A pressure control method and device of an air conditioning system and the air conditioning system

Abstract

This invention discloses a pressure control method, device, and system for an air conditioning system, relating to the field of pressure control. By acquiring the current compressor speed, and the current evaporating and condensing pressures of the compressor, the method determines whether the condensing pressure is greater than a preset maximum condensing pressure corresponding to the current compressor speed. If it is greater, the method increases the speed of the outdoor fan of the air conditioning system. If not, it further determines whether the ratio between the condensing and evaporating pressures is within a preset pressure ratio range. If it is, the air conditioning system pressure is considered normal; otherwise, the method adjusts the speed of the outdoor fan. By determining whether the condensing pressure is too high and whether the ratio between the condensing and evaporating pressures is reasonable, and dynamically controlling the speed of the outdoor fan accordingly, the method can effectively reduce the condensing pressure and the overall power consumption of the air conditioning system under low outdoor temperatures, while ensuring that the ratio between the condensing and evaporating pressures is normal, thereby improving the reliability and energy efficiency ratio of the compressor.

Description

Technical Field

[0001] This invention relates to the field of pressure control, and in particular to a pressure control method, apparatus, and air conditioning system for an air conditioning system. Background Technology

[0002] In a variable frequency air conditioning system, the compressor adjusts its motor speed in real time according to cooling demand to maintain a match between the compressor's output and the actual load. However, in current technology, a corresponding condensing pressure reference value is typically set in advance based on experience to determine different cooling requirements, and the air conditioning system is controlled based on this fixed reference value during actual application. This control method will maintain a relatively high condensing pressure even when the outdoor ambient temperature is low, resulting in relatively high overall power consumption and a low energy efficiency ratio for the air conditioning system.

[0003] Meanwhile, the method of controlling condensing pressure based on a fixed reference value may exceed the compressor's operating curve in certain environments, thereby affecting the compressor's lifespan and the reliability of the air conditioning system. In addition, under the aforementioned conditions of low outdoor ambient temperature and high indoor load, the ratio between the air conditioning system's condensing pressure and evaporating pressure may exceed the compressor's normal pressure ratio range, which also affects the compressor's lifespan and reliability. Summary of the Invention

[0004] The purpose of this invention is to provide a pressure control method, device, and air conditioning system for an air conditioning system. By determining whether the condensing pressure is too high and whether the ratio between the condensing pressure and the evaporating pressure is reasonable, the speed of the outdoor fan is dynamically controlled based on this. This can effectively reduce the condensing pressure and the overall power consumption of the air conditioning system under low outdoor temperatures, while ensuring that the ratio between the condensing pressure and the evaporating pressure is normal, thereby improving the reliability and energy efficiency ratio of the compressor.

[0005] To solve the above-mentioned technical problems, the present invention provides a pressure control method for an air conditioning system, comprising:

[0006] Obtain the current first speed of the compressor;

[0007] Obtain the current evaporation pressure and condensation pressure of the compressor;

[0008] Determine whether the condensing pressure is greater than the preset maximum condensing pressure corresponding to the first rotation speed;

[0009] If the pressure exceeds the preset maximum condensing pressure, the second rotation speed of the outdoor fan in the air conditioning system is increased.

[0010] If it is not greater than the preset maximum condensing pressure, then determine whether the ratio between the condensing pressure and the evaporating pressure is within the preset pressure ratio range corresponding to the first rotation speed;

[0011] If the pressure ratio is within the preset range, the pressure of the air conditioning system is determined to be normal.

[0012] If the pressure ratio exceeds the maximum value of the preset range, the second rotation speed of the air conditioner's outdoor fan is increased.

[0013] If the pressure ratio is less than the minimum value of the preset range, the second speed of the air conditioner's outdoor fan is reduced.

[0014] On the one hand, after obtaining the current evaporation pressure and condensation pressure of the compressor, the method further includes:

[0015] Determine whether the evaporation pressure is within the preset evaporation pressure range corresponding to the first rotation speed;

[0016] If the evaporation pressure is less than the minimum value of the preset evaporation pressure range, the opening degree of the expansion valve in the air conditioning system is increased.

[0017] If the evaporation pressure is greater than the maximum value of the preset evaporation pressure range, the opening degree of the expansion valve is reduced.

