Hydraulic system power balance optimization design method and system

Abstract

The invention provides a hydraulic system power balance optimization design method and system, and relates to the technical field of hydraulic systems.The method comprises the steps that sensors are arranged to collect real-time data and historical load data of a hydraulic pump, a motor and a hydraulic cylinder; then, analyzing historical load data by using a linear regression model to construct a load prediction model, and providing accurate prediction for the load demand at the next moment; then, the efficiency of the hydraulic system and the motor is calculated according to the prediction result and real-time data, and power distribution is conducted according to the load requirement; finally, comprehensive safety monitoring indexes are calculated by analyzing data such as pressure, flow and temperature of the hydraulic system, so that the system state is judged, and corresponding maintenance measures are implemented. The method not only optimizes the power distribution, but also enhances the safety and reliability of the hydraulic system, and has a wide application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulic systems, and in particular to a hydraulic system power balance optimization design method and system. Background Art

[0002] The hydraulic system is a mechanical system that uses liquid to transmit power and control. It is widely used in industries such as industry, agriculture, and construction. Its basic principle is based on the Pascal principle, that is, the change in pressure of the liquid in a closed system will be evenly transmitted. It is mainly composed of hydraulic pumps, hydraulic cylinders, valves, oil tanks, and pipelines. The hydraulic system is efficient, reliable, and adjustable. It can achieve high power output in a small space and has good speed regulation performance. With the advancement of science and technology, modern hydraulic systems are developing in the direction of intelligence and energy saving, and more and more sensors and control algorithms are integrated to achieve automatic control and real-time monitoring, improve safety and efficiency. At the same time, the environmental protection and management of hydraulic oil have also become important design considerations to reduce the impact on the environment. Therefore, hydraulic systems play an important role in modern industry.

[0003] When operating, traditional hydraulic systems often find it difficult to achieve optimal power configuration, which may lead to energy waste or system overload. Therefore, researchers have gradually begun to focus on how to dynamically optimize the power of hydraulic systems through data collection and analysis, load prediction, and intelligent control. By real-time monitoring of the system's operating status and load changes, it is possible to achieve precise control of major components such as hydraulic pumps, motors, and hydraulic cylinders, ensuring that available energy is maximized while meeting work requirements. In addition, with the increasing awareness of environmental protection, energy-saving and environmentally friendly design of hydraulic systems has become an important issue. Power balance optimization can not only reduce energy consumption, but also reduce hydraulic oil emissions and system failure rates, thereby extending equipment life and reducing maintenance costs. These factors make power balance optimization of hydraulic systems increasingly important in modern industry and have broad application prospects.

[0004] The prior art has the following deficiencies:

[0005] Existing hydraulic systems have certain deficiencies in power management and energy efficiency optimization, mainly reflected in the lack of response to dynamic load changes and low energy utilization efficiency. In traditional systems, the output of hydraulic pumps is often fixed and cannot be flexibly adjusted according to actual needs, which leads to serious energy waste under light load conditions and may not be able to provide the required power in time when the load increases suddenly. In addition, traditional hydraulic systems have weak monitoring capabilities for faults and abnormal conditions, and cannot detect problems in a timely manner, which easily leads to increased equipment wear and frequent failures.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute the prior art that is already known to one of ordinary skill in the art. Summary of the invention

[0007] The purpose of the present invention is to provide a hydraulic system power balance optimization design method and system to solve the problems raised in the above background technology.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] A hydraulic system power balance optimization design method, the specific steps include:

[0010] Step 1: Arrange relevant sensors in the hydraulic system to collect the hydraulic pump data, motor-related data, hydraulic cylinder inflow flow and load data at the current moment, and obtain historical load data at multiple moments in the past. The hydraulic pump data includes the input torque, speed and displacement of the hydraulic pump, the motor-related data includes the motor angular velocity, input voltage, input current and power factor, and the load data includes load demand, load force and hydraulic cylinder speed;

[0011] Step 2: Use the linear regression model to build a load forecasting model, and use the historical load data of the previous moment as input and the historical load demand of the next moment as output to train the load forecasting model;

[0012] Step 3: Input the current load data into the trained load prediction model to obtain the load demand at the next moment, calculate the hydraulic system efficiency and motor efficiency, and distribute power according to the load demand;

[0013] Step 4: Analyze the pressure, flow, temperature, efficiency and power data of the hydraulic system, and calculate the comprehensive safety monitoring indicators of the system to determine the current system status.

