3511results about "Fluid-pressure actuator testing" patented technology

The invention relates to a split type electro-hydraulic direct-driven non-retractable fin stabilizer hydraulic system which comprises a hydraulic unit and an actuating mechanism which are independently arranged, and the actuating mechanism comprises fin rotating oil cylinders which are symmetrically arranged; a bidirectional hydraulic pump driven by a servo motor forms a closed fin rotating loop; the bidirectional hydraulic pump driven by the servo motor, the hydraulic unit and the actuating mechanism form an electro-hydraulic direct-drive fin stabilizer device; the control loop is composed of a gyroscope, a controller and an executing mechanism, and the gyroscope detects the rolling angular velocity of the ship and generates a fin rotating instruction signal; the controller compares the instruction signal with the fin angle feedback signal and outputs a servo motor rotating speed instruction; the servo driver controls the servo motor to rotate forwards and backwards, the bidirectional hydraulic pump is driven to adjust the displacement of the fin rotating oil cylinder, and therefore the fin is driven to rotate. A valve control or pump control type hydraulic system adopted by a traditional fin stabilizer is replaced, integrated optimization, light weight, high efficiency, high reliability and low noise of the fin stabilizer hydraulic system are achieved, and the occupied space of equipment is reduced.

The invention discloses a hydraulic control system, which belongs to the field of hydraulic control, and comprises a power execution module, a control regulation module and a sensing feedback module, in the slurry manufacturing stage, data are collected through a sensor, the abnormal condition of the slurry temperature is detected to judge whether the slurry temperature is adjusted or not, and based on the real-time slurry viscosity, the rotating speed of a stirring shaft is adjusted in a self-adaptive mode by adjusting the hydraulic flow of a hydraulic motor of a stirring driver; acquiring driver data to monitor a control instruction implementation result, performing abnormality evaluation analysis on a driver through threshold judgment and abnormality score calculation, and generating an updated driver control signal after a driver instruction regeneration signal is received; monitoring abnormal conditions of data acquired by various deployed sensors, monitoring abnormal data of the sensors, and monitoring duration of the abnormal data so as to carry out abnormal early warning and generate abnormal early warning information; the problem that the slurry temperature of die-casting equipment under hydraulic control is difficult to adaptively adjust and disturb is solved.

The invention discloses a fault diagnosis method of a hydraulic system and an intelligent early warning device, and relates to the technical field of hydraulic systems.The fault diagnosis method comprises the steps that an operation model of the hydraulic system is established according to ideal environment parameters, and standard operation parameters are imported into the operation model to obtain ideal performance coefficients of the hydraulic system; calculating an equipment operation deviation coefficient according to the ideal environment parameters, presetting a system operation early warning threshold value according to the equipment operation deviation coefficient, establishing an environment prediction model, integrating multiple groups of predicted environment change data to obtain an environment deviation oscillogram, and further delimiting a normal monitoring time period, a peak monitoring time period and a key monitoring time period; a corresponding monitoring frequency band is set, early warning judgment is performed according to a deviation value of an actual performance coefficient and an ideal performance coefficient of equipment, and fault prediction is realized before the hydraulic system breaks down due to interference of environmental factors in combination with interference influence of the environmental factors on operation of the hydraulic system. Economic losses caused by the fact that problems can only be found after faults occur are avoided.

The invention discloses a hydraulic system intelligent fault diagnosis method based on a diffusion model data enhancement framework, and the method comprises the following steps: firstly providing a diffusion model-based data enhancement framework, carrying out the fault simulation of a hydraulic system through a simulation model, converting a time domain signal into a gray image, and achieving the data enhancement through a diffusion model; carrying out quantitative evaluation on the quality of the generated image, and constructing an enhanced hydraulic system fault data set; based on the proposed framework, a dual-domain adversarial neural network model fused with an attention mechanism is proposed, the weight of a loss function of two domain discriminators is adjusted so as to realize global and local feature adaptive fusion optimization, adversarial training is realized through a gradient inversion layer, and the adaptive fusion optimization of global and local features is realized. Experimental fault state data serve as a test set to be input into a model for fault diagnosis, and the superiority of the method on indexes such as accuracy is verified through comparison of traditional models such as DANN and CNN. In addition, the method is simple and easy to implement, and is suitable for intelligent fault diagnosis of the hydraulic system under the zero sample condition.