[0018] On the one hand, before controlling the increase in the opening degree of the expansion valve in the air conditioning system, the following steps are also included:

[0019] Determine whether the opening degree of the expansion valve is the preset maximum opening degree;

[0020] If it is not the preset maximum opening, then proceed to the step of controlling the opening of the expansion valve in the air conditioning system to increase;

[0021] If the preset maximum opening is reached, then the first speed of the compressor is reduced.

[0022] Before controlling the reduction of the opening degree of the expansion valve, the method further includes:

[0023] Determine whether the opening degree of the expansion valve is the preset minimum opening degree;

[0024] If the minimum opening is not set, then proceed to the step of controlling the opening of the expansion valve to decrease.

[0025] If the preset minimum opening degree is reached, the first speed of the compressor is increased.

[0026] On the one hand, after determining that the pressure of the air conditioning system is normal, it also includes:

[0027] The minimum value of the pressure ratio preset range corresponding to the first rotational speed is multiplied by the value of the evaporation pressure of the compressor to obtain the value of the new condensation pressure.

[0028] The condensing pressure of the compressor is adjusted to the new condensing pressure.

[0029] The actual value of the condensation pressure is adjusted in real time based on the evaporation pressure and the ratio.

[0030] On the one hand, before controlling the second speed increase of the air conditioner's outdoor fan, the method also includes:

[0031] Determine whether the current second speed of the air conditioner's outdoor fan is the first preset maximum speed;

[0032] If it is not the first preset maximum speed, then proceed to the second step of increasing the speed of the air conditioner's outdoor fan;

[0033] If it is the highest speed, then control the first speed of the compressor to decrease;

[0034] Before controlling the second speed reduction of the air conditioner's outdoor fan, the method further includes:

[0035] Determine whether the current second speed of the air conditioner's outdoor fan is the first preset minimum speed;

[0036] If it is not the first preset minimum speed, then proceed to the second step of controlling the speed reduction of the air conditioner's outdoor fan;

[0037] If the speed is at its lowest, then the first speed of the compressor is increased.

[0038] On the one hand, before controlling the first speed reduction of the compressor, it also includes:

[0039] Determine whether the current first speed of the compressor is the second preset minimum speed;

[0040] If not, proceed to the step of controlling the compressor to reduce its first speed;

[0041] If so, and the second speed of the air conditioner's outdoor fan is the first preset maximum speed, then the compressor is controlled to stop.

[0042] Before controlling the first increase in the compressor speed, the following is also included:

[0043] Determine whether the current first speed of the compressor is the second preset maximum speed;

[0044] If not, proceed to the step of increasing the first speed of the compressor;

[0045] If so, and the second speed of the air conditioner's outdoor fan is the first preset minimum speed, then the compressor is controlled to stop.

[0046] On the one hand, while controlling the compressor to stop, it also includes:

[0047] A prompt signal is generated and sent to the prompt module so that the prompt module can issue a prompt.

[0048] On the one hand, before obtaining the compressor's current first speed, it also includes:

[0049] Determine the target speed of the compressor;

[0050] The compressor is controlled to operate at a preset speed;

[0051] After a first preset time period, the compressor is subjected to PI control in order to control the compressor speed to the target speed;

[0052] After a second preset time period, the step of obtaining the current first speed of the compressor begins.

[0053] This application also provides a pressure control device for an air conditioning system, comprising:

[0054] Memory, used to store computer programs;

[0055] A processor is used to execute the computer program to implement the steps of the pressure control method for the air conditioning system as described above.

[0056] This application also provides an air conditioning system, including an air conditioning system body and a pressure control device for the air conditioning system as described above;

[0057] The air conditioning system body is connected to the air conditioning system pressure control device.

[0058] The beneficial effects of this application are that it provides a pressure control method, device, and air conditioning system for an air conditioning system, relating to the field of pressure control. By acquiring the current compressor speed, and acquiring the current evaporating and condensing pressures of the compressor, it determines whether the condensing pressure is greater than the preset maximum condensing pressure corresponding to the current compressor speed. If it is greater, the speed of the outdoor fan of the air conditioning system is increased. If it is not greater, it further determines whether the ratio between the condensing pressure and the evaporating pressure is within a preset pressure ratio range. If it is, the pressure of the air conditioning system is determined to be normal; otherwise, the speed of the outdoor fan is adjusted. By determining whether the condensing pressure is too high and whether the ratio between the condensing pressure and the evaporating pressure is reasonable, and based on this, the speed of the outdoor fan is dynamically controlled, the condensing pressure and power consumption under low outdoor temperatures can be effectively reduced, while ensuring that the ratio between the condensing pressure and the evaporating pressure is normal, thereby improving the reliability and energy efficiency ratio of the compressor. Attached Figure Description

