A method, medium and device for pitch estimation of a controllable pitch propeller

Abstract

The application discloses a pitch estimation method of a controllable pitch propeller, and comprises the following steps: obtaining real-time operation data of the controllable pitch propeller at a given moment to obtain physical parameters of hydraulic oil; solving a gear pump model to obtain volume flow of the hydraulic oil at a gear pump outlet; solving a hydraulic pipeline model and a filter model to obtain pressure and volume flow of the hydraulic oil at a filter outlet; solving a one-way valve model to obtain pressure and volume flow of the hydraulic oil at a one-way valve outlet; solving an overflow valve model to obtain overflow volume flow; solving a control system model and a proportional control valve model to obtain hydraulic oil flow in each flow passage of the proportional control valve; solving an oil distributor model to obtain hydraulic oil flow into a propeller hub cylinder; and solving a propeller hub cylinder model to obtain a piston rod stroke; and solving a rotating blade mechanism model to obtain a real-time estimation value of a pitch angle. The application realizes real-time estimation of the pitch of the controllable pitch propeller and can be used as independent estimation of the pitch of the controllable pitch propeller.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ship power system, and in particular to a method for pitch estimation of a controllable pitch propeller, a medium and an equipment. BACKGROUND

[0002] The controllable pitch propeller is a core component of the ship power system, which can adjust the pitch of the propeller blade to change the thrust size and direction of the propeller under the condition of not changing the shafting steering, convert the power of the main engine into the thrust to the ship, and thus realize the running conditions such as forward navigation, reverse navigation, parking, speed control or maneuvering control, thereby improving the maneuverability and flexibility of the ship.

[0003] The controllable pitch propeller involves multiple key components such as gear pumps, hydraulic pipelines, filters, check valves, overflow valves, control systems, proportional control valves, oil distributors, propeller hub oil cylinders, rotating blade mechanisms, and propeller blades. During operation, the controllable pitch propeller may have faults such as hydraulic oil leakage and valve sticking, which may cause the pitch adjustment speed of the controllable pitch propeller to slow down, the pitch to abnormally fluctuate, or even the pitch to be unable to be adjusted. Once some important components fail, it will seriously affect the maneuverability and safe navigation of the ship. On the other hand, the number of sensors equipped in the controllable pitch propeller is generally small, and the device faults are diversified, hidden, and have complex causal relationships, which brings a series of practical difficulties to fault prediction, diagnosis and repair.

[0004] Therefore, the person skilled in the art is committed to providing a method for pitch estimation of a controllable pitch propeller, a medium and an equipment, which realizes real-time estimation of the pitch of the controllable pitch propeller. SUMMARY

[0005] In view of the defects in the prior art, the technical problem to be solved by the present application is to provide a method, a medium and an equipment capable of real-time estimation of the pitch of a controllable pitch propeller.

[0006] To achieve the above-mentioned purpose, the present application provides a method for pitch estimation of a controllable pitch propeller, comprising the following steps:

[0007] Step 1: obtaining real-time running data of the controllable pitch propeller at a given time to obtain physical property parameters of the hydraulic oil;

[0008] Step 2: solving a gear pump model to obtain the volume flow rate of the hydraulic oil at the outlet of the gear pump;

[0009] Step 3: solving a hydraulic pipeline model and a filter model to obtain the pressure and volume flow rate of the hydraulic oil at the outlet of the filter;

[0010] Step 4: solving a check valve model to obtain the pressure and volume flow rate of the hydraulic oil at the outlet of the check valve;

[0011] Step 5: solving an overflow valve model to obtain the overflow volume flow rate;

[0012] Step 6, solve the control system model and the proportional control valve model to obtain the hydraulic oil flow in each flow passage of the proportional control valve;

[0013] Step 7, solve the oil distributor model to obtain the hydraulic oil flow into the hub cylinder;

[0014] Step 8, solve the hub cylinder model to obtain the piston rod stroke;

[0015] Step 9, solve the vane mechanism model to obtain the real-time estimated value of the pitch angle.

[0016] Preferably, in step 1, the physical property parameters are obtained by querying the hydraulic oil parameter database after obtaining the operation data, the operation data including: the set value signal of the pitch angle θ sp , the pressure p pump of the hydraulic oil at the outlet of the gear pump, the pressure p A of the hydraulic oil at the outlet of the proportional control valve A, the pressure p B of the hydraulic oil at the outlet of the proportional control valve B, the return oil pressure p tank , the hydraulic oil temperature T, and the ship main engine speed n e , and the physical property parameters including: the hydraulic oil density ρ and the hydraulic oil dynamic viscosity μ.