[0014] Furthermore, the specific logic for collecting data related to hydraulic pumps, motors, and hydraulic cylinders is as follows:

[0015] A torque sensor is installed on the hydraulic pump drive shaft to collect the input torque of the hydraulic pump. A rotary encoder is installed at the rear end of the servo motor to collect the motor angular velocity. A voltage sensor, a current sensor and a power factor meter are installed at the motor input end to collect the motor input voltage, input current and power factor. A speed sensor is installed on the motor output shaft to collect the speed of the hydraulic pump and record the displacement of the hydraulic pump. A temperature sensor is installed inside the oil tank to collect the temperature of the hydraulic oil. Pressure sensors are arranged on the oil inlet pipeline of the rodless chamber of the hydraulic cylinder and the oil return pipeline of the rod chamber of the hydraulic cylinder to collect the pressure of the rod chamber and the pressure of the rodless chamber, and record the effective area of ​​the rod chamber piston and the rodless chamber piston. The formula for calculating the load force is:

[0016] F=p1·A1-p2·A2

[0017] Wherein, F is the load force of the hydraulic cylinder, p1 is the pressure of the rod chamber, p2 is the pressure of the rodless chamber, A1 is the effective area of ​​the piston in the rod chamber, and A2 is the effective area of ​​the piston in the rodless chamber;

[0018] A flow sensor is installed at the inlet of the hydraulic cylinder's oil outlet pipeline to collect the inflow flow of the hydraulic cylinder and record the effective area of ​​the rodless end of the hydraulic cylinder. The formula for calculating the hydraulic cylinder speed is:

[0019]

[0020] Among them, v is the speed of the hydraulic cylinder, that is, the linear motion speed of the hydraulic cylinder piston rod, Q is the inlet flow rate of the hydraulic cylinder, and A is the effective area of ​​the rodless end of the hydraulic cylinder.

[0021] Furthermore, the specific logic for building the load prediction model is as follows:

[0022] The historical load data is divided into a training set and a test set with a ratio of 7:3. The linear regression model is selected to build a load prediction model. The historical load data of the previous moment in the training set is used as input, and the historical load demand of the next moment is used as a label to train the linear regression model. After the training is completed, the test set is input into the trained load prediction model for testing. The root mean square error and the mean absolute error are selected as the loss function. When the change range of the loss function value in five consecutive trainings is less than 0.1, it indicates that the load prediction model training is completed. The model is expressed as follows:

[0023] P d (t+Δt)=α1·F(t)+α2·v(t)+α3·P d (t)

[0024] Among them, P d(t+Δt) represents the load demand at time t+Δt, Δt is the time interval between adjacent moments, F(t) represents the load force at time t, v(t) represents the speed of the hydraulic cylinder at time t, P d (t) represents the load demand at time t, α1, α2, and α3 are regression coefficients, which are obtained by training based on historical load data.

[0025] Furthermore, the specific logic for power distribution according to load demand is:

[0026] The specific logic for calculating the efficiency of the hydraulic system is:

[0027]

[0028] Among them, η v is the volumetric efficiency, is the theoretical output flow of the hydraulic pump, D p is the displacement of the hydraulic pump, n is the speed of the hydraulic pump;

[0029] Δp=|p1-p2|

[0030] Among them, η m is the mechanical efficiency, T is the input torque of the hydraulic pump, is the theoretical input torque of the hydraulic pump, Δp represents the working pressure of the hydraulic system;

[0031] η h =η v ·η m

[0032] Among them, η h The efficiency of the hydraulic system;

[0033] The formula for calculating motor efficiency is:

[0034]

[0035] Among them, η e is the motor efficiency, ω is the motor angular velocity, U is the motor input voltage, I is the motor input current, and cosφ is the power factor;

[0036] The power factor is calculated based on the hydraulic system efficiency and motor efficiency. The calculation formula is as follows:

[0037]

[0038] Among them, θ is the distribution power factor;

[0039] The power allocated to the hydraulic system and the motor system is:

[0040] Ph =θ·P d ,P e =(1-θ)·P d

[0041] Among them, P h is the power allocated to the hydraulic system, P e is the power allocated to the motor system, P d is the load demand at the next moment predicted based on the current moment;

[0042] And follow the following rules when allocating power: when η h >η e When η e >η h When P h >P h,max , the excess will be allocated to the motor system, P h,max is the maximum output power of the hydraulic system. e >P e,max , the excess will be allocated to the hydraulic system, P e,max is the maximum output power of the motor system.