The invention relates to the technical field of response time testing of electro-hydraulic proportional valves, and discloses a response time testing method and system of an electro-hydraulic proportional valve, and the method comprises the steps: collecting multi-point pressure, step response, pipeline length and medium parameters, and unifying the time reference to obtain an original pressure sequence; constructing an inverse filter spectrum to remove damping interference so as to recover a sharp peak value; lagging offset is calculated according to pipeline and medium parameters, time delay compensation is carried out, and an alignment sequence is obtained; intercepting a non-stationary segment to eliminate residual delay deviation; constructing a response dynamic data set, extracting harmonic frequency domain representation, and reconstructing a pressure sequence through inverse transformation and superposition of compensation factors; and calculating a deviation integral quantity, adjusting a dynamic compensation parameter, performing weighted correction, and outputting an optimized reconstruction response sequence. According to the method, accurate reconstruction of the real pressure response of the proportional valve can be realized, so that the accuracy and the reliability of response time testing are improved.

The invention relates to an energy accumulator durability test method and system, and the system comprises an extreme working condition simulation module which can achieve high-voltage, wide-temperature-range and high-frequency dynamic loading; the multi-sensor monitoring network integrates a fiber bragg grating strain sensor, a three-axis acceleration sensor and an acoustic emission sensor to realize collaborative monitoring of strain, vibration and microcracks; the intelligent control and energy recovery module is combined with a fuzzy PID and reinforcement learning algorithm, a magnetorheological fluid generator and a super capacitor bank, so that the control precision and the energy utilization rate are improved; and the data analysis and life evaluation platform accurately predicts the residual life by using an improved Bayesian network model and a real-time health index calculation module. According to the test method, a loading mode is dynamically adjusted through a real-time health index, an energy recovery strategy is optimized, and life early warning is triggered. The invention breaks through the limitation of the traditional test and provides an integrated solution.

The invention provides an underground coal mine air and water pumping switching electro-hydraulic control system and method, the electro-hydraulic control system comprises an air supply control module, a water supply control module, a negative pressure control module and an oil supply module, and the method adopts a remote control system to control the underground coal mine air and water pumping switching electro-hydraulic control system. According to the underground coal mine air and water pumping switching electro-hydraulic control system, air and water pumping electric control rapid opening and closing and rapid switching of different functions are achieved, the automation degree of air and water pumping switching is improved, and the air and water pumping switching time is shortened; and meanwhile, when dangerous working conditions that gas accumulation exceeds the limit due to hole blocking behind the drill hole or carbon monoxide gas appears in the drill hole and the like, rapid and automatic response processing can be achieved. The air and water pumping conversion efficiency is improved, the labor intensity of workers is relieved, and key technical support is provided for coal mine underground automatic drilling whole-process operation.

The invention relates to a high-precision hydraulic charging regulation and control method and system based on a PID and MPC combined algorithm, and the method comprises the steps: collecting a pulse pressure waveform borne by a pressure-bearing part under a target working condition, and collecting a corresponding relation between a control instruction of the opening degree of a regulating valve and the pulse pressure waveform, constructing a pulse pressure waveform library to update a target waveform of the target working condition; creating a state space model to update dynamic characteristics of the hydraulic charging system, dynamically optimizing pre-regulated first-step control input through an MPC algorithm according to the dynamic characteristics, and updating a real waveform tracking target waveform of prediction output in a rolling manner until prediction similarity meets a set threshold value of the target waveform; and in response to the condition that the predicted similarity meets a set threshold value, selecting a PID algorithm to perform feedback adjustment and dynamic compensation on the control input of the real waveform, and outputting target control input simulating the target waveform under the target working condition. The precision, efficiency and flexibility of regulation and control of the hydraulic filling system can be improved.

