A method for determining true value of refrigeration room sensors based on multi-dimensional constraints

Abstract

The present invention provides a method for determining the true value of a sensor in a refrigeration room based on multidimensional constraints, comprising the following steps: step 10, establishing a multidimensional sensor true value logical association constraint relationship according to the sensor layout structure in the refrigeration room; step 20, constructing an inconsistency function group according to the multidimensional sensor true value logical association constraint relationship; step 30, collecting the measurement data of the sensor in the refrigeration room within a preset time period, and constructing a steady-state measurement data set; step 40, using the inconsistency function group to calculate the associated inconsistency value of the measurement data in the steady-state measurement data set, if all the associated inconsistency values ​​of the measurement data are less than the inconsistency threshold, the measurement data is considered to be a true value. The method for determining the true value of a sensor in a refrigeration room based on multidimensional constraints provided by the present invention can determine whether the measurement value of the sensor is a true value, thereby performing data screening and calibrating the sensor.

Description

Technical Field

[0001] The invention belongs to the technical field of sensor calibration, and in particular relates to a method for determining the true value of a refrigeration room sensor based on multi-dimensional constraints. Background Art

[0002] An efficient refrigeration room requires continuous monitoring of various physical measurement data (such as temperature, pressure, flow, etc.), electrical signal data (such as current, power, etc.) and operating status data (such as control signals, valve opening, etc.). After a long period of operation, various sensors working under complex working conditions (such as high temperature, humidity, corrosion, etc.) are easily affected by factors such as equipment aging or noise interference, and are prone to typical failures such as complete failure, fixed deviation, drift deviation and reduced accuracy, which seriously affect the data quality of the monitoring system. For example, the temperature and flow sensors on the refrigeration system side are particularly important parameters in the operation of the refrigeration room. The accuracy of the sensor measurement directly affects the equipment fault diagnosis and operation control of the refrigeration room. Finding the true value of the measurement object is a technical problem in the field of sensor calibration, which is usually provided directly by standard sensors or indirectly estimated by mathematical models. However, these methods are either costly or have questionable accuracy, and are difficult to apply to multi-sensor monitoring under variable working conditions. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a refrigeration room sensor true value judgment method based on multi-dimensional constraints, which can judge whether the measured value of the sensor is a true value, thereby performing data screening and calibrating the sensor.

[0004] To solve the above technical problems, the embodiments of the present invention adopt the following technical solutions:

[0005] The embodiment of the present invention provides a method for determining the true value of a refrigeration room sensor based on multi-dimensional constraints, comprising the following steps:

[0006] Step 10, establishing a multi-dimensional sensor truth value logical association constraint relationship according to the sensor layout structure in the refrigeration room;

[0007] Step 20, constructing an inconsistency function group according to the multi-dimensional sensor truth value logical association constraint relationship;

[0008] Step 30, collecting measurement data of sensors in the refrigeration room within a preset time period to construct a steady-state measurement data set;

[0009] Step 40: Calculate the associated inconsistency values ​​of the measurement data in the steady-state measurement data set using the inconsistency function group. If all associated inconsistency values ​​of the measurement data are less than an inconsistency threshold, the measurement data is considered to be a true value.

[0010] As a further improvement of the embodiment of the present invention, the multi-dimensional sensor truth value logical association constraint relationship includes temperature consistency association constraint, mass conservation association constraint and energy conservation association constraint.

[0011] As a further improvement of the embodiment of the present invention, in step 10, if the sensor arrangement structure in the refrigeration room is: a temperature sensor and a flow sensor are provided on the chilled water return main pipe and the chilled water return branch pipe, a temperature sensor is provided on the chilled water supply branch pipe and the chilled water supply main pipe; a flow sensor is provided on the chilled water bypass pipe between the chilled water supply main pipe and the chilled water return main pipe;

[0012] Establish the consistency constraint relationship of chilled water return temperature shown in formula (1):

[0013] T chw,r1 =…=T chw,ri =…=T chw ,rn Formula (1)

