A regional temperature control method and system based on variable frequency outdoor unit requirements

Abstract

The present invention discloses a regional temperature control method and system based on the demand of variable frequency outdoor unit. The method comprises the following steps: obtaining the regional type of the area where the air-conditioning system is located; according to the regional type, controlling the opening of the fresh air valve and the return air valve of the air-conditioning system, as well as the initial opening number of the variable frequency outdoor unit; obtaining the current indoor temperature of the area where the air-conditioning system is located, and performing a logical operation based on the difference between the preset temperature and the current indoor temperature to calculate the current demand of a single variable frequency outdoor unit; for different areas, according to the current total demand of the air-conditioning system, the initial opening number of the variable frequency outdoor unit and the current demand of the single variable frequency outdoor unit, executing the preset first load reduction logic, the first loading logic, the second load reduction logic or the second loading logic, so as to realize regional temperature control. Thus, the variable frequency outdoor unit is prevented from working under extreme working conditions, and the long-term stable operation of the air-conditioning system is ensured.

Description

Technical Field

[0001] The invention relates to a regional temperature control method based on the requirements of a variable frequency outdoor unit, and also relates to a corresponding regional temperature control system, belonging to the technical field of air conditioning. Background Art

[0002] Multi-split air conditioning systems are widely used because they can meet the cooling and heating needs of large venues such as office buildings, hospitals and data centers. This air conditioning system consists of multiple interconnected outdoor unit modules that can share refrigerant and dynamically adjust the operation of each outdoor unit module according to the load of the indoor unit.

[0003] However, the control strategy commonly used by existing air-conditioning systems on the market is: first make one outdoor unit reach the maximum operating frequency, and if there is still additional demand, continue to load another outdoor unit until all outdoor units are loaded. This method may cause some outdoor units to operate at the maximum frequency, while other outdoor units operate at a low frequency, causing large fluctuations in air parameters, especially when the set temperature and humidity change. In addition, the compressors may operate under extreme conditions, some at the maximum frequency and some at a lower frequency, which makes it difficult to maintain long-term stable cooling and heating effects.

[0004] Therefore, a reliable optimization method and control strategy are urgently needed to solve these problems and ensure the long-term stable operation of the air-conditioning system. Summary of the invention

[0005] The primary technical problem to be solved by the present invention is to provide a regional temperature control method based on the requirements of a variable frequency outdoor unit.

[0006] Another technical problem to be solved by the present invention is to provide a regional temperature control system based on the requirements of a variable frequency outdoor unit.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] According to a first aspect of an embodiment of the present invention, there is provided a regional temperature control method based on the requirements of a variable frequency outdoor unit, comprising the following steps:

[0009] Obtaining the area type of the area where the air conditioning system is located; wherein the air conditioning system is composed of an indoor unit and a plurality of variable frequency outdoor units; the area type at least includes a theater auditorium area, a hospital shopping mall area or a data room area;

[0010] According to the zone type, the opening of the fresh air valve and the opening of the return air valve of the air conditioning system, as well as the initial opening number n of the variable frequency outdoor unit are controlled; wherein the opening of the fresh air valve, the opening of the return air valve and the initial opening number n of the variable frequency outdoor unit corresponding to different zone types are all different, and n is a positive integer;

[0011] Obtaining the current indoor temperature of the area where the air conditioning system is located, and performing a logical operation based on the difference between the preset temperature and the current indoor temperature to calculate the current demand of a single variable frequency outdoor unit;

[0012] Calculating the total current demand of the air conditioning system based on the current demand of the single variable frequency outdoor unit and the total number of the variable frequency outdoor units;

[0013] In the theater auditorium area, according to the current total demand of the air-conditioning system and the initial number of the variable frequency outdoor units turned on, the preset first load reduction logic is executed to gradually reduce the load of the variable frequency outdoor unit with the longest running time until all the variable frequency outdoor units are completely shut down; in the hospital shopping mall area, according to the current demand of the single variable frequency outdoor unit, the preset first loading logic or the second load reduction logic is executed to gradually load the variable frequency outdoor unit or the variable frequency outdoor unit with the longest load reduction running time until all the variable frequency outdoor units are completely shut down; in the data room area, according to the current total demand of the air-conditioning system and the initial number n of the variable frequency outdoor units turned on, the second loading logic or the first load reduction logic is executed to gradually load the variable frequency outdoor unit or the variable frequency outdoor unit with the longest load reduction running time until all the variable frequency outdoor units are completely shut down.

[0014] Preferably, obtaining the area type of the area where the air conditioning system is located specifically includes:

[0015] The air conditioning system is put into trial operation, with the fresh air valve closed and the return air valve opened, and the corresponding number of variable frequency outdoor units are started according to half of the total number for a preset time period;

[0016] During the trial operation of the air conditioning system, corresponding detection data is obtained based on a CO2 sensor pre-installed in the unit; wherein the CO2 sensor has pre-set normal data;

[0017] Acquire the data change trend of the CO2 sensor according to the detection data and normal data of the CO2 sensor;

[0018] According to the data change trend of the CO2 sensor, the area type of the area where the air conditioning system is located is obtained;

[0019] Among them, when the data change trend is no obvious change, the area is judged to be a data room area; when the data change trend is a rapid increase in value, the area is judged to be a theater auditorium area; when the data change trend is a slow increase in value, the area is judged to be a hospital shopping mall area.

