Method and device for controlling a water chiller, water chiller, storage medium

Abstract

The application relates to the technical field of water chilling units, and discloses a method for controlling a water chilling unit, which comprises the following steps: in response to a start-up control instruction, determining a target number of compressors that need to be started according to the temperature difference between the initial water temperature of the water chilling unit and the set temperature; and starting the compressors according to the target number, wherein the compressors with short running time are preferentially started. In the case that the water chilling unit is started, the corresponding number of compressors are started based on the temperature difference between the initial water temperature and the set temperature, so that the compressors can be started according to the load demand of the current system, the situation that the temperature demand of a user cannot be met or energy is wasted is avoided, the user experience is improved, the compressors with short running time are preferentially started, the total running time of the compressors is balanced, the number of the compressors and the temperature regulation capacity are matched with the actual load demand of the system, and the service life of the water chilling unit is prolonged. The application further discloses a device for controlling a water chilling unit, a water chilling unit and a storage medium.

Description

Technical Field

[0001] This application relates to the field of chiller technology, for example to a method and apparatus for controlling a chiller, a chiller, and a storage medium. Background Technology

[0002] Currently, when chiller units adjust the operating status of their components to keep the chilled water outlet temperature constant within a set temperature range, the inlet and outlet water temperatures are both low when the actual load is small, which can easily lead to energy waste. Furthermore, due to the variability of user loads, controlling the chiller unit based solely on the deviation between the actual water temperature and the target water temperature often results in frequent loading and unloading of the chiller unit, or even continuous start-stop operations, leading to poor system stability and affecting the user experience.

[0003] The related technology discloses a highly efficient and stable control method for a magnetic levitation chiller unit. This method includes calculating the load based on the actual outlet water temperature, setting a target outlet water temperature, comparing the actual outlet water temperature with the target temperature, and combining the difference between the actual outlet water temperature and the target temperature with the start-up temperature difference or shutdown temperature difference to adjust the operating state of the chiller unit's compressor. The operating state of the chiller unit is divided into four types: loading the corresponding load per cycle, increasing the number of compressors, unloading the corresponding load per cycle, and reducing the number of compressors started. This improves the control accuracy of the chiller unit, reduces the frequency of compressor start-up and shutdown, and makes the system operation more stable and reliable.

[0004] In the process of implementing the embodiments of this disclosure, at least the following problems were found in the related art:

[0005] When a chiller unit is started, the user needs to actively select the compressor to run. However, the number of compressors and their temperature regulation capabilities selected by the user may not match the actual load requirements of the system. This can result in the chiller unit having a weak temperature regulation capability that fails to meet the user's temperature requirements, or the chiller unit having an excessively large temperature regulation capability that wastes energy. Summary of the Invention

[0006] To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or describe the scope of protection of these embodiments, but rather as a prelude to the detailed description that follows.

[0007] This disclosure provides a method and apparatus for controlling a chiller unit, a chiller unit, and a storage medium, so that when the chiller unit is turned on, the number of compressors and the temperature regulation capability are matched with the actual load demand of the system, thereby avoiding situations where user temperature requirements cannot be met or energy is wasted, and improving the user experience.

[0008] In some embodiments, the chiller unit includes multiple compressors; the method includes: in response to a start-up control command, determining a target number of compressors to be started based on the temperature difference between the initial water temperature and the set temperature of the chiller unit; and starting the compressors according to the target number, wherein compressors with shorter running times are started preferentially.

[0009] In some embodiments, the apparatus includes a processor and a memory storing program instructions, wherein the processor is configured to execute the method for controlling a chiller unit as described above when executing the program instructions.

[0010] In some embodiments, the chiller unit includes: a plurality of compressors; and the aforementioned device for controlling the chiller unit.

[0011] In some embodiments, the storage medium stores program instructions that, when executed, perform the aforementioned method for controlling a chiller unit.

[0012] The method and apparatus for controlling a chiller unit, the chiller unit itself, and the storage medium provided in this disclosure can achieve the following technical effects:

[0013] In response to the start-up control command, the system determines the target number of compressors to be started based on the temperature difference between the initial water temperature and the set temperature of the chiller unit. Based on this target number, the compressors are started, prioritizing those with shorter operating times. When the chiller unit is running, starting the corresponding number of compressors based on the temperature difference between the initial water temperature and the set temperature ensures that compressors are activated according to the current system load demand. This avoids situations where user temperature requirements cannot be met or energy is wasted, improving the user experience. Furthermore, prioritizing the activation of compressors with shorter operating times ensures that the total operating time of each compressor is balanced. This matches the number of compressors and their temperature regulation capacity with the actual system load demand, while extending the service life of the chiller unit.