The invention relates to the technical field of ship hydraulic monitoring, and discloses a marine ship hydraulic oil cylinder state monitoring and sealing performance early warning system. A multi-source sensing data acquisition module of the system synchronously obtains multi-dimensional time sequence operation data of an oil cylinder through a vibration sensor, a pressure sensor and a temperature sensor; the data preprocessing fusion module is used for carrying out noise suppression, timestamp alignment and multi-modal fusion on the data to generate a standardized oil cylinder state feature sequence; the sealing characteristic depth extraction module is used for analyzing sealing cavity pressure fluctuation, piston rod displacement oscillation and sealing piece deformation trend characteristics from the characteristic sequence; the multi-scale state evaluation module is used for calculating a sealing performance degradation gradient and a dynamic operation stability coefficient according to the characteristics; and the early warning decision generation module is used for generating a sealing failure risk level and an early warning control instruction based on the calculation result. According to the system, stable operation of the oil cylinder is guaranteed, and the maintenance cost and the safety risk are reduced.

The invention provides an intelligent optimization control method for stable operation of a hydraulic system in a complex environment, which comprises the following steps of: aiming at an abnormal mode, optimizing power configuration parameters by adopting a genetic algorithm, determining a standby pump activation threshold value and a main pump switching condition, and obtaining a power redundancy scheme; according to the slow response reason, pipeline interface data are obtained, a feedback control mechanism is adopted to adjust valve group cooperation parameters, and a rapid pressure adjustment sequence is obtained; acquiring real-time feedback data according to the final optimization instruction, and processing high-temperature and high-dust influence through an iterative updating process to obtain stable operation configuration; according to the stable operation configuration, the state of the whole system is judged, and if the state meets the preset standard, a cooperative control result is output and used for maintaining continuous operation of the hydraulic system in the complex environment.

The invention discloses a multi-information fusion hydraulic cylinder internal leakage fault diagnosis method, and relates to the technical field of hydraulic cylinder fault diagnos.The hydraulic cylinder internal leakage fault diagnosis method comprises the steps that firstly, a hydraulic cylinder heavy load, time-varying and nonlinear motion curve and a test system based on a multi-source sensor are constructed, and internal leakage fault evolution under the actual working condition is simulated; and secondly, developing a hybrid deep learning semi-supervised feature fusion framework based on a convolutional auto-encoder, a multi-head attention mechanism, residual connection and a bidirectional sequential network, and enhancing the characterization learning ability of a multi-source signal in a complex and multi-noise environment through omnibearing deep feature decoupling. And finally, feature extraction and fusion are realized by using the displacement error and the pressure signal, and fault diagnosis is completed. Experiments show that compared with a comparison model, the diagnosis accuracy of the provided model and feature fusion strategy is improved by 3.95%; under-3 decibel noise, the accuracy is improved by 2.33%, and the scheme has high accuracy, reliability and generalization performance.

The invention belongs to the technical field of hydraulic transmission and control, and discloses a high-precision positioning control method and system of a servo electro-hydraulic actuator. Real-time operation parameters of a servo electro-hydraulic actuator under different working frequencies are obtained, a servo valve dynamic return difference characteristic curve is constructed, a return difference characteristic change mode is extracted, and a dynamic influence model of return difference characteristic change on positioning precision is established. Based on the model, a frequency self-adaptive compensation strategy is designed in combination with a pressure fluctuation value of a hydraulic system, and real-time correction of a servo valve control signal is achieved. According to the method, a differentiation strategy combining low-frequency feed-forward compensation and high-frequency feedback compensation is innovatively adopted, a smooth transition mechanism is designed, and the problem that the positioning precision fluctuates under the frequency change working condition in a traditional control method is solved. According to the invention, high-precision positioning control of the servo electro-hydraulic actuator in a full frequency band range is realized, and the positioning precision and stability of the system under a dynamic working condition are improved.

The invention relates to the technical field of pressure adjusting devices, in particular to a self-adaptive pressure adjusting system and method for a double-roller rolling machine, and the system comprises a pressure intensity judgment module, a section analysis module, a deformation characteristic module, a hydraulic adjusting module and a coupling correction module. According to the method, the yield risk is recognized in advance by obtaining and analyzing the roller contact pressure difference value in real time, recognizing the asymmetric trend of the left pressure and the right pressure in combination with a support vector mechanism to judge the deviation direction, dynamically segmenting the section diameter and calculating the difference to improve the deformation resolution, and vectorizing and analyzing the included angle relation between the section deformation and the roller displacement; in hydraulic analysis, time delay and valve control flow velocity are coupled, pressure regulation continuity is guaranteed, roller posture change is judged through cooperation of a roller shaft and a section trend, hydraulic output is dynamically corrected, and stable pressure regulation and intelligent adaptation are achieved.