[0020] Preferably, after the air conditioning system passes the regional judgment, it keeps running according to the control mode of the corresponding region, and performs regional judgment once every preset time interval thereafter;

[0021] When the data change trend of the area is judged to be no obvious change, the control mode corresponding to the original area is maintained and continued to operate;

[0022] When the data change trends of two consecutive regional judgments are both downward and the decline reaches a preset level, switch to the control mode corresponding to the data room area.

[0023] Preferably, the first load reduction logic specifically includes:

[0024] According to the initial start-up number n of the variable frequency outdoor machines, the expected total demand of n variable frequency outdoor machines is calculated; wherein each of the variable frequency outdoor machines is preset with the same expected demand;

[0025] The current indoor temperature of the area where the air-conditioning system is located is collected once at a preset time interval, and a logical operation is performed based on the difference between the preset temperature and the current indoor temperature to update the current demand of a single variable frequency outdoor unit, and then update the current total demand of the air-conditioning system;

[0026] Determining whether the current total demand of the air-conditioning system is less than the expected total demand of n-1 variable frequency outdoor units;

[0027] If it is less than, then reduce the load of the variable frequency outdoor unit with the longest running time; if it is not less than, then keep n variable frequency outdoor units running at full load until the current total demand of the air-conditioning system is less than the expected total demand of n-1 variable frequency outdoor units;

[0028] Repeat the above process until all variable frequency outdoor units are turned off.

[0029] Preferably, the first loading logic specifically includes:

[0030] After n of the variable frequency outdoor units have been running for a preset time, the current indoor temperature of the area where the air conditioning system is located is collected, and a logical operation is performed based on the difference between the preset temperature and the current indoor temperature to update the current demand of a single variable frequency outdoor unit;

[0031] Determine whether the current demand of the updated single variable frequency outdoor unit is less than the preset load reduction threshold;

[0032] If it is less than, stop loading the variable frequency external machine and execute the second load reduction logic; if it is not less than, load a variable frequency external machine, and update the current demand of the single variable frequency external machine again based on n+1 variable frequency external machines, until the updated current demand of the single variable frequency external machine is less than the preset load reduction threshold.

[0033] Preferably, the second load reduction logic specifically includes:

[0034] If the current demand of a single variable-frequency outdoor unit after the update is less than the preset load reduction threshold, the frequency of all variable-frequency outdoor units under the current quantity will be synchronously reduced;

[0035] When all the variable frequency outdoor units are synchronously reduced to the lower frequency limit and continue to run for more than the second preset time, the load of the variable frequency outdoor unit with the longest running time is reduced.

[0036] Preferably, the second loading logic specifically includes:

[0037] Arrange multiple preset loading thresholds in ascending order;

[0038] According to the arrangement order of the plurality of preset loading thresholds, sequentially comparing the current total demand of the air conditioning system with the respective preset loading thresholds;

[0039] If the current total demand of the air-conditioning system is not less than the preset loading threshold value of the current comparison, one variable frequency outdoor unit is loaded; otherwise, the loading is stopped.

[0040] Preferably, in the theater auditorium area, the opening of the fresh air valve is 0, the opening of the return air valve is 100%, and the initial opening number n of the variable frequency outdoor units is the total number of variable frequency outdoor units; in the hospital shopping mall area, the opening of the fresh air valve is 70%, the opening of the return air valve is 30%, and the initial opening number n of the variable frequency outdoor units is half of the total number of variable frequency outdoor units; in the data room area, the opening of the fresh air valve is 20%, the opening of the return air valve is 80%, and the initial opening number n of the variable frequency outdoor units is 0.

[0041] Preferably, the current demand of the single variable frequency external machine is calculated by the following formula:

[0042] u(k)=Kp e(k)+Ki ∑[e(0)…e(k-1)]+Kd [e(k)…e(k-1)]

[0043] Among them, u(k) represents the current demand calculated by a single variable frequency outdoor unit for the kth time; Kp represents the proportional coefficient, Ki represents the integral coefficient, Kd represents the differential coefficient, and Kp, Ki and Kd are preset according to different area types; e(k) represents the difference between the current indoor temperature sampled for the kth time and the preset temperature; k = 0, 1, 2, 3..., represents the sampling sequence number.

[0044] According to a second aspect of an embodiment of the present invention, there is provided a sub-region temperature control system for implementing the above-mentioned sub-region temperature control method, comprising:

[0045] A region selection module is used to obtain the region type of the region where the air conditioning system is located;

[0046] A control module connected to the zone selection module to control the opening of the fresh air valve, the opening of the return air valve and the start and stop of the variable frequency outdoor unit of the air conditioning system; and the control module is preset with a first load reduction logic, a second load reduction logic, a first loading logic and a second loading logic;

[0047] A temperature acquisition module is connected to the PID operation module to acquire the current indoor temperature once at a preset time interval and feed the current indoor temperature back to the PID operation module;

[0048] A PID operation module connected to the control module to perform a logic operation based on the difference between the preset temperature and the current indoor temperature, thereby calculating the current demand of a single variable frequency outdoor unit and feeding back to the control module;

[0049] Among them, the control module executes any one of the first load reduction logic, the second load reduction logic, the first loading logic and the second loading logic according to the area type, the current total demand of the air-conditioning system and the initial start-up number n of the variable frequency outdoor unit, so as to meet the corresponding execution conditions.

