    • 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
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • 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
    • F15B15/1423—Component parts; Constructional details
    • 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
    • F15B15/1423—Component parts; Constructional details
    • F15B15/1447—Pistons; Piston to piston rod assemblies
    • F15B15/1452—Piston sealings
    • 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
    • F15B15/1423—Component parts; Constructional details
    • F15B15/1471—Guiding means other than in the end cap
    • 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
    • F15B15/20—Other details, e.g. assembly with regulating devices
    • F15B15/28—Means for indicating the position, e.g. end of stroke
    • F15B15/2815—Position sensing, i.e. means for continuous measurement of position, e.g. LVDT
    • 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
    • F15B19/005—Fault detection or monitoring
    • 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
    • F15B20/00—Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
    • F15B20/005—Leakage; Spillage; Hose burst
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/04—Special measures taken in connection with the properties of the fluid
    • F15B21/041—Removal or measurement of solid or liquid contamination, e.g. filtering
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/715—Output members, e.g. hydraulic motors or cylinders or control therefor having braking means
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/86—Control during or prevention of abnormal conditions
    • F15B2211/863—Control during or prevention of abnormal conditions the abnormal condition being a hydraulic or pneumatic failure
    • F15B2211/8636—Circuit failure, e.g. valve or hose failure
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/87—Detection of failures
    • 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
    • F15B2215/00—Fluid-actuated devices for displacing a member from one position to another
    • F15B2215/30—Constructional details thereof

Abstract

The invention relates to a digital logic valve array hydraulic servo control system, a control method and a fault self-diagnosis method, which are used for accurately controlling a hydraulic cylinder. The hydraulic position servo intelligent control system has the advantages of high efficiency, energy conservation, good stability, low failure rate, low price, digital signal control by direct connection with a computer, quick braking function of the hydraulic cylinder under the accident state, high reliability of equipment, state monitoring, automatic fault diagnosis and other functions, and is easy to realize hydraulic position servo intelligent control.

Description

Digital logic valve array hydraulic servo control system, control method and fault diagnosis method
Technical Field
The invention relates to the technical field of hydraulic position control, in particular to a digital logic valve array hydraulic servo control system, a control method and a fault self-diagnosis method.
Background
The on-line heat width adjusting technology is to change the width of a casting blank by controlling the position of the narrow side of a crystallizer, such as the Chinese patent authorization publication number: the CN105757065B structure provides an online maintaining hydraulic servo control system for mold taper, which can detect the current position (real-time position) of a hydraulic cylinder by a displacement sensor according to the mold taper set by the process, and compare the current position with a theoretical value by a comparator. When the actual value deviates from the theoretical value, the comparator controls the servo valve, and the hydraulic cylinder is controlled by the servo valve to realize the online position control function of the taper of the crystallizer required by the given taper signal.
The servo valve control technology can control displacement and force very accurately, but the servo valve has the defects of high price, high requirement on use environment, high requirement on oil cleanliness (higher than NAS6 level), high difficulty in analyzing and processing faults and the like, and control signals are analog quantities which are easy to interfere. Moreover, because the servo valve for width thermal adjustment of the crystallizer works under the severe working conditions of high temperature, high humidity, high dust and high pollution, the system has low reliability, the position of the narrow edge of the crystallizer is easy to change abnormally, high-temperature molten steel is leaked, major equipment and personnel safety production accidents are caused, and the safety production and the operation rate of a continuous casting machine are influenced.
The servo control of the position is as the Chinese patent authorization publication number: the CN107725509B structure is an agile position control system and method based on a high-speed switch valve air pressure balance regulation strategy, the high-frequency response rapid action of the high-speed switch valve is adopted to realize the accurate position control of the system, the method can overcome partial problems caused by adopting a servo valve, the reliability of the system is effectively improved, but because the high-speed switch valve is expensive, and the high-frequency action of the valve core easily causes the fatigue damage of the valve core and the valve seat, the system and the method have few successful application cases in industrial engineering.
Disclosure of Invention
In order to overcome the defects in the prior art, the invention aims to provide a digital logic valve array hydraulic servo control system, a control method and a fault self-diagnosis method, which are particularly used in the technical field of online thermal width modulation of continuous casting crystallizers, have the advantages of high efficiency, energy conservation, good stability, low fault rate and low price, can be directly connected with a computer to realize digital signal control, can quickly realize the braking function of a hydraulic cylinder in an accident state, ensure high operation rate of continuous casting production, and simultaneously have the functions of state monitoring, fault automatic diagnosis and the like.
In order to achieve the purpose, the invention adopts the following technical scheme:
a hydraulic servo control system of a digital logic valve array is used for on-line thermal width adjustment of a continuous casting crystallizer and comprises a leakage alarm loop 43, a low-frequency response control loop 44, a hydraulic cylinder 14, a displacement sensor 15 and an electric controller 19; the oil port P of the leakage alarm loop 43 is connected with the oil port P of the low frequency response control loop 44, and the oil port T of the leakage alarm loop 43 is connected with the oil port T of the low frequency response control loop 44; an oil port A of the low-frequency response control loop 44 is connected with an oil port 42 of a piston cavity of the hydraulic cylinder 14; an oil port B of the low-frequency response control loop 44 is connected with an oil port 41 of a piston rod cavity of the hydraulic cylinder 14; the oil port P1 of the low frequency response control loop 44 is connected with the brake oil port 40 of the hydraulic cylinder 14; the compressed air CA is connected to the cooling air port CA of the low frequency response control circuit 44 and the compressed air passage 37 of the hydraulic cylinder 14, respectively;
the leakage alarm loop 43 consists of a filter (11), a ball valve (13), a relay (20), a first one-way valve (401), a third throttle valve (203), a second one-way valve (402) and an electromagnetic valve (12); the main pressure pipeline P0 of the leakage alarm circuit 43 is connected with the oil port a of the relay 20, the oil port a of the first check valve 401 and the oil port a of the third throttle valve 203 through the filter 11, and the oil port P of the electromagnetic valve 12 is connected with the oil port B of the relay 20, the oil port B of the first check valve 401 and the oil port B of the third throttle valve 203; an oil port B of the electromagnetic valve 12 is connected with an oil port P of the leakage alarm loop 43; the main oil return pipeline T0 of the leakage alarm loop 43 is connected with the oil port T of the solenoid valve 12 and the oil port T of the leakage alarm loop 43 through the oil port B of the second check valve 402 and the oil port a respectively; the main pressure line P0 of the leakage warning circuit 43 is connected to the main return line T0 via a ball valve 13;
the low-frequency response control loop 44 consists of a first hydraulic control one-way valve 801, a second hydraulic control one-way valve 802, an overflow valve 10, a sequence valve 27, a third one-way valve 403 and a low-frequency response digital intelligent valve 7; an oil port A of the low-frequency response digital intelligent valve 7 is connected with an oil port 42 of a piston cavity of the hydraulic cylinder 14 through an oil port A of the first hydraulic control one-way valve 801 and an oil port B; an oil port B of the low-frequency response digital intelligent valve 7 is connected with an oil port 41 of a piston rod cavity of the hydraulic cylinder 14 through an oil port A of the second hydraulic control one-way valve 802 and the oil port B; a control oil port X of the first hydraulic control one-way valve 801 and a control oil port X of the second hydraulic control one-way valve 802 are respectively connected with an oil port P of the low frequency response control loop 44, and an oil drainage port Y of the first hydraulic control one-way valve 801 and an oil drainage port Y of the second hydraulic control one-way valve 802 are respectively connected with an oil port T of the low frequency response control loop 44; the oil port P of the low-frequency response control loop 44 is connected with the oil port P1 of the low-frequency response control loop 44 through the oil port B from the oil port A of the one-way throttle valve 21; an oil port A of the low-frequency response control loop 44 is connected with an oil port T of the low-frequency response control loop 44 through an oil port P of the overflow valve 10 through the oil port T; the oil port B of the low frequency response control loop 44 is connected with the oil port a of the low frequency response control loop 44 through the oil port P of the sequence valve 27 via the oil port T, and the oil port B of the low frequency response control loop 44 is connected with the oil port T of the low frequency response control loop 44 via the oil port B of the third check valve 403 via the oil port a;
the low-frequency-response digital intelligent valve 7 consists of a first low-frequency-response flow pulse digital switch valve 101, a second low-frequency-response flow pulse digital switch valve 102, a third low-frequency-response flow pulse digital switch valve 103, a fourth low-frequency-response flow pulse digital switch valve 104, a first pressure sensor 601, a second pressure sensor 602, a third pressure sensor 603 and a fourth pressure sensor 604; an oil port P of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port P of a first low-frequency sound flow pulse digital switch valve 101 and an oil port P of a third low-frequency sound flow pulse digital switch valve 103, an oil port T of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port P of a fourth low-frequency sound flow pulse digital switch valve 104 and an oil port A of a second low-frequency sound flow pulse digital switch valve 102, an oil port A of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port A of the first low-frequency sound flow pulse digital switch valve 101 and an oil port A of the fourth low-frequency sound flow pulse digital switch valve 104, and an oil port B of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port A of the third low-frequency sound flow pulse digital switch valve 103 and an oil port P of the second low-frequency sound flow pulse digital switch valve 102; a first pressure sensor 601 is arranged at an oil port P of the low-frequency-response digital intelligent valve 7, a second pressure sensor 602 is arranged at an oil port T of the low-frequency-response digital intelligent valve 7, a third pressure sensor 603 is arranged at an oil port A of the low-frequency-response digital intelligent valve 7, and a fourth pressure sensor 604 is arranged at an oil port B of the low-frequency-response digital intelligent valve 7;
the hydraulic cylinder 14 comprises a cylinder body 45, a piston 46, a piston rod 49, a front flange 24, a braking device 22 and a front end cover 31; the piston 46 separates the cylinder body 45 into a piston cavity and a piston rod cavity, a guide ring 47 and a sealing ring 48 are arranged on the piston, and the piston 46 and a piston rod 49 are of an integral structure; the front flange 24 is connected with the cylinder body 45 through threads, and the front end cover 31 fixes the braking device 22 on the front flange 24 through a bolt 34 and an elastic pad 33; the brake device 22 is provided with three sets of first guide belts 501, a main seal 25, a first auxiliary seal 301 and a static seal 23, and the brake device 22 is provided with a brake release oil path 40 and a compressed air path 37; the loop 26 is provided with two sets of second secondary seals 302, two sets of third secondary seals 303 and two sets of second guide belts 502; the first brake sleeve 901 and the second brake sleeve 902 are uniformly distributed on the inner circumferential inclined plane of the loop 26, and a tin bronze material 28 is welded on the inner circumferential sides of the first brake sleeve 901 and the second brake sleeve 902 in a stacking mode; one end of the loop 26 is provided with six pairs of pre-compression belleville springs 29; the front end cover 31 is provided with a static seal 23, three sets of first guide belts 501, a dust ring 32, a cooling air passage 36 and a cooling purging groove 35; a displacement sensor 15 is arranged on the hydraulic cylinder 14;
the electric controller 19 is composed of a comparator 18, a digital regulator 16, and a changeover switch 17; the digital regulator 16 is respectively connected with a first low-frequency sound flow pulse digital switch valve 101, a second low-frequency sound flow pulse digital switch valve 102, a third low-frequency sound flow pulse digital switch valve 103 and a fourth low-frequency sound flow pulse digital switch valve 104 through cables; the change-over switch 17 is connected with the electromagnetic valve 12 through a cable; the comparator 18 is connected with the displacement sensor 15, the relay 20, the first pressure sensor 601, the second pressure sensor 602, the third pressure sensor 603, the fourth pressure sensor 604, the first low-frequency volume impulse digital switch valve 101 monitor S, the second low-frequency volume impulse digital switch valve 102 monitor S, the third low-frequency volume impulse digital switch valve 103 monitor S and the fourth low-frequency volume impulse digital switch valve 104 monitor S through cables.