[0043] Furthermore, the specific logic on which the comprehensive safety monitoring indicators of the computing system are based is:

[0044] The formula for obtaining comprehensive safety monitoring indicators is:

[0045] I=β1·I P +β2·I Q +β3·I W +β4·I η +β5·I λ

[0046] Among them, I is the comprehensive safety monitoring index, I P is the pressure sub-index, I Q is the inflow flow sub-index, I W is the temperature sub-index, I η is the efficiency sub-index, I λ is the power sub-index, β1, β2, β3, β4, and β5 are the weights of each single index, 0<β5<β4=β3=β2<β1<1, and β1+β2+β3+β4+β5=1;

[0047] The formula for obtaining the pressure sub-indicator is:

[0048]

[0049] Among them, P minis the minimum value of the pressure safety range, P max It is the maximum value of the pressure safety range;

[0050] The formula for obtaining the inflow flow sub-index is:

[0051]

[0052] Among them, Q rated is the design rated flow rate;

[0053] The formula for obtaining the temperature sub-index is:

[0054]

[0055] Where W is the actual temperature of the hydraulic oil, W min is the minimum value of the temperature safety range, W max It is the maximum value of the temperature safety range;

[0056] The formula for obtaining the efficiency sub-index is:

[0057] η=η h ·η e

[0058] Among them, η represents the actual efficiency of the system, η rated is the lower limit of design efficiency;

[0059] The formula for obtaining the power sub-index is:

[0060] Δλ=λ in -λ out

[0061] λ in =T·n,λ out =Q·p2·η h

[0062] Where Δλ represents the power loss, λ in is the input power of the hydraulic pump, λ out is the output power of the hydraulic pump;

[0063] Compare the comprehensive safety monitoring indicators with the preset indicator status to determine the current status of the hydraulic system, execute corresponding maintenance measures, and issue a danger warning when the hydraulic system is in a dangerous state.

[0064] The present invention further provides a hydraulic system power balance optimization design system, which is used to implement the above-mentioned hydraulic system power balance optimization design method, and includes:

[0065] A data acquisition module is used to arrange relevant sensors in the hydraulic system, collect hydraulic pump data, motor-related data, hydraulic cylinder inflow flow and load data at the current moment, and obtain historical load data at multiple moments in the past, wherein the hydraulic pump data includes the input torque, speed and displacement of the hydraulic pump, the motor-related data includes the motor angular velocity, input voltage, input current and power factor, and the load data includes load demand, load force and hydraulic cylinder speed;

[0066] A load prediction model building module is used to build a load prediction model using a linear regression model, and use the historical load data of the previous moment as input and the historical load demand of the next moment as output to train the load prediction model;

[0067] The power distribution module is used to input the current load data into the trained load prediction model, obtain the load demand at the next moment, calculate the hydraulic system efficiency and motor efficiency, and distribute power according to the load demand;

[0068] The comprehensive safety monitoring and analysis module is used to analyze the pressure, flow, temperature, efficiency and power data of the hydraulic system, calculate the comprehensive safety monitoring indicators of the system, and judge the current system status.

[0069] In the above technical solution, the technical effects and advantages provided by the present invention are:

[0070] By integrating advanced sensors and real-time data acquisition technology, the system can monitor the operating status and load changes of each component in real time. This real-time monitoring capability enables the intelligent control system to respond quickly and dynamically adjust the output power of the hydraulic pump, thereby achieving effective and balanced distribution of system power. In addition, the intelligent control strategy can also optimize the working cycle of the hydraulic system through algorithms to reduce energy consumption during operation. By analyzing historical data and real-time feedback, the system can predict future load changes and adjust the corresponding working parameters in advance. Compared with traditional hydraulic systems, the application of intelligent control can effectively reduce energy loss during operation and reduce the overall energy consumption cost of the system. Another significant advantage is that the intelligent control strategy can extend the service life of the hydraulic system. By optimizing power distribution and reducing unnecessary pressure fluctuations, the wear and failure rate of the system are significantly reduced, and maintenance costs are also reduced. This design approach not only improves the reliability of the system, but also enhances its adaptability under complex working conditions, allowing the hydraulic system to maintain efficient and stable operation in various application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1 It is a schematic diagram of the overall method flow of the present invention;

[0072] Figure 2 Schematic diagram of the system structure of the present invention. DETAILED DESCRIPTION

[0073] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0074] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0075] Example:

[0076] See also Figure 1 , the present invention provides a technical solution:

[0077] A hydraulic system power balance optimization design method, the specific steps include:

[0078] Step 1: Arrange relevant sensors in the hydraulic system to collect the hydraulic pump data, motor-related data, hydraulic cylinder inflow flow and load data at the current moment, and obtain historical load data at multiple moments in the past at equal time intervals. The hydraulic pump data includes the input torque, speed and displacement of the hydraulic pump, the motor-related data includes the motor angular velocity, input voltage, input current and power factor, and the load data includes load demand, load force and hydraulic cylinder speed;

