Unit operation strategy diagnosis method and device and water chilling unit

Abstract

The invention discloses a unit operation strategy diagnosis method and device and a water chilling unit. The method comprises the steps that a plurality of unit combinations are determined according to the total number k of the water chilling units; wherein the unit combination comprises any one unit,... any (k-1) units and k units; the efficient cooling capacity interval of each unit combination is determined; the unit operation strategy qualified rate of each efficient cooling capacity interval in one time period is calculated, and the final unit operation strategy qualified rate is obtained; and executing a corresponding diagnosis strategy according to the qualified rate of the final unit operation strategy. Through the method, the unit operation strategy qualification rate is determined according to the efficient cooling capacity intervals of different unit combinations in combination with the actual unit operation condition duration proportion condition, and unit operation diagnosis opinions are correspondingly output. Therefore, continuous rationalization of unit operation strategies and high-efficiency operation are ensured, and high-efficiency operation of the system is realized. And the conditions of unreasonable control of the number of the water chilling units, low-efficiency operation of the water chilling units and the like are avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of chillers, and in particular to a chiller operation strategy diagnosis method and device. Background Art

[0002] The continuous high efficiency and energy saving of central air-conditioning systems has become the goal of the current HVAC industry. It is a consensus to achieve the integrated high efficiency and energy saving operation of chillers, water pumps, cooling towers and other equipment throughout the year. This not only puts high demands on system design and equipment performance, but also brings difficulties to the operation energy management mode. With the development of Internet big data, the energy management of air-conditioning systems has evolved from automation to optimization management. As the core power output, the efficient and reasonable operation control strategy of chillers can achieve 15% to 40% energy saving in the system. Therefore, it is very important to diagnose and manage the efficient operation strategy of chillers. However, there is currently no more effective solution for the diagnosis and management of the efficient operation strategy of chillers. Existing chillers have problems such as unreasonable control of the number of units and inefficient operation of chillers.

[0003] With regard to the problem that there is no more effective diagnostic scheme for efficient operation strategy of chillers in the prior art, no effective solution has been proposed yet. Summary of the invention

[0004] The embodiments of the present invention provide a unit operation strategy diagnosis method, device and chiller to solve the problem that there is no more effective chiller high-efficiency operation strategy diagnosis solution in the prior art.

[0005] To solve the above technical problems, the present invention provides a unit operation strategy diagnosis method, wherein the method comprises: determining multiple unit combinations according to the total number k of units of the chiller; wherein the unit combinations include: any 1 unit, ... any k-1 units, k units; k is a non-zero natural number; determining the high-efficiency cooling capacity interval of each unit combination; calculating the unit operation strategy qualification rate of each high-efficiency cooling capacity interval within a time period to obtain the final unit operation strategy qualification rate; and executing the corresponding diagnostic strategy according to the final unit operation strategy qualification rate.

[0006] Furthermore, determining the efficient cooling capacity interval of each unit combination includes: obtaining the chilled water supply temperature and the cooling return water temperature during the operation of each unit combination; and determining the efficient cooling capacity interval according to the chilled water supply temperature and the cooling return water temperature.

[0007] Furthermore, the qualification rate of the unit operation strategy for each high-efficiency cooling capacity interval within a time period is calculated, including: determining the optimal unit combination corresponding to each high-efficiency cooling capacity interval; calculating the operating time of the optimal unit combination in its high-efficiency cooling capacity interval within a time period, and the proportion of the total operating time of all unit combinations in the high-efficiency cooling capacity interval to obtain the qualification rate of the unit operation strategy for the high-efficiency cooling capacity interval.

[0008] Furthermore, the optimal unit combination corresponding to each high-efficiency cooling capacity interval is determined, including: determining a reasonable cooling capacity interval for each unit combination; determining a system load rate interval based on the reasonable cooling capacity interval; generating a load rate-energy efficiency ratio curve for each unit combination based on the system load rate interval and system energy efficiency corresponding to each unit combination; and according to the load rate-energy efficiency ratio curve for each unit combination, confirming the unit combination with the highest system energy efficiency at the same system load rate within each high-efficiency cooling capacity interval, and determining it as the optimal unit combination.

[0009] Furthermore, determining a reasonable cooling capacity range for each unit combination includes: obtaining unit selection information, and determining the cooling capacity of each unit according to the unit selection information; determining that a reasonable cooling capacity range for each unit combination is: [a%*cooling capacity of the unit combination, b%*cooling capacity of the unit combination]; wherein a% and b% are preset ratio values.

[0010] Furthermore, before determining the reasonable cooling capacity interval of each unit combination, the method also includes: obtaining the building load and wet-bulb temperature distribution; determining the cooling capacity range within a time period according to the building load and wet-bulb temperature distribution; wherein the reasonable cooling capacity interval of each unit combination is within the cooling capacity range.

[0011] Furthermore, obtaining the final unit operation strategy qualification rate includes: averaging the unit operation strategy qualification rates of all high-efficiency cooling capacity intervals within a time period to obtain the final unit operation strategy qualification rate.

