Compressor control method, air conditioning system and computer-readable storage medium

Abstract

The present invention provides a compressor control method, an air conditioning system and a computer-readable storage medium. The method includes the following steps: S1: After the compressor is started, determine whether the air conditioning system is in a refrigeration mode; S2: If it is in the refrigeration mode, collect the actual pressure of the air conditioning system in real time, and start timing when the actual pressure is greater than the specified pressure threshold; S3: Collect the actual operating frequency Fn of the compressor in real time, and when the actual operating frequency Fn is not less than the first frequency threshold, obtain the total operating duration of the actual operating frequency Fn in different frequency ranges; S4: Calculate the virtual oil return duration according to the operating duration of the compressor in different frequency ranges; S5: Determine whether the virtual oil return duration T is not less than the specified duration threshold; if the virtual oil return duration T is not less than the specified duration threshold, then control the air conditioning system to execute the high oil drainage rate oil return correction control logic. The present invention improves the accuracy of calculating the virtual oil return duration and improves the reliability of the compressor operation.

Description

Technical Field

[0001] The present invention relates to the field of air conditioners, and specifically to a compressor control method for an air conditioning system, an air conditioning system, and a computer-readable storage medium. Background Art

[0002] The existing oil return control logic adopted by multi-connected air conditioner units is as follows: After the compressor accumulatively runs for a set time, oil return control is executed. When the system pressure is high and the compressor runs at a high frequency, the oil discharge rate of the compressor will become very high, and the oil return amount is insufficient. At this time, the oil discharge amount is greater than the oil return amount, and the compressor is prone to running with insufficient oil and even burning out. The existing oil return control for multi-connected units lacks effective oil return correction control for the high-pressure and high-frequency operation of the compressor. Summary of the Invention

[0003] In view of the above problems, the present invention provides a compressor control method for an air conditioning system, an air conditioning system, and a computer-readable storage medium. When the compressor runs at high pressure and high frequency, the operating frequency is divided into intervals, and the virtual oil return duration is calculated according to the operating duration in different frequency ranges, so as to improve the calculation accuracy of the virtual oil return duration. According to the comparison result between the virtual oil return duration and the specified duration threshold, the compressor is controlled to perform oil return operation, thereby improving the reliability of the compressor operation.

[0004] The present invention provides a compressor control method for an air conditioning system. The air conditioning system includes a timer. The compressor control method includes the following steps:

[0005] S1: After the compressor starts, determine whether the air conditioning system is in the cooling mode;

[0006] S2: If the operating mode is the cooling mode, collect the actual pressure of the air conditioning system in real time, and when the actual pressure is greater than the specified pressure threshold, control the timer to start timing;

[0007] S3: Collect the actual operating frequency Fn of the compressor in real time, and when the actual operating frequency Fn is not less than the first frequency threshold, obtain the total operating duration of the actual operating frequency Fn in different frequency ranges;

[0008] S4: Calculate the virtual oil return duration according to the operating duration of the compressor in different frequency ranges;

[0009] S5: Determine whether the virtual oil return duration T is not less than the specified duration threshold; if the virtual oil return duration T is not less than the specified duration threshold, control the air conditioning system to execute the high oil discharge rate oil return correction control logic.

[0010] When the compressor operates at high pressure and high frequency, the present invention divides the operating frequency into intervals, calculates the virtual oil return duration according to the operating duration in different frequency ranges, and enters the high oil discharge rate oil return correction control logic when the virtual oil return duration is greater than the specified duration threshold, and the compressor performs oil return operation, thereby improving the reliability of the compressor operation.

[0011] In an alternative technical solution of the present invention, before step S1, it further includes: presetting a first frequency threshold C, a second frequency threshold B, and a third frequency threshold A, and the first frequency threshold C, the second frequency threshold B, and the third frequency threshold A increase in sequence.

[0012] According to this technical solution, by presetting the first frequency threshold, the second frequency threshold, and the third frequency threshold, the high-frequency operating frequency of the compressor is divided into multiple intervals, the program design is simple, which is beneficial to reducing the complexity of the air-conditioning system and improving its operating efficiency.

