Burst-coupling adaptive control method and system for array-type independently controllable nozzles

Abstract

The present invention provides a burst-coupled adaptive control method for an array of independently controllable nozzles, which uses a preset valve opening and a single neuron PID adaptive control method to achieve precise pressure control. The inlet regulating valve is preset with a fixed opening, which plays a role in throttling, reducing pressure, and isolating mutual influence on each branch; the outlet regulating valve is first preset with an opening, and quickly responds to the preliminary control of the branch pressure, and then a single neuron PID adaptive control method is used to achieve precise control of the pressure of each branch. This method can be used to achieve wide-range, high-precision water supply pressure control. This method has strong anti-interference and robustness, has better adaptability to the control of the water supply pressure of multiple spray rakes, and achieves precise control of the pressure of each branch.

Description

Technical Field

[0001] The invention belongs to the technical field of near-air icing simulation test for an aero-engine environment, and in particular relates to a burst-type coupling adaptive control method and system for an array of independently controllable nozzles. Background Art

[0002] The engine intake icing test uses a spray system to simulate a foggy environment. Important parameters of a foggy environment include liquid water content, average droplet diameter, etc. These parameters are achieved by the spray system by controlling a certain water supply pressure. Therefore, the control of the spray rake water supply pressure is crucial.

[0003] The existing spray system water supply pressure control circuit includes a main circuit and multiple parallel branch circuits. The main circuit is controlled by a main regulating valve. The parallel branch circuits are equipped with spray rakes, and multiple nozzles are installed on the spray rakes. The nozzle inlet pressure of each branch is controlled separately by the inlet regulating valve at the front end of the branch and the outlet regulating valve at the rear end. At this time, for a certain working pressure, it can be obtained by different combinations of the main regulating valve opening, the inlet regulating valve opening and the outlet regulating valve opening, but there will be serious mutual interference problems when the three are adjusted at the same time. In addition, adjusting the inlet regulating valve opening of any branch will affect the main pressure, and then affect the pressure of other branches, and also cause the passive adjustment of the inlet regulating valves of other branches. Due to the large number of parallel branches and a certain height difference, there is a very serious coupling problem, which will make it difficult to achieve accurate control of the pressure of each branch. And it is difficult to accurately model valves and nozzles. There is little relevant information on the water supply pressure control method of multi-channel spray rakes, and most of them still use traditional PID control, which has poor control accuracy and long adjustment time.

[0004] Therefore, the prior art requires a method that can improve the control accuracy and response speed of the water supply pressure of multiple spray rakes to solve the problems of slow response and low control accuracy of traditional PID. Summary of the invention

[0005] In order to solve the above problems, the purpose of the present invention is to provide a burst-coupled adaptive control method for array-type independently controllable nozzles to solve the characteristics of strong coupling, difficult modeling and slow response between water supply pressures of multiple spray rakes in the prior art.

[0006] In order to achieve the above object, the present invention provides the following technical solution, providing a burst-type coupled adaptive control method of an array of independently controllable nozzles, the method comprising the following steps:

[0007] S1: Collect the water supply pressure at the main pipe inlet, the water supply pressure at the main pipe outlet, the water supply pressure at the inlet of each branch, the water supply pressure at the outlet of each branch, the opening of the main pipe inlet regulating valve, the opening of the main pipe outlet regulating valve, the opening of the inlet regulating valve of each branch and the opening of the outlet regulating valve of each branch;

[0008] S2: Let the water pump run at a constant speed, and the main water return regulating valve is closed-loop controlled to keep the spray rack inlet pressure constant;

[0009] S3: When the inlet pressure of the s2 spray rack is kept constant, adjust the inlet regulating valve and outlet regulating valve of each branch so that the opening of the inlet regulating valve and the outlet regulating valve is at the initial opening, fix the opening of each branch outlet regulating valve, close the loop to adjust the opening of each branch inlet regulating valve, and fix the opening of each branch inlet regulating valve after the pressure in each branch is stable;

[0010] S4: Based on the pressure inside the rake of each branch obtained in S3 and the nozzle characteristics under the current working conditions, the flow loss on the branch is calculated;

[0011] S5: According to the flow loss calculated in S4, the opening of each branch outlet regulating valve is preset for rough adjustment;

[0012] S6: Based on the coarse adjustment of S5, enter the closed-loop control for fine adjustment to achieve rapid stabilization of the pressure of each branch within 10 seconds.