[0012] Furthermore, executing a corresponding diagnostic strategy according to the final unit operation strategy qualification rate includes:

[0013] If the final unit operation strategy qualification rate>m, it is determined that the diagnostic strategy is to check for equipment abnormalities;

[0014] If n≤the final unit operation strategy qualification rate≤m, then determining that the diagnosis strategy is an operation strategy for optimizing the unit combination;

[0015] If the final unit operation strategy qualification rate is less than n, it is determined that the diagnosis strategy is a reasonable unit operation strategy, and the unit continues to operate efficiently.

[0016] Furthermore, the operation strategy of the unit combination is optimized, including: determining the high-efficiency cooling capacity interval corresponding to the unit operation strategy qualification rate that is lower than a preset qualification rate threshold; and taking the unit combination in an inefficient operation state within the high-efficiency cooling capacity interval as the unit combination to be optimized.

[0017] Further, if the final unit operation strategy qualification rate is less than n, it is determined that the diagnosis strategy is a reasonable unit operation strategy, and the unit continues to operate efficiently, including: if the final unit operation strategy qualification rate is less than n, further confirming whether the unit operation strategy qualification rate of each high-efficiency cooling capacity interval exceeds a preset value; if so, it is determined that the diagnosis strategy is a reasonable unit operation strategy, and the unit continues to operate efficiently; if not, optimizing the unit combination that is in an inefficient operating state within the high-efficiency cooling capacity interval corresponding to the unit operation strategy qualification rate that does not exceed the preset value.

[0018] The present invention also provides a unit operation strategy diagnosis device, wherein the device includes: a first processing module, used to determine multiple unit combinations according to the total number k of units of the chiller; wherein the unit combination includes: any 1 unit,...any k-1 units, k units; k is a non-zero natural number; a second processing module, used to determine the high-efficiency cooling capacity interval of each unit combination; a calculation module, used to calculate the unit operation strategy qualification rate of each high-efficiency cooling capacity interval within a time period to obtain the final unit operation strategy qualification rate; a diagnosis module, used to execute the corresponding diagnosis strategy according to the final unit operation strategy qualification rate.

[0019] The present invention also provides a chiller, wherein the chiller includes the above-mentioned chiller operation strategy diagnosis device.

[0020] The present invention also provides a computer-readable storage medium having a computer program stored thereon, wherein the program implements the above method when executed by a processor.

[0021] Different combinations of chillers have different operating effects, resulting in large differences in system energy efficiency. The technical solution of the present invention is applied to determine the qualified rate of the unit operation strategy according to the high-efficiency cooling capacity range of different unit combinations and the actual operating condition duration of the unit, and output the unit operation diagnosis opinions accordingly. This ensures that the unit operation strategy is continuously rationalized and the operation is efficient, and the system can be operated efficiently. Avoid situations such as unreasonable control of the number of chillers and inefficient operation of chillers. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a flow chart of a method for diagnosing a unit operation strategy according to an embodiment of the present invention;

[0023] Figure 2is a schematic diagram of a load rate-energy efficiency ratio curve according to an embodiment of the present invention;

[0024] Figure 3 is an example diagram of a high-efficiency strategy for unit operation according to an embodiment of the present invention;

[0025] Figure 4 is a block diagram of the diagnostic idea of ​​the high-efficiency strategy of unit operation according to an embodiment of the present invention;

[0026] Figure 5 is a schematic diagram of cooling load-hours in a spring transition month according to an embodiment of the present invention;

[0027] Figure 6 is a schematic diagram of cooling load-hours in a high temperature month according to an embodiment of the present invention;

[0028] Figure 7 is a schematic diagram of cooling load-hours in the autumn transition month according to an embodiment of the present invention;

[0029] Figure 8 is a flowchart of outputting diagnostic opinions according to an embodiment of the present invention;

[0030] Fig. 9 4 is a structural block diagram of a unit operation strategy diagnosis device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0033] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0034] As used herein, the words "if" and "if" may be interpreted as "at the time of" or "when" or "in response to determining" or "in response to detecting", depending on the context. Similarly, the phrases "if it is determined" or "if (stated condition or event) is detected" may be interpreted as "when it is determined" or "in response to determining" or "when detecting (stated condition or event)" or "in response to detecting (stated condition or event)", depending on the context.

[0035] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0036] The optional embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0037] Example 1

[0038] Different combinations of chillers have different operating effects, resulting in large differences in system energy efficiency. Therefore, monitoring the relevant data of the unit operation strategy, collecting statistics on the unit operation strategy and conducting diagnostic analysis are of great significance to ensure the efficient operation of the refrigeration room system.

[0039] According to an embodiment of the present invention, a method embodiment of unit operation strategy diagnosis is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0040] Figure 1 is a flow chart of a method for diagnosing a unit operation strategy according to an embodiment of the present invention. Figure 1 As shown, the method comprises the following steps:

[0041] Step S101, determining a plurality of unit combinations according to the total number k of units of the chiller; wherein the unit combinations include: any 1 unit, ... any k-1 units, k units; k is a non-zero natural number;

[0042] Step S102, determining the efficient cooling capacity range of each unit combination;

[0043] Step S103, calculating the qualified rate of the unit operation strategy in each high-efficiency cooling capacity interval within a time period, and obtaining the final qualified rate of the unit operation strategy;

[0044] Step S104, executing the corresponding diagnosis strategy according to the final unit operation strategy qualification rate.

