Method and device for anti-surge of centrifugal compressor unit, centrifugal compressor unit, storage medium

Abstract

This application relates to the field of centrifuge unit control technology, and discloses a method for preventing surge in centrifuge units. The method includes determining whether the compressor speed meets a preset speed condition when surge occurs. If the compressor speed does not meet the preset speed condition, the compressor inlet guide vane is closed. If the compressor speed meets the preset condition, the refrigerant-side bypass valve is opened, and / or, the water-side bypass valve is opened. By controlling the opening and closing of the inlet guide vane, the refrigerant-side bypass valve, and the water-side bypass valve, the compressor pressure ratio is reduced from multiple dimensions, including compressor cooling capacity, evaporation pressure, and condensation pressure, to perform surge prevention operation on the centrifuge unit. This enriches the means of preventing surge in centrifuge units, thereby improving the reliability of the centrifuge unit. This application also discloses a device for preventing surge in centrifuge units, a centrifuge unit, and a storage medium.

Description

Technical Field

[0001] This application relates to the field of centrifuge unit control technology, such as a method and apparatus for preventing surge in centrifuge units, centrifuge units, and storage media. Background Technology

[0002] Currently, to prevent compressor surge, the common method for variable frequency drives (VFDs) is to set an anti-surge line. This involves plotting the pressure ratio (condensing pressure / evaporating pressure) on the x-axis and the corresponding surge frequency on the y-axis to form the compressor's surge line. Adding a safety margin to this surge line creates the unit's anti-surge line. During operation, pressure sensors obtain the condensing and evaporating pressures, calculating the current compressor operating pressure ratio. This pressure ratio is then substituted into the anti-surge line formula to calculate the minimum operating frequency at that pressure ratio. The actual operating frequency of the unit must not be lower than the minimum frequency calculated by the anti-surge line to prevent surge. However, in practical applications, the load demand on the unit varies, often requiring a wide operating range. As the unit load and operating conditions change, the compressor operating pressure ratio also changes. Current anti-surge control methods suffer from problems such as the anti-surge line and the surge line not perfectly aligning, resulting in poor accuracy, a narrowed operating range, significantly reduced energy efficiency, and compromised reliability.

[0003] The related technology discloses a variable frequency centrifugal chiller unit and its control method. The unit includes a throttling valve and a hot gas bypass valve connected in parallel between the condenser and evaporator. The compressor's inlet and outlet are connected to the evaporator and condenser, respectively. A frequency converter controls the compressor's frequency. Both the condenser and evaporator are equipped with pressure measuring devices for measuring absolute pressure. The compressor is equipped with a vibration measuring device. The control unit receives data from the pressure measuring devices, the hot gas bypass valve, and the vibration measuring device, processes the data, and controls the frequency converter and the hot gas bypass valve based on the calculation results. By implementing zoned control of the unit's operating range, the unit can self-diagnose surge and self-correct its safe operating range. This makes the anti-surge control of the unit more accurately match the actual surge point of the unit, not only expanding the unit's operating range but also improving its operating performance and reliability.

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

[0005] Using relevant technologies to correct the safe operating range through hot gas bypass valves can precisely avoid surge. Although this can broaden the operating range of the unit, relying solely on hot gas bypass valves to prevent surge is too simplistic and lacks reliability. 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 anti-surge operation of centrifuge units, a centrifuge unit, and a storage medium, which can perform anti-surge operation on centrifuge units from multiple dimensions, enriching the means of anti-surge operation of centrifuge units and thus improving the reliability of centrifuge units.

[0008] In some embodiments, the centrifuge unit includes a compressor, an evaporator connected to the compressor inlet, and a condenser connected to the compressor outlet. The evaporator and condenser are connected via a refrigerant-side bypass valve, and the chilled water inlet side of the evaporator and the cooling water inlet side of the condenser are connected via a water-side bypass valve. The method includes: in the event of compressor surge, determining whether the compressor speed meets a preset speed condition; if the compressor speed does not meet the preset speed condition, closing the compressor inlet guide vanes; if the compressor speed meets the preset condition, opening the refrigerant-side bypass valve, and / or opening the water-side bypass valve.