[0017] Further, in step 2, the gear pump model is:

[0018]

[0019] In the formula, Q pump is the volume flow of the hydraulic oil at the outlet of the gear pump, V gth is the pump capacity per revolution, n p is the gear pump speed, and η v is the volumetric efficiency of the gear pump; wherein,

[0020]

[0021] In the formula, p pump,0 is the rated pressure of the hydraulic oil at the outlet of the gear pump, η v,0 is the rated volumetric efficiency corresponding to p pump,0 ;

[0022] n p =k p,e n e

[0023] In the formula, n e is the ship main engine speed, and k p,e is the speed ratio of the gear box between the gear pump and the main engine.

[0024] Further, in step 3, the hydraulic pipeline model is:

[0025] p pump -p pipe = Δp f

[0026]

[0027] where p is the pressure of the hydraulic oil at the outlet of the pipe, Δp is the friction pressure loss of the hydraulic oil in the pipe, Q is the volume flow of the hydraulic oil at the outlet of the pipe; wherein pipe f pipe

[0028]

[0029] where λ is the shape factor, L is the length of the pipe, L is the equivalent length of the pipe due to local resistances, A is the flow area of the pipe, f is the friction factor for turbulent flow, d is the diameter of the pipe, Re is the Reynolds number of the hydraulic oil, Re is the critical Reynolds number; wherein e lam

[0030]

[0031] where ε is the surface roughness; r

[0032] The filter model is:

[0033]

[0034] p pipe -p fliter = k f Q fliter 2

[0035] where Q is the volume flow of the hydraulic oil at the outlet of the filter, p is the pressure of the hydraulic oil at the outlet of the filter, k is the flow resistance coefficient of the hydraulic oil through the filter. filter filter f

[0036] Further, in step 4, the one-way valve model is:

[0037]

[0038] where Q is the volume flow of the hydraulic oil at the outlet of the one-way valve, A is the flow area of the one-way valve, p is the pressure of the hydraulic oil at the outlet of the one-way valve; wherein check check check

[0039] ​​​​​​​​​​​​

[0040] where x check is the spool displacement of the check valve, θ check is the cone angle of the valve seat, d check is the spool diameter of the check valve, A check,leak is the leakage area of the check valve; where,

[0041]

[0042] where p check,min is the pre-valve pressure corresponding to the minimum opening of the check valve, p check,max is the pre-valve pressure corresponding to the maximum opening of the check valve, x check,max is the maximum spool displacement of the check valve.

[0043] Further, in step 5, the relief valve model is:

[0044]

[0045] where Q overflow is the relief volume flow, C overflow is the orifice flow coefficient of the relief valve, A overflow is the flow area of the relief valve; where,

[0046]

[0047] where x overflow is the spool displacement of the relief valve, x overflow,max is the maximum spool displacement of the relief valve, A overflow,max is the maximum flow area of the relief valve corresponding to x overflow,max ; where,

[0048] p in S in +p out S out =p ,pilot S pilot +F ,set +K overlow x overflow

[0049] where S in is the area of the inlet hydraulic oil of the relief valve acting on the spool, S out is the area of the outlet hydraulic oil of the relief valve acting on the spool, S pilot is the area of the pilot port hydraulic oil of the relief valve acting on the spool, p overflow,pilot is the pilot stage pressure of the relief valve, F overflow,set is the set spring pressure of the relief valve, K overflow is the spring constant of the relief valve; where,

[0050]

[0051] where C damp is the orifice flow coefficient of the relief valve orifice, C pilot is the orifice flow coefficient of the relief valve pilot stage, A damp is the flow area of the relief valve orifice, A pilot is the flow area of the relief valve pilot stage.

[0052] Further, in step 6, the control system model is:

[0053]

[0054] where s is the Laplace operator, y cv is the controller output, K P is the gain of the control system, τ I is the integral time constant of the control system, τ D is the derivative time constant of the control system, θ t-1 is the real-time estimate of the pitch angle calculated in the previous beat;

[0055] The proportional control valve spool displacement x cv is:

[0056]

[0057] where τ cv is the time constant of the proportional control valve, x cv,max is the maximum displacement of the proportional control valve spool;

[0058] The proportional control valve model is:

[0059]

[0060] where Q P-A , Q P-B , Q A-T , Q B-T are the hydraulic oil volume flows in the P-A, P-B, A-T, B-T flow passages of the proportional control valve, respectively, A P-A , A P-B , A A-T , A B-T are the flow areas of the P-A, P-B, A-T, B-T flow passages of the proportional control valve, respectively, C cv is the flow coefficient of the proportional control valve; wherein,

[0061]

[0062] A P-A = A B-T

[0063] A P-B = A A-T

[0064] wherein R cv is the equivalent radius of the proportional control valve, x P-A and x P-B are the opening displacements of the flow passages P-A and P-B of the proportional control valve, respectively; wherein,

[0065]

[0066] wherein A cv,max is the maximum flow area of the spool of the proportional control valve.