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the prior art and embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0060] Figure 1 A flowchart illustrating a pressure control method for an air conditioning system provided in one embodiment of this application;

[0061] Figure 2 A flowchart illustrating another pressure control method for an air conditioning system provided in an embodiment of this application;

[0062] Figure 3 A graph illustrating the pressure operating range provided in one embodiment of this application;

[0063] Figure 4 This is a schematic diagram of the structure of a pressure control device for an air conditioning system provided in an embodiment of this application. Detailed Implementation

[0064] The core of this invention is to provide a pressure control method, device, and air conditioning system for an air conditioning system. By determining whether the condensing pressure is too high and whether the ratio between the condensing pressure and the evaporating pressure is reasonable, the speed of the outdoor fan is dynamically controlled based on this. This can effectively reduce the condensing pressure and the overall power consumption of the air conditioning system under low outdoor temperatures, while ensuring that the ratio between the condensing pressure and the evaporating pressure is normal, thereby improving the reliability and energy efficiency ratio of the compressor.

[0065] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0066] The commonly used method for controlling condensing pressure in existing technologies is based on adjusting a fixed condensing pressure reference value. This control method has the following problems:

[0067] 1. It fails to consider how changes in ambient temperature affect the overall power consumption and energy efficiency ratio of the air conditioning system. Regardless of whether the outdoor ambient temperature is high or low, the condensing pressure is adjusted based on a fixed baseline value. In some low-temperature outdoor conditions (i.e., when the ambient temperature at the outdoor fan of the air conditioning system is low), this method results in a relatively high condensing pressure for the air conditioning system, leading to relatively high power consumption and thus reducing the annual energy efficiency ratio of the air conditioning system. Simply put, in low-temperature outdoor conditions, the air conditioning system can theoretically meet the user's cooling requirements with a lower condensing pressure and power consumption. However, because current technology controls the condensing pressure according to a fixed baseline value, which is usually set to account for high-temperature outdoor conditions, this fixed baseline value is usually high. Ultimately, this leads to the air conditioning system operating at a relatively higher condensing pressure than theoretically possible in low-temperature outdoor conditions, resulting in higher power consumption than theoretically possible.

[0068] 2. Adjusting the compressor speed based on a fixed target value of condensing pressure may result in the actual value of the condensing pressure exceeding the compressor's operating curve in certain environments, leading to a reduction in compressor lifespan and overall machine reliability.

[0069] 3. When the outdoor ambient temperature is low and the indoor load is high (that is, the condensing pressure is low and the evaporating pressure is high), because the condensing pressure is much higher than the evaporating pressure (usually several times), the pressure ratio between the system's condensing pressure and evaporating pressure will exceed the normal pressure ratio range of the compressor. This will also affect the reliability of the compressor and may even lead to compressor damage.

[0070] To solve the above technical problems, please refer to Figure 1 , Figure 1 A flowchart of a pressure control method for an air conditioning system provided in one embodiment of this application includes:

[0071] S1: Obtain the current first speed of the compressor;

[0072] Each compressor has its own corresponding operating range curve; please refer to [the relevant documentation / reference]. Figure 3 , Figure 3This application provides a pressure operating range curve, which represents the condensing pressure range and evaporating pressure range of the compressor at different speeds. This curve is determined by the compressor manufacturer at the time of manufacture. Therefore, the condensing pressure range and evaporating pressure range corresponding to different speeds can be written into a processor file or a memory connected to the processor. In other words, the operating range curve can be predetermined and stored as a reference for the maximum condensing pressure and evaporating pressure range corresponding to the first speed mentioned later. During normal operation of the air conditioning system and the compressor, the real-time speed of the compressor is acquired, and the reasonable condensing pressure range and evaporating pressure range corresponding to the compressor at this time are determined according to the operating range curve, so as to dynamically adjust the condensing pressure later.

