Air-Conditioning Failure Diagnosis Using Dynamic Actuator Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current failure diagnosis systems for air-conditioning apparatuses suffer from low accuracy during normal operation, leading to frequent unnecessary failure diagnosis operations, increased power consumption, and reduced comfort, as they rely on limited data and fixed actuator control, which hampers efficiency and accuracy.
Innovation Solution
A failure diagnosis system that includes a state detection unit, a controller, and an abnormality diagnosis unit to detect and diagnose abnormalities in the refrigerant circuit by changing actuator control values and analyzing state and control data before and after the change, enabling precise identification of abnormality causes during normal operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If failure diagnosis operation is performed frequently to improve diagnosis accuracy, then diagnosis accuracy is improved, but power consumption increases and comfort is reduced
Solution Approach 1:
The system performs preliminary diagnosis during normal operation using a small amount of data to assess the likelihood of failure. Only when the preliminary diagnosis indicates a high probability of failure does the system proceed to full failure diagnosis operation, thereby avoiding unnecessary frequent diagnoses and reducing power consumption while maintaining diagnosis accuracy when needed.
2Measurement precision
If fixed actuator control is applied during failure diagnosis to improve measurement accuracy, then measurement precision is improved, but comfort and power efficiency deteriorate
Solution Approach 1:
The system dynamically adjusts actuator control based on the diagnosis stage. During preliminary diagnosis, normal dynamic actuator control is maintained to preserve comfort. During full failure diagnosis operation, fixed actuator control is applied only when necessary for accurate measurement, allowing the system to balance measurement precision with comfort and power efficiency.
3Reliability
If preliminary diagnosis is adjusted to be easily determined to improve detection sensitivity, then detection sensitivity is improved, but false positives increase leading to unnecessary full diagnosis operations
Solution Approach 1:
The system uses feedback from preliminary diagnosis results to determine whether to proceed to full failure diagnosis operation. The preliminary diagnosis detects potential issues with appropriate sensitivity, and the feedback mechanism ensures that full diagnosis is only triggered when necessary, balancing detection sensitivity with diagnosis efficiency by avoiding unnecessary full diagnosis operations.
Data Source
AI summary
A failure diagnosis system diagnoses the state of an air-conditioning apparatus having a refrigerant circuit in which refrigerant circulates. The failure diagnosis system has an abnormality diagnosis unit that performs normal-operation abnormality diagnosis for determining whether or not there is an abnormality in the air-conditioning apparatus by using state data and control data during normal operation of the air-conditioning apparatus. If the abnormality diagnosis unit determines that there is an abnormality, it changes a control value for an actuator of the air-conditioning apparatus and acquires state data and control data. Then, the abnormality diagnosis unit performs abnormality-cause identification diagnosis for identifying the cause of the abnormality in the air-conditioning apparatus by using the state data and the control data acquired before the change of the control value and the state data and the control data acquired after the change of the control value.