[0067] Further, in step 7, the oil distributor model is:

[0068]

[0069] wherein Q leak,A and Q leak,B are the leakage amounts of the oil distributor A and B, respectively, m3 / s; h A and h B are the gap lengths of the oil distributor A and B, respectively, m; r A and r B are the gap spacings of the oil distributor A and B, respectively, m; ε e is an eccentricity correction coefficient, dimensionless; p0 is the atmospheric pressure, Pa; and μ is the dynamic viscosity of the hydraulic oil, Pa·s.

[0070] The eccentricity correction coefficient ε e is calculated using the following equation:

[0071] ε e = 1 + 1.5e 2

[0072] wherein e is the eccentricity of the oil distributor, mm.

[0073] The hydraulic oil volume flow Q A into the A cylinder is:

[0074] Q A = Q p-A - Q A-T - Q leak,A

[0075] The hydraulic oil volume flow Q B into the B cylinder is:

[0076] Q B = Q P-B - Q B-T - Q leak,B .

[0077] Further, in step 8, the hub oil cylinder model is:

[0078]

[0079] In the formula, d cylinder is the diameter of the hub oil cylinder, d stem is the diameter of the piston rod, h stem is the stroke of the piston rod, m stem is the mass of the piston rod, F stem is the force of the piston rod; wherein,

[0080] F stem =p B π(d cylinder 2 -d stem 2 )-p A πd cylinder 2 .

[0081] Further, in step 9, the vane mechanism model is:

[0082]

[0083] In the formula, θ is the pitch angle, J is the rotational inertia of the vane, N is the number of vanes, R crank is the radius of the position of the crank disc.

[0084] The application also provides a readable medium, the readable medium storing instructions, the instructions being executed on an electronic device to make the electronic device execute the pitch angle estimation method of the variable-pitch propeller.

[0085] The application also provides an electronic device, comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, the processor being configured to execute the pitch angle estimation method of the variable-pitch propeller when executing the program.

[0086] The application has at least the following beneficial technical effects:

[0087] The pitch estimation method of the variable-pitch propeller provided by the application realizes real-time estimation of the pitch of the variable-pitch propeller, and the real-time estimation value of the pitch angle can be calculated according to the measured data of the measuring point, which can be used as an independent estimation of the pitch of the variable-pitch propeller. The application provides support for performance evaluation and fault warning of the variable-pitch propeller, and helps to improve the operation safety of the variable-pitch propeller. In the operation process of the variable-pitch propeller, when there is a large deviation between the measured value of the pitch angle and the real-time estimation value of the pitch angle, it indicates that the variable-pitch propeller may have a potential fault.

[0088] The propeller pitch estimation method of the application can be used for short-term prediction of the propeller pitch when the set value of the future pitch angle is given, and helps the ship driver to judge the change trend and change range of the pitch angle, and has important application value for the safety of ship driving.

[0089] The concept, specific structure and generated technical effects of the application will be further described below in combination with the drawings, so as to fully understand the purpose, features and effects of the application. BRIEF DESCRIPTION OF DRAWINGS

[0090] Figure 1 is a simplified schematic diagram of the propeller of the embodiment of the application;

[0091] Figure 2 is a flowchart of the propeller pitch estimation method of the embodiment of the application;

[0092] Figure 3 is a running data diagram of the propeller of the embodiment of the application;

[0093] Figure 4 is a comparison diagram of the measured value and the estimated value of the pitch angle of the propeller of the embodiment of the application. DETAILED DESCRIPTION

[0094] The preferred embodiment of the application is described below, so that the technical content is clearer and easier to understand. The application can be embodied in many different forms of embodiments, and the protection scope of the application is not limited to the embodiments mentioned in the text.

[0095] In the drawings, the same components have the same reference numerals, and components with similar structures or functions have similar reference numerals. The size and thickness of each component shown in the drawings are arbitrarily shown, and the size and thickness of each component are not limited in the application. In order to make the drawing clearer, the thickness of some components is appropriately exaggerated in some places in the drawing.

[0096] The application provides a propeller pitch estimation method, establishes a mechanism model of the pitch adjustment process of the propeller, and can calculate the real-time estimated value of the pitch angle according to the measured data to realize real-time estimation of the propeller pitch.

[0097] As shown in Figure 1 is a simplified schematic diagram of the structure of the propeller, which is widely used in the field of ships and is an important equipment of the ship power system. The propeller pitch estimation method of the application is used for real-time estimation of the pitch angle of the rotating blade mechanism.

[0098] As shown in Figure 2 , a specific implementation process of the propeller pitch estimation method of the application is as follows.

