Valve control method and system and MAU system

Abstract

The embodiment of the invention provides a valve control method and system and an MAU system. The valve control method comprises the steps that the current enthalpy value of air is obtained; based on the current enthalpy value and a set target enthalpy value, a PID algorithm is used for determining a current control variable used for controlling the opening degree of the valve; determining a current split-range interval corresponding to the current control variable based on the plurality of split-range intervals of the control variable; wherein the plurality of split-range intervals comprise a first split-range interval, a second split-range interval and a stop split-range interval; determining valve control information of a control valve corresponding to the current split-range interval based on the control logic corresponding to each split-range interval; wherein the control logic of the first split-range interval correspondingly controls the opening degree of the cold water valve, the control logic of the second split-range interval correspondingly controls the opening degree of the hot water valve, and the control logic of the stop split-range interval correspondingly controls the valve to stop acting. According to the valve control method, efficient and accurate control over the cold water valve and the hot water valve can be achieved, and energy waste is avoided.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of HVAC regulation, and specifically to a valve control method, system and MAU system. Background Art

[0002] In modern HVAC systems, the MAU (Make-up Air Unit) system, as one of the key devices, undertakes the important task of regulating the temperature and humidity of fresh air, especially in clean rooms, laboratories and other places with high requirements on air quality.

[0003] One of the core functions of the MAU system is to adjust the enthalpy value of the air so as to keep the air state in line with the set requirements to adapt to the working conditions of different seasons (winter, summer, transitional seasons, etc.); specifically, the cold water valve of the MAU system can control the pre-cooling coil to adjust the temperature and humidity of the air, and the cold water valve of the MAU system can control the pre-heating coil to adjust the temperature of the air. Therefore, by controlling the cold water valve and hot water valve of the MAU system, the enthalpy value of the air can be changed to achieve an air state that meets the set requirements.

[0004] However, in transitional seasons and other environments, the working conditions of the MAU system are more complicated, and the control logic of the cold water valve and the hot water valve is prone to cause the phenomenon of cold and hot hedging, resulting in reduced energy efficiency and increased operating costs. Therefore, how to provide a valve control method that can achieve efficient and accurate control of the cold water valve and the hot water valve to avoid energy waste has become a problem that technicians in this field need to solve urgently. Summary of the invention

[0005] In view of this, the embodiments of the present application provide a valve control method, system and MAU system, which can achieve efficient and accurate control of cold water valves and hot water valves to avoid energy waste.

[0006] To achieve the above objectives, the embodiments of the present application provide the following technical solutions.

[0007] In a first aspect, an embodiment of the present application provides a valve control method, comprising:

[0008] Get the current enthalpy value of air;

[0009] Based on the current enthalpy value and the set target enthalpy value, the current control variable currently used to control the valve opening is determined using the PID algorithm;

[0010] Based on a plurality of split ranges of the control variable, determining a current split range corresponding to the current control variable; wherein the plurality of split ranges include a first split range, a second split range, and a stop split range;

[0011] Based on the control logic corresponding to each sub-range interval, the valve control information of the control valve corresponding to the current sub-range interval is determined; wherein, the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop action.

[0012] Optionally, the first sub-range interval, the stop sub-range interval and the second sub-range interval are multiple sub-range intervals with continuous control variables; the control variable range of the first sub-range interval is smaller than the control variable range of the stop sub-range interval; the control variable range of the stop sub-range interval is smaller than the control variable range of the second sub-range interval.

[0013] Optionally, also include:

[0014] Determine a set reference point and a set error value of the control variable, and determine a first endpoint value and a second endpoint value corresponding to the stop split range; wherein the first endpoint value is the value of the reference point minus the error value, and the second endpoint value is the value of the reference point plus the error value;

[0015] The control variable range smaller than the stop split range is determined as the first split range; the control variable range larger than the stop split range is determined as the second split range.

