CN-121996939-A - Air conditioning system operation evaluation and diagnosis method and system thereof

CN121996939ACN 121996939 ACN121996939 ACN 121996939ACN-121996939-A

Abstract

The invention provides an air conditioning system operation evaluation and diagnosis method and a system thereof, comprising the following steps of obtaining subentry energy consumption historical data of an air conditioning system to be evaluated to form a time domain data sequence; the method comprises the steps of carrying out Fourier transformation on a time domain data sequence to convert the time domain data sequence into frequency domain data, establishing a frequency domain evaluation diagnosis model and evaluation index of the sub-energy consumption of an air conditioning system, establishing a grading standard of the operation evaluation and diagnosis of the air conditioning system based on the evaluation index, establishing an air conditioning system operation evaluation and diagnosis quadrant region, obtaining the distribution relation of amplitude and frequency according to a frequency domain data result, calculating a periodic fluctuation characteristic intensity value and a variation coefficient of the sub-energy consumption based on the evaluation diagnosis model and the evaluation index, and evaluating the operation state of the air conditioning system and diagnosing faults according to the determined grading standard and quadrant region. The method realizes comprehensive evaluation and accurate fault diagnosis of the running state of the air conditioning system, improves the running efficiency of the air conditioning system and reduces the energy consumption.

Inventors

LIU ZHAOHUI
LI ZHENYU
PAN XI
CHEN HAO
SONG JIALING

Assignees

上海建工集团股份有限公司

Dates

Publication Date: 20260508
Application Date: 20251218

Claims (10)

1. An air conditioning system operation evaluation and diagnosis method, comprising the steps of: S1, acquiring subentry energy consumption historical data of an air conditioning system to be evaluated, and forming a time domain data sequence; S2, carrying out Fourier transform on the time domain data sequence to convert the time domain data sequence into frequency domain data; s3, establishing a frequency domain evaluation diagnosis model of the air conditioning system sub-item energy consumption and corresponding evaluation indexes; S4, establishing a grading standard of air conditioning system operation evaluation and diagnosis based on the evaluation index, and constructing an air conditioning system operation evaluation and diagnosis quadrant region for diagnosis; S5, according to the frequency domain data result obtained in the step S2, acquiring the distribution relation of the amplitude and the frequency, calculating the periodic fluctuation characteristic intensity value and the variation coefficient of the sub-energy consumption based on the evaluation diagnosis model and the evaluation index in the step S3, and evaluating and diagnosing the running state of the air conditioning system according to the grading standard and the quadrant area determined in the step S4.
2. The method for evaluating and diagnosing operation of an air conditioning system according to claim 1, wherein the sub-term energy consumption history data of the air conditioning system includes historical energy consumption data of a chiller/heat pump unit, a chilled water pump/hot water pump, a cooling tower, an air conditioning end fan coil/air handling unit, and a fresh air system.
3. The air conditioning system operation evaluation and diagnosis method according to claim 2, wherein the sampling interval of the historical energy consumption data is 1 hour, and the sampling time exceeds 8760 hours.
4. The air conditioning system operation evaluation and diagnosis method according to claim 1, wherein the fourier transform in step S2 employs a fast fourier transform method.
5. The air conditioning system operation evaluation and diagnosis method according to claim 1, wherein the evaluation index includes at least two of: Evaluating a first index of the operation matching performance of the air conditioning system, wherein the first index is the fluctuation characteristic intensity sigma k,i of each sub-energy consumption period of the air conditioning system; And evaluating a second index of the air conditioning system operation matching performance, wherein the second index is a variation coefficient C V,i of the characteristic intensity of the air conditioning system sub-energy consumption period fluctuation.
6. The air conditioning system operation evaluation and diagnosis method according to claim 5, wherein the step S4 is a step limit of the second index as a step criterion of the air conditioning system operation evaluation; And step S4, the grading standard of the operation diagnosis of the air conditioning system is the grading limit value of the first index after normalization processing.
7. The air conditioning system operation evaluation and diagnosis method according to claim 6, wherein the classification limit of the second index includes: a first limit of 0< C V,i < 0.1; the second limit is 0.1< C V,i < 0.3; The third limit is 0.3< C V,i < 0.5; a fourth limit of C V,i >0.5; the grading limit value of the first index after normalization processing comprises: A first limit of 0< sigma' k,i < 0.4; a second limit of 0.4< sigma' k,i < 0.8; a third limit of 0.8< sigma' k,i < 1; Wherein sigma' k,i is the characteristic intensity of energy consumption normalized cycle fluctuation of each sub-item of the air conditioning system.
8. The air conditioning system operation evaluation and diagnosis method according to claim 1, wherein the period for which the cycle fluctuation characteristic intensity value is calculated in step S5 includes 1 year, 1 week and 1 day.
9. The method for evaluating and diagnosing operation of an air conditioning system according to claim 1, wherein in step S5, the normalization processing method for the periodic fluctuation characteristic intensity value is as follows: Under the same period, the normalized periodic fluctuation characteristic intensity sigma' k,i of each sub-item energy consumption is equal to the ratio of the periodic fluctuation characteristic intensity sigma k,i of the sub-item energy consumption to the periodic fluctuation characteristic intensity maximum value max (sigma k,i ) of all N sub-item energy consumption under the corresponding period, wherein N is the total amount of the sub-item energy consumption of the air conditioning system.
10. An air conditioning system operation evaluation and diagnostic system, comprising: The data acquisition module is used for acquiring the subentry energy consumption historical data of the air conditioning system to be evaluated to form a time domain data sequence; The frequency domain conversion module is in communication connection with the data acquisition module and is used for carrying out Fourier transform on the time domain data sequence so as to convert the time domain data sequence into frequency domain data; The evaluation model construction module is in communication connection with the frequency domain conversion module and is used for establishing a frequency domain evaluation diagnosis model of the air conditioning system sub-energy consumption and corresponding evaluation indexes; the hierarchical diagnosis area construction module is in communication connection with the evaluation model construction module and is used for establishing a hierarchical standard of air conditioning system operation evaluation and diagnosis based on the evaluation index and establishing an air conditioning system operation evaluation and diagnosis quadrant area for diagnosis; The evaluation diagnosis execution module is respectively in communication connection with the frequency domain conversion module, the evaluation model construction module and the hierarchical diagnosis area construction module, and is used for acquiring the distribution relation of the amplitude and the frequency according to the frequency domain data result obtained by the frequency domain conversion module, calculating the periodic fluctuation characteristic intensity value and the variation coefficient of the sub-term energy consumption based on the evaluation diagnosis model and the evaluation index of the evaluation model construction module, and evaluating and diagnosing the running state of the air conditioning system according to the hierarchical standard and the quadrant area determined by the hierarchical diagnosis area construction module.

