WO2017005036A1

WO2017005036A1 - Multi-line apparatus system refrigerant flow control method and device

Info

Publication number: WO2017005036A1
Application number: PCT/CN2016/080246
Authority: WO
Inventors: 罗彬�; 李元阳
Original assignee: 广东美的暖通设备有限公司; 美的集团股份有限公司
Priority date: 2015-07-06
Filing date: 2016-04-26
Publication date: 2017-01-12
Also published as: CN105115199B; EP3182039B1; EP3182039A1; US20170198956A1; EP3182039A4; CN105115199A

Abstract

A multi-line apparatus system refrigerant flow control method and device, the method comprising the following steps: when a multi-line apparatus system enters a main heating mode, controlling a second electronic expansion valve to close; controlling an electronic expansion valve corresponding to a refrigeration internal apparatus to adjust an opening amount thereof; when the opening amount of the electronic expansion valve corresponding to the refrigeration internal apparatus reaches a maximum, calculating a target opening amount of the second electronic expansion valve on the basis of a total opening amount and a maximum opening amount of the electronic expansion valve corresponding to the refrigeration internal apparatus; and controlling the second electronic expansion valve according to target opening amount. The multi-line apparatus system refrigerant bypass control method can ensure a refrigeration effect of a refrigeration internal apparatus in a main heating mode, and at the same time can prevent compressor slugging, ensuring safe and reliable compressor operation.

Description

Refrigerant shunt control method and device for multi-line system

Technical field

The invention relates to the technical field of air conditioners, and in particular to a refrigerant split control method and device for a multi-line system.

Background technique

When the two-regulated heat recovery multi-line system is operated in the main heating mode, some of the refrigerant recooled by the heat exchanger enters the low-pressure pipe of the outdoor unit through the electronic expansion valve and the heat exchanger, and the other part enters through another electronic expansion valve. After the internal heat of the refrigeration unit absorbs heat, it finally enters the low pressure pipe of the outdoor unit.

The opening of the electronic expansion valve affects the refrigerant flow and exhaust superheat entering the refrigerating internal machine. When the flow rate of the refrigerant entering the refrigerating internal machine is lowered due to the improper opening of the electronic expansion valve, the cooling effect of the refrigerating internal machine is affected; when the superheat of the exhaust is lowered due to the improper opening of the electronic expansion valve, This can cause the compressor to slam and cause damage to the compressor.

Summary of the invention

The present invention aims to solve at least one of the technical problems in the related art to some extent. To this end, an object of the present invention is to provide a refrigerant shunt control method for a multi-line system, which can ensure the cooling effect of the refrigerating internal machine in the main heating mode, and at the same time prevent the liquid blow of the compressor and ensure the safety and reliability of the compressor. Run.

A second object of the present invention is to provide a refrigerant split control device for a multi-line system.

A refrigerant shunt control method for a multi-line system according to an embodiment of the first aspect of the present invention, wherein the multi-line system includes a first heat exchanger, a second heat exchanger, a first electronic expansion valve, and a second electronic expansion valve a recooling circuit, and a shunt, the method comprising the steps of: controlling the second electronic expansion valve to close when the multi-line system enters the main heating mode; controlling the electronic expansion valve corresponding to the refrigerating internal machine Opening degree adjustment; when the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine reaches the maximum opening degree, calculating the second electronic expansion according to the total opening degree and the maximum opening degree of the electronic expansion valve corresponding to the refrigerating internal machine a target opening degree of the valve; and performing the second electronic expansion valve according to the target opening degree control.

According to the refrigerant shunt control method of the multi-line system according to the embodiment of the present invention, when the multi-line system enters the main cooling mode, first, the second electronic expansion valve is controlled to be closed, and the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine is controlled, and After the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine reaches the maximum opening degree, the opening degree of the second electronic expansion valve is controlled according to the total opening degree, thereby controlling the refrigerating internal machine by controlling the flow rate of the refrigerant flowing to the refrigerating internal machine The cooling capacity ensures the cooling effect of the internal cooling machine. At the same time, by controlling the total opening degree, the exhaust superheat degree is effectively controlled, thereby preventing the compressor from being hit and ensuring safe and reliable operation of the compressor.

In addition, the refrigerant shunt control method of the multi-line system according to the above embodiment of the present invention may further have the following additional technical features:

In an embodiment of the present invention, the total opening degree is obtained by: obtaining the exhaust superheat when the multi-line system enters the pure heating mode; according to the superheat of the exhaust according to PI (Proportional- The Integral, Proportional Integral algorithm calculates the total opening.