[0050] Compared with the prior art, the present invention has the following technical effects:

[0051] (1) According to the preset first load reduction logic, second load reduction logic, first loading logic and second loading logic, the variable frequency outdoor units in different areas are controlled to increase or decrease loads, so as to avoid the variable frequency outdoor units working under extreme working conditions and ensure the long-term stable operation of the air-conditioning system.

[0052] (2) It solves the problem of low temperature control accuracy and large fluctuations, making the air-conditioning system more adaptable and more fault-tolerant.

[0053] (3) Through the built-in regional judgment logic, automatic matching of the area can be achieved without manual judgment, which improves the convenience of use. In addition, the air conditioning system can also switch the area type according to the operating conditions to ensure that it can continue to operate in the best operating state. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A flow chart of a regional temperature control method based on the requirements of a variable frequency outdoor unit provided in the first embodiment of the present invention;

[0055] Figure 2 This is a logic operation principle diagram of a single variable frequency external machine in the first embodiment of the present invention;

[0056] Figure 3 This is a flow chart of the area determination logic in the second embodiment of the present invention;

[0057] Figure 4 A structural diagram of a regional temperature control system based on the requirements of a variable frequency outdoor unit provided in the third embodiment of the present invention;

[0058] Figure 5 A structural diagram of a regional temperature control system based on the requirements of a variable frequency outdoor unit provided in the fourth embodiment of the present invention. DETAILED DESCRIPTION

[0059] The technical content of the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0060] In air conditioning systems in different places, it is necessary to control the air conditioning according to the actual conditions of the application places. In various embodiments of the present invention, the areas where the air conditioning system is located are divided into theater auditorium areas, hospital shopping mall areas, and data room areas. Different areas have different requirements for fresh air volume and the amount of cold and heat required to reach the target temperature, so the control logic for each area is different. In addition, the air conditioning system in this embodiment is composed of an indoor unit and multiple variable frequency outdoor units.

[0061] First embodiment

[0062] The first embodiment of the present invention provides a regional temperature control method based on the demand of the variable frequency outdoor unit, which controls the opening of the fresh air valve, the opening of the return air valve and the initial opening number of the variable frequency outdoor unit of the air conditioning system according to different regional types. In addition, the current demand of a single variable frequency outdoor unit is calculated in combination with logical operations, so that the variable frequency outdoor units in different regions are controlled to increase or decrease loads according to the preset first load reduction logic, second load reduction logic, first loading logic and second loading logic, so as to avoid the variable frequency outdoor unit working under extreme working conditions and ensure the long-term stable operation of the air conditioning system.

[0063] It is understandable that the user can judge and divide different area types by himself, and then directly click the corresponding control button on the air conditioning system according to the determined area type. In this way, the air conditioning system will start the control logic corresponding to the area type, thereby realizing precise control of the area.

[0064] Combine the following Figure 1 and Figure 2 , the regional temperature control method provided by the first embodiment of the present invention is described in detail:

[0065] 1. Theater Auditorium Area

[0066] The air conditioning system in this area is mainly a fresh air system. Due to the large number of people, more ventilation is required, and the required cooling and heating capacity is also relatively large. When the equipment is first started, the fresh air valve needs to be closed and the return air valve fully opened to quickly increase (when heating) or reduce (when cooling) the indoor temperature. The outdoor units are all started according to demand, and the target temperature is quickly reached after the start-up. Then the fresh air valve is opened, the return air valve is closed, and the outdoor unit outputs the appropriate frequency according to demand.

[0067] Specifically, the temperature control method of this area includes the following steps:

[0068] S1: The air conditioning system starts, controls the fresh air valve to be closed (i.e., the fresh air valve opening is 0), the return air valve to be fully opened (i.e., the return air valve opening is 100%), controls all the variable frequency outdoor units to be started (i.e., the initial number of variable frequency outdoor units turned on, n, is equal to the total number of variable frequency outdoor units, n is a positive integer) and runs at full load, so as to quickly approach the target temperature.

[0069] S2: Obtain the current indoor temperature of the area where the air-conditioning system is located, and perform a logical operation (preferably a PID control algorithm, but not limited to this, an MPC control algorithm or a fuzzy control algorithm may also be used) based on the difference between the preset temperature and the current indoor temperature to calculate the current demand of a single variable frequency outdoor unit.

[0070] Specifically, Figure 2 As shown in the figure, the current demand of a single variable frequency outdoor unit is calculated by the following formula:

[0071] u(k)=Kp e(k)+Ki ∑[e(0)…e(k-1)]+Kd [e(k)…e(k-1)]

[0072] Among them, u(k) represents the current demand calculated by a single variable frequency outdoor unit for the kth time; Kp represents the proportional coefficient, Ki represents the integral coefficient, Kd represents the differential coefficient, and Kp, Ki and Kd are preset according to different area types; e(k) represents the difference between the current indoor temperature sampled for the kth time and the preset temperature; k = 0, 1, 2, 3..., represents the sampling sequence number.

[0073] S3: Based on the current demand u(k) of a single variable frequency outdoor unit and the total number m of variable frequency outdoor units, calculate the current total demand u(k) of the air conditioning system. 总 ; where u(k) 总 =m u(k).

[0074] S4: Based on the current total demand u(k) of the air conditioning system 总As well as the initial number n of variable frequency outdoor units turned on, the preset first load reduction logic is executed to gradually reduce the load of the variable frequency outdoor units with the longest running time until all the variable frequency outdoor units are turned off.

