Propeller system feathering and returning function MATLAB simulation method

Abstract

The invention relates to the technical field of data processing, in particular to a propeller system feathering and returning function MATLAB simulation method which comprises the steps that a hydraulic oil way communication path and structure size parameters of a propeller system are collected; defining an oil path node connection rule based on a communication path, converting a structure size parameter into a pipe diameter constraint condition, and constructing a joint simulation model; positioning an electric signal input port of a propeller pitch controller and injecting a feathering instruction signal group and a propeller return instruction signal group; the execution model simulates a lubricating oil flowing path and outputs a hydraulic oil cavity pressure value, a through-flow section area value and an instantaneous flow value; and a mapping relation table is generated by correlating time sequence change data of the through-flow section area value and the instantaneous flow value, and an air small-distance limiting position correction strategy is formulated. The simulation model is used for replacing a physical prototype for testing, dynamic capture and optimization of the hydraulic flow attenuation characteristic are achieved, and the technical problems that the experiment cost is high, the iteration period is long and transient flow monitoring is difficult are solved.

Description

Technical Field

[0001] This invention relates to the field of data processing technology, and in particular to a MATLAB simulation method for the feathering and swerving functions of a propeller system. Background Technology

[0002] Existing physical prototype-based hydraulic verification methods have the following technical pain points in practical applications: relying on physical prototype testing leads to high experimental costs and lengthy iteration cycles, and it is impossible to capture dynamic flow changes in real time; in the development scenario of propeller systems, when optimizing the hydraulic flow attenuation characteristics of small-distance limiting positions in the air, it is necessary to repeatedly build oil circuit test benches and perform tests, such as adjusting valve positions to alleviate flow attenuation caused by changes in flow area. Each design change requires reprocessing components, consuming lubricating oil resources, and conducting experiments, which prolongs the development cycle and makes it difficult to monitor transient fluctuations in flow in real time, resulting in an inefficient optimization process. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a MATLAB simulation method for the feathering and backfeeding functions of a propeller system. This invention solves the technical problem of inefficient optimization of the hydraulic flow attenuation characteristics of a propeller system in small-distance airborne limited position, which is caused by the reliance on physical prototype testing, resulting in high experimental costs, lengthy iteration cycles, and the inability to capture dynamic flow changes in real time.

[0004] To solve the above-mentioned technical problems, the specific contents of the present invention are as follows:

[0005] The present invention provides a MATLAB simulation method for the feathering and swerving functions of a propeller system, comprising:

[0006] Step 1: Obtain the hydraulic oil circuit connection path and structural dimension parameters of the propeller system;

[0007] Step 2: Define the oil circuit node connection rules according to the connection path, convert the structural size parameters into pipe diameter constraints, and construct a joint simulation model based on the connection rules and pipe diameter constraints;

[0008] Step 3: Locate the electrical signal input port of the pitch controller in the co-simulation model, and inject the feathering command signal group and the revving command signal group into the port;

[0009] Step 4: Perform a joint simulation model to simulate and calculate the flow path of the lubricating oil, and output the hydraulic oil chamber pressure value, flow cross-sectional area value, and instantaneous flow rate value.

[0010] Step 5: Generate a mapping table by associating the time-series change data of the flow cross-sectional area value and the instantaneous flow rate value, and formulate an airborne small-distance limiting position correction strategy using the mapping table.

[0011] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 1 includes:

[0012] The valve displacement switching logic of the pitch controller is read as the reference for hydraulic circuit control;

[0013] Based on the oil circuit control reference, locate the connection path from the speed limiter oil distributor valve to the servo valve, and measure the oil circuit length of this path;

[0014] The interface fit dimensions between the beta tube bushing and the propeller pitch chamber are determined based on the oil circuit length.

[0015] The diameter of the pipe from the output end of the feather pump to the return valve is matched according to the interface adapter size.

[0016] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 2 includes:

[0017] Construct the displacement equation for the ground beta valve and define the oil circuit on / off conditions for releasing the small-distance movement restriction in the air;

[0018] Configure the input range of the propeller pump speed signal port and displacement signal port based on the oil circuit on / off conditions;

[0019] Connect the servo valve current signal to the propeller oil chamber hydraulic feedback node to establish a pressure-displacement conversion mechanism;

[0020] The path selection function for connecting the left position of the return valve to the speed limiter cavity is generated based on the pressure and displacement conversion mechanism.

[0021] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 2 further includes:

[0022] Analyze the oil circuit on / off rules of the ground beta valve in the left position and output the lubricating oil flow direction control command;

[0023] The flow distribution ratio of the return valve in the left position is calculated based on the lubricating oil flow direction control command, and a lubricating oil flow distribution formula is generated.