[0014] The above general description and the description below are exemplary and illustrative only and are not intended to limit this application. Attached Figure Description

[0015] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations and drawings do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are shown as similar elements. The drawings are not to be scaled. And wherein:

[0016] Figure 1 This is a schematic diagram of a method for controlling a chiller unit provided in an embodiment of this disclosure;

[0017] Figure 2This is a schematic diagram of another method for controlling a chiller unit provided in an embodiment of this disclosure;

[0018] Figure 3 This is a schematic diagram of another method for controlling a chiller unit provided in an embodiment of this disclosure;

[0019] Figure 4 This is a schematic diagram of another method for controlling a chiller unit provided in an embodiment of this disclosure;

[0020] Figure 5 This is a schematic diagram of another method for controlling a chiller unit provided in an embodiment of this disclosure;

[0021] Figure 6 This is a schematic diagram of a device for controlling a chiller unit provided in an embodiment of this disclosure. Detailed Implementation

[0022] To provide a more detailed understanding of the features and technical content of the embodiments of this disclosure, the implementation of the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for illustrative purposes only and are not intended to limit the embodiments of this disclosure. In the following technical description, for ease of explanation, several details are used to provide a full understanding of the disclosed embodiments. However, one or more embodiments may still be implemented without these details. In other cases, well-known structures and devices may be simplified in their depiction to simplify the drawings.

[0023] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this disclosure described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0024] Unless otherwise stated, the term "multiple" means two or more.

[0025] In this embodiment of the disclosure, the character " / " indicates that the objects before and after it are in an "or" relationship. For example, A / B means: A or B.

[0026] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0027] The term "correspondence" can refer to an association or binding relationship. The correspondence between A and B means that there is an association or binding relationship between A and B.

[0028] This disclosure provides a chiller unit comprising multiple compressors. After the chiller unit is started, and after the chiller unit performs operations to increase or decrease the number of compressors, the number of operating compressors is always greater than or equal to a first number.

[0029] Based on the structure of the chiller unit described above, embodiments of this disclosure provide a method for controlling the chiller unit. For example... Figure 1 As shown, the method includes:

[0030] S01, the chiller unit responds to the start-up control command and determines the target number of compressors to be started based on the temperature difference between the initial water temperature and the set temperature of the chiller unit.

[0031] S02, the chiller unit starts the compressor according to the target number; among them, the compressor with the shortest running time is started first.

[0032] The method for controlling a chiller unit provided in this disclosure, in response to a start-up control command, determines the target number of compressors to be started based on the temperature difference between the initial water temperature and the set temperature of the chiller unit, and starts the compressors according to the target number, prioritizing the start of compressors with shorter operating times. When the chiller unit is started, starting the corresponding number of compressors based on the temperature difference between the initial water temperature and the set temperature allows for the compressors to be started according to the current system load demand, maximizing the compressors' temperature regulation capabilities to meet the system load requirements. This ensures that the number of compressors and their temperature regulation capabilities match the actual system load demand, avoiding situations where user temperature requirements cannot be met or energy is wasted, thus improving the user experience. Furthermore, prioritizing the start of compressors with shorter operating times ensures that the total operating time of each compressor is balanced, thereby extending the service life of the chiller unit while matching the number of compressors and their temperature regulation capabilities to the actual system load demand.

[0033] This disclosure provides a method for controlling a chiller unit. For example... Figure 2 As shown, the method includes:

[0034] S21, the chiller unit detects the outlet water temperature and determines the outlet water temperature as the initial water temperature.

[0035] S22, the start-up temperature difference between the initial water temperature and the set temperature of the chiller unit.

[0036] S23, the target quantity of the chiller unit is determined based on the start-up temperature difference.

[0037] S02, the chiller unit starts the compressor according to the target number; among them, the compressor with the shortest running time is started first.