[0013] The burst-type coupled adaptive control method of the array-type independently controllable nozzles provided by the present invention also has the following characteristics: the water supply pressure at the main pipe inlet, the water supply pressure at the main pipe outlet, the water supply pressure at the inlet of each branch and the water supply pressure at the outlet of each branch in S1 are obtained by pressure sensors arranged at corresponding positions; the opening of the main pipe inlet regulating valve, the opening of the main pipe outlet regulating valve, the opening of the inlet regulating valve of each branch and the opening of the outlet regulating valve of each branch are obtained by displacement sensors arranged at corresponding positions.

[0014] The burst-type coupling adaptive control method of the array-type independently controllable nozzles provided by the present invention also has the following characteristics: the spray rack inlet pressure P in S2 is r for:

[0015] P r =P b -ΔP m

[0016] Among them, P b is the pump outlet pressure; ΔP m Local and along-the-way pressure loss of the main road.

[0017] The burst-type coupling adaptive control method of the array-type independently controllable nozzle provided by the present invention also has the following characteristics: in S3, the pressure P at the front end of the i-th spray rake inlet regulating valve is ri for:

[0018] P ri =P r -ΔP mri -P hri

[0019] Among them, ΔP mri is the pressure loss from the spray rack inlet to the front end of the regulating valve at the i-th rake inlet; P hri is the pressure drop due to the height difference of the regulating valve from the spray rack inlet to the i-th rake inlet.

[0020] The burst-type coupling adaptive control method of the array-type independently controllable nozzles provided by the present invention also has the following feature: the initial opening in S3 is not less than 15%.

[0021] The burst-type coupling adaptive control method of the array-type independently controllable nozzle provided by the present invention also has the following characteristics: in S3, the flow loss on the branch is the flow loss on the spray rake arranged on the branch, and the total flow loss Q on the spray rake is t for:

[0022] Q t =Q w *n

[0023] Among them, Q w is the water flow rate of a single nozzle, and n is the number of nozzles on the spray rake.

[0024] The burst coupling adaptive control method of the array type independently controllable nozzle provided by the present invention also has the following characteristics: in said S5, the opening V of each branch outlet regulating valve is preset o for:

[0025]

[0026] Among them, R is the maximum flow rate of the valve Q max With minimum flow Q min The ratio, Q f is the valve flow after compensation, Q is the current valve flow, L / L max is the relative opening of the valve,

[0027] Among them, the compensated valve flow Q f for:

[0028] Q f =QQ t ,

[0029] Q t It is the flow rate lost by the nozzle due to the opening of the spray rake outlet regulating valve.

[0030] The burst-coupling adaptive control method for array-type independently controllable nozzles provided by the present invention also has the following feature: in S6, the opening of each branch spray rake outlet regulating valve is fine-tuned by a single neuron adaptive controller.

[0031] The burst-type coupled adaptive control method of the array-type independently controllable nozzles provided by the present invention also has the following characteristics: the adjustment of the weight coefficient is implemented according to the supervised Hebb learning rule, and the control algorithm and the learning algorithm are as follows:

[0032]

[0033]

[0034] w 1 (k) = w 1 (k-1)+η I z(k)u(k)(e(k)+Δe(k))

[0035] w 2 (k) = w 2 (k-1)+η P z(k)u(k)(e(k)+Δe(k))

[0036] w 3 (k) = w 3 (k-1)+η D z(k)u(k)(e(k)+Δe(k))

[0037] In the formula, x 1 (k) = e(k); x 2 (k) = e(k) - e(k-1); x 3 (k) = e(k) - 2e(k - 1) + e(k - 2);

[0038] z(k)=e(k);η I , η P , η D are the learning rates of integration, proportion, and differentiation respectively; K is the proportional coefficient of the neuron, K>0,

[0039] Among them, e(k) is the difference between the pressure setting value and the sampling value at the current moment, e(k-1) is the difference between the pressure setting value and the sampling value at the previous moment, and e(k-2) is the difference between the pressure setting value and the sampling value at the moment before that.