The change-over switch 17 of the electric controller 19 generates a signal 0, and the electromagnet of the electromagnetic valve 12 has no current; oil liquid in a pressure cavity 39 of the braking device 22 flows through an oil port P1 of the low frequency response control circuit 44 through a braking oil port 40 and then is connected with an oil port P of the low frequency response control circuit 44 through an oil port B of the one-way throttle valve 21 and an oil port A, the precompression force of the belleville spring 29 of the braking device 22 overcomes the hydraulic system return pressure value T' of the pressure cavity 39 of the braking device 22, the loop 26 moves leftwards, the first braking sleeve 901 and the second braking sleeve 902 can move towards the axis of the piston rod 49 under the action of the inner circumferential inclined surface of the loop 26, so that the surfacing welding tin-copper material 28 reliably brakes the piston rod 49, and the quick braking of the piston rod 49 of the hydraulic cylinder 14 is realized.
The low-frequency response digital intelligent valve 7 is used for controlling the position of the hydraulic cylinder 14, the first dampers 201 are arranged on oil ports A of the first low-frequency response flow pulse digital switch valve 101 and the fourth low-frequency response flow pulse digital switch valve 104, the second dampers 202 are arranged on oil ports A of the second low-frequency response flow pulse digital switch valve 102 and the third low-frequency response flow pulse digital switch valve 103, and the position of the hydraulic cylinder 14 can be accurately controlled by detecting the real-time position of the hydraulic cylinder 14 through the displacement sensor 15; the first low-frequency sound flow pulse digital switch valve 101, the second low-frequency sound flow pulse digital switch valve 102, the third low-frequency sound flow pulse digital switch valve 103 and the fourth low-frequency sound flow pulse digital switch valve 104 are cone valve type or ball valve type switch valves.
The first pressure sensor 601 is used for detecting the pressure value of an oil port P of the low-frequency response digital intelligent valve 7, the second pressure sensor 602 is used for detecting the pressure value of an oil port T of the low-frequency response digital intelligent valve 7, the third pressure sensor 603 is respectively used for detecting the pressure values of an oil port A of the low-frequency response digital intelligent valve 7 and a piston cavity of the hydraulic cylinder 14, and the fourth pressure sensor 604 is respectively used for detecting the pressure values of an oil port B of the low-frequency response digital intelligent valve 7 and a piston rod cavity of the hydraulic cylinder 14.
The first brake sleeve 901 and the second brake sleeve 902 are uniformly distributed on the inner circumferential inclined plane of the loop 26, and the pretightening force of six pairs of pre-compressed belleville springs 29 arranged at one end of the loop 26 enables the tin bronze material 28 welded on the inner circumferential sides of the first brake sleeve 901 and the second brake sleeve 902 to brake the piston rod 49; the six pre-compressed belleville springs 29 make pairs of two plates that reduce the axial distance of the brake 22.
The compressed air CA realizes the cooling function of the hydraulic components in the low-frequency-response control loop 44; the compressed air CA enters the cooling air passage 36 from the compressed air passage 37 and then is discharged through the cooling purging groove 35, so that external dirt is prevented from entering the hydraulic cylinder 14 from the dust ring 32, the hydraulic cylinder 14 is prevented from being damaged, and the reliability of the system and the high-reliability operation of the hydraulic cylinder 14 are improved.
The control method of the hydraulic servo control system of the digital logic valve array,
when the system works, the change-over switch 17 of the electric controller 19 generates a signal +1, and the electromagnet of the electromagnetic valve 12 is electrified; a pressure value P' of the hydraulic system enters a braking oil port 40 of the braking device 22 through the one-way throttle valve 21 and acts on the pressure chamber 39 to overcome the precompression force of the belleville spring 29 so as to realize that the loop 26 moves rightwards, so that the first braking sleeve 901 and the second braking sleeve 902 can reversely move towards the axis of the piston rod 49 under the action of the inner circumferential inclined surface of the loop 26, the braking release of the piston rod 49 of the hydraulic cylinder 14 is realized, and the piston rod 49 can freely move; the digital regulator 16 of the electric controller 19 controls the first low-frequency sound flow rate pulse digital switch valve 101, the second low-frequency sound flow rate pulse digital switch valve 102, the third low-frequency sound flow rate pulse digital switch valve 103 and the fourth low-frequency sound flow rate pulse digital switch valve 104 in pairs, that is, the digital regulator 16 controls the electromagnets of the first low-frequency sound flow rate pulse digital switch valve 101 and the second low-frequency sound flow rate pulse digital switch valve 102 at the same time, or the digital regulator 16 controls the electromagnets of the third low-frequency sound flow rate pulse digital switch valve 103 and the fourth low-frequency sound flow rate pulse digital switch valve 104 at the same time; according to the position deviation of the hydraulic cylinder 14 measured by the displacement sensor 15, when the hydraulic cylinder 14 extends and is controlled, the digital regulator 16 generates a signal +1, and the electromagnet of the first low-frequency sound flow pulse digital switch valve 101 is electrified; at the same time, the digital regulator 16 generates a signal-1, and the electromagnet of the second low-frequency sound flow pulse digital switch valve 102 is electrified; extension control of hydraulic cylinder 14 is achieved; or according to the position deviation of the hydraulic cylinder 14 measured by the displacement sensor 15, when the hydraulic cylinder 14 is controlled to retract, the digital regulator 16 generates a signal +1, and the electromagnet of the third low-frequency sound flow pulse digital switch valve 103 is electrified; at the same time, the digital regulator 16 generates a signal-1, and the electromagnet of the fourth low-frequency sound flow pulse digital switch valve 104 is electrified; retraction control of hydraulic cylinder 14 is effected; according to the extending and retracting functions of the hydraulic cylinder 14, high-precision position control of the hydraulic cylinder 14 is realized, so that the position of the hydraulic cylinder 14 required by the process is ensured, meanwhile, when the position value of the hydraulic cylinder 14 measured by the displacement sensor 15 is within the range value required by the process, the first low-frequency response flow pulse digital switch valve 101, the second low-frequency response flow pulse digital switch valve 102, the third low-frequency response flow pulse digital switch valve 103 and the fourth low-frequency response flow pulse digital switch valve 104 are powered off, the oil path consisting of the first low-frequency response flow pulse digital switch valve 101, the second low-frequency response flow pulse digital switch valve 102, the third low-frequency response flow pulse digital switch valve 103 and the fourth low-frequency response flow pulse digital switch valve 104 has no leakage stopping function in the positive and negative direction, and the extending and retracting actions of the hydraulic cylinder 14 are triggered until the position value of the displacement sensor 15 exceeds the range value required by the process due to tiny leakage of hydraulic components and the hydraulic cylinder 14, thereby realizing the function of reducing energy consumption;
the hydraulic cylinder 14 can realize a speed stepless regulation function and is realized by regulating the duty ratio PWM of a first low-frequency sound flow pulse digital switch valve 101, a second low-frequency sound flow pulse digital switch valve 102, a third low-frequency sound flow pulse digital switch valve 103 and a fourth low-frequency sound flow pulse digital switch valve 104;
when the set value of the electric controller 19 is required to control the hydraulic cylinder 14 to perform constant-speed or variable-speed extending motion, the flow-pressure difference equation is used
Figure GDA0003380837650000061
In a clear view of the above, it is known that,the duty ratio PWM of the first low-frequency sound flow pulse digital switch valve 101 is automatically controlled by detecting the pressure difference at two ends of the first low-frequency sound flow pulse digital switch valve 101, namely, the difference value between the first pressure sensor 601 and the third pressure sensor 603 is detected, so that the flow passing through the first low-frequency sound flow pulse digital switch valve 101 is automatically controlled, the speed of the hydraulic cylinder 14 is intelligently controlled, and the second low-frequency sound flow pulse digital switch valve 102 is in a fully open state at the moment, the return oil throttling loss of a hydraulic servo system is reduced by the logic array control technology of the low-frequency sound flow pulse digital switch valve, and the technical problem of serious oil heating caused by the coupling control of the valve core of the servo valve in an oil feeding and returning way is avoided; similarly, the set value of electrical controller 19, when required to control the constant or variable-speed retraction of hydraulic cylinder 14, is based on the flow-pressure differential equation
Figure GDA0003380837650000062
It can be known that by detecting the pressure difference between the two ends of the third low-frequency volume-ringing digital pulse switching valve 103, that is, detecting the difference between the fourth pressure sensor 604 and the second pressure sensor 602, the duty ratio PWM of the third low-frequency volume-ringing digital pulse switching valve 103 is automatically controlled, the flow passing through the third low-frequency volume-ringing digital pulse switching valve 103 is automatically controlled, so as to intelligently control the speed of the hydraulic cylinder 14, and at this time, the fourth low-frequency volume-ringing digital pulse switching valve 104 is in a fully open state; wherein: in the flow-pressure difference equation, CdIs the flow coefficient, ω is the area gradient of the valve, xvFor spool displacement, ρ is oil density, PsSupply pressure to the system, PLIs the load pressure.
