Optimization control method and optimization control device for air conditioning unit and air conditioning unit

Abstract

The invention provides an optimization control method and device for an air conditioning unit and the air conditioning unit. The method comprises the steps that unit operation data are obtained, whether the air conditioning unit is in a load keeping state or not is determined at least based on the unit operation data, and the load keeping state is the unit operation state in which fluctuation of the unit operation data is smaller than a corresponding threshold value; under the condition that the air conditioning unit is in the load keeping state, the opening degree of a throttling device of the air conditioning unit is traversed till the target opening degree corresponding to the maximum value of the performance coefficient of the unit is determined; and the opening degree of the throttling device is adjusted to the target opening degree, and the target opening degree is maintained to control the air conditioning unit to operate. According to the method, the air conditioning unit is controlled to conduct opening optimization of the throttling device under the current working condition, and the problems that in the prior art, a liquid level control and database experience control method cannot ensure that the operation state of the throttling device of the unit is optimal within the full working condition range, and consequently energy efficiency is reduced and energy consumption is increased are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioning control, and in particular to an optimization control method, an optimization control device, a computer-readable storage medium and an air conditioning unit. Background Art

[0002] The vapor compression refrigeration cycle includes four essential processes: compression, condensation, throttling, and evaporation. During the throttling process, the refrigerant mass flow rate of the throttling device is proportional to the system pressure difference before and after throttling, as well as the throttling aperture. In order to adapt to the differences in different operating conditions of the unit, to ensure sufficient refrigerant supply under all working conditions, and to ensure stable, reliable and efficient system operation, most units use variable throttling aperture throttling devices. According to the changes in the unit's operating status (evaporation and condensation pressure, compressor suction and exhaust volume, etc.), the size of the throttling aperture is adjusted to match the current state, making the unit more reliable and energy efficient.

[0003] The control methods of throttling devices in the prior art are mostly based on liquid level control or database experience value control, but liquid level control can only achieve the optimal liquid level under a certain working condition, and database experience value control requires a large amount of different working condition data as support to ensure the accuracy of model calculation.

[0004] In summary, the control method of the throttling device in the prior art cannot ensure that the opening of the throttling device is optimal under all working conditions, resulting in a problem of reduced energy efficiency of the air-conditioning unit. Summary of the invention

[0005] The main purpose of the present application is to provide an optimization control method, an optimization control device, a computer-readable storage medium and an air-conditioning unit for an air-conditioning unit, so as to at least solve the problem that the liquid level control and database experience control methods in the prior art cannot ensure the optimal operating state of the throttling device of the unit within the full operating range, resulting in reduced energy efficiency and increased energy consumption.

[0006] In order to achieve the above-mentioned purpose, according to one aspect of the present application, there is provided an optimization control method for an air-conditioning unit, comprising: acquiring unit operation data, and determining whether the air-conditioning unit is in a load holding state at least based on the unit operation data, the load holding state being a unit operation state in which the fluctuation of the unit operation data is less than a corresponding threshold value; when the air-conditioning unit is in the load holding state, traversing the opening of the throttling device of the air-conditioning unit until a target opening corresponding to the maximum value of the unit performance coefficient is determined; adjusting the opening of the throttling device to the target opening, and maintaining the target opening to control the operation of the air-conditioning unit.

[0007] Optionally, traversing the opening of the throttling device of the air-conditioning unit until determining the target opening corresponding to the maximum value of the unit performance coefficient includes: obtaining the opening of the throttling device at the current moment to obtain a first opening, taking the first opening as a reference, adjusting the opening of the throttling device according to a preset number of steps to traverse all the openings of the throttling device, and recording the unit performance coefficient corresponding to each opening to obtain a target performance group; determining the opening corresponding to the maximum value of the unit performance coefficient in the target performance group as the target opening. Optionally, recording the unit performance coefficient includes: when the air-conditioning unit is in cooling mode, obtaining the unit cooling capacity and unit operating load of the air-conditioning unit; calculating the ratio of the unit cooling capacity to the unit operating load to obtain the unit performance coefficient; when the air-conditioning unit is in heating mode, obtaining the unit heating capacity and unit operating load of the air-conditioning unit; calculating the ratio of the unit heating capacity to the unit operating load to obtain the unit performance coefficient.

[0008] Optionally, based on the first opening, the opening of the throttling device is adjusted according to a preset number of steps to traverse all the openings of the throttling device, and the unit performance coefficient corresponding to each opening is recorded to obtain a target performance group, including: based on the first opening, increasing the preset number of steps at each preset time interval and recording the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is fully opened to obtain a first performance group; adjusting the opening of the throttling device to the first opening; based on the first opening, reducing the preset number of steps at each preset time interval and recording the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is fully closed to obtain a second performance group; determining the target performance group based on the first performance group and the second performance group.

[0009] Optionally, recording the unit performance coefficient includes: when the air-conditioning unit is in cooling mode, calculating the unit cooling capacity based on a first water flow rate and a first temperature difference through a thermal power formula, the first water flow rate is the water flow rate of the evaporator of the air-conditioning unit, and the first temperature difference is the inlet and outlet water temperature difference of the evaporator; calculating the ratio of the unit cooling capacity to the unit power consumption to obtain the unit performance coefficient; when the air-conditioning unit is in heating mode, calculating the unit heating capacity based on a second water flow rate and a second temperature difference through a thermal power formula, the second water flow rate is the water flow rate of the condenser of the air-conditioning unit, and the second temperature difference is the inlet and outlet water temperature difference of the condenser; calculating the ratio of the unit heating capacity to the unit power consumption to obtain the unit performance coefficient.

[0010] Optionally, obtaining the first water flow rate or obtaining the second water flow rate includes: obtaining a first pressure difference or a second pressure difference, the first pressure difference being the inlet and outlet water pressure difference of the evaporator, and the second pressure difference being the inlet and outlet water pressure difference of the condenser; substituting the first pressure difference or the second pressure difference into a first preset formula to obtain the first water flow rate or the second water flow rate, the first preset formula being obtained by fitting the inlet and outlet water pressure difference and the water flow rate of the evaporator or the condenser in the historical operation data of the air-conditioning unit.

[0011] Optionally, after obtaining the unit operation data, the method also includes: when the air-conditioning unit is not in the load holding state, obtaining a first liquid level or a second liquid level, the first liquid level being the condenser liquid level, and the second liquid level being the evaporator liquid level; when the first liquid level or the second liquid level is less than a first threshold, based on the deviation between the first liquid level or the second liquid level and the first threshold, increasing the opening of the throttling device; when the first liquid level or the second liquid level is greater than the first threshold, based on the deviation between the first liquid level or the second liquid level and the first threshold, reducing the opening of the throttling device.

[0012] According to another aspect of the present application, there is provided an optimization control device for an air-conditioning unit, the device comprising: a first acquisition unit, for acquiring unit operation data, and determining whether the air-conditioning unit is in a load holding state at least based on the unit operation data, the load holding state being a unit operation state in which a fluctuation of the unit operation data is less than a corresponding threshold value; a first control unit, for traversing the opening of a throttling device of the air-conditioning unit when the air-conditioning unit is in the load holding state until a target opening corresponding to a maximum value of the unit performance coefficient is determined; and a second control unit, for adjusting the opening of the throttling device to the target opening, and maintaining the opening at the target opening to control the operation of the air-conditioning unit.

[0013] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute any one of the methods described.

[0014] According to another aspect of the present application, an air-conditioning unit is provided, comprising: one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include methods for executing any one of the described methods.