[0045] When determining the unit combination, this embodiment determines all possible unit combinations based on the total number of units k. Assuming k=3, that is, the system has 3 units, then there are 6 possible unit combinations. The reason for counting all possible unit combinations is to calculate the unit operation strategy qualification rate, so as to determine the diagnosis strategy, optimize the unit combination matching plan, and realize the efficient operation of the system.

[0046] After determining all the unit combinations that the system can achieve, determine the efficient cooling capacity interval of each unit combination, and the efficient cooling capacity interval is used to calculate the qualification rate of the subsequent computer group operation strategy. As for how to determine the efficient cooling capacity interval of each unit combination, a full-condition performance curve is set when the unit is factory-set, based on which the efficient cooling capacity interval of each unit combination can be obtained. During the operation of different unit combinations, the chilled water supply temperature and the cooling return water temperature during the operation of each unit combination can be obtained; the efficient cooling capacity interval is determined based on the chilled water supply temperature and the cooling return water temperature. That is, the efficient cooling capacity interval of each unit combination is initially determined according to the factory setting information. In specific implementation, the relevant data of the chilled water supply temperature and the cooling return water temperature are obtained, and the cooling return water temperature interval is divided according to the interval of △t1, and the chilled water supply temperature interval is divided according to the interval of △t2. The corresponding efficient cooling capacity interval can be output in combination with the above cooling return water temperature interval and the above chilled water supply temperature interval. Based on this, the corresponding high-efficiency cooling capacity range can be obtained more accurately according to the operating conditions of different unit combinations. The high-efficiency cooling capacity range of each unit combination is the key data for the subsequent computer group operation strategy qualification rate.

[0047] After determining the efficient cooling capacity interval of each unit combination, the unit operation strategy qualification rate of each efficient cooling capacity interval within a time period is calculated to obtain the final unit operation strategy qualification rate. A time period of this embodiment can be set to one year, or it can be set according to actual operation requirements. The specific calculation scheme is as follows: determine the optimal unit combination corresponding to each efficient cooling capacity interval; calculate the operating time of the optimal unit combination in its efficient cooling capacity interval within a time period, and the proportion of the total operating time of all unit combinations in the efficient cooling capacity interval to obtain the unit operation strategy qualification rate of the efficient cooling capacity interval. The above-mentioned implementation method uses the actual operating conditions (operating time) of the unit combination as the key data for calculating the computer unit operation strategy qualification rate, which can reflect the operating effect of different combinations of chillers, so that the data that can characterize the system operation effect can be quickly, efficiently and accurately calculated: the unit operation strategy qualification rate.

[0048] It should be noted that in different high-efficiency cooling capacity intervals, there will be one or more unit combinations operating in the high-efficiency cooling capacity interval. When different unit combinations operate in the high-efficiency cooling capacity interval, the system energy efficiency that can be achieved is different. The highest system energy efficiency indicates that it is the optimal unit combination. Based on this, this embodiment provides a preferred implementation method, that is, determining the optimal unit combination corresponding to each high-efficiency cooling capacity interval, including: determining a reasonable cooling capacity interval for each unit combination; determining a system load rate interval based on the reasonable cooling capacity interval; generating a load rate-energy efficiency ratio curve for each unit combination based on the system load rate interval and system energy efficiency corresponding to each unit combination; according to the load rate-energy efficiency ratio curve of each unit combination, confirming the unit combination with the highest system energy efficiency at the same system load rate in each high-efficiency cooling capacity interval, and determining it as the optimal unit combination. Based on this, the optimal unit combination in each high-efficiency cooling capacity interval can be accurately identified based on the key parameter of system energy efficiency. Provide a reference basis for the unit operation matching method, thereby effectively improving the system operation energy efficiency.

[0049] Figure 2 is a schematic diagram of a load rate-energy efficiency ratio curve according to an embodiment of the present invention, such as Figure 2 As shown, the X-axis is the system load rate (%), and the Y-axis is the system energy efficiency ratio (EER). The system energy efficiency ratio (EER) is the ratio of the total cooling capacity of the refrigeration room to the total power consumption of the room equipment (unit + water pump + cooling tower), which reflects the energy-saving level of the system.

[0050] Considering the need to determine the reasonable cooling capacity interval of each unit combination, in order to ensure the accuracy of the cooling capacity interval setting, before determining the reasonable cooling capacity interval of each unit combination, the unit selection information is obtained, and the cooling capacity of each unit is determined according to the unit selection information. The reasonable cooling capacity interval of each unit combination is determined as: [a%*cooling capacity of unit combination, b%*cooling capacity of unit combination]; where a% and b% are preset ratio values. Conventional group control a% can be set to 30%, and b% can be set to 90%. During the stage of each unit's exit setting, its model, cooling capacity, power and other information will be marked in its selection information. Based on this, a more reasonable cooling capacity range of each unit combination can be determined, and the unit combination will operate within the above reasonable cooling capacity range under normal conditions. The reasonable cooling capacity interval and high-efficiency cooling capacity interval corresponding to different unit combinations can be determined more accurately according to the cooling capacity information of each unit, thereby improving the accuracy of the cooling capacity interval setting.