8. A method of fault self-diagnosis of a hydraulic servo control system of a digital logic valve array as claimed in any one of claims 1 to 6, wherein:
according to the flow-pressure difference equation
Figure GDA0003380837650000063
It can be seen that the set values of the electric controller 19 are set to the first low-frequency-response-flow-rate pulse digital on-off valve 101, the second low-frequency-response-flow-rate pulse digital on-off valve 102, and the third low-frequency response flowThe hydraulic component with the fault is automatically judged by detecting the numerical values of the first pressure sensor 601, the second pressure sensor 602, the third pressure sensor 603, the fourth pressure sensor 604 and the displacement sensor 15 according to a certain duty ratio PWM of the volume pulse digital switch valve 103 and the fourth low-frequency volume pulse digital switch valve 104;
the specific method comprises the following steps: the first low-frequency sound flow pulse digital switch valve 101 is electrified, the monitor S of the first low-frequency sound flow pulse digital switch valve 101 is in a working position, and meanwhile, the measured value of the third pressure sensor 603 is the pressure value P' of the hydraulic system, so that the first low-frequency sound flow pulse digital switch valve 101 works normally; if the first low-frequency-response flow pulse digital switch valve 101 is electrified, but the monitor S of the first low-frequency-response flow pulse digital switch valve 101 is in a non-working position, the first low-frequency-response flow pulse digital switch valve 101 is in a fault; if the first low-frequency volume pulse digital switch valve 101 is de-energized, but the monitor S of the first low-frequency volume pulse digital switch valve 101 is at the working position, and the third pressure sensor 603 is the pressure value P' of the hydraulic system, the first low-frequency volume pulse digital switch valve 101 fails;
if the third low-frequency sound flow pulse digital switch valve 103 is electrified, the monitor S of the third low-frequency sound flow pulse digital switch valve 103 is at the working position, and the measurement value of the fourth pressure sensor 604 is the pressure value P' of the hydraulic system, the third low-frequency sound flow pulse digital switch valve 103 works normally; if the third low-frequency-response flow pulse digital switch valve 103 is electrified, but the monitor S of the third low-frequency-response flow pulse digital switch valve 103 is in a non-working position, the third low-frequency-response flow pulse digital switch valve 103 is in a fault; if the third low-frequency volume pulse digital switch valve 103 is de-energized, but the monitor S of the third low-frequency volume pulse digital switch valve 103 is at the working position, and the fourth pressure sensor 604 is at the pressure value P' of the hydraulic system, the third low-frequency volume pulse digital switch valve 103 fails;
if the first low-frequency sound flow pulse digital switch valve 101 and the fourth low-frequency sound flow pulse digital switch valve 104 are both powered, the monitor S of the fourth low-frequency sound flow pulse digital switch valve 104 is at a working position, and the measurement value of the third pressure sensor 603 is the hydraulic system return oil pressure value T', the first low-frequency sound flow pulse digital switch valve 101 works normally; if the first low-frequency response flow digital pulse switch valve 101 and the fourth low-frequency response flow digital pulse switch valve 104 are both powered, but the monitor S of the fourth low-frequency response flow digital pulse switch valve 104 is in a non-working position, and the third pressure sensor 603 is a pressure value P' of the hydraulic system, the fourth low-frequency response flow digital pulse switch valve 104 fails; if the first low-frequency sound flow pulse digital switch valve 101 is electrified and the fourth low-frequency sound flow pulse digital switch valve 104 is not electrified, but the monitor S of the fourth low-frequency sound flow pulse digital switch valve 104 is at a working position and the third pressure sensor 603 is a hydraulic system return oil pressure value T', the fourth low-frequency sound flow pulse digital switch valve 104 fails;
if the third low-frequency sound flow digital pulse switch valve 103 and the second low-frequency sound flow digital pulse switch valve 102 are both powered, the monitor S of the second low-frequency sound flow digital pulse switch valve 102 is at a working position, and the measurement value of the fourth pressure sensor 604 is the hydraulic system return oil pressure value T', the second low-frequency sound flow digital pulse switch valve 102 works normally; if the third low-frequency sound flow pulse digital switch valve 103 and the second low-frequency sound flow pulse digital switch valve 102 are both electrified, but the monitor S of the second low-frequency sound flow pulse digital switch valve 102 is in a non-working position, the second low-frequency sound flow pulse digital switch valve 102 breaks down; if the third low-frequency volume impulse digital switch valve 10 is powered on and the second low-frequency volume impulse digital switch valve 102 is powered off, but the monitor S of the second low-frequency volume impulse digital switch valve 102 is at the working position, and the fourth pressure sensor 604 is the hydraulic system return pressure value T', the second low-frequency volume impulse digital switch valve 102 has a fault.
According to the fault self-diagnosis method, the signal +1 is generated by the change-over switch 17 of the electric controller 19, the electromagnet of the electromagnetic valve 12 is electrified, the relay 20 of the leakage alarm loop 43 sends a signal to indicate that oil passes through the first one-way valve 401 due to leakage of an external pipeline, so that the relay 20 acts, and at the moment, the electric controller 19 automatically controls the electromagnet of the electromagnetic valve 12 to be powered off to prompt that a leakage accident state occurs in the system.
Compared with the prior art, the invention has the following advantages:
the invention is easy to realize the accurate control of the hydraulic cylinder, has the advantages of high efficiency, energy saving, good stability, low failure rate and low cost, and can be directly connected with a computer to realize the digital signal control; meanwhile, the quick braking function of the hydraulic cylinder can be realized in an accident state, and the high reliability of the equipment is guaranteed; moreover, the system also has the functions of state monitoring, automatic fault diagnosis and the like, and can realize the intelligent control of the hydraulic position servo.
Drawings
Fig. 1 is a schematic diagram of a digital logic valve array hydraulic servo control system, a control method and a fault self-diagnosis method.
Detailed Description
The following is an embodiment of the invention, the details of which are given by way of description of the embodiment and accompanying fig. 1.
As shown in fig. 1, the hydraulic servo control system of a digital logic valve array according to the present invention is used in the field of on-line thermal width modulation technology for continuous casting crystallizers, and has the following specific structure:
the invention consists of a leakage alarm loop 43, a low-frequency response control loop 44, a hydraulic cylinder 14, a displacement sensor 15 and an electric controller 19. The oil port P of the leakage alarm loop 43 is connected with the oil port P of the low frequency response control loop 44, and the oil port T of the leakage alarm loop 43 is connected with the oil port T of the low frequency response control loop 44; an oil port A of the low-frequency response control loop 44 is connected with an oil port 42 of a piston cavity of the hydraulic cylinder 14; an oil port B of the low-frequency response control loop 44 is connected with an oil port 41 of a piston rod cavity of the hydraulic cylinder 14; the oil port P1 of the low frequency response control loop 44 is connected with the brake oil port 40 of the hydraulic cylinder 14; the compressed air CA is connected to the cooling port CA of the low-frequency-response control circuit 44 and the compressed air passage 37 of the hydraulic cylinder 14, respectively.
The leakage alarm loop 43 is composed of a filter 11, a ball valve 13, a relay 20, a first one-way valve 401, a third throttle valve 203, a second one-way valve 402 and an electromagnetic valve 12; the main pressure pipeline P0 of the leakage alarm circuit 43 is connected with the oil port a of the relay 20, the oil port a of the first check valve 401 and the oil port a of the third throttle valve 203 through the filter 11, and the oil port P of the electromagnetic valve 12 is connected with the oil port B of the relay 20, the oil port B of the first check valve 401 and the oil port B of the third throttle valve 203; an oil port B of the electromagnetic valve 12 is connected with an oil port P of the leakage alarm loop 43; the main oil return pipeline T0 of the leakage alarm loop 43 is connected with the oil port T of the solenoid valve 12 and the oil port T of the leakage alarm loop 43 through the oil port B of the second check valve 402 and the oil port a respectively; the main pressure line P0 of the leakage warning circuit 43 is connected to the main return line T0 via a ball valve 13.