[0016] Optionally, the control logic of the first sub-range interval is specifically: based on the inverse relationship between the control variable and the valve opening of the cold water valve, the valve opening of the cold water valve is controlled; wherein, when the control variable is equal to the first endpoint value, the valve opening of the cold water valve corresponds to the lower limit value of the opening;

[0017] The control logic of the second sub-range interval is specifically: based on the proportional relationship between the control variable and the valve opening of the hot water valve, the valve opening of the hot water valve is controlled; wherein, when the control variable is equal to the second endpoint value, the valve opening of the hot water valve corresponds to the lower limit value of the opening.

[0018] Optionally, the determining, based on the control logic corresponding to each sub-range interval, valve control information of the control valve corresponding to the current sub-range interval includes:

[0019] If the current sub-range interval is the first sub-range interval, based on the inverse relationship between the control variable and the valve opening of the cold water valve, determining the control opening of the cold water valve corresponding to the current control variable;

[0020] Based on the controlled opening of the cold water valve, valve control information for controlling the cold water valve is determined.

[0021] Optionally, the determining, based on the control logic corresponding to each sub-range interval, valve control information of the control valve corresponding to the current sub-range interval includes:

[0022] If the current sub-range interval is the second sub-range interval, based on the proportional relationship between the control variable and the valve opening of the hot water valve, determining the control opening of the hot water valve corresponding to the current control variable;

[0023] Based on the control opening of the hot water valve, valve control information for controlling the hot water valve is determined.

[0024] Optionally, the determining of the current control variable currently used to control the valve opening by using a PID algorithm based on the current enthalpy value and the set target enthalpy value includes:

[0025] A control deviation between a current enthalpy value and a set target enthalpy value is determined, and a PID operation and a linear conversion are performed on the control deviation to obtain a current control variable.

[0026] In a second aspect, an embodiment of the present application provides a valve control system, including:

[0027] A current control variable determination module is used to determine the current control variable currently used to control the valve opening by using a PID algorithm based on the current enthalpy value of the air and the set target enthalpy value;

[0028] The sub-range control module is used to determine the current sub-range interval corresponding to the current control variable based on multiple sub-range intervals of the control variable; wherein the multiple sub-range intervals include a first sub-range interval, a second sub-range interval and a stop sub-range interval; based on the control logic corresponding to each sub-range interval, the valve control information of the control valve corresponding to the current sub-range interval is determined; wherein the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop operating.

[0029] In a third aspect, an embodiment of the present application provides a MAU system, including:

[0030] Enthalpy sensor, used to detect the current enthalpy value of air;

[0031] A cold water valve and a pre-cooling coil, wherein the pre-cooling coil is cooled by the cold water valve to reduce the enthalpy of the air;

[0032] A hot water valve and a preheating coil, wherein the preheating coil is heated by the hot water valve to increase the enthalpy of the air;

[0033] And, the valve control system as described in the first aspect above.

[0034] It can be seen that the valve control method provided in the embodiment of the present application obtains the current enthalpy value of the air; based on the current enthalpy value and the set target enthalpy value, the PID algorithm is used to determine the current control variable currently used to control the valve opening; and then, based on the multiple sub-range intervals of the control variable, the current sub-range interval corresponding to the current control variable can be determined; wherein, the multiple sub-range intervals include a first sub-range interval, a second sub-range interval and a stop sub-range interval; and then, based on the control logic corresponding to each sub-range interval, the valve control information of the control valve corresponding to the current sub-range interval can be determined; wherein, the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop moving. That is to say, when the embodiment of the present application controls the valve opening based on the control variable, the control variable is divided into different sub-ranges, and then the control valve corresponding to the sub-range, such as the cold water valve or the hot water valve, can be controlled according to the control logic corresponding to the different sub-ranges. That is, the control method is sub-range control, which can achieve efficient and precise control of the cold water valve and the hot water valve; at the same time, the sub-range interval includes a stop sub-range interval corresponding to the control valve to stop the action, so that in special environments (such as transition seasons), the cold water valve and the hot water valve can be controlled to stop the action, thereby avoiding energy waste caused by cold and hot hedging. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0036] Figure 1 It is a flow chart of the valve control method provided in the embodiment of the present application;

[0037] Figure 2 It is a schematic diagram of the relationship between the control variable and the valve opening;

[0038] Figure 3 This is a schematic diagram of the structure of the valve control system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions 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 are within the scope of protection of this application.