[0009] In some embodiments, the apparatus includes a processor and a memory storing program instructions, wherein the processor is configured to execute the aforementioned method for anti-surge of a centrifuge unit when executing the program instructions.

[0010] In some embodiments, the centrifuge unit includes:

[0011] compressor;

[0012] Evaporator, connected to the compressor inlet;

[0013] The condenser is connected to the compressor discharge port and then to the evaporator via a refrigerant-side bypass valve; the chilled water inlet side of the evaporator and the cooling water inlet side of the condenser are connected via a water-side bypass valve; and

[0014] The aforementioned device for preventing surge in centrifuge units.

[0015] In some embodiments, the storage medium stores program instructions that, when executed, perform the aforementioned method for preventing surge in centrifuge units.

[0016] The method and apparatus for anti-surge of centrifuge units, the centrifuge unit, and the storage medium provided in this disclosure can achieve the following technical effects:

[0017] In the event of compressor surge, it is determined whether the compressor speed meets the preset speed condition. If the compressor speed does not meet the preset speed condition, the compressor inlet guide vane is closed. If the compressor speed meets the preset condition, the refrigerant side bypass valve is opened, and / or, the water side bypass valve is opened. By controlling the opening and closing of the inlet guide vane, the refrigerant side bypass valve, and the water side bypass valve, the compressor pressure ratio is reduced from multiple dimensions, including compressor cooling capacity, evaporation pressure, and condensation pressure, to perform anti-surge operation on the centrifugal chiller unit. This enriches the anti-surge methods for centrifugal chiller units, thereby improving the reliability of the centrifugal chiller unit.

[0018] The above general description and the description below are exemplary and illustrative only and are not intended to limit this application. Attached Figure Description

[0019] 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:

[0020] Figure 1 This is a schematic diagram of the structure of a centrifuge unit provided in an embodiment of this disclosure;

[0021] Figure 2 This is a schematic diagram of a method for preventing surge in a centrifuge unit provided in an embodiment of this disclosure;

[0022] Figure 3 This is a schematic diagram of another method for preventing surge in centrifuge units provided in an embodiment of this disclosure;

[0023] Figure 4 This is a schematic diagram of another method for preventing surge in centrifuge units provided in an embodiment of this disclosure;

[0024] Figure 5 This is a schematic diagram of another method for preventing surge in centrifuge units provided in an embodiment of this disclosure;

[0025] Figure 6 This is a schematic diagram of another method for preventing surge in centrifuge units provided in an embodiment of this disclosure;

[0026] Figure 7 This is a schematic diagram of a device for preventing surge in a centrifuge unit provided in an embodiment of this disclosure. Detailed Implementation

[0027] 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.

[0028] 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.

[0029] Unless otherwise stated, the term "multiple" means two or more.

[0030] 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.

[0031] 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.

[0032] 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.

[0033] like Figure 1 As shown in the figure, this disclosure discloses a centrifuge unit, including: a compressor 1, an evaporator 2 connected to the air inlet of the compressor 1 and a condenser 3 connected to the exhaust port of the compressor 1. The evaporator 2 and the condenser 3 are connected by a refrigerant side bypass valve 4. The chilled water inlet side 21 of the evaporator 2 and the cooling water inlet side 31 of the condenser 3 are connected by a water side bypass valve 5.

[0034] Based on the structure of the centrifuge unit described above, this disclosure provides a method for preventing surge in a centrifuge unit. For example... Figure 2 As shown, the method includes:

[0035] S01, when the centrifugal chiller unit experiences compressor surge, it determines whether the compressor speed meets the preset speed condition.

[0036] S02, when the compressor speed does not meet the preset speed condition, the centrifugal chiller unit closes the compressor inlet guide vanes.

[0037] S03, when the compressor speed of the centrifuge unit meets the preset conditions, the refrigerant side bypass valve is opened, and / or the water side bypass valve is opened.

