Refrigeration systems and their control methods, devices, air conditioning, media and process products

Abstract

This invention discloses a refrigeration system and its control method, device, air conditioner, storage medium, and computer program product. The refrigeration system has a throttling device, which includes a first throttling element and a second throttling element arranged in parallel. The opening degree of the first throttling element can be adjusted. The method includes: controlling the second throttling element to open or close according to the target opening degree of the first throttling element; and adjusting the actual operating opening degree of the first throttling element based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element when the second throttling element is closed, in conjunction with the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element. This solution, by controlling the second throttling element to open or close according to the target opening degree of the first throttling element, and dynamically adjusting the opening degree of the first throttling element according to the outdoor ambient temperature and the inlet pressure of the first throttling element, avoids the sudden change in refrigerant flow rate caused by the opening of the first throttling element being too large or too small, which would cause noise (such as whistling), thus improving the user experience.

Description

Technical Field

[0001] This invention belongs to the field of refrigeration system technology, specifically relating to a control method, device, refrigeration system, air conditioner, storage medium, and computer program product for a refrigeration system, and particularly to a method, device, refrigeration system, air conditioner, storage medium, and computer program product for controlling the opening of an expansion valve based on dynamic pressure sensing and nonlinear correction in a refrigeration system. Background Technology

[0002] In refrigeration systems, throttling devices (such as expansion valves, preferably electronic expansion valves) are key throttling elements, and the opening control of the expansion valve directly affects the operating efficiency and stability of the refrigeration system. In the opening control of throttling devices (such as expansion valves, preferably electronic expansion valves), if the opening of the expansion valve is too large or too small, the sudden change in flow velocity during refrigerant circulation will cause noise (such as whistling), affecting the user experience.

[0003] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The purpose of this invention is to provide a control method, device, refrigeration system, air conditioner, storage medium, and computer program product for a refrigeration system. This addresses the problem that in the control of the opening of a throttling device (such as an expansion valve, preferably an electronic expansion valve), if the opening of the expansion valve is too large or too small, noise (such as a whistling sound) will occur due to sudden changes in refrigerant velocity during refrigerant flow, affecting the user experience. The invention achieves this by setting a parallel throttling structure of a first throttling element (such as an expansion valve) and a second throttling element (such as a one-way pipe) in the throttling device of the refrigeration system. The second throttling element is controlled to open or close according to the target opening of the first throttling element, and the opening of the first throttling element is dynamically adjusted according to the outdoor ambient temperature and the pressure at the front end of the first throttling element. This avoids sudden changes in refrigerant velocity caused by excessively large or small openings of the first throttling element, thus improving the user experience.

[0005] This invention provides a control method for a refrigeration system, the refrigeration system having a throttling device; the throttling device includes: a first throttling element and a second throttling element, the opening degree of the first throttling element being adjustable, and the first throttling element and the second throttling element being connected in parallel; the control method for the refrigeration system includes: controlling the second throttling element to open or close according to a target opening degree of the first throttling element; acquiring the outdoor ambient temperature of the refrigeration system and acquiring the inlet pressure of the first throttling element; when the second throttling element is controlled to close, adjusting the actual operating opening degree of the first throttling element in combination with the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element.

[0006] In some embodiments, the first throttling element includes an expansion valve; the second throttling element includes a one-way pipe; wherein, in the refrigerant flow direction of the refrigeration system, the inlet of the expansion valve is connected to the inlet of the one-way pipe, and the outlet of the expansion valve is connected to the outlet of the one-way pipe.

[0007] In some implementations, controlling the second throttling element to be turned on or off based on the target opening degree of the first throttling element includes: determining whether the target opening degree of the first throttling element is greater than or equal to a preset opening degree threshold; if the target opening degree of the first throttling element is determined to be greater than or equal to the preset opening degree threshold, then controlling the second throttling element to be turned off; if the target opening degree of the first throttling element is determined to be less than the preset opening degree threshold, then controlling the second throttling element to be turned on.

[0008] In some embodiments, adjusting the actual operating opening of the first throttling element by combining the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element includes: determining whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold; if it is determined that the inlet pressure of the first throttling element is greater than or equal to the preset pressure threshold, then determining a correction value for the opening of the first throttling element based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element; and adjusting the target opening of the first throttling element based on the correction value, which is taken as the actual operating opening of the first throttling element.

[0009] In some embodiments, determining the opening correction value of the first throttling element based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element includes: determining the difference between the outdoor ambient temperature of the refrigeration system and a preset temperature threshold, denoted as the outdoor temperature difference of the refrigeration system; and determining the difference between the inlet pressure of the first throttling element and a preset pressure threshold, denoted as the inlet pressure difference of the first throttling element; if the outdoor ambient temperature of the refrigeration system is determined to be greater than the preset temperature threshold, determining the product of a preset pressure coefficient and the inlet pressure difference of the first throttling element as a first product value, determining the product of a preset heat load coefficient and the outdoor temperature difference of the refrigeration system as a second product value, and determining the sum of the first product value and the second product value as the opening correction value of the first throttling element; if the outdoor ambient temperature of the refrigeration system is determined to be less than or equal to the preset temperature threshold, determining the product of a preset pressure coefficient and the inlet pressure difference of the first throttling element as a first product value, which is used as the opening correction value of the first throttling element.

[0010] And / or, based on the opening correction value of the first throttling element, adjust the target opening of the first throttling element as the actual operating opening of the first throttling element, including: determining the difference between the target opening of the first throttling element and the opening correction value of the first throttling element as the actual operating opening of the first throttling element; so as to: control the first throttling element to operate at the actual operating opening of the first throttling element, return after a set time, so as to re-determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold.

[0011] In some embodiments, adjusting the actual operating opening of the first throttling element by combining the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element further includes: determining whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold; if it is determined that the inlet pressure of the first throttling element is less than the preset pressure threshold, then the target opening of the first throttling element is taken as the actual operating opening of the first throttling element; so as to control the first throttling element to operate at the actual operating opening of the first throttling element, return after a set time, and re-determine whether the inlet pressure of the first throttling element is greater than or equal to the preset pressure threshold.

[0012] In conjunction with the above method, another aspect of the present invention provides a control device for a refrigeration system, comprising: a control unit configured to control a second throttling element to be turned on or off according to a target opening degree of the first throttling element; an acquisition unit configured to acquire the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element; the control unit is further configured to, when controlling the second throttling element to be turned off, adjust the actual operating opening degree of the first throttling element in combination with the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element.

[0013] In conjunction with the above-described device, the present invention further provides a refrigeration system, comprising: a control device for the refrigeration system described above.

[0014] In conjunction with the above-described device, the present invention further provides an air conditioner, comprising: a control device for the refrigeration system described above, or the refrigeration system described above.

[0015] In conjunction with the above method, the present invention further provides a storage medium comprising a stored program, wherein, when the program is executed, the device containing the storage medium is controlled to perform the steps of the control method of the refrigeration system described above.

[0016] In conjunction with the above method, the present invention further provides a computer program product, including a computer program that, when executed by a processor, implements the steps of the control method for the refrigeration system described above.