[0079] In this embodiment, the specific logic for collecting data related to the hydraulic pump, motor, and hydraulic cylinder is as follows:

[0080] A torque sensor is installed on the hydraulic pump drive shaft to collect the input torque of the hydraulic pump. A rotary encoder is installed at the rear end of the servo motor to collect the motor angular velocity. A voltage sensor, a current sensor and a power factor meter are installed at the motor input end to collect the motor input voltage, input current and power factor. A speed sensor is installed on the motor output shaft to collect the speed of the hydraulic pump and record the displacement of the hydraulic pump. A temperature sensor is installed inside the oil tank to collect the temperature of the hydraulic oil. Pressure sensors are arranged on the oil inlet pipeline of the rodless chamber of the hydraulic cylinder and the oil return pipeline of the rod chamber of the hydraulic cylinder to collect the pressure of the rod chamber and the pressure of the rodless chamber, and record the effective area of ​​the rod chamber piston and the rodless chamber piston. The formula for calculating the load force is:

[0081] F=p1·A1-p2·A2

[0082] Among them, F is the load force of the hydraulic cylinder, p1 is the pressure of the rod chamber, p2 is the pressure of the rodless chamber, A1 is the effective area of ​​the rod chamber piston, A2 is the effective area of ​​the rodless chamber piston, if F>0, it means that the hydraulic cylinder is outputting thrust, if F<0, it means that the hydraulic cylinder is outputting pulling force;

[0083] A flow sensor is installed at the inlet of the hydraulic cylinder's oil outlet pipeline to collect the inflow flow of the hydraulic cylinder and record the effective area of ​​the rodless end of the hydraulic cylinder. The formula for calculating the hydraulic cylinder speed is:

[0084]

[0085] Among them, v is the speed of the hydraulic cylinder, that is, the linear motion speed of the hydraulic cylinder piston rod, Q is the inlet flow rate of the hydraulic cylinder, and A is the effective area of ​​the rodless end of the hydraulic cylinder.

[0086] The arrangement of multiple sensors on key components such as hydraulic pumps, motors and hydraulic cylinders can comprehensively and real-time collect various data of system operation. This data collection method not only covers important parameters of hydraulic pumps such as input torque, speed and displacement, but also includes information such as motor voltage, current, power factor, and key indicators such as inflow flow, pressure and speed of hydraulic cylinders. This comprehensive data collection can provide a solid foundation for subsequent analysis and optimization, ensuring a comprehensive understanding of the status of the hydraulic system. This step can effectively support the application of intelligent control strategies. Through the collection and analysis of real-time data, the system can dynamically adjust and timely optimize the power output of hydraulic pumps and motors, avoid energy waste, and improve overall energy efficiency. This method can not only reduce operating costs, but also extend the service life of equipment and increase system reliability and stability.

[0087] Step 2: Use the linear regression model to build a load forecasting model, and use the historical load data of the previous moment as input and the historical load demand of the next moment as output to train the load forecasting model;

[0088] In this embodiment, the specific logic for constructing the load prediction model is:

[0089] The historical load data is divided into a training set and a test set with a ratio of 7:3. The linear regression model is selected to build a load prediction model. The historical load data of the previous moment in the training set is used as input, and the historical load demand of the next moment is used as a label to train the linear regression model. After the training is completed, the test set is input into the trained load prediction model for testing. The root mean square error and the mean absolute error are selected as the loss function. When the change range of the loss function value in five consecutive trainings is less than 0.1, it indicates that the load prediction model training is completed. The model is expressed as follows:

[0090] P d (t+Δt)=α1·F(t)+α2·v(t)+α3·P d (t)

[0091] Among them, P d (t+Δt) represents the load demand at time t+Δt, Δt is the time interval between adjacent moments, F(t) represents the load force at time t, v(t) represents the speed of the hydraulic cylinder at time t, P d (t) represents the load demand at time t, α1, α2, and α3 are regression coefficients, which are obtained by training based on historical load data.

[0092] The load demand reflects the power required by the hydraulic system to meet the motion state of the actuator during the current operation. Combining the historical load data of the hydraulic cylinder with the real-time load demand and using a linear regression model to predict the load can effectively capture the changing trend of the system load. This method not only utilizes the continuity and correlation of historical data, but also provides a scientific basis for the prediction of future load demand, thereby achieving dynamic adjustment and optimization control. By dividing the training set and the test set, it can ensure that the model effectively learns the law of load change during the training process, and the generalization ability of the model is evaluated through the test set. In addition, by selecting the root mean square error and the mean absolute error as the loss function, the accuracy of the model prediction can be quantified, thereby providing a clear goal for model optimization. When the change range of the loss function value in five consecutive trainings is less than 0.1, it indicates the stability and effectiveness of the model, ensuring the credibility of the prediction results.