[0024] Map the flow allocation ratio to the right position of the featherer valve to trigger the straight-through path activation condition;

[0025] By integrating the flow control commands, flow allocation ratios, and direct path activation conditions, a gate group collaborative verification matrix is ​​constructed.

[0026] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 4 includes:

[0027] Activate the high-pressure lubricating oil injection of the feathering pump into the return valve inlet, pushing the lubricating oil into the speed limiter distributor valve;

[0028] In response to the oil pressure increase signal from the oil separator valve, the lubricating oil is driven to flow through the ground beta valve to the servo valve control port;

[0029] Based on the change in the opening of the servo valve control port, lubricating oil is guided into the small-pitch oil chamber of the propeller;

[0030] The pressure difference threshold between the inlet pressure of the small-distance oil chamber and the return pressure of the large-distance oil chamber is detected simultaneously to complete the return oil action of the large-distance oil chamber.

[0031] When the feathering command signal group is loaded:

[0032] Switch the high-pressure lubricating oil from the feather pump to the inlet of the feather valve, directly connecting to the input port of the beta tube bushing;

[0033] Based on the oil load signal of the beta tube bushing, distribute lubricating oil to the large-pitch oil chamber of the propeller;

[0034] The oil inlet rate of the large-distance oil chamber and the oil return rate of the small-distance oil chamber are matched in real time to complete the oil return action of the small-distance oil chamber.

[0035] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 includes:

[0036] Calculate the real-time area change rate of the flow cross section in the variable pitch oil chamber;

[0037] A lubricating oil flow rate decay curve is generated based on the area change rate.

[0038] Extract the peak and trough characteristic values ​​of the lubricating oil flow rate decay curve;

[0039] Correlate the characteristic values ​​with the hydraulic system pressure fluctuation data, and output a propeller displacement time-domain response report.

[0040] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0041] Collect attenuation characteristic data of the propeller blade angular displacement process from 90° to -19°;

[0042] When the flow area shrinks beyond a predetermined threshold, the transient response mode of the attenuation characteristic data is analyzed; the coupling coefficient between lubricating oil viscosity and attenuation rate is calculated based on the transient response mode.

[0043] Establish a mapping relationship between the coupling coefficient and the rate of change of the flow cross section to generate a hydraulic power loss prediction table.

[0044] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0045] Calculate the deviation between the simulated flow attenuation characteristics and the design specifications;

[0046] The flow bottleneck coordinates of the airborne small-distance limited-movement oil circuit section are located based on the deviation value;

[0047] Generate valve position offset and flow cross-section correction coefficient based on flow bottleneck coordinates;

[0048] The offset and correction coefficient are converted into servo valve control current gradient parameters, and a compensation instruction set is output.

[0049] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0050] Import the valve position offset and the flow cross section correction coefficient into the co-simulation model;

[0051] Perform iterative model calculations and collect optimized flow area change rate data;

[0052] Reconstruct the attenuation characteristic curve based on the rate of change data, and calculate the reduction in pitch time.

[0053] When the shortening amount reaches the target range threshold, a hydraulic system characteristic compliance confirmation report is generated.

[0054] Furthermore, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0055] The servo valve control current gradient parameters are applied to the pitch controller electrical signal input port.

[0056] Call the hydraulic power loss prediction table to calculate the compensated lubricating oil viscosity and attenuation coupling coefficient;

[0057] The data acquisition frequency of the flow area change rate is dynamically adjusted based on the coupling coefficient.

[0058] By correlating the propeller displacement time-domain response report with the pitch reduction, a hydraulic system cooperative gain coefficient is generated.

[0059] When the cooperative gain coefficient exceeds a preset threshold, the ultimate correction strategy for small-distance air-to-ground movement is output.

[0060] Beneficial effects of this invention;

[0061] The beneficial effects of this invention are manifested in solving the technical pain point of optimizing the hydraulic flow attenuation characteristics of propeller systems at small distances in the air through the construction of a joint simulation model and a dynamic data analysis mechanism. First, the simulation foundation is constructed by obtaining the hydraulic circuit connection path and structural dimension parameters, eliminating the need for physical prototype processing and lubricating oil resource consumption, directly reducing experimental costs. Second, a joint simulation model is established by defining the connection rules of the circuit nodes and pipe diameter constraints. This integrates the circuit on / off conditions defined by the ground beta valve displacement equation, the servo valve current signal, and the pressure-displacement conversion mechanism of the propeller oil chamber hydraulic feedback node, enabling dynamic simulation calculation of the lubricating oil flow path. This avoids repeatedly building the circuit test bench and significantly shortens the iteration cycle. When executing the model, a group of command signals is injected into the electrical signal input port of the pitch controller, outputting real-time data on the three key elements: hydraulic oil chamber pressure value, flow cross-sectional area value, and instantaneous flow rate value. This accurately captures the transient fluctuation characteristics of flow rate during the flow area reduction process, overcoming the technical limitation of physical testing in real-time monitoring of dynamic flow. A mapping table is generated by correlating the temporal changes of the flow cross-sectional area and instantaneous flow rate. The coordinates of the flow bottleneck at the small-distance air-mounted limiting position are located, and the valve position offset and flow cross-sectional area correction coefficient are generated and converted into servo valve control current gradient parameters. The attenuation characteristic curve is reconstructed through model iteration, and the reduction in pitch time is quantified, forming a data-driven closed-loop optimization path. Finally, the hydraulic power loss prediction table is called to calculate the coupling coefficient between lubricating oil viscosity and attenuation. A synergistic gain coefficient is generated by correlating the propeller displacement time-domain response report with the reduction in pitch time. When the coefficient exceeds a threshold, the ultimate correction strategy is output, locking in the optimal parameter combination and systematically improving the optimization efficiency of hydraulic flow attenuation characteristics. Attached Figure Description