[0073] S2: Obtain the current evaporating and condensing pressures of the compressor;

[0074] Considering that an excessively large pressure ratio between condensing and evaporating pressures can also affect the reliability of the compressor, a point not taken into account in current technology, it is necessary to determine not only the real-time condensing pressure of the compressor but also its real-time evaporating pressure during normal operation of the air conditioning system and the compressor, in order to subsequently determine the pressure ratio between the two.

[0075] S3: Determine whether the condensing pressure is greater than the preset maximum condensing pressure corresponding to the first rotation speed;

[0076] As can be seen from the above, after obtaining the real-time speed of the compressor, the condensing pressure range and evaporating pressure range corresponding to the compressor at the current speed can be determined according to the pre-stored operating range curve. Therefore, after determining the real-time condensing pressure of the compressor, it is compared with the condensing pressure range corresponding to the compressor at the current speed described in the operating range curve to determine whether the real-time condensing pressure exceeds the condensing pressure range corresponding to the compressor at the current speed.

[0077] It should also be noted that in the actual operating conditions of an air conditioning system, the condensing pressure is usually greater than the evaporating pressure. Therefore, the condensing pressure range can be simply set to a pressure range of 0 to X, where X is the maximum value of the evaporating pressure range corresponding to the current compressor speed. When determining whether the real-time condensing pressure exceeds the condensing pressure range corresponding to the current compressor speed, it is only necessary to determine whether the real-time condensing pressure is greater than X.

[0078] S4: If the pressure exceeds the preset maximum condensing pressure, the second speed of the outdoor fan in the air conditioning system will be increased.

[0079] When the real-time condensing pressure of the compressor is too high, in order to reduce the impact on the compressor caused by controlling the compressor, the processor will prioritize increasing the speed of the outdoor fan of the air conditioning system, thereby reducing the impact on the compressor while lowering the condensing pressure.

[0080] S5: If it is not greater than the preset maximum condensing pressure, then determine whether the ratio between the condensing pressure and the evaporating pressure is within the preset pressure ratio range corresponding to the first rotation speed;

[0081] When the compressor's real-time condensing pressure does not exceed its maximum value, from the perspective of current technology, the pressure of the entire air conditioning system can be considered normal. However, this doesn't consider that an excessively high ratio between condensing and evaporating pressure can also affect the compressor. Therefore, when the compressor's real-time condensing pressure does not exceed its maximum value, the next step is to calculate the ratio of the real-time condensing pressure to the real-time evaporating pressure. This ratio should be checked to see if it falls within the pressure ratio range described in the operating range curve corresponding to the compressor's current speed. If it falls within this range, the pressure of the entire air conditioning system can be considered normal; otherwise, the condensing pressure is still too high, and the outdoor fan speed needs to be further increased.

[0082] S6: If the pressure ratio is within the preset range, the air conditioning system pressure is considered normal.

[0083] S7: If the pressure ratio exceeds the maximum value of the preset range, the second speed of the outdoor fan of the air conditioner will be increased.

[0084] S8: If the pressure ratio is less than the minimum value of the preset range, the second speed of the outdoor fan of the air conditioner will be reduced.

[0085] For a specific example, please refer to... Figure 2 , Figure 2 The flowchart illustrates another pressure control method for an air conditioning system provided in an embodiment of this application. It assumes that the compressor speed range has five zones: 12–24 rpm, 24–45 rpm, 45–70 rpm, 70–90 rpm, and 90–120 rpm. Figure 3 The information can be used to calculate the high and low pressure operating range and pressure ratio operating range of each frequency band, as shown in Table 1 below. Pe represents the evaporation pressure, Pc represents the condensation pressure, F represents the current speed of the compressor, and ε represents the ratio of the two pressures, namely Pc / Pe.

[0086] Table 1: Operating range and pressure ratio range of the compressor's condensing and evaporating pressures

[0087]

[0088]

[0089] The parameters in Table 1 can all be obtained when the compressor leaves the factory. To verify the range of the two pressures of the compressor again, they can be calculated again based on the real-time speed.

[0090] By dynamically adjusting the pressure, in some standard typical year-round energy efficiency tests, when the outdoor ambient temperature is low, the existing technology of controlling the pressure according to a fixed value will not adjust the pressure to save energy when the entire air conditioning system is running in steady state. The condensing pressure will be adjusted to a fixed value, which is relatively high for such low outdoor temperatures, so the energy consumption of the entire air conditioning system is also relatively high. However, after the air conditioning system stabilizes, this application further adjusts the condensing pressure so that the ratio of the two pressures approaches the minimum ratio at the current compressor speed, thereby reducing system power and improving the energy efficiency ratio. In other words, this application reduces condensing pressure and energy consumption compared to the existing technology. Table 2 below shows the actual test data of a certain model, demonstrating the difference between this application and the existing technology.