Description

Air conditioning system operation evaluation and diagnosis method and system thereof Technical Field The invention belongs to the technical field of operation evaluation of air conditioning systems, and particularly relates to an operation evaluation and diagnosis method and system for an air conditioning system. Background Centralized air conditioning systems are the core systems in modern public buildings and industrial facilities that maintain environmental comfort and meet process demands, with energy consumption generally accounting for up to 40% to 60% of the total energy consumption of the building. Under the national 'double carbon' strategic background, the fine operation management and energy efficiency improvement of the system become key tasks in the building energy-saving field. Air conditioning systems are typically complex systems whose operation covers the coordinated operation of multiple devices such as chiller/heat pump units, chilled/chilled water pumps, cooling towers, air conditioning terminals (e.g., fan coils, air handling units), and fresh air systems. The running state of the system is influenced by multiple dynamic factor coupling such as building load, outdoor weather conditions, internal regulation strategies and the like. The characteristics of multiple devices, multiple links and strong coupling enable the operation matching performance (namely the mercy and efficiency of cooperative operation under different working conditions) among all devices in the system to become the core for determining the overall energy efficiency. In actual operation, the problems of mismatching of operations such as 'large Mala trolley', hydraulic imbalance, cold and hot offset and the like are common, and a large amount of energy sources are wasted. In the prior art, the operation evaluation and diagnosis of an air conditioning system are mostly dependent on the monitoring of various operation parameters such as temperature, pressure, flow and the like. However, the method has obvious limitations that firstly, a plurality of sensors are required to be installed, so that the cost is high and the implementation is complex, and secondly, an effective means for quantifying the running matching between devices from the whole system level is lacking. Due to complex implementation and high cost, the existing method is difficult to widely apply and cannot provide effective support for the normalized operation optimization of the system. Disclosure of Invention The invention provides an air conditioning system operation evaluation and diagnosis method and a system thereof, which realize comprehensive evaluation and accurate fault diagnosis of the operation state of the air conditioning system, improve the operation efficiency of the air conditioning system and reduce the energy consumption. The technical scheme of the invention is as follows: An air conditioning system operation evaluation and diagnosis method comprises the following steps: S1, acquiring subentry energy consumption historical data of an air conditioning system to be evaluated, and forming a time domain data sequence; S2, carrying out Fourier transform on the time domain data sequence to convert the time domain data sequence into frequency domain data; s3, establishing a frequency domain evaluation diagnosis model of the air conditioning system sub-item energy consumption and corresponding evaluation indexes; S4, establishing a grading standard of air conditioning system operation evaluation and diagnosis based on the evaluation index, and constructing an air conditioning system operation evaluation and diagnosis quadrant region for diagnosis; S5, according to the frequency domain data result obtained in the step S2, acquiring the distribution relation of the amplitude and the frequency, calculating the periodic fluctuation characteristic intensity value and the variation coefficient of the sub-energy consumption based on the evaluation diagnosis model and the evaluation index in the step S3, and evaluating and diagnosing the running state of the air conditioning system according to the grading standard and the quadrant area determined in the step S4. Further, in the operation evaluation and diagnosis method of the air conditioning system, the sub-term energy consumption historical data of the air conditioning system comprises historical energy consumption data of a water chilling unit/heat pump unit, a chilled water pump/cooling water pump/hot water pump, a cooling tower, an air conditioning terminal fan coil/air processing unit and a fresh air system. Further, in the air conditioning system operation evaluation and diagnosis method, the sampling interval of the historical energy consumption data is 1 hour, and the sampling time is more than 8760 hours. Further, in the operation evaluation and diagnosis method of the air conditioning system, the fourier transform in the step S2 is a fast fourier transform method. Further, in the air condit