[0062] To more clearly illustrate the technical solution of the present invention, the drawings used in the embodiments will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0063] Figure 1 A flowchart of a MATLAB simulation method for the feathering and revving function of a propeller system provided in an embodiment of the present invention. Detailed Implementation

[0064] To make the technical solution of the present invention clearer, the present invention will be clearly and completely described below with reference to specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. The present invention provided by various embodiments will be described in detail below with reference to the accompanying drawings. To better understand the purpose of the present invention, the present invention will be described in further detail below.

[0065] Please see Figure 1 The present invention provides a MATLAB simulation method for the feathering and swerving functions of a propeller system, comprising:

[0066] Step 1: Obtain the hydraulic oil circuit connection path and structural dimension parameters of the propeller system;

[0067] Step 2: Define the oil circuit node connection rules according to the connection path, convert the structural size parameters into pipe diameter constraints, and construct a joint simulation model based on the connection rules and pipe diameter constraints;

[0068] Step 3: Locate the electrical signal input port of the pitch controller in the co-simulation model, and inject the feathering command signal group and the revving command signal group into the port;

[0069] Step 4: Perform a joint simulation model to simulate and calculate the flow path of the lubricating oil, and output the hydraulic oil chamber pressure value, flow cross-sectional area value, and instantaneous flow rate value.

[0070] Step 5: Generate a mapping table by associating the time-series change data of the flow cross-sectional area value and the instantaneous flow rate value, and formulate an airborne small-distance limiting position correction strategy using the mapping table.

[0071] Obtaining the hydraulic circuit connections of the propeller system specifically involves acquiring the lubricating oil delivery channel from the speed governor's distributor valve to the servo valve, the interface connection path between the beta tube bushing and the propeller pitch chamber, and the pipeline routing from the feathering pump output to the return valve. Structural dimensional parameters include the displacement stroke of the pitch controller valve, the inner diameter of the hydraulic pipelines, and the volume data of the pitch chamber. These parameters form the physical basis for constructing the simulation model.

[0072] Based on the connectivity path obtained in step 1, the oil circuit node connection rules are defined as the hydraulic interaction logic between the speed limiter, feathering pump, pitch controller, and propeller. The pipe inner diameter in the structural dimensional parameters is converted into a pipe diameter constraint condition to limit the boundary range of lubricating oil flow in the simulation model. The co-simulation model integrates the oil circuit node connection rules and the pipe diameter constraint condition to form a mathematical framework that can simulate the dynamic flow of lubricating oil.

[0073] In the co-simulation model, the electrical signal input port of the pitch controller corresponds to the command receiving interface of the actual equipment. The feathering command signal group injected into the port includes a valve actuation command with a voltage of 28VDC, and the revving command signal group includes a valve reset command with a voltage of 0VDC. The signal injection behavior triggers the switching mechanism of the hydraulic circuit in the simulation model.

[0074] When executing the co-simulation model, the simulation calculates the flow state of lubricating oil along the connected path defined in step 1. In the output data, the hydraulic oil chamber pressure value reflects the pressure state of the variable-pitch oil chamber, the flow cross-sectional area value characterizes the flow capacity of key nodes in the oil circuit, and the instantaneous flow rate value records the dynamic changes in the lubricating oil flow rate. These three data constitute the core dataset for hydraulic system characteristic analysis.

[0075] By correlating the time-series changes in the cross-sectional area and instantaneous flow rate, a mapping table is generated to reveal the quantitative correlation between area reduction and flow rate attenuation. This mapping table is used to locate bottleneck areas in the hydraulic circuit at small-distance air-mounted limiting positions, and correction strategies are developed, specifically including adjusting the valve position offset of the pitch controller and optimizing the servo valve control current gradient parameters. The strategy generation process addresses the technical limitation of real-time capture of dynamic flow rates in physical testing.