[0099] Step 1, obtaining real-time running data of the pitch adjusting propeller at a given time to obtain the physical property parameters of the hydraulic oil.

[0100] In this step, after obtaining the real-time running data of the pitch adjusting propeller at a given time, the physical property parameters of the hydraulic oil are obtained by querying the hydraulic oil physical property parameter database. The running data includes: the set value signal of the pitch angle θ sp , the pressure p pump of the hydraulic oil at the outlet of the gear pump, the pressure p A of the hydraulic oil at the outlet of the proportional control valve A, the pressure p B of the hydraulic oil at the outlet of the proportional control valve B, the return oil pressure p tank , the temperature T of the hydraulic oil, and the speed n e of the main engine of the ship; the physical property parameters include the density ρ of the hydraulic oil and the dynamic viscosity μ of the hydraulic oil.

[0101] Step 2, solving the gear pump model to obtain the volume flow rate of the hydraulic oil at the outlet of the gear pump.

[0102] In this step, the gear pump model is solved according to the pressure p pump of the hydraulic oil at the outlet of the gear pump in the running data to obtain the calculated value of the volume flow rate Q pump of the hydraulic oil at the outlet of the pump.

[0103] Specifically, the gear pump model is:

[0104]

[0105] In the formula, Q pump is the volume flow rate of the hydraulic oil at the outlet of the gear pump, m 3 / s; V gth is the pump capacity per revolution, m 3 ; n p is the gear pump speed, rpm; and η v is the volumetric efficiency of the gear pump, dimensionless.

[0106] The volumetric efficiency η v of the gear pump is calculated as follows:

[0107]

[0108] In the formula, p pump,0 is the rated pressure of the hydraulic oil at the outlet of the gear pump, Pa; and η v,0 is the rated volumetric efficiency corresponding to p pump,0 , dimensionless.

[0109] The gear pump speed n p is calculated as follows:

[0110] n p =k p,en e

[0111] where n e is the rotation speed of the main engine of the ship, rpm; k p,e is the rotation speed ratio of the gear box between the gear pump and the main engine, dimensionless.

[0112] Step 3, solve the hydraulic pipeline model and the filter model to obtain the pressure and volume flow rate of the hydraulic oil at the outlet of the filter.

[0113] In this step, according to the volume flow rate Q pump of the hydraulic oil at the outlet of the gear pump obtained in Step 2, the pressure p filter and the volume flow rate Q filter of the hydraulic oil at the outlet of the filter are calculated by solving the hydraulic pipeline model and the filter model.

[0114] The hydraulic pipeline model is:

[0115] p pump -p pipe = Δp f

[0116]

[0117] where p pipe is the pressure of the hydraulic oil at the outlet of the pipeline, Pa; Δp f is the friction pressure loss of the hydraulic oil in the pipeline, Pa; Q pipe is the volume flow rate of the hydraulic oil at the outlet of the pipeline, m 3 / s.

[0118] The friction pressure loss Δp f of the hydraulic oil in the pipeline is calculated as follows:

[0119]

[0120] where λ is the shape coefficient, dimensionless; L is the length of the pipeline, m; L e is the equivalent length of the pipeline caused by local resistance, m; A is the flow area of the pipeline, m 2 ; f is the turbulent friction coefficient, dimensionless; d is the diameter of the pipeline, m; Re is the Reynolds number of the hydraulic oil, dimensionless; Re lam is the critical Reynolds number, dimensionless.

[0121] The turbulent friction coefficient f is calculated as follows:

[0122]

[0123] where ε r is the surface roughness, m.

[0124] The filter model is:

[0125]

[0126] p pipe -p fliter =k f Q fliter 2

[0127] wherein k f is the flow resistance coefficient of the hydraulic oil through the filter, kg / m 7 .

[0128] Step 4, solve the one-way valve model to obtain the pressure and volumetric flow rate of the hydraulic oil at the outlet of the one-way valve.

[0129] In this step, according to the calculated values of the pressure p filter and volumetric flow rate Q filter of the hydraulic oil at the outlet of the filter obtained in Step 3, the one-way valve model is solved to obtain the calculated values of the pressure p check and volumetric flow rate Q check of the hydraulic oil at the outlet of the one-way valve.

[0130] The one-way valve model is:

[0131]

[0132] wherein Q check is the volumetric flow rate of the hydraulic oil at the outlet of the one-way valve, m 3 / s; A check is the flow area of the one-way valve, m 2 ; and p check is the pressure of the hydraulic oil at the outlet of the one-way valve, Pa.

[0133] The flow area A check of the one-way valve is calculated as follows:

[0134]

[0135] wherein x check is the displacement of the spool of the one-way valve, m; θ check is the taper angle of the valve seat, deg; d check is the diameter of the spool of the one-way valve, m; and A check,leak is the leakage area of the one-way valve, m 2 .