The low-frequency response control loop 44 consists of a first hydraulic control one-way valve 801, a second hydraulic control one-way valve 802, an overflow valve 10, a sequence valve 27, a third one-way valve 403 and a low-frequency response digital intelligent valve 7; an oil port A of the low-frequency response digital intelligent valve 7 is connected with an oil port 42 of a piston cavity of the hydraulic cylinder 14 through an oil port A of the first hydraulic control one-way valve 801 and an oil port B; an oil port B of the low-frequency response digital intelligent valve 7 is connected with an oil port 41 of a piston rod cavity of the hydraulic cylinder 14 through an oil port A of the second hydraulic control one-way valve 802 and the oil port B; a control oil port X of the first hydraulic control one-way valve 801 and a control oil port X of the second hydraulic control one-way valve 802 are respectively connected with an oil port P of the low frequency response control loop 44, and an oil drainage port Y of the first hydraulic control one-way valve 801 and an oil drainage port Y of the second hydraulic control one-way valve 802 are respectively connected with an oil port T of the low frequency response control loop 44; the port P of the low frequency response control circuit 44 is connected to the port P1 of the low frequency response control circuit 44 through the port B from the port a of the check throttle valve 21. An oil port A of the low-frequency response control loop 44 is connected with an oil port T of the low-frequency response control loop 44 through an oil port P of the overflow valve 10 through the oil port T; the oil port B of the low frequency response control circuit 44 is connected to the oil port a of the low frequency response control circuit 44 through the oil port P of the sequence valve 27 via the oil port T, and the oil port B of the low frequency response control circuit 44 is connected to the oil port T of the low frequency response control circuit 44 through the oil port B of the third check valve 403 via the oil port a.
The low-frequency-response digital intelligent valve 7 consists of a first low-frequency-response flow pulse digital switch valve 101, a second low-frequency-response flow pulse digital switch valve 102, a third low-frequency-response flow pulse digital switch valve 103, a fourth low-frequency-response flow pulse digital switch valve 104, a first damper 201, a second damper 202, a first pressure sensor 601, a second pressure sensor 602, a third pressure sensor 603 and a fourth pressure sensor 604; an oil port P of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port P of a first low-frequency sound flow digital pulse switch valve 101 and an oil port P of a third low-frequency sound flow digital pulse switch valve 103, an oil port T of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port T of a fourth low-frequency sound flow digital pulse switch valve 104 and an oil port T of a second low-frequency sound flow digital pulse switch valve 102, the oil port A of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port A of the first low-frequency sound flow digital pulse switch valve 101 and an oil port A of the fourth low-frequency sound flow digital pulse switch valve 104 through a first damper 201, and an oil port B of the low-frequency sound digital intelligent valve 7 is respectively connected with an oil port A of the third low-frequency sound flow digital pulse switch valve 103 and an oil port A of the second low-frequency sound flow digital pulse switch valve 102 through a second damper 202; an oil port P of the low-frequency-response digital intelligent valve 7 is provided with a first pressure sensor 601, an oil port T of the low-frequency-response digital intelligent valve 7 is provided with a second pressure sensor 602, an oil port A of the low-frequency-response digital intelligent valve 7 is provided with a third pressure sensor 603, and an oil port B of the low-frequency-response digital intelligent valve 7 is provided with a fourth pressure sensor 604.
The first damper 201 is arranged on the oil ports a of the first low-frequency response flow digital pulse switch valve 101 and the fourth low-frequency response flow digital pulse switch valve 104, the second damper 202 is arranged on the oil ports a of the second low-frequency response flow digital pulse switch valve 102 and the third low-frequency response flow digital pulse switch valve 103, and the position of the hydraulic cylinder 14 can be accurately controlled by detecting the real-time position of the hydraulic cylinder 14 through the displacement sensor 15.
The hydraulic cylinder 14 includes a cylinder 45, a piston 46, a piston rod 49, a front flange 24, a stopper 22, and a front cover 31. The piston 46 separates the cylinder body 45 into a piston cavity and a piston rod cavity, a guide ring 47 and a sealing ring 48 are arranged on the piston, and the piston 46 and a piston rod 49 are of an integral structure; the front flange 24 is connected with the cylinder body 45 through threads, and the front end cover 31 fixes the braking device 22 on the front flange 24 through a bolt 34 and an elastic pad 33; the brake device 22 is provided with three sets of first guide belts 501, a main seal 25, a first auxiliary seal 301 and a static seal 23, and the brake device 22 is provided with a brake release oil path 40 and a compressed air path 37; the loop 26 is provided with two sets of second secondary seals 302, two sets of third secondary seals 303 and two sets of second guide belts 502; the first brake sleeve 901 and the second brake sleeve 902 are uniformly distributed on the inner circumferential inclined plane of the loop 26, and a tin bronze material 28 is welded on the inner circumferential sides of the first brake sleeve 901 and the second brake sleeve 902 in a stacking mode; one end of the loop 26 is provided with six pairs of pre-compression belleville springs 29; the front end cover 31 is provided with a static seal 23, three sets of first guide belts 501, a dust ring 32, a cooling air passage 36 and a cooling purging groove 35; the hydraulic cylinder 14 is provided with a displacement sensor 15.
The electrical controller 19 is composed of a comparator 18, a digital regulator 16, and a changeover switch 17. The digital regulator 16 is respectively connected with a first low-frequency-response flow pulse digital switch valve 101, a second low-frequency-response flow pulse digital switch valve 102, a third low-frequency-response flow pulse digital switch valve 103 and a fourth low-frequency-response flow pulse digital switch valve 104 through cables; the change-over switch 17 is connected with the electromagnetic valve 12 through a cable; the comparator 18 is connected with the displacement sensor 15, the relay 20, the first pressure sensor 601, the second pressure sensor 602, the third pressure sensor 603, the fourth pressure sensor 604, the first low-frequency volume impulse digital switch valve 101 monitor S, the second low-frequency volume impulse digital switch valve 102 monitor S, the third low-frequency volume impulse digital switch valve 103 monitor S and the fourth low-frequency volume impulse digital switch valve 104 monitor S through cables.
The filter 11 is used for filtering oil, and because the crystallizer often needs offline maintenance, the dismantlement of pipeline leads to the foul to get into the hydraulic system pipeline easily, sets up filter 11 and prevents that rear portion hydraulic component from leading to appearing the jam phenomenon because the filth gets into the pipeline and leading to hydraulic component trouble.
The second check valve 402 is used for preventing oil in the main oil return line from entering the control system, so that the position of the hydraulic cylinder 14 is changed; the third check valve 403 is used for oil compensation of the piston rod cavity of the hydraulic cylinder 14, so as to prevent the piston rod cavity of the hydraulic cylinder 14 from generating a suction phenomenon, which results in damage to the seal of the hydraulic cylinder 14.
The ball valve 13 is used for flushing and decompressing pipelines, a crystallizer which is newly used in an online process is flushed by opening the ball valve 13, and dirt is prevented from entering a rear pipeline; meanwhile, when the pipeline is disassembled, the residual pressure in the pipeline can be released by opening the ball valve 13, so that the pipeline is disassembled simply and safely; the ball valve 13 is normally closed during production.
The electromagnetic directional valve 12 is used for cutting off a high-pressure oil source in a shutdown or accident state and controlling the first hydraulic control one-way valve 801 and the second hydraulic control one-way valve 802 to be opened and closed.
The low-frequency response digital intelligent valve 7 is used for position closed-loop automatic control of the hydraulic cylinder 14, wherein the first low-frequency response flow pulse digital switch valve 101, the second low-frequency response flow pulse digital switch valve 102, the third low-frequency response flow pulse digital switch valve 103 and the fourth low-frequency response flow pulse digital switch valve 104 are cone valve type or ball valve type switch valves, and have a complete cut-off function and high pollution resistance.
The first hydraulic control check valve 801 and the second hydraulic control check valve 802 are used for locking the position of the hydraulic cylinder 14 in the hydraulic cylinder accident state.
The overflow valve 10 is used for pressure protection of a piston cavity of the hydraulic cylinder 14, and damage to sealing of the hydraulic cylinder 14 caused by overhigh pressure is prevented.
Sequence valve 27 is used for overpressure protection of the piston rod chamber of hydraulic cylinder 14 to prevent damage to the seal of hydraulic cylinder 14 due to excessive pressure; and also to adjust for positional changes due to leakage of hydraulic cylinder 14 during an accident condition, so that the system operates reliably during the accident condition. Since the spring-side connection port CA of the priority valve 27 is provided, the pressure set value of the priority valve 27 is dependent only on the biasing force of the spring and not on the pressure of the secondary line.
The one-way throttle valve 21 is used for controlling the first brake sleeve 901 and the second brake sleeve 902 to be opened quickly so as to realize quick adjustment of positions; and meanwhile, the first brake sleeve 901 and the second brake sleeve 902 are controlled to be closed slowly, so that the outer surface of the piston rod 49 is prevented from being damaged.
The first pressure sensor 601 is used for detecting the pressure value of an oil port P of the low-frequency sound digital intelligent valve 7, the second pressure sensor 602 is used for detecting the pressure value of an oil port T of the low-frequency sound digital intelligent valve 7, the third pressure sensor 603 is respectively used for detecting the pressure values of an oil port A of the low-frequency sound digital intelligent valve 7 and a piston cavity of the hydraulic cylinder 14, and the fourth pressure sensor 604 is respectively used for detecting the pressure values of an oil port B of the low-frequency sound digital intelligent valve 7 and a piston rod cavity of the hydraulic cylinder 14.
The piston rod 49 of the hydraulic cylinder 14 is used for controlling the position of the narrow-side copper plate of the crystallizer, namely the taper control of the crystallizer.