[0013] In an alternative technical solution of the present invention, "obtaining the total operating duration of the actual operating frequency Fn in different frequency ranges" includes:

[0014] S31: Determine whether the actual operating frequency Fn is in the first frequency range; if the actual operating frequency Fn is in the first frequency range, then execute S32; if the judgment result is negative, return to the previous step;

[0015] S32: Determine whether the operating frequency Fn is in the second frequency range; if the actual operating frequency Fn is in the second frequency range, then execute S33, and at the same time the timer marks the total operating duration as T1; if not, return to S31;

[0016] S33: Determine whether the actual operating frequency Fn is in the third frequency range; if the actual operating frequency Fn is in the third frequency range, then execute S34, and at the same time the timer marks the total operating duration as T2; if not, return to S32;

[0017] S34: At the same time, the timer marks the total operating duration T3 in real time, and execute S4; wherein, the first frequency range is C ≤ Fn < B, the second frequency range is B ≤ Fn ≤ A, and the third frequency range is Fn ≥ A.

[0018] According to this technical solution, T1 is the running duration of the compressor in the first frequency range, T2 - T1 is the running duration of the compressor in the second frequency range, and T3 - T2 is the running duration of the compressor in the third frequency range. By using a timer to mark the time when the compressor enters the next frequency range, the running duration of the compressor in the previous frequency range can be obtained. The method is simple and easy to operate, reducing the design difficulty of the system. By marking T3 in real time, the virtual oil return duration can be dynamically monitored, and when the virtual oil return duration ≥ the specified duration threshold, the high oil discharge rate oil return correction logic can be executed in a timely manner, improving the reliability of the compressor operation.

[0019] In an alternative technical solution of the present invention, the virtual oil return duration T = T1*c + (T2 - T1)*b + (T3 - T2)*a, where a, b, and c are constants.

[0020] According to this technical solution, by simulating and calculating the virtual oil return duration in combination with the running durations of the compressor in different high-frequency ranges, the accuracy of calculating the virtual oil return duration is improved, and the accuracy of the compressor executing the high oil discharge rate oil return correction control logic is enhanced.

[0021] In an alternative technical solution of the present invention, it also includes controlling the timer to be cleared when the actual running frequency Fn is less than the first frequency threshold.

[0022] According to this technical solution, when the actual running frequency Fn is less than the first frequency threshold, no timing is performed, that is, there is no need to perform the high oil discharge rate oil return correction control logic, which can avoid frequently executing the high oil discharge rate oil return correction control logic and affecting the normal operation of the air-conditioning system.

[0023] In an alternative technical solution of the present invention, the high oil discharge rate oil return correction control logic is configured to: control the compressor to reduce its frequency to the target oil return frequency Fs and run for a duration of T / 20, and then run according to the preset target frequency.

[0024] According to this technical solution, when the compressor operates at high pressure and high frequency, reducing the running frequency can reduce the oil discharge rate of the compressor and increase the oil return rate. Running for a duration of T / 20 can take into account both the oil return effect of the compressor and the normal operation of the system, preventing the oil return time from being too long and affecting the normal operation of the air-conditioning system. The oil return duration T / 20 varies with the calculated virtual oil return duration, improving the accuracy of the high oil discharge oil return correction control of the compressor and enhancing the reliability of the compressor operation.

[0025] In an alternative technical solution of the present invention, it also includes returning to S1 when the virtual oil return duration T is less than the specified duration threshold.

[0026] According to this technical solution, when the virtual oil return duration is less than the specified duration threshold, returning to S1 means not executing the high oil discharge rate oil return correction control logic, which can avoid frequently running the high oil discharge rate oil return correction control logic and affecting the operation of the air-conditioning system.

[0027] In an alternative technical solution of the present invention, the first frequency range is 110 ≤ Fn < 120 Hz, the second frequency range is 120 ≤ Fn < 130 Hz, and the third frequency range is Fn ≥ 130 Hz.

[0028] On the other hand, the present invention provides an air-conditioning system that executes the compressor control method of the above-mentioned air-conditioning system.

[0029] On the other hand, the present invention provides a computer-readable storage medium storing a computer program, and the computer program executes the compressor control method of the above-mentioned air-conditioning system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic flowchart of the compressor control method of the air-conditioning system in the embodiment of the present invention.

[0031] Figure 2 It is a specific flowchart of step S3 in the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0033] As Figure 1 shown, the present invention provides a compressor control method for an air-conditioning system. The air-conditioning system includes a timer, and the compressor control method includes the following steps:

[0034] S1: After the compressor is started, determine whether the air-conditioning system is in the cooling mode;

[0035] S2: If the operating mode is the cooling mode, collect the actual pressure Pc of the air-conditioning system in real time, and when the actual pressure Pc is greater than the specified pressure threshold Ps, control the timer to start timing;

[0036] S3: Collect the actual operating frequency Fn of the compressor in real time, and when the actual operating frequency Fn is not less than the first frequency threshold, obtain the total operating duration of the actual operating frequency Fn in different frequency ranges;

[0037] S4: Calculate the virtual oil return duration according to the operating duration of the compressor in different frequency ranges;

[0038] S5: Determine whether the virtual oil return duration T is not less than the specified duration threshold Ts; if the virtual oil return duration T is not less than the specified duration threshold Ts, then control the air conditioning system to execute the high oil drainage rate oil return correction control logic.