The invention relates to the technical field of intelligent control of heavy equipment, in particular to a hydraulic synchronous intelligent control system for segmented turnover of an overweight steel structure, and discloses the hydraulic synchronous intelligent control system for segmented turnover of the overweight steel structure. According to the system, full-field strain data of a structure surface is acquired by deploying a flexible grid sensor array, and a deformation gradient topological graph is constructed to identify an instability risk area. And a dynamic fluid network model of the hydraulic system is established, fluid-solid coupling simulation is carried out in combination with deformation characteristics, and pressure pulsation transmission paths under different control instructions are predicted. And the system dynamically optimizes a data sampling strategy and network model parameters according to a prediction path, generates a hydraulic cylinder coordination action instruction subjected to pressure balance verification, and finally drives an execution mechanism to complete turnover operation. According to the scheme, full-field real-time sensing of structural deformation and dynamic coupling prediction control of hydraulic fluid are achieved, and the safety and control precision of the overweight component in the turnover process are improved.

The invention discloses a health state detection method and system for an aircraft hydraulic system, and relates to the field of aerospace engineering, and the method comprises the steps: dividing a multi-modal data flow into an operation parameter subset and an acoustic emission subset, carrying out the preprocessing, respectively extracting features, generating feature vectors, splicing the two feature vectors into a fusion feature vector, and carrying out the recognition of the fusion feature vector; the fusion feature vector code is mapped into a quantum initial state, a quantum annealing model is established, a state characterization result is obtained, a pre-trained deep neural network is used for processing the state characterization result, a health index is calculated, and a structured diagnosis result of the aircraft hydraulic system is obtained; according to the method, a nonlinear coupling relationship among multiple variables is processed by using a quantum annealing technology, state probability distribution of the aircraft hydraulic system is generated through quantum optimization, and potential characteristics of a complex state are captured.

The invention relates to the technical field of hydraulic valves, and discloses a digital hydraulic valve intelligent diagnosis system which comprises a data acquisition module, a data preprocessing and label generation module, a feature fusion module, a classification diagnosis and decision fusion module and a service life prediction and suggestion generation module. Data such as pressure, vibration, displacement, flow and pollution degree of the valve are comprehensively captured through deployment of a multi-source sensor array at key positions of the digital hydraulic valve and a self-adaptive acquisition strategy, early fault feature omission is avoided, then through preprocessing means such as soft-hard hybrid wavelet threshold denoising and multi-sensor time alignment, the data precision is effectively improved, and the accuracy of the data is improved. Then, through dynamic-static layered feature fusion and an attention weighting mechanism based on GRU, different feature advantages under steady-state and fault working conditions are fully combined, the fault feature distinction degree is greatly enhanced, and the problem that similar faults are likely to be confused is solved.

The invention relates to the technical field of engineering machinery, and particularly discloses an electrically-driven metering pump load-sensitive system, a control method and engineering machinery, the electrically-driven metering pump load-sensitive system comprises a control unit, a driving motor assembly, a metering pump, a pilot hydraulic control unit, a pilot handle assembly, a load-sensitive valve assembly, an actuator assembly, a sensor assembly and a pressure difference control module; the driving motor drives the metering pump to supply oil to the load-sensitive valve assembly so as to drive the actuator assembly to operate; the control unit receives the maximum outlet pressure and the maximum load pressure of the pump collected by the pressure sensor, receives a system target pressure difference signal of the pressure difference control module at the same time, and synchronously controls the rotating speed of the motor and the valve target pressure difference output by the proportional pressure reducing valve. The system aims to solve the problems that a traditional upstream compensation load sensitive system lacks a flow saturation resisting function, and a downstream compensation load sensitive system has extra reversing energy consumption and fixed system pressure difference setting.