[0038] The method for preventing surge in centrifugal chillers provided in this disclosure determines whether the compressor speed meets a preset speed condition when surge occurs. If the compressor speed does not meet the preset speed condition, the compressor inlet guide vanes are closed. This reduces the compressor's cooling capacity and simultaneously causes an increase in the compressor's evaporating pressure and a decrease in the condensing pressure, thereby reducing the pressure ratio (condensing pressure / evaporating pressure = pressure ratio). There is a relationship between the compressor surge line and the pressure ratio; the higher the pressure ratio, the higher the surge line and the more prone to surge. Therefore, closing the compressor inlet guide vanes and reducing the pressure ratio can prevent surge. If the compressor speed meets the preset condition, the refrigerant-side bypass valve and / or the water-side bypass valve are opened. By opening the refrigerant-side bypass valve, the high-temperature, high-pressure gas in the condenser can flow back to the evaporator, causing an increase in evaporation pressure. After the high-temperature, high-pressure gas exits the condenser, the condensation pressure decreases, resulting in a lower pressure ratio and ultimately preventing surge. Similarly, by opening the water-side bypass valve, high-temperature water from the condenser's cooling water inlet can be delivered to the evaporator's chilled water inlet. Since evaporation and condensation pressures are positively correlated with water temperature, the arrival of this high-temperature water causes an increase in the refrigerant-side evaporation pressure within the evaporator, further reducing the pressure ratio and preventing surge. Therefore, by controlling the opening and closing of the inlet guide vanes, the refrigerant-side bypass valve, and the water-side bypass valve, the compressor's pressure ratio is reduced from multiple dimensions—compressor cooling capacity, evaporation pressure, and condensation pressure—to perform anti-surge operation on the centrifugal chiller unit. This enriches the anti-surge measures for centrifugal chiller units, thereby improving their reliability.

[0039] This disclosure provides a method for preventing surge in centrifuge units. For example... Figure 3 As shown, the method includes:

[0040] S21, the centrifugal chiller unit detects the current speed of the compressor when the compressor experiences surge.

[0041] S22, if the speed difference between the current speed and the surge speed of the centrifugal chiller unit is greater than the difference threshold, it is determined that the speed of the compressor does not meet the preset speed condition.

[0042] S23, when the speed difference of the centrifugal chiller is less than or equal to the difference threshold, the speed of the compressor is determined to meet the preset speed condition.

[0043] S02, when the compressor speed does not meet the preset speed condition, the centrifugal chiller unit closes the compressor inlet guide vanes.

[0044] S03, when the compressor speed of the centrifuge unit meets the preset conditions, the refrigerant side bypass valve is opened, and / or the water side bypass valve is opened.

[0045] The method for preventing surge in centrifuge units provided in this disclosure detects the current compressor speed when surge occurs. If the difference between the current speed and the surge speed is greater than a threshold, the current compressor speed is significantly different from the surge speed, and the probability of surge is low. Therefore, it is determined that the compressor speed does not meet the preset speed condition. If the speed difference is less than or equal to the threshold, the current compressor speed is significantly different from the surge speed, and the probability of surge is high. Therefore, it is determined that the compressor speed meets the preset speed condition.

[0046] This disclosure provides a method for preventing surge in centrifuge units. For example... Figure 4 As shown, the method includes:

[0047] S01, when the centrifugal chiller unit experiences compressor surge, it determines whether the compressor speed meets the preset speed condition.

[0048] S02, when the compressor speed does not meet the preset speed condition, the centrifugal chiller unit closes the compressor inlet guide vanes.

[0049] S31, when the compressor speed meets the preset conditions, the centrifugal chiller unit opens the refrigerant side bypass valve and / or the water side bypass valve according to the compressor pressure ratio.

[0050] The method for preventing surge in centrifuge units provided in this disclosure involves a centrifuge unit where, when the compressor speed meets preset conditions, the difference between the current compressor speed and the surge speed is small, increasing the probability of compressor surge. Therefore, the centrifuge unit opens the refrigerant-side bypass valve and / or the water-side bypass valve based on the compressor pressure ratio. Based on the compressor pressure ratio, the centrifuge unit can more precisely reduce the compressor pressure ratio by opening the refrigerant-side bypass valve and / or the water-side bypass valve.

[0051] This disclosure provides a method for preventing surge in centrifuge units. For example... Figure 5 As shown, the method includes:

[0052] S01, when the centrifugal chiller unit experiences compressor surge, it determines whether the compressor speed meets the preset speed condition.

[0053] S02, when the compressor speed does not meet the preset speed condition, the centrifugal chiller unit closes the compressor inlet guide vanes.

