CN111102677B - Control method and control system for load balance of double compressors and air conditioner - Google Patents

Abstract

Translated fromChinese

本发明涉及一种双压缩机负荷平衡的控制方法、控制系统及空调，其中，双压缩机负荷平衡的控制方法包括：分别实时检测第一压缩机的运行电流I₁，第二压缩机的运行电流I₂；判断运行电流I₁和I₂与第一预设电流值的关系；如果运行电流I₁和I₂满足：|I₁‑I₂|＞第一预设电流值且持续第一时间t₁，则分别调节第一压缩机的运行频率f₁、第二压缩机的运行频率f₂，以使第一压缩机与第二压缩机之间的负荷平衡。本发明通过检测双压缩机的电流，当双压缩机的电流不均衡时，通过调节双压缩机的运行频率，以使双压缩机之间的负荷平衡，从而减少压缩机的磨损，延长压缩机的寿命，以及减少元器件的电应力损伤，降低元器件失效的概率。

The invention relates to a control method, a control system and an air conditioner for load balancing of dual compressors, wherein the control method for load balancing_of dual compressors comprises: Current I₂ ; determine the relationship between the running currents I₁ and I₂ and the first preset current value; if the running currents I₁ and I₂ satisfy: |I₁ -I₂ |> the first preset current value and continue for the first At time t₁ , the operating frequency f₁ of the first compressor and the operating frequency f₂ of the second compressor are adjusted respectively, so as to balance the load between the first compressor and the second compressor. The invention detects the current of the dual compressors, and adjusts the operating frequency of the dual compressors when the currents of the dual compressors are unbalanced to balance the load between the dual compressors, thereby reducing the wear of the compressors and prolonging the compressor life. life, and reduce the electrical stress damage of components and reduce the probability of component failure.

Description

Control method and control system for load balance of double compressors and air conditioner

Technical Field

The invention relates to the technical field of air conditioners, in particular to a control method and a control system for load balance of double compressors and an air conditioner.

Background

The compressor of the big cold volume of present air conditioner, adopt the parallelly connected mode of two compressors or a plurality of compressors to realize powerful refrigeration usually, when adopting two compressors parallel operation under same operating frequency, because influence factors such as difference and pipeline welding processing difference between each compressor, can lead to the phenomenon of unbalanced load to appear between the two compressors, the operating current to the higher compressor of load also can be bigger than normal, if the compressor is in higher load operation for a long time, can shorten the life-span of compressor, can lead to compressor wearing and tearing even damage, the temperature rise of the components and parts of the controller of compressor also can be higher than normal simultaneously, thereby increase the probability that components and parts became invalid.

Disclosure of Invention

In order to solve the above technical problem, a first aspect of the present invention provides a method for controlling load balancing of two compressors, the method comprising: respectively detecting the running current I of the first compressor in real time₁Operating current I of the second compressor₂(ii) a Judging the running current I₁And I₂A relation to a first preset current value; if the operating current I₁And I₂Satisfies the following conditions: i₁-I₂If greater than the first preset current value and lasting for a first time t₁Respectively adjusting the operating frequency f of said first compressor₁The operating frequency f of the second compressor₂To balance the load between the first compressor and the second compressor.

The invention detects the current of the double compressors and converts the running current I of the double compressors₁And I₂The absolute value of the difference is compared with a first preset current value when the running current I of the two compressors₁And I₂When the absolute value of the difference between the two compressors is larger than a first preset current value, the operating frequency of the two compressors is adjusted to balance the load between the two compressors, so that the abrasion of the compressors is reduced, the service life of the compressors is prolonged, the electrical stress damage of components is reduced, and the failure probability of the components is reduced.

Further, the detecting and determining step further includes: detecting system pressure P of the first compressor and the second compressor in real time; if the system pressure P satisfies: p is larger than a second preset pressure value and lasts for a second time t₂Then further judging the running current I₁And I₂A relation with the first preset current value.

According to the invention, the system pressure of the double compressors is detected instead of the pressure of each compressor, so that on one hand, the detection mode is simple and effective, and on the other hand, the accuracy of judging the load unbalance of the double compressors is enhanced.