The utility model discloses a hydraulic walking control system and a high-altitude operation vehicle. The system comprises a walking pump, a first flow distributing and collecting valve, a second flow distributing and collecting valve and walking motors. A port A of the walking pump is connected with a third port of the first flow distributing and collecting valve and a third port of the second flow distributing and collecting valve, and a port B of the walking pump is connected with a port B of the left front walking motor, a port B of the left rear walking motor, a port A of the right front walking motor and a port A of the right rear walking motor. A fourth port of the first flow distributing and collecting valve is connected with a port A of a left front walking motor, and a second port of the first flow distributing and collecting valve is connected with a port A of a left rear walking motor; a fourth port of the second flow distributing and collecting valve is connected with a port B of the right front walking motor, and a second port of the second flow distributing and collecting valve is connected with a port B of the right rear walking motor. According to the utility model, the problem that the walking effect is influenced due to the change of flow and pressure caused by slipping during walking is avoided.

The invention discloses a double-acting integrated hydraulic nut and a hydraulic nut system. The double-acting integrated hydraulic nut comprises a cylinder body, a piston, a cylinder cover, a locking nut, an outer hexagon head bolt and a locking sleeve. A mounting plane attached to a workpiece is arranged at the bottom of the cylinder body, and the piston is arranged in an inner cavity of the cylinder body in an axial sliding mode. The outer hexagonal head bolt sequentially penetrates through the axial through hole of the piston and the bottom of the cylinder body, and the threaded end of the outer hexagonal head bolt is meshed with a workpiece in a threaded mode. The cylinder cover is arranged at the top of the cylinder body; the locking nut is in threaded connection with the piston rod and is in contact with the top surface of the cylinder cover; a pressurizing oil port connected with a hydraulic pump station is formed in the side wall of the cylinder body. The hexagonal head of the outer hexagonal head bolt is sleeved with the locking sleeve which is in driving connection with the electric wrench. Due to the fact that the bearing seat bolts are compact in layout and large in bolt pre-tightening force requirement, the experiment platform can be rapidly mounted and dismounted, and working time and cost are greatly reduced.

A mobile hydraulic system includes a plurality of hydraulic units which are equipped with at least one hydraulic component and an electronic unit. The respective electronic units are configured to record operating data of the at least one hydraulic component of the respective hydraulic units. Each hydraulic unit has a wireless communication device, wherein the wireless communication devices of the respective hydraulic units are connected to each other in a common wireless network, preferably in a mesh network. The wireless communication devices are configured for wireless transmission of the recorded operating data of the hydraulic units in the wireless network.

The invention relates to the technical field of data processing, in particular to a PSU pressurization module and a control method thereof, and the PSU pressurization module comprises a data acquisition unit, a dynamic compensation unit, a cooperative control unit, a pressure closed-loop unit and an emergency response unit. The data acquisition unit is used for acquiring an energy accumulator pressure value, an environment temperature value and a braking command signal in real time; the dynamic compensation unit generates a viscosity compensation coefficient through a temperature and viscosity mapping table, and compares the viscosity compensation coefficient with the pressure value to generate a pressure deviation value and a deviation trigger threshold value; the cooperative control unit activates the hydraulic pump based on the pressure deviation value and adjusts the start-stop frequency in combination with the viscosity compensation coefficient; the pressure closed-loop unit adopts double electromagnetic valves to alternately release and supplement oil to inhibit pressure fluctuation; the emergency response unit activates the hydraulic pump and opens the bypass electromagnetic valve to output redundant flow during emergency braking, the technical limitation of an existing hydraulic system in an extreme environment is broken through, and the braking reliability is improved.

The invention discloses a multi-mode hydraulic system for synchronous pushing and splicing shield tunneling track deviation rectification. The multi-mode hydraulic system comprises a shield body, a pushing side hydraulic cylinder, a load side hydraulic cylinder, a counter-force plate and a follow-up supporting device. Six hydraulic cylinders are arranged on the propelling side and evenly distributed on the inner side of the shield body. The loading side is provided with four hydraulic cylinders which are uniformly distributed on the inner side of the shield body; the left sides of the ten hydraulic cylinders are connected with the shield body through hooke joints, and the right sides are connected with the counter-force plate through hooke joints; wherein a passive loading mode is adopted on the loading side; five propulsion system control loops are provided on the propulsion side, namely proportional pressure reducing valve control, proportional overflow valve and proportional speed regulating valve parallel control, proportional pressure reducing valve and proportional speed regulating valve load port independent control, proportional overflow valve and proportional speed regulating valve load port independent control and proportional speed regulating valve load port independent control. By the adoption of the technical scheme, various control requirements of pressure control and pressure flow compound control can be met.