[0040] Beneficial Effects

[0041] The burst-coupled adaptive control method for array-type independently controllable nozzles provided by the present invention realizes precise control of pressure by presetting valve opening and single neuron PID adaptive control method. The inlet regulating valve is preset with a fixed opening, which plays a role of throttling, reducing pressure, and isolating mutual influence on each branch; the outlet regulating valve is first preset with an opening, and quickly responds for preliminary control of branch pressure, and then a single neuron PID adaptive control method is adopted to realize precise control of each branch pressure. This method can realize wide range and high-precision water supply pressure control. This method has strong anti-interference and robustness, has better adaptability to the control of water supply pressure of multiple spray rakes, and realizes precise control of pressure in each branch. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, 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 disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0043] Figure 1 A schematic diagram of the layout of an array of independently controllable nozzles provided in an embodiment of the present invention;

[0044] Figure 2 A schematic diagram of a pressure control system for an array of independently controllable nozzles provided in an embodiment of the present invention;

[0045] Figure 3 A structural block diagram of a burst-type coupled adaptive control system for an array of independently controllable nozzles provided in an embodiment of the present invention;

[0046] Figure 4 This is a SPIDNN control block diagram for the burst-coupled adaptive control method for array-type independently controllable nozzles provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0047] The present invention is further described in detail below in conjunction with the accompanying drawings and examples, but it should be noted that these implementation modes are not limitations of the present invention, and equivalent changes or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these implementation modes are all within the scope of protection of the present invention.

[0048] In the description of the embodiments of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the invention.

[0049] In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more.

[0050] The terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0051] like Figure 1-Figure 4 As shown, an embodiment of the present invention provides a burst-type coupling adaptive control method for an array of independently controllable nozzles, the method comprising the following steps:

[0052] S1: Collect the water supply pressure at the main pipe inlet, the water supply pressure at the main pipe outlet, the water supply pressure at the inlet of each branch, the water supply pressure at the outlet of each branch, the opening of the main pipe inlet regulating valve, the opening of the main pipe outlet regulating valve, the opening of the inlet regulating valve of each branch and the opening of the outlet regulating valve of each branch;

[0053] S2: Let the water pump run at a constant speed, and the main water return regulating valve is closed-loop controlled to keep the spray rack inlet pressure constant;

[0054] S3: When the inlet pressure of the s2 spray rack is kept constant, adjust the inlet regulating valve and outlet regulating valve of each branch so that the opening of the inlet regulating valve and the outlet regulating valve is at the initial opening, fix the opening of each branch outlet regulating valve, close the loop to adjust the opening of each branch inlet regulating valve, and fix the opening of each branch inlet regulating valve after the pressure in each branch is stable;

[0055] S4: Based on the pressure inside the rake of each branch obtained in S3 and the nozzle characteristics under the current working conditions, the flow loss on the branch is calculated;

[0056] S5: According to the flow loss calculated in S4, the opening of each branch outlet regulating valve is preset for rough adjustment;

[0057] S6: Based on the coarse adjustment of S5, enter the closed-loop control for fine adjustment to achieve rapid stabilization of the pressure of each branch within 10 seconds.

[0058] In some embodiments, the water supply pressure at the main pipe inlet, the water supply pressure at the main pipe outlet, the water supply pressure at the inlet of each branch, and the water supply pressure at the outlet of each branch in S1 are obtained through pressure sensors arranged at corresponding positions; the opening of the main pipe inlet regulating valve, the opening of the main pipe outlet regulating valve, the opening of the inlet regulating valve of each branch, and the opening of the outlet regulating valve of each branch are obtained through displacement sensors arranged at corresponding positions.