[0014] Where, T chw,ri represents the chilled water return temperature of the i-th chiller, and n represents the number of chillers;

[0015] Establish the chilled water quality conservation constraint relationship shown in formula (2):

[0016]

[0017] Where M chw,0 Indicates the chilled water flow rate of the chilled water main, M chw,i represents the chilled water flow rate of the chilled water branch pipe where the i-th chiller is located, M chw,p Indicates the chilled water flow rate of the chilled water bypass pipe;

[0018] Establish the associated constraint relationship of chilled water energy conservation shown in formula (3):

[0019]

[0020] Where, T chw,s0 Indicates the chilled water temperature of the chilled water supply main, T chw,r0 Indicates the chilled water temperature of the chilled water return main, T chw,si represents the chilled water supply temperature of the i-th chiller, Represents the average value of the chilled water supply temperature of all chillers, Indicates the average value of the chilled water return temperature of all chillers;

[0021] The consistency association constraint relationship of chilled water return temperature, the conservation association constraint relationship of chilled water quality and the conservation association constraint relationship of chilled water energy constitute the truth value logic association constraint relationship of multi-dimensional sensors.

[0022] As a further improvement of the embodiment of the present invention, in step 10, according to the chilled water return temperature consistency association constraint relationship, a chilled water return temperature inconsistency function shown in formula (4) is constructed:

[0023]

[0024] In the formula, Indicates the inconsistency value of the chilled water return temperature. It represents the average value of chilled water return temperature of all chillers.

[0025] As a further improvement of the embodiment of the present invention, in step 10, according to the associated constraint relationship of the chilled water quality conservation, the inconsistency function of the chilled water quality conservation shown in formula (5) is constructed:

[0026]

[0027] In the formula, Indicates the inconsistency value of chilled water quality conservation.

[0028] As a further improvement of the embodiment of the present invention, in step 20, according to the associated constraint relationship of the chilled water energy conservation, the chilled water energy conservation inconsistency function shown in formula (6) is constructed:

[0029]

[0030] Where U chw Indicates the inconsistency value of chilled water energy conservation.

[0031] As a further improvement of the embodiment of the present invention, in step 10, if the sensor arrangement structure in the refrigeration room is: a temperature sensor and a flow sensor are provided on the cooling water return main pipe and the cooling water return branch pipe, a temperature sensor is provided on the cooling water supply branch pipe and the cooling water return main pipe; a flow sensor is provided on the cooling water bypass pipe between the cooling water supply main pipe and the cooling water return main pipe;

[0032] Establish the cooling water return temperature consistency constraint relationship shown in formula (7):

[0033] T cw,r0 =T cw,r1 =…=T cw,ri =…=T cw ,rn Formula (7)

[0034] Where, T cw,r0 Indicates the cooling water temperature of the cooling water return main, T cw,ri represents the cooling water return temperature of the i-th chiller;

[0035] Establish the cooling water quality conservation constraint relationship shown in formula (8):

[0036]

[0037] Where M cw,0 Indicates the cooling water flow rate of the cooling water main, M cw,i represents the cooling water flow rate of the cooling water branch pipe where the i-th chiller is located, M cw,p Indicates the cooling water flow rate of the cooling water bypass pipe;

[0038] Establish the cooling water energy conservation constraint relationship shown in formula (9):

[0039]

[0040] Where, T cw,s0 Indicates the cooling water temperature of the cooling water supply main, T cw,r0 Indicates the cooling water temperature of the cooling water return main, T cw,si represents the cooling water supply temperature of the i-th chiller, Represents the average cooling water supply temperature of all chillers, Indicates the average cooling water return temperature of all chillers;

[0041] The cooling water return temperature consistency associated constraint relationship, cooling water quality conservation associated constraint relationship and cooling water energy conservation associated constraint relationship constitute the multi-dimensional sensor truth value logic associated constraint relationship.