[0076] Specifically, the MATLAB simulation method for the feathering and revving function of a propeller system according to the present invention includes step 1 as follows:

[0077] The valve displacement switching logic of the pitch controller is read as the reference for hydraulic circuit control;

[0078] Based on the oil circuit control reference, locate the connection path from the speed limiter oil distributor valve to the servo valve, and measure the oil circuit length of this path;

[0079] The interface fit dimensions between the beta tube bushing and the propeller pitch chamber are determined based on the oil circuit length.

[0080] The diameter of the pipe from the output end of the feather pump to the return valve is matched according to the interface adapter size.

[0081] The valve displacement switching logic of the pitch controller is used as the hydraulic circuit control reference, specifically referring to the acquisition of the displacement stroke and switching sequence of the ground beta valve, return valve, and feathering valve. Based on the hydraulic circuit control reference, the connection path from the speed governor's oil distribution valve to the servo valve is located, and the geometric length and bending angle of this path are measured. The lubricating oil flow delay is calculated based on the hydraulic circuit length to determine the interface flange adaptation dimensions between the beta tube bushing and the propeller pitch chamber. The inner diameter of the pipe from the feathering pump output to the return valve is matched according to the interface flange adaptation dimensions to achieve dimensional consistency between the simulation model and the physical system.

[0082] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 2 includes:

[0083] Construct the displacement equation for the ground beta valve and define the oil circuit on / off conditions for releasing the small-distance movement restriction in the air;

[0084] Configure the input range of the propeller pump speed signal port and displacement signal port based on the oil circuit on / off conditions;

[0085] Connect the servo valve current signal to the propeller oil chamber hydraulic feedback node to establish a pressure-displacement conversion mechanism;

[0086] The path selection function for connecting the left position of the return valve to the speed limiter cavity is generated based on the pressure and displacement conversion mechanism.

[0087] When constructing the displacement equation for the ground beta valve, the oil circuit on / off conditions for releasing the small-distance airborne movement restriction are defined, including the mapping relationship between the valve's left-position opening area and the lubricating oil flow coefficient. Based on the oil circuit on / off conditions, the input range of the feathering pump speed signal port is configured to be the rated speed range, and the input range of the displacement signal port is configured to be the maximum displacement percentage. The servo valve current signal is connected to the propeller oil chamber hydraulic feedback node to establish a linear conversion mechanism between pressure value change and propeller displacement. Based on the pressure and displacement conversion mechanism, a path selection function is generated to connect the left-position return valve to the speed limiter cavity; the function output value determines the lubricating oil flow priority.

[0088] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 2 further includes:

[0089] Analyze the oil circuit on / off rules of the ground beta valve in the left position and output the lubricating oil flow direction control command;

[0090] The flow distribution ratio of the return valve in the left position is calculated based on the lubricating oil flow direction control command, and a lubricating oil flow distribution formula is generated.

[0091] Map the flow allocation ratio to the right position of the featherer valve to trigger the straight-through path activation condition;

[0092] By integrating the flow control commands, flow allocation ratios, and direct path activation conditions, a gate group collaborative verification matrix is ​​constructed.

[0093] The system analyzes the oil circuit on / off rules of the ground beta valve in the left-hand position and outputs lubricating oil flow direction control commands, including target oil chamber identifiers and flow distribution weights. Based on the lubricating oil flow direction control commands, the flow distribution ratio of the heave valve in the left-hand position is calculated, generating a lubricating oil flow distribution formula that reflects the nonlinear relationship between the valve opening and flow rate. The flow distribution ratio is mapped to the feather valve in the right-hand position, and the triggering of the straight-through path activation condition requires meeting a minimum pressure threshold constraint. By integrating the lubricating oil flow direction control commands, flow distribution ratios, and straight-through path activation conditions, a valve group collaborative verification matrix is ​​constructed to verify the multi-valve action conflict rules.

[0094] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 4 includes:

[0095] Activate the high-pressure lubricating oil injection of the feathering pump into the return valve inlet, pushing the lubricating oil into the speed limiter distributor valve;

[0096] In response to the oil pressure increase signal from the oil separator valve, the lubricating oil is driven to flow through the ground beta valve to the servo valve control port;

[0097] Based on the change in the opening of the servo valve control port, lubricating oil is guided into the small-pitch oil chamber of the propeller;

[0098] The pressure difference threshold between the inlet pressure of the small-distance oil chamber and the return pressure of the large-distance oil chamber is detected simultaneously to complete the return oil action of the large-distance oil chamber.