[0017] The present invention addresses a throttling device in a refrigeration system (such as an air conditioner). The throttling device includes a first throttling element and a second throttling element connected in parallel. The opening degree of the first throttling element is adjustable. The second throttling element is controlled to open or close based on the target opening degree of the first throttling element. The outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element are obtained. When the second throttling element is controlled to close, the actual operating opening degree of the first throttling element is adjusted based on the outdoor ambient temperature and the inlet pressure of the first throttling element. Therefore, by setting a parallel throttling structure of a first throttling element (such as an expansion valve) and a second throttling element (such as a one-way pipe) in the throttling device of the refrigeration system, the second throttling element is controlled to open or close based on the target opening degree of the first throttling element, and the opening degree of the first throttling element is dynamically adjusted based on the outdoor ambient temperature and the pressure at the front end of the first throttling element, thus avoiding sudden changes in refrigerant flow rate and noise (such as whistling) caused by excessively large or small opening of the first throttling element, thereby improving the user experience.

[0018] Specifically, in the solution of this invention, for the throttling device in a refrigeration system (such as an air conditioner), a parallel throttling structure of an expansion valve and a one-way pipe is set; when the target throttling opening of the expansion valve in the refrigeration system (such as the calculated opening of the expansion valve) is greater than or equal to a preset opening threshold (such as 100B), the one-way pipe is controlled to close for the parallel throttling structure, so that the expansion valve throttles independently, and the opening of the expansion valve is dynamically adjusted in combination with the inlet pressure of the expansion valve in the refrigerant flow direction (such as the front end pressure of the expansion valve) and the outdoor ambient temperature: when the outdoor ambient temperature is higher than the preset temperature threshold, such as 35°C, the opening correction value △B = a*△P + b*△T is determined, and the actual operating opening of the expansion valve B2 = the calculated opening of the expansion valve B1 - the opening correction value △B, where △B is the opening correction value. Positive values ​​are defined as follows: 'a' is the pressure coefficient, 'ΔP' is the difference between the current pressure and the preset pressure of the refrigeration system, 'b' is the heat load coefficient, and 'ΔT' is the difference between the outdoor ambient temperature and the preset high load temperature. When the target throttling opening of the expansion valve in the refrigeration system (e.g., the calculated opening of the expansion valve) is less than the preset opening threshold (e.g., 100B), the one-way valve is opened for this parallel throttling structure, allowing the expansion valve and the one-way pipe to throttle in parallel. Thus, by setting a parallel throttling structure of the expansion valve and the one-way pipe in the throttling device of the refrigeration system, the one-way pipe is opened or closed according to the target opening of the expansion valve, and the opening of the expansion valve is dynamically adjusted according to the outdoor ambient temperature and the pressure at the front end of the expansion valve. This avoids the expansion valve opening being too large or too small, which could cause a sudden change in refrigerant flow rate and generate noise (e.g., whistling), thus improving the user experience.

[0019] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention.

[0020] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0021] Figure 1 This is a flowchart illustrating an embodiment of the control method for the refrigeration system of the present invention;

[0022] Figure 2 This is a flowchart illustrating an embodiment of the method of the present invention for controlling the second throttling element to be turned on or off;

[0023] Figure 3 This is a flowchart illustrating an embodiment of adjusting the target opening of the first throttling element in the method of the present invention;

[0024] Figure 4 This is a flowchart illustrating an embodiment of the method of the present invention for determining the opening correction value of the first throttling element;

[0025] Figure 5 This is a flowchart illustrating an embodiment of adjusting the target opening of the first throttling element in the method of the present invention, which serves as the actual operating opening of the first throttling element.

[0026] Figure 6 This is a flowchart illustrating an embodiment of the method of the present invention for maintaining the target opening degree of the first throttling element;

[0027] Figure 7 This is a schematic diagram of the structure of a control device for the refrigeration system of the present invention;

[0028] Figure 8 This is a schematic diagram of the refrigeration system.

[0029] Figure 9 This is a flowchart illustrating the expansion valve opening control method based on dynamic pressure sensing and nonlinear correction in a refrigeration system.

[0030] Referring to the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows:

[0031] 1-Compressor; 2-Liquid tank; 3-Four-way valve; 4-Indoor heat exchanger; 5-Electronic expansion valve; 6-One-way pipe; 7-Outdoor heat exchanger; 102-Acquisition unit; 104-Control unit. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0033] Considering that in the opening control of throttling devices (such as expansion valves, preferably electronic expansion valves), if the opening of the expansion valve is too large or too small, the sudden change in flow velocity during refrigerant flow will cause noise (such as whistling), affecting the user experience, related solutions often use fixed proportional control or linear feedback control methods to control the opening of throttling devices (such as expansion valves, preferably electronic expansion valves), which cannot dynamically adjust the opening in real time according to changes in refrigeration system pressure (i.e., pressure at the front end of the expansion valve). Under high temperature and high pressure conditions, throttling devices (such as expansion valves, preferably electronic expansion valves) typically have a large opening. When the expansion valve opening is too large, the refrigerant flows through the flared end of the expansion valve, and the flow velocity increases sharply due to the sudden contraction of the flow channel area. This can easily cause a sudden drop in pressure. When the pressure is lower than the saturated vapor pressure of the refrigerant, bubbles will form inside the liquid, thus causing a whistling sound. Under low load conditions, throttling devices (such as expansion valves, preferably electronic expansion valves) typically have a small opening. When the expansion valve opening is too small, excessive throttling and the formation of a narrow flow channel at the valve needle can also cause a whistling sound due to the sudden increase in flow velocity.

[0034] Furthermore, the opening control method of the throttling device (preferably an electronic expansion valve) in the relevant schemes does not consider the nonlinear coupling effect between the outdoor ambient temperature and the refrigeration system pressure (i.e., the pressure at the front end of the expansion valve), resulting in low control accuracy. Specifically, in the relevant schemes, the opening control of the throttling device (preferably an electronic expansion valve) adopts a fixed proportional linear control method. The opening of the expansion valve is determined based on the difference between the compressor's discharge temperature and the target discharge temperature. When the compressor's discharge temperature is lower than the target discharge temperature, the expansion valve opening is reduced; when the compressor's discharge temperature is higher than the target discharge temperature, the expansion valve opening is increased until the compressor's discharge temperature meets the target discharge temperature. In this process, factors such as the outdoor ambient temperature and the refrigeration system pressure (i.e., the pressure at the front end of the expansion valve) are not considered. Therefore, the problem of a sudden pressure drop caused by the refrigerant flowing through the flare opening when the expansion valve opening is too large or too small, resulting in a whistling sound, cannot be ruled out. Therefore, the opening control accuracy of the expansion valve is not high.

[0035] Therefore, the present invention proposes a control method for a refrigeration system, specifically a method for controlling the opening of an expansion valve in a refrigeration system based on dynamic pressure sensing and nonlinear correction. Based on the real-time pressure feedback mechanism of the pressure sensor, the opening of the expansion valve is dynamically adjusted to maintain the refrigeration system pressure (i.e., the pressure at the front end of the expansion valve) within a stable range. This avoids the expansion valve opening being too large or too small, which could cause noise (such as whistling) due to sudden changes in flow velocity during refrigerant flow, thus affecting the user experience.