[0091] Table 2 Comparison data of actual tests for a certain model

[0092] compressor frequency rps 78 80 Actual air volume <![CDATA[m 3 / h]]> 3184.2 3188.5 Air-side cooling capacity W 12685.0 12367.6 Energy efficiency ratio W / W 5.50 4.71 Outdoor air intake dry bulb ℃ 5.01 5.09 Indoor air intake dry bulb ℃ 24.02 24.01 Indoor air intake wet bulb ℃ 17.06 17.06 Indoor air dry bulb ℃ 14.07 14.07 Indoor air outlet wet bulb ℃ 12.76 12.87 Test machine power W 2307.5 2623.7 Evaporation pressure Bar 10.06 10.29 Condensation pressure Bar 20.21 22.63 System pressure ratio Bar / Bar 2.01 2.20

[0093] As can be seen from Table 2 above, while ensuring that the temperature is basically the same as that of the prior art, the parameters such as condensing pressure, system pressure ratio and overall power of air conditioning are all lower than those of the prior art, and the energy efficiency ratio is higher than that of the prior art.

[0094] In summary, by acquiring the current compressor speed, evaporating pressure, and condensing pressure, the system determines whether the condensing pressure exceeds the preset maximum condensing pressure corresponding to the specified speed. If it does, the speed of the outdoor fan in the air conditioning system is increased. If not, the system further checks whether the ratio of condensing pressure to evaporating pressure is within the preset pressure ratio range. If it is, the air conditioning system pressure is considered normal; otherwise, the speed of the outdoor fan is adjusted. By determining whether the condensing pressure is too high and whether the ratio of condensing pressure to evaporating pressure is reasonable, and based on this, the outdoor fan speed is dynamically controlled. This effectively reduces the condensing pressure and the overall power consumption of the air conditioning system under low outdoor temperatures, while ensuring that the ratio of condensing pressure to evaporating pressure is normal. This improves the reliability of the compressor and the energy efficiency ratio of the air conditioning system in low outdoor environments.

[0095] Based on the above embodiments:

[0096] In some embodiments, after obtaining the current evaporating pressure and condensing pressure of the compressor, the method further includes:

[0097] Determine whether the evaporation pressure is within the preset evaporation pressure range corresponding to the first rotation speed;

[0098] If the evaporation pressure is less than the minimum value of the preset evaporation pressure range, the opening degree of the expansion valve in the air conditioning system will be increased.

[0099] If the evaporation pressure is greater than the maximum value of the preset evaporation pressure range, the opening degree of the expansion valve will be reduced.

[0100] To further protect the compressor, this application considers that the compressor's evaporation pressure may change during actual operation due to variations in indoor temperature or load (i.e., at the air conditioner unit, whether it's a cabinet or wall-mounted unit). For example, the evaporation pressure increases when the indoor load rises. Therefore, when the evaporation pressure changes, because the compressor requires the ratio between condensing and evaporating pressures to remain within a reasonable range for normal operation, and the evaporation pressure itself must also remain within a reasonable range, changes in evaporation pressure will affect not only the condensing pressure but also the compressor itself. Therefore, while checking whether the condensing pressure is greater than the maximum condensing pressure corresponding to the compressor's current speed, it is also necessary to check whether the evaporation pressure is within the range corresponding to the compressor's current speed. If it is, the evaporation pressure is normal; if not, the evaporation pressure is adjusted to meet the preset range of evaporation pressure and pressure ratio. The specific method for adjusting the evaporation pressure is mainly achieved by adjusting the electronic expansion valve in the air conditioning system. The processor adjusts the evaporation pressure by adjusting the opening of the electronic expansion valve, ensuring that the compressor's suction superheat is reasonable. The larger the opening of the electronic expansion valve, the higher the evaporation pressure; conversely, the smaller the opening of the electronic expansion valve, the lower the evaporation pressure. Based on this, the compressor can be further protected.