[0099] When the feathering command signal group is loaded:

[0100] Switch the high-pressure lubricating oil from the feather pump to the inlet of the feather valve, directly connecting to the input port of the beta tube bushing;

[0101] Based on the oil load signal of the beta tube bushing, distribute lubricating oil to the large-pitch oil chamber of the propeller;

[0102] The oil inlet rate of the large-distance oil chamber and the oil return rate of the small-distance oil chamber are matched in real time to complete the oil return action of the small-distance oil chamber.

[0103] When the high-pressure lubricating oil from the feathering pump is activated and injected into the return valve inlet, the initial flow velocity of the lubricating oil entering the speed limiter distributor valve is constrained by the pump displacement parameters. Responding to the increased oil pressure signal from the distributor valve, the path of the lubricating oil flowing through the ground beta valve to the servo valve control port is controlled by the valve displacement equation. Based on the opening change of the servo valve control port, the amount of lubricating oil entering the propeller's small-pitch oil chamber is matched to the rate of change of the oil chamber volume. The pressure difference threshold between the small-pitch oil chamber inlet pressure and the large-pitch oil chamber return pressure is simultaneously detected; maintaining the pressure balance equation is necessary to complete the large-pitch oil chamber return action.

[0104] When the feathering command signal group is applied: the high-pressure lubricating oil from the feathering pump is switched to the inlet of the feathering valve, and the path directly to the input port of the beta tube bushing skips the speed limiter oil distribution valve. Based on the oil load signal from the beta tube bushing, the proportion of lubricating oil distributed to the propeller's large-pitch oil chamber is calculated using the flow distribution formula. The oil inlet rate of the large-pitch oil chamber and the oil return rate of the small-pitch oil chamber are matched in real time, and the servo valve opening is dynamically adjusted when the small-pitch oil chamber returns oil.

[0105] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 includes:

[0106] Calculate the real-time area change rate of the flow cross section in the variable pitch oil chamber;

[0107] A lubricating oil flow rate decay curve is generated based on the area change rate.

[0108] Extract the peak and trough characteristic values ​​of the lubricating oil flow rate decay curve;

[0109] Correlate the characteristic values ​​with the hydraulic system pressure fluctuation data, and output a propeller displacement time-domain response report.

[0110] The real-time area change rate of the flow cross-section in the variable-pitch oil chamber is calculated using a geometric topological dynamic analytical algorithm based on the lubricating oil flow path. An oil flow rate decay curve is generated based on the area change rate, reflecting the time-domain correlation between the flow area reduction rate and the flow rate decrease rate. Peak and trough characteristic values ​​of the lubricating oil flow rate decay curve are extracted to identify the maximum decay rate point and the stable inflection point. These characteristic values ​​are correlated with hydraulic system pressure fluctuation data to output a propeller displacement time-domain response report, including a coupled analysis of displacement delay and pressure oscillation.

[0111] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0112] Collect attenuation characteristic data of the propeller blade angular displacement process from 90° to -19°;

[0113] When the flow area shrinks beyond a predetermined threshold, the transient response mode of the attenuation characteristic data is analyzed; the coupling coefficient between lubricating oil viscosity and attenuation rate is calculated based on the transient response mode.

[0114] Establish a mapping relationship between the coupling coefficient and the rate of change of the flow cross section to generate a hydraulic power loss prediction table.

[0115] Data on the attenuation characteristics of the propeller blade angular displacement from 90° to -19° was collected, covering the critical range of small-pitch limited movement in the air. When the flow area reduction exceeds a predetermined threshold, the transient response pattern of the attenuation characteristic data was analyzed to identify the critical point of lubricating oil flow regime transition. Based on the transient response pattern, the coupling coefficient between lubricating oil viscosity and attenuation rate was calculated to establish a physical correlation model of temperature, viscosity, and attenuation. A mapping relationship between the coupling coefficient and the rate of change of the flow cross section was established to generate a hydraulic power loss prediction table to quantify energy loss under different operating conditions.

[0116] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0117] Calculate the deviation between the simulated flow attenuation characteristics and the design specifications;

[0118] The flow bottleneck coordinates of the airborne small-distance limited-movement oil circuit section are located based on the deviation value;

[0119] Generate valve position offset and flow cross-section correction coefficient based on flow bottleneck coordinates;

[0120] The offset and correction coefficient are converted into servo valve control current gradient parameters, and a compensation instruction set is output.

[0121] The deviation between the simulated flow rate attenuation characteristics and the design specifications is calculated using the root mean square error (RMSE) algorithm to locate abnormal fluctuation ranges. Based on the deviation, the flow bottleneck coordinates and associated geometric abrupt changes in the hydraulic circuit section of the small-distance air-operated limit position are located. Based on the flow bottleneck coordinates, valve position offsets are generated to correct the servo valve response delay, and flow cross-section correction coefficients are used to optimize local turbulence effects. The offsets and correction coefficients are converted into servo valve control current gradient parameters, and the output compensation command set includes a current value step change sequence.