[0036] According to embodiments of the present invention, a control method for a refrigeration system is provided, such as... Figure 1 The diagram shows a flow chart of an embodiment of the method of the present invention. The refrigeration system has a throttling device for adjusting the refrigerant flow rate; for example, in the case of an air conditioner, a throttling device is provided between the outdoor heat exchanger and the indoor heat exchanger of the air conditioner; the throttling device includes: a first throttling element and a second throttling element, the opening degree of the first throttling element being adjustable, and the first throttling element and the second throttling element being arranged in parallel; the first throttling element is as follows: Figure 8 The expansion valve shown has a second throttling element as... Figure 8 The unidirectional tube shown. In the solution of the present invention, as... Figure 1 As shown, the control method of the refrigeration system includes steps S110 to S130.

[0037] In step S110, the second throttling element is controlled to turn on or off according to the target opening degree of the first throttling element; wherein, the target opening degree of the first throttling element is pre-calculated based on the opening degree coefficient of the first throttling element and the system parameters of the refrigeration system; after the refrigeration system is turned on, the target opening degree of the first throttling element is determined. The target opening degree of the first throttling element is as follows: Figure 8 The expansion valve shown is used to calculate its opening degree.

[0038] The calculated opening degree of the expansion valve is obtained by calculating the opening coefficient and system parameters, and this calculated opening degree serves as the target opening degree for the expansion valve. This calculation can be performed using techniques known in the air conditioning industry. For example: P = A*f + B*T 外环 +C*T 内环 +D. P is the calculated opening degree of the expansion valve, f is the compressor operating frequency; A, B, C, and D are opening coefficients and are natural numbers, such as A, B, C, and D being 1, 2, 1, and 30 respectively; when the inner ring temperature T 内环 The ambient temperature is 20℃, and the outer ring temperature is T. 外环 When the temperature is 30℃ and the compressor operating frequency is f=50Hz, the calculated opening degree of the expansion valve is P=A*f+B*T. 外环 +C*T 内环+D=1*50+2*30+1*20+30=160B (steps), then the calculated opening degree of the expansion valve is 160B. The dimensions on both sides of the equation in this formula are consistent; only the calculated value is considered, not the unit.

[0039] In step S120, while controlling the second throttling element to turn off, the outdoor ambient temperature of the refrigeration system is acquired, and the inlet pressure of the first throttling element is acquired; wherein, the inlet pressure of the first throttling element is the pressure at the front end of the first throttling element in the refrigerant flow direction of the refrigeration system. The inlet pressure of the first throttling element is as follows: Figure 8 The pressure at the front end of the expansion valve is shown. The outdoor ambient temperature of the refrigeration system is obtained, such as the outdoor ambient temperature collected in real time by a temperature sensor; the inlet pressure of the first throttling element is obtained, such as the pressure at the front end of the expansion valve collected in real time by a pressure sensor.

[0040] In step S130, when the second throttling element is turned off, the actual operating opening of the first throttling element is adjusted based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element, so that the pressure of the refrigeration system is maintained in a stable range. Of course, when the second throttling element is turned on, the actual operating opening of the first throttling element is the sum of the target opening of the first throttling element and the opening of the second throttling element, which can also maintain the pressure of the refrigeration system in a stable range.

[0041] In the present invention, by setting a parallel throttling structure of a first throttling element (such as an expansion valve) and a second throttling element (such as a one-way pipe) in the throttling device of the refrigeration system, the second throttling element is controlled to open or close according to the target opening degree of the first throttling element, and the opening degree of the first throttling element is dynamically adjusted according to the outdoor ambient temperature and the pressure at the front end of the first throttling element, so as to avoid the refrigerant flow rate from changing suddenly due to the opening of the first throttling element being too large or too small, which would cause noise (such as whistling sound) and improve the user experience.

[0042] The present invention proposes an expansion valve opening control scheme based on dynamic pressure sensing and nonlinear correction in a refrigeration system. Based on the real-time pressure feedback mechanism of the pressure sensor, the expansion valve opening is dynamically adjusted, so that the refrigeration system pressure (i.e., the pressure at the front end of the expansion valve) is maintained in a stable range. This can effectively avoid the formation of bubbles and whistling sound caused by excessive refrigerant flow rate, reduce noise, and improve user experience.

[0043] In some embodiments, the first throttling element includes an expansion valve; the second throttling element includes a one-way pipe; the expansion valve is as follows: Figure 8 The electronic expansion valve 5 shown, the one-way tube as... Figure 8The one-way pipe 6 is shown. In the refrigerant flow direction of the refrigeration system, the inlet of the expansion valve is connected to the inlet of the one-way pipe, and the outlet of the expansion valve is connected to the outlet of the one-way pipe.

[0044] For example, Figure 8 This is a schematic diagram of the refrigeration system, such as... Figure 8 The refrigeration system shown includes: a compressor 1, a liquid receiver 2, a four-way valve 3, an indoor heat exchanger 4, an expansion valve (such as an electronic expansion valve 5), a one-way pipe 6, and an outdoor heat exchanger 7. The discharge port of the compressor 1 is connected to the first port of the four-way valve 3; the second port of the four-way valve 3, after passing through the indoor heat exchanger 4, the second port of the electronic expansion valve 5, the first port of the electronic expansion valve 5, and the outdoor heat exchanger 7, is connected to the fourth port of the four-way valve 3; the third port of the four-way valve 3, after passing through the liquid receiver 2, returns to the suction port of the compressor 1. The one-way pipe 6 is connected in parallel with the electronic expansion valve 5, with its inlet connected to the second port of the electronic expansion valve 5 and its outlet connected to the first port of the electronic expansion valve 5.

[0045] In the solution of the present invention, the expansion valve is dynamically switched between individual throttling mode and parallel throttling mode with one-way pipe based on the calculated opening size of the expansion valve, thereby improving the adaptability and stability of the refrigeration system.

[0046] In some implementations, the specific process of controlling the second throttling element to turn on or off according to the target opening degree of the first throttling element in step S110 is described in the following exemplary description.

[0047] The following is combined with Figure 2 The flowchart of an embodiment of the method of the present invention for controlling the second throttling element to be turned on or off is shown. The specific process of controlling the second throttling element to be turned on or off in step S110 is further explained, including steps S210 to S230.

[0048] Step S210: Determine whether the target opening degree of the first throttling element is greater than or equal to a preset opening degree threshold; wherein, the preset opening degree threshold is, for example, 100B.

[0049] Step S220: If it is determined that the target opening degree of the first throttling element is greater than or equal to the preset opening degree threshold, then the second throttling element is controlled to turn off.

[0050] Step S230: If it is determined that the target opening degree of the first throttling element is less than the preset opening degree threshold, then control the second throttling element to turn on.

[0051] This invention proposes a control scheme for the opening of an expansion valve in a refrigeration system based on dynamic pressure sensing and nonlinear correction. This scheme is applicable to the throttling control of the expansion valve in a refrigeration system. The refrigeration system includes a pressure sensor, an expansion valve, a check pipe, and a controller. The expansion valve and the check pipe are connected in parallel. When the expansion valve opening is less than 100B (steps), the check pipe is open, and the expansion valve and check pipe throttle in parallel. When the expansion valve opening is greater than or equal to 100B, the check pipe is closed, and the expansion valve throttles independently. The refrigeration system refers to a complete system composed of multiple key components capable of completing a "heat absorption-compression-heat release-throttling" cycle to achieve continuous cooling. A refrigeration system is not simply a refrigeration cycle; heating cycles are also an application of refrigeration systems. It is commonly used in air conditioning, refrigerators, cold storage, and industrial cooling and heating.