[0101] In some embodiments, before increasing the opening of the expansion valve in the air conditioning system, the method further includes:

[0102] Determine whether the opening degree of the expansion valve is the preset maximum opening degree;

[0103] If it is not the preset maximum opening, then proceed to the step of increasing the opening of the expansion valve in the air conditioning system;

[0104] If the maximum opening is preset, the first speed of the compressor will be reduced.

[0105] Before controlling the reduction of the expansion valve opening, the following steps are also included:

[0106] Determine whether the opening degree of the expansion valve is the preset minimum opening degree;

[0107] If it is not the preset minimum opening, then proceed to the step of controlling the opening of the expansion valve to decrease;

[0108] If the minimum opening is preset, the compressor's initial speed will increase.

[0109] To further regulate the evaporation pressure, this application considers the limitations of the expansion valve's control capability. If the processor controls the expansion valve's opening to exceed its preset maximum opening, the evaporation pressure cannot be increased further via the electronic expansion valve. Similarly, when the expansion valve's opening is less than the preset minimum opening, the evaporation pressure cannot be decreased via the electronic expansion valve. Therefore, when the compressor's real-time evaporation pressure is outside the evaporation pressure range corresponding to the compressor's current speed, before adjusting the expansion valve, it is necessary to first determine whether the expansion valve has reached its limit (for example, before increasing the expansion valve opening, first determine whether the expansion valve is already at its maximum opening). If it has not reached its limit, the expansion valve can continue to be adjusted. If it has reached its limit and the evaporation pressure is still outside the range, the evaporation pressure needs to be reduced by adjusting the compressor's speed; the higher the compressor speed, the lower the evaporation pressure. Based on this, the evaporation pressure is further regulated.

[0110] In some embodiments, after determining that the pressure of the air conditioning system is normal, the method further includes:

[0111] The minimum value of the pressure ratio preset range corresponding to the first speed is multiplied by the value of the compressor's evaporation pressure to obtain the value of the new condensation pressure.

[0112] Adjust the compressor's condensing pressure to the new condensing pressure;

[0113] The actual value of the condensing pressure is adjusted in real time based on the evaporating pressure and the ratio.

[0114] To save energy and improve the energy efficiency ratio of the air conditioning system, this application proposes that, after confirming that the overall pressure of the air conditioning system is normal, the condensing pressure can be further reduced to decrease the overall power of the air conditioning system, thereby achieving the goals of energy saving and improving the energy efficiency ratio. For details, please refer to... Figure 2 , Figure 2 This is a flowchart illustrating another pressure control method for an air conditioning system provided in an embodiment of this application. The minimum pressure ratio within the range corresponding to the current compressor speed is taken as the target ratio for the air conditioning system. Assuming the target ratio is ε and the current evaporation pressure is Pe, the condensing pressure Pc is adjusted based on the formula Pc = Pe * ε, so that the ratio between the condensing pressure and the evaporation pressure satisfies the minimum value ε within the current pressure ratio range. Based on this, energy savings and an improved energy efficiency ratio of the air conditioning system can be achieved.

[0115] In some embodiments, prior to controlling the second speed increase of the air conditioner's outdoor fan, the method further includes:

[0116] Determine whether the current second speed of the air conditioner's outdoor fan is the first preset maximum speed;

[0117] If it is not the first preset maximum speed, then proceed to the second step of increasing the speed of the air conditioner's outdoor fan;

[0118] If it is the highest speed, then the first speed of the compressor is reduced;

[0119] Before controlling the second speed reduction of the air conditioner's outdoor fan, the following is also included:

[0120] Determine whether the current second speed of the air conditioner's outdoor fan is the first preset minimum speed;

[0121] If it is not the first preset minimum speed, then proceed to the second step of controlling the outdoor fan speed of the air conditioner to decrease;

[0122] If it is the lowest speed, then the first speed of the compressor is increased.

[0123] To further adjust the condensing pressure, as can be seen from the above embodiments, not only does the expansion valve have an adjustment limit, but the outdoor fan also has an adjustment upper limit. When the real-time condensing pressure of the compressor is greater than the maximum condensing pressure corresponding to the current compressor speed, before adjusting the air conditioner's outdoor fan, it is necessary to first determine whether the outdoor fan speed is already at its maximum. If it has not reached its maximum, the outdoor fan speed can be increased further; if it has reached its maximum and the condensing pressure is still outside the range, the condensing pressure needs to be reduced by adjusting the compressor speed. The lower the compressor speed, the lower the condensing pressure. Based on this, the condensing pressure can be further adjusted.