Further, the judging step further includes: judging the running current I₁And I₂Respectively, with a third preset value, if I₁The third preset current value lasts for a third time t₃Or I₂The third preset current value lasts for a third time t₃Then further judging the running current I₁And I₂A relation with the first preset current value.

The invention not only detects the system pressure of the double compressors, but also compares the current of the double compressors with a third preset current value respectively, thereby judging the load size of the double compressors, further facilitating the adjustment to ensure that the double compressors realize load balance, prolonging the service life of the double compressors, reducing the electrical stress damage of components and reducing the failure probability of the components.

Further, the adjusting step specifically includes: if the operating current I₁And I₂Satisfies the following conditions: i is₁＞I₂Then the operating frequency f of said first compressor₁Reducing a fourth preset frequency adjustment value DeltaF, the operating frequency F of the second compressor₂Raising said fourth preset frequency adjustment value af; or if the operating current I₁And I₂Satisfies the following conditions: i is₁＜I₂Then the operating frequency f of said first compressor₁Raising the fourth preset frequency adjustment value DeltaF, the operating frequency F of the second compressor₂And reducing the fourth preset frequency adjustment value deltaF.

The invention reduces the operation frequency of the compressor with large operation current, increases the operation frequency of the compressor with small operation current, adjusts the load of the double compressors, and ensures that the total output is unchanged, thereby prolonging the service life of the compressor, reducing the electrical stress damage of the controller components and reducing the damage of the components.

Further, the operating current I is set to be the operating current I if the adjusting step is completed₁And I₂Satisfies the following conditions: i is₁≤I₂Ending the adjusting step; or if the operating current I₁And I₂Satisfies the following conditions: i is₁≥I₂The adjusting step is ended.

The invention judges the relation between the running currents after adjusting the running frequency so as to prevent the infinite circulation of the adjusting running frequency.

Further, the value range of the fourth preset frequency adjustment value Δ F is 3Hz to 10 Hz.

The control system for load balance of the double compressors comprises an acquisition unit for acquiring the running current I of the first compressor in real time₁And the operating current I of the second compressor₂(ii) a A judging unit for judging the operation current I of the first compressor₁And the operating current I of the second compressor₂A relationship with the first preset current value; a control unit for controlling the operating frequency f of the first compressor₁The operating frequency f of the second compressor₂And (6) carrying out adjustment.

Further, the acquiring unit is further configured to acquire a system pressure P of the dual compressor.

A third aspect of the present invention provides an air conditioner comprising the above dual-compressor load balancing control system.

Drawings

Fig. 1 is a schematic flow chart of a control method for load balancing of two compressors according to an embodiment of the present invention;

fig. 2 is a schematic flow chart of a control method for load balancing of two compressors according to a second embodiment of the present invention;

fig. 3 is a schematic flow chart of a control method for load balancing of two compressors according to a third embodiment of the present invention;

fig. 4 is a schematic flow chart of a control method for load balancing of two compressors according to the fourth embodiment of the present invention;

description of reference numerals:

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures 1 to 4 are described in detail below.

Implementation mode one

Referring to fig. 1, a first aspect of the present invention provides a method for controlling load balancing of a dual compressor, including: when the two compressors are both in the running state, the running current I of the first compressor is respectively detected in real time₁Operating current I of the second compressor₂(ii) a Judging the operating current I₁And I₂A relation to a first preset current value; if the running current I₁And I₂Satisfies the following conditions: i₁-I₂If greater than the first preset current value and lasting for the first time t₁Then the operating frequency f of the first compressor is adjusted separately₁The operating frequency f of the second compressor₂To balance the load between the first and second compressors.

Wherein, the value range of the first preset current value is 3A-10A, and the first time t₁The value range of (A) is 30 s-10 min.

Therefore, the invention detects the current of the double compressors and converts the running current I of the double compressors₁And I₂The absolute value of the difference is compared with a first preset current value when the running current I of the two compressors₁And I₂When the absolute value of the difference between the two compressors is larger than a first preset current value, the operating frequency of the two compressors is adjusted to balance the load between the two compressors, so that the abrasion of the compressors is reduced, the service life of the compressors is prolonged, the electrical stress damage of components is reduced, and the failure probability of the components is reduced.