[0093] Step 3: Collect the current load data and load demand, input them into the trained load prediction model, obtain the model's prediction of the load demand at the next moment, calculate the hydraulic system efficiency and motor efficiency, and distribute power according to the load demand;

[0094] In this embodiment, the specific logic for power distribution according to load demand is:

[0095] The specific logic for calculating the efficiency of the hydraulic system is:

[0096]

[0097] Among them, η v is the volumetric efficiency, is the theoretical output flow of the hydraulic pump, D p is the displacement of the hydraulic pump, n is the speed of the hydraulic pump;

[0098] Δp=|p1-p2|

[0099] Among them, η m is the mechanical efficiency, t is the input torque of the hydraulic pump, is the theoretical input torque of the hydraulic pump, Δp represents the working pressure of the hydraulic system;

[0100] η h =η v ·η m

[0101] Among them, η h The efficiency of the hydraulic system;

[0102] The formula for calculating motor efficiency is:

[0103]

[0104] Among them, η e is the motor efficiency, ω is the motor angular velocity, U is the motor input voltage, I is the motor input current, and cosφ is the power factor;

[0105] The power factor is calculated based on the hydraulic system efficiency and motor efficiency. The calculation formula is as follows:

[0106]

[0107] Among them, θ is the distribution power factor;

[0108] The power allocated to the hydraulic system and the motor system is:

[0109] P h =θ·P d ,P e =(1-θ)·P d

[0110] Among them, P h is the power allocated to the hydraulic system, P e is the power allocated to the motor system, Pd is the load demand at the next moment predicted based on the current moment;

[0111] And follow the following rules when allocating power: when η h >η e When η e >η h When P h >P h,max , the excess will be allocated to the motor system, P h,max is the maximum output power of the hydraulic system. e >P e,max , the excess will be allocated to the hydraulic system, P e,max is the maximum output power of the motor system.

[0112] For different types of hydraulic systems, the maximum output power values ​​are different, for example: small hydraulic systems (such as construction machinery, agricultural machinery): the maximum output power is set to 50kW, medium hydraulic systems (such as industrial equipment, lifting machinery): the maximum output power is set to 200kW, large hydraulic systems (such as ship hydraulic systems, heavy machinery): the maximum output power is set to 1MW; the maximum output power of the voltage system depends on the rated voltage, rated current and design parameters of the power equipment. For different types of power equipment, small power equipment (such as small motors, household appliances): the maximum output power is set to 5kW, industrial motors or equipment (such as processing machine tools, industrial pumps): the maximum output power is set to 500kW, large power equipment (such as generators, transformers): the maximum output power is set to 1000MW;

[0113] By collecting the current load data and load demand, and using the trained load prediction model to obtain the load demand at the next moment, the future state of the system can be effectively predicted. For the hydraulic system, the comprehensive consideration of volumetric efficiency and mechanical efficiency (i.e., the hydraulic system efficiency η h ) enables the system to evaluate its energy conversion capacity under different working conditions, thereby optimizing the coordination of the hydraulic pump and the motor. In the specific implementation of power distribution, the distribution power factor θ calculated based on the hydraulic system efficiency and the motor efficiency ensures that the hydraulic system and the motor system can reasonably distribute power according to their respective efficiency advantages. This dynamic power distribution mechanism effectively avoids the waste of system energy and ensures that each part can work efficiently under different working conditions. For example, when the hydraulic system efficiency is higher than the motor efficiency, the system will give priority to the hydraulic drive, and vice versa. This intelligent scheduling method can maximize the overall efficiency of the system and improve energy utilization. Finally, set the power limitation rules (such as P h and P eThe maximum power limit of the power supply further ensures the safety and stability of the system during operation. When the power of a system exceeds the set maximum value, the excess will be allocated to another system first, ensuring that the load of each part is within a reasonable range and avoiding the risk of overload or damage.

