CN104879875A - Method for controlling inner devices of multi-device-connected air-conditioning system and multi-device-connected air-conditioning system - Google Patents

Abstract

The invention discloses a method for controlling an internal unit of a multi-connected air-conditioning system and the multi-connected air-conditioning system, which belong to the field of air conditioners and control methods thereof, and are designed to solve the problem that multiple internal units cannot be jointly controlled. The method for controlling the internal units of the multi-connected air-conditioning system of the present invention is to set the levels for multiple internal units respectively, and the system controller controls the opening of the expansion valve of each internal unit respectively to ensure that the internal units with higher levels are preferentially located when the expansion valve opening value is less than The working state of its maximum opening value MaxVal-ij. The multi-connected air-conditioning system of the present invention includes an external unit and at least two internal units, each of which is provided with an expansion valve, and the air-conditioning system also includes a system controller, which is used to detect and control the opening value of the expansion valve of each internal unit . The control method for the internal units of the multi-connected air-conditioning system and the multi-connected air-conditioning system of the present invention can ensure that the internal units with higher grades meet the use requirements preferentially according to the grades, and have reasonable structure, convenient use and wide application range.

Description

Internal unit control method of multi-connected air-conditioning system and multi-connected air-conditioning system

technical field

The invention relates to a method for controlling an internal unit of a multi-connected air-conditioning system and a multi-connected air-conditioning system for realizing the control method.

Background technique

A multi-connected air conditioning system refers to an outdoor unit connected to two or more indoor units. A multi-split air-conditioning system usually consists of indoor units installed in different usage environments. The use environment has great requirements and influence on the effect of the air conditioner of the indoor unit. Taking heating as an example, a sunny room requires much less heating load than a dark and humid room. VIP user rooms have higher requirements for air conditioning effects than ordinary user rooms. heat demand.

Existing multi-connected internal units usually use expansion valves to control the flow of refrigerant entering the heat exchanger of the internal unit from the external unit. Specifically, the opening degree of the expansion valve is calculated according to the coil temperature of the heat exchanger of the internal unit. The spontaneous control of the opening of the expansion valve by the internal unit is only a point control, which cannot realize the individualized effect difference of the internal unit as a whole, and cannot give priority to ensuring the air-conditioning effect of important places.

Contents of the invention

An object of the present invention is to propose a control method for internal units of a multi-connected air-conditioning system that can ensure that high-level internal units meet the use requirements first.

Another object of the present invention is to propose a multi-connected air-conditioning system capable of joint control of multiple indoor units.

For reaching this purpose, on the one hand, the present invention adopts following technical scheme:

A method for controlling internal units of a multi-connected air-conditioning system. The method is to set levels for multiple internal units respectively, and the system controller controls the opening of the expansion valve of each internal unit separately to ensure that the internal units with higher levels are preferentially opened at the expansion valve. The working state where the degree value is less than its maximum opening value MaxVal-ij.

In particular, by reducing the opening of the expansion valve of the low-level internal unit, the opening value of the expansion valve of the high-level internal unit is smaller than its maximum opening value MaxVal-ij.

In particular, the method comprises the steps of:

Step 1. Set the code ij for each indoor unit in the system, where i indicates that the level of this indoor unit is the i-th level, 1≤i≤N, and N is the number of levels of all indoor units; j indicates that the level of this indoor unit The machine is the j-th internal machine in the i-th level, 1≤j≤Mi, and Mi is the number of internal machines in the i-th level;

Step 2. Set the minimum opening value MinVal-ij and the maximum opening value MaxVal-ij for the expansion valve of each internal unit; set the initial value of i to N, and set the initial value of j to 1;

Step 3. Detect whether the opening value of the expansion valve of the ij-th indoor unit is greater than or equal to its maximum opening value MaxVal-ij. If it is greater than or equal to, go to step 4; if it is smaller, go to step 5;

Step 4. Decrease the expansion valve opening of each internal unit in the i-1st stage to the 1st stage, and go to step 3;

Step 5. Judging whether j in step 3 is equal to Mi, if not equal, j is assigned a value of j+1 and goes to step 3; if it is equal, go to step 6;

Step 6. Record the current expansion valve opening value of each internal unit from level i-1 to level 1 as the new maximum opening value MaxVal of the internal unit; assign i to i-1 and j to 1 , go to step 7;

Step 7, judge whether i is equal to 1, if it is equal, go to step 8; if it is not equal, go to step 3;

Step 8, the program ends.