[0124] In some embodiments, prior to controlling the first reduction in compressor speed, the method further includes:

[0125] Determine whether the compressor's current first speed is the second preset minimum speed;

[0126] If not, proceed to the first step of reducing the compressor speed;

[0127] If so, and the second speed of the air conditioner's outdoor fan is the first preset maximum speed, then the compressor will be stopped.

[0128] Before controlling the initial increase in compressor speed, the following steps are also included:

[0129] Determine whether the compressor's current first speed is the second preset maximum speed;

[0130] If not, proceed to the step of increasing the first speed of the compressor;

[0131] If so, and the second speed of the air conditioner's outdoor fan is the first preset minimum speed, then the compressor will be stopped.

[0132] To protect the compressor, in this application, in conjunction with the above embodiments, if the outdoor fan has reached its maximum speed and the compressor has reached its minimum speed, and the condensing pressure is still greater than the maximum condensing pressure corresponding to the compressor's current speed, an abnormal operating pressure report for the air conditioning system will be directly issued, and the compressor will be shut down and exit the cooling state to avoid damage to the compressor and air conditioning system caused by excessively high condensing pressure. Based on this, the compressor can be protected.

[0133] In some embodiments, the method of controlling the compressor to stop also includes:

[0134] A prompt signal is generated and sent to the prompt module so that the prompt module can issue a prompt.

[0135] To promptly alert staff, this application includes a notification module that will issue a notification when the compressor stops due to pressure issues. This notification module can be an auditory notification module (such as a speaker or buzzer) or a visual notification module (such as an LED or display screen) to promptly inform staff that the compressor has stopped.

[0136] In some embodiments, before obtaining the current first speed of the compressor, the method further includes:

[0137] Determine the target speed of the compressor;

[0138] Control the compressor to operate at a preset speed;

[0139] After the first preset time period, the compressor is controlled by PI control in order to control the compressor speed to the target speed;

[0140] After a second preset time period, the step of obtaining the current first speed of the compressor begins.

[0141] To ensure stable compressor control, this application addresses the issue that the compressor's speed is unstable at startup, meaning both condensing and evaporating pressures are unstable. Controlling the compressor at this initial stage would not yield optimal results. Therefore, upon startup, the compressor operates at its default speed for a first preset time. After this time, PI (proportional integral) control is applied to match the user's cooling requirements. After a second preset time, if the compressor speed and frequency remain relatively constant, it is considered to have stabilized. At this point, the real-time compressor speed is acquired to adjust the condensing and evaporating pressures. This approach allows for stable compressor control.

[0142] Please refer to Figure 4 , Figure 4 A schematic diagram of the result of a pressure control device for an air conditioning system provided in an embodiment of this application includes:

[0143] Memory 21 is used to store computer programs;

[0144] The processor 22 is used to execute computer programs to implement the steps of the pressure control method for the air conditioning system described above.

[0145] For a detailed description of the pressure control device for an air conditioning system provided in this application, please refer to the embodiments of the pressure control method for the air conditioning system described above. This application does not limit the scope of comparison.

[0146] This application also provides an air conditioning system, including an air conditioning system body and a pressure control device for the air conditioning system as described above;

[0147] The air conditioning system body is connected to the air conditioning system pressure control device.

[0148] For a detailed description of the air conditioning system provided in this application, please refer to the embodiments of the pressure control method of the air conditioning system described above. This application does not limit the scope of comparison.