[0114] Step 4: Analyze the pressure, flow, temperature, efficiency and power data of the hydraulic system, and calculate the comprehensive safety monitoring indicators of the system to determine the current system status;

[0115] In this embodiment, the specific logic based on which the comprehensive safety monitoring index of the computing system is calculated is:

[0116] The formula for obtaining comprehensive safety monitoring indicators is:

[0117] I=β1·I P +β2·I Q +β3·I W +β4·I η +β5·I λ

[0118] Among them, I is the comprehensive safety monitoring index, I P is the pressure sub-index, U Q is the inflow flow sub-index, I W is the temperature sub-index, I η is the efficiency sub-index, I λ is the power sub-index, β1, β2, β3, β4, and β5 are the weights of each single index, 0<β5<β4=β3=β2<β1<1, and β1+β2+β3+β4+β5=1, β1=0.3, β2=β3=β4=0.2, β5=0.1 can be set;

[0119] The formula for obtaining the pressure sub-indicator is:

[0120]

[0121] Among them, P min is the minimum value of the pressure safety range, set to 10MPa, P max The maximum value of the pressure safety range is set to 25MPa;

[0122] The formula for obtaining the inflow flow sub-index is:

[0123]

[0124] Among them, Q rated For the design rated flow rate, set it to 100L / min;

[0125] The formula for obtaining the temperature sub-index is:

[0126]

[0127] Where W is the actual temperature of the hydraulic oil, W min The minimum temperature safety range is set to 30°C, W max The maximum value of the temperature safety range is set to 60°C;

[0128] The formula for obtaining the efficiency sub-index is:

[0129] η=η h ·η e

[0130] Among them, η represents the actual efficiency of the system, η rated is the lower limit of design efficiency, which is set to 0.9;

[0131] The formula for obtaining the power sub-index is:

[0132] Δλ=λ in -λ out

[0133] λ in =T·n,λ out =Q·p2·η h

[0134] Where Δλ represents the power loss, λ in is the input power of the hydraulic pump, λ out is the output power of the hydraulic pump;

[0135] Compare the comprehensive safety monitoring index with the preset index status. When I>0.9, the system operates completely normally and no intervention is required. When 0.7≤I≤0.9, the system is in a warning state with slight abnormalities. It is recommended to check key parameters. When 0.5≤I≤0.7, the system is in a warning state with obvious abnormalities and requires timely maintenance or adjustment. When I<0.5, the system is in a dangerous state and a danger warning is issued. The system must be shut down immediately and the fault must be eliminated.

[0136] When the pressure Δp is within the safe range (P min ≤Δp≤P max ),I P =1, reflecting the normal state of the system. When the pressure is lower than the minimum value or exceeds the maximum value, I P Gradually decreases, indicating that the system pressure is abnormal and requires attention; when the flow rate Q is less than or equal to the rated flow rate Q rated When Q =1; when the flow exceeds the rated flow, I QIt gradually decreases, indicating the risk caused by excessive flow. When the temperature W is within the safe range, I T =1; when out of range, I T It will decrease, indicating that the system temperature is abnormal and needs to be checked; when the efficiency η is greater than the lower limit of the design efficiency η rated When η =1; if the efficiency is reduced, I η will decrease, indicating that there is a problem with the system efficiency; when the power loss Δλ is greater than or equal to zero, I λ It will decrease as the power loss increases, indicating that the system performance has declined; this formula integrates multiple key performance indicators (pressure, flow, temperature, efficiency and power) into a comprehensive safety monitoring indicator I, which can comprehensively evaluate the operating status of the hydraulic system. This comprehensive analysis helps to discover potential system problems and ensure that the interaction of various factors is fully considered.

[0137] Pressure is a key indicator of hydraulic system, which is directly related to the safety and stability of the system. Too high or too low pressure may lead to equipment failure or accident, so it is reasonable to set its weight to the highest (0.3). This shows that in comprehensive safety monitoring, the state of pressure has the greatest impact on the overall system safety. Flow, temperature and efficiency are important factors affecting the performance of hydraulic system, and all three play an important role in the operation of the system. Giving them the same weight (0.2) reflects the relative importance of these factors to the system performance under normal operating conditions. This setting shows that these indicators have relatively equal attention in the comprehensive evaluation, but are less important than pressure. Although power loss will also affect the efficiency and safety of the system, it has less impact on the direct safety of the system than pressure, flow, temperature and efficiency. Therefore, it is reasonable to give it the lowest weight (0.1). This setting points to the secondary position of power loss in the operation of the system and emphasizes the importance of other indicators in the comprehensive evaluation. The sum of the weights of the five sub-indicators is 1. This constraint ensures that the comprehensive safety monitoring indicator is a normalized indicator, ensuring that the total contribution of the weighted combination of the five factors is 100%.