[0015] Applying the technical solution of the present application, in the above-mentioned optimization control method for the air-conditioning unit, first, the unit operation data is obtained, and it is determined whether the air-conditioning unit is in a load holding state at least based on the unit operation data, and the load holding state is the unit operation state in which the fluctuation of the unit operation data is less than the corresponding threshold value; then, when the air-conditioning unit is in the load holding state, the opening of the throttling device of the air-conditioning unit is traversed until the target opening corresponding to the maximum value of the unit performance coefficient is determined; finally, the opening of the throttling device is adjusted to the target opening, and the target opening is maintained to control the operation of the air-conditioning unit. The present application can automatically find the optimal throttling device opening when the air-conditioning unit is in a load holding state by monitoring the unit operation data in real time and adjusting the opening of the throttling device to maximize the unit performance coefficient, thereby solving the problem that the liquid level control and database experience control methods in the prior art cannot ensure that the operation state of the throttling device of the unit is optimal within the full range of operating conditions, resulting in reduced energy efficiency and increased energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic structural diagram of an optimization control system for an air-conditioning unit provided according to an embodiment of the present application is shown;

[0017] Figure 2 A schematic flow chart of an optimal control method for an air-conditioning unit provided according to an embodiment of the present application is shown;

[0018] Figure 3 A structural block diagram of an optimization control device for an air-conditioning unit provided according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0019] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0020] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0022] As introduced in the background technology, the liquid level control method of the throttling device in the prior art measures the liquid level of the condenser or evaporator by installing a liquid level sensor, determines the optimal liquid level under various working conditions through calibration experiments, and adjusts the size of the throttling device aperture by controlling the liquid level of the evaporator or condenser. However, the above method has the problem that the control target liquid level is only the optimal liquid level under the calibration conditions, and the control target is relatively single, which cannot ensure the dynamic optimal control of the air-conditioning unit under all working conditions; the database experience value control of the throttling device, by establishing a corresponding database, the computer group calculates the optimal operating opening of the throttling device under various operating conditions, so that the throttling device controls the opening according to the model calculation value, but the above method When the amount of data in the database is insufficient, the accuracy of model training is insufficient, resulting in deviations in the calculated optimal operating opening, and the problem that the throttling device control cannot be in the optimal state. In summary, the control method of the throttling device in the prior art cannot ensure that the throttling device opening is optimal under all operating conditions, resulting in reduced energy efficiency of the air-conditioning unit. In order to solve the problem that the liquid level control and database experience control methods in the prior art cannot ensure that the operating state of the throttling device of the unit is optimal within the full operating range, resulting in reduced energy efficiency and increased energy consumption, the embodiments of the present application provide an optimal control method, an optimal control device, a computer-readable storage medium and an air-conditioning unit.

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0024] In one embodiment of the present application, an optimal control system (refrigeration) for an air-conditioning unit is provided, which is used to solve the problem of inefficient operation of the air-conditioning unit due to poor control of the throttling device, such as Figure 1 As shown, the above-mentioned optimization control system includes an evaporator, a compressor, a condenser, a throttling device, a temperature sensor 1, a temperature sensor 2, a pressure difference sensor and a frequency converter or an electric meter.

[0025] Among them, the above-mentioned evaporator, compressor, condenser and throttling device constitute a refrigeration cycle system, the throttling device can adjust the size of the throttling aperture, temperature sensor 1 and temperature sensor 2 are used to monitor the inlet and outlet water temperatures of the evaporator respectively, the pressure difference sensor is used to monitor the inlet and outlet water pressure difference of the evaporator, and the inverter and the electric meter are used to monitor the real-time power consumption of the air-conditioning unit.

[0026] Furthermore, if the optimal control system is a heating cycle system, the temperature sensor 1, the temperature sensor 2 and the pressure difference sensor are installed on the condenser to measure the inlet and outlet water temperatures and the inlet and outlet water pressure difference of the condenser.

[0027] In this embodiment, a method for optimizing the control of an air-conditioning unit running on a computer terminal or a similar computing device 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.

[0028] Figure 2 1 is a flow chart of an optimal control method for an air conditioning unit according to an embodiment of the present application. Figure 2 As shown, the method comprises the following steps:

[0029] Step S201, obtaining unit operation data, and determining whether the air conditioning unit is in a load holding state at least based on the unit operation data, the load holding state being a unit operation state in which a fluctuation of the unit operation data is less than a corresponding threshold;

[0030] Specifically, by acquiring the above-mentioned unit operation data in real time, it is determined whether the air-conditioning unit is in a load holding state, that is, the fluctuation of the unit operation data is less than a preset threshold.

[0031] In a specific implementation, the above-mentioned unit operation data include, but are not limited to, key parameters such as chilled water outlet temperature, compressor operating frequency, and compressor guide vane opening. Corresponding thresholds are set for different unit operation data to determine whether the air-conditioning unit is in a stable operating state, that is, the above-mentioned load holding state. It can be understood that the above-mentioned control is used to ensure the stability of the operating conditions of the air-conditioning unit, avoiding optimization during the change of operating conditions, resulting in the optimization result not being applicable to the changed operating conditions, and causing the target operating condition to be not the optimal operating condition.

[0032] Step S202, when the air-conditioning unit is in the load holding state, traverse the opening of the throttling device of the air-conditioning unit until a target opening corresponding to the maximum value of the unit performance coefficient is determined;

[0033] Specifically, after confirming that the air-conditioning unit is in a load-holding state, the system automatically adjusts the throttling device opening of the air-conditioning unit, and gradually seeks the target opening that can maximize the unit's coefficient of performance. The unit's coefficient of performance is determined by the ratio of the air-conditioning unit's cooling capacity or heating capacity to the operating load.

[0034] It can be understood that the present application is configured to traverse all possible openings of the throttling device under the stable operating conditions at the current moment, and to measure the performance of the air-conditioning unit at different openings by using the unit performance coefficient as an indicator, and to take the opening with the maximum value of the unit performance coefficient as the target opening, thereby realizing the optimization of the throttling device opening under all operating conditions.

[0035] Step S203, adjusting the opening of the throttling device to the target opening, and maintaining the target opening to control the operation of the air-conditioning unit.

[0036] Specifically, after finding the optimal opening, the system maintains the throttling device opening at the target opening to achieve efficient and stable operation of the air-conditioning unit until the operating state of the air-conditioning unit fluctuates and enters the load holding state again to re-optimize.

[0037] In the above embodiments, the present application is significantly different from the liquid level control and database experience value control in the prior art in terms of its dynamic, intelligent and adaptive nature. Liquid level control and database experience value control are usually based on preset values ​​under fixed working conditions and cannot adapt to dynamic changes in operating conditions. However, the present solution significantly improves the operating efficiency and stability of the air-conditioning unit under different working conditions by real-time monitoring of the unit's operating status, dynamically adjusting the throttling device opening, and actively searching for the optimal operating point.

[0038] Through this embodiment, first, the unit operation data is obtained, and whether the air-conditioning unit is in a load holding state is determined at least based on the unit operation data. The load holding state is a unit operation state in which the fluctuation of the unit operation data is less than the corresponding threshold value; then, when the air-conditioning unit is in the load holding state, the opening of the throttling device of the air-conditioning unit is traversed until the target opening corresponding to the maximum value of the unit performance coefficient is determined; finally, the opening of the throttling device is adjusted to the target opening, and the target opening is maintained to control the operation of the air-conditioning unit. The present application can automatically find the optimal throttling device opening when the air-conditioning unit is in a load holding state by monitoring the unit operation data in real time and adjusting the opening of the throttling device to maximize the unit performance coefficient, thereby solving the problem that the liquid level control and database experience control methods in the prior art cannot ensure that the operation state of the throttling device of the unit is optimal within the full range of operating conditions, resulting in reduced energy efficiency and increased energy consumption.

[0039] In order to determine the target opening, in an optional implementation, the step S202 includes:

[0040] Step S2021, obtaining the current opening of the throttling device to obtain a first opening, taking the first opening as a reference, adjusting the opening of the throttling device according to a preset number of steps to traverse all openings of the throttling device, and recording the unit performance coefficient corresponding to each opening to obtain a target performance group;

[0041] Specifically, first, the opening of the throttling device at the current moment is read and recorded as the first opening. Then, taking the above first opening as the starting point, the opening of the throttling device is adjusted according to a preset number of steps. By increasing and decreasing the opening of the throttling device, all possible openings are traversed, and the unit performance coefficient corresponding to each opening is calculated, so as to subsequently select the target opening.