[0042] As a further improvement of the embodiment of the present invention, in step 20, according to the cooling water return temperature consistency association constraint relationship, the cooling water return temperature inconsistency function shown in formula (10) is constructed:

[0043]

[0044] In the formula, Indicates the cooling water return temperature inconsistency value. Indicates the average value of the chilled water return temperature of all chillers;

[0045] According to the associated constraint relationship of cooling water quality conservation, the inconsistency function of cooling water quality conservation shown in formula (11) is constructed:

[0046]

[0047] In the formula, Indicates the inconsistency value of cooling water quality conservation;

[0048] According to the associated constraint relationship of cooling water energy conservation, the cooling water energy conservation inconsistency function shown in formula (12) is constructed:

[0049]

[0050] Where U cw Indicates the inconsistency value of cooling water energy conservation.

[0051] As a further improvement of the embodiment of the present invention, the step 30 specifically includes:

[0052] Step 301, collecting measurement data of sensors in the refrigeration room within a preset time period, and using a rolling time window to pre-process the measurement data of each sensor in different time periods;

[0053] Step 302, using formula (13) to calculate the coefficient of variation of the data of each sensor in each time period:

[0054]

[0055] In the formula, CV represents the coefficient of variation of the data, σ represents the standard deviation of the data, and μ represents the mean value;

[0056] Step 303 : Select the measurement data of the time period in which the data variation coefficients of all sensors are less than the coefficient threshold to form the steady-state measurement data.

[0057] As a further improvement of the embodiment of the present invention, the inconsistency threshold is 5%.

[0058] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0059] An embodiment of the present invention provides a method for determining the true value of a refrigeration room sensor based on multidimensional constraints. First, according to the sensor layout structure in the refrigeration room, a multidimensional sensor true value logical association constraint relationship is established. The established multidimensional sensor true value logical association constraint relationship is inherent to the system and conforms to the laws of physical logic. Then, according to the multidimensional sensor true value logical association constraint relationship, an inconsistency function group is constructed. Then, sensor measurement data is collected to construct a steady-state measurement data set. Finally, the inconsistency function group is used to calculate the inconsistency value of the measurement data, that is, to determine whether the measurement data satisfies the true value logical association constraint relationship. If so, the measurement data is considered to be true. If not, the measurement data needs to be discarded or the sensor needs to be calibrated, so as to avoid the influence of sensor failure on the fault diagnosis and operation optimization strategy of thermal equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0061] Figure 1 is a flow chart of a method according to an embodiment of the present invention;

[0062] Figure 2 The diagram is a schematic diagram of a sensor layout structure of a refrigeration room in an embodiment of the present invention. DETAILED DESCRIPTION

[0063] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings.

[0064] The embodiment of the present invention provides a method for determining the true value of a refrigeration room sensor based on multi-dimensional constraints, such as Figure 1 As shown, the following steps are included:

[0065] Step 10: Establish a multi-dimensional sensor truth value logic association constraint relationship based on the sensor layout structure in the refrigeration room. Construct an inconsistency function group based on the multi-dimensional sensor truth value logic association constraint relationship.

[0066] Step 20: Collect measurement data from sensors in the refrigeration room within a preset time period to construct a steady-state measurement data set.

[0067] Step 30, using the inconsistency function group to calculate the associated inconsistency value of each measurement data in the steady-state measurement data set, if all associated inconsistency values ​​of the measurement data are less than the inconsistency threshold, the measurement data is considered to be a true value.

[0068] The method of the embodiment of the present invention first establishes a multi-dimensional sensor truth value logical association constraint relationship according to the sensor layout structure in the refrigeration room. The multi-dimensional sensor truth value logical association constraint relationship is inherent in the system and conforms to the physical logic law; then, according to the multi-dimensional sensor truth value logical association constraint relationship, an inconsistency function group is constructed; then, the sensor measurement data is collected to construct a steady-state measurement data set; finally, the inconsistency value of the measurement data is calculated using the inconsistency function group, that is, whether the measurement data satisfies the truth value logical association constraint relationship. If so, the measurement data is considered to be true; if not, the measurement data needs to be discarded or the sensor needs to be calibrated, so as to avoid the sensor failure from affecting the fault diagnosis and operation optimization strategy of the thermal equipment.