[0052] In the present invention, the expansion valve opening control method based on dynamic pressure sensing and nonlinear correction in the refrigeration system includes: the refrigeration system (such as an air conditioner) is started and running; a pressure sensor collects pressure data at the front end of the expansion valve in real time; and then it is determined whether the expansion valve opening (i.e., the calculated opening of the expansion valve) is greater than or equal to a preset opening threshold, such as 100B.

[0053] If the expansion valve opening (i.e., the calculated expansion valve opening) is greater than or equal to a preset opening threshold, such as 100B, the refrigeration system enters the expansion valve-only throttling mode, with the check valve closed or in a non-operating state. In other words, when the controller calculates that the expansion valve opening is greater than or equal to 100B based on the opening coefficient and system parameters, the refrigeration system enters the "expansion valve-only throttling" mode. At this time, the check valve is closed or in a non-operating state, and only the expansion valve performs throttling control.

[0054] If the expansion valve opening (i.e., the calculated expansion valve opening) is less than 100B, the check pipe opens, and the expansion valve and check pipe are connected in parallel for throttling. When the expansion valve opening (i.e., the calculated expansion valve opening) is less than a preset opening threshold such as 100B, the expansion valve opening (i.e., the calculated expansion valve opening) is recorded as the calculated expansion valve opening B3, and the actual operating opening of the expansion valve is recorded as the actual operating expansion valve opening B4. The check pipe maintains constant throttling, and the actual operating expansion valve opening B4 = calculated expansion valve opening B3 + constant check pipe opening ΔB1. This improves the control accuracy of the expansion valve under complex operating conditions and avoids pressure surges and whistling sounds caused by excessive throttling. For example, if the constant check pipe opening ΔB1 = 30B, when the calculated expansion valve opening B3 = 60B, the actual operating expansion valve opening B4 = 60 + 30 = 90 (B).

[0055] When the expansion valve opening calculated by the controller is less than 100B, the refrigeration system switches to the "expansion valve and check pipe parallel throttling" mode. In this mode, the check pipe maintains a constant throttling (e.g., the calculated opening ΔB1 of the check pipe is 30B), and the actual throttling opening B4 of the expansion valve = calculated opening B3 + ΔB1. The overall throttling effect of the refrigeration system remains unchanged, while avoiding excessive throttling of the expansion valve at low openings (when the expansion valve opening is too small, excessive throttling, the formation of a narrow flow channel at the valve needle, and a sudden increase in flow velocity can also cause a whistling sound), thus improving the stability and reliability of the refrigeration system.

[0056] In the solution of this invention, the expansion valve throttling mode is dynamically switched according to the calculated opening size of the expansion valve, thereby improving the stability and adaptability of the system operation.

[0057] In some implementations, step S130, which combines the outdoor ambient temperature of the refrigeration system with the inlet pressure of the first throttling element to adjust the actual operating opening of the first throttling element, includes the process of adjusting the target opening of the first throttling element.

[0058] The following is combined with Figure 3 The flowchart shown is a schematic diagram of an embodiment of the method of the present invention for adjusting the target opening of the first throttling element. It further illustrates the specific process of adjusting the target opening of the first throttling element in step S130, including steps S310 to S330.

[0059] Step S310: Determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold; wherein, the preset pressure threshold is, for example, 3.0 MPa.

[0060] Step S320: If it is determined that the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold, then the opening correction value of the first throttling element is determined based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element.

[0061] Step S330: Adjust the target opening of the first throttling element according to the opening correction value of the first throttling element, and use it as the actual operating opening of the first throttling element.

[0062] In the embodiment of the present invention, the pressure sensor can be arranged at the front end of the expansion valve in the refrigerant flow direction of the refrigeration system, such as the pressure sensor being arranged at... Figure 8The second port of the electronic expansion valve 5 in the refrigeration system is shown. During the operation of the refrigeration system, the pressure sensor collects the pressure data at the front end of the expansion valve in real time and transmits the collected pressure data to the controller (such as an air conditioning controller). The controller dynamically adjusts the opening of the expansion valve according to the current pressure change trend at the front end of the expansion valve reflected by the pressure data, so as to ensure that the pressure of the refrigeration system (i.e., the pressure at the front end of the expansion valve) changes smoothly and avoids sudden pressure drops or rises.

[0063] In the solution of this invention, the nonlinear coupling effect of outdoor ambient temperature and pressure is combined to improve the control accuracy of the expansion valve; the technical problem of system instability caused by excessive throttling under low load conditions is solved (this reflects Bernoulli's principle), and the control accuracy of the expansion valve under complex conditions is improved.

[0064] In some embodiments, the specific process of determining the opening correction value of the first throttling element based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element in step S320 is described in the following exemplary description.

[0065] The following is combined with Figure 4 The flowchart shown is a schematic diagram of an embodiment of the method of the present invention for determining the opening correction value of the first throttling element. It further illustrates the specific process of determining the opening correction value of the first throttling element in step S320, including steps S410 to S430.

[0066] Step S410: Determine the difference between the outdoor ambient temperature of the refrigeration system and a preset temperature threshold, and record it as the outdoor temperature difference of the refrigeration system; and determine the difference between the inlet pressure of the first throttling element and a preset pressure threshold, and record it as the inlet pressure difference of the first throttling element; wherein, the outdoor ambient temperature of the refrigeration system is such as temperature Tn, the preset temperature threshold is such as temperature T0, the inlet pressure of the first throttling element is such as pressure Pn, and the preset pressure threshold is such as pressure P0; the outdoor temperature difference of the refrigeration system is such as ΔT = Tn - T0, and the inlet pressure difference of the first throttling element is such as ΔP = Pn - P0. The preset temperature threshold is such as 35℃.

[0067] Step S420: If the outdoor ambient temperature of the refrigeration system is determined to be greater than a preset temperature threshold, the product of the preset pressure coefficient and the inlet pressure difference of the first throttling element is recorded as the first product value, and the product of the preset heat load coefficient and the outdoor temperature difference of the refrigeration system is recorded as the second product value. The sum of the first product value and the second product value is then used as the opening correction value of the first throttling element. Here, the preset pressure coefficient is, for example, pressure coefficient a, and the preset heat load coefficient is, for example, heat load coefficient b.

[0068] Step S430: If the outdoor ambient temperature of the refrigeration system is determined to be less than or equal to a preset temperature threshold, the product of the preset pressure coefficient and the inlet pressure difference of the first throttling element is recorded as the first product value, which is used as the opening correction value of the first throttling element.

[0069] In the present invention, the expansion valve opening control method based on dynamic pressure sensing and nonlinear correction in the refrigeration system further includes:

[0070] Based on the pressure data of the expansion valve front end collected in real time by the pressure sensor, it is determined whether the expansion valve front end pressure is greater than or equal to the preset pressure threshold, such as 3.0 MPa. If it is determined that the expansion valve front end pressure is greater than or equal to the preset pressure threshold, such as 3.0 MPa, then under the condition that the outdoor ambient temperature is higher than the preset temperature threshold, such as 35℃, the expansion valve opening correction value △B is calculated by a nonlinear correction algorithm.

[0071] The opening correction value △B = a*△P + b*△T (1).