[0042] Step S2022: determine the opening corresponding to the maximum value of the unit performance coefficient in the target performance group as the target opening.

[0043] The unit performance coefficient and the corresponding opening recorded in the process of increasing and decreasing the throttling device opening are analyzed, and the opening corresponding to the maximum value of the unit performance coefficient is identified and determined as the above-mentioned target opening.

[0044] In the above embodiment, compared with traditional liquid level control or database experience value control, the technical solution realizes adaptive optimization control by dynamically adjusting the opening of the throttling device and real-time feedback of performance coefficient changes. It can dynamically adapt to changes in the operating conditions of the air-conditioning unit, avoids the problems of single control objectives and insufficient model calculation accuracy, and significantly improves the stability and energy efficiency of the air-conditioning unit operation.

[0045] Furthermore, in order to improve the optimization speed of the optimization process, the present application is configured to perform optimization with the above-mentioned preset number of steps, that is, the opening interval of the throttling device between two adjacent calculations is a preset number of steps (in one embodiment, it can be 5%), thereby avoiding traversing all openings, resulting in lower optimization and adjustment efficiency.

[0046] In order to further shorten the time of the optimization process and improve the efficiency of the working condition adjustment, in an optional implementation, the above step S2021 includes:

[0047] Step S20211, taking the first opening as a reference, increasing the preset number of steps at each preset time interval and recording the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is fully opened, thereby obtaining a first performance group;

[0048] Specifically, based on the first opening, the unit performance coefficient at the current moment is calculated, and then the opening of the throttling device is gradually increased with the preset number of steps and the preset duration, and the unit performance coefficient is recorded to obtain the first performance group. And because the unit performance coefficient and the throttling device opening are in a linear relationship, the present application is set to stop traversing when the unit performance coefficient decreases during the process of increasing the opening, so as to improve the efficiency of optimization and reduce time consumption.

[0049] For example: set the throttling device action cycle T1 (i.e. the above-mentioned preset duration, which can be 5 minutes) and the action variable K (i.e. the above-mentioned preset number of steps, which can be 5%). In the intelligent optimization mode, the opening of the throttling device is gradually increased with the above-mentioned action variable. For example, after the first action cycle, the throttling device opening increases from 40% to 45%, and the current unit performance coefficient is calculated by detection. Repeat the above process, increase the opening by 5% after each action cycle, and record the corresponding unit performance coefficient at the same time, until it is found that the unit performance coefficient begins to decrease after two consecutive adjustments, or the throttling device is fully opened (100%). When the throttling device opening increases from 50% to 55%, the unit performance coefficient decreases from 2.5 to 2.4, and the opening will stop increasing at this time. All unit performance parameters calculated during the adjustment process are determined as the above-mentioned first performance group.

[0050] Step S20212, adjusting the opening of the throttling device to the first opening;

[0051] Specifically, the opening is restored to the first opening degree to prepare for the next opening degree reduction process.

[0052] Step S20213, taking the first opening as a reference, reducing the preset number of steps at each preset time interval and recording the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is completely closed, thereby obtaining a second performance group;

[0053] Specifically, based on the first opening, the opening of the throttling device is gradually reduced with the preset number of steps and the preset duration, and the unit performance coefficient is recorded to obtain the second performance group. Similarly, when the unit performance coefficient decreases during the process of reducing the opening, the traversal is stopped to improve the efficiency of the optimization and reduce time consumption.

[0054] For example: in the intelligent optimization mode, the opening of the throttling device is gradually reduced with the above-mentioned action variables. For example, after the first action cycle, the opening of the throttling device is reduced from 40% to 35%, and the current unit performance coefficient is calculated by detection. Repeat the above process, reduce the opening by 5% after each action cycle, and record the corresponding unit performance coefficient at the same time, until it is found that the unit performance coefficient begins to decrease after two consecutive adjustments, or the throttling device is completely closed (0%), and all unit performance parameters calculated during the adjustment process are determined as the above-mentioned second performance group.

[0055] Step S20214: determine the target performance group based on the first performance group and the second performance group.

[0056] Specifically, the first performance group and the second performance group are integrated into one parameter group to obtain the target performance group, that is, to obtain the performance coefficients of all units recorded in the optimization process.

[0057] In the above embodiment, the present application is based on the linear relationship between the unit performance coefficient and the opening of the throttling device, and is set with the first opening as the benchmark. In the process of increasing or decreasing the opening, when the unit performance coefficient corresponding to the opening decreases, the adjustment is stopped to reduce the length of the traversed interval and improve the efficiency of optimization.

[0058] In a specific embodiment, in order to improve the accuracy of optimization, the preset number of steps can be further reduced (for example, from 5% to 2%), and the opening interval corresponding to the start and end times of the last action cycle in the process of increasing or decreasing the opening can be re-traversed with the updated preset number of steps to determine a more accurate target opening.

[0059] In order to ensure that the air-conditioning unit is in a load-maintaining state, in an optional implementation manner, the above step S201 includes:

[0060] Step S2011, when the outlet water temperature fluctuation of the air-conditioning unit is less than a first threshold, determining that the air-conditioning unit meets a first preset condition;

[0061] In the specific implementation, the outlet water temperature fluctuation monitoring: first, continuously monitor the outlet water temperature of the air-conditioning unit. If the outlet water temperature fluctuation range is within ±0.5°C (for example, the temperature fluctuates from 12°C to 12.4°C and then returns to 11.8°C), it is determined that the air-conditioning unit meets the first preset condition, that is, the outlet water temperature fluctuation is less than the first threshold (±0.5°C in this case).

[0062] Step S2012, when the operating frequency fluctuation of the air-conditioning unit is less than the second threshold, determining that the air-conditioning unit meets the second preset condition;

[0063] In the specific implementation, operating frequency fluctuation monitoring: At the same time, the system monitors the fluctuation of the unit's operating frequency. If the fluctuation range of the operating frequency is within ±2Hz (for example, the frequency fluctuates from 50Hz to 52Hz and then returns to 49Hz), it is determined that the air-conditioning unit meets the second preset condition, that is, the operating frequency fluctuation is less than the second threshold (±2Hz in this case).

[0064] Step S2013, when the opening fluctuation of the compressor guide vane of the air-conditioning unit is less than the third threshold value, determining that the air-conditioning unit meets the third preset condition;

[0065] In a specific implementation, compressor guide vane opening fluctuation monitoring: the system also monitors the fluctuation of the compressor guide vane opening. If the fluctuation range of the guide vane opening is within ±2% (for example, the opening fluctuates from 50% to 52% and then returns to 49%), it is determined that the air-conditioning unit meets the third preset condition, that is, the compressor guide vane opening fluctuation is less than the third threshold (±2% in this case).

[0066] Step S2014: When the first preset condition, the second preset condition and the third preset condition are all satisfied, it is determined that the air-conditioning unit is in the load holding state.

[0067] In the specific implementation, the fluctuations of three key parameters - water outlet temperature, operating frequency and compressor guide vane opening - are monitored and compared with the preset first, second and third thresholds respectively. If the fluctuations of these three parameters remain within the set thresholds, it is determined that the air-conditioning unit is in a load holding state.

[0068] In the above embodiment, the outlet water temperature monitoring can reflect whether the cooling or heating capacity of the air-conditioning unit is stable. Large fluctuations indicate that the system cannot maintain the current steady state, and the air-conditioning unit is in the process of changing the set parameters. For example, when the cooling demand suddenly increases, the outlet water temperature will suddenly rise, and the compressor operating frequency fluctuates, which directly determines the cooling and heating capacity of the air-conditioning. Large fluctuations in frequency mean that the system is adjusting to adapt to load changes, and the fluctuations in the opening of the compressor guide vanes directly affect the flow and pressure of the refrigerant, thereby affecting the cooling or heating efficiency of the air-conditioning unit. The load holding state can ensure the continuity of the refrigerant cycle and energy efficiency optimization. The use of the above three key parameters to judge the load holding state can reflect the operating state of the air-conditioning from multiple dimensions, improve the accuracy of the judgment, and achieve a comprehensive and accurate assessment of whether the air-conditioning unit is in a load holding state.