[0040] Heating and ventilation (HVAC) is a comprehensive system covering heating, ventilation, and air conditioning, which is used to regulate the temperature, humidity, air quality, and ventilation of indoor environments (such as laboratories); and MAU (Make-up Air Unit) is a part of the HVAC system, belonging to the ventilation and air conditioning part, and is mainly responsible for the processing and delivery of fresh air. Its core functions include: introducing fresh air and sending outdoor fresh air into the room; filtering and purifying to remove dust, particulate matter and other pollutants in the air; temperature and humidity regulation: heating, cooling, humidifying or dehumidifying the fresh air to meet the requirements of the indoor environment; therefore, in clean rooms, semiconductor factories and other places with extremely high requirements for air quality, MAU is an indispensable key equipment in the HVAC system.

[0041] When the MAU system adjusts the temperature and humidity, it needs to heat, cool, and other processes on the air, so hot and cold valves are used to control the flow of hot and cold water to adjust the air temperature; for example, in winter, the hot water valve is opened to heat the fresh air, and in summer, the cold water valve is opened to cool the fresh air.

[0042] Specifically, during the isenthalpic humidification process of the MAU air-conditioning system, under different working conditions (winter conditions, summer conditions, transitional season conditions), the opening and closing states of the cold water valve and the hot water valve can be controlled, so that the MAU can process and produce air that meets the temperature and humidity requirements under different working conditions.

[0043] In thermodynamics, enthalpy is an important state parameter that characterizes the energy of a material system. It is equal to the sum of the internal energy and the product of pressure and volume, and is usually represented by the symbol H. In a chemical reaction, the change in enthalpy (△H) is equal to the heat absorbed or released by the system; "Isenthalpic humidification" is a common air treatment process in HVAC systems. This process occurs in the humidification section of central air conditioning units and is widely used in many fields; the isenthalpic humidification process is a cooling and humidification process. During the whole process, the moisture content of the air increases, and the relative humidity increases. However, when water changes from small droplets to water vapor, it absorbs heat in the air and the air temperature decreases; therefore, the enthalpy value of the air remains unchanged before and after humidification.

[0044] However, in transitional seasons (9°C < outdoor dew point temperature < 14°C) and other environments, the operating conditions of the MAU system are more complicated, and the control logic of the cold water valve and the hot water valve can easily cause the phenomenon of cold and hot hedging, resulting in energy waste.

[0045] In view of this, an embodiment of the present application provides a valve control method, which can achieve efficient and accurate control of cold water valves and hot water valves to avoid energy waste.

[0046] like Figure 1 As shown, Figure 1 is a flow chart of a valve control method provided in an embodiment of the present application, and the valve control method comprises the following steps.

[0047] Step S101: Obtain the current enthalpy value of air.

[0048] In an embodiment of the present application, the current enthalpy value of the air can be obtained through an enthalpy sensor; the enthalpy sensor is a device for measuring the enthalpy value of air, which is composed of a temperature sensor and a humidity sensor. The current enthalpy value of the air can be automatically calculated through the measured temperature and humidity data combined with the enthalpy calculation formula.

[0049] In an optional implementation, the current enthalpy value measured by the enthalpy sensor can be automatically output to the user operation interface, and the current enthalpy value can provide a basis for subsequent control of the opening of the cold water valve or the hot water valve.

[0050] Step S102: Based on the current enthalpy value and the set target enthalpy value, a current control variable currently used to control the valve opening is determined using a PID algorithm.

[0051] In the specific implementation, the user can input the set target enthalpy value in advance through the operation interface, that is, the target value expected to be achieved. The set target enthalpy value can ensure that the air supply state meets the process requirements or adapts to different working conditions and other requirements; for example, based on the current working conditions or process requirements, it is expected to control the enthalpy value at 27kj / kg (kilojoules / kilogram) by controlling the cold water valve and the hot water valve, then 27 is the set target enthalpy value.