[0038] The outlet water temperature can be replaced by the set temperature as the initial water temperature, because the temperature difference between the set temperature and the set temperature can also characterize the current state of the chiller unit. Furthermore, the inlet water temperature is directly related to the chiller unit's condensing temperature; all other things being equal, a higher inlet water temperature leads to higher condensing temperature and pressure, and consequently, higher energy consumption. Using the outlet water temperature as the initial water temperature takes into account the impact of condensing temperature and pressure on chiller unit operation, ensuring that the number of compressors matches the current system load requirements of the chiller unit, thus reducing energy consumption. Additionally, the average of the set and outlet water temperatures, or a characteristic temperature value calculated using other mathematical methods, can be used as the initial water temperature, allowing for more precise compressor startup.

[0039] The chiller unit control method provided in this disclosure detects the outlet water temperature and determines it as the initial water temperature. Since the outlet water temperature characterizes the current state of the chiller unit, calculating the start-up temperature difference between the initial water temperature and the set temperature allows for accurate determination of the load required by the chiller unit to bring the indoor temperature to the set point. Based on the start-up temperature difference, the chiller unit determines the target quantity, ensuring that the number of compressors matches the current system load required by the chiller unit, thereby enabling more precise start-up of the corresponding compressors.

[0040] This disclosure provides a method for controlling a chiller unit. For example... Figure 3 As shown, the method includes:

[0041] S21, the chiller unit detects the outlet water temperature and determines the outlet water temperature as the initial water temperature.

[0042] S22, the start-up temperature difference between the initial water temperature and the set temperature of the chiller unit.

[0043] S31, chiller unit calculation N=K×S×δT.

[0044] S02, the chiller unit starts the compressor according to the target number; among them, the compressor with the shortest running time is started first.

[0045] Where N is the target quantity, K is the compressor start-up coefficient related to the initial water temperature, S is the total number of compressors in the chiller unit, and δT is the start-up temperature difference. The compressor start-up coefficient is negatively correlated with the outlet water temperature. The initial water temperature can be the outlet water temperature, the inlet water temperature, or the average of the outlet water temperature and the inlet water temperature, or a characteristic temperature value calculated by other mathematical methods.

[0046] Using the chiller unit control method provided in this disclosure, the chiller unit calculates N = K × S × δT. Since the outlet water temperature of the chiller unit is directly related to the evaporation temperature, under the same conditions, the lower the outlet water temperature, the lower the evaporation temperature and evaporation pressure, resulting in increased energy consumption and reduced cooling capacity of the chiller unit. Therefore, in order to meet user temperature requirements while reducing energy consumption, a target quantity is calculated using a chiller head start-up coefficient associated with the outlet water temperature. This ensures that the target quantity matches the outlet water temperature, achieving a balance between the required cooling capacity and the chiller unit's energy consumption, thereby improving the efficiency of temperature regulation.

[0047] This disclosure provides a method for controlling a chiller unit. For example... Figure 4 As shown, the method includes:

[0048] S01, the chiller unit responds to the start-up control command and determines the target number of compressors to be started based on the temperature difference between the initial water temperature and the set temperature of the chiller unit.

[0049] S41, if the target number is greater than or equal to the first number, the chiller unit starts the compressor of the target number.

[0050] S42, if the target number is less than the first number, start the first number of compressors in the chiller unit.

[0051] Among these, compressors with shorter operating times are prioritized for startup. The first number is the minimum number of compressors that can be started without affecting the temperature control capability of the chiller unit.

[0052] Using the chiller unit control method provided in this disclosure, when the target number of chillers is greater than or equal to a first number, the number of compressors that need to be started is greater than or equal to the minimum number of compressors that need to be started. This does not affect the chiller unit's temperature control capability. Therefore, the chiller unit starts the target number of compressors to meet the system load requirements at startup. When the target number of chillers is less than the first number, the number of compressors that need to be started is less than the minimum number of compressors that need to be started, which may affect the chiller unit's temperature control capability. Therefore, the first number of compressors is started to avoid affecting the chiller unit's temperature control capability.

[0053] This disclosure provides a method for controlling a chiller unit. For example... Figure 5 As shown, the method includes:

[0054] S01, the chiller unit responds to the start-up control command and determines the target number of compressors to be started based on the temperature difference between the initial water temperature and the set temperature of the chiller unit.