[0069] In order to obtain the above unit performance coefficient, in an optional implementation, the above step S2021 further includes:

[0070] Step S20215, when the air conditioning unit is in cooling mode, calculating the cooling capacity of the unit by using a heat power formula based on a first water flow rate and a first temperature difference, wherein the first water flow rate is the water flow rate of the evaporator of the air conditioning unit, and the first temperature difference is the inlet and outlet water temperature difference of the evaporator;

[0071] Specifically, the cooling capacity of the unit is usually calculated by detecting the temperature difference and flow rate of the inlet and outlet water of the evaporator, based on the thermal power formula: unit cooling capacity = water flow rate × specific heat capacity of water × temperature difference. Assuming that the specific heat capacity of water is 4.18kJ / (kg·℃), the first water flow rate is 5000 liters / hour, and the first temperature difference is 5℃, the cooling capacity of the unit at the current moment can be calculated by the following steps: Since 1 liter of water is approximately equal to 1 kilogram, the water flow rate of 5000 liters / hour is 5000 kilograms / hour. Convert the mass flow rate to flow rate per second: 5000 kilograms / hour = 5000 / 3600 kilograms / second ≈ 1.39 kilograms / second. According to the thermal power formula, calculate the cooling capacity: cooling capacity = 1.39 kilograms / second × 4.18kJ / (kg·℃) × 5℃ = 28.34kJ / s ≈ 28.34kW.

[0072] Step S20216, calculating the ratio of the cooling capacity of the unit to the power consumption of the unit to obtain the coefficient of performance of the unit;

[0073] In a specific implementation, when the air conditioner unit is in cooling mode, based on the current cooling capacity of the air conditioner unit (e.g., 100kW) and the power consumption of the unit (e.g., 80kW), the unit performance coefficient is calculated as follows: unit performance coefficient = unit cooling capacity / unit operating load = 100kW / 80kW = 1.25. This value reflects the cooling capacity corresponding to each unit operating load under the current operating conditions. The higher the value, the higher the operating efficiency of the air conditioner unit.

[0074] Step S20217, when the air conditioning unit is in heating mode, the heating amount of the unit is calculated by a heat power formula based on a second water flow rate and a second temperature difference, wherein the second water flow rate is the water flow rate of the condenser of the air conditioning unit, and the second temperature difference is the inlet and outlet water temperature difference of the condenser;

[0075] Specifically, based on the thermal power formula: heating capacity = water flow rate × specific heat of water × temperature difference. Assuming that the specific heat capacity of water is 4.18kJ / (kg·℃), the first water flow rate is 6000 liters / hour, and the first temperature difference is 7℃, the heating capacity of the unit at the current moment can be calculated by the following steps: Since 1 liter of water is approximately equal to 1 kilogram, a water flow rate of 6000 liters / hour is 6000 kilograms / hour. Convert the mass flow rate to flow rate per second: 6000 kilograms / hour = 6000 / 3600 kilograms / second ≈ 1.67 kilograms / second. According to the thermal power formula, calculate the heating capacity: heating capacity = 1.67 kilograms / second × 4.18kJ / (kg·℃) × 7℃ ≈ 49.96kJ / s ≈ 49.96kW.

[0076] Step S20218, calculating the ratio of the heating amount of the unit to the power consumption of the unit to obtain the performance coefficient of the unit.

[0077] Specifically, in a specific implementation, when the air conditioning unit is in heating mode, based on the current unit heating capacity (e.g., 150kW) and the unit operating load (e.g., 100kW), the unit performance coefficient is calculated to include: unit performance coefficient = unit heating capacity / unit operating load = 150kW / 100kW = 1.5. Similar to the cooling mode, a higher performance coefficient means that in the heating mode, the heating capacity corresponding to each unit unit operating load is greater, and the air conditioning unit operates more efficiently.

[0078] In the above embodiment, the cooling or heating capacity of the air-conditioning unit is quantified as a numerical index through the unit performance coefficient, and then through the size relationship between the numerical indicators, it can be determined whether the opening of the throttling device is the optimal opening, which provides strong support for the optimization process of the intelligent optimization mode.

[0079] In order to obtain the water flow of the evaporator or the condenser, in an optional implementation, the above step S20215 or step S20217 includes:

[0080] Obtaining a first pressure difference or a second pressure difference, wherein the first pressure difference is the inlet and outlet water pressure difference of the evaporator, and the second pressure difference is the inlet and outlet water pressure difference of the condenser;

[0081] Specifically, the measurement of the water flow rate of the evaporator inlet and outlet includes: when the air conditioning unit is running, firstly using a pressure difference sensor installed on the evaporator or condenser water pipe to monitor the first pressure difference or the second pressure difference.

[0082] Substitute the above-mentioned first pressure difference or the above-mentioned second pressure difference into the first preset formula to obtain the above-mentioned first water flow rate or the above-mentioned second water flow rate. The above-mentioned first preset formula is obtained by fitting the inlet and outlet water pressure difference and water flow rate of the above-mentioned evaporator or the above-mentioned condenser according to the historical operation data of the above-mentioned air-conditioning unit.

[0083] Specifically, the present application sets up fitting through experiments to determine the expression of the linear fitting relationship between water flow and pressure difference, that is, the above-mentioned first preset formula, and then after monitoring the above-mentioned first pressure difference or the second pressure difference, the corresponding above-mentioned first water flow or second water flow can be determined by the pressure difference.

[0084] In a specific implementation, taking the acquisition of the above-mentioned first water flow rate as an example, when the air conditioning unit is running, first, read the value of the pressure sensor at the water inlet of the evaporator to obtain the first pressure (for example, 10 bar); then read the value of the pressure sensor at the water outlet to obtain the second pressure (for example, 8 bar). The system calculates the difference between the first pressure and the second pressure, that is, the first pressure difference (10 bar-8 bar=2 bar). Substitute the above-mentioned first pressure difference into the preset formula to obtain the above-mentioned first water flow rate: M=AX^2+BX+C, where M is the above-mentioned first water flow rate, X is the above-mentioned pressure difference, and A, B and C are fitting coefficients. For example, the first pressure difference of 2 bar is substituted into the preset formula to calculate the first water flow rate: Assuming that the formula parameters obtained by fitting historical data are A=0.5, B=-5, C=100 (these parameters are determined according to the specific unit), the first water flow rate M=0.5×(2)^2-5×2+100=100-10+2=92 liters / minute.

[0085] In the above embodiment, the present application is configured to calculate the water flow by fitting, replacing the monitoring of the water flow by a flow meter in the prior art, saving the cost of the overall structure of the air-conditioning unit and the cost of modifying the air-conditioning unit, thereby reducing costs.

[0086] In order to ensure stable operation of the air conditioning unit in a non-load holding state, in an optional implementation manner, after obtaining the unit operation data, the method further includes:

[0087] Step S301, when the air conditioning unit is not in the load holding state, obtaining a first liquid level or a second liquid level, wherein the first liquid level is a condenser liquid level and the second liquid level is an evaporator liquid level;

[0088] Specifically, if the air-conditioning unit is not in the load maintenance state, the liquid level of the corresponding component is obtained based on the current air-conditioning operation mode, wherein if the air-conditioning unit is in cooling mode, the first liquid level is obtained, and if the air-conditioning unit is in heating mode, the second liquid level is obtained.