[0075] In this embodiment, since all variable frequency outdoor machines are started in the initial state, n=m. Specifically, step S4 includes the following sub-steps:

[0076] S41: Calculate the expected total demand of n variable frequency outdoor units according to the initial start-up number n of the variable frequency outdoor units.

[0077] Each variable frequency outdoor machine is preset with the same expected demand. In this embodiment, the expected demand is in the form of a demand percentage, and based on historical experience, the expected demand is set to 40%. In other embodiments, it can also be set to other demand percentages as needed. Therefore, according to the initial start-up number n of the variable frequency outdoor machine, the expected total demand can be calculated as n. 40%.

[0078] In one embodiment of the present invention, for example, the total number m of variable frequency external machines is 8, then when n=m, the expected total demand is 8 40%=320%.

[0079] S42: updating the current total demand of the air conditioning system at every preset time interval.

[0080] Specifically, the current indoor temperature of the area where the air-conditioning system is located is collected once at a preset time interval, and a logical operation is performed based on the difference between the preset temperature and the current indoor temperature to update the current demand of a single variable frequency outdoor unit, and then update the current total demand of the air-conditioning system.

[0081] It is understandable that as the air-conditioning system continues to operate, the current indoor temperature will gradually approach the preset temperature. Accordingly, the current demand for a single variable frequency outdoor unit will gradually decrease, thereby gradually reducing the current total demand for the air-conditioning system.

[0082] S43: Judgment of supply and demand of current total demand.

[0083] When the current total demand of the air-conditioning system is updated, it is determined whether the current total demand of the air-conditioning system is less than the expected total demand of n-1 variable frequency outdoor units. If it is less, the load of the variable frequency outdoor unit with the longest running time is reduced; if it is not less, the n variable frequency outdoor units are kept running at full load until the current total demand of the air-conditioning system is less than the expected total demand of n-1 variable frequency outdoor units.

[0084] Specifically, we still take n=m=8 as an example. The initial expected total demand is 8 40%=320%. At this time, the 8 variable-frequency outdoor units continue to run at full load, which causes the current indoor temperature to continue to decrease. As the current indoor temperature continues to decrease, the current demand for a single variable-frequency outdoor unit after logical operation will decrease. Therefore, the current total demand for the 8 variable-frequency outdoor units will gradually decrease.

[0085] When the total current demand of the 8 variable frequency outdoor units is reduced to (n-1) When 40%=below 280%, it means that only 7 variable frequency outdoor units are needed to provide the expected demand to meet the current total demand. At this time, if 8 variable frequency outdoor units are still turned on, it will lead to a waste of resources. Therefore, the load of the variable frequency outdoor unit with the longest running time is reduced, so that the total number of variable frequency outdoor units changes from 8 to 7.

[0086] S44: Repeat the above process S41 to S43 until all variable frequency outdoor units are turned off.

[0087] It can be understood that when S41 to S43 are repeatedly executed for the first time, n in step S41 has become 7; when S41 to S43 are repeatedly executed for the second time, n in step S41 becomes 6; and so on, until all variable frequency outdoor units are completely turned off.

[0088] Specifically, if the current total demand is less than 280%, and if eight variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded;

[0089] The current total demand is less than 240%. If 7 variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded;

[0090] The current total demand is less than 200%. If six variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded.

[0091] The current total demand is less than 160%. If five variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded.

[0092] The current total demand is less than 120%. If four variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded.

[0093] The current total demand is less than 80%. If three variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded;

[0094] The current total demand is less than 40%. If two variable frequency outdoor units have been turned on, the variable frequency outdoor unit with the longest running time will be unloaded.

[0095] If the current total demand is ≤0, the currently turned-on variable frequency outdoor unit will be turned off.

[0096] In addition, in this embodiment, when the number of variable frequency outdoor units increases or decreases, the cooling output is allocated to each variable frequency outdoor unit according to the current number of variable frequency outdoor units and the current total demand of the air conditioning system, so that the cooling outputs of the variable frequency outdoor units are equal. In this way, it is possible to effectively avoid the variable frequency outdoor units from operating under extreme conditions (some operating at the maximum frequency and some operating at a lower frequency), thereby ensuring the long-term stable operation of the air conditioning system.

[0097] 2. Hospital shopping mall area

[0098] This type of area requires a large amount of fresh air, and the fresh air valve cannot be closed. Therefore, unlike the control method of the auditorium and theater, the fresh air valve is opened at 70% and the return air valve is opened at 30%. The supply air temperature is greatly affected by the outside temperature. The air conditioning system calculates the demand based on the set temperature and the current temperature, and calculates the demand and gives it to the outdoor unit control board. The outdoor unit control board performs energy regulation based on the received demand.

[0099] Specifically, the temperature control method of this area includes the following steps:

[0100] S10: The air conditioning system starts, controls the fresh air valve to open 70%, the return air valve to open 30%, and the variable frequency outdoor units are started first according to the total number of outdoor units m÷2 (rounded up). After the startup is completed, it lasts for a preset time (for example: 300S by default).

[0101] S20: Obtain the current indoor temperature of the area where the air conditioning system is located, and perform a logical operation based on the difference between the preset temperature and the current indoor temperature to calculate the current demand of a single variable frequency outdoor unit. This step has the same principle as the above step S2 and will not be repeated here.