[0072] The calculation result of the expansion valve opening correction value △B is rounded to the nearest integer. The dimensions of both sides of formula (1) are consistent, and only numerical values ​​are considered during calculation. For example, the unit of a can be 1 / Mpa, the unit of △P can be Mpa, the unit of b can be 1 / ℃, and the unit of △T can be ℃. △B is the opening correction value, a is the pressure coefficient, △P is the difference between the current pressure of the refrigeration system and the preset pressure; b is the heat load coefficient, which is related to the outdoor ambient temperature; △T is the difference between the outdoor ambient temperature and the preset high load temperature. △P=Pn-P0, Pn is the current pressure of the refrigeration system (i.e., the pressure at the front end of the expansion valve detected by the front end of the expansion valve), P0 is the preset pressure; △T=Tn-T0, Tn is the outdoor ambient temperature, T0 is the preset high load temperature.

[0073] The nonlinear correction algorithm is mainly aimed at the fixed proportional linear control method in the relevant scheme. The control method in the relevant scheme determines whether the expansion valve opens or closes based on the difference between the exhaust temperature and the target exhaust temperature. The nonlinear correction algorithm takes into account the ambient temperature and system pressure, and does not add or subtract in a fixed proportion. Instead, it calculates the correction value based on the coupling of pressure difference and temperature difference, which is more accurate.

[0074] In the solution of this invention, a nonlinear correction algorithm and an opening correction value are introduced under high temperature and high pressure conditions to improve control accuracy.

[0075] In some embodiments, step S330 involves adjusting the target opening of the first throttling element based on the opening correction value of the first throttling element, which serves as the actual operating opening of the first throttling element. See the following exemplary description for details.

[0076] The following is combined with Figure 5 The flowchart shown is a schematic diagram of an embodiment of the method of the present invention, in which the target opening of the first throttling element is adjusted as the actual operating opening of the first throttling element. The specific process of adjusting the target opening of the first throttling element as the actual operating opening of the first throttling element in step S330 is further explained, including steps S510 to S520.

[0077] Step S510: Determine the difference between the target opening degree of the first throttling element and the opening degree correction value of the first throttling element, and use it as the actual operating opening degree of the first throttling element.

[0078] Step S520: Control the first throttling element to operate at its actual operating opening, return after a set time, and re-determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold, thereby dynamically adjusting the actual operating opening of the first throttling element.

[0079] In the present invention, the expansion valve opening control method based on dynamic pressure sensing and nonlinear correction in the refrigeration system further includes: when the expansion valve opening (i.e., the calculated expansion valve opening) is greater than or equal to a preset opening threshold such as 100B, the expansion valve opening (i.e., the calculated expansion valve opening) is recorded as the calculated expansion valve opening B1, and the actual operating opening of the expansion valve is recorded as the actual operating expansion valve opening B2. After determining the opening correction value ΔB = a*ΔP + b*ΔT, the actual operating expansion valve opening B2 = calculated expansion valve opening B1 - expansion valve opening correction value ΔB, to prevent the refrigerant flow rate in the expansion valve from being too fast, causing a sudden pressure drop and whistling sound. After a set time, the process returns to continue to determine whether the expansion valve front-end pressure is greater than or equal to a preset pressure threshold such as 3.0 MPa based on the real-time pressure data collected by the pressure sensor. Thus, based on the feedback of the real-time pressure data collected by the pressure sensor, the dynamic adjustment of the expansion valve opening is realized.

[0080] Assuming P0 = 3 MPa, T0 = 35℃, a = 15, b = 1, then: when the outdoor ambient temperature Tn is 40℃, the pressure Pn detected at the front end of the expansion valve is 3.5 MPa, and the opening degree of the expansion valve (i.e., the calculated opening degree of the expansion valve) is 450B, then △B = 15 * (3.5 - 3) + 1 * (40 - 35) = 13 (B); that is, the actual operating opening degree B2 = 450 - 13 = 437 (B).

[0081] Under high temperature and high pressure conditions, the controller calculates the expansion valve opening correction value △B = a*△P + b*△T based on the current outdoor ambient temperature and system pressure using a nonlinear correction algorithm. The actual operating opening of the expansion valve is B2 = B1 - △B. For example, under high temperature and high pressure conditions, when the pressure detected at the front end of the expansion valve is ≥3.0 MPa and the outdoor ambient temperature is higher than 35℃, the controller calculates the correction value △B based on the current outdoor ambient temperature and system pressure using a nonlinear correction algorithm. The actual operating opening of the expansion valve is B2 = calculated opening B1 - correction value △B, thereby limiting the refrigerant flow and preventing excessive refrigerant velocity from causing a sudden pressure drop and whistling sound (Law of conservation of mass: when the internal structure of the valve body remains unchanged, the greater the refrigerant flow, the higher the velocity; when the refrigerant flows through the flared opening inside the expansion valve, the flow channel area suddenly contracts and the velocity increases sharply, which easily causes a sudden pressure drop. When the pressure is lower than the saturated vapor pressure of the refrigerant, bubbles will form inside the liquid, thus causing a whistling sound).

[0082] In the solution of this invention, the pressure of the refrigeration system (i.e., the pressure at the front end of the expansion valve) is collected in real time by a pressure sensor, and the opening of the expansion valve is dynamically adjusted to keep the pressure of the refrigeration system (i.e., the pressure at the front end of the expansion valve) within a stable range. This can effectively avoid the formation of bubbles and whistling sound caused by excessive refrigerant flow rate. It also solves the problem of excessive refrigerant flow rate and whistling sound caused by excessive expansion valve opening (maximum opening when fully open) under high temperature and high pressure conditions (this reflects the law of conservation of mass).

[0083] In some embodiments, step S130, which combines the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element to adjust the actual operating opening of the first throttling element, also includes the process of maintaining the target opening of the first throttling element.

[0084] The following is combined with Figure 6 The schematic diagram shown is a flowchart of an embodiment of the method of the present invention for maintaining the target opening of the first throttling element. It further illustrates the specific process of maintaining the target opening of the first throttling element in step S130, including steps S610 to S630.

[0085] Step S610: Determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold; wherein, the preset pressure threshold is, for example, 3.0 MPa.

[0086] Step S620: If it is determined that the inlet pressure of the first throttling element is less than the preset pressure threshold, then the target opening of the first throttling element is taken as the actual operating opening of the first throttling element.

[0087] Step S630: Control the first throttling element to operate at its actual operating opening, return after a set time, and re-determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold, thereby dynamically adjusting the actual operating opening of the first throttling element.

[0088] For example, such as Figure 9 As shown, the expansion valve opening control method based on dynamic pressure sensing and nonlinear correction in the refrigeration system also includes:

[0089] Based on the real-time pressure data of the expansion valve front end collected by the pressure sensor, it is determined whether the pressure of the expansion valve front end is greater than or equal to a preset pressure threshold, such as 3.0 MPa. If it is determined that the pressure of the expansion valve front end is less than 3.0 MPa, then no matter how the outdoor ambient temperature changes, the opening of the expansion valve will not be corrected, that is, the expansion valve opening correction value ΔB = 0, which means that the pressure of the refrigeration system can be maintained in a stable range.