[0089] Step S302, when the first liquid level or the second liquid level is less than a first threshold, increasing the opening of the throttling device based on a deviation between the first liquid level or the second liquid level and the first threshold;

[0090] Specifically, after obtaining the liquid level at the current moment, the optimal liquid level under the operating conditions is determined based on the operating conditions at the current moment, that is, the above-mentioned first threshold. If the above-mentioned first liquid level or the above-mentioned second liquid level is less than the first threshold, then based on the deviation between the current liquid level and the optimal liquid level, the opening of the above-mentioned throttling device is increased.

[0091] Step S303, when the first liquid level or the second liquid level is greater than a first threshold, reducing the opening of the throttling device based on a deviation between the first liquid level or the second liquid level and the first threshold.

[0092] Specifically, after obtaining the liquid level at the current moment, the optimal liquid level under the operating conditions is determined based on the operating conditions at the current moment, that is, the above-mentioned first threshold. If the above-mentioned first liquid level or the above-mentioned second liquid level is greater than the first threshold, then based on the deviation between the current liquid level and the optimal liquid level, the opening of the above-mentioned throttling device is reduced.

[0093] If the air-conditioning unit is not in the load-maintaining state, the intelligent optimization control of the present application will be deviated, resulting in the final optimization result not being applicable to the changed working conditions. Therefore, in addition to the intelligent optimization control, the present application also provides a liquid level control method to achieve stable operation of the air-conditioning unit during the dynamic change of the operating state of the air-conditioning unit.

[0094] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0095] The embodiment of the present application also provides an optimization control device for an air-conditioning unit. It should be noted that the optimization control device for an air-conditioning unit in the embodiment of the present application can be used to execute the optimization control method for an air-conditioning unit provided in the embodiment of the present application. The device is used to implement the above-mentioned embodiments and preferred implementation modes, and the descriptions that have been made will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware for a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation of hardware, or a combination of software and hardware, is also possible and conceivable.

[0096] The following is an introduction to the optimization control device for an air-conditioning unit provided in an embodiment of the present application.

[0097] Figure 3 is a structural block diagram of an optimal control device for an air conditioning unit according to an embodiment of the present application. Figure 3 As shown, the device comprises:

[0098] A first acquisition unit 10 is used to acquire unit operation data, and determine whether the air conditioning unit is in a load holding state at least based on the unit operation data, wherein the load holding state is a unit operation state in which a fluctuation of the unit operation data is less than a corresponding threshold value;

[0099] Specifically, by acquiring the above-mentioned unit operation data in real time, it is determined whether the air-conditioning unit is in a load holding state, that is, the fluctuation of the unit operation data is less than a preset threshold.

[0100] In a specific implementation, the above-mentioned unit operation data include, but are not limited to, key parameters such as chilled water outlet temperature, compressor operating frequency, and compressor guide vane opening. Corresponding thresholds are set for different unit operation data to determine whether the air-conditioning unit is in a stable operating state, that is, the above-mentioned load holding state. It can be understood that the above-mentioned control is used to ensure the stability of the operating conditions of the air-conditioning unit, avoiding optimization during the change of operating conditions, resulting in the optimization result not being applicable to the changed operating conditions, and causing the target operating condition to be not the optimal operating condition.

[0101] The first control unit 20 is used to traverse the opening of the throttling device of the air-conditioning unit when the air-conditioning unit is in the load holding state until a target opening corresponding to the maximum value of the unit performance coefficient is determined;

[0102] Specifically, after confirming that the air-conditioning unit is in a load-holding state, the system automatically adjusts the throttling device opening of the air-conditioning unit, and gradually seeks the target opening that can maximize the unit's coefficient of performance. The unit's coefficient of performance is determined by the ratio of the air-conditioning unit's cooling capacity or heating capacity to the operating load.

[0103] It can be understood that the present application is configured to traverse all possible openings of the throttling device under the stable operating conditions at the current moment, and to measure the performance of the air-conditioning unit at different openings by using the unit performance coefficient as an indicator, and to take the opening with the maximum value of the unit performance coefficient as the target opening, thereby realizing the optimization of the throttling device opening under all operating conditions.

[0104] The second control unit 30 is used to adjust the opening of the throttling device to the target opening, and maintain the target opening to control the operation of the air-conditioning unit.

[0105] Specifically, after finding the optimal opening, the system maintains the throttling device opening at the target opening to achieve efficient and stable operation of the air-conditioning unit until the operating state of the air-conditioning unit fluctuates and enters the load holding state again to re-optimize.

[0106] In the above embodiments, the present application is significantly different from the liquid level control and database experience value control in the prior art in terms of its dynamic, intelligent and adaptive nature. Liquid level control and database experience value control are usually based on preset values ​​under fixed working conditions and cannot adapt to dynamic changes in operating conditions. However, the present solution significantly improves the operating efficiency and stability of the air-conditioning unit under different working conditions by real-time monitoring of the unit's operating status, dynamically adjusting the throttling device opening, and actively searching for the optimal operating point.

[0107] Through this embodiment, the first acquisition unit acquires the unit operation data, and determines whether the air-conditioning unit is in a load holding state at least based on the unit operation data. The load holding state is a unit operation state in which the fluctuation of the unit operation data is less than the corresponding threshold value; the first control unit traverses the opening of the throttling device of the air-conditioning unit when the air-conditioning unit is in the load holding state until the target opening corresponding to the maximum value of the unit performance coefficient is determined; the second control unit adjusts the opening of the throttling device to the target opening, and maintains the target opening to control the operation of the air-conditioning unit. The present application can automatically find the optimal throttling device opening when the air-conditioning unit is in a load holding state by monitoring the unit operation data in real time and adjusting the opening of the throttling device to maximize the unit performance coefficient, thereby solving the problem that the liquid level control and database experience control methods in the prior art cannot ensure the optimal operation state of the throttling device of the unit within the full range of operating conditions, resulting in reduced energy efficiency and increased energy consumption.

[0108] In order to determine the target opening, in an optional implementation, the first control unit includes:

[0109] A first acquisition module is used to acquire the opening of the throttling device at the current moment to obtain a first opening, and to adjust the opening of the throttling device according to a preset number of steps based on the first opening to traverse all openings of the throttling device, and to record the unit performance coefficient corresponding to each opening to obtain a target performance group;

[0110] Specifically, first, the opening of the throttling device at the current moment is read and recorded as the first opening. Then, taking the above first opening as the starting point, the opening of the throttling device is adjusted according to a preset number of steps. By increasing and decreasing the opening of the throttling device, all possible openings are traversed, and the unit performance coefficient corresponding to each opening is calculated, so as to subsequently select the target opening.

[0111] The first determination module is used to determine the opening corresponding to the maximum value of the unit performance coefficient in the target performance group as the target opening.

[0112] The unit performance coefficient and the corresponding opening recorded in the process of increasing and decreasing the throttling device opening are analyzed, and the opening corresponding to the maximum value of the unit performance coefficient is identified and determined as the above-mentioned target opening.

[0113] In the above embodiment, compared with traditional liquid level control or database experience value control, the technical solution realizes adaptive optimization control by dynamically adjusting the opening of the throttling device and real-time feedback of performance coefficient changes. It can dynamically adapt to changes in the operating conditions of the air-conditioning unit, avoids the problems of single control objectives and insufficient model calculation accuracy, and significantly improves the stability and energy efficiency of the air-conditioning unit operation.

[0114] Furthermore, in order to improve the optimization speed of the optimization process, the present application is configured to perform optimization with the above-mentioned preset number of steps, that is, the opening interval of the throttling device between two adjacent calculations is a preset number of steps (in one embodiment, it can be 5%), thereby avoiding traversing all openings, resulting in lower optimization and adjustment efficiency.

[0115] In order to further shorten the time of the optimization process and improve the efficiency of the working condition adjustment, in an optional implementation manner, the first acquisition module includes:

[0116] A first control submodule is used to increase the preset number of steps at each preset time interval based on the first opening and record the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is fully opened, thereby obtaining a first performance group;

[0117] Specifically, based on the first opening, the unit performance coefficient at the current moment is calculated, and then the opening of the throttling device is gradually increased with the preset number of steps and the preset duration, and the unit performance coefficient is recorded to obtain the first performance group. And because the unit performance coefficient and the throttling device opening are in a linear relationship, the present application is set to stop traversing when the unit performance coefficient decreases during the process of increasing the opening, so as to improve the efficiency of optimization and reduce time consumption.