[0051] After determining the reasonable cooling capacity range of each unit combination: [a%*cooling capacity of unit combination, b%*cooling capacity of unit combination], determine the system load rate range based on the reasonable cooling capacity range. Specifically: [a%*cooling capacity of unit combination / total cooling capacity of system, b%*cooling capacity of unit combination / total cooling capacity of system] is the system load rate range. Figure 2As shown, each curve represents the load factor-energy efficiency ratio curve of each unit combination.

[0052] Figure 3 is an example diagram of a high-efficiency strategy for unit operation according to an embodiment of the present invention, such as Figure 3 As shown in the figure, a system including two 950RT and two 1900RT units is used as an example for schematic illustration. The unit combinations of the system include: 950RT×1, 1900RT×1, 950RT×1+1900RT×1, 1900RT×2, 950RT×1+1900RT×2, 950RT×2+1900RT×2. Figure 2 Observe the load rate-energy efficiency ratio curve. Figure 3 Only the above 6 unit combinations are taken as examples for illustration, and other combinations are not shown for the time being. Figure 2 The curves from left to right in the figure are the load rate-energy efficiency ratio curves of the above six combinations. Figure 2 The leftmost curve is the load rate-energy efficiency ratio curve of the unit combination of 950RT×1, and the rightmost curve is the load rate-energy efficiency ratio curve of the unit combination of 950RT×2+1900RT×2.

[0053] Figure 2 In addition to displaying the load factor-energy efficiency ratio curve of each unit combination, Figure 2 It can be seen that the system load rate range corresponds to the efficient cooling capacity range of each unit combination. Figure 2 In the equation, the intersection of two adjacent load factor-energy efficiency ratio curves is the end point of the system load factor range. If two adjacent load factor-energy efficiency ratio curves do not intersect directly, for example, the load factor-energy efficiency ratio curve of 950RT×1 and the load factor-energy efficiency ratio curve of 1900RT×1 do not intersect directly, then determine the system load factor on the X-axis corresponding to the end point of the previous curve, and the point corresponding to the system load factor in the latter curve is used as the intersection point of the two curves. Figure 3 The load range shown is the endpoint of the system load rate range determined based on the intersection of two adjacent load rate-energy efficiency ratio curves, so as to obtain the system load rate range corresponding to the high-efficiency cooling capacity range, such as 0-3340, 3340-6379, 6379-9653, 9653-11890, 11890-15364, 15364-20040. Figure 3The values ​​in the table represent the operating hours of the unit combination. For example, 93 represents the operating hours of the unit combination 1900RT×2 in the system load rate range of 3340 to 6379. The qualified rate of the unit operation strategy in each system load rate range can be calculated based on the operating hours. Since there is a definite conversion relationship between the high-efficiency cooling capacity range and the system load rate range, and the two are in a one-to-one correspondence, the qualified rate of the unit operation strategy in each high-efficiency cooling capacity range can be determined.

[0054] As mentioned above, based on the load rate-energy efficiency ratio curve of each unit combination, the unit combination with the highest system energy efficiency at the same system load rate in each high-efficiency cooling capacity range is determined as the optimal unit combination. Figure 3 In the same system load rate range, the unit combination with the curve at the top is the optimal unit combination.

[0055] This embodiment also takes into account that the reasonable cooling capacity interval of each unit combination needs to be within the entire cooling capacity range of the system. To ensure this, this embodiment provides a preferred implementation method, that is, before determining the reasonable cooling capacity interval of each unit combination, obtain the building load and wet-bulb temperature distribution; determine the cooling capacity range within a time period according to the building load and wet-bulb temperature distribution; wherein the reasonable cooling capacity interval of each unit combination is within the cooling capacity range. This ensures that the unit operation strategy diagnosis scheme of this embodiment is reasonable and ensures the safe and stable operation of the system.

[0056] Figure 3 The table also shows the qualified rate of unit operation strategies in all high-efficiency cooling capacity intervals. For example, the qualified rate of unit operation strategies corresponding to the load interval of 3340-6379 is t1%. For 0-3340, no unit combination operates in this load interval, which is not included in the calculation of the final qualified rate of unit operation strategies. Finally, the average of t1%, t2%, and t3% is taken to obtain the final qualified rate of unit operation strategies, t%.

[0057] After calculating the qualified rates of the unit operation strategies in all high-efficiency cooling capacity intervals, the qualified rates of the unit operation strategies in all high-efficiency cooling capacity intervals within a time period are averaged to obtain the final qualified rate of the unit operation strategy. Based on this, the final data reflecting the effect of the unit combination scheme can be obtained: the final qualified rate of the unit operation strategy, which can characterize whether the unit combination scheme during system operation is efficient and whether it needs to be improved and optimized. According to this data, the corresponding diagnostic strategy can be executed.

[0058] Specifically, the corresponding diagnostic strategy is executed according to the final unit operation strategy qualification rate, including:

[0059] (1) If the final unit operation strategy qualification rate is greater than m, the diagnostic strategy is determined to be to check for equipment abnormalities.