The invention relates to the technical field of cubic hydraulic press monitoring, in particular to a cubic hydraulic press health monitoring method and system based on an intelligent sensor, and the system comprises a health monitoring terminal, a data sensing module, a data processing module, a health diagnosis module, a fault management module, a diagnosis positioning module, a cooperative influence module and a rear-end execution module. According to the method, the time domain, the frequency domain and the time domain-frequency domain combined features are extracted, meanwhile, the state change slope is quantified, early warning of the equipment degradation trend is achieved, a fault type-abnormal feature-weight mapping table is constructed, a fault core component and the specific position are accurately positioned, and the fault core component is accurately determined by matching with digital twinborn visual marks. And meanwhile, the internal relation between components is quantified by constructing a component incidence matrix, the health influence coefficient of the cooperative component is calculated in combination with a fault grade coefficient, key components affected by faults are recognized in advance, a cooperative damage list is formed, and operation and maintenance personnel are assisted to intervene in advance.

The utility model provides an open-loop controlled multifunctional hydraulic pulse test bench, which comprises a storage oil tank, an oil supply pump machine, a reversing valve, a pressurizing oil cylinder and an oil supplementing overflow valve, according to the test bed, a large amount of oil flows into a system at the moment that an oil way is opened by a reversing valve, and due to the fact that an overflow valve has a lag phenomenon in response, oil pressure instantaneously generates an overshoot peak value, pressure in a pipeline rapidly rises and a pressure peak appears, then the overflow valve is conducted, the oil is guided out along the overflow valve, and the pressure in the system is reduced to the set pressure of the overflow valve; water hammer waves and rectangular waves of various waveforms and frequency bands can be generated by adjusting the diameter of a variable damping hole of the one-way throttle valve and the rotating speed of the motor, so that the hydraulic pulse test bed can form hydraulic pulse waveforms of various waveforms and frequency bands; the set pressure of the overflow valve is increased, meanwhile, the travel switch loses efficacy, and when the reversing valve is located at the right position all the time, a damage test can be conducted on the hydraulic pipeline to measure the maximum pressure value capable of being borne by a tested piece.

The invention provides a hydraulic motor working state detection method and device and a storage medium, and relates to the technical field of fault detection.The method comprises the steps that a sensor cluster is arranged at key nodes of a hydraulic motor, and a multi-dimensional monitoring data set is constructed; calculating displacement data of a hydraulic motor and kinematic viscosity data of hydraulic oil according to the multi-dimensional monitoring data set to obtain a global monitoring data set; the actual leakage amount of the hydraulic motor is calculated based on the global monitoring data set, and an operation mode switching instruction is generated; receiving the load monitoring instruction or the shutdown maintenance instruction, starting multi-mode fault diagnosis, and obtaining a fault cause set of the hydraulic motor by using a Bayesian network model; and determining a maintenance scheme according to the fault cause set of the hydraulic motor. The technical problems that in the prior art, hysteresis exists, effective preventive detection measures are lacked, potential problems possibly existing in a hydraulic motor cannot be found in time, the maintenance cost is high, and the equipment recovery difficulty is large are solved.

The invention provides an oil level monitoring and leakage early warning system for a hydraulic system of a dredger, which relates to the technical field of hydraulic system monitoring and comprises a hydraulic oil tank, an actuating mechanism assembly connected with the hydraulic oil tank through a pipeline, a data processing unit, a multi-source sensing module, an early warning module and a control module, the multi-source sensing module comprises an integrated liquid level sensor, an actuating mechanism displacement sensor group, an attitude sensor and a temperature sensor, and is used for collecting hydraulic oil level, displacement of each actuating mechanism, ship trim / heeling angle and oil temperature data in real time; the dynamic compensation calculation module is connected with the data processing unit; and the intelligent early warning module is connected with the data processing unit. Normal change and leakage can be distinguished by calculating the oil level change caused by the action of the executing mechanism and the posture of the ship, early warning is conducted in time, pollution and economic losses are prevented, and the situation that when workers inject hydraulic oil, the hydraulic oil splashes, bubbles are generated, and a hydraulic element is damaged can be prevented.

