A control method for suppressing flow pulsation of axial piston pump

Abstract

The present invention discloses a control method for suppressing flow pulsation of an axial piston pump, the method comprising: obtaining an initial rotor phase angle and an initial swash plate inclination angle of the axial piston pump; using the initial rotor phase angle as the current rotor phase angle; using the initial swash plate inclination angle as the current swash plate inclination angle; determining the current flow of the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle; when the absolute value of the difference between the current flow and the flow threshold is greater than the difference threshold, determining the target rotation speed of the swash plate in the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle; the rotation speed of the swash plate is used to control the rate of change of the swash plate inclination angle; the swash plate inclination angle is used to control the flow of the axial piston pump. The present invention reduces the flow pulsation by adjusting the swash plate inclination angle, thereby reducing damage to the axial piston pump.

Description

Technical Field

[0001] The invention relates to the technical field of electro-hydraulic control, and in particular to a control method for suppressing flow pulsation of an axial piston pump. Background Art

[0002] The axial piston pump is an inclined plate type axial piston pump that uses an oil distribution plate to distribute oil, a rotating cylinder, and a variable head to change the volume. The pump has the advantages of simple structure, small size, low noise, high efficiency, long life, and self-priming ability. It is widely used in machine tools, forging, metallurgy, engineering, mining, ships and other machinery and other hydraulic transmission systems. However, the existing axial piston pump has a large flow pulsation when in use. The vibration caused by the flow pulsation will cause system vibration, increase environmental noise, and reduce the system's working reliability. In order to improve the system's working reliability and improve the human-machine friendly environment of the equipment, it is necessary to reduce the flow pulsation of the piston pump from the source. Summary of the invention

[0003] The object of the present invention is to provide a control method for suppressing flow pulsation of an axial piston pump, by adjusting the inclination angle of a swash plate to reduce flow pulsation, thereby reducing damage to the axial piston pump.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] A control method for suppressing flow pulsation of an axial piston pump, comprising:

[0006] Obtaining an initial rotor phase angle and an initial swash plate inclination angle of an axial piston pump;

[0007] Using the initial rotor phase angle as the current rotor phase angle; Using the initial swash plate inclination angle as the current swash plate inclination angle;

[0008] Determining a current flow rate of the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle;

[0009] When the absolute value of the difference between the current flow rate and the flow rate threshold is greater than the difference threshold, the target rotation speed of the swash plate in the axial piston pump is determined according to the current rotor phase angle and the current swash plate inclination angle; the rotation speed of the swash plate is used to control the rate of change of the swash plate inclination angle; and the swash plate inclination angle is used to control the flow rate of the axial piston pump.

[0010] Optionally, after determining the target rotation speed of the swash plate in the axial piston pump, the method further includes:

[0011] The rotation speed of the swash plate in the axial piston pump is adjusted to the target rotation speed; the rotor phase angle of the piston pump at the next moment is used as the current rotor phase angle, the swash plate inclination angle of the piston pump at the next moment is used as the current swash plate inclination angle, and return to the step of "determining the current flow rate of the axial piston pump based on the current rotor phase angle and the current swash plate inclination angle".

[0012] Optionally, the current flow rate of the axial piston pump is determined by:

[0013]

[0014] Among them, Q 总 is the current flow rate of the axial piston pump, A is the piston cavity area, R is the piston rotation radius, is the current rotor phase angle, and its value range is θ is the current swash plate inclination angle, and t is the time.

[0015] Optionally, the formula for determining the rotation speed of the swash plate is:

[0016]

[0017] Wherein, Δv is the target rotation speed of the swash plate, J is the first amplification factor, H is a constant; and G is the second amplification factor.