[0122] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0123] Import the valve position offset and the flow cross section correction coefficient into the co-simulation model;

[0124] Perform iterative model calculations and collect optimized flow area change rate data;

[0125] Reconstruct the attenuation characteristic curve based on the rate of change data, and calculate the reduction in pitch time.

[0126] When the shortening amount reaches the target range threshold, a hydraulic system characteristic compliance confirmation report is generated.

[0127] The valve position offset and flow cross-section correction coefficient are imported into the co-simulation model to update the boundary constraints. Iterative model calculations are performed, and the optimized flow area change rate data is collected to record the attenuation amplitude improvement rate. The attenuation characteristic curve is reconstructed based on the change rate data, and the reduction in pitch time is calculated and compared to the time consumption under the original operating condition. When the reduction reaches the target interval threshold, a hydraulic system characteristic compliance confirmation report is generated, marking the bottleneck elimination coordinate point.

[0128] Specifically, in the MATLAB simulation method for the feathering and revving function of the propeller system described in this invention, step 5 further includes:

[0129] The servo valve control current gradient parameters are applied to the pitch controller electrical signal input port.

[0130] Call the hydraulic power loss prediction table to calculate the compensated lubricating oil viscosity and attenuation coupling coefficient;

[0131] The data acquisition frequency of the flow area change rate is dynamically adjusted based on the coupling coefficient.

[0132] By correlating the propeller displacement time-domain response report with the pitch reduction, a hydraulic system cooperative gain coefficient is generated.

[0133] When the cooperative gain coefficient exceeds a preset threshold, the ultimate correction strategy for small-distance air-to-ground movement is output.

[0134] The servo valve control current gradient parameters are loaded into the pitch controller's electrical signal input port to activate the compensation command sequence. The hydraulic power loss prediction table is called to calculate the compensated lubricating oil viscosity and attenuation coupling coefficient to correct temperature drift errors. Based on the coupling coefficient, the data acquisition frequency of the flow area change rate is dynamically adjusted, employing a high-frequency sampling mode in the attenuation-sensitive region. The propeller displacement time-domain response report and pitch reduction are correlated to generate a hydraulic system cooperative gain coefficient to evaluate the multi-parameter optimization effect. When the cooperative gain coefficient exceeds a preset threshold, the final correction strategy for small-pitch limiting position in mid-air is output to lock the optimal parameter combination.

[0135] The technical solution of this invention solves the technical problem in optimizing the hydraulic flow attenuation characteristics of a propeller system at small distances in the air by constructing a co-simulation model to replace physical prototype testing. The specific solution path is as follows:

[0136] First, the hydraulic circuit connection paths and structural dimensional parameters of the propeller system are obtained, including the lubricating oil delivery channel from the speed governor's distributor valve to the servo valve, the interface connection path between the beta tube bushing and the propeller pitch chamber, and the pipeline routing from the feathering pump output to the return valve. These parameters are directly derived from actual system design data, avoiding the need for physical prototype machining and lubricating oil resource consumption, and reducing experimental costs.

[0137] Secondly, based on the connection path definition of oil circuit node connection rules, structural dimension parameters are converted into pipe diameter constraints to construct a co-simulation model. The model integrates the oil circuit on / off conditions defined by the ground beta valve displacement equation, the pressure-displacement conversion mechanism of the servo valve current signal and the propeller oil chamber hydraulic feedback node, forming a mathematical framework that can dynamically simulate lubricating oil flow. This step eliminates the need to repeatedly build oil circuit test benches and shortens the iteration cycle.

[0138] When executing the co-simulation model, feathering and revving command signal groups are injected into the electrical signal input port of the pitch controller to drive the simulation calculation of the lubricating oil flow path. The model outputs the hydraulic oil chamber pressure, flow cross-sectional area, and instantaneous flow rate in real time, capturing the dynamic changes in lubricating oil flow rate and the process of flow area reduction. This process achieves dynamic flow transient response monitoring that cannot be achieved by physical testing.

[0139] A mapping table is generated by correlating the time-series changes in the cross-sectional area of ​​the flow passage with the instantaneous flow rate, revealing the quantitative relationship between the area decay and flow rate decrease of the small-distance limiting position oil passage cross-section. Based on the mapping table, the flow bottleneck coordinates are located, and valve position offset and flow passage correction coefficients are generated. The correction parameters are imported into a co-simulation model for iterative verification, and the optimized flow area change rate data is collected to reconstruct the decay characteristic curve. The optimization effect is evaluated by the reduction in pitch time, addressing the difficulty in quantifying transient fluctuations in physical testing.