The piston 46 of the hydraulic cylinder 14 is provided with a displacement sensor 15 for position detection of the hydraulic cylinder 14.
The first braking sleeve 901 and the second braking sleeve 902 are uniformly distributed on the inner circumferential inclined surface of the loop 26, and the tin bronze material 28 welded on the inner circumferential side of the first braking sleeve 901 and the second braking sleeve 902 can effectively brake the piston rod 49 by means of the pretightening force of the six pairs of pre-compressed belleville springs 29 arranged at one end of the loop 26, and the outer surface of the piston rod 49 cannot be damaged.
The six pre-compressed belleville springs 29 are paired in pairs of two pieces, reducing the axial distance of the brake 22 and also increasing the braking force.
The compressed air CA realizes the cooling function of the hydraulic components in the low-frequency-response control loop 44, and ensures the reliable operation of the hydraulic components under the severe working conditions of high temperature, high humidity and the like; the compressed air CA enters the cooling air passage 36 from the compressed air passage 37 and then is discharged through the cooling purging groove 35, so that external dirt is prevented from entering the hydraulic cylinder 14 from the dust ring 32, the hydraulic cylinder 14 is prevented from being damaged, and the reliability of the system and the high-reliability operation of the hydraulic cylinder 14 are improved.
The working principle of the invention is as follows:
when the system works, the change-over switch 17 of the electric controller 19 generates a signal +1, and the electromagnet of the electromagnetic valve 12 is electrified. A pressure value P' of the hydraulic system enters a braking oil port 40 of the braking device 22 through the one-way throttle valve 21 and acts on the pressure chamber 39 to overcome the precompression force of the belleville spring 29 so as to realize that the loop 26 moves rightwards, so that the first braking sleeve 901 and the second braking sleeve 902 can reversely move towards the axis of the piston rod 49 under the action of the inner circumferential inclined surface of the loop 26, the braking release of the piston rod 49 of the hydraulic cylinder 14 is realized, and the piston rod 49 can freely move; the digital regulator 16 of the electric controller 19 controls the first low-frequency sound flow rate pulse digital on-off valve 101, the second low-frequency sound flow rate pulse digital on-off valve 102, the third low-frequency sound flow rate pulse digital on-off valve 103 and the fourth low-frequency sound flow rate pulse digital on-off valve 104 in pairs, that is, the digital regulator 16 controls the electromagnets of the first low-frequency sound flow rate pulse digital on-off valve 101 and the second low-frequency sound flow rate pulse digital on-off valve 102 at the same time, or the digital regulator 16 controls the electromagnets of the third low-frequency sound flow rate pulse digital on-off valve 103 and the fourth low-frequency sound flow rate pulse digital on-off valve 104 at the same time. According to the position deviation of the hydraulic cylinder 14 measured by the displacement sensor 15, when the hydraulic cylinder 14 extends and is controlled, the digital regulator 16 generates a signal +1, and the electromagnet of the first low-frequency sound flow pulse digital switch valve 101 is electrified; at the same time, the digital regulator 16 generates a signal-1, and the electromagnet of the second low-frequency sound flow pulse digital switch valve 102 is electrified; extension control of hydraulic cylinder 14 is achieved. Or according to the position deviation of the hydraulic cylinder 14 measured by the displacement sensor 15, when the hydraulic cylinder 14 is controlled to retract, the digital regulator 16 generates a signal +1, and the electromagnet of the third low-frequency sound flow pulse digital switch valve 103 is electrified; at the same time, the digital regulator 16 generates a signal-1, and the electromagnet of the fourth low-frequency sound flow pulse digital switch valve 104 is electrified; retraction control of hydraulic cylinder 14 is effected. According to the extending and retracting functions of the hydraulic cylinder 14, high-precision position control of the hydraulic cylinder 14 is realized, so that the position of the hydraulic cylinder 14 required by the process is ensured, meanwhile, when the position value of the hydraulic cylinder 14 measured by the displacement sensor 15 is within the range value required by the process, the first low-frequency response flow pulse digital switch valve 101, the second low-frequency response flow pulse digital switch valve 102, the third low-frequency response flow pulse digital switch valve 103 and the fourth low-frequency response flow pulse digital switch valve 104 are powered off, and no leakage stopping function exists in the positive and negative directions of an oil path formed by the first low-frequency response flow pulse digital switch valve 101, the second low-frequency response flow pulse digital switch valve 102, the third low-frequency response flow pulse digital switch valve 103 and the fourth low-frequency response flow pulse digital switch valve 104 until the position value of the displacement sensor 15 exceeds the range value required by the process due to tiny leakage of hydraulic components and the hydraulic cylinder 14, the extending and retracting actions of the hydraulic cylinder 14 are triggered, thereby realizing the function of reducing energy consumption.
Furthermore, the hydraulic cylinder 14 can realize a speed stepless regulation function, and the principle is realized by regulating the duty ratio PWM of the first low-frequency-response-flow-rate pulse digital on-off valve 101, the second low-frequency-response-flow-rate pulse digital on-off valve 102, the third low-frequency-response-flow-rate pulse digital on-off valve 103 and the fourth low-frequency-response-flow-rate pulse digital on-off valve 104.
Further, the set value of electrical controller 19 is required to control hydraulic cylinder 14 for a constant or variable speed extension motion, based on the flow-pressure differential equation
Figure GDA0003380837650000131
Therefore, by detecting the pressure difference at two ends of the first low-frequency response flow pulse digital switch valve 101, that is, detecting the difference between the first pressure sensor 601 and the third pressure sensor 603, the duty ratio (PWM) of the first low-frequency response flow pulse digital switch valve 101 is automatically controlled, so that the flow passing through the first low-frequency response flow pulse digital switch valve 101 is automatically controlled, the speed of the hydraulic cylinder 14 is intelligently controlled, and at the moment, the second low-frequency response flow pulse digital switch valve 102 is in a fully open state, the return oil throttling loss of the hydraulic servo system is reduced by the logic array control technology of the low-frequency response flow pulse digital switch valve, and the technical problem that oil is heated seriously due to the valve core inlet and return oil coupling control of the traditional servo valve is solved; similarly, the set value of electrical controller 19, when required to control the constant or variable-speed retraction of hydraulic cylinder 14, is based on the flow-pressure differential equation
Figure GDA0003380837650000132
It can be seen that the duty ratio (PWM) of the third low frequency volume digital pulse switching valve 103 is automatically controlled by detecting the differential pressure across the third low frequency volume digital pulse switching valve 103, i.e. detecting the differential pressure between the fourth pressure sensor 604 and the second pressure sensor 602, so as to automatically control the third low frequency volume digital pulse switching valve 103 to flow through the third low frequency volume digital pulse switching valveThe flow of the valve 103 intelligently controls the speed of the hydraulic cylinder 14, and at the moment, the fourth low-frequency sound flow pulse digital switch valve 104 is in a full-open state, the logic array control technology of the low-frequency sound flow pulse digital switch valve reduces the return oil throttling loss of the hydraulic servo system, and avoids the technical problem of serious oil heating caused by the coupling control of the inlet oil and the return oil of the traditional servo valve spool.
Further, according to the flow-pressure difference equation
Figure GDA0003380837650000133
It can be seen that the set value of the electric controller 19 specifies a certain duty ratio (PWM) of the first low-frequency volume pulse digital on-off valve 101, the second low-frequency volume pulse digital on-off valve 102, the third low-frequency volume pulse digital on-off valve 103, and the fourth low-frequency volume pulse digital on-off valve 104, detects the values of the first pressure sensor 601, the second pressure sensor 602, the third pressure sensor 603, the fourth pressure sensor 604, and the displacement sensor 15, and can automatically determine the hydraulic component that has failed by combining the load parameter identification control algorithm.
The fault state is described as follows:
if the first low-frequency volume-ringing digital pulse switch valve 101 is electrified, the monitor S of the first low-frequency volume-ringing digital pulse switch valve 101 is at the working position, and the measurement value of the third pressure sensor 603 is the pressure value P' of the hydraulic system, the first low-frequency volume-ringing digital pulse switch valve 101 works normally; if the first low-frequency-response flow pulse digital switch valve 101 is electrified, but the monitor S of the first low-frequency-response flow pulse digital switch valve 101 is in a non-working position, the first low-frequency-response flow pulse digital switch valve 101 is in a fault; if the first low-frequency volume digital pulse switch valve 101 is de-energized, but the monitor S of the first low-frequency volume digital pulse switch valve 101 is at the working position, and the third pressure sensor 603 is at the pressure value P' of the hydraulic system, the first low-frequency volume digital pulse switch valve 101 fails.
If the third low-frequency volume impulse digital switch valve 103 is powered on, the monitor S of the third low-frequency volume impulse digital switch valve 103 is at the working position, and the measurement value of the fourth pressure sensor 604 is the pressure value P' of the hydraulic system, the third low-frequency volume impulse digital switch valve 103 works normally; if the third low-frequency-response flow pulse digital switch valve 103 is electrified, but the monitor S of the third low-frequency-response flow pulse digital switch valve 103 is in a non-working position, the third low-frequency-response flow pulse digital switch valve 103 is in a fault; if the third low-frequency volume impulse digital switch valve 103 is de-energized, but the monitor S of the third low-frequency volume impulse digital switch valve 103 is at the working position, and the fourth pressure sensor 604 is at the pressure value P' of the hydraulic system, the third low-frequency volume impulse digital switch valve 103 fails.