[0052] However, the current enthalpy value of the air obtained may not match the set target enthalpy value, and there may be an error. Therefore, it is necessary to make timely adjustments to ensure that the actual current enthalpy value meets the set target enthalpy value requirements.

[0053] In the embodiment of the present application, the control variable can be adjusted in time through PID (Proportional-Integral-Derivative) operation, and the valve opening of the cold water valve or the hot water valve can be controlled through the control variable to adjust the temperature and humidity of the air, thereby achieving the adjustment of the current enthalpy value so that the adjusted current enthalpy value can meet the set target enthalpy value requirement.

[0054] In an optional implementation, the current control variable may be obtained by determining a control deviation formed by a current enthalpy value and a set target enthalpy value, performing PID operation and linear conversion on the control deviation.

[0055] The control deviation is the difference between the current enthalpy value and the set target enthalpy value. The process of performing PID operation on the control deviation may include: proportional control (P), adjusting the control variable proportionally according to the size of the control deviation. The larger the control deviation, the greater the adjustment force and the faster the response speed; integral control (I), performing integral operation on the control deviation to eliminate static errors. The larger the integral coefficient, the stronger the system's ability to eliminate static errors; differential control (D), performing differential operation on the rate of change of the control deviation, adjusting the control variable, and preventing the valve control system from oscillating.

[0056] Furthermore, in order to fully utilize the advantages of each control action, the PID operation result output by the PID operation of the control deviation can be linearly converted into the current control variable, thereby achieving fast, stable and precise control of the valve control system.

[0057] In an optional example, the following formula may be used:

[0058]

[0059] Perform PID operation on the control deviation to obtain the current control variable, where u(t) is the current control variable output by PID operation, K p is the proportional coefficient (i.e. proportional gain), K i is the integral coefficient (i.e. integral gain), K d is the differential coefficient (i.e., differential gain), e(t) is the error, i.e., the error between the current enthalpy value and the target enthalpy value, ∫e(t)d(t) is the integral of the error, is the differential of the error, and t is the time.

[0060] Step S103: Based on a plurality of split ranges of the control variable, determine a current split range corresponding to the current control variable; wherein the plurality of split ranges include a first split range, a second split range, and a stop split range.

[0061] In an embodiment of the present application, the control of the valve includes the control of the cold water valve and the hot water valve. When controlling the valve opening, different working conditions need to be considered. For example, in winter, the hot water valve needs to be opened for heating, while the cold water valve does not need to be opened; in summer, the cold water valve needs to be opened for cooling, while the hot water valve does not need to be opened to ensure that the air enthalpy value meets the set target enthalpy value requirements.

[0062] In order to adapt to different working conditions, the embodiment of the present application adopts a split-range control scheme to control the valve opening. Split-range control is a method of decomposing a complex task into multiple subtasks and controlling them separately, which can improve control efficiency and adapt to a variety of different working conditions.

[0063] After obtaining the current control variable after PID calculation and linear conversion, the current sub-range interval corresponding to the current control variable can be determined based on multiple sub-range intervals of the control variable, and then the valve opening can be controlled according to the control logic corresponding to different sub-range intervals.

[0064] In the embodiment of the present application, before determining the corresponding sub-range interval of the current control variable, it is necessary to first divide and determine a plurality of sub-range intervals of the control variable.

[0065] Figure 2 This is a schematic diagram of the relationship between the control variable and the valve opening. Figure 2 , the sub-range of this application and the corresponding relationship between the control variable and the valve opening are introduced in detail.

[0066] like Figure 2 As shown, in an embodiment of the present application, the multiple sub-range intervals may include a first sub-range interval, a second sub-range interval and a stop sub-range interval; wherein the first sub-range interval, the stop sub-range interval and the second sub-range interval are multiple sub-range intervals with continuous control variables; the control variable range of the first sub-range interval is smaller than the control variable range of the stop sub-range interval; the control variable range of the stop sub-range interval is smaller than the control variable range of the second sub-range interval.

[0067] Among them, the first sub-range interval, the stop sub-range interval and the second sub-range interval are multiple sub-range intervals with continuous control variables, that is, the stop sub-range interval is located between the first sub-range interval and the second sub-range interval, and connects the first sub-range interval and the second sub-range interval, and the stop sub-range interval serves as a transition between the two sub-range intervals.