[0039] In the present invention, when the compressor operates at high pressure and high frequency, the operating frequency is divided into intervals, and the virtual oil return duration is calculated according to the operating duration in different frequency ranges, improving the accuracy of the virtual oil return duration calculation. When the virtual oil return duration is greater than the specified duration threshold, enter the high oil drainage rate oil return correction control logic, and the compressor performs oil return operation, improving the reliability of the compressor operation. At the same time, it avoids frequent oil return of the compressor and improves the stability of the air conditioning system operation.

[0040] In a preferred embodiment of the present invention, before step S1, it further includes: presetting a first frequency threshold C, a second frequency threshold B, and a third frequency threshold A, and the first frequency threshold C, the second frequency threshold B, and the third frequency threshold A increase in sequence.

[0041] In an embodiment of the present invention, by presetting the first frequency threshold C, the second frequency threshold B, and the third frequency threshold A, the high-frequency operating frequency of the compressor is divided into multiple intervals, the program design is simple, which is beneficial to reducing the complexity of the air conditioning system and improving its operating efficiency. In some other embodiments, two, four, five, etc. multiple frequency thresholds can also be preset, and the multiple frequency thresholds correspond to multiple frequency ranges, improving the accuracy of the virtual oil return duration calculation. In the embodiment of the present invention, preferably 3 frequency thresholds are used, which can take into account the accuracy of the virtual oil return duration calculation and reduce the complexity of the system, reduce the amount of operation, and improve the system operating efficiency.

[0042] As Figure 2 shown, in a preferred embodiment of the present invention, "obtaining the operating durations of the actual operating frequency Fn in different frequency ranges respectively" includes:

[0043] S31: Determine whether the actual operating frequency Fn is in the first frequency range; if the actual operating frequency Fn is in the first frequency range, then execute S32; if the judgment result is negative, then return to the previous step;

[0044] S32: Determine whether the operating frequency Fn is in the second frequency range; if the actual operating frequency Fn is in the second frequency range, then execute S33, and at the same time the timer marks the total operating duration as T1; if not, then return to S31;

[0045] S33: Determine whether the actual operating frequency Fn is in the third frequency range; if the actual operating frequency Fn is in the third frequency range, then execute S34, and at the same time the timer marks the total operating duration as T2; if not, then return to S32;

[0046] S34: Meanwhile, the timer marks the total running duration T3 in real time and executes S4; wherein, the first frequency range is C ≤ Fn < B, the second frequency range is B ≤ Fn ≤ A, and the third frequency range is Fn ≥ A.

[0047] In the above manner, T1 is the running duration of the compressor in the first frequency range, T2 is the total running duration of the compressor in the first and second frequency ranges, T2 - T1 is the running duration of the compressor in the second frequency range, T3 is the total running duration of the compressor in the first, second, and third frequency ranges, and T3 - T2 is the running duration of the compressor in the third frequency range. By counting the total running duration of the compressor in the current frequency range and the previous frequency range with a timer and marking the time when the compressor enters the next frequency range, the running duration of the compressor in the current frequency range can be obtained. The method is simple and easy to operate, reducing the design difficulty of the system; by marking the total running duration T3 in real time and calculating the virtual oil return duration T, the virtual oil return duration T can be dynamically monitored, and when the virtual oil return duration T ≥ the specified duration threshold Ts, the high oil discharge rate oil return correction logic can be executed in a timely manner, improving the reliability of the compressor operation.

[0048] In the preferred embodiment of the present invention, the virtual oil return duration T = T1 * c + (T2 - T1) * b + (T3 - T2) * a, where a, b, and c are constants. By combining the running durations in different high-frequency ranges of the compressor to simulate and calculate the virtual oil return duration, the accuracy of the virtual oil return duration calculation is improved, and the accuracy of the compressor executing the high oil discharge rate oil return correction control logic is improved. The specific values of a, b, and c can be determined by conducting multiple experiments on the air-conditioning system in the cooling mode.