[0102] S30: According to the current demand of a single variable frequency outdoor unit, the preset first loading logic or second load reduction logic is executed to gradually load the variable frequency outdoor unit or the variable frequency outdoor unit with the longest load reduction operation time until all the variable frequency outdoor units are shut down.

[0103] Specifically, step S30 includes the following sub-steps:

[0104] S301: After n variable frequency outdoor units have been running for a preset time, the current indoor temperature of the area where the air conditioning system is located is collected, and a logical operation is performed based on the difference between the preset temperature and the current indoor temperature to update the current demand of a single variable frequency outdoor unit.

[0105] S302: Determine whether the current demand of the updated single variable frequency outdoor machine is less than a preset load reduction threshold.

[0106] In this embodiment, the preset load reduction threshold is set to 100% according to the demand percentage. If the current demand of the updated single variable frequency outdoor machine is ≥ 100%, one variable frequency outdoor machine is loaded.

[0107] For example: initially, n=8 / 2=4. When the current demand of a single variable frequency outdoor unit is calculated to be ≥100%, the number of variable frequency outdoor units becomes n+1=5.

[0108] S303: updating the current demand of the single variable frequency outdoor machine again based on the n+1 variable frequency outdoor machines until the updated current demand of the single variable frequency outdoor machine is less than the preset load reduction threshold.

[0109] Specifically, as the number of variable frequency outdoor machines increases, the current demand for a single variable frequency outdoor machine will gradually decrease. When the current demand for a single variable frequency outdoor machine is less than 100%, the loading of the variable frequency outdoor machine is stopped, and step S304 is executed.

[0110] S304: Execute the second load reduction logic.

[0111] Specifically, if the current demand of a single variable frequency outdoor machine after the update is less than the preset load reduction threshold, all variable frequency outdoor machines under the current quantity are synchronously reduced in frequency. When all variable frequency outdoor machines are synchronously reduced in frequency to the lower limit frequency and continue to run for more than the second preset time (for example: 60s), the variable frequency outdoor machine with the longest running time is reduced in load.

[0112] If there is still a need to reduce load after the load reduction lasts for 60 seconds, then shut down another variable frequency outdoor unit with the longest running time, and so on, until the last variable frequency outdoor unit is shut down.

[0113] (III) Data center area

[0114] The fresh air demand in this area is very small, mainly for return air, and the temperature needs to be guaranteed. Specifically, the temperature control method for this area includes the following steps:

[0115] S100: The air conditioning system starts, controls the fresh air valve to open 20%, the return air valve to open 80%, and the variable frequency outdoor unit is not started temporarily (i.e. the initial opening quantity n=0).

[0116] S200: Obtain the current indoor temperature of the area where the air conditioning system is located, and perform a logical operation based on the difference between the preset temperature and the current indoor temperature to calculate the current demand of a single variable frequency outdoor unit. This step has the same principle as the above step S2 and will not be repeated here.

[0117] S300: Based on the current demand u(k) of a single variable frequency outdoor unit and the total number m of variable frequency outdoor units, calculate the current total demand u(k) of the air conditioning system. 总 ; where u(k) 总 =m u(k).

[0118] S400: According to the current total demand of the air-conditioning system and the initial number n of variable frequency outdoor units turned on, the second loading logic or the first load reduction logic is executed to gradually load the variable frequency outdoor units or the variable frequency outdoor units with the longest load reduction operation time until all the variable frequency outdoor units are turned off.

[0119] Specifically, step S400 includes the following sub-steps:

[0120] S401: Execute the second loading logic

[0121] Specifically, multiple preset loading thresholds are arranged in ascending order. In this embodiment, the multiple preset loading thresholds are 40%, 80%, 120%, 160%, 200%, 240%, 280% and 320%, corresponding to 8 variable frequency external units. It is understandable that in other embodiments, other loading thresholds can be set according to requirements.

[0122] Then, the current total demand of the air-conditioning system is compared with each preset loading threshold in turn. If the current total demand of the air-conditioning system is not less than the preset loading threshold currently compared, a variable frequency outdoor unit is loaded; otherwise, loading is stopped.

[0123] Specifically, when the current total demand is ≥40%, one variable frequency outdoor unit is started;

[0124] When the current total demand is ≥80%, start two variable frequency outdoor units;

[0125] When the current total demand is ≥120%, start 3 variable frequency outdoor units;

[0126] When the current total demand is ≥160%, start 4 variable frequency outdoor units;

[0127] When the current total demand is ≥200%, start 5 variable frequency outdoor units;

[0128] When the current total demand is ≥240%, start 6 variable frequency outdoor units;

[0129] When the current total demand is ≥280%, start 7 variable frequency outdoor units;

[0130] When the current total demand is ≥320%, start 8 variable frequency outdoor units.

[0131] S402: Execute the first load reduction logic according to the current demand of the single variable frequency outdoor machine.

[0132] It is understandable that as the variable frequency outdoor unit is continuously started, the current indoor temperature will gradually approach the set temperature, thereby gradually reducing the current total demand, and then the variable frequency outdoor unit can be unloaded according to the decrease in the current total demand.

[0133] Specifically, if the current total demand is less than 280%, if 8 variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded;

[0134] The current total demand is less than 240%. If 7 variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded;

[0135] The current total demand is less than 200%. If six variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded.