[0059] In some embodiments, the spray rack inlet pressure P in S2 is r for:

[0060] P r =P b -ΔP m

[0061] Among them, P b is the pump outlet pressure; ΔP m Local and along-the-way pressure loss of the main road.

[0062] In some embodiments, in S3, the pressure P at the front end of the i-th spray rake inlet regulating valve is ri for:

[0063] P ri =P r -ΔP mri -P hri

[0064] Among them, ΔP mri is the pressure loss from the spray rack inlet to the front end of the regulating valve at the i-th rake inlet; P hri is the pressure drop from the spray rack inlet to the i-th rake inlet regulating valve height difference. Since the spray rake height difference, internal pipe length, and number of accessories are the same, ΔP mri and P hri All of them change linearly, so it can be known that the front-end pressure of each spray rake inlet regulating valve is certain.

[0065] In some embodiments, the initial opening in S3 is not less than 15%. In order to improve the service life, stability, normal regulation and other working performance of the valve, the opening of the inlet regulating valve and the outlet regulating valve is in a suitable opening range, and the regulating valve should avoid working at a small opening.

[0066] In some embodiments, based on the nozzle characteristics: when the nozzle air pressure is constant, different nozzle water supply pressures correspond to different nozzle water flow rates. In S3, the flow loss on the branch is the flow loss on the spray rake set on the branch, so the total flow loss Q on the spray rake is t for:

[0067] Q t =Q w *n

[0068] Among them, Q w is the water flow rate of a single nozzle, and n is the number of nozzles on the spray rake.

[0069] In some embodiments, the preset opening of the spray rake outlet regulating valve is calculated according to the valve flow characteristics.

[0070] Maximum flow rate Q controlled by the valve max With minimum flow Q min The ratio is called the adjustable ratio and is represented by R:

[0071]

[0072] The regulating valves involved in this system all have equal percentage characteristics, namely:

[0073]

[0074] Where Q is the current valve flow, L / L max is the relative opening of the valve.

[0075] According to the above valve flow characteristics, adjust the spray rake outlet regulating valve opening to affect the nozzle loss flow Q t After compensation, the valve flow rate is:

[0076] Q f =QQ t

[0077] Preset opening of spray rake outlet valve V o for:

[0078]

[0079] In some embodiments, in S6, the opening of the regulating valve at the outlet of each branch spray rake is fine-tuned by a single neuron adaptive controller.

[0080] In some embodiments, the adjustment of the weight coefficient is implemented according to the supervised Hebb learning rule, and the control algorithm and the learning algorithm are as follows:

[0081]

[0082]

[0083] w 1 (k) = w 1 (k-1)+η I z(k)u(k)(e(k)+Δe(k))

[0084] w 2 (k) = w 2 (k-1)+η P z(k)u(k)(e(k)+Δe(k))

[0085] w 3 (k) = w 3 (k-1)+η D z(k)u(k)(e(k)+Δe(k))

[0086] In the formula, x 1 (k) = e(k); x 2 (k) = e(k) - e(k-1); x 3 (k) = e(k) - 2e(k - 1) + e(k - 2);

[0087] z(k)=e(k);η I , η P , η D are the learning rates of integration, proportion, and differentiation respectively; K is the proportional coefficient of the neuron, K>0,

[0088] Among them, e(k) is the difference between the pressure setting value and the sampling value at the current moment, e(k-1) is the difference between the pressure setting value and the sampling value at the previous moment, and e(k-2) is the difference between the pressure setting value and the sampling value at the moment before that.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. The above description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present invention. These improvements and variations should also be regarded as the protection scope of the present invention.