[0049] In the preferred embodiment of the present invention, it further includes controlling the timer to be cleared when the actual operating frequency Fn is less than the first frequency threshold.

[0050] In the above manner, when the actual operating frequency Fn is less than the first frequency threshold, no timing is performed, that is, there is no need to execute the high oil discharge rate oil return correction control logic, which can avoid frequently executing the high oil discharge rate oil return correction control logic and affecting the normal operation of the air-conditioning system.

[0051] In a preferred embodiment of the present invention, the high oil discharge rate oil return correction control logic is configured to: control the compressor to reduce its frequency to the target oil return frequency Fs and operate for a duration of T / 20, and then operate according to a preset target frequency. The preset target frequency is the set frequency of the air-conditioning system in the cooling mode, i.e., the target oil return frequency. In this way, when the compressor operates at high pressure and high frequency, reducing the operating frequency can reduce the oil discharge rate of the compressor and increase the oil return rate. Operating for a duration of T / 20 can balance the oil return effect of the compressor and the normal operation of the system, preventing the oil return time from being too long and affecting the normal operation of the air-conditioning system. The oil return duration T / 20 varies with the calculated virtual oil return duration, improving the accuracy of the high oil discharge rate oil return correction control logic and enhancing the reliability of the compressor operation.

[0052] In a preferred embodiment of the present invention, it further includes returning to S1 when the virtual oil return duration T is less than the specified duration threshold Ts. That is, not executing the high oil discharge rate oil return correction control logic can avoid frequently operating the high oil discharge rate oil return correction control logic and affecting the operation of the air-conditioning system.

[0053] In a preferred embodiment of the present invention, A / B / C are respectively set to 130Hz / 120Hz / 110Hz, the first frequency range is 110≤Fn<120Hz, the second frequency range is 120≤Fn<130Hz, and the third frequency range is Fn≥130Hz. It should be noted that although specific parameters of A, B, and C are exemplified in the present invention, it should not constitute a limitation. Those skilled in the art can adjust the values of A, B, and C according to actual situations.

[0054] As an example, A / B / C are respectively set to 130Hz / 120Hz / 110Hz, Ps is set to 3.3MPa, a is set to 1.5, b is set to 1.3, c is set to 1.1, and ts is set to 140min. In the cooling mode, after the compressor starts, when it is detected that the actual pressure Pc≥3.3MPa, the timer starts. The compressor frequency operates continuously at a high frequency above 110Hz. The compressor frequency operates at 110Hz≤Fn<120Hz for 30min, at 120Hz≤Fn<130Hz for 30min, and at 130Hz≤Fn until the 46th minute. The calculated virtual oil return duration T = 30*1.1 + 30*1.3 + 46*1.5 = 141, which satisfies the condition of T≥Ts. The air-conditioning system executes the high oil discharge rate oil return correction control logic: the compressor frequency Fn is reduced to the target oil return frequency Fs and operates for a duration of T / 20, and then operates according to the target frequency.

[0055] On the other hand, the present invention provides an air conditioning system that executes the compressor control method of the above-mentioned air conditioning system. Among them, the hardware structure of the air conditioning system is a common application form. For example, in addition to the compressor, it also includes a four-way valve, an indoor heat exchanger, an outdoor heat exchanger, a throttle valve, an indoor fan, an outdoor fan, etc. The air conditioning system can also be a multi-connected air conditioning unit. The air conditioning system includes a compressor control device that executes the above-mentioned compressor control method. The compressor control device includes: a pressure acquisition module that continuously acquires the actual pressure Pc of the air conditioning system in real time. The actual pressure Pc is the high-pressure pressure of the air conditioning system;

[0056] a frequency acquisition module that continuously acquires the actual operating frequency Fn of the compressor in real time;

[0057] a judgment module that, after the compressor starts, judges whether the operating mode of the air conditioning system is the cooling mode; judges whether the actual pressure Pc is greater than the specified pressure threshold Ps; judges whether the actual operating frequency Fn is not less than the first frequency threshold or judges whether the actual operating frequency Fn is in the first frequency range, judges whether the operating frequency Fn is in the second frequency range, judges whether the actual operating frequency Fn is in the third frequency range; and judges whether the virtual oil return duration T is not less than the specified duration threshold Ts;

[0058] a timer that counts the operating duration T1 of the compressor in the first frequency range, the total operating duration T2 of the first frequency range and the second frequency range, and the total operating duration T3 of the first frequency range, the second frequency range and the third frequency range;

[0059] a data processing module that is communicatively connected to the timer. The data processing module calculates the virtual oil return duration according to the operating duration of the compressor in different frequency ranges;

[0060] a control module that is communicatively connected to the judgment module. The control module is configured to: when the actual pressure Pc is greater than the specified pressure threshold Ps, control the timer to start timing; when the actual operating frequency Fn is not less than the first frequency threshold, control the timer to obtain the total operating duration of the actual operating frequency Fn in different frequency ranges respectively; and when the virtual oil return duration T is not less than the specified duration threshold Ts, control the air conditioning system to execute the high oil discharge rate oil return correction control logic.