Second embodiment

Referring to fig. 2, the method for controlling the load balancing of the dual compressors according to the present embodiment basically adopts the same steps as those of the first embodiment.

Different from the first embodiment, the detecting and determining step further includes: detecting first compression in real timeSystem pressure P of the machine and the second compressor; if the system pressure P satisfies: p is larger than a second preset pressure value and lasts for a second time t₂Then further judging the running current I₁And I₂A relation with a first preset current value.

Wherein the value range of the second preset pressure value is 3.5 MPa-4 MPa, and the second time t is₂The value range of (A) is 30 s-30 min.

Therefore, the system pressure of the double compressors is detected instead of the pressure of each compressor, so that the detection mode is simple and effective on one hand, and the accuracy of judging the load unbalance of the double compressors is enhanced on the other hand.

Third embodiment

Referring to fig. 3, the method for controlling the load balancing of the dual compressors according to the present embodiment basically adopts the same steps as those of the second embodiment.

Different from the second embodiment, the determining step further includes: judging the operating current I₁And I₂Respectively with a third preset current value, the third preset current value is the maximum operation current value, the first if I₁Is greater than a third preset current value and lasts for a third time t₃Or I₂Is greater than a third preset current value and lasts for a third time t₃Then further judging the running current I₁And I₂A relation with a first preset current value.

Wherein the third preset current value is 20A-38A, and the third time t₃Is 30 s-30 min.

When the system pressure of the two compressors is larger, the operation current of at least one of the two corresponding compressors is also larger, so that the operation current I of the first compressor is further judged₁And the operating current I of the second compressor₂And the magnitude relation with the third preset current value further determines that the load of the compressor is larger.

Therefore, the invention not only detects the system pressure of the double compressors, but also compares the current of the double compressors with the third preset current value respectively, thereby judging the load of the double compressors, further facilitating the adjustment to ensure that the double compressors realize load balance, prolonging the service life of the double compressors, reducing the electrical stress damage of components and reducing the failure probability of the components.

Embodiment IV

Referring to fig. 4, the method for controlling the load balancing of the dual compressors according to the present embodiment basically adopts the same steps as those of the first, second or third embodiment.

Different from the first, second or third embodiment, the adjusting step specifically includes: if the running current I₁And I₂Satisfies the following conditions: i is₁＞I₂Then the operating frequency f of the first compressor₁Reducing the fourth preset frequency adjustment value DeltaF, the operating frequency F of the second compressor₂Increasing a fourth preset frequency adjustment value delta F; or if the operating current I₁And I₂Satisfies the following conditions: i is₁＜I₂Then the operating frequency f of the first compressor₁Raising the fourth preset frequency adjustment value DeltaF, the operating frequency F of the second compressor₂And reducing the fourth preset frequency adjustment value delta F.

Therefore, the invention adopts the compressor with large running current to reduce the running frequency, increases the running frequency of the compressor with small running current, adjusts the load of the double compressors and ensures that the total output is unchanged, thereby prolonging the service life of the compressor, simultaneously reducing the electrical stress damage of the controller components and reducing the damage of the components.

Referring to FIG. 4, if the operating current I₁And I₂Satisfies the following conditions: i is₁＞I₂Then the operating frequency f of the first compressor₁Reducing the fourth preset frequency adjustment value DeltaF, the operating frequency F of the second compressor₂Increasing a fourth preset frequency adjustment value delta F; after the adjustment step is performed, if the current I is running₁And I₂Satisfies the following conditions: i is₁≤I₂If yes, ending the adjusting step;

or if the operating current I₁And I₂Satisfies the following conditions: i is₁＜I₂Then the operating frequency f of the first compressor₁Raising the fourth preset frequency adjustment value deltaF, second compressingOperating frequency f of the machine₂Reducing a fourth preset frequency adjustment value delta F; after the adjustment step is performed, if the current I is running₁And I₂Satisfies the following conditions: i is₁≥I₂The adjusting step is ended.

Wherein, the value range of the fourth preset frequency adjusting value delta F is 3 Hz-10 Hz.

Therefore, the invention judges the relation between the running currents after adjusting the running frequency so as to prevent the operation frequency from being adjusted to be infinitely circulated.