[0118] For example: set the throttling device action cycle T1 (i.e. the above-mentioned preset duration, which can be 5 minutes) and the action variable K (i.e. the above-mentioned preset number of steps, which can be 5%). In the intelligent optimization mode, the opening of the throttling device is gradually increased with the above-mentioned action variable. For example, after the first action cycle, the throttling device opening increases from 40% to 45%, and the current unit performance coefficient is calculated by detection. Repeat the above process, increase the opening by 5% after each action cycle, and record the corresponding unit performance coefficient at the same time, until it is found that the unit performance coefficient begins to decrease after two consecutive adjustments, or the throttling device is fully opened (100%). When the throttling device opening increases from 50% to 55%, the unit performance coefficient decreases from 2.5 to 2.4, and the opening will stop increasing at this time. All unit performance parameters calculated during the adjustment process are determined as the above-mentioned first performance group.

[0119] A first determining submodule, used for adjusting the opening of the throttling device to the first opening;

[0120] Specifically, the opening is restored to the first opening degree to prepare for the next opening degree reduction process.

[0121] A second control submodule is used for reducing the preset number of steps at each preset time interval based on the first opening and recording the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is completely closed, thereby obtaining a second performance group;

[0122] Specifically, based on the first opening, the opening of the throttling device is gradually reduced with the preset number of steps and the preset duration, and the unit performance coefficient is recorded to obtain the second performance group. Similarly, when the unit performance coefficient decreases during the process of reducing the opening, the traversal is stopped to improve the efficiency of the optimization and reduce time consumption.

[0123] For example: in the intelligent optimization mode, the opening of the throttling device is gradually reduced with the above-mentioned action variables. For example, after the first action cycle, the opening of the throttling device is reduced from 40% to 35%, and the current unit performance coefficient is calculated by detection. Repeat the above process, reduce the opening by 5% after each action cycle, and record the corresponding unit performance coefficient at the same time, until it is found that the unit performance coefficient begins to decrease after two consecutive adjustments, or the throttling device is completely closed (0%), and all unit performance parameters calculated during the adjustment process are determined as the above-mentioned second performance group.

[0124] The second determining submodule is used to determine the target performance group according to the first performance group and the second performance group.

[0125] Specifically, the first performance group and the second performance group are integrated into one parameter group to obtain the target performance group, that is, to obtain the performance coefficients of all units recorded in the optimization process.

[0126] In the above embodiment, the present application is based on the linear relationship between the unit performance coefficient and the opening of the throttling device, and is set with the first opening as the benchmark. In the process of increasing or decreasing the opening, when the unit performance coefficient corresponding to the opening decreases, the adjustment is stopped to reduce the length of the traversed interval and improve the efficiency of optimization.

[0127] In a specific embodiment, in order to improve the accuracy of optimization, the preset number of steps can be further reduced (for example, from 5% to 2%), and the opening interval corresponding to the start and end times of the last action cycle in the process of increasing or decreasing the opening can be re-traversed with the updated preset number of steps to determine a more accurate target opening.

[0128] In order to ensure that the air-conditioning unit is in a load-maintaining state, in an optional implementation manner, the first acquisition unit includes:

[0129] A second determination module, configured to determine that the air-conditioning unit meets a first preset condition when the outlet water temperature fluctuation of the air-conditioning unit is less than a first threshold;

[0130] In the specific implementation, the outlet water temperature fluctuation monitoring: first, continuously monitor the outlet water temperature of the air-conditioning unit. If the outlet water temperature fluctuation range is within ±0.5°C (for example, the temperature fluctuates from 12°C to 12.4°C and then returns to 11.8°C), it is determined that the air-conditioning unit meets the first preset condition, that is, the outlet water temperature fluctuation is less than the first threshold (±0.5°C in this case).

[0131] A third determination module, configured to determine that the air-conditioning unit meets a second preset condition when the operating frequency fluctuation of the air-conditioning unit is less than a second threshold;

[0132] In the specific implementation, operating frequency fluctuation monitoring: At the same time, the system monitors the fluctuation of the unit's operating frequency. If the fluctuation range of the operating frequency is within ±2Hz (for example, the frequency fluctuates from 50Hz to 52Hz and then returns to 49Hz), it is determined that the air-conditioning unit meets the second preset condition, that is, the operating frequency fluctuation is less than the second threshold (±2Hz in this case).

[0133] a fourth determination module, configured to determine that the air-conditioning unit satisfies a third preset condition when the opening fluctuation of the compressor guide vane of the air-conditioning unit is less than a third threshold;

[0134] In a specific implementation, compressor guide vane opening fluctuation monitoring: the system also monitors the fluctuation of the compressor guide vane opening. If the fluctuation range of the guide vane opening is within ±2% (for example, the opening fluctuates from 50% to 52% and then returns to 49%), it is determined that the air-conditioning unit meets the third preset condition, that is, the compressor guide vane opening fluctuation is less than the third threshold (±2% in this case).

[0135] The fifth determination module is used to determine that the air-conditioning unit is in the load holding state when the first preset condition, the second preset condition and the third preset condition are all satisfied.

[0136] In the specific implementation, the fluctuations of three key parameters - water outlet temperature, operating frequency and compressor guide vane opening - are monitored and compared with the preset first, second and third thresholds respectively. If the fluctuations of these three parameters remain within the set thresholds, it is determined that the air-conditioning unit is in a load holding state.

[0137] In the above embodiment, the outlet water temperature monitoring can reflect whether the cooling or heating capacity of the air-conditioning unit is stable. Large fluctuations indicate that the system cannot maintain the current steady state, and the air-conditioning unit is in the process of changing the set parameters. For example, when the cooling demand suddenly increases, the outlet water temperature will suddenly rise, and the compressor operating frequency fluctuates, which directly determines the cooling and heating capacity of the air-conditioning. Large fluctuations in frequency mean that the system is adjusting to adapt to load changes, and the fluctuations in the opening of the compressor guide vanes directly affect the flow and pressure of the refrigerant, thereby affecting the cooling or heating efficiency of the air-conditioning unit. The load holding state can ensure the continuity of the refrigerant cycle and energy efficiency optimization. The use of the above three key parameters to judge the load holding state can reflect the operating state of the air-conditioning from multiple dimensions, improve the accuracy of the judgment, and achieve a comprehensive and accurate assessment of whether the air-conditioning unit is in a load holding state.

[0138] In order to obtain the above unit performance coefficient, in an optional implementation manner, the above first acquisition module further includes:

[0139] A first calculation submodule is used to calculate the cooling capacity of the air-conditioning unit by a heat power formula based on a first water flow rate and a first temperature difference when the air-conditioning unit is in a cooling mode, wherein the first water flow rate is the water flow rate of the evaporator of the air-conditioning unit, and the first temperature difference is the inlet and outlet water temperature difference of the evaporator;

[0140] Specifically, the cooling capacity of the unit is usually calculated by detecting the temperature difference and flow rate of the inlet and outlet water of the evaporator, based on the thermal power formula: unit cooling capacity = water flow rate × specific heat capacity of water × temperature difference. Assuming that the specific heat capacity of water is 4.18kJ / (kg·℃), the first water flow rate is 5000 liters / hour, and the first temperature difference is 5℃, the cooling capacity of the unit at the current moment can be calculated by the following steps: Since 1 liter of water is approximately equal to 1 kilogram, the water flow rate of 5000 liters / hour is 5000 kilograms / hour. Convert the mass flow rate to flow rate per second: 5000 kilograms / hour = 5000 / 3600 kilograms / second ≈ 1.39 kilograms / second. According to the thermal power formula, calculate the cooling capacity: cooling capacity = 1.39 kilograms / second × 4.18kJ / (kg·℃) × 5℃ = 28.34kJ / s ≈ 28.34kW.