[0140] Finally, the hydraulic power loss prediction table is used to calculate the coupling coefficient between lubricating oil viscosity and attenuation, and a synergistic gain coefficient is generated by correlating the propeller displacement time-domain response report with the pitch reduction. When the synergistic gain coefficient exceeds a preset threshold, a final correction strategy is output to lock the optimal combination of valve position offset and servo valve control current gradient parameters. The entire process uses data-driven optimization based on simulation models to replace physical experiments, improving the efficiency of analyzing hydraulic attenuation characteristics at small distances in the air.

[0141] This invention addresses the technical pain point of relying on physical prototype testing in the prior art by constructing a hydraulic simulation model of the propeller system. First, the hydraulic oil circuit connections of the propeller system are collected, including the lubricating oil delivery channel from the speed governor's distributor valve to the servo valve, the interface connection path between the beta tube bushing and the propeller pitch chamber, and the pipeline route from the feathering pump output to the return valve. Simultaneously, structural dimensional parameters such as the pitch controller valve displacement stroke, the inner diameter of the oil circuit pipes, and the volume of the pitch chamber are acquired. These data are derived from actual system design drawings, avoiding the need for physical prototype fabrication.

[0142] Based on the connection path definition of oil circuit node connection rules, the pipeline inner diameter is converted into a pipe diameter constraint condition, and a co-simulation model is constructed on the MATLAB simulation platform. The model integrates the oil circuit on / off conditions defined by the ground beta valve displacement equation, configures the rated input range of the feathering pump speed signal port and displacement signal port, and connects the servo valve current signal to the propeller oil chamber hydraulic feedback node to establish a pressure-displacement conversion mechanism. By analyzing the lubricating oil flow direction control command, the flow distribution ratio is calculated, and a valve group collaborative verification matrix is ​​constructed to verify the multi-valve action conflict rules.

[0143] During model execution, a 28VDC feathering command signal group and a 0VDC return-to-pitch command signal group are injected into the pitch controller's electrical signal input port. The simulation calculates the lubricating oil flow path: High-pressure lubricating oil from the activated feathering pump enters the speed governor's distribution valve via the return-to-pitch valve. Responding to the increased oil pressure signal, the lubricating oil flows through the ground beta valve to the servo valve control port. Based on the control port opening change, the lubricating oil is guided into the small-pitch oil chamber, and the differential pressure threshold is simultaneously detected to complete the return-to-pitch oil chamber. The model outputs real-time data on three key elements: hydraulic chamber pressure, flow cross-sectional area, and instantaneous flow rate, capturing transient flow fluctuations when the flow area shrinks at the small-pitch limiting position in the air.

[0144] A mapping table is generated by correlating the temporal variation data of the flow passage cross-sectional area and instantaneous flow rate to identify the flow attenuation characteristics during the blade angle displacement from 90° to -19°. When the flow passage area reduction exceeds a predetermined threshold, the transient response mode is analyzed, and the coupling coefficient between lubricating oil viscosity and attenuation rate is calculated to generate a hydraulic power loss prediction table. Based on the deviation between the simulated flow attenuation characteristics and design specifications, the flow bottleneck coordinates are located, and the valve position offset and flow passage correction coefficient are generated and converted into servo valve control current gradient parameters. The correction parameters are imported into the model for iterative verification, the attenuation characteristic curve is reconstructed, and the pitch reduction time is calculated. When the reduction reaches the target range threshold, a hydraulic system characteristic compliance confirmation report is generated. Finally, the hydraulic power loss prediction table is called to correct the temperature drift error, and a synergistic gain coefficient is generated by correlating the propeller displacement time-domain response report with the pitch reduction time. When the coefficient exceeds a preset threshold, the ultimate correction strategy is output to lock the optimal parameter combination, systematically solving the dynamic optimization problem that cannot be achieved by physical testing.

Claims

1. A MATLAB simulation method for the feathering and swerving functions of a propeller system, characterized in that, include: Step 1: Obtain the hydraulic oil circuit connection path and structural dimension parameters of the propeller system; Step 2: Define the oil circuit node connection rules according to the connection path, convert the structural size parameters into pipe diameter constraints, and construct a joint simulation model based on the connection rules and pipe diameter constraints; Step 3: Locate the electrical signal input port of the pitch controller in the co-simulation model, and inject the feathering command signal group and the revving command signal group into the port; Step 4: Perform a joint simulation model to simulate and calculate the flow path of the lubricating oil, and output the hydraulic oil chamber pressure value, flow cross-sectional area value, and instantaneous flow rate value. Step 5: Generate a mapping table by associating the time-series change data of the flow cross-sectional area value and the instantaneous flow rate value, and formulate an airborne small-distance limiting position correction strategy using the mapping table.

2. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 1, characterized in that, Step 1 includes: The valve displacement switching logic of the pitch controller is read as the reference for hydraulic circuit control; Based on the oil circuit control reference, locate the connection path from the speed limiter oil distributor valve to the servo valve, and measure the oil circuit length of this path; The interface fit dimensions between the beta tube bushing and the propeller pitch chamber are determined based on the oil circuit length. The diameter of the pipe from the output end of the feather pump to the return valve is matched according to the interface adapter size.

3. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 2, characterized in that, Step 2 includes: Construct the displacement equation for the ground beta valve and define the oil circuit on / off conditions for releasing the small-distance movement restriction in the air; Configure the input range of the propeller pump speed signal port and displacement signal port based on the oil circuit on / off conditions; Connect the servo valve current signal to the propeller oil chamber hydraulic feedback node to establish a pressure-displacement conversion mechanism; The path selection function for connecting the left position of the return valve to the speed limiter cavity is generated based on the pressure and displacement conversion mechanism.

4. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 3, characterized in that, Step 2 also includes: Analyze the oil circuit on / off rules of the ground beta valve in the left position and output the lubricating oil flow direction control command; The flow distribution ratio of the return valve in the left position is calculated based on the lubricating oil flow direction control command, and a lubricating oil flow distribution formula is generated. Map the flow allocation ratio to the right position of the featherer valve to trigger the straight-through path activation condition; By integrating the flow control commands, flow allocation ratios, and direct path activation conditions, a gate group collaborative verification matrix is ​​constructed.

5. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 4, characterized in that, Step 4 includes: Activate the high-pressure lubricating oil injection of the feathering pump into the return valve inlet, pushing the lubricating oil into the speed limiter distributor valve; In response to the oil pressure increase signal from the oil separator valve, the lubricating oil is driven to flow through the ground beta valve to the servo valve control port; Based on the change in the opening of the servo valve control port, lubricating oil is guided into the small-pitch oil chamber of the propeller; The pressure difference threshold between the inlet pressure of the small-distance oil chamber and the return pressure of the large-distance oil chamber is detected simultaneously to complete the return oil action of the large-distance oil chamber. When the feathering command signal group is loaded: Switch the high-pressure lubricating oil from the feather pump to the inlet of the feather valve, directly connecting to the input port of the beta tube bushing; Based on the oil load signal of the beta tube bushing, distribute lubricating oil to the large-pitch oil chamber of the propeller; The oil inlet rate of the large-distance oil chamber and the oil return rate of the small-distance oil chamber are matched in real time to complete the oil return action of the small-distance oil chamber.

6. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 5, characterized in that, Step 5 includes: Calculate the real-time area change rate of the flow cross section in the variable pitch oil chamber; A lubricating oil flow rate decay curve is generated based on the area change rate. Extract the peak and trough characteristic values ​​of the lubricating oil flow rate decay curve; Correlate the characteristic values ​​with the hydraulic system pressure fluctuation data, and output a propeller displacement time-domain response report.

7. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 6, characterized in that, Step 5 further includes: Collect attenuation characteristic data of the propeller blade angular displacement process from 90° to -19°; When the flow area shrinks beyond a predetermined threshold, the transient response pattern of the attenuation characteristic data is analyzed. The coupling coefficient between lubricating oil viscosity and decay rate is calculated based on the transient response mode; Establish a mapping relationship between the coupling coefficient and the rate of change of the flow cross section to generate a hydraulic power loss prediction table.

8. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 7, characterized in that, Step 5 further includes: Calculate the deviation between the simulated flow attenuation characteristics and the design specifications; The flow bottleneck coordinates of the airborne small-distance limited-movement oil circuit section are located based on the deviation value; Generate valve position offset and flow cross-section correction coefficient based on flow bottleneck coordinates; The offset and correction coefficient are converted into servo valve control current gradient parameters, and a compensation instruction set is output.

9. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 8, characterized in that, Step 5 further includes: Import the valve position offset and the flow cross section correction coefficient into the co-simulation model; Perform iterative model calculations and collect optimized flow area change rate data; Reconstruct the attenuation characteristic curve based on the rate of change data, and calculate the reduction in pitch time. When the shortening amount reaches the target range threshold, a hydraulic system characteristic compliance confirmation report is generated.

10. The MATLAB simulation method for the feathering and revving function of a propeller system according to claim 9, characterized in that, Step 5 further includes: The servo valve control current gradient parameters are applied to the pitch controller electrical signal input port. Call the hydraulic power loss prediction table to calculate the compensated lubricating oil viscosity and attenuation coupling coefficient; The data acquisition frequency of the flow area change rate is dynamically adjusted based on the coupling coefficient. By correlating the propeller displacement time-domain response report with the pitch reduction, a hydraulic system cooperative gain coefficient is generated. When the cooperative gain coefficient exceeds a preset threshold, the ultimate correction strategy for small-distance air-to-ground movement is output.

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