[0138] See also Figure 2 The present invention further provides a hydraulic system power balance optimization design system, which is used to implement the above-mentioned hydraulic system power balance optimization design method, including:

[0139] A data acquisition module is used to arrange relevant sensors in the hydraulic system, collect hydraulic pump data, motor-related data, hydraulic cylinder inflow flow and load data at the current moment, and obtain historical load data at multiple moments in the past, wherein the hydraulic pump data includes the input torque, speed and displacement of the hydraulic pump, the motor-related data includes the motor angular velocity, input voltage, input current and power factor, and the load data includes load demand, load force and hydraulic cylinder speed;

[0140] A load prediction model building module is used to build a load prediction model using a linear regression model, and use the historical load data of the previous moment as input and the historical load demand of the next moment as output to train the load prediction model;

[0141] The power distribution module is used to input the current load data into the trained load prediction model, obtain the load demand at the next moment, calculate the hydraulic system efficiency and motor efficiency, and distribute power according to the load demand;

[0142] The comprehensive safety monitoring and analysis module is used to analyze the pressure, flow, temperature, efficiency and power data of the hydraulic system, calculate the comprehensive safety monitoring indicators of the system, and judge the current system status.

[0143] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0144] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product. Those skilled in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software methods depends on the specific application and design constraints of the technical solution.

[0145] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0146] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A hydraulic system power balance optimization design method, characterized in that: The specific steps include: Step 1: Arrange relevant sensors in the hydraulic system to collect the hydraulic pump data, motor-related data, hydraulic cylinder inflow flow and load data at the current moment, and obtain historical load data at multiple moments in the past. The hydraulic pump data includes the input torque, speed and displacement of the hydraulic pump, the motor-related data includes the motor angular velocity, input voltage, input current and power factor, and the load data includes load demand, load force and hydraulic cylinder speed; Step 2: Use the linear regression model to build a load forecasting model, and use the historical load data of the previous moment as input and the historical load demand of the next moment as output to train the load forecasting model; Step 3: Input the current load data into the trained load prediction model to obtain the load demand at the next moment, calculate the hydraulic system efficiency and motor efficiency, and distribute power according to the load demand; Step 4: Analyze the pressure, flow, temperature, efficiency and power data of the hydraulic system, and calculate the comprehensive safety monitoring indicators of the system to determine the current system status.

2. A hydraulic system power balance optimization design method according to claim 1, characterized in that: The specific logic for collecting data related to hydraulic pumps, motors, and hydraulic cylinders is as follows: A torque sensor is installed on the hydraulic pump drive shaft to collect the input torque of the hydraulic pump. A rotary encoder is installed at the rear end of the servo motor to collect the motor angular velocity. A voltage sensor, a current sensor and a power factor meter are installed at the motor input end to collect the motor input voltage, input current and power factor. A speed sensor is installed on the motor output shaft to collect the speed of the hydraulic pump and record the displacement of the hydraulic pump. A temperature sensor is installed inside the oil tank to collect the temperature of the hydraulic oil. Pressure sensors are arranged on the oil inlet pipeline of the rodless chamber of the hydraulic cylinder and the oil return pipeline of the rod chamber of the hydraulic cylinder to collect the pressure of the rod chamber and the pressure of the rodless chamber, and record the effective area of ​​the rod chamber piston and the rodless chamber piston. The formula for calculating the load force is: F=p1·A1-p2·A2 Wherein, F is the load force of the hydraulic cylinder, p1 is the pressure of the rod chamber, p2 is the pressure of the rodless chamber, A1 is the effective area of ​​the piston in the rod chamber, and A2 is the effective area of ​​the piston in the rodless chamber; A flow sensor is installed at the inlet of the hydraulic cylinder's oil outlet pipeline to collect the inflow flow of the hydraulic cylinder and record the effective area of ​​the rodless end of the hydraulic cylinder. The formula for calculating the hydraulic cylinder speed is: Among them, v is the speed of the hydraulic cylinder, that is, the linear motion speed of the hydraulic cylinder piston rod, Q is the inlet flow rate of the hydraulic cylinder, and A is the effective area of ​​the rodless end of the hydraulic cylinder.

3. A hydraulic system power balance optimization design method according to claim 2, characterized in that: The specific logic for building the load forecasting model is: The historical load data is divided into a training set and a test set with a ratio of 7:

3. The linear regression model is selected to build a load prediction model. The historical load data of the previous moment in the training set is used as input, and the historical load demand of the next moment is used as a label to train the linear regression model. After the training is completed, the test set is input into the trained load prediction model for testing. The root mean square error and the mean absolute error are selected as the loss function. When the change range of the loss function value in five consecutive trainings is less than 0.1, it indicates that the load prediction model training is completed. The model is expressed as follows: P d (t+Δt)=α1·F(t)+α2·v(t)+α3·P d (t) Among them, P d (t+Δt) represents the load demand at time t+Δt, Δt is the time interval between adjacent moments, F(t) represents the load force at time t, v(t) represents the speed of the hydraulic cylinder at time t, P d (t) represents the load demand at time t, α1, α2, and α3 are regression coefficients, which are obtained by training based on historical load data.