In one embodiment of the present invention, the target opening degree of the second electronic expansion valve is calculated by the following formula: ΔEXV2 = EXV2 (PI) - EV (cold) MAX * (A _{EV (cold)} / A _EXV2 ) Wherein ΔEXV2 is a target opening degree of the second electronic expansion valve, the EXV2 (PI) is the total opening degree, and the EV (cold inner) MAX is an electronic expansion valve corresponding to the refrigeration internal machine The maximum opening degree, the A _{EV (cold inside)} is a valve body flow area of the electronic expansion valve corresponding to the refrigeration internal machine, and the A _EXV2 is a valve body flow area of the second electronic expansion valve.

A refrigerant flow control device for a multiple-line system according to an embodiment of the second aspect of the present invention, wherein the multiple-line system includes a first heat exchanger, a second heat exchanger, a first electronic expansion valve, and a second electronic expansion valve a recooling circuit, and a shunt, the device comprising: a first control module, configured to control the second electronic expansion valve to be closed when the multi-line system enters the main heating mode; the second control module, The electronic expansion valve corresponding to the cooling internal machine is used for adjusting the opening degree; and the calculating module is configured to: when the opening degree of the electronic expansion valve corresponding to the cooling internal machine reaches the maximum opening degree, according to the total opening degree and the cooling inside Calculating a target opening degree of the second electronic expansion valve; and a third control module for controlling the second electronic expansion valve according to the target opening degree.

According to the refrigerant shunt control device of the multi-line system according to the embodiment of the present invention, when the multi-line system enters the main cooling mode, the second electronic expansion valve is controlled to be closed, and the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine is controlled, and the cooling is performed. After the opening degree of the electronic expansion valve corresponding to the internal machine reaches the maximum opening degree, the opening degree of the second electronic expansion valve is controlled according to the total opening degree, thereby controlling the cooling of the refrigerating internal machine by controlling the flow rate of the refrigerant flowing to the refrigerating internal machine The quantity ensures the cooling effect of the internal cooling machine. At the same time, by controlling the total opening degree, the exhaust superheat degree is effectively controlled, thereby preventing the compressor from being hit and ensuring the compressor is safe and reliable. Run.

In addition, the refrigerant shunt control apparatus of the multi-line system according to the above embodiment of the present invention may further have the following additional technical features:

In an embodiment of the present invention, the total opening degree is obtained by: obtaining the exhaust superheat degree when the multi-line system enters the pure heating mode; and calculating according to the PI algorithm according to the exhaust superheat degree The total opening degree.

In one embodiment of the present invention, computing the second target opening degree of the electronic expansion valve by the following formula: ΔEXV2 = EXV2 (PI) -EV ( the cold) MAX * _{(A EV (the cold)} / A _{_EXV2)} Wherein ΔEXV2 is a target opening degree of the second electronic expansion valve, the EXV2 (PI) is the total opening degree, and the EV (cold inner) MAX is an electronic expansion valve corresponding to the refrigeration internal machine The maximum opening degree, the A _{EV (cold inside)} is a valve body flow area of the electronic expansion valve corresponding to the refrigeration internal machine, and the A _EXV2 is a valve body flow area of the second electronic expansion valve.

DRAWINGS

1 is a flow chart of a refrigerant shunt control method for a multi-line system according to an embodiment of the present invention;

2 is a schematic structural diagram of a multi-line system according to an embodiment of the present invention;

3 is a block diagram showing the structure of a refrigerant shunt control apparatus for a multi-line system according to an embodiment of the present invention.

detailed description

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals are used to refer to the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative of the invention and are not to be construed as limiting.

1 is a flow chart of a refrigerant shunt control method for a multi-line system according to an embodiment of the present invention.

In an embodiment of the present invention, as shown in FIG. 2, the multi-line system includes a recooling circuit composed of a first heat exchanger, a second heat exchanger, a first electronic expansion valve, and a second electronic expansion valve, and a shunt Device.

As shown in FIG. 1 , a refrigerant shunt control method for a multi-line system according to an embodiment of the present invention includes the following steps:

S101. When the multi-line system enters the main heating mode, the second electronic expansion valve is controlled to be closed.

S102. Control an electronic expansion valve corresponding to the refrigeration internal machine to perform opening degree adjustment.