[0136] The current total demand is less than 160%. If five variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded.

[0137] The current total demand is less than 120%. If four variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded.

[0138] The current total demand is less than 80%. If three variable frequency outdoor units have been turned on, then the variable frequency outdoor unit with the longest running time will be unloaded;

[0139] The current total demand is less than 40%. If two variable frequency outdoor units have been turned on, the variable frequency outdoor unit with the longest running time will be unloaded.

[0140] If the current total demand is ≤0, the currently turned-on variable frequency outdoor unit will be turned off.

[0141] In summary, the first embodiment of the present invention provides a regional temperature control method based on the demand of the variable frequency outdoor unit. Different control logics can be configured according to the different areas where the air-conditioning system is located, so that the air-conditioning system can run stably with small fluctuations; and each control scheme is simple and efficient with high control accuracy.

[0142] Second embodiment

[0143] Based on the above-mentioned first embodiment, the second embodiment of the present invention provides another regional temperature control method based on the requirements of the variable frequency outdoor unit. Compared with the first embodiment, the difference of this embodiment is that the air-conditioning system has regional judgment logic and can automatically judge the regional type.

[0144] Specifically, Figure 3 As shown, the region determination logic in this embodiment is as follows:

[0145] ① The air conditioning system is put into trial operation, the fresh air valve is closed and the return air valve is opened, and the corresponding number of variable frequency outdoor units (4 in this embodiment) are started according to half of the total number, and the duration is preset (for example: 5-10 minutes).

[0146] ② During the trial operation of the air-conditioning system, the corresponding detection data is obtained based on the CO2 sensor pre-installed in the unit.

[0147] In this embodiment, there are 9 CO2 sensors evenly distributed in the unit, and each CO2 sensor has a preset normal data (about 500ppm). During the idle commissioning operation, each CO2 sensor obtains a corresponding detection data, so as to obtain the final detection data by averaging.

[0148] ③ According to the detection data and normal data of the CO2 sensor, obtain the data change trend of the CO2 sensor.

[0149] The data change trend can be judged by the difference between the detection data and the normal data of the CO2 sensor. Specifically, if the difference between the two is small, the data change trend is no obvious change; if the difference between the two is large and the detection data is much larger than the normal data, the data change trend is a rapid increase in value; if the difference between the two is average and the detection data is larger than the normal data, the data change trend is a slow increase in value.

[0150] For example, the normal data of the CO2 sensor is set to 500ppm in advance. If the detection data of the CO2 sensor is around 500ppm during the trial operation, it means there is no obvious change; if the detection data rises rapidly to 1000ppm or above, it means the value rises rapidly; if the detection data is around 750ppm, it means the value rises slowly.

[0151] ④ According to the data change trend of the CO2 sensor, obtain the area type of the area where the air conditioning system is located.

[0152] Specifically, when the data change trend is no obvious change, the area is judged to be a data room area; when the data change trend is a rapid increase in value, the area is judged to be a theater auditorium area; when the data change trend is a slow increase in value, the area is judged to be a hospital shopping mall area.

[0153] In addition, this embodiment also includes a region switching logic, which is as follows:

[0154] (1) After the air conditioning system has passed the regional judgment, it will continue to operate according to the control mode of the corresponding area, and will perform a regional judgment every preset time interval (for example: 2 hours).

[0155] (2) When the data change trend of the regional judgment shows no obvious change, the control mode corresponding to the original area is maintained and continues to operate; when the data change trend of the regional judgment shows a downward trend for two consecutive times and the decline reaches the preset level, it is switched to the control mode corresponding to the data room area.

[0156] In this embodiment, except for the above-mentioned area determination logic and area switching logic, other control logics are the same as those in the first embodiment and will not be described in detail herein.

[0157] Third embodiment

[0158] like Figure 4 As shown, based on the above first embodiment, the third embodiment of the present invention provides a regional temperature control system based on the demand of the variable frequency outdoor unit, including a regional selection module 1, a control module 2, a temperature acquisition module 3 and a PID operation module 4. Among them, the control module 2 is the core module of the system, which is used to control the opening of the fresh air valve, the opening of the return air valve and the start and stop of the variable frequency outdoor unit of the air conditioning system; and the control module 2 is preset with a first load reduction logic, a second load reduction logic, a first loading logic and a second loading logic.

[0159] Specifically, the area selection module 1 is used to obtain the area type of the area where the air conditioning system is located. In addition, the control module 2 is connected to the area selection module 1 to control the opening of the fresh air valve, the opening of the return air valve and the start and stop of the variable frequency outdoor unit of the air conditioning system according to different area types.

[0160] The temperature acquisition module 3 is connected to the PID operation module 4 to collect the current indoor temperature once every preset time interval, and feed back the current indoor temperature to the PID operation module 4. Accordingly, the PID operation module 4 performs a logical operation based on the difference between the preset temperature and the current indoor temperature, thereby calculating the current demand of a single variable frequency outdoor unit. In addition, the PID operation module 4 is also connected to the control module 2 to feed back the current demand of a single variable frequency outdoor unit to the control module 2. It should be noted that the PID operation module 4 can be replaced by an MPC operation module that executes an MPC control algorithm or a fuzzy operation module that executes a fuzzy control algorithm.