[0069] Among them, multiple temperature sensors and flow sensors are arranged in the refrigeration room to monitor the temperature and flow of chilled water and cooling water. Preferably, the multi-dimensional sensor truth value logical association constraint relationship between temperature and flow includes temperature consistency association constraint, mass conservation association constraint and energy conservation association constraint.

[0070] The sensor layout structure in the refrigeration room is as follows: In the chilled water system, Figure 1 As shown, the chilled water main includes a chilled water return main and a chilled water supply main. A number of chilled water branches that are the same as the number of chillers are arranged between the chilled water return main and the chilled water supply main. The evaporator of the chiller is arranged on the chilled water branch. The section of the chilled water branch connected to the chilled water return main is the chilled water return branch, and the section connected to the chilled water supply main is the chilled water supply branch. Temperature sensors and flow sensors are arranged on the chilled water return main and the chilled water return branch, and temperature sensors and flow sensors are arranged on the chilled water supply branch and the chilled water supply main. A chilled water bypass pipe is arranged between the chilled water supply main and the chilled water return main, and the flow direction is from the chilled water supply main to the chilled water return main. A flow sensor is arranged on the chilled water bypass pipe.

[0071] In step 10, in the chilled water system, since the chilled water of the chilled water branch pipes where each chiller is located comes from the same fully mixed chilled water return main pipe, theoretically, when the sensor has no error, the chilled water return temperature values ​​of all chillers turned on at the same time should be equal. Establish the chilled water return temperature consistency association constraint relationship shown in formula (1):

[0072] T chw,r1 =…=T chw,ri =…=T chw,rn Formula (1)

[0073] Where, T chw,ri represents the chilled water return temperature of the i-th chiller, and n represents the number of chillers.

[0074] In the absence of leakage, the sum of the chilled water flow through each chilled water branch pipe plus the chilled water flow through the chilled water bypass pipe must match the flow in the chilled water main pipe, that is, the sum of the flow of all chilled water branches and the flow of the chilled water bypass pipe must be equal to the flow of the chilled water main pipe. Establish the chilled water mass conservation association constraint relationship shown in formula (2):

[0075]

[0076] Where M chw,0 Indicates the chilled water flow rate of the chilled water main, M chw,i represents the chilled water flow rate of the chilled water branch pipe where the i-th chiller is located, M chw,pIndicates the chilled water flow rate of the chilled water bypass pipe.

[0077] The chilled water from each chiller is mixed into the chilled water main and should satisfy the energy balance law:

[0078]

[0079] In the formula, Q chw,0 represents the cooling load of the chilled water main, Q chw,i represents the cooling load of the i-th chilled water branch, Q p Indicates the cooling load of the chilled water bypass pipe.

[0080] Further, according to the heat calculation formula, the chilled water energy conservation constraint relationship shown in formula (3) is established:

[0081]

[0082] Where, T chw,s0 Indicates the chilled water temperature of the chilled water supply main, T chw,r0 Indicates the chilled water temperature of the chilled water return main, T chw,si represents the chilled water supply temperature of the i-th chiller, Represents the average value of the chilled water supply temperature of all chillers, It represents the average value of chilled water return temperature of all chillers.

[0083] The consistency association constraint relationship of chilled water return temperature, the conservation association constraint relationship of chilled water quality and the conservation association constraint relationship of chilled water energy constitute the truth value logic association constraint relationship of multi-dimensional sensors.

[0084] In the above step 20, according to the consistency association constraint relationship of the chilled water return temperature, in order to characterize the deviation of the chilled water return temperature of multiple chillers, the temperature is normalized to the average absolute deviation of the chilled water return temperature of all chillers, and the chilled water return temperature inconsistency function shown in formula (4) is obtained:

[0085]

[0086] In the formula, Indicates the inconsistency value of the chilled water return temperature. It represents the average value of chilled water return temperature of all chillers.