[0068] The specific process of dividing the three sub-range intervals is introduced below. First, the set reference point and the set error value of the control variable are determined. Then, based on the reference point and the set error value, the first endpoint value and the second endpoint value corresponding to the stop sub-range interval can be determined; wherein, the first endpoint value is the value of the reference point minus the error value, and the second endpoint value is the value of the reference point plus the error value.

[0069] In the embodiment of the present application, the reference point and the set error value can be pre-set by the user and input through the operation interface.

[0070] In an optional embodiment, the reference point may be set to the midpoint value of the entire control variable range. For example, assuming that the entire control variable range is 0-100%, the reference point may be set to 50%.

[0071] In other embodiments, corresponding reference point values ​​may be set according to specific requirements.

[0072] The set error value is used to divide the stop range, such as Figure 2 As shown, a "dead zone" is set on the left and right of the reference point, and the size of the "dead zone" corresponds to the absolute value of the error value. Therefore, the two endpoint values ​​corresponding to the stop sub-range interval are the value of the reference point plus or minus the error value, respectively, wherein the first endpoint value is the value of the reference point minus the error value, and the second endpoint value is the value of the reference point plus the error value, that is, the stop sub-range interval is [first endpoint value, second endpoint value]; within the stop sub-range interval, the valves are controlled to stop moving, including the cold water valve and the hot water valve, to avoid the phenomenon of cold and hot hedge.

[0073] In an optional embodiment, assuming that the reference point is 50% and the set error value is 0.5, the first endpoint value is 49.5%, the second endpoint value is 50.5%, and the stop range interval is [49.5%, 50.5%]. If the current control variable is within the stop range interval, the control valve stops moving.

[0074] In other embodiments, corresponding error values ​​may be set according to specific requirements.

[0075] Further, a control variable range smaller than the stop split range is determined as a first split range; and a control variable range larger than the stop split range is determined as a second split range.

[0076] At this point, the first split range, the stop split range and the second split range are divided.

[0077] Furthermore, based on the multiple sub-range intervals of the control variable, the current sub-range interval corresponding to the current control variable can be determined.

[0078] Step S104: Based on the control logic corresponding to each sub-range interval, determine the valve control information of the control valve corresponding to the current sub-range interval; wherein, the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop action.

[0079] In the embodiment of the present application, based on the control logic corresponding to each sub-range interval, valve control information of the control valve corresponding to the current sub-range interval can be determined, and the valve control information is used to control the opening of each valve.

[0080] Among them, combined Figure 2 In an optional example, the control logic of the first sub-range interval may be: based on the inverse relationship between the control variable and the valve opening of the cold water valve, controlling the valve opening of the cold water valve; wherein, when the control variable is equal to the first endpoint value, the valve opening of the cold water valve corresponds to the lower limit value of the opening.

[0081] The lower limit value of the valve opening, that is, the minimum value of the valve opening, can be input in advance by the user through the user operation interface. In the embodiment of the present application, the lower limit value of the opening can be set to 0.

[0082] The upper limit value of the valve opening, that is, the maximum value of the valve opening, can be input in advance by the user through the user operation interface. In the embodiment of the present application, the upper limit value of the valve opening can be set to 100%.

[0083] from Figure 2 It can be seen that the valve opening of the cold water valve is inversely proportional to the size of the control variable, that is, the valve opening of the cold water valve gradually decreases with the increase of the control variable. When the control variable is 0, the valve opening of the cold water valve is the largest. When the control variable is the first endpoint value, the valve opening of the cold water valve reaches the minimum, that is, the lower limit of the opening, and begins to transition to opening the hot water valve.

[0084] In an optional implementation, if the current sub-range interval is the first sub-range interval, based on the inverse proportional relationship between the control variable and the valve opening of the cold water valve, the control opening of the cold water valve corresponding to the current control variable can be determined; then, based on the control opening of the cold water valve, the valve control information for controlling the cold water valve is determined, and according to the valve control information, the valve opening of the cold water valve is controlled.