[0055] S02, the chiller unit starts the compressor according to the target number; among them, the compressor with the shortest running time is started first.

[0056] S51: After a set time, the chiller unit will perform corresponding operations based on the rate of change of the chiller unit's water temperature.

[0057] The corresponding operations include loading the compressor, unloading the compressor, starting the compressor, or stopping the compressor. The water temperature change rate is the average of the water temperature change rates over a preset time period.

[0058] The method for controlling a chiller unit provided in this disclosure addresses the issue that when a chiller unit starts up, a target number of compressors are activated simultaneously, resulting in significant water temperature fluctuations. If the load reduction is not timely, the compressors may shut down due to reaching the stop temperature difference, leading to frequent compressor start-stops. Alternatively, starting the target number of compressors one by one can result in slow loading, failing to meet user temperature requirements and hindering the system from quickly establishing a pressure differential, thus triggering compressor failure. Therefore, after a set time following the activation of the set number of compressors, the chiller unit performs corresponding operations based on the chiller's water temperature change rate: loading the activated compressors, unloading the activated compressors, starting the compressors, or shutting them down. This timely loading or unloading of the compressors avoids frequent start-stops due to reaching the stop temperature difference and prevents the system from failing to establish a pressure differential in time, thus improving the stability of the chiller unit's operation.

[0059] Optionally, the chiller unit performs corresponding operations based on the water temperature change rate of the chiller unit, including: when the water temperature change rate is greater than a first threshold, the chiller unit performs a loading operation on the started compressor; when the water temperature change rate is greater than a second threshold, the chiller unit starts a second number of compressors; when the water temperature change rate is less than a third threshold, the chiller unit performs a unloading operation on the started compressors; when the water temperature change rate is less than a fourth threshold, the chiller unit shuts down a third number of compressors; wherein the second threshold is greater than the first threshold, the third threshold is greater than the fourth threshold, and the first threshold is greater than the third threshold.

[0060] Thus, when the water temperature change rate exceeds the first threshold, the water temperature rises rapidly. The current temperature control capacity of the started compressors cannot meet the system load demand after the water temperature rises. Therefore, a loading operation is performed on the started compressors to improve the chiller's temperature control capability. When the water temperature change rate exceeds the second threshold, the water temperature rises rapidly again. At this point, the upper limit of the temperature control capacity of the target number of compressors cannot meet the system load demand after the water temperature rises. Therefore, a second number of compressors are started to further improve the overall temperature control capability of the chiller. When the water temperature change rate is less than the third threshold, the water temperature drops rapidly, and the system load demand of the chiller decreases. Therefore, a load reduction operation is performed on the started compressors to prevent them from shutting down before reaching the stop temperature difference, thus affecting the operation of the chiller and matching the temperature control capability of the started compressors with the system load demand, thereby reducing energy consumption. When the water temperature change rate of the chiller unit is less than the fourth threshold, the water temperature drops too rapidly, and the system load demand decreases significantly. Therefore, the third number of compressors is shut down to prevent the compressors from failing to unload in time after the water temperature drops, causing them to shut down due to reaching the shutdown temperature difference, thus affecting the operation of the chiller unit and reducing the overall temperature regulation capacity of the chiller unit to reduce energy consumption. By monitoring the water temperature change rate, the chiller unit can proactively add or remove loads and compressor heads from already started compressors to avoid situations where the water temperature changes too rapidly due to excessive temperature differences and cannot be adjusted in time.

[0061] Optionally, the chiller unit performs corresponding operations based on the water temperature change rate of the chiller unit, and further includes: when the water temperature change rate of the chiller unit is less than or equal to a first threshold and greater than or equal to a third threshold, the chiller unit performs corresponding operations based on the temperature difference between the current water temperature and the set temperature of the chiller unit.

[0062] Thus, when the water temperature change rate is between the first and third thresholds, the water temperature rises and falls slowly, resulting in minimal temperature variation. However, when the water temperature change rate is low, the temperature difference between the current water temperature and the set temperature may be significant, potentially leading to a large compressor shutdown temperature difference. This could result in untimely load reduction, compressor shutdown affecting unit operation, or slow loading that fails to meet system load demands. Therefore, the chiller unit performs corresponding operations based on the temperature difference between the current water temperature and the set temperature to reduce the risk of untimely load increases / decreases or compressor head adjustments.