Further, in step 3, the method of reducing the opening degree of the expansion valve of each internal unit in the i-1th stage to the first stage is: open the expansion valve of each internal machine in the i-1th stage to the first stage The degree value is adjusted to K times the current value, where 0<K<1.

Furthermore, the K values corresponding to different grades of internal units are different.

Furthermore, the lower the level of the internal unit, the smaller the corresponding K value.

In particular, no adjustment is made when the opening degree of the expansion valve of the internal unit is the minimum opening value.

In particular, when the system is restarted or restarted, the system controller will sequentially detect whether the expansion valve of each internal unit is working at the maximum opening value according to the order of levels from high to low.

On the other hand, the present invention adopts the following technical solutions:

A multi-connected air-conditioning system for realizing the control method of the above-mentioned internal units, the air-conditioning system includes an external unit and at least two internal units, each internal unit is provided with an expansion valve, the air-conditioning system also includes a system controller, the The system controller described above is used to detect and control the opening value of the expansion valve of each internal unit.

In particular, the system controller is arranged on the external machine.

The control method of the internal unit of the multi-connected air-conditioning system of the present invention is based on the level to ensure that the high-level internal function meets the use requirements first, that is, the high-level internal function is preferentially in the working state where the opening value of the expansion valve is smaller than its maximum opening value MaxVal-ij , the joint adjustment of multiple indoor units makes the allocation of resources (refrigerant) more reasonable, and enables VIP users and other indoor units to work in a more reasonable state in rooms that need to meet the requirements of use. Different levels of internal units correspond to different coefficients K, which can make the adjustment more efficient and bring convenience to the subsequent adjustment of low-level internal units.

The multi-connected air-conditioning system of the present invention realizes the above-mentioned internal machine control method, has a reasonable structure, is convenient to use, and has a wide application range.

Description of drawings

Fig. 1 is a flow chart of a method for controlling an internal unit of a multi-connected air-conditioning system according to a preferred embodiment of the present invention.

Detailed ways

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and through specific implementation methods.

Preferred embodiment one:

This preferred embodiment provides a method for controlling the internal units of a multi-connected air-conditioning system. The method is to set levels for multiple internal units respectively, and the system controller controls the expansion valve opening of each internal unit to ensure high-level internal functions. It is preferentially in the working state where the expansion valve opening value is smaller than its maximum opening value MaxVal-ij. Wherein, by reducing the opening degree of the expansion valve of the low-level internal unit, the opening value of the expansion valve of the high-level internal unit is smaller than its maximum opening value MaxVal-ij.

As shown in Figure 1, the method includes the following steps:

Step 1. Set the code ij for each indoor unit in the system, where i indicates that the level of this indoor unit is the i-th level, 1≤i≤N, and N is the number of levels of all indoor units; j indicates that the level of this indoor unit The machine is the jth internal machine in the i-th level, 1≤j≤Mi, and Mi is the number of internal machines in the i-th level.

The basis for setting the level includes the orientation, floor, area, thermal effect of the room, whether it is a VIP user room, etc. Regardless of whether the air conditioner works in cooling or heating mode, these environmental factors will cause different loads on the internal unit, and user factors will lead to higher or lower requirements for the air conditioner's working effect. Therefore, the level can be set for the internal unit accordingly.