Generally, in the pure heating mode, the exhaust superheat of the outdoor unit can be controlled by controlling the opening degree of the second electronic expansion valve, and in the main heating mode, the second electronic expansion valve and the refrigerating internal machine can be controlled. The opening degree of the electronic expansion valve controls the exhaust superheat of the outdoor unit and the flow rate of the refrigerant flowing to the refrigerating machine. Specifically, the second electronic expansion valve can be calculated according to the refrigerant flow rate for cooling required by the refrigerating machine. The opening of the electronic expansion valve corresponding to the refrigeration internal machine. In an embodiment of the present invention, in the main heating mode, the electronic expansion valve corresponding to the refrigeration internal machine can also function as the second electronic expansion valve, that is, the refrigerant passing through the refrigeration internal machine meets the requirements of indoor refrigeration. Then, the refrigerant passing through the refrigerating internal machine is also overheated, so that the effect of preventing the liquid blow of the compressor can be satisfied. Therefore, in this mode, the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine can be preferentially controlled, that is, in step S101. Before controlling the electronic expansion valve corresponding to the refrigeration internal machine to adjust the opening degree, the second electronic expansion valve can be controlled to be closed, and at this time, the superheat of the exhaust of the outdoor unit and the flow rate of the refrigerant flowing to the refrigerating internal machine can be controlled.

S103, when the opening degree of the electronic expansion valve corresponding to the refrigeration internal machine reaches the maximum opening degree, the target opening degree of the second electronic expansion valve is calculated according to the total opening degree and the maximum opening degree of the electronic expansion valve corresponding to the refrigeration internal machine.

When the opening degree of the electronic expansion valve corresponding to the refrigeration internal machine reaches the maximum opening degree, the exhaust superheat of the outdoor unit can no longer be controlled. At this time, the opening degree of the second electronic expansion valve needs to be adjusted to control the exhaust of the outdoor unit. Superheat. Specifically, the target opening degree of the second electronic expansion valve can be calculated by the following formula:

ΔEXV2=EXV2(PI)-EV(cold)MAX*(A _EV(cold) /A _EXV2 ) (1)

Where ΔEXV2 is the target opening degree of the second electronic expansion valve, EXV2 (PI) is the total opening degree, EV (cold inside) MAX is the maximum opening degree of the electronic expansion valve corresponding to the refrigeration internal machine, and A _{EV (cold inside)} is The valve body flow area of the electronic expansion valve corresponding to the refrigeration internal machine, and A _EXV2 is the valve body flow area of the second electronic expansion valve.

Among them, the total opening can be obtained by calculation in the pure heating mode. When the multi-line system enters the pure heating mode, the second electronic expansion valve controls the exhaust superheat, the exhaust temperature, and the return superheat of the outdoor unit to ensure the reliability of the compressor and prevent the compressor from hitting. Specifically, when the multi-line system enters the pure heating mode, the exhaust superheat degree is acquired, and the total opening degree is calculated according to the PI algorithm according to the exhaust superheat degree.

S104. Control the second electronic expansion valve according to the target opening degree.

The second electronic expansion valve can be controlled according to the calculated target opening degree, so that the exhaust superheat of the outdoor unit can be controlled.

According to the refrigerant shunt control method of the multi-line system according to the embodiment of the present invention, when the multi-line system enters the main cooling mode, first, the second electronic expansion valve is controlled to be closed, and the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine is controlled, and After the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine reaches the maximum opening degree, the opening degree of the second electronic expansion valve is controlled according to the total opening degree, thereby controlling the flow of the refrigerant flowing to the refrigerating internal machine The amount of cooling to control the cooling capacity of the internal cooling machine ensures the cooling effect of the internal cooling machine. At the same time, by controlling the total opening degree, the exhaust superheat degree is effectively controlled, thereby preventing the compressor from being hit and ensuring safe and reliable operation of the compressor.

In order to implement the refrigerant shunt control method of the multi-line system of the above embodiment, the present invention also provides a refrigerant shunt control device for a multi-line system.

As shown in FIG. 3, the refrigerant shunt control device of the multi-line system of the embodiment of the present invention includes: a first control module 10, a second control module 20, a calculation module 30, and a third control module 40.

The first control module 10 is configured to control the second electronic expansion valve to be closed when the multi-line system enters the main heating mode. The second control module 20 is configured to control the electronic expansion valve corresponding to the refrigeration internal machine to perform opening degree adjustment.