[0060] When the final unit operation strategy qualification rate is greater than m, it is considered that there are some problems with the actual group control strategy of the system or that there are abnormalities in the equipment. It is recommended to check whether there are abnormalities in the system and equipment. The specific unit operation problems can be checked according to the unreasonable cumulative time proportion limit of the group combination. It is recommended to prioritize the low-efficiency units to check whether there are equipment problems such as dirty evaporators and condensers, refrigerant leakage, and excessive wear of compressor parts. After ensuring that there are no problems with the chiller itself, check the system operation problems to see whether there are control system failures or improper settings, such as abnormal operation of the thermostat and pressure controller, improper load matching, manual control or automatic control abnormalities, and other system problems.

[0061] (2) If n≤final unit operation strategy qualification rate≤m, it is determined that the diagnosis strategy is the operation strategy for optimizing the unit combination.

[0062] When n≤final unit operation strategy qualification rate≤m, there may be deviations in the control strategy that need to be optimized, and the control strategy can be optimized. According to the unreasonable time proportion limit of different sub-combinations, check the operation problems under the corresponding unit combination, including the above equipment abnormalities or system problems.

[0063] The operation strategy of optimizing the unit combination can be realized by the following preferred implementation: determining the high-efficiency cooling capacity interval corresponding to the unit operation strategy qualification rate that is lower than the preset qualification rate threshold; and taking the unit combination in the high-efficiency cooling capacity interval that is in an inefficient operation state as the unit combination to be optimized. Based on this, the unit combination to be optimized can be accurately and quickly identified and locked, indicating that the combination mode of the unit combination to be optimized is not efficient enough and needs to be adjusted.

[0064] (3) If the final unit operation strategy qualification rate is less than n, it is determined that the diagnosis strategy is a reasonable unit operation strategy, and the unit continues to operate efficiently.

[0065] When the final unit operation strategy qualification rate is less than n, the system operation strategy is considered reasonable. Alternatively, when the final unit operation strategy qualification rate is less than n, and the unit operation strategy qualification rates of all high-efficiency cooling capacity intervals exceed the preset value, the system operation strategy is considered reasonable.

[0066] Combined with the real-time energy efficiency display of the system, if the energy efficiency range is normal, the system can maintain the efficient operation of the operation strategy and save it to the cloud database to provide reference for data analysis and AI intelligent control. If the accumulated unreasonable time proportion of some combinations is not within a reasonable range, the system still has the potential for regulation and efficiency improvement. If the system operation is relatively reasonable, but the overall energy efficiency of the entire system is low, the corresponding unit equipment should be checked for equipment problems such as dirty evaporators and condensers, refrigerant leakage, and excessive wear of compressor components based on the deviation between the unit design energy efficiency and the actual operation energy efficiency.

[0067] In the above preferred implementation, the corresponding diagnostic strategy is executed according to the final unit operation strategy qualification rate, and the unit response can be quickly made according to the final unit operation strategy qualification rate, and the optimization strategy can be determined to more comprehensively ensure the efficient operation of the system.

[0068] This embodiment determines the unit operation strategy qualification rate and outputs the unit operation diagnosis opinion based on the reasonable cooling capacity range and efficient cooling capacity range of different unit combinations and the actual operating condition hourly data proportion of the unit. This ensures that the unit operation strategy is continuously rationalized and the operation is efficient, and the system is efficiently operated. It solves the problems of unreasonable control of the number of chillers and inefficient operation of chillers.

[0069] This embodiment formulates a unit operation high-efficiency interval control strategy table according to different chilled water temperatures and high-frequency segments of cooling water temperature, and determines the unit operation strategy qualification rate based on the proportion of hourly data of actual operating conditions of the unit, and performs diagnostic analysis.

[0070] This embodiment provides a chiller efficient operation strategy diagnosis scheme. For engineering types with stable building loads, based on the cold load distribution trend, wet-bulb temperature frequency and other influencing factors, the complete chiller model library data is used to determine the high frequency segments of cooling water temperature under different freezing water temperatures, formulate a unit operation efficient interval control strategy table, and combine the actual unit operating condition hourly data proportion to determine the unit operation strategy qualification rate, and output the unit operation diagnosis opinion. This embodiment can analyze and diagnose the unit situation in real time, output unit operation optimization suggestions, and solve the problems of unreasonable control of the number of chillers and inefficient operation of chillers in existing projects.

[0071] Example 2

[0072] Figure 4 is a block diagram of the diagnostic idea of ​​the high-efficiency strategy of the unit operation according to an embodiment of the present invention, such as Figure 4 As shown, this embodiment introduces a high-efficiency operation strategy diagnosis scheme for chillers. For engineering types with stable building loads, based on the cold load distribution trend, wet-bulb temperature frequency and other influencing factors, the complete chiller model library data is used to determine the high-frequency segments of cooling water temperature under different freezing water temperatures, formulate a high-efficiency interval control strategy table for the unit operation, and determine the qualified rate of the unit operation strategy in combination with the actual operating condition hourly data proportion of the unit, and output the unit operation diagnosis opinion. The unit operation high-efficiency strategy diagnosis idea of ​​this embodiment mainly includes 4 parts, namely, determining the unit load, wet-bulb temperature distribution range, judging the unit joint operation interval, calculating the qualified rate of the unit operation strategy according to the unit operation time proportion, and outputting the diagnosis opinion.