[0141] The second calculation submodule is used to calculate the ratio of the cooling capacity of the unit to the power consumption of the unit to obtain the performance coefficient of the unit;

[0142] In a specific implementation, when the air conditioner unit is in cooling mode, based on the current cooling capacity of the air conditioner unit (e.g., 100kW) and the power consumption of the unit (e.g., 80kW), the unit performance coefficient is calculated as follows: unit performance coefficient = unit cooling capacity / unit operating load = 100kW / 80kW = 1.25. This value reflects the cooling capacity corresponding to each unit operating load under the current operating conditions. The higher the value, the higher the operating efficiency of the air conditioner unit.

[0143] A third calculation submodule is used to calculate the heating amount of the air-conditioning unit by a heat power formula based on a second water flow rate and a second temperature difference when the air-conditioning unit is in a heating mode, wherein the second water flow rate is the water flow rate of the condenser of the air-conditioning unit, and the second temperature difference is the inlet and outlet water temperature difference of the condenser;

[0144] Specifically, based on the thermal power formula: heating capacity = water flow rate × specific heat of water × temperature difference. Assuming that the specific heat capacity of water is 4.18kJ / (kg·℃), the first water flow rate is 6000 liters / hour, and the first temperature difference is 7℃, the heating capacity of the unit at the current moment can be calculated by the following steps: Since 1 liter of water is approximately equal to 1 kilogram, a water flow rate of 6000 liters / hour is 6000 kilograms / hour. Convert the mass flow rate to flow rate per second: 6000 kilograms / hour = 6000 / 3600 kilograms / second ≈ 1.67 kilograms / second. According to the thermal power formula, calculate the heating capacity: heating capacity = 1.67 kilograms / second × 4.18kJ / (kg·℃) × 7℃ ≈ 49.96kJ / s ≈ 49.96kW.

[0145] The fourth calculation submodule is used to calculate the ratio of the heating amount of the above-mentioned unit to the power consumption of the above-mentioned unit to obtain the performance coefficient of the above-mentioned unit.

[0146] Specifically, in a specific implementation, when the air conditioning unit is in heating mode, based on the current unit heating capacity (e.g., 150kW) and the unit operating load (e.g., 100kW), the unit performance coefficient is calculated to include: unit performance coefficient = unit heating capacity / unit operating load = 150kW / 100kW = 1.5. Similar to the cooling mode, a higher performance coefficient means that in the heating mode, the heating capacity corresponding to each unit unit operating load is greater, and the air conditioning unit operates more efficiently.

[0147] In the above embodiment, the cooling or heating capacity of the air-conditioning unit is quantified as a numerical index through the unit performance coefficient, and then through the size relationship between the numerical indicators, it can be determined whether the opening of the throttling device is the optimal opening, which provides strong support for the optimization process of the intelligent optimization mode.

[0148] In order to obtain the water flow of the evaporator or the condenser, in an optional implementation, the first calculation submodule or the third calculation submodule further includes:

[0149] An acquisition submodule, used for acquiring a first pressure difference or a second pressure difference, wherein the first pressure difference is the inlet and outlet water pressure difference of the evaporator, and the second pressure difference is the inlet and outlet water pressure difference of the condenser;

[0150] Specifically, the measurement of the water flow rate of the evaporator inlet and outlet includes: when the air conditioning unit is running, firstly using a pressure difference sensor installed on the evaporator or condenser water pipe to monitor the first pressure difference or the second pressure difference.

[0151] The fifth calculation submodule is used to substitute the above-mentioned first pressure difference or the above-mentioned second pressure difference into the first preset formula to obtain the above-mentioned first water flow rate or the above-mentioned second water flow rate, and the above-mentioned first preset formula is obtained by fitting the inlet and outlet water pressure difference and water flow rate of the above-mentioned evaporator or the above-mentioned condenser according to the historical operation data of the above-mentioned air-conditioning unit.

[0152] Specifically, the present application sets up fitting through experiments to determine the expression of the linear fitting relationship between water flow and pressure difference, that is, the above-mentioned first preset formula, and then after monitoring the above-mentioned first pressure difference or the second pressure difference, the corresponding above-mentioned first water flow or second water flow can be determined by the pressure difference.

[0153] In a specific implementation, taking the acquisition of the above-mentioned first water flow rate as an example, when the air conditioning unit is running, first, read the value of the pressure sensor at the water inlet of the evaporator to obtain the first pressure (for example, 10 bar); then read the value of the pressure sensor at the water outlet to obtain the second pressure (for example, 8 bar). The system calculates the difference between the first pressure and the second pressure, that is, the first pressure difference (10 bar-8 bar=2 bar). Substitute the above-mentioned first pressure difference into the preset formula to obtain the above-mentioned first water flow rate: M=AX^2+BX+C, where M is the above-mentioned first water flow rate, X is the above-mentioned pressure difference, and A, B and C are fitting coefficients. For example, the first pressure difference 2 bar is substituted into the preset formula to calculate the first water flow rate: Assuming that the formula parameters obtained by fitting historical data are A=0.5, B=-5, C=100 (these parameters are determined according to the specific unit), the first water flow rate M=0.5×(2)^2-5×2+100=100-10+2=92 liters / minute.

[0154] In the above embodiment, the present application is configured to calculate the water flow by fitting, replacing the monitoring of the water flow by a flow meter in the prior art, saving the cost of the overall structure of the air-conditioning unit and the cost of modifying the air-conditioning unit, thereby reducing costs.

[0155] In order to ensure stable operation of the air conditioning unit in a non-load holding state, in an optional implementation manner, the above device further includes:

[0156] A second acquisition unit is used to acquire a first liquid level or a second liquid level after acquiring the unit operation data, when the air conditioning unit is not in the load holding state, wherein the first liquid level is a condenser liquid level and the second liquid level is an evaporator liquid level;

[0157] Specifically, if the air-conditioning unit is not in the load maintenance state, the liquid level of the corresponding component is obtained based on the current air-conditioning operation mode, wherein if the air-conditioning unit is in cooling mode, the first liquid level is obtained, and if the air-conditioning unit is in heating mode, the second liquid level is obtained.

[0158] a third control unit, configured to increase the opening of the throttling device based on a deviation of the first liquid level or the second liquid level from the first threshold value when the first liquid level or the second liquid level is less than the first threshold value;

[0159] Specifically, after obtaining the liquid level at the current moment, the optimal liquid level under the operating conditions is determined based on the operating conditions at the current moment, that is, the above-mentioned first threshold. If the above-mentioned first liquid level or the above-mentioned second liquid level is less than the first threshold, then based on the deviation between the current liquid level and the optimal liquid level, the opening of the above-mentioned throttling device is increased.

[0160] The fourth control unit is used to reduce the opening of the throttling device based on the deviation of the first liquid level or the second liquid level from the first threshold value when the first liquid level or the second liquid level is greater than the first threshold value.

[0161] Specifically, after obtaining the liquid level at the current moment, the optimal liquid level under the operating conditions is determined based on the operating conditions at the current moment, that is, the above-mentioned first threshold. If the above-mentioned first liquid level or the above-mentioned second liquid level is greater than the first threshold, then based on the deviation between the current liquid level and the optimal liquid level, the opening of the above-mentioned throttling device is reduced.

[0162] The above-mentioned optimization control device for the air conditioning unit includes a processor and a memory, and the above-mentioned first acquisition unit, the first control unit, the second control unit, etc. are all stored in the memory as program units, and the processor executes the above-mentioned program units stored in the memory to realize corresponding functions. The above-mentioned modules are all located in the same processor; or, the above-mentioned modules are located in different processors in the form of any combination.

[0163] The processor includes a kernel, which calls the corresponding program unit from the memory. One or more kernels can be set, and the energy consumption of the air conditioner can be reduced by adjusting the kernel parameters.