[0136] The displacement x check of the spool of the one-way valve is calculated as follows:

[0137]

[0138] wherein p check,min is the pre-valve pressure corresponding to the minimum opening of the check valve, Pa; p check,max is the pre-valve pressure corresponding to the maximum opening of the check valve, Pa; x check,max is the maximum displacement of the check valve spool, m.

[0139] Step 5, solve the relief valve model to obtain the relief volume flow.

[0140] In this step, according to the measured values of the hydraulic oil pressure p A at the A port of the proportional control valve and the hydraulic oil pressure p B at the B port of the proportional control valve in the operation data, the relief valve model is solved to obtain the relief volume flow Q overflow .

[0141] The relief valve model is:

[0142]

[0143] wherein C overflow is the orifice flow coefficient of the relief valve, dimensionless; A overflow is the flow area of the relief valve, m 2 .

[0144] The flow area A overflow of the relief valve is calculated as follows:

[0145]

[0146] wherein x overflow is the displacement of the relief valve spool, m; x overflow,max is the maximum displacement of the relief valve spool, m; A overflow,max is the maximum flow area of the relief valve corresponding to x overflow,max , m 2 .

[0147] The displacement x overflow of the relief valve spool is calculated as follows:

[0148] p in S in +p out S out =p ,pilot S pilot +F ,set +K overlow x overflow

[0149] wherein S in is the area of the inlet hydraulic oil of the relief valve acting on the spool, m 2 ; S outA is the area of the spool acted on by the outlet hydraulic oil of the relief valve, m 2 ; S pilot A is the area of the spool acted on by the pilot hydraulic oil of the relief valve, m 2 ; p overflow,pilot P is the pilot stage pressure of the relief valve, Pa; F overflow,set K is the spring pressure set for the relief valve, N; K overflow K is the spring constant of the relief valve, N / m.

[0150] Pilot stage pressure p of the relief valve overflow,pilot is calculated by the following way:

[0151]

[0152] In the formula, C damp is the orifice flow coefficient of the relief valve, dimensionless; C pilot is the orifice flow coefficient of the pilot stage of the relief valve, dimensionless; A damp A is the flow area of the orifice of the relief valve, m 2 ; A pilot A is the flow area of the pilot stage of the relief valve, m 2 .

[0153] Step 6, solve the control system model and the proportional control valve model to obtain the hydraulic oil flow in each flow passage of the proportional control valve.

[0154] In this step, according to the set value signal θ sp of the pitch angle in the running data, the control system model is solved to obtain the spool displacement x cv of the proportional control valve; according to the return oil pressure p tank measurement value in the running data and the relief volume flow Q overflow calculated value obtained in step 5, the proportional control valve model is solved to obtain the hydraulic oil volume flow Q P-A , Q P-B , Q A-T , Q B-T calculated values in the P-A, P-B, A-T, B-T flow passages of the proportional control valve.

[0155] The control system model is:

[0156]

[0157] In the formula, s is the Laplace operator, y cv is the output result of the controller, dimensionless; K P is the gain of the control system, dimensionless; τ I is the integral time constant of the control system, s; τ D is the differential time constant of the control system, s; θt-1 is the real-time estimation value of the pitch angle calculated in the last frame, deg.

[0158] Proportional control valve spool displacement x cv is calculated by the following way:

[0159]

[0160] In the formula, τ cv is the time constant of the proportional control valve, s; x cv,max is the maximum displacement of the proportional control valve spool, m.

[0161] The proportional control valve model is:

[0162]

[0163] In the formula, Q P-A , Q P-B , Q A-T , Q B-T are the hydraulic oil volume flow rates in the P-A, P-B, A-T, B-T flow passages of the proportional control valve, m 3 / s; A P-A , A P-B , A A-T , A B-T are the flow areas of the P-A, P-B, A-T, B-T flow passages of the proportional control valve, m 2 ; C cv is the flow coefficient of the proportional control valve, dimensionless.

[0164] The flow areas A P-A , A P-B , A A-T , A B-T of the P-A, P-B, A-T, B-T flow passages of the proportional control valve are calculated by the following way:

[0165]

[0166] A P-A = A B-T

[0167] A P-B = A A-T

[0168] In the formula, R cv is the equivalent radius of the proportional control valve, m; x P-A , x P-B are the opening displacements of the P-A, P-B flow passages of the proportional control valve.

[0169] The equivalent radius R cv of the proportional control valve is calculated by the following way:The calculation is as follows:

[0170]

[0171] wherein A cv,max is the maximum flow area of the proportional control valve spool, m 2 .