[0073] The first step is the unit load and wet bulb temperature distribution range.

[0074] According to the building load and wet-bulb temperature distribution statistics of actual project operation, it is found that the building load and wet-bulb temperature show the same fluctuation trend (positive correlation). Therefore, this embodiment is aimed at the project type with stable building load (i.e., the building type with little fluctuation in the number of internal personnel and activities, such as office buildings, factories, etc.), and highly combines the building load and wet-bulb temperature. For example, the cooling season can be divided into three regions in the time dimension, including spring transition month, high temperature month, and autumn transition month. Figure 5 The schematic diagram of cooling load-hours in the spring transition month is shown in Figure 6 The cooling load-hour diagram for the hot month is shown in Figure 7 The schematic diagram of cooling load-hours in the autumn transition month is shown. Different regions and climate zones should be divided according to the cooling time. Taking Guangdong Province as an example, the spring transition months in the wet-bulb temperature concentration area include April to May at [19,23]℃, the high temperature months are June to September at [24,27]℃, and the autumn transition months are October to November at [21,24]℃. On the above basis, there is a positive correlation between wet-bulb temperature and load, that is, the temperature rises and the load increases. Through the wet-bulb temperature and load distribution, the cooling demand and temperature range of the project in different months can be determined, and then the optimal number of units and operating conditions can be matched.

[0075] The second step is to determine the joint operation range of the units.

[0076] Arrange and combine the units according to the total number of units in the system. Take the selection of a certain factory as an example. The system includes 2 units of 3340kW* and 2 units of 6680kW*. According to the rated cooling / heating capacity of the units, they are sorted from small to large, and the system (number), unit type, and unit model of the units are listed. The "√" method is used to determine the unit operation matching situation as shown in Table 1.

[0077] Table 1

[0078]

[0079]

[0080] The third step is to calculate the pass rate of the computer group operation strategy according to the proportion of unit operation time.

[0081] After the unit operation control strategy is determined, the unit cooling water temperature operating temperature concentration range is determined according to the unit wet bulb temperature distribution in different monthly segments, and then the reasonable cooling capacity range and high-efficiency cooling capacity range of the unit combination are determined based on the complete unit performance database.

[0082] Reasonable cooling capacity range: According to the conventional group control 30% / 90% addition and subtraction of machines, the reasonable range of combined operation cooling capacity is calculated. This has been described in detail above.

[0083] High-efficiency cooling capacity interval: According to the different chilled water supply temperatures and cooling return water temperatures obtained, the cooling return water temperature interval is divided according to the △t1 interval, the chilled water supply temperature interval is divided according to the △t2 interval, and the high-efficiency cooling capacity interval is output.

[0084] The corresponding system load rate range can be calculated based on the reasonable cooling capacity range / high-efficiency cooling capacity range. The principle is: Q = b*Qz;

[0085] Where: Q is the cooling capacity (kW), Q cannot be greater than the total installed capacity of the chiller under the current unit combination, b is the system load rate (%), Qz is the total installed capacity of the system (kW), that is, the sum of the cooling capacity of all chillers.

[0086] Figure 3 This is a table of high-efficiency unit operation strategies using a factory as an example. The first row of the table is the load range, and the first column of the table is the unit owner combination, which is combined according to the actual project selection and follows the basic group control strategy. The numbers in the table are the operating hours of the unit combination, the shaded part is the hours the unit runs in the high-efficiency cooling range, and the blank area is the hours the unit runs in the reasonable cooling range.

[0087] Determine the optimal unit combination corresponding to each high-efficiency cooling capacity interval; calculate the operating time of the optimal unit combination in its high-efficiency cooling capacity interval within a time period, and the proportion of the total operating time of all unit combinations in this high-efficiency cooling capacity interval to obtain the unit operation strategy qualification rate in this high-efficiency cooling capacity interval.

[0088] The operation strategy table can be built into the group control PLC for statistics, and updated and iterated regularly according to the actual operation situation to ensure the system maintenance effect.

[0089] The fourth step is to output diagnostic opinions.

[0090] Figure 8 is a flow chart of outputting diagnostic opinions according to an embodiment of the present invention. Figure 8 As shown, the following steps are included:

[0091] Step S801, calculate the unit operation strategy qualification rate of each high-efficiency cooling capacity interval within a time period to obtain the final unit operation strategy qualification rate.

[0092] Step S802: If the final unit operation strategy qualification rate>m, it is determined that the diagnosis strategy is to check for equipment abnormalities.