[0085] Furthermore, when the current control variable is in the stop range, both the cold water valve and the hot water valve are controlled to stop operating to adapt to special working conditions, such as in transitional seasons, to avoid cold and hot hedging and energy waste.

[0086] Continue to combine Figure 2 In another optional example, the control logic of the second sub-range interval may be: based on the proportional relationship between the control variable and the valve opening of the hot water valve, controlling the valve opening of the hot water valve; wherein, when the control variable is equal to the second endpoint value, the valve opening of the hot water valve corresponds to the lower limit value of the opening.

[0087] from Figure 2 It can be seen that the valve opening of the hot water valve is directly proportional to the size of the control variable, that is, the valve opening of the hot water valve gradually increases with the increase of the control variable. When the control variable is the second endpoint value, the valve opening of the hot water valve is the smallest. When the control variable reaches the maximum value, the valve opening of the hot water valve reaches the maximum, that is, the upper limit value of the opening.

[0088] In an optional implementation, if the current sub-range interval is the second sub-range interval, based on the proportional relationship between the control variable and the valve opening of the hot water valve, the control opening of the hot water valve corresponding to the current control variable can be determined; then, based on the control opening of the hot water valve, the valve control information for controlling the hot water valve is determined, and according to the valve control information, the valve opening of the hot water valve is controlled.

[0089] It should be noted that in the embodiment of the present application, the lower limit value of the valve opening of the cold water valve is the same as the lower limit value of the valve opening of the hot water valve, and the upper limit value of the valve opening of the cold water valve is also the same as the upper limit value of the valve opening of the hot water valve.

[0090] It can be seen that the valve control method provided in the embodiment of the present application obtains the current enthalpy value of the air; based on the current enthalpy value and the set target enthalpy value, the PID algorithm is used to determine the current control variable currently used to control the valve opening; and then, based on the multiple sub-range intervals of the control variable, the current sub-range interval corresponding to the current control variable can be determined; wherein, the multiple sub-range intervals include a first sub-range interval, a second sub-range interval and a stop sub-range interval; and then, based on the control logic corresponding to each sub-range interval, the valve control information of the control valve corresponding to the current sub-range interval can be determined; wherein, the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop moving. That is to say, when the embodiment of the present application controls the valve opening based on the control variable, the control variable is divided into different sub-ranges, and then the control valve corresponding to the sub-range, such as the cold water valve or the hot water valve, can be controlled according to the control logic corresponding to the different sub-ranges. That is, the control method is sub-range control, which can achieve efficient and precise control of the cold water valve and the hot water valve; at the same time, the sub-range interval includes a stop sub-range interval corresponding to the control valve to stop the action, so that in special environments (such as transition seasons), the cold water valve and the hot water valve can be controlled to stop the action, thereby avoiding energy waste caused by cold and hot hedging.

[0091] Correspondingly, an embodiment of the present application also provides a valve control system. The valve control system described below can refer to the solution content described above, wherein the core control function of the valve control system can be implemented by a PLC (Programmable Logic Controller).

[0092] Figure 3 The schematic diagram of the structure of the valve control system provided in the embodiment of the present application is as follows: Figure 3 As shown, the valve control system may include:

[0093] The current control variable determination module 310 is used to determine the current control variable currently used to control the valve opening by using a PID algorithm based on the current enthalpy value of the air and the set target enthalpy value;

[0094] The sub-range control module 320 is used to determine the current sub-range interval corresponding to the current control variable based on multiple sub-range intervals of the control variable; wherein the multiple sub-range intervals include a first sub-range interval, a second sub-range interval and a stop sub-range interval; based on the control logic corresponding to each sub-range interval, the valve control information of the control valve corresponding to the current sub-range interval is determined; wherein the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop operating.

[0095] In an optional implementation, the first sub-range interval, the stop sub-range interval and the second sub-range interval are multiple sub-range intervals with continuous control variables; the control variable range of the first sub-range interval is smaller than the control variable range of the stop sub-range interval; the control variable range of the stop sub-range interval is smaller than the control variable range of the second sub-range interval.