Step 2. Set the minimum opening value MinVal-ij and the maximum opening value MaxVal-ij for the expansion valve of each internal unit; set the initial value of i to N, and set the initial value of j to 1.

The minimum opening value MinVal-ij is a fixed value, such as 200; the initial value of the maximum opening value MaxVal-ij is a fixed value, such as 480, but the maximum opening value MaxVal-ij of each indoor unit will be adjusted later Processes are subject to change. In the system, the minimum opening value MinVal-ij and/or the maximum opening value MaxVal-ij of each indoor unit may be the same or different, depending on actual usage conditions.

Step 3. Detect whether the opening value of the expansion valve of the ij-th indoor unit is greater than or equal to its maximum opening value MaxVal-ij. If it is greater than or equal to, go to step 4; if it is smaller, go to step 5;

Step 4. Decrease the expansion valve opening of each internal unit in the i-1st stage to the 1st stage, and go to step 3. There is no specific method for reducing the expansion valve opening of each internal unit from stage i-1 to stage 1. The preferred method is: reduce the expansion valve opening of each internal unit from stage i-1 to stage 1 The value is adjusted to K times the current value, where 0<K<1. The K values corresponding to different levels of internal units may be the same or different. Preferably, the lower the level of the internal units, the smaller the corresponding K value.

Step 5. Judging whether j in step 3 is equal to Mi, if not equal, j is assigned a value of j+1 and goes to step 3; if it is equal, go to step 6;

Step 6. Record the current expansion valve opening value of each internal unit from level i-1 to level 1 as the new maximum opening value MaxVal of the internal unit; assign i to i-1 and j to 1 , go to step 7;

Step 7, judge whether i is equal to 1, if it is equal, go to step 8; if it is not equal, go to step 3;

Step 8, the program ends.

In order to realize the control method of the above-mentioned indoor unit, this preferred embodiment provides a multi-connected air-conditioning system, the air-conditioning system includes an outdoor unit, a system controller arranged on the outer unit, and at least two inner units; each inner unit is provided with an expansion valve . The system controller is used to detect and control the opening value of the expansion valve of each internal unit. According to the use requirements of each indoor unit, the level of each indoor unit is sequentially set through the interface of the internal unit controller or the external unit control panel. Through the communication mechanism, the external machine can know the level of each internal machine.

The following table shows the two adjustment records of the multi-connected air conditioning system composed of 10 indoor units, and the working mode is heating.

In this multi-connected air-conditioning system, the grade of 0# indoor unit is 7, which is the highest grade; 3# and 8# are both grade 6; the grades of 6# and 22# are both Class 5; 11# indoor unit is class 4; 10# indoor unit is class 3; 15# indoor unit is class 2; 18# and 30# indoor units are both class 1.

Detect the 0# indoor unit with the highest level first. Before the adjustment starts, the opening value of the expansion valve is 370, which is less than the maximum opening value MaxVal, indicating that the air conditioning effect can meet the demand, and there is no need to adjust, and continue to test the next indoor unit.

There is only 0# indoor unit with level 7, so the next test will be level 6 indoor unit. The grades of 3# and 8# indoor units are both grade 6, according to the serial number, first check the 3# indoor unit. Before the adjustment, the opening value of the expansion valve of 3# internal unit was 480, which is the initial value of the maximum opening value MaxVal, indicating that the refrigerant flowing into the 3# internal unit can no longer meet the requirements of its own air conditioning effect, and needs to be adjusted.

The system controller adjusts the opening value of the expansion valves of all internal units of stages 1 to 5. Among them, the opening value of the expansion valve of the 5-stage internal machine is changed to the current value multiplied by the coefficient K=0.99, the opening value of the expansion valve of the 4-stage internal machine is adjusted to the current value multiplied by the coefficient K=0.98, and the opening of the expansion valve of the 3-stage internal machine The value is adjusted to the current value multiplied by the coefficient K=0.97, the opening value of the expansion valve of the second-stage internal unit is adjusted to the current value multiplied by the coefficient K=0.96, and the opening value of the expansion valve of the first-stage internal unit is adjusted to the current value multiplied by the coefficient K= 0.95. In the above table, "—" indicates that the opening value of the expansion valve of the 0# internal unit and the 8# internal unit, both of which are 6 levels, is automatically controlled, and is not adjusted and controlled by the system controller. In addition, the opening value of the 22# internal unit expansion valve of stage 5 has reached the minimum value and is not subject to adjustment by the system controller.