[0149] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0150] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0151] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A pressure control method of an air conditioning system, characterized by, include: Determine the target speed of the compressor; The compressor is controlled to operate at a preset speed; After a first preset time period, the compressor is subjected to PI control in order to control the compressor speed to the target speed; After a second preset time period, the current first speed of the compressor is obtained; Obtain the current evaporation pressure and condensation pressure of the compressor; Determine whether the condensing pressure is greater than the preset maximum condensing pressure corresponding to the first rotation speed; If the pressure exceeds the preset maximum condensing pressure, the second rotation speed of the outdoor fan in the air conditioning system is increased. If it is not greater than the preset maximum condensing pressure, then determine whether the ratio between the condensing pressure and the evaporating pressure is within the preset pressure ratio range corresponding to the first rotation speed; If the pressure ratio is within the preset range, the pressure of the air conditioning system is determined to be normal. If the pressure ratio exceeds the maximum value of the preset range, the second rotation speed of the air conditioner's outdoor fan is increased. If the pressure ratio is less than the minimum value of the preset range, the second speed of the air conditioner's outdoor fan is reduced. After determining that the air conditioning system pressure is normal, the following steps are also included: Based on the first rotational speed, and based on the correspondence between a preset rotational speed range and a preset pressure ratio range, the minimum value of the preset pressure ratio range corresponding to the rotational speed range to which the first rotational speed belongs is determined; the minimum value of the preset pressure ratio range corresponding to at least one rotational speed range is a fixed value, and the minimum value of the preset pressure ratio range corresponding to at least another rotational speed range is a function of the first rotational speed; The minimum value of the pressure ratio preset range corresponding to the first rotational speed is multiplied by the value of the evaporation pressure of the compressor to obtain the value of the new condensation pressure. The condensing pressure of the compressor is adjusted to the new condensing pressure. The actual value of the condensation pressure is adjusted in real time based on the evaporation pressure and the ratio.

2. The pressure control method for an air conditioning system as described in claim 1, characterized in that, After obtaining the current evaporating pressure and condensing pressure of the compressor, the process further includes: Determine whether the evaporation pressure is within the preset evaporation pressure range corresponding to the first rotation speed; If the evaporation pressure is less than the minimum value of the preset evaporation pressure range, the opening degree of the expansion valve in the air conditioning system is increased. If the evaporation pressure is greater than the maximum value of the preset evaporation pressure range, the opening degree of the expansion valve is reduced.

3. The pressure control method for an air conditioning system as described in claim 2, characterized in that, Before controlling the increase in the opening degree of the expansion valve in the air conditioning system, the method further includes: Determine whether the opening degree of the expansion valve is the preset maximum opening degree; If it is not the preset maximum opening, then proceed to the step of controlling the opening of the expansion valve in the air conditioning system to increase; If the preset maximum opening is reached, then the first speed of the compressor is reduced. Before controlling the reduction of the opening degree of the expansion valve, the method further includes: Determine whether the opening degree of the expansion valve is the preset minimum opening degree; If the minimum opening is not set, then proceed to the step of controlling the opening of the expansion valve to decrease. If the preset minimum opening degree is reached, the first speed of the compressor is increased.

4. The pressure control method for an air conditioning system as described in claim 1, characterized in that, Before controlling the second speed increase of the air conditioner's outdoor fan, the method further includes: Determine whether the current second speed of the air conditioner's outdoor fan is the first preset maximum speed; If it is not the first preset maximum speed, then proceed to the second step of increasing the speed of the air conditioner's outdoor fan; If it is the highest speed, then control the first speed of the compressor to decrease; Before controlling the second speed reduction of the air conditioner's outdoor fan, the method further includes: Determine whether the current second speed of the air conditioner's outdoor fan is the first preset minimum speed; If it is not the first preset minimum speed, then proceed to the second step of controlling the speed reduction of the air conditioner's outdoor fan; If the speed is at its lowest, then the first speed of the compressor is increased.

5. The pressure control method for an air conditioning system as described in claim 4, characterized in that, Before controlling the first speed reduction of the compressor, the following is also included: Determine whether the current first speed of the compressor is the second preset minimum speed; If not, proceed to the step of controlling the compressor to reduce its first speed; If so, and the second speed of the air conditioner's outdoor fan is the first preset maximum speed, then the compressor is controlled to stop. Before controlling the first increase in the compressor speed, the following is also included: Determine whether the current first speed of the compressor is the second preset maximum speed; If not, proceed to the step of increasing the first speed of the compressor; If so, and the second speed of the air conditioner's outdoor fan is the first preset minimum speed, then the compressor is controlled to stop.

6. The pressure control method for an air conditioning system as described in claim 5, characterized in that, In addition to controlling the compressor to stop, it also includes: A prompt signal is generated and sent to the prompt module so that the prompt module can issue a prompt.

7. A pressure control device for an air conditioning system, characterized in that, include: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the steps of the pressure control method for the air conditioning system as described in any one of claims 1 to 6.

8. An air conditioning system, characterized in that, It includes the air conditioning system body, and also includes the pressure control device of the air conditioning system as described in claim 7; The air conditioning system body is connected to the air conditioning system pressure control device.

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