[0096] In an optional implementation, the valve control system is also used to:

[0097] Determine a set reference point and a set error value of the control variable, and determine a first endpoint value and a second endpoint value corresponding to the stop split range; wherein the first endpoint value is the value of the reference point minus the error value, and the second endpoint value is the value of the reference point plus the error value;

[0098] The control variable range smaller than the stop split range is determined as the first split range; the control variable range larger than the stop split range is determined as the second split range.

[0099] In an optional implementation, the control logic of the first sub-range interval is specifically: based on the inverse relationship between the control variable and the valve opening of the cold water valve, the valve opening of the cold water valve is controlled; wherein, when the control variable is equal to the first endpoint value, the valve opening of the cold water valve corresponds to the lower limit value of the opening;

[0100] The control logic of the second sub-range interval is specifically: based on the proportional relationship between the control variable and the valve opening of the hot water valve, the valve opening of the hot water valve is controlled; wherein, when the control variable is equal to the second endpoint value, the valve opening of the hot water valve corresponds to the lower limit value of the opening.

[0101] In an optional implementation, the sub-range control module 320 is used to determine the valve control information of the control valve corresponding to the current sub-range interval based on the control logic corresponding to each sub-range interval, including:

[0102] If the current sub-range interval is the first sub-range interval, based on the inverse relationship between the control variable and the valve opening of the cold water valve, determining the control opening of the cold water valve corresponding to the current control variable;

[0103] Based on the controlled opening of the cold water valve, valve control information for controlling the cold water valve is determined.

[0104] In an optional implementation, the sub-range control module 320 is used to determine the valve control information of the control valve corresponding to the current sub-range interval based on the control logic corresponding to each sub-range interval, including:

[0105] If the current sub-range interval is the second sub-range interval, based on the proportional relationship between the control variable and the valve opening of the hot water valve, determining the control opening of the hot water valve corresponding to the current control variable;

[0106] Based on the control opening of the hot water valve, valve control information for controlling the hot water valve is determined.

[0107] In an optional implementation, the current control variable determination module 310 is used to determine the current control variable currently used to control the valve opening based on the current enthalpy value and the set target enthalpy value using the PID algorithm, including:

[0108] A control deviation between a current enthalpy value and a set target enthalpy value is determined, and a PID operation and a linear conversion are performed on the control deviation to obtain a current control variable.

[0109] In an optional implementation, the current control variable determination module 310 includes:

[0110] The PID module 311 is used to perform PID operation on the control deviation constituted by the current enthalpy value and the set target enthalpy value, and output the PID operation result;

[0111] The linear conversion module 312 is used to perform linear conversion on the PID operation result to obtain the current control variable.

[0112] In a further optional implementation, the embodiment of the present application also provides a MAU system, including: an enthalpy sensor for detecting the current enthalpy value of the air; a cold water valve and a precooling coil, wherein the precooling coil is cooled by the cold water valve to reduce the enthalpy value of the air; a hot water valve and a preheating coil, wherein the preheating coil is heated by the hot water valve to increase the enthalpy value of the air; and a valve control system as described in the aforementioned embodiment.

[0113] The above describes multiple implementation schemes provided by the embodiments of the present application. The various optional methods introduced in each implementation scheme can be combined and cross-referenced with each other without conflict, thereby extending a variety of possible implementation schemes, which can all be considered as implementation schemes disclosed and open in the embodiments of the present application.

[0114] Although the embodiments of the present application are disclosed above, the present application is not limited thereto. Any person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be subject to the scope defined by the claims.

Claims

1. A valve control method, characterized in that: include: Get the current enthalpy value of air; Based on the current enthalpy value and the set target enthalpy value, the current control variable currently used to control the valve opening is determined using the PID algorithm; Based on a plurality of split ranges of the control variable, determining a current split range corresponding to the current control variable; wherein the plurality of split ranges include a first split range, a second split range, and a stop split range; Based on the control logic corresponding to each sub-range interval, the valve control information of the control valve corresponding to the current sub-range interval is determined; wherein, the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop action.