Every once in a while, the external unit re-judges whether the opening value of the 3# internal unit expansion valve at level 6 is less than the maximum opening value MaxVal. If it is still the maximum opening value MaxVal, perform the next adjustment until the opening value of the 3# internal unit expansion valve is less than the maximum opening value MaxVal. If the opening value of the expansion valve of 3# internal unit is 478 after the third adjustment, which is smaller than its maximum opening value of 480, it means that the air conditioning effect of 3# internal unit has been adjusted.

At this time, the opening value of the expansion valve of the 8# internal unit is 320, which is less than the maximum opening value MaxVal, indicating that the air conditioning effect can meet the demand, no adjustment is required, and the next internal unit is tested.

All the internal units of level 6 have met the requirements, and the adjustment of the internal units of level 5 is entered. The grades of 6# and 22# indoor units are both grade 5, and the 6# indoor unit is preferably detected according to the serial number.

The current opening of the 6# indoor unit is 311, which is the new maximum opening value MaxVal formed after the adjustment of the 3# indoor unit, so the 6# indoor unit is currently working at the maximum opening value MaxVal, and the level 1 to 4 needs to be adjusted All internal units. The expansion valve of the 6# internal unit is automatically adjusted, but it cannot exceed the new maximum opening value MaxVal, which is 311.

Each level from 1 to 4 sets a different coefficient K, such as the coefficient K=0.99 for level 4, the coefficient K=0.98 for level 3, the coefficient K=0.97 for level 2, and the coefficient K=0.96 for level 1. Every once in a while, the external unit re-judges whether the expansion valve opening value of the 6# internal unit is less than 311.

If it is still the maximum opening value, carry out the next adjustment until the expansion valve opening value of 6# internal unit is less than the maximum opening value. Assume that after the third adjustment, the expansion valve opening value of 6# internal unit is 308, which is smaller than its maximum opening value of 311, indicating that the 6# internal unit has been adjusted in place, and continue to detect the next internal unit.

The 22# indoor unit works at the minimum opening value MinVal, which means it is sufficient to meet the needs of the air conditioner, no adjustment is required, and the next indoor unit will be tested.

Next is the adjustment of the 4-level internal unit, repeat the above adjustment content. After the adjustment is completed, it can be deduced by analogy until the lowest level internal unit.

When the expansion valve opening of the internal unit is the minimum opening value, no adjustment will be made. When the system is restarted or restarted, the system controller will check whether the expansion valve of each internal unit is working at the maximum opening value in sequence from high to low.

Preferred embodiment two:

This preferred embodiment provides a method for controlling internal units of a multi-connected air-conditioning system and a multi-connected air-conditioning system for realizing the method. The content of the control method and the structure of the air-conditioning system are basically the same as those in the first preferred embodiment. The control method is to set the levels for multiple internal units separately, and the system controller controls the expansion valve opening of each internal unit separately to ensure that the internal units with higher levels are given priority when the expansion valve opening value is less than its maximum opening value MaxVal- The working status of ij. The air conditioning system includes an outdoor unit, a system controller, and at least two inner units; each inner unit is provided with an expansion valve. The system controller is used to detect and control the opening value of the expansion valve of each internal unit.

The difference is: the specific steps of the control method are not limited, as long as the method can be realized; when adjusting the maximum opening value MaxVal of the expansion valve of the low-grade internal unit, the coefficient K can be the same or different according to the grade.