[0172] Step 7, solve the oil distributor model to obtain the hydraulic oil flow rate into the hub oil cylinder.

[0173] In this step, the hydraulic oil volume flow rates Q P-A , Q P-B , Q A-T , and Q B-T in the P-A, P-B, A-T, and B-T flow passages of the proportional control valve obtained in Step 6 are calculated, and the oil distributor model is solved to obtain the hydraulic oil volume flow rate calculation value into the hub oil cylinder.

[0174] The oil distributor model is as follows:

[0175]

[0176] wherein Q leak,A and Q leak,B are the leakage rates at the A and B ports of the oil distributor, m3 / s; h A and h B are the gap lengths at the A and B ports of the oil distributor, m; r A and r B are the gap spacings at the A and B ports of the oil distributor, m; ε e is the eccentricity correction coefficient, dimensionless; p0 is the atmospheric pressure, Pa; and μ is the dynamic viscosity of the hydraulic oil, Pa·s.

[0177] The eccentricity correction coefficient ε e is calculated using the following formula:

[0178] ε e = 1 + 1.5e 2

[0179] wherein e is the eccentricity of the oil distributor, mm.

[0180] The hydraulic oil volume flow rate of the hub oil cylinder includes the hydraulic oil volume flow rates Q A and Q B into the A and B oil cylinders, respectively, which are calculated as follows:

[0181] Q A = Q p-A -Q A-T -Q leak,A

[0182] QB = Q P-B - Q B-T - Q leak,B

[0183] Step 8, solve the hub cylinder model to obtain the piston rod stroke.

[0184] In this step, the hub cylinder model is solved according to the calculated value of the hydraulic oil volume flow entering the hub cylinder obtained in step 7 to obtain the piston rod stroke h stem .

[0185] The hub cylinder model is:

[0186]

[0187] In the formula, d cylinder is the diameter of the hub cylinder, m; d stem is the diameter of the piston rod, m; h stem is the stroke of the piston rod, m; m stem is the mass of the piston rod, kg; F stem is the force on the piston rod, N.

[0188] The force F stem on the piston rod is calculated as follows:

[0189] F stem = p B π(d cylinder 2 -d stem 2 )-p A πd cylinder 2 .

[0190] Step 9, solve the vane mechanism model to obtain the real-time estimated value of the pitch angle.

[0191] In this step, the vane mechanism model is solved according to the calculated value of the piston rod stroke h stem obtained in step 8 to obtain the real-time estimated value of the pitch angle θ.

[0192] The vane mechanism model is:

[0193]

[0194] In the formula, θ is the pitch angle, deg; J is the rotational inertia of the blade, kg·m 2 ; N is the number of blades, dimensionless; R crank is the radius at the position of the crank disc, m.

[0195] Using the propeller pitch estimation method of the application, first, real-time running data of the controllable pitch propeller is acquired, a set of specific running data is shown in Figure 3 After the pitch estimation method of the embodiment is calculated, the real-time estimated value of the pitch angle is obtained, which is compared with the measured value as shown in Figure 4 Figure 4 It can be seen that the maximum error between the measured value and the estimated value is 0.3 deg, which meets the requirement.

[0196] Another embodiment of the application also provides a readable medium, the readable medium has instructions stored thereon, the instructions, when executed on an electronic device, cause the electronic device to execute the controllable pitch propeller pitch angle estimation method described above.

[0197] Another embodiment of the application also provides an electronic device, which comprises a memory, a processor and a computer program stored on the memory and capable of running on the processor, and the processor is configured to execute the controllable pitch propeller pitch angle estimation method of the above embodiment when executing the program.

[0198] The preferred embodiments of the application are described in detail above. It should be understood that those skilled in the art can make many modifications and variations without creative labor based on the concept of the application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment based on the prior art according to the concept of the application shall be within the protection scope defined by the claims.​