2. The valve control method according to claim 1, characterized in that: The first sub-range interval, the stop sub-range interval and the second sub-range interval are multiple sub-range intervals with continuous control variables; the control variable range of the first sub-range interval is smaller than the control variable range of the stop sub-range interval; the control variable range of the stop sub-range interval is smaller than the control variable range of the second sub-range interval.

3. The valve control method according to claim 2, characterized in that: Also includes: Determine a set reference point and a set error value of the control variable, and determine a first endpoint value and a second endpoint value corresponding to the stop split range; wherein the first endpoint value is the value of the reference point minus the error value, and the second endpoint value is the value of the reference point plus the error value; The control variable range smaller than the stop split range is determined as the first split range; the control variable range larger than the stop split range is determined as the second split range.

4. The valve control method according to claim 3, characterized in that: The control logic of the first sub-range interval is specifically: based on the inverse relationship between the control variable and the valve opening of the cold water valve, the valve opening of the cold water valve is controlled; wherein, when the control variable is equal to the first endpoint value, the valve opening of the cold water valve corresponds to the lower limit value of the opening; The control logic of the second sub-range interval is specifically: based on the proportional relationship between the control variable and the valve opening of the hot water valve, the valve opening of the hot water valve is controlled; wherein, when the control variable is equal to the second endpoint value, the valve opening of the hot water valve corresponds to the lower limit value of the opening.

5. The valve control method according to claim 4, characterized in that: The determining of the valve control information of the control valve corresponding to the current sub-range interval based on the control logic corresponding to each sub-range interval includes: If the current sub-range interval is the first sub-range interval, based on the inverse relationship between the control variable and the valve opening of the cold water valve, determining the control opening of the cold water valve corresponding to the current control variable; Based on the controlled opening of the cold water valve, valve control information for controlling the cold water valve is determined.

6. The valve control method according to claim 4, characterized in that: The determining of the valve control information of the control valve corresponding to the current sub-range interval based on the control logic corresponding to each sub-range interval includes: If the current sub-range interval is the second sub-range interval, based on the proportional relationship between the control variable and the valve opening of the hot water valve, determining the control opening of the hot water valve corresponding to the current control variable; Based on the control opening of the hot water valve, valve control information for controlling the hot water valve is determined.

7. The valve control method according to claim 1, characterized in that: The method of determining the current control variable for controlling the valve opening based on the current enthalpy value and the set target enthalpy value by using the PID algorithm includes: A control deviation between a current enthalpy value and a set target enthalpy value is determined, and a PID operation and a linear conversion are performed on the control deviation to obtain a current control variable.

8. A valve control system, characterized in that: include: A current control variable determination module is used to determine the current control variable currently used to control the valve opening by using a PID algorithm based on the current enthalpy value of the air and the set target enthalpy value; The sub-range control module is used to determine the current sub-range interval corresponding to the current control variable based on multiple sub-range intervals of the control variable; wherein the multiple sub-range intervals include a first sub-range interval, a second sub-range interval and a stop sub-range interval; based on the control logic corresponding to each sub-range interval, the valve control information of the control valve corresponding to the current sub-range interval is determined; wherein the control logic of the first sub-range interval corresponds to controlling the opening of the cold water valve, the control logic of the second sub-range interval corresponds to controlling the opening of the hot water valve, and the control logic of the stop sub-range interval corresponds to controlling the valve to stop operating.

9. The valve control system according to claim 8, characterized in that: The current control variable determination module includes: A PID module, for performing PID operation on a control deviation constituted by a current enthalpy value and a set target enthalpy value, and outputting a PID operation result; The linear conversion module is used to perform linear conversion on the PID operation result to obtain the current control variable.

10. A MAU system, characterized in that: include: Enthalpy sensor, used to detect the current enthalpy value of air; A cold water valve and a pre-cooling coil, wherein the pre-cooling coil is cooled by the cold water valve to reduce the enthalpy of the air; A hot water valve and a preheating coil, wherein the preheating coil is heated by the hot water valve to increase the enthalpy of the air; And, a valve control system as described in any one of claims 8-9.

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