[0164] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0165] An embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the optimization control method for the air-conditioning unit.

[0166] An embodiment of the present invention provides a processor, and the processor is used to run a program, wherein the optimization control method of the air-conditioning unit is executed when the program is run.

[0167] An embodiment of the present invention provides an air conditioning unit, which includes a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, at least the steps of the above-mentioned optimization control method of the air conditioning unit are implemented.

[0168] The present application also provides a computer program product, which, when executed on a data processing device, is suitable for executing a program that initializes at least the steps of the above-mentioned optimal control method for the air-conditioning unit.

[0169] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0170] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0171] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0172] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0173] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0174] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0175] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0176] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tapes, disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0177] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, 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 process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0178] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0179] 1) The optimization control method for the air-conditioning unit of the present application first obtains the unit operation data, and determines whether the air-conditioning unit is in a load holding state at least based on the unit operation data. The load holding state is the unit operation state in which the fluctuation of the unit operation data is less than the corresponding threshold value; then, when the air-conditioning unit is in the load holding state, the opening of the throttling device of the air-conditioning unit is traversed until the target opening corresponding to the maximum value of the unit performance coefficient is determined; finally, the opening of the throttling device is adjusted to the target opening, and the target opening is maintained to control the operation of the air-conditioning unit. The present application can automatically find the optimal throttling device opening when the air-conditioning unit is in a load holding state by monitoring the unit operation data in real time and adjusting the opening of the throttling device to maximize the unit performance coefficient, thereby solving the problem that the liquid level control and database experience control methods in the prior art cannot ensure the optimal operation state of the throttling device of the unit within the full range of operating conditions, resulting in reduced energy efficiency and increased energy consumption.

[0180] 2) The optimization control device for the air-conditioning unit of the present application, the first acquisition unit acquires the unit operation data, and determines whether the air-conditioning unit is in a load holding state based on at least the unit operation data, the load holding state being the unit operation state in which the fluctuation of the unit operation data is less than the corresponding threshold value; the first control unit traverses the opening of the throttling device of the air-conditioning unit when the air-conditioning unit is in the load holding state until the target opening corresponding to the maximum value of the unit performance coefficient is determined; the second control unit adjusts the opening of the throttling device to the target opening, and maintains the target opening to control the operation of the air-conditioning unit. The present application can automatically find the optimal throttling device opening when the air-conditioning unit is in a load holding state by monitoring the unit operation data in real time and adjusting the opening of the throttling device to maximize the unit performance coefficient, thereby solving the problem that the liquid level control and database experience control methods in the prior art cannot ensure the optimal operation state of the throttling device of the unit within the full range of operating conditions, resulting in reduced energy efficiency and increased energy consumption.

[0181] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An optimal control method for an air conditioning unit, characterized in that: include: Acquire unit operation data, and determine whether the air conditioning unit is in a load holding state at least based on the unit operation data, wherein the load holding state is a unit operation state in which a fluctuation of the unit operation data is less than a corresponding threshold value; When the air conditioning unit is in the load holding state, traversing the opening of the throttling device of the air conditioning unit until determining a target opening corresponding to the maximum value of the unit performance coefficient; The opening of the throttling device is adjusted to the target opening, and the operation of the air-conditioning unit is controlled by maintaining the target opening.

2. The method according to claim 1, characterized in that: Traversing the openings of the throttling device of the air-conditioning unit until determining a target opening corresponding to a maximum value of the unit performance coefficient, including: Acquire the opening of the throttling device at the current moment to obtain a first opening, and adjust the opening of the throttling device according to a preset number of steps based on the first opening to traverse all openings of the throttling device, and record the unit performance coefficient corresponding to each opening to obtain a target performance group; The opening corresponding to the maximum value of the unit performance coefficient in the target performance group is determined as the target opening.

3. The method according to claim 2, characterized in that Taking the first opening as a reference, adjusting the opening of the throttling device according to a preset number of steps to traverse all the openings of the throttling device, and recording the unit performance coefficient corresponding to each opening to obtain a target performance group, including: Taking the first opening as a reference, increasing the preset number of steps at each preset time interval and recording the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is fully opened, thereby obtaining a first performance group; adjusting the opening of the throttling device to the first opening; Taking the first opening as a reference, reducing the preset number of steps at each preset time interval and recording the unit performance coefficient in real time until the unit performance coefficient decreases or the throttling device is completely closed, thereby obtaining a second performance group; The target performance group is determined according to the first performance group and the second performance group.

4. The method according to claim 2, characterized in that: Determining whether the air conditioning unit is in a load holding state based on the unit operation data includes: When the outlet water temperature fluctuation of the air-conditioning unit is less than a first threshold, determining that the air-conditioning unit meets a first preset condition; When the operating frequency fluctuation of the air-conditioning unit is less than a second threshold, determining that the air-conditioning unit meets a second preset condition; When the opening fluctuation of the compressor guide vane of the air-conditioning unit is less than a third threshold, determining that the air-conditioning unit meets a third preset condition; When the first preset condition, the second preset condition and the third preset condition are all satisfied, it is determined that the air-conditioning unit is in the load holding state.

5. The method according to claim 2, characterized in that: Record the unit performance coefficient, including: When the air-conditioning unit is in cooling mode, the cooling capacity of the unit is calculated by a heat power formula based on a first water flow rate and a first temperature difference, wherein the first water flow rate is the water flow rate of the evaporator of the air-conditioning unit, and the first temperature difference is the inlet and outlet water temperature difference of the evaporator; Calculating the ratio of the cooling capacity of the unit to the power consumption of the unit to obtain the coefficient of performance of the unit; When the air-conditioning unit is in heating mode, the heating amount of the unit is calculated by a heat power formula based on a second water flow rate and a second temperature difference, wherein the second water flow rate is the water flow rate of the condenser of the air-conditioning unit, and the second temperature difference is the inlet and outlet water temperature difference of the condenser; The ratio of the heating capacity of the unit to the power consumption of the unit is calculated to obtain the performance coefficient of the unit.

6. The method according to claim 5, characterized in that Acquiring the first water flow or acquiring the second water flow includes: Obtaining a first pressure difference or a second pressure difference, wherein the first pressure difference is the inlet and outlet water pressure difference of the evaporator, and the second pressure difference is the inlet and outlet water pressure difference of the condenser; Substituting the first pressure difference or the second pressure difference into a first preset formula to obtain the first water flow rate or the second water flow rate, the first preset formula is obtained by fitting the inlet and outlet water pressure difference and water flow rate of the evaporator or the condenser in the historical operation data of the air-conditioning unit.

7. The method according to any one of claims 1 to 6, characterized in that: After obtaining the unit operation data, the method further includes: When the air conditioning unit is not in the load holding state, obtaining a first liquid level or a second liquid level, wherein the first liquid level is a condenser liquid level and the second liquid level is an evaporator liquid level; When the first liquid level or the second liquid level is less than a first threshold, based on a deviation of the first liquid level or the second liquid level from the first threshold, increasing the opening of the throttling device; When the first liquid level or the second liquid level is greater than a first threshold, the opening of the throttling device is reduced based on a deviation of the first liquid level or the second liquid level from the first threshold.

8. An optimal control device for an air conditioning unit, characterized in that: The device comprises: A first acquisition unit, configured to acquire unit operation data, and determine whether the air-conditioning unit is in a load holding state at least based on the unit operation data, wherein the load holding state is a unit operation state in which a fluctuation of the unit operation data is less than a corresponding threshold value; a first control unit, configured to traverse the opening of the throttling device of the air-conditioning unit when the air-conditioning unit is in the load holding state until a target opening corresponding to a maximum value of the unit performance coefficient is determined; The second control unit is used to adjust the opening of the throttling device to the target opening, and maintain the target opening to control the operation of the air-conditioning unit.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method according to any one of claims 1 to 7.

10. An air conditioning unit, characterized in that: include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include methods for executing any one of claims 1 to 7.

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