[0087] According to the associated constraint relationship of chilled water quality conservation, in order to characterize the deviation between the chilled water flow rate of the chilled water main pipe and the sum of the chilled water flow rate of all chilled water branches and the chilled water flow rate of the chilled water bypass pipe, the inconsistency function of chilled water quality conservation shown in formula (5) is obtained by normalization processing:

[0088]

[0089] In the formula, Indicates the inconsistency value of chilled water quality conservation.

[0090] According to the associated constraint relationship of chilled water energy conservation, in order to characterize the deviation on both sides of equation (3), the chilled water energy conservation inconsistency function shown in equation (6) is obtained by normalization:

[0091]

[0092] Where U chw Indicates the inconsistency value of chilled water energy conservation.

[0093] The sensor layout structure in the refrigeration room is as follows: in the cooling water system, the cooling water main includes a cooling water return main and a cooling water supply main. A cooling water branch pipe that is the same number as the chillers is arranged between the cooling water return main and the cooling water supply main. The condenser of the chiller is arranged on the cooling water branch pipe. The section of the cooling water branch pipe connected to the cooling water return main is the cooling water return branch pipe, and the section connected to the cooling water supply main is the cooling water supply branch pipe. Temperature sensors and flow sensors are arranged on the cooling water return main and the cooling water return branch pipe, and temperature sensors and flow sensors are arranged on the cooling water supply branch pipe and the cooling water supply main. A cooling water bypass pipe is arranged between the cooling water supply main and the cooling water return main, and the flow direction is from the cooling water return main to the cooling water supply main. A flow sensor is arranged on the cooling water bypass pipe.

[0094] In step 10, in the cooling water system, since the cooling water of the cooling water branch pipes where each chiller is located comes from the same fully mixed cooling water return main pipe, theoretically, when the sensor has no error, the cooling water return temperature values ​​of all chillers turned on at the same time should be equal, and also equal to the cooling water return temperature of the cooling water return main pipe. Establish the cooling water return temperature consistency association constraint relationship shown in formula (7):

[0095] T cw,r0 =T cw,r1 =…=T cw,ri =…=T cw,rn Formula (7)

[0096] Where, T cw,r0 Indicates the cooling water temperature of the cooling water return main, T cw,ri Represents the cooling water return temperature of the i-th chiller.

[0097] In the absence of leakage, the sum of the cooling water flow through each cooling water branch pipe plus the cooling water flow of the cooling water bypass pipe must match the flow in the cooling water main pipe, that is, the sum of the flow of all cooling water branches and the flow of the cooling water bypass pipe must be equal to the flow of the cooling water main pipe. Establish the cooling water mass conservation association constraint relationship shown in formula (8):

[0098]

[0099] Where M cw,0 Indicates the cooling water flow rate of the cooling water main, M cw,i represents the cooling water flow rate of the cooling water branch pipe where the i-th chiller is located, M cw,p Indicates the cooling water flow rate of the cooling water bypass pipe.

[0100] The cooling water from each chiller is mixed into the cooling water main and should satisfy the energy balance law:

[0101]

[0102] In the formula, Q cw,0 represents the cooling load of the cooling water main, Q cw,i represents the cooling load of the cooling water branch where the i-th chiller is located, Q cw,p Indicates the cooling load of the cooling water bypass pipe.

[0103] Since the chilled water return temperature of the chiller is consistent and the flow rate satisfies the mass conservation, the cooling water energy conservation constraint relationship shown in formula (9) is established:

[0104]

[0105] Where, T cw,s0 Indicates the cooling water temperature of the cooling water supply main, T cw,r0 Indicates the cooling water temperature of the cooling water return main, T cw,si represents the cooling water supply temperature of the i-th chiller, Represents the average cooling water supply temperature of all chillers, It represents the average value of cooling water return temperature of all chillers.

[0106] The cooling water return temperature consistency associated constraint relationship, cooling water quality conservation associated constraint relationship and cooling water energy conservation associated constraint relationship constitute the multi-dimensional sensor truth value logic associated constraint relationship.