[0090] When the expansion valve opening (i.e., the calculated expansion valve opening) is greater than or equal to a preset opening threshold, such as 100B, the expansion valve opening (i.e., the calculated expansion valve opening) is recorded as the calculated expansion valve opening B1, and the actual operating opening of the expansion valve is recorded as the actual operating expansion valve opening B2. After determining that the opening correction value △B=0, the actual operating expansion valve opening B2 = calculated expansion valve opening B1 - expansion valve opening correction value △B, to prevent excessively fast refrigerant flow in the expansion valve from causing a sudden pressure drop and whistling sound. After a set time, the process returns to continue to determine whether the expansion valve front-end pressure is greater than or equal to a preset pressure threshold, such as 3.0Mpa, based on the real-time feedback of the expansion valve front-end pressure data collected by the pressure sensor. Thus, the expansion valve opening is dynamically adjusted based on the feedback of the real-time expansion valve front-end pressure data collected by the pressure sensor.

[0091] For example, Figure 9 This is a flowchart illustrating a method for controlling the opening of an expansion valve in a refrigeration system based on dynamic pressure sensing and nonlinear correction. Figure 9 As shown, the expansion valve opening control method based on dynamic pressure sensing and nonlinear correction in the refrigeration system includes:

[0092] Step 1: The refrigeration system (such as an air conditioner) is turned on and running. The pressure sensor collects the pressure data at the front end of the expansion valve in real time, and then proceeds to Step 2.

[0093] Step 2: Determine whether the expansion valve opening (i.e., the calculated opening of the expansion valve) is greater than or equal to the preset opening threshold, such as 100B. If yes, proceed to step 3; otherwise, proceed to step 4.

[0094] Of course, since the calculation of the expansion valve opening (i.e., the calculated opening of the expansion valve) is first determined to be greater than or equal to the preset opening threshold, such as 100B, the determination can be performed first, and then the pressure sensor can be used to collect the pressure data at the front end of the expansion valve in real time. The calculated opening of the expansion valve refers to the target opening of the expansion valve in the parallel structure of the expansion valve and the check pipe.

[0095] Step 3: If it is determined that the expansion valve opening (i.e., the calculated opening of the expansion valve) is greater than or equal to the preset opening threshold such as 100B, the refrigeration system enters the expansion valve individual throttling mode, the one-way pipe is closed or the one-way pipe is in a non-working state, and then step 31 is executed.

[0096] Among them, the check valve, such as the spring-loaded check valve, can be selected, for example, the K100 series (Danfoss) spring-loaded check valve. For the spring-loaded check valve, when in the forward direction, the pressure overcomes the spring force, pushing the valve disc open and allowing fluid to pass through; when in the reverse direction, the spring presses the valve disc back to the valve seat, achieving sealing and closure. The check valve is in the non-working state, that is, in the closed state. The working state and non-working state of the check valve are switched by changing the direction of the spring-loaded check valve.

[0097] In step 3, when the expansion valve opening degree is greater than or equal to a preset opening degree threshold such as 100B, the one-way pipe is closed, and the expansion valve throttles independently. That is, when the controller calculates that the expansion valve opening degree is greater than or equal to 100B based on the opening coefficient and system parameters, the refrigeration system enters the "expansion valve throttling independently" mode. At this time, the one-way pipe is closed or in a non-operating state, and only the expansion valve performs throttling control.

[0098] Step 31: Based on the pressure data of the expansion valve front end collected in real time by the pressure sensor, determine whether the pressure of the expansion valve front end is greater than or equal to the preset pressure threshold, such as 3.0 MPa. If yes, proceed to step 32; otherwise, proceed to step 33.

[0099] Step 32: If it is determined that the pressure at the front end of the expansion valve is greater than or equal to the preset pressure threshold, such as 3.0 MPa, then if the outdoor ambient temperature is higher than the preset temperature threshold, such as 35°C, the nonlinear correction algorithm is used to calculate the expansion valve opening correction value △B, and then step 34 is executed.

[0100] The opening correction value △B = a*△P + b*△T (1).

[0101] The calculation result of the expansion valve opening correction value △B is rounded to the nearest integer. The dimensions of both sides of formula (1) are consistent, and only the numerical value is considered during the calculation. △B is the opening correction value, a is the pressure coefficient, △P is the difference between the current pressure of the refrigeration system and the preset pressure; b is the heat load coefficient, which is related to the outdoor ambient temperature; △T is the difference between the outdoor ambient temperature and the preset high load temperature. △P=Pn-P0, Pn is the current pressure of the refrigeration system (i.e., the pressure at the front end of the expansion valve detected from the front end of the expansion valve), P0 is the preset pressure; △T=Tn-T0, Tn is the outdoor ambient temperature, T0 is the preset high load temperature.

[0102] The values ​​of a and b are empirical data and are related to the refrigeration system. The pressure resistance and reliability of the unit vary depending on the application and the cooling capacity range, so the coefficients may be different. Generally, the recommended values ​​for air conditioners are: a range of 10~50; b range of 1~10.

[0103] If it is determined that the pressure at the front end of the expansion valve is greater than or equal to the preset pressure threshold, such as 3.0 MPa, but the outdoor ambient temperature is less than or equal to 35℃, then the heat load coefficient is b=0, that is, the opening correction value △B=a*△P+b*△T=a*△P+0.

[0104] The nonlinear correction algorithm is mainly aimed at the fixed proportional linear control method in the relevant scheme. The control method in the relevant scheme determines whether the expansion valve opens or closes based on the difference between the exhaust temperature and the target exhaust temperature. The nonlinear correction algorithm takes into account the ambient temperature and system pressure, and does not add or subtract in a fixed proportion. Instead, it calculates the correction value based on the coupling of pressure difference and temperature difference, which is more accurate.

[0105] Step 33: If it is determined that the pressure at the front end of the expansion valve is <3.0 MPa, then the opening of the expansion valve will not be corrected regardless of the change in the outdoor ambient temperature, that is, the expansion valve opening correction value △B=0, and then proceed to step 34.

[0106] Step 34: When the expansion valve opening (i.e., the calculated expansion valve opening) is greater than or equal to the preset opening threshold, such as 100B, record the expansion valve opening (i.e., the calculated expansion valve opening) as the calculated expansion valve opening B1, and record the actual operating opening of the expansion valve as the actual operating expansion valve opening B2. The actual operating expansion valve opening B2 = calculated expansion valve opening B1 - expansion valve opening correction value △B, to prevent excessively fast refrigerant flow in the expansion valve from causing a sudden pressure drop and whistling sound. After step 34, return to step 31 to continue judging whether the expansion valve front-end pressure is greater than or equal to the preset pressure threshold, such as 3.0 MPa, based on the real-time feedback of the expansion valve front-end pressure data collected by the pressure sensor. Thus, dynamic adjustment of the expansion valve opening is achieved based on the feedback of the real-time expansion valve front-end pressure data collected by the pressure sensor.

[0107] Assuming P0 = 3 MPa, T0 = 35℃, a = 15, b = 1, then: when the outdoor ambient temperature Tn is 40℃, the pressure Pn detected at the front end of the expansion valve is 3.5 MPa, and the opening degree of the expansion valve (i.e., the calculated opening degree of the expansion valve) is 450B, then △B = 15 * (3.5 - 3) + 1 * (40 - 35) = 13 (B); that is, the actual operating opening degree B2 = 450 - 13 = 437 (B).