Generally, in the pure heating mode, the exhaust superheat of the outdoor unit can be controlled by controlling the opening degree of the second electronic expansion valve, and in the main heating mode, the second electronic expansion valve and the refrigerating internal machine can be controlled. The opening degree of the electronic expansion valve controls the exhaust superheat of the outdoor unit and the flow rate of the refrigerant flowing to the refrigerating machine. Specifically, the second electronic expansion valve can be calculated according to the refrigerant flow rate for cooling required by the refrigerating machine. The opening of the electronic expansion valve corresponding to the refrigeration internal machine. In an embodiment of the present invention, in the main heating mode, the electronic expansion valve corresponding to the refrigeration internal machine can also function as the second electronic expansion valve, that is, the refrigerant passing through the refrigeration internal machine meets the requirements of indoor refrigeration. Then, the refrigerant passing through the refrigerating internal machine is also overheated, so that the effect of preventing the liquid hammer of the compressor can be satisfied. Therefore, in this mode, the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine can be preferentially controlled by the second control module 20. That is, before the second control module 20 controls the electronic expansion valve corresponding to the refrigeration internal machine to perform the opening adjustment, the second electronic expansion valve may be controlled to be closed by the first control module 10, and the exhaust superheat of the outdoor unit can still be achieved. And control of the flow of refrigerant to the refrigeration internal machine.

The calculation module 30 is configured to calculate the target opening degree of the second electronic expansion valve according to the total opening degree and the maximum opening degree of the electronic expansion valve corresponding to the refrigeration internal machine when the opening degree of the electronic expansion valve corresponding to the refrigeration internal machine reaches the maximum opening degree. .

When the opening degree of the electronic expansion valve corresponding to the refrigeration internal machine reaches the maximum opening degree, the exhaust superheat of the outdoor unit can no longer be controlled. At this time, the opening degree of the second electronic expansion valve needs to be adjusted to control the exhaust of the outdoor unit. Superheat. Specifically, the calculation module 30 can calculate the target opening degree of the second electronic expansion valve by the following formula:

ΔEXV2=EXV2(PI)-EV(cold)MAX*(A _EV(cold) /A _EXV2 ) (1)

Among them, the total opening can be obtained by calculation in the pure heating mode. When the multi-line system enters the pure heating mode, the second electronic expansion valve controls the exhaust superheat, the exhaust temperature, and the return superheat of the outdoor unit to ensure the reliability of the compressor and prevent the compressor from hitting. Specifically, when the multi-line system enters the pure heating mode, the exhaust superheat degree is acquired, and the total opening degree is calculated according to the PI algorithm according to the exhaust superheat degree. .

The third control module 40 is configured to control the second electronic expansion valve according to the target opening degree.

The third control module 40 can control the second electronic expansion valve according to the calculated target opening degree, so that the exhaust superheat of the outdoor unit can be controlled.

According to the refrigerant shunt control device of the multi-line system according to the embodiment of the present invention, when the multi-line system enters the main cooling mode, the second electronic expansion valve is controlled to be closed, and the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine is controlled, and the cooling is performed. After the opening degree of the electronic expansion valve corresponding to the internal machine reaches the maximum opening degree, the opening degree of the second electronic expansion valve is controlled according to the total opening degree, thereby controlling the cooling of the refrigerating internal machine by controlling the flow rate of the refrigerant flowing to the refrigerating internal machine The quantity ensures the cooling effect of the refrigeration internal machine. At the same time, by controlling the total opening degree, the exhaust superheat degree is effectively controlled, thereby preventing the compressor from being hit and ensuring safe and reliable operation of the compressor.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Rear, Left, Right, Vertical, Horizontal, Top, Bottom, Inner, Out, Clockwise, Counterclockwise, Axial The orientation or positional relationship of the "radial", "circumferential" and the like is based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of describing the present invention and simplifying the description, and does not indicate or imply the indicated device or The elements must have a particular orientation, are constructed and operated in a particular orientation and are therefore not to be construed as limiting.

Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may include one or more of the features either explicitly or implicitly. In the description of the present invention, the meaning of "a plurality" is two or more unless specifically and specifically defined otherwise.