[0054] S41, when the compressor speed meets the preset conditions and the pressure ratio is greater than the first ratio, the centrifugal chiller unit opens the refrigerant side bypass valve or the water side bypass valve.

[0055] S42, when the centrifuge unit has a pressure ratio greater than the second ratio, the fluorine side bypass valve and the water side bypass valve are opened.

[0056] The second ratio is greater than the first ratio. Closing the compressor inlet guide vanes includes: reducing the opening of the inlet guide vanes to a level corresponding to the compressor speed; determining whether surge has stopped; and closing the inlet guide vanes if the surge has not stopped. Reducing the inlet guide vane opening based on the compressor speed, and then closing the inlet guide vanes if reducing the opening still fails to stop the surge, can improve the energy efficiency of the centrifuge unit.

[0057] The method for preventing surge in centrifugal chillers provided in this disclosure calculates the compressor pressure ratio when the compressor speed meets preset conditions. If the pressure ratio is greater than a first ratio value, the pressure ratio is relatively high, and either increasing the evaporation pressure with a single high-temperature refrigerant or by using only high-temperature water can reduce the pressure ratio to a safe range, preventing surge. Therefore, only the refrigerant-side bypass valve or the water-side bypass valve is opened. If the pressure ratio is greater than a second ratio value, the pressure ratio is also high, and either increasing the evaporation pressure with a single high-temperature refrigerant or by using only high-temperature water cannot promptly reduce the pressure ratio to a safe range. Therefore, both the refrigerant-side bypass valve and the water-side bypass valve are opened simultaneously to rapidly reduce the compressor pressure ratio to a safe range.

[0058] This disclosure provides a method for preventing surge in centrifuge units. For example... Figure 6 As shown, the method includes:

[0059] S01, when the centrifugal chiller unit experiences compressor surge, it determines whether the compressor speed meets the preset speed condition.

[0060] S02, when the compressor speed does not meet the preset speed condition, the centrifugal chiller unit closes the compressor inlet guide vanes.

[0061] S41, when the compressor speed meets the preset conditions and the pressure ratio is greater than the first ratio, the centrifugal chiller unit opens the refrigerant side bypass valve or the water side bypass valve.

[0062] S51, the centrifugal chiller unit determines whether the compressor surge has stopped.

[0063] S52, if the compressor surge of the centrifugal chiller unit has not yet stopped, open the refrigerant side bypass valve or the water side bypass valve that is in the closed state.

[0064] S42, when the centrifuge unit has a pressure ratio greater than the second ratio, the fluorine side bypass valve and the water side bypass valve are opened.

[0065] In this centrifugal chiller unit, when the compressor speed meets preset conditions and the pressure ratio is greater than a first ratio, the water-side bypass valve can be opened first. Then, it is determined whether the compressor surge has stopped. If the compressor surge has not stopped, the refrigerant-side bypass valve, which is in the closed state, is opened. By first opening the water-side bypass valve, the compressor pressure ratio can be reduced by increasing the evaporation pressure. If the surge still cannot be stopped, it means that simply increasing the evaporation pressure is not enough to effectively reduce the pressure ratio in a timely manner. At this time, the compressor pressure ratio is reduced by opening the refrigerant-side bypass valve, which is in the closed state. Opening the refrigerant-side bypass valve allows the high-temperature, high-pressure gas in the condenser to flow back to the evaporator. This not only increases the evaporation pressure, but also reduces the condensation pressure after the high-temperature, high-pressure gas is output from the condenser. By increasing the evaporation pressure and decreasing the condensation pressure, the compressor pressure ratio can be reduced more quickly, thereby avoiding surge.

[0066] When using the anti-surge method for centrifugal chillers provided in this embodiment, after opening the refrigerant-side bypass valve or the water-side bypass valve, the evaporation pressure may rise slowly and the condensation pressure may drop slowly because the pressure ratio is reduced by only using a single high-temperature refrigerant to increase the evaporation pressure or by only using high-temperature water. Therefore, in order to reduce the pressure ratio to within the safe pressure ratio range in a timely manner, the centrifugal chiller determines whether the compressor surge has stopped. If the compressor surge has not stopped, the refrigerant-side bypass valve or the water-side bypass valve, which is in the closed state, is opened to quickly reduce the pressure ratio and avoid surge.