[0108] In steps 3 to 34, under high temperature and high pressure conditions, the controller calculates the expansion valve opening correction value △B = a*△P + b*△T using a nonlinear correction algorithm based on the current outdoor ambient temperature and system pressure. The actual operating opening of the expansion valve is B2 = B1 - △B. For example, under high temperature and high pressure conditions, when the pressure detected at the front end of the expansion valve is ≥3.0 MPa and the outdoor ambient temperature is higher than 35℃, the controller calculates the correction value △B using a nonlinear correction algorithm based on the current outdoor ambient temperature and system pressure. The actual operating opening of the expansion valve is B2 = calculated opening B1 - correction value △B, thereby limiting the refrigerant flow and preventing the refrigerant from flowing too fast, which could cause a sudden pressure drop and a whistling sound (Law of conservation of mass: when the internal structure of the valve body remains unchanged, the greater the refrigerant flow, the higher the flow velocity; when the refrigerant flows through the flared opening inside the expansion valve, the flow channel area suddenly contracts and the flow velocity increases sharply, which can easily cause a sudden pressure drop. When the pressure is lower than the saturated vapor pressure of the refrigerant, bubbles will form inside the liquid, thus causing a whistling sound).

[0109] Step 4: If it is determined that the expansion valve opening (i.e., the calculated opening of the expansion valve) is <100B, the check pipe is opened, the expansion valve and the check pipe are connected in parallel for throttling, and then step 41 is executed.

[0110] Step 41: When the expansion valve opening (i.e., the calculated expansion valve opening) is less than the preset opening threshold, such as 100B, record the expansion valve opening (i.e., the calculated expansion valve opening) as the calculated expansion valve opening B3, and record the actual operating opening of the expansion valve as the actual operating expansion valve opening B4. The check valve maintains constant throttling. The actual operating expansion valve opening B4 = calculated expansion valve opening B3 + constant check valve opening ΔB1, improving the control accuracy of the expansion valve under complex operating conditions and avoiding pressure surges and whistling sounds caused by excessive throttling of the expansion valve.

[0111] Assuming the one-way valve has a constant opening ΔB1 = 30B; when the expansion valve's calculated opening B3 = 60B, the actual operating opening B4 = 60 + 30 = 90 (B).

[0112] Among them, the one-way pipe maintains constant throttling: when the fluid passes through the small hole in the one-way pipe, a pressure drop is generated to ensure a constant throttling effect. Under the condition that the total throttling effect of the refrigeration system remains unchanged, it avoids the expansion valve from over-throttling at too low an opening. That is, it avoids the whistling sound caused by excessive throttling, the formation of a narrow flow channel at the valve needle, and the sudden increase in flow velocity when the expansion valve opening is too small, thus improving the stability and reliability of the refrigeration system operation.

[0113] In addition, after the expansion valve actually operates at an opening of B4, the calculated opening of the expansion valve B3 will be continuously updated. The calculated opening of the expansion valve B3 will change, and the actual operating opening of the expansion valve B4 will also change along with the calculated opening of the expansion valve B3.

[0114] When the expansion valve opening calculated by the controller is less than 100B, the refrigeration system switches to the "expansion valve and check pipe parallel throttling" mode. In this mode, the check pipe maintains a constant throttling (e.g., the calculated opening ΔB1 of the check pipe is 30B), and the actual throttling opening B4 of the expansion valve = calculated opening B3 + ΔB1. The overall throttling effect of the refrigeration system remains unchanged, while avoiding excessive throttling of the expansion valve at low openings (when the expansion valve opening is too small, excessive throttling, the formation of a narrow flow channel at the valve needle, and a sudden increase in flow velocity can also cause a whistling sound), thus improving the stability and reliability of the refrigeration system.

[0115] In the solution of this invention, through the above-mentioned control strategy, when the calculated opening degree of the expansion valve is greater than or equal to 100B, the one-way pipe is closed, and the expansion valve is throttled independently. Based on the current outdoor ambient temperature and system pressure, a nonlinear correction algorithm is used to calculate the expansion valve opening correction value △B=a*△P+b*△T, and the actual operating opening degree of the expansion valve is B2=B1-△B. Based on the real-time pressure feedback mechanism of the pressure sensor, the dynamic adjustment of the expansion valve opening degree is realized. The introduction of the nonlinear correction algorithm and opening correction value under high temperature and high pressure conditions improves control accuracy. Based on the calculated opening degree of the expansion valve, the independent throttling mode or the parallel throttling mode with the one-way pipe is dynamically switched. When the calculated opening degree of the expansion valve is less than 100B, the one-way pipe is open, and the expansion valve is throttled in parallel with the one-way pipe. The actual operating opening degree of the expansion valve is B4=calculated opening degree B3+constant opening degree △B1. This achieves refined control of the expansion valve opening degree, improving the adaptability and operational stability of the refrigeration system under different operating conditions and pressures, especially exhibiting good control performance under extreme conditions such as high temperature and high pressure and low opening degree.

[0116] The technical solution of this embodiment involves setting up a parallel throttling structure of an expansion valve and a one-way pipe for the throttling device in a refrigeration system (such as an air conditioner). When the target throttling opening of the expansion valve in the refrigeration system (such as the calculated opening of the expansion valve) is greater than or equal to a preset opening threshold (such as 100B), the one-way pipe is controlled to close for this parallel throttling structure, allowing the expansion valve to throttle independently. The opening of the expansion valve is dynamically adjusted based on the inlet pressure of the expansion valve in the refrigerant flow direction (such as the pressure at the front end of the expansion valve) and the outdoor ambient temperature. When the throttling opening (such as the calculated opening of the expansion valve) is less than the preset opening threshold (such as 100B), the one-way valve is opened for the parallel throttling structure, so that the expansion valve and the one-way pipe are throttled in parallel. Thus, by setting the parallel throttling structure of the expansion valve and the one-way pipe in the throttling device of the refrigeration system, the one-way pipe is opened or closed according to the target opening of the expansion valve, and the opening of the expansion valve is dynamically adjusted according to the outdoor ambient temperature and the pressure at the front end of the expansion valve, so as to avoid the expansion valve opening being too large or too small, which would cause a sudden change in the refrigerant flow rate and cause noise (such as whistling sound), thus improving the user experience.

[0117] According to an embodiment of the present invention, a control device for a refrigeration system corresponding to a control method for a refrigeration system is also provided. See also Figure 3 The diagram shows a structural schematic of an embodiment of the device of the present invention. The control device of the refrigeration system may include: an acquisition unit 102 and a control unit 104.

[0118] The control unit 104 is configured to control the second throttling element to turn on or off according to the target opening degree of the first throttling element; wherein the target opening degree of the first throttling element is pre-calculated based on the opening degree coefficient of the first throttling element and the system parameters of the refrigeration system; after the refrigeration system is turned on, the target opening degree of the first throttling element is determined. The target opening degree of the first throttling element is as follows: Figure 8 The expansion valve opening is calculated as shown. Calculating the expansion valve opening using an opening coefficient and system parameters is a well-known technique in the air conditioning industry. For the specific functions and processing of this control unit 104, please refer to step S110.