[0093] When the final unit operation strategy qualification rate is greater than m, it is considered that there are some problems with the actual group control strategy of the system or that there are abnormalities in the equipment. It is recommended to check whether there are abnormalities in the system and equipment. The specific unit operation problems can be checked according to the unreasonable cumulative time proportion limit of the group combination. It is recommended to prioritize the low-efficiency units to check whether there are equipment problems such as dirty evaporators and condensers, refrigerant leakage, and excessive wear of compressor parts. After ensuring that there are no problems with the chiller itself, check the system operation problems to see whether there are control system failures or improper settings, such as abnormal operation of the thermostat and pressure controller, improper load matching, manual control or automatic control abnormalities, and other system problems.

[0094] Step S803: if n≤final unit operation strategy qualification rate≤m, it is determined that the diagnosis strategy is an operation strategy for optimizing the unit combination.

[0095] When n≤final unit operation strategy qualification rate≤m, there may be deviations in the control strategy that need to be optimized, and the control strategy can be optimized. According to the unreasonable time proportion limit of different sub-combinations, check the operation problems under the corresponding unit combination, including the above equipment abnormalities or system problems.

[0096] The operation strategy of optimizing the unit combination can be realized by the following preferred implementation: determining the high-efficiency cooling capacity interval corresponding to the unit operation strategy qualification rate that is lower than the preset qualification rate threshold; and taking the unit combination in the high-efficiency cooling capacity interval that is in an inefficient operation state as the unit combination to be optimized. Based on this, the unit combination to be optimized can be accurately and quickly identified and locked, indicating that the combination mode of the unit combination to be optimized is not efficient enough and needs to be adjusted.

[0097] Step S804, if the final unit operation strategy qualification rate is less than n, the diagnosis strategy is determined to be a reasonable unit operation strategy, the unit continues to operate efficiently, the unit operation strategy is recorded, and the system operation in the next time period (eg, next year) is guided.

[0098] When the final unit operation strategy qualification rate is less than n, the system operation strategy is considered reasonable. Alternatively, when the final unit operation strategy qualification rate is less than n, and the unit operation strategy qualification rates of all high-efficiency cooling capacity intervals exceed the preset value, the system operation strategy is considered reasonable.

[0099] Combined with the real-time energy efficiency display of the system, if the energy efficiency range is normal, the system can maintain the efficient operation of the operation strategy and save it to the cloud database to provide reference for data analysis and AI intelligent control. If the accumulated unreasonable time proportion of some combinations is not within a reasonable range, the system still has the potential for regulation and efficiency improvement. If the system operation is relatively reasonable, but the overall energy efficiency of the entire system is low, the corresponding unit equipment should be checked for equipment problems such as dirty evaporators and condensers, refrigerant leakage, and excessive wear of compressor components based on the deviation between the unit design energy efficiency and the actual operation energy efficiency.

[0100] This embodiment can also be applied to the selection of new project solutions, the selection of optimized operation control strategies, and the diagnosis and analysis of chiller operation strategies for actual operating engineering projects. It can analyze and output unit operation optimization suggestions in real time, and solve problems such as unreasonable control of the number of chillers and inefficient operation of chillers in existing projects.

[0101] Example 3

[0102] Corresponds to Figure 1 The unit operation strategy diagnosis method described in the present embodiment provides a unit operation strategy diagnosis device, such as Fig. 9 The structural block diagram of the unit operation strategy diagnostic device shown in FIG. 1 includes:

[0103] The first processing module 10 is used to determine a plurality of unit combinations according to the total number k of units of the chiller; wherein the unit combination includes: any 1 unit, ... any k-1 units, k units; k is a non-zero natural number;

[0104] The second processing module 20 is used to determine the efficient cooling capacity range of each unit combination;

[0105] The calculation module 30 is used to calculate the qualified rate of the unit operation strategy in each high-efficiency cooling capacity interval within a time period to obtain the final qualified rate of the unit operation strategy;

[0106] The diagnosis module 40 is used to execute the corresponding diagnosis strategy according to the final unit operation strategy qualification rate.

[0107] The unit operation strategy diagnosis device of this embodiment can implement the unit operation strategy diagnosis scheme introduced above, determine the unit operation strategy qualification rate according to the high-efficiency cooling capacity interval of different unit combinations and the actual operating condition duration of the unit, and output the unit operation diagnosis opinions accordingly. This ensures that the unit operation strategy is continuously rationalized and the operation is efficient, and realizes efficient operation of the system. It avoids the occurrence of unreasonable control of the number of chillers and inefficient operation of chillers.

[0108] This embodiment also provides a chiller, wherein the chiller includes the chiller operation strategy diagnosis device introduced above.

[0109] Example 4

[0110] The embodiment of the present invention provides a software, which is used to execute the technical solutions described in the above embodiment and preferred implementation manner.

[0111] An embodiment of the present invention provides a non-volatile computer storage medium, wherein the computer storage medium stores computer executable instructions, and the computer executable instructions can execute a method in any of the above method embodiments.

[0112] The above-mentioned software is stored in the above-mentioned storage medium, which includes but is not limited to: a CD, a floppy disk, a hard disk, an erasable memory, etc.

[0113] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0114] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0115] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0116] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0117] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0118] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0119] The above product can execute the method provided by the embodiment of the present invention, and has the functional modules and beneficial effects corresponding to the execution method. For technical details not described in detail in this embodiment, please refer to the method provided by the embodiment of the present invention.