4. A hydraulic system power balance optimization design method according to claim 3, characterized in that: The specific logic for power distribution based on load demand is: The specific logic for calculating the efficiency of the hydraulic system is: Among them, η v is the volumetric efficiency, is the theoretical output flow of the hydraulic pump, D p is the displacement of the hydraulic pump, n is the speed of the hydraulic pump; Among them, η m is the mechanical efficiency, T is the input torque of the hydraulic pump, is the theoretical input torque of the hydraulic pump, Δp represents the working pressure of the hydraulic system; or h =the v ·or m Among them, η h The efficiency of the hydraulic system; The formula used to calculate motor efficiency is: Among them, η e is the motor efficiency, ω is the motor angular velocity, U is the motor input voltage, I is the motor input current, and cosφ is the power factor; The power factor is calculated based on the hydraulic system efficiency and motor efficiency. The calculation formula is as follows: Among them, θ is the distribution power factor; The power allocated to the hydraulic system and the motor system is: P h =θ·P d ,P e =(1-θ)·P d Among them, P h is the power allocated to the hydraulic system, P e is the power allocated to the motor system, P d is the load demand at the next moment predicted based on the current moment; And follow the following rules when allocating power: when η h >η e When η e >η h When P h >P h,max , the excess will be allocated to the motor system, P h,max is the maximum output power of the hydraulic system. e >P e,max , the excess will be allocated to the hydraulic system, P e,max is the maximum output power of the motor system.

5. A hydraulic system power balance optimization design method according to claim 4, characterized in that: The specific logic for calculating the comprehensive safety monitoring indicators of the system is: The formula for obtaining comprehensive safety monitoring indicators is: I=β1·I P +β2·I Q +β3·I W +β4·I η +β5·I λ Among them, I is the comprehensive safety monitoring index, I P is the pressure sub-index, I Q is the inflow flow sub-index, I W is the temperature sub-index, I η is the efficiency sub-index, I λ is the power sub-index, β1, β2, β3, β4, and β5 are the weights of each single index, 0<β5<β4=β3=β2<β1<1, and β1+β2+β3+β4+β5=1; The formula for obtaining the pressure sub-indicator is: Among them, P min is the minimum value of the pressure safety range, P max It is the maximum value of the pressure safety range; The formula for obtaining the inflow flow sub-index is: Among them, Q rated is the design rated flow rate; The formula for obtaining the temperature sub-index is: Where W is the actual temperature of the hydraulic oil, W min is the minimum value of the temperature safety range, W max It is the maximum value of the temperature safety range; The formula for obtaining the efficiency sub-index is: Among them, η represents the actual efficiency of the system, η rated is the lower limit of design efficiency; The formula for obtaining the power sub-index is: l in =T·n,λ out =Q·p2·η h Where Δλ represents the power loss, λ in is the input power of the hydraulic pump, λ out is the output power of the hydraulic pump; Compare the comprehensive safety monitoring indicators with the preset indicator status to determine the current status of the hydraulic system, execute corresponding maintenance measures, and issue a danger warning when the hydraulic system is in a dangerous state.

6. A hydraulic system power balance optimization design system, characterized in that: The hydraulic system power balance optimization design system is used to implement the hydraulic system power balance optimization design method according to any one of claims 1 to 5, comprising: A data acquisition module is used to arrange relevant sensors in the hydraulic system, collect hydraulic pump data, motor-related data, hydraulic cylinder inflow flow and load data at the current moment, and obtain historical load data at multiple moments in the past, wherein the hydraulic pump data includes the input torque, speed and displacement of the hydraulic pump, the motor-related data includes the motor angular velocity, input voltage, input current and power factor, and the load data includes load demand, load force and hydraulic cylinder speed; A load prediction model building module is used to build a load prediction model using a linear regression model, and use the historical load data of the previous moment as input and the historical load demand of the next moment as output to train the load prediction model; The power distribution module is used to input the current load data into the trained load prediction model, obtain the load demand at the next moment, calculate the hydraulic system efficiency and motor efficiency, and distribute power according to the load demand; The comprehensive safety monitoring and analysis module is used to analyze the pressure, flow, temperature, efficiency and power data of the hydraulic system, calculate the comprehensive safety monitoring indicators of the system, and judge the current system status.

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