[0018] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0019] The present invention discloses a control method for suppressing flow pulsation of an axial piston pump, comprising: obtaining an initial rotor phase angle and an initial swash plate inclination angle of the axial piston pump; using the initial rotor phase angle as the current rotor phase angle; using the initial swash plate inclination angle as the current swash plate inclination angle; determining the current flow of the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle; determining the target rotation speed of the swash plate in the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle when the absolute value of the difference between the current flow and the flow threshold is greater than the difference threshold; the rotation speed of the swash plate is used to control the rate of change of the swash plate inclination angle; the swash plate inclination angle is used to control the flow of the axial piston pump. The present invention reduces the flow pulsation by adjusting the swash plate inclination angle, thereby reducing damage to the axial piston pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 This is a flow chart of a control method for suppressing flow pulsation of an axial piston pump in an embodiment of the present invention;

[0022] Figure 2 is a slant plate inclination angle curve diagram in an embodiment of the present invention;

[0023] Figure 3 It is a flow curve diagram in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] The object of the present invention is to provide a control method for suppressing flow pulsation of an axial piston pump, by adjusting the inclination angle of a swash plate to reduce flow pulsation, thereby reducing damage to the axial piston pump.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Figure 1 FIG. 1 is a flow chart of a control method for suppressing flow pulsation of an axial piston pump in an embodiment of the present invention. Figure 1 As shown, the present invention provides a control method for suppressing flow pulsation of an axial piston pump, comprising:

[0028] Step 101: obtaining an initial rotor phase angle and an initial swash plate inclination angle of an axial piston pump;

[0029] Step 102: using the initial rotor phase angle as the current rotor phase angle; using the initial swash plate inclination angle as the current swash plate inclination angle;

[0030] Step 103: determining the current flow rate of the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle;

[0031] Step 104: When the absolute value of the difference between the current flow rate and the flow rate threshold is greater than the difference threshold, the target rotation speed of the swash plate in the axial piston pump is determined according to the current rotor phase angle and the current swash plate inclination angle; the rotation speed of the swash plate is used to control the rate of change of the swash plate inclination angle; the swash plate inclination angle is used to control the flow rate of the axial piston pump.

[0032] After step 104, the method further includes:

[0033] The rotation speed of the swash plate in the axial piston pump is adjusted to the target rotation speed; the rotor phase angle of the piston pump at the next moment is used as the current rotor phase angle, the swash plate inclination angle of the piston pump at the next moment is used as the current swash plate inclination angle, and return to step 103.

[0034] The formula for determining the current flow rate of the axial piston pump is:

[0035]

[0036] Among them, Q 总 is the current flow rate of the axial piston pump, A is the piston cavity area, R is the piston rotation radius, is the current rotor phase angle, and its value range is The flow pulsation period of the six-piston axial piston pump is θ is the current swash plate inclination angle, and t is the time.

[0037] The formula for determining the rotation speed of the swash plate is:

[0038]

[0039] Wherein, Δv is the target rotation speed of the swash plate, J is the first amplification factor, H is a constant; and G is the second amplification factor.

[0040] Specifically, in the present invention, after the structure of the plunger pump is determined, there is a functional relationship between its flow pulsation rate and the inclination angle of the swash plate. During operation, the swash plate angle is dynamically adjusted according to a certain functional relationship, which can achieve the purpose of reducing flow pulsation. Specifically, a phase angle detection device is set on the six-plunger plunger pump, and then the swash plate angle adjustment device is used to change the rotation speed of the swash plate, so that the inclination angle of the swash plate changes, and the flow of the swash plate is further changed, so that the flow of the plunger pump tends to be stable, which greatly improves the performance of the component and the stability of the system. When the plunger pump rotor starts working, the oil enters the plunger cavity. Since the movement of the plunger is a sine curve, the flow stability is adjusted by changing the inclination angle of the swash plate when the speed remains unchanged. The swash plate inclination angle curve before and after the addition of the swash plate angle adjustment device is shown in the figure. Figure 2 As shown; the flow curve before and after adding the swash plate angle adjustment device is as follows Figure 3 As shown; Figure 2 In the figure, the horizontal axis is time, and the vertical axis is the inclination angle of the swash plate; the straight line is the inclination angle of the swash plate before the swash plate angle adjustment device is added, and the curve is the inclination angle of the swash plate after the swash plate angle adjustment device is added. Figure 3 In the figure, the horizontal axis is time and the vertical axis is flow rate; the curve is the inclination angle of the swash plate before the swash plate angle adjustment device is added, and the straight line is the inclination angle of the swash plate after the swash plate angle adjustment device is added. Figure 2-3 It can be seen that before adding the swash plate angle adjustment device, the swash plate angle cannot be adjusted and the flow pulse is large. After adding the controller, the swash plate angle can be adjusted and the flow pulse tends to be stable.