Claims

1. A burst-coupling adaptive control method for an array of independently controllable nozzles, characterized in that: The method comprises the following steps: S1: Collect the water supply pressure at the main pipe inlet, the water supply pressure at the main pipe outlet, the water supply pressure at the inlet of each branch, the water supply pressure at the outlet of each branch, the opening of the main pipe inlet regulating valve, the opening of the main pipe outlet regulating valve, the opening of the inlet regulating valve of each branch and the opening of the outlet regulating valve of each branch; S2: Let the water pump run at a constant speed, and the main return water regulating valve is closed-loop controlled to keep the inlet pressure of the water supply main constant; S3: When the inlet pressure of the s2 water supply main is kept constant, adjust the inlet regulating valve and outlet regulating valve of each branch so that the opening of the inlet regulating valve and outlet regulating valve is at the initial opening, fix the opening of each branch outlet regulating valve, close the loop to adjust the opening of each branch inlet regulating valve, and fix the opening of each branch inlet regulating valve after the pressure in each branch is stable; S4: Based on the pressure inside the rake of each branch obtained in S3 and the nozzle characteristics under the current working conditions, the flow loss on the branch is calculated; S5: According to the flow loss calculated in S4, the opening of each branch outlet regulating valve is preset for rough adjustment; S6: Based on the coarse adjustment of S5, enter the closed-loop control to fine-tune the outlet regulating valves of each branch to quickly stabilize the pressure of each branch within 10 seconds.

2. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 1 is characterized in that: The water supply pressure at the main pipe inlet, the water supply pressure at the main pipe outlet, the water supply pressure at the inlet of each branch and the water supply pressure at the outlet of each branch in S1 are obtained through pressure sensors arranged at corresponding positions; the opening of the main pipe inlet regulating valve, the opening of the main pipe outlet regulating valve, the opening of the inlet regulating valve of each branch and the opening of the outlet regulating valve of each branch are obtained through displacement sensors arranged at corresponding positions.

3. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 1 is characterized in that: The spray rack inlet pressure P in S2 r for: Among them, P b is the pump outlet pressure; ΔP m It is the pressure loss between the pump outlet and the water supply main inlet.

4. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 3 is characterized in that: In S3, the pressure P at the front end of the i-th spray rake inlet regulating valve ri for: Among them, ΔP mri is the pressure loss from the spray rack inlet to the front end of the regulating valve at the i-th rake inlet; P hri is the pressure drop due to the height difference of the regulating valve from the spray rack inlet to the i-th rake inlet.

5. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 1, characterized in that: The initial opening of S3 is not less than 15%.

6. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 1, characterized in that: In S3, the flow loss on the branch is the flow loss on the spray rake arranged on the branch, so the total flow loss Q on the spray rake is t for: Among them, Q w is the water flow rate of a single nozzle, and n is the number of nozzles on the spray rake.

7. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 5, characterized in that: In S5, the opening of each branch outlet regulating valve is preset V o for: Among them, R is the maximum flow rate of the valve Q max With minimum flow Q min The ratio, Q f is the valve flow after compensation, Q is the current valve flow, Among them, the compensated valve flow Q f for: ， Q t It is the flow rate lost by the nozzle due to the opening of the spray rake outlet regulating valve.

8. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 6, characterized in that: In S6, the opening of the regulating valve at the outlet of each branch spray rake is fine-tuned by a single neuron adaptive controller.

9. The burst-coupling adaptive control method of an array of independently controllable nozzles according to claim 8, characterized in that: The adjustment of weight coefficients is implemented according to the supervised Hebb learning rule. The control algorithm and learning algorithm are as follows: in, ； ； ； ； are the learning rates of integration, proportion, and differentiation respectively; K is the proportional coefficient of the neuron, , in, is the difference between the current pressure setting value and the sampled value. is the difference between the pressure setting value and the sampling value at the previous moment. is the difference between the pressure setting value and the sampling value at the previous moment. μ(k) is the control signal at the current moment, is the control signal at the previous moment; ; The weight coefficient corresponding to the integral I, The weight coefficient corresponding to the proportion P; The weight coefficient corresponding to the differential D.

Images