[0107] In step 20, according to the cooling water return temperature consistency association constraint relationship, the cooling water return temperature inconsistency function shown in formula (10) is constructed:

[0108]

[0109] In the formula, Indicates the cooling water return temperature inconsistency value. It represents the average value of chilled water return temperature of all chillers.

[0110] According to the associated constraint relationship of cooling water quality conservation, the inconsistency function of cooling water quality conservation shown in formula (11) is constructed:

[0111]

[0112] In the formula, Indicates the inconsistency value of cooling water quality conservation.

[0113] According to the associated constraint relationship of cooling water energy conservation, the cooling water energy conservation inconsistency function shown in formula (12) is constructed:

[0114]

[0115] Where U cw Indicates the inconsistency value of cooling water energy conservation.

[0116] Preferably, step 30 specifically includes:

[0117] Step 301, collect the measurement data of the sensors in the refrigeration room within a preset time period, and use a rolling time window to pre-process the measurement data of each sensor in different time periods. Preferably, the time period of the rolling time window is 30 minutes.

[0118] Step 302, using formula (13) to calculate the coefficient of variation of the data of each sensor in each time period:

[0119]

[0120] In the formula, CV represents the coefficient of variation of the data, σ represents the standard deviation of the data, and μ represents the mean value.

[0121] Step 303, select the measurement data of the time period in which the data variation coefficient of all sensors is less than the coefficient threshold to form a steady-state measurement data set. That is, only when the data variation coefficient of all sensors' measurement values ​​in the same time period is less than the coefficient threshold, the measurement values ​​of all sensors in the time period are added to the steady-state measurement data set. The coefficient threshold is set based on system experience and expected stability. Preferably, the coefficient threshold is 0.1.

[0122] The above embodiment uses the coefficient of variation as an indicator to measure the volatility of the measurement data, and the measurement data with a coefficient of variation less than the coefficient threshold constitute a steady-state measurement data set. The measurement data in the steady-state measurement data set has a small fluctuation, indicating that the system has reached a state of equilibrium and remains unchanged without external disturbances such as load changes, ambient temperature changes, etc., that is, a steady-state condition. The measurement parameters of the system in a steady-state condition satisfy the laws of physics. The steady-state measurement data set reflects the true performance of the system in an undisturbed state, and its data is more representative, which improves the accuracy of true value judgment.

[0123] In step 40, it is determined whether each measurement data in the steady-state measurement data set is a true value. Specifically, the measurement data is brought into its associated inconsistency function to calculate the inconsistency value. If all associated inconsistency values ​​of the measurement data are less than the inconsistency threshold, the measurement data is considered to be a true value. Preferably, the inconsistency threshold is 5%.

[0124] For example, the measured value of the temperature sensor on the chilled water return branch is substituted into formula (4) to calculate the inconsistency value of the chilled water return temperature, and the measured value of the temperature sensor on the chilled water return branch, the measured value of the flow sensor on the chilled water return branch, the measured value of the temperature sensor on the chilled water supply main pipe, and the measured value of the flow sensor on the chilled water return main pipe are substituted into formula (6) to calculate the inconsistency value of the conservation of energy of chilled water. If the inconsistency value of the chilled water return temperature and the inconsistency value of the conservation of energy of chilled water are both less than the inconsistency threshold, the measured value of the temperature sensor on the chilled water return branch is a true value, otherwise it is not a true value.

[0125] The method of the embodiment of the present invention constructs an inconsistency function group to measure the degree of consistency of the measured value with the multi-dimensional sensor true value logical association constraint relationship. If the inconsistency value is less than the inconsistency threshold, it means that the measured value at this time satisfies the multi-dimensional sensor true value logical association constraint relationship, and the measured value is close to the true value to the greatest extent.

[0126] The method of the embodiment of the present invention can be used for true value judgment of the measurement values ​​of the freezing side temperature sensor and flow sensor of the refrigeration room, or for true value judgment of the measurement values ​​of the cooling side temperature sensor and flow sensor of the refrigeration room, or for true value judgment of the measurement values ​​of the freezing side and cooling side temperature sensors and flow sensors of the refrigeration room.