[0161] Therefore, the control module 2 executes one of the first load reduction logic, the second load reduction logic, the first loading logic and the second loading logic according to the area type, the current total demand of the air-conditioning system and the initial number n of variable frequency outdoor units turned on, so as to meet the corresponding execution conditions.

[0162] Fourth embodiment

[0163] like Figure 5 As shown, based on the above first embodiment, the fourth embodiment of the present invention provides a regional temperature control system based on the requirements of the variable frequency outdoor unit. The regional temperature control system includes one or more processors 21 and a memory 22. The memory 22 is coupled to the processor 21 and is used to store one or more programs. When the one or more programs are executed by the one or more processors 21, the one or more processors 21 implement the regional temperature control method as in the above embodiment.

[0164] The processor 21 is used to control the overall operation of the sub-regional temperature control system to complete all or part of the steps of the above-mentioned sub-regional temperature control method. The processor 21 can be a central processing unit (CPU), a graphics processing unit (GPU), a field programmable gate array (FPGA), an application-specific integrated circuit (ASIC), a digital signal processing (DSP) chip, etc. The memory 22 is used to store various types of data to support the operation of the sub-regional temperature control system, and these data may include, for example, instructions for any application or method for operating on the sub-regional temperature control system, and application-related data. The memory 22 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as a static random access memory (SRAM), an electrically erasable programmable read-only memory (EEPROM), an erasable programmable read-only memory (EPROM), a programmable read-only memory (PROM), a read-only memory (ROM), a magnetic memory, a flash memory, etc.

[0165] In an exemplary embodiment, the sub-region temperature control system can be implemented by a computer chip or entity, or by a product with a certain function, for executing the above-mentioned sub-region temperature control method and achieving the same technical effect as the above-mentioned method. A typical embodiment is a computer. Specifically, the computer can be, for example, a personal computer, a laptop computer, a vehicle-mounted human-computer interaction device, a cellular phone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0166] In another exemplary embodiment, the present invention further provides a computer-readable storage medium including program instructions, which, when executed by a processor, implements the steps of the regional temperature control method in any of the above embodiments. For example, the computer-readable storage medium may be the above-mentioned memory including program instructions, and the above-mentioned program instructions may be executed by a processor of a regional temperature control system to complete the above-mentioned regional temperature control method and achieve the technical effect consistent with the above-mentioned method.

[0167] In summary, the regional temperature control method and system based on the requirements of the variable frequency outdoor unit provided by the embodiment of the present invention have the following beneficial effects:

[0168] (1) According to the preset first load reduction logic, second load reduction logic, first loading logic and second loading logic, the variable frequency outdoor units in different areas are controlled to increase or decrease loads, so as to avoid the variable frequency outdoor units working under extreme working conditions and ensure the long-term stable operation of the air-conditioning system.

[0169] (2) It solves the problem of low temperature control accuracy and large fluctuations, making the air-conditioning system more adaptable and more fault-tolerant.

[0170] (3) Through the built-in regional judgment logic, automatic matching of the area can be achieved without manual judgment, which improves the convenience of use. In addition, the air conditioning system can also switch the area type according to the operating conditions to ensure that it can continue to operate in the best operating state.

[0171] It should be noted that the above embodiments are only examples, and the technical solutions of the various embodiments can be combined, all within the protection scope of the present invention.

[0172] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0173] The above is a detailed description of the regional temperature control method and system based on the variable frequency outdoor unit requirements provided by the present invention. For those skilled in the art, any obvious changes made to it without departing from the essence of the present invention will constitute an infringement of the patent right of the present invention and will bear the corresponding legal liability.

Claims

1. A regional temperature control method based on the requirements of variable frequency outdoor units, characterized in that The steps include: Obtain the area type of the area where the air-conditioning system is located; wherein the air-conditioning system is composed of an indoor unit and multiple variable-frequency outdoor units; the area type includes at least a theater auditorium area, a hospital shopping mall area or a data room area; specifically includes: during the trial operation of the air-conditioning system, the fresh air valve is closed and the return air valve is opened, and a corresponding number of variable-frequency outdoor units are started according to half of the total number, for a preset duration; during the trial operation of the air-conditioning system, corresponding detection data is obtained based on a CO2 sensor pre-set in the unit; wherein the CO2 sensor has pre-set normal data; based on the detection data and normal data of the CO2 sensor, the data change trend of the CO2 sensor is obtained; based on the data change trend of the CO2 sensor, the area type of the area where the air-conditioning system is located is obtained; wherein, when the data change trend is no obvious change, the area is judged to be a data room area; when the data change trend is a rapid increase in value, the area is judged to be a theater auditorium area; when the data change trend is a slow increase in value, the area is judged to be a hospital shopping mall area; According to the zone type, the opening of the fresh air valve and the opening of the return air valve of the air conditioning system, as well as the initial opening number n of the variable frequency outdoor unit are controlled; wherein the opening of the fresh air valve, the opening of the return air valve and the initial opening number n of the variable frequency outdoor unit corresponding to different zone types are all different, and n is a positive integer; Obtaining the current indoor temperature of the area where the air conditioning system is located, and performing a logical operation based on the difference between the preset temperature and the current indoor temperature to calculate the current demand of a single variable frequency outdoor unit; Calculating the total current demand of the air conditioning system based on the current demand of the single variable frequency outdoor unit and the total number of the variable frequency outdoor units; In the theater auditorium area, according to the current total demand of the air-conditioning system and the initial number of the variable frequency outdoor units turned on, the preset first load reduction logic is executed to gradually reduce the load of the variable frequency outdoor unit with the longest running time until all the variable frequency outdoor units are completely shut down; in the hospital shopping mall area, according to the current demand of the single variable frequency outdoor unit, the preset first loading logic or the second load reduction logic is executed to gradually load the variable frequency outdoor unit or the variable frequency outdoor unit with the longest load reduction running time until all the variable frequency outdoor units are completely shut down; in the data room area, according to the current total demand of the air-conditioning system and the initial number n of the variable frequency outdoor units turned on, the second loading logic or the first load reduction logic is executed to gradually load the variable frequency outdoor unit or the variable frequency outdoor unit with the longest load reduction running time until all the variable frequency outdoor units are completely shut down.