[0063] Optionally, the chiller unit performs corresponding operations based on the temperature difference between the current water temperature and the set temperature, including: increasing the load on the already started compressor when the temperature difference is non-negative and less than or equal to the first temperature difference; starting the compressor according to the fourth number when the temperature difference is non-negative and greater than the first temperature difference; reducing the load on the already started compressor when the temperature difference is negative and the absolute value of the temperature difference is less than or equal to the second temperature difference; and shutting down the compressor according to the fifth number when the temperature difference is negative and the absolute value of the temperature difference is greater than the first temperature difference.

[0064] The first temperature difference can be the difference between the second and first thresholds, and the second temperature difference can be the difference between the third and fourth thresholds. The magnitudes of the loading and unloading operations are smaller than those when the water temperature change rate is greater than the first and second thresholds, respectively. The fourth quantity is greater than the second quantity, and the fifth quantity is greater than the third quantity.

[0065] Thus, when the chiller unit has a non-negative temperature difference that is less than or equal to the first temperature difference, although the water temperature rises slowly, the current water temperature is higher than the set temperature, posing a relatively high risk of insufficient temperature regulation due to delayed loading. Therefore, a significant overload operation is performed on the compressors already running. When the chiller unit has a non-negative temperature difference that is greater than the first temperature difference, although the water temperature rises slowly, the large temperature difference poses a significant risk of delayed loading. Therefore, a fourth number of spare compressors are started to enhance the overall temperature regulation capacity of the unit and meet the system load requirements. When the chiller unit has a negative temperature difference that is less than or equal to the second temperature difference, although the water temperature decreases slowly, the current water temperature is lower than the set temperature, posing a relatively high risk of delayed load reduction leading to compressor shutdown due to reaching the shutdown temperature difference. Therefore, a significant load reduction operation is performed on the compressors already running. When the temperature difference of the chiller unit is negative and the absolute value of the temperature difference is greater than the first temperature difference, although the water temperature decreases slowly, the large temperature difference may pose a significant risk of untimely load reduction. Therefore, the fifth number of started compressors is shut down to reduce the load in advance, avoid compressor shutdown failures, and improve the stability of the chiller unit.

[0066] Combination Figure 6As shown, this disclosure provides an apparatus for controlling a chiller unit, including a processor 100 and a memory 101. Optionally, the apparatus may further include a communication interface 102 and a bus 103. The processor 100, communication interface 102, and memory 101 can communicate with each other via the bus 103. The communication interface 102 can be used for information transmission. The processor 100 can call logical instructions in the memory 101 to execute the chiller unit control method described in the above embodiment.

[0067] Furthermore, the logic instructions in the aforementioned memory 101 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium.

[0068] The memory 101, as a computer-readable storage medium, can be used to store software programs and computer-executable programs, such as program instructions / modules corresponding to the methods in the embodiments of this disclosure. The processor 100 executes functional applications and data processing by running the program instructions / modules stored in the memory 101, that is, it implements the method for chiller unit control described in the above embodiments.

[0069] The memory 101 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the terminal device. Furthermore, the memory 101 may include high-speed random access memory and may also include non-volatile memory.

[0070] This disclosure provides a chiller unit including multiple compressors; and the aforementioned device for controlling the chiller unit.

[0071] This disclosure provides a storage medium storing computer-executable instructions configured to perform the above-described method for controlling a chiller unit.

[0072] The aforementioned storage medium can be either transient or non-transient.

[0073] The technical solutions of this disclosure can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes one or more instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in this disclosure. The aforementioned storage medium can be a non-transitory storage medium, including: a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and other media capable of storing program code; it can also be a transient storage medium.

[0074] The foregoing description and accompanying drawings fully illustrate embodiments of this disclosure to enable those skilled in the art to practice them. Other embodiments may include structural, logical, electrical, procedural, and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. Moreover, the terminology used in this application is for describing embodiments only and is not intended to limit the claims. As used in the description of embodiments and claims, the singular forms “a,” “an,” and “the” are intended to equally include the plural forms unless the context clearly indicates otherwise. Similarly, the term “and / or” as used in this application means including one or more of the associated listed items and all possible combinations thereof. Additionally, when used in this application, the term "comprise" and its variations "comprises" and / or "comprising" refer to the presence of stated features, integrals, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof. Without further limitations, an element defined by the phrase "comprises a..." does not exclude the presence of other identical elements in the process, method, or apparatus that includes said element. In this document, each embodiment may focus on the differences from other embodiments, and similar or identical parts between embodiments can be referred to mutually. For methods, products, etc., disclosed in the embodiments, if they correspond to the method section disclosed in the embodiments, the relevant parts can be referred to the description of the method section.