[0120] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0121] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A unit operation strategy diagnosis method, characterized in that: The method comprises: Determine multiple unit combinations according to the total number k of units of the chiller; wherein the unit combinations include: any 1 unit, ... any k-1 units, k units; k is a non-zero natural number; Determine the efficient cooling capacity range of each unit combination; Calculate the qualified rate of the unit operation strategy in each high-efficiency cooling capacity interval within a time period to obtain the final qualified rate of the unit operation strategy; The corresponding diagnosis strategy is executed according to the final unit operation strategy qualification rate.

2. The method according to claim 1, characterized in that Determine the efficient cooling capacity range of each unit combination, including: Obtain the chilled water supply temperature and cooling water return temperature during the combined operation of each unit; The efficient cooling capacity range is determined according to the chilled water supply temperature and the cooling water return temperature.

3. The method according to claim 1, characterized in that Calculate the qualified rate of unit operation strategy in each high-efficiency cooling capacity interval within a time period, including: Determine the optimal unit combination corresponding to each high-efficiency cooling capacity range; Calculate the operating time of the optimal unit combination in its high-efficiency cooling capacity range within a time period and the proportion of the total operating time of all unit combinations in this high-efficiency cooling capacity range to obtain the qualified rate of the unit operation strategy in this high-efficiency cooling capacity range.

4. The method according to claim 3, characterized in that Determine the optimal unit combination corresponding to each high-efficiency cooling capacity range, including: Determine the reasonable cooling capacity range of each unit combination; Determine the system load rate range according to the reasonable cooling capacity range; Generate a load rate-energy efficiency ratio curve for each unit combination according to the system load rate range and system energy efficiency corresponding to each unit combination; According to the load rate-energy efficiency ratio curve of each unit combination, the unit combination with the highest system energy efficiency at the same system load rate in each high-efficiency cooling capacity range is identified and determined as the optimal unit combination.

5. The method according to claim 4, characterized in that Determine the reasonable cooling capacity range for each unit combination, including: Acquire unit selection information, and determine the cooling capacity of each unit according to the unit selection information; The reasonable cooling capacity range of each unit combination is determined as: [a%*cooling capacity of the unit combination, b%*cooling capacity of the unit combination]; wherein a% and b% are preset ratio values.

6. The method according to claim 4, characterized in that Before determining the reasonable cooling capacity range of each unit combination, the method further includes: Obtain building load and wet bulb temperature distribution; The cooling capacity range within a time period is determined according to the building load and wet-bulb temperature distribution; wherein the reasonable cooling capacity interval of each unit combination is within the cooling capacity range.

7. The method according to claim 1, characterized in that The final unit operation strategy qualification rate is obtained, including: The average of the unit operation strategy qualification rates of all high-efficiency cooling capacity intervals within a time period is calculated to obtain the final unit operation strategy qualification rate.

8. The method according to claim 1, characterized in that Executing corresponding diagnostic strategies according to the final unit operation strategy qualification rate includes: If the final unit operation strategy qualification rate>m, it is determined that the diagnostic strategy is to check for equipment abnormalities; If n≤the final unit operation strategy qualification rate≤m, then determining that the diagnosis strategy is an operation strategy for optimizing the unit combination; If the final unit operation strategy qualification rate is less than n, it is determined that the diagnosis strategy is a reasonable unit operation strategy, and the unit continues to operate efficiently.

9. The method according to claim 8, characterized in that Optimize the operation strategy of unit combination, including: Determine the high-efficiency cooling capacity range corresponding to the unit operation strategy qualification rate that is lower than the preset qualification rate threshold; The unit combination in the high-efficiency cooling capacity range and in an inefficient operating state is taken as the unit combination to be optimized.

10. The method according to claim 8, characterized in that If the final unit operation strategy qualification rate is less than n, it is determined that the diagnosis strategy is a reasonable unit operation strategy, and the unit continues to operate efficiently, including: If the final unit operation strategy qualification rate is less than n, further confirm whether the unit operation strategy qualification rate of each high-efficiency cooling capacity interval exceeds a preset value; If yes, determine that the diagnostic strategy is a reasonable unit operation strategy and continue to maintain efficient unit operation; If not, then the combination of units in an inefficient operating state within the high-efficiency cooling capacity range corresponding to the unit operation strategy qualification rate that does not exceed the preset value is optimized.

11. A unit operation strategy diagnostic device, characterized in that: The device comprises: The first processing module is used to determine a plurality of unit combinations according to the total number k of units of the chiller; wherein the unit combinations include: any 1 unit, ... any k-1 units, k units; k is a non-zero natural number; The second processing module is used to determine the efficient cooling capacity range of each unit combination; A calculation module is used to calculate the qualified rate of the unit operation strategy in each high-efficiency cooling capacity interval within a time period to obtain the final qualified rate of the unit operation strategy; The diagnosis module is used to execute the corresponding diagnosis strategy according to the final unit operation strategy qualification rate.

12. A chiller, characterized in that: The chiller includes the chiller operation strategy diagnostic device according to claim 11.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the method according to any one of claims 1 to 10 is implemented.

Images