[0041] Plunger displacement curve:

[0042] Plunger speed curve:

[0043] Single plunger flow curve:

[0044] Plunger flow curve:

[0045] Among them, Q 总 is the current flow rate of the axial piston pump, A is the piston cavity area, R is the piston rotation radius, is the current rotor phase angle, θ is the current swash plate inclination angle, and t is time.

[0046] Existing axial piston pumps are often used under high-pressure conditions, and in the case of flow pulsation, they further affect pressure pulsation, which is very likely to cause damage to components and ultimately affect the safety of the system. The present invention uses the change of the inclination angle of the swash plate to reduce flow pulsation. In this design, the flow is idealized, which can not only reduce the pulsation amplitude of the component flow and effectively reduce the vibration of the component, but also reduce energy consumption and increase the service life of the component. It effectively reduces the impact of flow pulsation on components and systems.

[0047] In summary, the present invention has the following advantages:

[0048] 1. When the piston pump starts running, measure the current phase, and then control the swash plate through feedback to achieve flow stability.

[0049] 2. It is more effective to reduce flow pulsation when the controller controls the swash plate speed after amplifying the signal instead of directly controlling the swash plate angle.

[0050] In addition, the present invention adopts closed-loop control to improve the stability of components and systems; integrates the controller and phase sensor to achieve modular design; after reducing the inclination angle of the swash plate, the load on the motor is reduced, and the energy-saving circuit that uses a servo motor and an accumulator for energy recovery recovers the potential energy of self-gravity, thereby saving energy and reducing emissions.

[0051] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0052] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A control method for suppressing flow pulsation of an axial piston pump, characterized in that: The method comprises: Obtaining an initial rotor phase angle and an initial swash plate inclination angle of an axial piston pump; Using the initial rotor phase angle as the current rotor phase angle; Using the initial swash plate inclination angle as the current swash plate inclination angle; Determining a current flow rate of the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle; When the absolute value of the difference between the current flow rate and the flow rate threshold is greater than the difference threshold, a target rotation speed of a swash plate in the axial piston pump is determined according to the current rotor phase angle and the current swash plate inclination angle; the rotation speed of the swash plate is used to control the rate of change of the swash plate inclination angle; the swash plate inclination angle is used to control the flow rate of the axial piston pump; After determining the target rotation speed of the swash plate in the axial piston pump, the method further includes: The rotation speed of the swash plate in the axial piston pump is adjusted to the target rotation speed; the rotor phase angle of the piston pump at the next moment is used as the current rotor phase angle, the swash plate inclination angle of the piston pump at the next moment is used as the current swash plate inclination angle, and the process returns to the step of "determining the current flow rate of the axial piston pump according to the current rotor phase angle and the current swash plate inclination angle"; The formula for determining the current flow rate of the axial piston pump is: Among them, Q 总 is the current flow rate of the axial piston pump, A is the piston cavity area, R is the piston rotation radius, is the current rotor phase angle, and its value range is θ is the current swash plate inclination angle, t is the time; The formula for determining the rotation speed of the swash plate is: Wherein, Δv is the target rotation speed of the swash plate, J is the first amplification factor, H is a constant; and G is the second amplification factor.

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