If the first low-frequency sound flow digital pulse switch valve 101 and the fourth low-frequency sound flow digital pulse switch valve 104 are both powered, the monitor S of the fourth low-frequency sound flow digital pulse switch valve 104 is at a working position, and the measurement value of the third pressure sensor 603 is the hydraulic system return oil pressure value T', the first low-frequency sound flow digital pulse switch valve 101 works normally; if the first low-frequency response flow digital pulse switch valve 101 and the fourth low-frequency response flow digital pulse switch valve 104 are both powered, but the monitor S of the fourth low-frequency response flow digital pulse switch valve 104 is in a non-working position, and the third pressure sensor 603 is a pressure value P' of the hydraulic system, the fourth low-frequency response flow digital pulse switch valve 104 fails; if the first low-frequency-response-flow digital pulse switch valve 101 is powered on, and the fourth low-frequency-response-flow digital pulse switch valve 104 is powered off, but the monitor S of the fourth low-frequency-response-flow digital pulse switch valve 104 is at the working position, and the third pressure sensor 603 is the hydraulic system return pressure value T', the fourth low-frequency-response-flow digital pulse switch valve 104 fails.
If the third low-frequency sound flow digital pulse switch valve 103 and the second low-frequency sound flow digital pulse switch valve 102 are both powered, the monitor S of the second low-frequency sound flow digital pulse switch valve 102 is at the working position, and the measurement value of the fourth pressure sensor 604 is the hydraulic system return oil pressure value T', the second low-frequency sound flow digital pulse switch valve 102 works normally; if the third low-frequency sound flow pulse digital switch valve 103 and the second low-frequency sound flow pulse digital switch valve 102 are both electrified, but the monitor S of the second low-frequency sound flow pulse digital switch valve 102 is in a non-working position, the second low-frequency sound flow pulse digital switch valve 102 breaks down; if the third low-frequency volume impulse digital switch valve 10 is powered on and the second low-frequency volume impulse digital switch valve 102 is powered off, but the monitor S of the second low-frequency volume impulse digital switch valve 102 is at the working position, and the fourth pressure sensor 604 is the hydraulic system return pressure value T', the second low-frequency volume impulse digital switch valve 102 has a fault.
Furthermore, in the system accident state or in the on-line width-adjusting pouring mode, the change-over switch 17 of the electric controller 19 generates a signal 0, and the electromagnet of the electromagnetic valve 12 has no current. The oil in the pressure chamber 39 of the brake device 22 flows through the oil port P1 of the low frequency response control circuit 44 via the oil passage 40 and then is connected with the oil return port T by the one-way throttle valve 21, which is the hydraulic system return pressure value T ', so that the precompression force of the belleville spring 29 of the brake device 22 overcomes the hydraulic system return pressure value T' of the pressure chamber 39 of the brake device 22, and the loop 26 moves leftward, so that the first brake sleeve 901 and the second brake sleeve 902 can move toward the axial center of the piston rod 49 under the action of the inner circumferential inclined surface of the loop 26, the surfacing tin, green and copper materials 28 reliably brake the piston rod 49, and the piston rod 49 of the hydraulic cylinder 14 is quickly braked at any position needing to be controlled, thereby ensuring long-time continuous casting of the continuous casting machine.
Furthermore, the change-over switch 17 of the electrical controller 19 generates a signal +1, the electromagnet of the electromagnetic valve 12 is energized, and the relay 20 of the leakage alarm circuit 43 sends a signal, which indicates that the leakage of the external pipeline causes the oil to pass through the first check valve 401, causing the relay 20 to operate, and at this time, the electrical controller 19 automatically controls the electromagnet of the electromagnetic valve 12 to be powered off, and prompts the system to have a leakage accident state.
The hydraulic position servo control technology and the fault self-diagnosis method based on the load port logic valve array can be popularized and applied to other hydraulic engineering fields needing to realize intelligent and accurate control of the position of a hydraulic cylinder.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.
The components and structures of the present embodiments that are not described in detail are well known in the art and do not constitute essential structural elements or elements.

Claims (9)

1. A hydraulic servo control system of a digital logic valve array is used for on-line width thermal adjustment of a continuous casting crystallizer, and is characterized in that:
the device consists of a leakage alarm loop (43), a low-frequency response control loop (44), a hydraulic cylinder (14), a displacement sensor (15) and an electric controller (19); an oil port P of the leakage alarm loop (43) is connected with an oil port P of the low-frequency response control loop (44), and an oil port T of the leakage alarm loop (43) is connected with an oil port T of the low-frequency response control loop (44); an oil port A of the low-frequency response control loop (44) is connected with an oil port (42) of a piston cavity of the hydraulic cylinder (14); an oil port B of the low-frequency response control loop (44) is connected with an oil port (41) of a piston rod cavity of the hydraulic cylinder (14); an oil port P1 of the low-frequency response control loop (44) is connected with a brake oil port (40) of the hydraulic cylinder (14); the compressed air CA is respectively connected with a cooling air port CA of the low-frequency-response control loop (44) and a compressed air passage (37) of the hydraulic cylinder (14);
the leakage alarm loop (43) consists of a filter (11), a ball valve (13), a relay (20), a first one-way valve (401), a third throttle valve (203), a second one-way valve (402) and an electromagnetic valve (12); a main pressure pipeline P0 of the leakage alarm loop (43) is respectively connected with an oil port A of the relay (20), an oil port A of the first one-way valve (401) and an oil port A of the third throttle valve (203) through the filter (11), and an oil port P of the electromagnetic valve (12) is respectively connected with an oil port B of the relay (20), an oil port B of the first one-way valve (401) and an oil port B of the third throttle valve (203); an oil port B of the electromagnetic valve (12) is connected with an oil port P of the leakage alarm loop (43); a main oil return pipeline T0 of the leakage alarm loop (43) is respectively connected with an oil port T of the electromagnetic valve (12) and an oil port T of the leakage alarm loop (43) through an oil port B and an oil port A of the second one-way valve (402); a main pressure pipeline P0 of the leakage alarm loop (43) is connected with a main oil return pipeline T0 through a ball valve (13);
the low-frequency response control loop (44) consists of a first hydraulic control one-way valve (801), a second hydraulic control one-way valve (802), an overflow valve (10), a sequence valve (27), a third one-way valve (403) and a low-frequency response digital intelligent valve (7); an oil port A of the low-frequency response digital intelligent valve (7) is connected with an oil port (42) of a piston cavity of the hydraulic cylinder (14) through an oil port A of the first hydraulic control one-way valve (801) and an oil port B; an oil port B of the low-frequency-response digital intelligent valve (7) is connected with an oil port (41) of a piston rod cavity of the hydraulic cylinder (14) through an oil port A of a second hydraulic control one-way valve (802) through the oil port B; a control oil port X of the first hydraulic control one-way valve (801) and a control oil port X of the second hydraulic control one-way valve (802) are respectively connected with an oil port P of the low-frequency response control loop (44), and an oil drainage port Y of the first hydraulic control one-way valve (801) and an oil drainage port Y of the second hydraulic control one-way valve (802) are respectively connected with an oil port T of the low-frequency response control loop (44); an oil port P of the low-frequency response control loop (44) is connected with an oil port P1 of the low-frequency response control loop (44) through an oil port A of the one-way throttle valve (21) and an oil port B; an oil port A of the low-frequency response control loop (44) is connected with an oil port T of the low-frequency response control loop (44) through an oil port P of the overflow valve (10) through the oil port T; an oil port B of the low-frequency response control loop (44) is connected with an oil port A of the low-frequency response control loop (44) through an oil port P of the sequence valve (27) and an oil port T, and the oil port B of the low-frequency response control loop (44) is connected with the oil port T of the low-frequency response control loop (44) through an oil port B of the third check valve (403) and the oil port A;
the low-frequency sound digital intelligent valve (7) consists of a first low-frequency sound flow pulse digital switch valve (101), a second low-frequency sound flow pulse digital switch valve (102), a third low-frequency sound flow pulse digital switch valve (103), a fourth low-frequency sound flow pulse digital switch valve (104), a first pressure sensor (601), a second pressure sensor (602), a third pressure sensor (603) and a fourth pressure sensor (604); wherein an oil port P of the low-frequency response digital intelligent valve (7) is respectively connected with an oil port P of the first low-frequency response flow digital pulse switch valve (101) and an oil port P of the third low-frequency response flow digital pulse switch valve (103), an oil port T of the low-frequency sound digital intelligent valve (7) is respectively connected with an oil port P of a fourth low-frequency sound flow pulse digital switch valve (104) and an oil port A of a second low-frequency sound flow pulse digital switch valve (102), the oil port A of the low-frequency sound digital intelligent valve (7) is respectively connected with the oil port A of a first low-frequency sound flow pulse digital switch valve (101) and the oil port A of the fourth low-frequency sound flow pulse digital switch valve (104), an oil port B of the low-frequency response digital intelligent valve (7) is respectively connected with an oil port A of a third low-frequency response flow digital pulse switch valve (103) and an oil port P of a second low-frequency response flow digital pulse switch valve (102); a first pressure sensor (601) is arranged at an oil port P of the low-frequency response digital intelligent valve (7), a second pressure sensor (602) is arranged at an oil port T of the low-frequency response digital intelligent valve (7), a third pressure sensor (603) is arranged at an oil port A of the low-frequency response digital intelligent valve (7), and a fourth pressure sensor (604) is arranged at an oil port B of the low-frequency response digital intelligent valve (7);
the hydraulic cylinder (14) comprises a cylinder body (45), a piston (46), a piston rod (49), a front flange (24), a braking device (22), a loop (26) and a front end cover (31); the cylinder body (45) is separated into a piston cavity and a piston rod cavity by the piston (46), a guide ring (47) and a sealing ring (48) are arranged on the piston, and the piston (46) and the piston rod (49) are of an integral structure; the front flange (24) is connected with the cylinder body (45) through threads, and the front end cover (31) fixes the braking device (22) on the front flange (24) through a bolt (34) and an elastic pad (33); the brake device (22) is provided with three sets of first guide belts (501), a main seal (25), a first auxiliary seal (301) and a static seal (23), and a brake release oil path and a compressed air path (37) are arranged on the brake device (22); the loop (26) is provided with two sets of second auxiliary seals (302), two sets of third auxiliary seals (303) and two sets of second guide belts (502); the first brake sleeve (901) and the second brake sleeve (902) are uniformly distributed on the inner circumferential inclined plane of the loop (26), and a tin bronze material (28) is welded on the inner circumferential sides of the first brake sleeve (901) and the second brake sleeve (902) in a stacking mode; one end of the loop (26) is provided with six pairs of pre-compression butterfly springs (29); the front end cover (31) is provided with a static seal (23), three sets of first guide belts (501), a dust ring (32), a cooling air passage (36) and a cooling purging groove (35); a displacement sensor (15) is arranged on the hydraulic cylinder (14);
the electric controller (19) consists of a comparator (18), a digital regulator (16) and a change-over switch (17); the digital regulator (16) is respectively connected with a first low-frequency sound flow pulse digital switch valve (101), a second low-frequency sound flow pulse digital switch valve (102), a third low-frequency sound flow pulse digital switch valve (103) and a fourth low-frequency sound flow pulse digital switch valve (104) through cables; the change-over switch (17) is connected with the electromagnetic valve (12) through a cable; the comparator (18) is respectively connected with the displacement sensor (15), the relay (20), the first pressure sensor (601), the second pressure sensor (602), the third pressure sensor (603), the fourth pressure sensor (604), the first low-frequency sound flow pulse digital switch valve (101) monitor S, the second low-frequency sound flow pulse digital switch valve (102) monitor S, the third low-frequency sound flow pulse digital switch valve (103) monitor S and the fourth low-frequency sound flow pulse digital switch valve (104) monitor S through cables.