[0075] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the embodiments of this disclosure. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0076] The methods and products (including but not limited to devices and equipment) disclosed in the embodiments herein can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units may be merely a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the shown or discussed units may be through some interfaces, and the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the units may be selected to implement this embodiment according to actual needs. Furthermore, the functional units in the embodiments of this disclosure 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.

[0077] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than that shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. In the descriptions corresponding to the flowcharts and block diagrams in the accompanying drawings, the operations or steps corresponding to different blocks may also occur in a different order than disclosed in the description, and sometimes there is no specific order between different operations or steps. For example, two consecutive operations or steps may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. Each block in a block diagram and / or flowchart, and combinations of blocks in a block diagram and / or flowchart, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

Claims

1. A method for controlling a chiller unit, characterized in that, The chiller unit includes multiple compressors; the method includes: In response to the start-up control command, the target number of compressors to be started is determined based on the temperature difference between the initial water temperature and the set temperature of the chiller unit. Start the compressors according to the target quantity; among them, prioritize starting the compressors with shorter running times; After a set time period, the corresponding operation is performed based on the water temperature change rate of the chiller unit; The corresponding operations include loading the compressor that has been started, unloading the compressor that has been started, starting the compressor, or turning off the compressor. The step of performing corresponding operations based on the water temperature change rate of the chiller unit includes: performing a loading operation on the started compressor when the water temperature change rate is greater than a first threshold; starting a second number of compressors when the water temperature change rate is greater than a second threshold; performing a unloading operation on the started compressors when the water temperature change rate is less than a third threshold; shutting down a third number of compressors when the water temperature change rate is less than or equal to the first threshold and greater than or equal to the third threshold; and performing the corresponding operation based on the temperature difference between the current water temperature of the chiller unit and the set temperature when the water temperature change rate is less than or equal to the first threshold and greater than or equal to the third threshold; wherein the second threshold is greater than the first threshold, the third threshold is greater than the fourth threshold, and the first threshold is greater than the third threshold. The step of performing the corresponding operation based on the temperature difference between the current water temperature of the chiller unit and the set temperature includes: increasing the load on the already started compressor when the temperature difference is non-negative and less than or equal to a first temperature difference; starting the compressor according to a fourth number when the temperature difference is non-negative and greater than the first temperature difference; reducing the load on the already started compressor when the temperature difference is negative and its absolute value is less than or equal to a second temperature difference; and shutting down the compressor according to a fifth number when the temperature difference is negative and its absolute value is greater than the first temperature difference.

2. The method according to claim 1, characterized in that, The step of determining the target number of compressors to be started based on the temperature difference between the initial water temperature and the set temperature of the chiller unit includes: The outlet water temperature is detected and determined as the initial water temperature; Calculate the start-up temperature difference between the initial water temperature and the set temperature; The target quantity is determined based on the startup temperature difference.

3. The method according to claim 2, characterized in that, Determining the target quantity based on the start-up temperature difference includes: Calculate N = K × S × δT; Wherein, N is the target quantity, K is the compressor start-up coefficient associated with the initial water temperature, S is the total number of compressors in the chiller unit, and δT is the start-up temperature difference.

4. The method according to claim 1, characterized in that, The step of starting the compressor according to the target quantity includes: If the target quantity is greater than or equal to the first quantity, start the compressor of the target quantity; If the target quantity is less than the first quantity, start the first quantity of compressors.

5. A device for controlling a chiller unit, comprising a processor and a memory storing program instructions, characterized in that, The processor is configured to perform the method for chiller unit control as described in any one of claims 1 to 4 when executing the program instructions.

6. A water chiller unit, characterized in that, It includes multiple compressors; and the device for controlling a chiller unit as described in claim 5.

7. A storage medium storing program instructions, characterized in that, When the program instructions are executed, they perform the method for controlling a chiller unit as described in any one of claims 1 to 4.

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