Claims

1. A method for estimating the pitch of a controllable propeller, characterized in that, Includes the following steps: Step 1: Obtain the real-time operating data of the pitch control propeller at a given time to obtain the physical property parameters of the hydraulic oil; In step 1, after acquiring the operating data, the physical property parameters are obtained by querying the hydraulic oil parameter database. The operating data includes: the set value signal of the pitch angle. θ sp Pressure of hydraulic oil at gear pump outlet p pump The pressure of hydraulic oil at port A of the proportional control valve p A The pressure of hydraulic oil at port B of the proportional control valve p B Return oil pressure p tank Hydraulic oil temperature T Ship's main engine speed n e The physical properties include: hydraulic oil density. ρ Hydraulic oil dynamic viscosity μ ; Step 2: Solve the gear pump model to obtain the volumetric flow rate of the hydraulic oil at the gear pump outlet; In step 2, based on the pressure of the hydraulic oil at the gear pump outlet from the operating data... p pump Solve the gear pump model to obtain the volumetric flow rate of the hydraulic oil at the pump outlet. Q pump The calculated value; Step 3: Solve the hydraulic pipeline model and filter model to obtain the pressure and volumetric flow rate of the hydraulic oil at the filter outlet; In step 3, the volumetric flow rate of the hydraulic oil at the gear pump outlet obtained in step 2 is used as a basis. Q pump The calculated values ​​are obtained by solving the hydraulic pipeline model and filter model to obtain the pressure of the hydraulic oil at the filter outlet. p filter and volumetric flow rate Q filter Calculated value; Step 4: Solve the check valve model to obtain the pressure and volumetric flow rate of the hydraulic oil at the check valve outlet; In step 4, the filter outlet hydraulic oil pressure obtained in step 3 is used as a basis. p filter and volumetric flow rate Q filter Calculate the value, solve the one-way valve model, and obtain the pressure of the hydraulic oil at the outlet of the one-way valve. p check and volumetric flow rate Q check Calculated value; Step 5: Solve the overflow valve model to obtain the overflow volumetric flow rate; In step 5, the hydraulic oil pressure at port A of the proportional control valve is used as a reference in the operating data. p A Hydraulic oil pressure at port B of proportional control valve p B The measured values ​​were used to solve the overflow valve model and obtain the overflow volumetric flow rate. Q overflow Calculated value; Step 6: Solve the control system model and the proportional control valve model to obtain the hydraulic oil flow rate in each flow channel of the proportional control valve; In step 6, the pitch angle setting signal in the operating data is used. θ sp Solve the control system model to obtain the valve core displacement of the proportional control valve. x cv Based on the return oil pressure in the operating data p tank The measured values ​​and the overflow volumetric flow rate obtained in step 5 Q overflow Calculate the values, solve the proportional control valve model, and obtain the hydraulic oil volumetric flow rate in the PA, PB, AT, and BT channels of the proportional control valve. Q P-A , Q P-B , Q A-T , Q B-T Calculated value; Step 7: Solve the distributor model to obtain the hydraulic oil flow rate entering the propeller hub cylinder; In step 7, the hydraulic oil volumetric flow rate in the PA, PB, AT, and BT channels of the proportional control valve obtained in step 6 is used as a basis. Q P-A , Q P-B , Q A-T , Q B-T The calculated value is obtained by solving the distributor model and obtaining the calculated value of the hydraulic oil volume flow rate entering the propeller cylinder. Step 8: Solve the impeller hub cylinder model to obtain the piston rod stroke; In step 8, based on the calculated volumetric flow rate of the hydraulic oil entering the hub cylinder obtained in step 7, the hub cylinder model is solved to obtain the piston rod stroke. h stem Calculated value; Step 9: Solve the impeller mechanism model to obtain the real-time estimated value of the pitch angle; In step 9, the piston rod stroke obtained in step 8 is used as a basis. h stem Calculate the value, solve the impeller mechanism model, and obtain the pitch angle. θ The real-time estimated value.

2. The pitch estimation method for controllable propellers as described in claim 1, characterized in that, In step 2, the gear pump model is as follows: In the formula, Q pump It is the volumetric flow rate of the hydraulic oil at the gear pump outlet. V gth It is the pump capacity per revolution. n p It is the gear pump speed. η v This refers to the volumetric efficiency of the gear pump; among which, In the formula, p pump,0 This is the rated pressure of the hydraulic oil at the gear pump outlet. η v,0 yes p pump,0 The corresponding rated volumetric efficiency; In the formula, n e It is the speed of the ship's main engine. k p,e It is the speed ratio of the gearbox between the gear pump and the main unit.

3. The pitch estimation method for controllable propellers as described in claim 2, characterized in that, In step 3, the hydraulic pipeline model is as follows: In the formula, p pipe It is the pressure of the hydraulic oil at the pipeline outlet, Δ p f It is the frictional pressure loss of hydraulic oil within the pipeline. Q pipe It is the volumetric flow rate of the hydraulic oil at the pipeline outlet; in, In the formula, λ It is the shape factor. L It is the pipeline length. L e It is the equivalent pipeline length caused by local resistance. A It refers to the flow area of ​​the pipeline. f It is the coefficient of turbulent friction. d It is the diameter of the pipe. Re It is the Reynolds number of the hydraulic oil. Re lam It is the critical Reynolds number; where, In the formula, ε r It refers to surface roughness; The filter model is: In the formula, Q filter It is the volumetric flow rate of the hydraulic oil at the filter outlet. p filter It is the pressure of the hydraulic oil at the filter outlet. k f It is the flow resistance coefficient of hydraulic oil after passing through the filter.