The second aspect of the invention provides a control system for load balancing of two compressors, and the control method comprises an acquisition unit for acquiring the running current I of the first compressor in real time₁And the operating current I of the second compressor₂And a system pressure P for acquiring the dual compressors; a judging unit for judging the operation current I of the first compressor₁And the operating current I of the second compressor₂A relation to a first preset current value; a control unit for controlling the operating frequency f of the first compressor₁The operating frequency f of the second compressor₂And (6) carrying out adjustment.

A third aspect of the present invention provides an air conditioner comprising the above dual-compressor load balancing control system.

Although the present invention is disclosed above, the present invention is not limited thereto. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (8)

Translated fromChinese

1.一种双压缩机负荷平衡的控制方法，其特征在于，所述方法包括：1. A control method for dual compressor load balance, wherein the method comprises:实时检测第一压缩机和第二压缩机的系统压力P以及分别实时检测第一压缩机的运行电流I₁和第二压缩机的运行电流I₂；Detecting the system pressure P of the first compressor and the second compressor in real time and detecting the operating current I₁ of the first compressor and the operating current I₂ of the second compressor respectively in real time;如果所述系统压力P满足：P＞第二预设压力值且持续第二时间t₂，则进一步判断所述运行电流I₁和I₂与第一预设电流值的关系；If the system pressure P satisfies: P>the second preset pressure value for a second time t₂ , further determine the relationship between the operating currents I₁ and I₂ and the first preset current value;如果所述运行电流I₁和I₂满足：|I₁-I₂|＞第一预设电流值且持续第一时间t₁，则分别调节所述第一压缩机的运行频率f₁和所述第二压缩机的运行频率f₂，以使所述第一压缩机与所述第二压缩机之间的负荷平衡。If the operating currents I₁ and I₂ satisfy: |I₁ -I₂ |>the first preset current value for a first time t₁ , then adjust the operating frequency f₁ and all of the first compressors respectively. The operating frequency f₂ of the second compressor is adjusted to balance the load between the first compressor and the second compressor.2.根据权利要求1所述的双压缩机负荷平衡的控制方法，其特征在于，判断步骤还包括：2. The control method for dual compressor load balance according to claim 1, wherein the judging step further comprises:判断所述运行电流I₁和I₂分别与第三预设电流值的关系，如果I₁＞所述第三预设电流值且持续第三时间t₃，或I₂＞所述第三预设电流值且持续第三时间t₃，则进一步判断所述运行电流I₁和I₂与所述第一预设电流值的关系。Judging the relationship between the operating currents I₁ and I₂ and the third preset current value, if I₁ > the third preset current value for a third time t₃ , or if I₂ > the third preset current value Set the current value and last for a third time t₃ , then further determine the relationship between the operating currents I₁ and I₂ and the first preset current value.3.根据权利要求1或2所述的双压缩机负荷平衡的控制方法，其特征在于，3. The control method of dual compressor load balance according to claim 1 or 2, wherein,所述调节所述第一压缩机的运行频率f₁和所述第二压缩机的运行频率f₂，以使所述第一压缩机与所述第二压缩机之间的负荷平衡的步骤具体包括：The step of adjusting the operating frequency f₁ of the first compressor and the operating frequency f₂ of the second compressor so as to balance the load between the first compressor and the second compressor is concrete include:如果所述运行电流I₁和I₂满足：I₁＞I₂，则控制所述第一压缩机的运行频率f₁降低第四预设频率调节值△F，所述第二压缩机的运行频率f₂升高所述第四预设频率调节值△F；If the operating currents I₁ and I₂ satisfy: I₁ >I₂ , the operating frequency f₁ of the first compressor is controlled to decrease by a fourth preset frequency adjustment value ΔF, and the operation of the second compressor_The frequency f2 is increased by the fourth preset frequency adjustment value ΔF;或如果所述运行电流I₁和I₂满足：I₁＜I₂，则控制所述第一压缩机的运行频率f₁升高所述第四预设频率调节值△F，所述第二压缩机的运行频率f₂降低第四预设频率调节值所述△F。