2. The regional temperature control method according to claim 1, characterized in that: After the air conditioning system has been judged by a region, it will continue to operate according to the control mode of the corresponding region, and will perform a region judgment at a preset interval thereafter; when the data change trend of the region judgment is no obvious change, the control mode corresponding to the original region will be maintained for continuous operation; When the data change trends of two consecutive regional judgments are both downward and the decline reaches a preset level, switch to the control mode corresponding to the data room area.

3. The regional temperature control method according to claim 1, characterized in that The first load reduction logic specifically includes: According to the initial start-up number n of the variable frequency outdoor machines, the expected total demand of n variable frequency outdoor machines is calculated; wherein each of the variable frequency outdoor machines is preset with the same expected demand; The current indoor temperature of the area where the air-conditioning system is located is collected once at a preset time interval, and a logical operation is performed based on the difference between the preset temperature and the current indoor temperature to update the current demand of a single variable frequency outdoor unit, and then update the current total demand of the air-conditioning system; Determining whether the current total demand of the air-conditioning system is less than the expected total demand of n-1 variable frequency outdoor units; If it is less than, then reduce the load of the variable frequency outdoor unit with the longest running time; if it is not less than, then keep n variable frequency outdoor units running at full load until the current total demand of the air-conditioning system is less than the expected total demand of n-1 variable frequency outdoor units; Repeat the above process until all variable frequency outdoor units are turned off.

4. The regional temperature control method according to claim 1, characterized in that The first loading logic specifically includes: After n of the variable frequency outdoor units have been running for a preset time, the current indoor temperature of the area where the air conditioning system is located is collected, and a logical operation is performed based on the difference between the preset temperature and the current indoor temperature to update the current demand of a single variable frequency outdoor unit; Determine whether the current demand of the updated single variable frequency outdoor unit is less than the preset load reduction threshold; If it is less than, stop loading the variable frequency external machine and execute the second load reduction logic; if it is not less than, load a variable frequency external machine, and update the current demand of the single variable frequency external machine again based on n+1 variable frequency external machines, until the updated current demand of the single variable frequency external machine is less than the preset load reduction threshold.

5. The regional temperature control method according to claim 4, characterized in that The second load reduction logic specifically includes: If the current demand of a single variable-frequency outdoor unit after the update is less than the preset load reduction threshold, all variable-frequency outdoor units under the current quantity will be synchronously reduced in frequency; When all the variable frequency outdoor units are synchronously reduced to the lower frequency limit and continue to run for more than the second preset time, the load of the variable frequency outdoor unit with the longest running time is reduced.

6. The regional temperature control method according to claim 1, characterized in that The second loading logic specifically includes: Arrange multiple preset loading thresholds in ascending order; According to the arrangement order of the plurality of preset loading thresholds, sequentially comparing the current total demand of the air conditioning system with the size of each preset loading threshold; If the current total demand of the air-conditioning system is not less than the preset loading threshold value of the current comparison, one variable frequency outdoor unit is loaded; otherwise, the loading is stopped.

7. The regional temperature control method according to claim 1, characterized in that: In the theater auditorium area, the opening of the fresh air valve is 0, the opening of the return air valve is 100%, and the initial opening number n of the variable frequency outdoor units is the total number of variable frequency outdoor units; In the hospital shopping mall area, the opening of the fresh air valve is 70%, the opening of the return air valve is 30%, and the initial opening number n of the variable frequency outdoor units is half of the total number of variable frequency outdoor units; in the data room area, the opening of the fresh air valve is 20%, the opening of the return air valve is 80%, and the initial opening number n of the variable frequency outdoor units is 0.

8. A regional temperature control system, used to implement the regional temperature control method according to any one of claims 1 to 7, characterized in that include: A region selection module is used to obtain the region type of the region where the air conditioning system is located; A control module connected to the zone selection module to control the opening of the fresh air valve, the opening of the return air valve and the start and stop of the variable frequency outdoor unit of the air conditioning system; and the control module is preset with a first load reduction logic, a second load reduction logic, a first loading logic and a second loading logic; A temperature acquisition module is connected to the PID operation module to acquire the current indoor temperature once at a preset time interval and feed the current indoor temperature back to the PID operation module; A PID operation module connected to the control module to perform a logic operation based on the difference between the preset temperature and the current indoor temperature, thereby calculating the current demand of a single variable frequency outdoor unit and feeding back to the control module; Among them, the control module executes any one of the first load reduction logic, the second load reduction logic, the first loading logic and the second loading logic according to the area type, the current total demand of the air-conditioning system and the initial start-up number n of the variable frequency outdoor unit, so as to meet the corresponding execution conditions.

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