2. The hydraulic servo control system of a digital logic valve array of claim 1, wherein:
a change-over switch (17) of an electric controller (19) generates a signal 0, and an electromagnet of the electromagnetic valve (12) has no current; oil liquid of a pressure cavity (39) of the braking device (22) flows through an oil port P1 of the low-frequency response control loop (44) through a braking oil port (40), then is connected with the oil port P of the low-frequency response control loop (44) through an oil port A through an oil port B of the one-way throttle valve (21), the precompression force of a butterfly spring (29) of the braking device (22) overcomes the oil return pressure value T' of a hydraulic system of the pressure cavity (39) of the braking device (22), a loop (26) moves leftwards, a first braking sleeve (901) and a second braking sleeve (902) can move towards the axis of a piston rod (49) under the action of an inner circumference inclined plane of the loop (26), so that a surfacing welding tin bronze material (28) can reliably brake the piston rod (49), and quick braking of the piston rod (49) of the hydraulic cylinder (14) is realized.
3. The hydraulic servo control system of a digital logic valve array of claim 1, wherein:
the low-frequency response digital intelligent valve (7) is used for controlling the position of a hydraulic cylinder (14), a first damper (201) is arranged on oil ports A of a first low-frequency response flow pulse digital switch valve (101) and a fourth low-frequency response flow pulse digital switch valve (104), a second damper (202) is arranged on oil ports A of a second low-frequency response flow pulse digital switch valve (102) and a third low-frequency response flow pulse digital switch valve (103), and the position of the hydraulic cylinder (14) can be accurately controlled by detecting the real-time position of the hydraulic cylinder (14) through a displacement sensor (15); the first low-frequency sound flow pulse digital switch valve (101), the second low-frequency sound flow pulse digital switch valve (102), the third low-frequency sound flow pulse digital switch valve (103) and the fourth low-frequency sound flow pulse digital switch valve (104) are cone valve type or ball valve type switch valves.
4. The hydraulic servo control system of a digital logic valve array of claim 1, wherein:
the first pressure sensor (601) is used for detecting the pressure value of an oil port P of the low-frequency sound digital intelligent valve (7), the second pressure sensor (602) is used for detecting the pressure value of an oil port T of the low-frequency sound digital intelligent valve (7), the third pressure sensor (603) is respectively used for detecting the pressure values of an oil port A of the low-frequency sound digital intelligent valve (7) and a piston cavity of the hydraulic cylinder (14), and the fourth pressure sensor (604) is respectively used for detecting the pressure values of an oil port B of the low-frequency sound digital intelligent valve (7) and a piston rod cavity of the hydraulic cylinder (14).
5. The hydraulic servo control system of a digital logic valve array of claim 1, wherein:
the first brake sleeve (901) and the second brake sleeve (902) are uniformly distributed on the inner circumferential inclined plane of the movable sleeve (26), and the pretightening force of six pairs of pre-compressed butterfly springs (29) arranged at one end of the movable sleeve (26) enables the inner circumferential sides of the first brake sleeve (901) and the second brake sleeve (902) to be overlaid and welded with tin bronze materials (28) to brake the piston rod (49); six pairs of pre-compressed belleville springs (29) are paired with two plates to reduce the axial distance of the brake (22).
6. The hydraulic servo control system of a digital logic valve array of claim 1, wherein:
the compressed air CA realizes the cooling function of the hydraulic components in the low-frequency response control loop (44); the compressed air CA enters the cooling air passage (36) from the compressed air passage (37) and then is discharged through the cooling purging groove (35), so that external dirt is prevented from entering the hydraulic cylinder (14) from the dust ring (32), the hydraulic cylinder (14) is prevented from being damaged, and the reliability of the system and the high-reliability operation of the hydraulic cylinder (14) are improved.
7. A method of controlling a hydraulic servo control system of a digital logic valve array as claimed in any one of claims 1 to 6, wherein:
when the system works, a change-over switch (17) of an electric controller (19) generates a signal +1, and an electromagnet of the electromagnetic valve (12) is electrified; a pressure value P' of the hydraulic system enters a braking oil port (40) of a braking device (22) through a one-way throttle valve (21) and acts on a pressure cavity (39) to overcome the precompression force of a belleville spring (29) to realize that a loop (26) moves rightwards, so that a first braking sleeve (901) and a second braking sleeve (902) can move reversely towards the axis of a piston rod (49) under the action of an inner circumferential inclined plane of the loop (26), the braking release of the piston rod (49) of the hydraulic cylinder (14) is realized, and the piston rod (49) can move freely; a digital regulator (16) of the electric controller (19) controls the first low-frequency sound flow pulse digital switch valve (101), the second low-frequency sound flow pulse digital switch valve (102), the third low-frequency sound flow pulse digital switch valve (103) and the fourth low-frequency sound flow pulse digital switch valve (104) in pairs, namely the digital regulator (16) simultaneously controls electromagnets of the first low-frequency sound flow pulse digital switch valve (101) and the second low-frequency sound flow pulse digital switch valve (102), or the digital regulator (16) simultaneously controls electromagnets of the third low-frequency sound flow pulse digital switch valve (103) and the fourth low-frequency sound flow pulse digital switch valve (104); according to the real-time position of the hydraulic cylinder (14) measured by the displacement sensor (15), when the hydraulic cylinder (14) is extended and controlled, the digital regulator (16) generates a signal +1, and an electromagnet of the first low-frequency sound flow pulse digital switch valve (101) is electrified; meanwhile, the digital regulator (16) generates a signal-1, and an electromagnet of the second low-frequency sound flow pulse digital switch valve (102) is electrified; realizing the extension control of the hydraulic cylinder (14); or according to the real-time position of the hydraulic cylinder (14) measured by the displacement sensor (15), when the hydraulic cylinder (14) is controlled to retract, the digital regulator (16) generates a signal +1, and the electromagnet of the third low-frequency sound flow pulse digital switch valve (103) is electrified; meanwhile, the digital regulator (16) generates a signal-1, and an electromagnet of the fourth low-frequency sound flow pulse digital switch valve (104) is electrified; the retraction control of the hydraulic cylinder (14) is realized; according to the extending and retracting functions of the hydraulic cylinder (14), high-precision position control of the hydraulic cylinder (14) is achieved, the position of the hydraulic cylinder (14) required by the process is guaranteed, meanwhile when the position value of the hydraulic cylinder (14) measured by the displacement sensor (15) is within the range value required by the process, the first low-frequency sound flow pulse digital switch valve (101), the second low-frequency sound flow pulse digital switch valve (102), the third low-frequency sound flow pulse digital switch valve (103) and the fourth low-frequency sound flow pulse digital switch valve (104) are powered off, and the oil path formed by the first low-frequency sound flow pulse digital switch valve (101), the second low-frequency sound flow pulse digital switch valve (102), the third low-frequency sound flow pulse digital switch valve (103) and the fourth low-frequency sound flow pulse digital switch valve (104) has no leakage stopping function in the positive and negative directions until the hydraulic cylinder measured by the displacement sensor (15) is subjected to tiny leakage due to the hydraulic components and the hydraulic cylinder (14) (14) The real-time position value exceeds the range value of the process requirement to trigger the extending and retracting actions of the hydraulic cylinder (14), thereby realizing the function of reducing energy consumption;
the hydraulic cylinder (14) can realize the function of stepless speed regulation and is realized by regulating the duty ratio PWM of a first low-frequency sound flow pulse digital switch valve (101), a second low-frequency sound flow pulse digital switch valve (102), a third low-frequency sound flow pulse digital switch valve (103) and a fourth low-frequency sound flow pulse digital switch valve (104);
when the set value of the electric controller (19) needs to control the hydraulic cylinder (14) to extend and move at a constant speed or a variable speed, the flow-pressure difference equation is used
Figure FDA0003418359700000061
The method has the advantages that the pressure difference between two ends of the first low-frequency sound flow pulse digital switch valve (101) is detected, namely the difference between the first pressure sensor (601) and the third pressure sensor (603) is detected, so that the duty ratio PWM of the first low-frequency sound flow pulse digital switch valve (101) is automatically controlled, the flow passing through the first low-frequency sound flow pulse digital switch valve (101) is automatically controlled, the speed of a hydraulic cylinder (14) is intelligently controlled, at the moment, the second low-frequency sound flow pulse digital switch valve (102) is in a full-open state, the return oil throttling loss of a hydraulic servo system is reduced by the logic array control technology of the low-frequency sound flow pulse digital switch valve, and the technical problem that oil is seriously heated due to the coupling control of the inlet oil and the return oil of a servo valve core is solved; likewise, when the set value of the electrical controller (19) is required to control the constant or variable-speed retraction movement of the hydraulic cylinder (14), the flow-pressure difference equation is followed
Figure FDA0003418359700000062
Therefore, the pressure difference between two ends of the third low-frequency sound flow pulse digital switch valve (103) is detected, namely the difference value between the fourth pressure sensor (604) and the second pressure sensor (602) is detected, so that the duty ratio PWM of the third low-frequency sound flow pulse digital switch valve (103) is automatically controlled, the flow passing through the third low-frequency sound flow pulse digital switch valve (103) is automatically controlled, the speed of the hydraulic cylinder (14) is intelligently controlled, and the fourth low-frequency sound flow pulse digital switch valve (104) is in a full-open state at the moment; wherein: in the flow-pressure difference equation, CdIs the flow coefficient, ω is the area gradient of the valve, xvFor spool displacement, ρ is oil density, PsSupply pressure to the system, PLIs the load pressure.