[0127] Traditional methods are all "forward construction" methods for sensor benchmark values. The estimation of benchmark values ​​depends on other devices or input parameters, and there is a large uncertainty. In addition, the multidimensional constraints of the system itself are not taken into account when constructing benchmark values. The method of the embodiment of the present invention proposes a "reverse judgment" method for benchmark values. By constructing a multidimensional logical association network between sensors such as temperature and flow, the sensor measurement values ​​are judged. Whether the multidimensional sensor true value logical association constraint relationship is met is used as the key criterion for judging whether the benchmark values ​​of each sensor are accurate and reliable. Only when they obtain the benchmark values ​​at the same time, the logical association is the most harmonious. Otherwise, it indicates that at least one sensor deviates from the benchmark value, and the sensors in the system need to be calibrated. The method of the embodiment of the present invention constructs the logical association between parameters such as temperature, flow and power through the physical characteristics of the refrigeration room water system, providing high-quality data support for the optimized operation of the efficient room.

[0128] A specific example is provided below.

[0129] The temperature measurement values ​​of the temperature sensors on the refrigeration system side of the three chillers in the high-efficiency refrigeration room and the flow measurement values ​​of the flow sensors are selected for true value judgment. The chilled water return main pipe and the three chilled water return branches are equipped with temperature sensors and flow sensors, and the chilled water supply branches and the three chilled water supply main pipes are equipped with temperature sensors. The measurement data of the sensors in the refrigeration room within the preset time period are collected to construct a steady-state measurement data set. The measurement values ​​at the same time are selected from the steady-state measurement data set for judgment, and the inconsistency value is calculated using equations (4) to (6). The judgment results are shown in Table 1.

[0130] Table 1 True value judgment results of chilled water system sensors in refrigeration room

[0131]

[0132]

[0133] The basic principles, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above specific embodiments, and the descriptions in the above specific embodiments and the specification are only for further illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed for protection.