The system controller can be set on the external unit or at other locations. It can timely and accurately set the level for the internal unit, detect the current expansion valve opening value of the internal unit, and adjust the low-level internal unit.

During the adjustment process, the current opening value of the expansion valve of the internal unit whose level is lower than this level can be set as the new maximum opening value after all the internal units in a certain level have been adjusted; After the adjustment, the current opening value of the expansion valve of each internal unit to be adjusted is set as the new maximum opening value.

Claims (10)

1. machine control method in a multi-online air-conditioning system, it is characterized in that, the method to be respectively in multiple stage machine setting grade, the expansion valve opening that system controller controls machine in every platform respectively with ensure grade high in function be preferentially in the duty that expansion valve opening value is less than its maximum opening value MaxVal-ij.

2. machine control method in multi-online air-conditioning system according to claim 1, is characterized in that, by the expansion valve opening reducing low-grade interior machine make high-grade in machine expansion valve opening value be less than its maximum opening value MaxVal-ij.

3. machine control method in multi-online air-conditioning system according to claim 1 and 2, is characterized in that, described method comprises the steps:

Step 1, be in platform every in system machine setting coding ij, wherein, the grade that i characterizes this interior machine is i-th grade, and 1≤i≤N, N is whole interior machine number of degrees; It is machine in jth platform in i-th grade that j characterizes this interior machine, and 1≤j≤Mi, Mi is i-th grade of interior machine number had;

Step 2, set minimum opening value MinVal-ij and maximum opening value MaxVal-ij for the expansion valve of machine in every platform; The initial value arranging i is N, and the initial value arranging j is 1;

Whether step 3, the expansion valve opening value detecting machine in the i-th j platform are more than or equal to its maximum opening value MaxVal-ij, are more than or equal to, go to step 4; Be less than, go to step 5;

Step 4, reduce the expansion valve opening of machine in every platform in the i-th-1 grade to the 1st grade, go to step 3;

In step 5, determining step 3, whether j equals Mi, is not equal to, and j assignment is j+1 and goes to step 3; Equal, go to step 6;

Step 6, expansion valve opening value record current for machine in platform every in the i-th-1 grade to the 1st grade is respectively the new maximum opening value MaxVal of this interior machine; I assignment is i-1, j assignment is 1, goes to step 7;

Step 7, judge whether i equals 1, equals, and goes to step 8; Be not equal to, go to step 3;

Step 8, EP (end of program).

4. machine control method in multi-online air-conditioning system according to claim 3, it is characterized in that, in step 3, the method reducing the expansion valve opening of machine in every platform in the i-th-1 grade to the 1st grade is: the expansion valve opening value of machine in platform every in the i-th-1 grade to the 1st grade is adjusted to the K of currency doubly, wherein, 0 < K < 1.

5. machine control method in multi-online air-conditioning system according to claim 4, is characterized in that, the K value corresponding to interior machine of different brackets is different.

6. machine control method in multi-online air-conditioning system according to claim 5, is characterized in that, the lower grade then corresponding K value of interior machine is less.

7. machine control method in multi-online air-conditioning system according to claim 1 and 2, is characterized in that, then no longer adjusts when the expansion valve opening value of interior machine is minimum opening value.

8. machine control method in multi-online air-conditioning system according to claim 1 and 2, it is characterized in that, after system is again started shooting or restarted, then whether the expansion valve that system controller detects machine in every platform successively according to grade order from high to low is again operated in maximum opening value.

9. one kind for realize as arbitrary in claim 1 to 8 as described in the multi-online air-conditioning system of machine control method, described air-conditioning system comprises outer machine and at least two interior machines, in every platform, machine is provided with expansion valve, it is characterized in that, described air-conditioning system also comprises system controller, and described system controller is used for the opening value of machine expansion valve in the every platform of detection and control.

10. multi-online air-conditioning system according to claim 9, is characterized in that, described system controller is arranged on described outer machine.