4. The pitch estimation method for controllable propellers as described in claim 3, characterized in that, In step 4, the one-way valve model is as follows: In the formula, Q check It is the hydraulic oil volume flow rate at the outlet of the check valve. A check It is the flow area of ​​the check valve. p check It is the pressure of the hydraulic oil at the outlet of the check valve; among which, In the formula, x check It refers to the displacement of the check valve spool. θ check It is the cone angle of the valve seat. d check It is the valve core diameter of the check valve. A check,leak It is the leakage area of ​​the check valve; among which, In the formula, p check,min This is the inlet pressure corresponding to the minimum opening degree of the check valve. p check,max This is the inlet pressure corresponding to the maximum opening degree of the check valve. x check,max It is the maximum displacement of the check valve spool.

5. The pitch estimation method for a controllable propeller as described in claim 4, characterized in that, In step 5, the overflow valve model is as follows: In the formula, Q overflow It is the overflow volumetric flow rate. C overflow It is the orifice flow coefficient of the relief valve. A overflow It is the flow area of ​​the overflow valve; in, In the formula, x overflow It is the displacement of the relief valve spool. x overflow,max This is the maximum displacement of the relief valve spool. A overflow,max yes x overflow,max The corresponding maximum flow area of ​​the relief valve; among which, In the formula, S in It refers to the area of ​​the valve core where the inlet hydraulic oil of the relief valve acts. S out It refers to the area of ​​the outlet hydraulic oil acting on the valve core of the relief valve. S pilot It refers to the area of ​​the hydraulic oil acting on the valve core in the pilot port of the relief valve. p overflow,pilot It is the pilot stage pressure of the relief valve. F overflow,set It is the spring pressure set by the relief valve. K overflow It is the spring constant of the relief valve; where, In the formula, C damp It is the orifice flow coefficient of the damping orifice of the overflow valve. C pilot It is the orifice flow coefficient of the relief valve pilot stage. A damp It is the flow area of ​​the damping orifice of the overflow valve. A pilot It is the flow area of ​​the pilot stage of the relief valve.

6. The pitch estimation method for a controllable propeller as described in claim 5, characterized in that, In step 6, the control system model is as follows: In the formula, s It is the Laplace operator. y cv It is the controller output. K P It is the gain of the control system. τ I It is the integral time constant of the control system. τ D It is the differential time constant of the control system. θ t-1 It is a real-time estimate of the pitch angle calculated in the previous step; proportional control valve spool displacement x cv for: In the formula, τ cv It is the time constant of the proportional control valve. x cv,max This is the maximum displacement of the valve core in a proportional control valve. The proportional control valve model is as follows: In the formula, Q P-A , Q P-B , Q A-T , Q B-T These refer to the hydraulic oil volumetric flow rates in the PA, PB, AT, and BT channels of the proportional control valve. A P-A , A P-B , A A-T , A B-T These refer to the flow areas of the proportional control valves PA, PB, AT, and BT channels. C cv It is the flow coefficient of the proportional control valve; where, In the formula, R cv It is the equivalent radius of the proportional control valve. x P-A , x P-B These are the opening displacements of the flow channels PA and PB of the proportional control valve, respectively; where, In the formula, A cv,max It is the maximum flow area of ​​the proportional control valve core.

7. The pitch estimation method for controllable propellers as described in claim 6, characterized in that, In step 7, the distributor model is as follows: In the formula, Q leak,A and Q leak,B These are the leakage rates at ports A and B of the oil distributor, respectively, in m³ / s. h A and h B These are the gap lengths between ports A and B of the oil distributor, in meters; r A and r B These are the gaps between ports A and B of the oil distributor, in meters; ε e It is the eccentricity correction coefficient, which is dimensionless; p 0 is atmospheric pressure, Pa; μ It is the dynamic viscosity of hydraulic oil, Pa·s. The eccentricity correction coefficient ε e Calculate using the following formula: In the formula, e It is the eccentricity of the oil distributor, in mm. Hydraulic oil volume flow rate entering cylinder A Q A for: Hydraulic oil volume flow rate entering cylinder B Q B for: 。 8. The pitch estimation method for a controllable propeller as described in claim 7, characterized in that, In step 8, the impeller hub cylinder model is as follows: In the formula, d cylinder It is the diameter of the propeller hub cylinder. d stem It is the diameter of the piston rod. h stem It refers to the piston rod's stroke. m stem It is the mass of the piston rod. F stem It is the force on the piston rod; among which, 。 9. The pitch estimation method for a controllable propeller as described in claim 8, characterized in that, In step 9, the model of the vane mechanism is as follows: In the formula, θ It is the pitch angle. J N is the moment of inertia of the propeller blades, and N is the number of blades. R crank It is the radius of the location of the crank and crank plate.

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