Claims

1. A method for determining the true value of a refrigeration room sensor based on multi-dimensional constraints, characterized in that: The following steps are involved: Step 10, establishing a multi-dimensional sensor truth value logical association constraint relationship according to the sensor layout structure in the refrigeration room; Step 20, constructing an inconsistency function group according to the multi-dimensional sensor truth value logical association constraint relationship; Step 30, collecting measurement data of sensors in the refrigeration room within a preset time period to construct a steady-state measurement data set; Step 40, using the inconsistency function group to calculate the associated inconsistency values ​​of the measurement data in the steady-state measurement data set, if all the associated inconsistency values ​​of the measurement data are less than the inconsistency threshold, the measurement data is considered to be a true value; The multi-dimensional sensor truth value logic association constraint relationship includes temperature consistency association constraint, mass conservation association constraint and energy conservation association constraint; In step 10, the sensor arrangement structure in the refrigeration room is as follows: a temperature sensor and a flow sensor are provided on the chilled water return main pipe and the chilled water return branch pipe, a temperature sensor is provided on the chilled water supply branch pipe and the chilled water supply main pipe; a flow sensor is provided on the chilled water bypass pipe between the chilled water supply main pipe and the chilled water return main pipe; Establish the consistency constraint relationship of chilled water return temperature shown in formula (1): Formula (1) In the formula, Indicates The chilled water return temperature of each chiller, Indicates the number of chillers; Establish the chilled water quality conservation constraint relationship shown in formula (2): Formula (2) In the formula, Indicates the chilled water flow rate of the chilled water main. Indicates The chilled water flow rate of the chilled water branch pipe where the chiller is located, Indicates the chilled water flow rate of the chilled water bypass pipe; Establish the associated constraint relationship of chilled water energy conservation shown in formula (3): Formula (3) In the formula, Indicates the chilled water temperature of the chilled water supply main. Indicates the chilled water temperature of the chilled water return main. Indicates The chilled water supply temperature of each chiller, Represents the average value of the chilled water supply temperature of all chillers, Indicates the average value of the chilled water return temperature of all chillers; The consistency association constraint relationship of chilled water return temperature, the conservation association constraint relationship of chilled water quality and the conservation association constraint relationship of chilled water energy constitute the multi-dimensional sensor truth value logic association constraint relationship; In step 10, according to the chilled water return temperature consistency association constraint relationship, the chilled water return temperature inconsistency function shown in formula (4) is constructed: Formula (4) In the formula, Indicates the inconsistency value of the chilled water return temperature. Indicates the average value of the chilled water return temperature of all chillers; In step 10, according to the associated constraint relationship of the chilled water quality conservation, the inconsistency function of the chilled water quality conservation shown in equation (5) is constructed: Formula (5) In the formula, Indicates the inconsistency value of chilled water quality conservation; In step 20, according to the associated constraint relationship of chilled water energy conservation, the chilled water energy conservation inconsistency function shown in formula (6) is constructed: Formula (6) In the formula, It indicates the inconsistency value of energy conservation of chilled water; Alternatively, in step 10, the sensor arrangement structure in the refrigeration room is as follows: a temperature sensor and a flow sensor are provided on the cooling water return main pipe and the cooling water return branch pipe, a temperature sensor is provided on the cooling water supply branch pipe and the cooling water return main pipe; a flow sensor is provided on the cooling water bypass pipe between the cooling water supply main pipe and the cooling water return main pipe; Establish the cooling water return temperature consistency constraint relationship shown in formula (7): Formula (7) In the formula, Indicates the cooling water temperature of the cooling water return main. Indicates The cooling water return temperature of each chiller, Indicates the number of chillers; Establish the cooling water quality conservation constraint relationship shown in formula (8): Formula (8) In the formula, Indicates the cooling water flow rate of the cooling water main. Indicates The cooling water flow rate of the cooling water branch pipe where the chiller is located, Indicates the cooling water flow rate of the cooling water bypass pipe; Establish the cooling water energy conservation constraint relationship shown in formula (9): Formula (9) In the formula, Indicates the cooling water temperature of the cooling water supply main. Indicates the cooling water temperature of the cooling water return main. Indicates The cooling water supply temperature of each chiller, Represents the average cooling water supply temperature of all chillers, Indicates the average cooling water return temperature of all chillers; The correlation constraint relationship of cooling water return temperature consistency, cooling water quality conservation and cooling water energy conservation constitute the multi-dimensional sensor truth value logic correlation constraint relationship; In step 20, according to the cooling water return temperature consistency association constraint relationship, the cooling water return temperature inconsistency function shown in formula (10) is constructed: Formula (10) In the formula, Indicates the cooling water return temperature inconsistency value. Indicates the average value of the chilled water return temperature of all chillers; According to the associated constraint relationship of cooling water quality conservation, the inconsistency function of cooling water quality conservation shown in formula (11) is constructed: Formula (11) In the formula, Indicates the inconsistency value of cooling water quality conservation; According to the associated constraint relationship of cooling water energy conservation, the cooling water energy conservation inconsistency function shown in formula (12) is constructed: Formula (12) In the formula, Indicates the inconsistency value of cooling water energy conservation.

2. According to the method for determining the true value of a refrigeration room sensor based on multi-dimensional constraints in claim 1, it is characterized in that: The step 30 specifically includes: Step 301, collecting measurement data of sensors in the refrigeration room within a preset time period, and using a rolling time window to pre-process the measurement data of each sensor in different time periods; Step 302, using formula (13) to calculate the coefficient of variation of the data of each sensor in each time period: Formula (13) In the formula, represents the coefficient of variation of the data, represents the standard deviation of the data, represents the average value; Step 303 : Select the measurement data of the time period in which the data variation coefficients of all sensors are less than the coefficient threshold to form the steady-state measurement data.

3. The method for determining the true value of a refrigeration room sensor based on multi-dimensional constraints according to claim 1 is characterized in that: The inconsistency threshold is 5%.

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