[0067] Optionally, the centrifuge unit determines whether the compressor is experiencing surge by the following method: the centrifuge unit obtains the compressor's discharge pressure; the centrifuge unit calculates a first rate of change of the compressor's discharge pressure; and the centrifuge unit determines whether the compressor is experiencing surge based on the first rate of change.

[0068] In this way, the centrifuge unit obtains the compressor's discharge pressure and calculates the first rate of change of the compressor's discharge pressure. Finally, based on the first rate of change, it determines whether the compressor is experiencing surge. Since surge during compressor operation mainly manifests as the compressor's discharge not being able to reach the condenser through the discharge port, causing discharge backflow, the discharge pressure change rate can accurately determine whether the compressor is experiencing surge. During normal operation of the centrifuge unit, the discharge pressure change is small, but when slight surge occurs, the discharge pressure change increases accordingly.

[0069] Optionally, the centrifuge unit determines whether the compressor is experiencing surge based on the first rate of change, including: the centrifuge unit determines that the compressor is experiencing surge when the first rate of change is greater than a first threshold and continues for a set number of times.

[0070] Thus, since surge during compressor operation mainly manifests as the compressor exhaust failing to reach the condenser through the exhaust port, causing exhaust backflow, the rate of change of exhaust pressure can accurately determine whether the compressor is experiencing surge. During normal operation of the centrifugal chiller, the exhaust pressure change is small; however, when a slight surge occurs, the exhaust pressure change increases accordingly. If the first rate of change is greater than a first threshold and continues for a set number of times, it indicates that the compressor exhaust pressure change is significant, and the centrifugal chiller can determine that the compressor is experiencing surge. For example, exhaust pressure values ​​are continuously read every 1 second, 10 consecutive numbers are read, the average of the 10 numbers is calculated, and the difference between the maximum and minimum values ​​is calculated. The ratio of the difference to the average value is used as the first rate of change. If the first rate of change is greater than the first threshold (0.15), the surge flag is set; if the first rate of change is less than 0.15, the flag is reset. Recording the surge flag setting three times consecutively indicates that the centrifugal chiller is experiencing surge, and the compressor enters anti-surge logic.

[0071] Optionally, the centrifuge unit determines whether the compressor is experiencing surge by the following method: the centrifuge unit acquires the vibration value of the compressor; the centrifuge unit calculates a second rate of change of the compressor vibration value; and the centrifuge unit determines whether the compressor is experiencing surge based on the second rate of change.

[0072] In this way, the centrifuge unit acquires the compressor's vibration value and calculates the second rate of change of the compressor's vibration value. Finally, based on the second rate of change, it determines whether the compressor is experiencing surge. Since surge during compressor operation is mainly manifested in the compressor's exhaust being unable to reach the condenser through the exhaust port, causing significant compressor vibration, the rate of change of vibration value can accurately determine whether the compressor is experiencing surge. During normal operation of the centrifuge unit, the vibration value changes relatively little, but when slight surge occurs, the vibration value changes more significantly.

[0073] Optionally, the centrifuge unit determines whether the compressor is experiencing surge based on the first rate of change, including: if the centrifuge unit determines that the compressor is experiencing surge when the second rate of change is greater than the second threshold and continues for a set number of times.

[0074] Thus, since surge during compressor operation mainly manifests as the compressor exhaust failing to reach the condenser through the exhaust port, causing exhaust backflow and significant compressor vibration changes, the vibration value change rate can accurately determine whether the compressor is experiencing surge. During normal operation, the vibration value change is relatively small; however, when slight surge occurs, the vibration value change increases accordingly. If the second change rate is greater than the second threshold and continues for a set number of times, it indicates that the compressor vibration value change is significant, and the centrifugal unit can determine that the compressor is experiencing surge. For example, vibration values ​​are continuously read every 1 second, for a total of 10 readings. The average of these 10 readings, along with the difference between the maximum and minimum values, is calculated. The ratio of this difference to the average value is used as the second change rate. If the second change rate is greater than the second threshold (0.15), the surge flag is set; if the second change rate is less than 0.15, the flag is reset. Recording the surge flag setting three times consecutively indicates that the centrifugal unit is experiencing surge, and the compressor enters anti-surge logic.