[0061] Furthermore, the control module is further configured to: when the actual operating frequency Fn is less than the first frequency threshold, control the timer to be cleared. And when executing the high oil discharge rate oil return correction control logic: control the compressor to reduce its frequency to the target oil return frequency Fs and operate for a duration of T / 20, and then operate according to the preset target frequency.

[0062] On the other hand, the present invention provides a computer-readable storage medium storing a computer program, and the computer program executes the compressor control method of the air-conditioning system described above. Specifically, it further includes a processor, and when the computer program is executed by the processor, it executes the compressor control method of the air-conditioning system described above.

[0063] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A compressor control method for an air-conditioning system, characterized in that, The air conditioning system includes a timer, and the compressor control method includes the following steps: S1: After the compressor starts, determine whether the air conditioning system is in the cooling mode; S2: If it is in the cooling mode, collect the actual pressure of the air conditioning system in real time, and when the actual pressure is greater than the specified pressure threshold, control the timer to start timing; S3: Collect the actual operating frequency Fn of the compressor in real time, and when the actual operating frequency Fn is not less than the first frequency threshold C, obtain the total operating duration of the actual operating frequency Fn in different frequency ranges; S4: Calculate the virtual oil return duration according to the total operating duration of the compressor in different frequency ranges; S5: Determine whether the virtual oil return duration T is not less than the specified duration threshold; if the virtual oil return duration T is not less than the specified duration threshold, control the air conditioning system to execute the high oil discharge rate oil return correction control logic, and the high oil discharge rate oil return correction control logic is configured to: control the compressor to reduce the frequency to the target oil return frequency Fs and operate for T / 20 duration and then operate according to the preset target frequency.

2. The compressor control method of the air conditioning system according to claim 1, characterized in that, Before step S1, it also includes: presetting the first frequency threshold C, the second frequency threshold B, and the third frequency threshold A, and the first frequency threshold C, the second frequency threshold B, and the third frequency threshold A increase in sequence.

3. The compressor control method of the air conditioning system according to claim 2, characterized in that, The "obtaining the total operating duration of the actual operating frequency Fn in different frequency ranges" includes: S31: Determine whether the actual operating frequency Fn is in the first frequency range; if the actual operating frequency Fn is in the first frequency range, execute S32; if the judgment result is negative, return to the previous step; S32: Determine whether the operating frequency Fn is in the second frequency range; if the actual operating frequency Fn is in the second frequency range, execute S33, and at the same time the timer marks the total operating duration as T1; if not, return to S31; S33: Determine whether the actual operating frequency Fn is in the third frequency range; if the actual operating frequency Fn is in the third frequency range, execute S34, and at the same time the timer marks the total operating duration as T2; if not, return to S32; S34: The timer marks the total operating duration as T3 in real time, and execute S4; where the first frequency range is C≤Fn<B, the second frequency range is B≤Fn<A, and the third frequency range is Fn≥A.

4. The compressor control method of the air-conditioning system according to claim 3, characterized in that, The virtual oil return duration T = T1*c+(T2 - T1)*b+(T3 - T2)*a, where a, b, and c are constants.

5. The compressor control method of the air-conditioning system according to claim 1, wherein It also includes controlling the timer to be cleared when the actual operating frequency Fn is less than the first frequency threshold.

6. The compressor control method of the air conditioning system according to claim 3, characterized in that, It also includes returning to S1 when the virtual oil return duration T is less than the specified duration threshold.

7. The compressor control method of the air conditioning system according to claim 6, characterized in that, The first frequency range is 110≤Fn<120Hz, the second frequency range is 120≤Fn<130Hz, and the third frequency range is Fn≥130Hz.

8. An air conditioning system, characterized in that, Execute the compressor control method of the air conditioning system according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that, A computer program is stored, and the computer program executes the compressor control method of the air-conditioning system according to any one of claims 1 to 7.

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