The invention provides a three-order hydraulic servo position control system active-disturbance-rejection control method based on friction compensation, and relates to the technical field of fluid transmission and control, and the method comprises the steps: S1, building a state space model of a three-order hydraulic servo position control system, building a linear expansion state observer, and obtaining a linear active-disturbance-rejection controller of the three-order hydraulic servo position control system; s2, nonlinear time-varying disturbance compensated by the third-order hydraulic servo position control system is converted into a tracking error compensation item controlled by a friction compensation algorithm; s3, verifying the stability of the closed-loop third-order hydraulic servo bit control system through error convergence before and after feed-forward compensation; and S4, the control voltage of the third-order hydraulic servo position control system is input, and nonlinear friction feedforward compensation control of the third-order hydraulic servo position control system is achieved. According to the method, a model-free control strategy is adopted, an innovative solution path is provided for friction suppression and self-adaptive friction compensation, and the control precision and robustness of the hydraulic servo system are improved.

A hydraulic motor output shaft vibration detection device disclosed by the present invention is characterized in that a limiting piece and a driving piece are sequentially installed in a detection box from top to bottom, a memory pointer is installed on the limiting piece, a main pointer is installed on the driving piece, and a contact rod is installed at the lower end of the detection box in an up-down sliding manner; the upper end of the contact rod extends into the detection box and is connected with the driving part, a limiting structure used for limiting the limiting part is installed in the detection box, an unlocking part is installed on the surface of the rear side of the detection box, and the limiting structure is in sliding connection with the unlocking part. The memory pointer is connected with the limiting structure through the limiting piece, the main pointer can detect the corresponding amplitude when the output shaft of the hydraulic motor rotates in real time, the memory pointer can record the maximum amplitude when the output shaft of the hydraulic motor rotates, instant recording of the amplitude is facilitated, and a recorder can clearly see the current vibration value and the maximum peak value at a glance.

The invention discloses a system and method for testing flow, displacement and hydraulic power of a main valve element. The system comprises two displacement sensors, a tested balance valve and a hydraulic testing assembly. A main valve core and a pilot valve core of the tested balance valve are coaxially and oppositely arranged; the two displacement sensors are coaxially fixed with the main valve core and the control piston respectively; the hydraulic test assembly detects the pressure of an oil return port A, a load oil port B, a feedback spring cavity pressure measuring port Pc and a pilot oil inlet X through pressure sensors; the load pressure, the pilot pressure and the oil return back pressure are controlled through a main load oil way, a pilot control oil way and an oil return back pressure oil way respectively, and meanwhile the flow of the oil return is measured through a flow meter. According to the invention, the flow, displacement and hydraulic force of the main valve core under different working conditions can be synchronously and dynamically measured.

The invention relates to the technical field of valve testing, and discloses a changing and washing valve testing device which comprises a testing table, a partition plate is fixedly connected to the bottom of the testing table, a conveying pump is fixedly connected to the right side of the partition plate, a sliding rail is fixedly connected to the top of the testing table, and two fixing clamps are slidably connected to the surface of the sliding rail. The two fixing clamps are both used for fixing a replacement and washing valve, sliding blocks are arranged on the opposite sides of the two fixing clamps, a conveying pipe is fixedly arranged at the output end of the conveying pump, a liquid storage tank is fixedly connected to the left side of the partition plate, and a backflow pipe is fixedly connected to the left side of the liquid storage tank. The two pressure regulating valves can be independently regulated, various actual working conditions and generated different pressure conditions can be simulated, the test requirements of various types of changing and washing valves can be met, the performance of the changing and washing valves under different conditions can be accurately evaluated, and the test environment is closer to the actual working scene, so that potential problems and defects can be found in time, the system fault risk is reduced, and the test efficiency is improved. And the product quality and reliability are improved.