[0119] The acquisition unit 102 is configured to acquire the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element when the second throttling element is turned off; wherein, the inlet pressure of the first throttling element is the pressure at the front end of the first throttling element in the refrigerant flow direction of the refrigeration system. The inlet pressure of the first throttling element is, for example... Figure 8The pressure at the front end of the expansion valve is shown. The outdoor ambient temperature of the refrigeration system is acquired, such as by acquiring the outdoor ambient temperature in real time from a temperature sensor; the inlet pressure of the first throttling element is acquired, such as by acquiring the pressure at the front end of the expansion valve in real time from a pressure sensor. The specific functions and processing of this acquisition unit 102 are described in step S120.

[0120] The control unit 104 is further configured to, when controlling the second throttling element to be turned off, adjust the actual operating opening of the first throttling element in conjunction with the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element, so as to maintain the pressure of the refrigeration system within a stable range; of course, when controlling the second throttling element to be turned on, the actual operating opening of the first throttling element is the sum of the target opening of the first throttling element and the opening of the second throttling element, which can also maintain the pressure of the refrigeration system within a stable range. The specific functions and processing of this control unit 104 are further described in step S130.

[0121] In the solution of this invention, the real-time pressure feedback mechanism based on the pressure sensor enables dynamic adjustment of the expansion valve opening, so that the refrigeration system pressure (i.e., the pressure at the front end of the expansion valve) is maintained in a stable range. This effectively avoids the formation of bubbles and whistling sound caused by excessive refrigerant flow rate, reduces noise, and improves user experience.

[0122] Since the processing and functions implemented by the device in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0123] According to an embodiment of the present invention, a refrigeration system and an air conditioner corresponding to a control device for a refrigeration system are also provided. The refrigeration system and air conditioner may include the control device for the refrigeration system described above.

[0124] Since the processing and functions implemented by the refrigeration system and air conditioner in this embodiment are basically the same as those in the embodiments, principles and examples of the aforementioned devices, any details not covered in this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0125] According to an embodiment of the present invention, a computer program product corresponding to a control method for a refrigeration system is also provided, comprising a computer program that, when executed by a processor, implements the steps of the control method for the refrigeration system described above.

[0126] Since the processing and functions implemented by the product in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in the description of this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0127] According to an embodiment of the present invention, a storage medium corresponding to a control method for a refrigeration system is also provided. The storage medium includes a stored program, wherein, when the program is executed, the device where the storage medium is located is controlled to perform the steps of the control method for the refrigeration system described above.

[0128] Since the processing and functions implemented by the storage medium in this embodiment are basically the same as the embodiments, principles and examples of the aforementioned methods, any details not covered in this embodiment can be found in the relevant descriptions in the aforementioned embodiments, and will not be repeated here.

[0129] In summary, it is readily understood by those skilled in the art that, without conflict, the aforementioned advantageous methods can be freely combined and superimposed.

[0130] The above description is merely an embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A control method for a refrigeration system, characterized in that, The refrigeration system has a throttling device; The throttling device includes: a first throttling element and a second throttling element, wherein the opening degree of the first throttling element is adjustable, and the first throttling element and the second throttling element are connected in parallel; the control method of the refrigeration system includes: Based on the target opening degree of the first throttling element, control the second throttling element to be turned on or off; Obtain the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element; With the second throttling element turned off, the actual operating opening of the first throttling element is adjusted based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element.

2. The control method for the refrigeration system according to claim 1, characterized in that, The first throttling element includes: an expansion valve; the second throttling element includes: a one-way pipe; wherein, In the refrigerant flow direction of the refrigeration system, the inlet of the expansion valve is connected to the inlet of the one-way pipe, and the outlet of the expansion valve is connected to the outlet of the one-way pipe.

3. The control method for the refrigeration system according to claim 1 or 2, characterized in that, Controlling the second throttling element to turn on or off according to the target opening degree of the first throttling element includes: Determine whether the target opening degree of the first throttling element is greater than or equal to a preset opening threshold; If it is determined that the target opening degree of the first throttling element is greater than or equal to the preset opening degree threshold, then the second throttling element is controlled to turn off. If it is determined that the target opening degree of the first throttling element is less than the preset opening degree threshold, then the second throttling element is controlled to open.

4. The control method for the refrigeration system according to any one of claims 1 to 3, characterized in that, Based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element, the actual operating opening of the first throttling element is adjusted, including: Determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold; If it is determined that the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold, then the opening correction value of the first throttling element is determined based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element. Based on the opening correction value of the first throttling element, the target opening of the first throttling element is adjusted as the actual operating opening of the first throttling element.

5. The control method for the refrigeration system according to claim 4, characterized in that, in, Based on the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element, the opening correction value of the first throttling element is determined, including: The difference between the outdoor ambient temperature of the refrigeration system and a preset temperature threshold is determined and recorded as the outdoor temperature difference of the refrigeration system; and the difference between the inlet pressure of the first throttling element and a preset pressure threshold is determined and recorded as the inlet pressure difference of the first throttling element. When it is determined that the outdoor ambient temperature of the refrigeration system is greater than the preset temperature threshold, the product of the preset pressure coefficient and the inlet pressure difference of the first throttling element is recorded as the first product value, the product of the preset heat load coefficient and the outdoor temperature difference of the refrigeration system is recorded as the second product value, and the sum of the first product value and the second product value is used as the opening correction value of the first throttling element. When the outdoor ambient temperature of the refrigeration system is determined to be less than or equal to a preset temperature threshold, the product of the preset pressure coefficient and the inlet pressure difference of the first throttling element is recorded as the first product value, which is used as the opening correction value of the first throttling element. And / or, Adjusting the target opening of the first throttling element according to its opening correction value, as the actual operating opening of the first throttling element, includes: The difference between the target opening degree of the first throttling element and the opening degree correction value of the first throttling element is determined as the actual operating opening degree of the first throttling element; The first throttling element is controlled to operate at its actual opening degree, and after a set time, it returns to re-determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold.

6. The control method for the refrigeration system according to any one of claims 1 to 5, characterized in that, In conjunction with the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element, adjusting the actual operating opening of the first throttling element further includes: Determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold; If it is determined that the inlet pressure of the first throttling element is less than the preset pressure threshold, then the target opening of the first throttling element is taken as the actual operating opening of the first throttling element. The first throttling element is controlled to operate at its actual opening degree, and after a set time, it returns to re-determine whether the inlet pressure of the first throttling element is greater than or equal to a preset pressure threshold.

7. A control device for a refrigeration system that uses the control method of any one of claims 1 to 6 to achieve refrigeration system control, characterized in that, include: The control unit is configured to control the second throttling element to be turned on or off according to the target opening degree of the first throttling element; The acquisition unit is configured to acquire the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element; The control unit is further configured to, when controlling the second throttling element to turn off, adjust the actual operating opening of the first throttling element in conjunction with the outdoor ambient temperature of the refrigeration system and the inlet pressure of the first throttling element.

8. A refrigeration system, characterized in that, include: The control device for the refrigeration system as described in claim 7.

9. An air conditioner, characterized in that, include: The control device for the refrigeration system as described in claim 7, or the refrigeration system as described in claim 8.

10. A storage medium, characterized in that, The storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the storage medium to perform the control method of the refrigeration system according to any one of claims 1 to 6.

11. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the control method for the refrigeration system according to any one of claims 1 to 6.

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