Or if the operating currents I₁ and I₂ satisfy: I₁ <I₂ , the operating frequency f₁ of the first compressor is controlled to increase the fourth preset frequency adjustment value ΔF, and the second_The operating frequency f2 of the compressor is reduced by the fourth preset frequency adjustment value by the ΔF.4.根据权利要求3所述的双压缩机负荷平衡的控制方法，其特征在于，4. The control method of dual compressor load balance according to claim 3, wherein,如果所述运行电流I₁和I₂满足：I₁＞I₂，则控制所述第一压缩机的运行频率f₁降低第四预设频率调节值△F，所述第二压缩机的运行频率f₂升高所述第四预设频率调节值△F之后，如果所述运行电流I1和I₂满足：I₁≤I₂,则结束调节步骤；If the operating currents I₁ and I₂ satisfy: I₁ >I₂ , the operating frequency f₁ of the first compressor is controlled to decrease by a fourth preset frequency adjustment value ΔF, and the operation of the second compressor After the frequency f2 is increased by the fourth preset frequency adjustment value ΔF, if the operating currents_I1 and_I2 satisfy:_I1≤I2 , the adjustment step is ended_;或如果所述运行电流I₁和I₂满足：I₁＜I₂，则控制所述第一压缩机的运行频率f₁升高所述第四预设频率调节值△F，所述第二压缩机的运行频率f₂降低第四预设频率调节值所述△F之后，如果所述运行电流I₁和I₂满足：I₁≥I₂,则结束所述调节步骤。Or if the operating currents I₁ and I₂ satisfy: I₁ <I₂ , the operating frequency f₁ of the first compressor is controlled to increase the fourth preset frequency adjustment value ΔF, and the second After the operating frequency f₂ of the compressor is reduced by the fourth preset frequency adjustment value ΔF, if the operating currents I₁ and I₂ satisfy: I₁ ≥ I₂ , the adjustment step is ended.5.根据权利要求2所述的双压缩机负荷平衡的控制方法，其特征在于，所述第一预设电流值的取值范围为3A~10A，所述第一时间t₁的取值范围为30s~10min，所述第二预设压力值的取值范围为3.5MPa~4MPa，所述第二时间t₂的取值范围为30s~30min，所述第三预设电流值为20A~38A，所述第三时间t₃为30s~30min。5. The method for controlling the load balance of dual compressors according to claim 2, wherein the value range of the first preset current value is 3A~10A, and the value range of the first time_t1 is 30s~10min, the value range of the second preset pressure value is 3.5MPa~4MPa, the value range of the second time_t2 is 30s~30min, and the third preset current value is 20A~ 38A, the third time_t3 is 30s˜30min.6.根据权利要求3所述的双压缩机负荷平衡的控制方法，其特征在于，所述第四预设频率调节值△F的取值范围为3Hz~10Hz。6 . The method for controlling the load balance of dual compressors according to claim 3 , wherein the value range of the fourth preset frequency adjustment value ΔF is 3 Hz to 10 Hz. 7 .7.一种双压缩机负荷平衡的控制系统，应用权利要求1-6中任一项所述的控制方法，其特征在于，包括：7. A control system for dual compressor load balance, applying the control method according to any one of claims 1-6, characterized in that, comprising:获取单元，用于实时获取所述第一压缩机和第二压缩机的系统压力P以及所述第一压缩机的运行电流I₁和所述第二压缩机的运行电流I₂；an acquisition unit, configured to acquire the system pressure P of the first compressor and the second compressor and the operating current I₁ of the first compressor and the operating current I₂ of the second compressor in real time;判断单元，用于判断所述系统压力P和所述第二预设压力值的关系以及所述第一压缩机的运行电流I₁和所述第二压缩机的运行电流I₂与所述第一预设电流值的关系；A judging unit for judging the relationship between the system pressure P and the second preset pressure value, the operating current_I1 of the first compressor, the operating current I2 of the_second compressor and the first compressor a preset current value relationship;控制单元，用于对所述第一压缩机的运行频率f₁、所述第二压缩机的运行频率f₂进行调节。A control unit, configured to adjust the operating frequency f₁ of the first compressor and the operating frequency f₂ of the second compressor.8.一种空调，其特征在于，包括权利要求7所述的双压缩机负荷平衡的控制系统。8. An air conditioner, characterized by comprising the dual compressor load balancing control system of claim 7.

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