[0075] Combination Figure 7 As shown, this disclosure provides an apparatus for preventing surge in a centrifuge 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 method for preventing surge in a centrifuge unit described in the above embodiment.

[0076] 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.

[0077] 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, thereby implementing the method for anti-surge of centrifuge units in the above embodiments.

[0078] 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.

[0079] This disclosure provides a centrifuge unit, including a compressor, an evaporator connected to the compressor inlet, and a condenser connected to the compressor outlet. The evaporator and condenser are connected via a refrigerant-side bypass valve, and the chilled water inlet side of the evaporator and the cooling water inlet side of the condenser are connected via a water-side bypass valve; as well as the aforementioned device for preventing surge in the centrifuge unit.

[0080] This disclosure provides a storage medium storing computer-executable instructions configured to perform the above-described method for preventing surge in centrifuge units.

[0081] The aforementioned storage medium can be either transient or non-transient.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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 preventing surge in centrifuge units, characterized in that, The centrifuge unit includes a compressor, an evaporator connected to the compressor's inlet, and a condenser connected to the compressor's outlet. The evaporator and the condenser are connected via a refrigerant-side bypass valve, and the chilled water inlet side of the evaporator and the cooling water inlet side of the condenser are connected via a water-side bypass valve. The method includes: In the event of compressor surge, it is determined whether the compressor speed meets a preset speed condition; wherein, the current speed of the compressor is detected; if the speed difference between the current speed and the surge speed is greater than a difference threshold, it is determined that the compressor speed does not meet the preset speed condition; if the speed difference is less than or equal to the difference threshold, it is determined that the compressor speed meets the preset speed condition. If the compressor speed does not meet the preset speed condition, the compressor inlet guide vanes are closed. When the compressor speed meets the preset speed condition, the refrigerant bypass valve is opened to return the high-temperature and high-pressure gas in the condenser to the evaporator, and / or the water bypass valve is opened to transport the high-temperature water from the cooling water inlet side of the condenser to the chilled water inlet side of the evaporator.

2. The method according to claim 1, characterized in that, The step of opening the fluoride-side bypass valve and / or opening the water-side bypass valve includes: Based on the pressure ratio of the compressor, open the refrigerant-side bypass valve and / or open the water-side bypass valve.

3. The method according to claim 2, characterized in that, The step of opening the refrigerant-side bypass valve and / or opening the water-side bypass valve according to the pressure ratio of the compressor includes: When the pressure ratio is greater than the first ratio, the fluoride-side bypass valve or the water-side bypass valve is opened; When the pressure ratio is greater than the second ratio, the fluoride-side bypass valve and the water-side bypass valve are opened; The second ratio is greater than the first ratio.

4. The method according to claim 3, characterized in that, After opening the fluorine-side bypass valve or the water-side bypass valve, the method further includes: Determine whether the surge of the compressor has stopped; If the compressor surge has not stopped, open the fluorine-side bypass valve or the water-side bypass valve, which is in the closed state.

5. The method according to any one of claims 1 to 4, characterized in that, The following methods are used to determine whether the compressor is experiencing surge: Obtain the discharge pressure of the compressor; Calculate the first rate of change of the compressor discharge pressure; Based on the first rate of change, it is determined whether the compressor is experiencing surge.

6. The method according to claim 5, characterized in that, The step of determining whether the compressor is experiencing surge based on the first rate of change includes: If the first rate of change is greater than the first threshold and continues for a set number of times, it is determined that the compressor is experiencing surge.

7. A device for preventing surge in a centrifuge unit, comprising a processor and a memory storing program instructions, characterized in that, The processor is configured to, when executing the program instructions, perform the method for anti-surge of a centrifuge unit as described in any one of claims 1 to 6.

8. A centrifuge unit, characterized in that, include: compressor; Evaporator, connected to the compressor inlet; The condenser is connected to the compressor discharge port and connected to the evaporator via a refrigerant bypass valve. The chilled water inlet side of the evaporator and the cooling water inlet side of the condenser are connected by a water-side bypass valve; and... The device for preventing surge in centrifuge units as described in claim 7.

9. A storage medium storing program instructions, characterized in that, When the program instructions are executed, they perform the method for anti-surge of centrifuge units as described in any one of claims 1 to 6.

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