8. A method of fault self-diagnosis of a hydraulic servo control system of a digital logic valve array as claimed in any one of claims 1 to 6, wherein:
according to the flow-pressure difference equation
Figure FDA0003418359700000063
The set value of the electric controller (19) gives a certain duty ratio PWM to a first low-frequency sound flow pulse digital switch valve (101), a second low-frequency sound flow pulse digital switch valve (102), a third low-frequency sound flow pulse digital switch valve (103) and a fourth low-frequency sound flow pulse digital switch valve (104), and the values of a first pressure sensor (601), a second pressure sensor (602), a third pressure sensor (603), a fourth pressure sensor (604) and a displacement sensor (15) are detected to automatically judge the hydraulic component with the fault;
the specific method comprises the following steps: the first low-frequency sound flow pulse digital switch valve (101) is electrified, a monitor S of the first low-frequency sound flow pulse digital switch valve (101) is in a working position, and meanwhile, the measured value of the third pressure sensor (603) is a pressure value P' of the hydraulic system, so that the first low-frequency sound flow pulse digital switch valve (101) works normally; if the first low-frequency sound flow pulse digital switch valve (101) is electrified, but a monitor S of the first low-frequency sound flow pulse digital switch valve (101) is in a non-working position, the first low-frequency sound flow pulse digital switch valve (101) is in a fault state; if the first low-frequency response flow pulse digital switch valve (101) is de-energized, but the monitor S of the first low-frequency response flow pulse digital switch valve (101) is at the working position, and the third pressure sensor (603) is the pressure value P' of the hydraulic system, the first low-frequency response flow pulse digital switch valve (101) is in failure;
if the third low-frequency sound flow pulse digital switch valve (103) is electrified, the monitor S of the third low-frequency sound flow pulse digital switch valve (103) is at a working position, and the measurement value of the fourth pressure sensor (604) is the pressure value P' of the hydraulic system, the third low-frequency sound flow pulse digital switch valve (103) works normally; if the third low-frequency sound flow pulse digital switch valve (103) is electrified, but a monitor S of the third low-frequency sound flow pulse digital switch valve (103) is in a non-working position, the third low-frequency sound flow pulse digital switch valve (103) is in a fault state; if the third low-frequency sound flow pulse digital switch valve (103) is de-energized, but the monitor S of the third low-frequency sound flow pulse digital switch valve (103) is at the working position, and the fourth pressure sensor (604) is the pressure value P' of the hydraulic system, the third low-frequency sound flow pulse digital switch valve (103) is in failure;
if the first low-frequency sound flow pulse digital switch valve (101) and the fourth low-frequency sound flow pulse digital switch valve (104) are electrified, a monitor S of the fourth low-frequency sound flow pulse digital switch valve (104) is in a working position, and meanwhile, the measured value of the third pressure sensor (603) is the hydraulic system return oil pressure value T', the first low-frequency sound flow pulse digital switch valve (101) works normally; if the first low-frequency response flow pulse digital switch valve (101) and the fourth low-frequency response flow pulse digital switch valve (104) are electrified, but a monitor S of the fourth low-frequency response flow pulse digital switch valve (104) is in a non-working position, and the third pressure sensor (603) is a pressure value P' of the hydraulic system, the fourth low-frequency response flow pulse digital switch valve (104) breaks down; if the first low-frequency sound flow pulse digital switch valve (101) is electrified, the fourth low-frequency sound flow pulse digital switch valve (104) is not electrified, but a monitor S of the fourth low-frequency sound flow pulse digital switch valve (104) is in a working position, and meanwhile, the third pressure sensor (603) is a hydraulic system return oil pressure value T', the fourth low-frequency sound flow pulse digital switch valve (104) breaks down;
if the third low-frequency sound flow pulse digital switch valve (103) and the second low-frequency sound flow pulse digital switch valve (102) are electrified, a monitor S of the second low-frequency sound flow pulse digital switch valve (102) is in a working position, and meanwhile, the measured value of the fourth pressure sensor (604) is the hydraulic system oil return pressure value T', the second low-frequency sound flow pulse digital switch valve (102) works normally; if the third low-frequency sound flow pulse digital switch valve (103) and the second low-frequency sound flow pulse digital switch valve (102) are electrified, but a monitor S of the second low-frequency sound flow pulse digital switch valve (102) is in a non-working position, the second low-frequency sound flow pulse digital switch valve (102) breaks down; if the third low-frequency sound flow pulse digital switch valve (10) is electrified, the second low-frequency sound flow pulse digital switch valve (102) is not electrified, but a monitor S of the second low-frequency sound flow pulse digital switch valve (102) is in a working position, and meanwhile, the fourth pressure sensor (604) is a hydraulic system return oil pressure value T', the second low-frequency sound flow pulse digital switch valve (102) breaks down.
9. The fault self-diagnosis method according to claim 8, characterized in that:
the signal +1 is generated by a change-over switch (17) of the electric controller (19), the electromagnet of the electromagnetic valve (12) is electrified, a relay (20) of the leakage alarm loop (43) sends a signal to indicate that the leakage of the external pipeline causes the oil to pass through the first one-way valve (401), so that the relay (20) acts, and at the moment, the electric controller (19) automatically controls the electromagnet of the electromagnetic valve (12) to be powered off to prompt the system to have a leakage accident state.
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5776303A (en) * 1980-10-28 1982-05-13 Kubota Ltd Control unit for shuttlecock truck
US6257859B1 (en) * 1999-01-25 2001-07-10 Nissei Plastic Industrial Co., Ltd. Hydraulic circuit of an injection molding machine
CN2815552Y (en) * 2005-08-08 2006-09-13 西安重型机械研究所 Hydraulic controldevice for crystallizer hydraulic vibrating device
CN103244472A (en) * 2013-05-08 2013-08-14 中国重型机械研究院股份公司 Servo hydraulic cylinder valve system for hydraulically balancing gravity load of crystallizer
CN105988445A (en) * 2015-02-28 2016-10-05 宝山钢铁股份有限公司 Continuous casting electro hydraulic servo system signal acquisition monitoring system and signal acquisition monitoring method
CN107939784A (en) * 2017-11-18 2018-04-20 四川长江液压天成机械有限公司 A kind of multi-hydraulic-cylinder control system and its control method
CN108843630A (en) * 2018-07-23 2018-11-20 中国重型机械研究院股份公司 A kind of position and the continuously adjustable driven roller of pressure depress hydraulic control system
CN110131240A (en) * 2019-05-16 2019-08-16 中国重型机械研究院股份公司 A kind of hydraulic position and pressure closed loop control dynamic static simulation pilot system and method

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5776303A (en) * 1980-10-28 1982-05-13 Kubota Ltd Control unit for shuttlecock truck
US6257859B1 (en) * 1999-01-25 2001-07-10 Nissei Plastic Industrial Co., Ltd. Hydraulic circuit of an injection molding machine
CN2815552Y (en) * 2005-08-08 2006-09-13 西安重型机械研究所 Hydraulic controldevice for crystallizer hydraulic vibrating device
CN103244472A (en) * 2013-05-08 2013-08-14 中国重型机械研究院股份公司 Servo hydraulic cylinder valve system for hydraulically balancing gravity load of crystallizer
CN105988445A (en) * 2015-02-28 2016-10-05 宝山钢铁股份有限公司 Continuous casting electro hydraulic servo system signal acquisition monitoring system and signal acquisition monitoring method
CN107939784A (en) * 2017-11-18 2018-04-20 四川长江液压天成机械有限公司 A kind of multi-hydraulic-cylinder control system and its control method
CN108843630A (en) * 2018-07-23 2018-11-20 中国重型机械研究院股份公司 A kind of position and the continuously adjustable driven roller of pressure depress hydraulic control system
CN110131240A (en) * 2019-05-16 2019-08-16 中国重型机械研究院股份公司 A kind of hydraulic position and pressure closed loop control dynamic static simulation pilot system and method

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