In the present invention, the terms "installation", "connected", "connected", "fixed" and the like shall be understood broadly, and may be either a fixed connection or a detachable, unless otherwise explicitly defined and defined. Unconnected, or integrated; can be mechanically connected or electrically connected; it can be directly connected or indirectly connected through an intermediate medium, which can be the internal communication of two elements or the interaction of two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In the present invention, the first feature "on" or "under" the second feature may be a direct contact of the first and second features, or the first and second features may be indirectly through an intermediate medium, unless otherwise explicitly stated and defined. contact. Moreover, the first feature "above", "above" and "above" the second feature may be that the first feature is directly above or above the second feature, or merely that the first feature level is higher than the second feature. The first feature "below", "below" and "below" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely that the first feature level is less than the second feature.

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means a specific feature described in connection with the embodiment or example. A structure, material or feature is included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms is not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, various embodiments or examples described in the specification, as well as features of various embodiments or examples, may be combined and combined.

Although the embodiments of the present invention have been shown and described, it is understood that the above-described embodiments are illustrative and are not to be construed as limiting the scope of the invention. The embodiments are subject to variations, modifications, substitutions and variations.

Claims

A refrigerant shunt control method for a multi-line system, characterized in that the multi-line system comprises a re-cooling circuit composed of a first heat exchanger, a second heat exchanger, a first electronic expansion valve and a second electronic expansion valve And a shunt, the method comprising the steps of:

Controlling the second electronic expansion valve to close when the multi-line system enters the main heating mode;

Controlling the electronic expansion valve corresponding to the refrigeration internal machine to adjust the opening degree;

When the opening degree of the electronic expansion valve corresponding to the refrigerating internal machine reaches the maximum opening degree, calculating the target opening of the second electronic expansion valve according to the total opening degree and the maximum opening degree of the electronic expansion valve corresponding to the refrigerating internal machine Degree;

The second electronic expansion valve is controlled according to the target opening degree.
The refrigerant shunt control method for a multi-line system according to claim 1, wherein the total opening degree is obtained by the following steps:

Obtaining exhaust superheat when the multi-line system enters the pure heating mode;

The total opening degree is calculated according to the PI algorithm according to the exhaust superheat degree.
The refrigerant shunt control method for a multiple-line system according to claim 1, wherein the target opening degree of the second electronic expansion valve is calculated by the following formula:

ΔEXV2=EXV2(PI)-EV (cold)MAX*(A EV(cold) /A EXV2 ), wherein the ΔEXV2 is a target opening degree of the second electronic expansion valve, the EXV2 (PI) For the total opening degree, the EV (cold inner) MAX is the maximum opening degree of the electronic expansion valve corresponding to the refrigeration internal machine, and the A EV (cold inner) is the valve body circulation of the electronic expansion valve corresponding to the refrigeration internal machine. The area, the A EXV2 is a valve body flow area of the second electronic expansion valve.
A refrigerant split control device for a multi-line system, characterized in that the multiple-line system comprises a re-cooling circuit composed of a first heat exchanger, a second heat exchanger, a first electronic expansion valve and a second electronic expansion valve And a shunt, the device comprising:

a first control module, configured to control the second electronic expansion valve to be closed when the multiple online system enters the main heating mode;

a second control module, configured to control an opening of the electronic expansion valve corresponding to the refrigeration internal machine;

a calculation module, configured to calculate the second electron according to a total opening degree and a maximum opening degree of the electronic expansion valve corresponding to the refrigerating internal machine when an opening degree of the electronic expansion valve corresponding to the refrigerating internal machine reaches a maximum opening degree The target opening of the expansion valve;

And a third control module, configured to control the second electronic expansion valve according to the target opening degree.
A refrigerant flow control device for a multiple-line system according to claim 4, wherein said total opening degree is obtained by the following steps:

Obtaining exhaust superheat when the multi-line system enters the pure heating mode;

The total opening degree is calculated according to the PI algorithm according to the exhaust superheat degree.
A refrigerant flow control device for a multiple-line system according to claim 4, wherein the target opening degree of said second electronic expansion valve is calculated by the following formula:

ΔEXV2=EXV2(PI)-EV (cold)MAX*(A EV(cold) /A EXV2 ), wherein the ΔEXV2 is a target opening degree of the second electronic expansion valve, the EXV2 (PI) For the total opening degree, the EV (cold inner) MAX is the maximum opening degree of the electronic expansion valve corresponding to the refrigeration internal machine, and the A EV (cold inner) is the valve body circulation of the electronic expansion valve corresponding to the refrigeration internal machine. The area, the A EXV2 is a valve body flow area of the second electronic expansion valve.