Speed-Based Flow Device Diagnostic System
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing flow device diagnostic systems rely on physical volumetric flow sensors, which are not always effective in detecting output flow issues, such as blockages or leaks, and fail to differentiate between functioning and non-functioning flow devices without corresponding output flow.
Innovation Solution
A speed-based diagnostic system that uses a controller to command flow devices to a calibrated upper speed limit, then allows them to coast down to a lower speed limit, calculating the rate of change in speed to determine if it falls within a calibrated range, thereby diagnosing performance without flow sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If physical volumetric flow sensors are used to detect output flow, then flow measurement capability is improved, but device complexity and cost increase
Solution Approach 1:
The patent extracts the flow measurement function from physical flow sensors and implements it through speed-based monitoring of the flow device itself. By measuring the rotational speed of the pump or fan and analyzing its decay characteristics during coast-down, the system derives flow information without requiring separate flow sensing hardware.
Solution Approach 2:
The patent uses rotational speed as an intermediary parameter to infer flow conditions. Instead of directly measuring flow with complex sensors, the system measures speed (a simpler parameter) and uses the relationship between speed decay and flow resistance to determine actual flow output, effectively using speed as a mediator between the control system and flow conditions.
2Reliability
If physical volumetric flow sensors are used to differentiate functioning and non-functioning flow devices, then diagnostic accuracy is improved, but system cost and complexity increase
Solution Approach 1:
The flow device performs its own diagnostic function by monitoring its own speed characteristics. The control system analyzes the coast-down behavior of the flow device itself to determine whether it is functioning properly or blocked, eliminating the need for separate diagnostic sensors or systems.
Solution Approach 2:
The patent monitors changes in speed parameters during the coast-down phase to detect diagnostic information. By analyzing how the speed decays over time and comparing it to expected characteristics, the system can distinguish between a functioning device and one that is blocked or malfunctioning.
3Measurement precision
If flow sensors are installed in the system, then direct flow detection is improved, but ease of operation and maintenance deteriorate
Solution Approach 1:
The patent removes flow sensors from the fluid path and replaces them with speed sensing capability that is already integrated into the flow device's motor control system. This eliminates the need for additional sensors that would require installation, calibration, and maintenance in the fluid circulation system.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Enables accurate diagnosis of flow device performance by analyzing the rate of change in speed during the coast-down phase, effectively identifying issues like blockages or leaks without the need for physical sensors, ensuring reliable operation of fluid circulation systems.
Implementation Method 1
the speed of the flow device gradually decreases to a calibrated lower speed limit as friction acts on the flow device
Data Source
AI summary
A vehicle or other system includes a flow device, component, and controller. The controller executes a method of diagnosing flow performance in the vehicle/system. The flow device is a pump, blower, or fan. A calibrated upper speed limit is commanded from the flow device in response to detected enabling conditions. The device is turned off after maintaining the upper speed limit for a calibrated duration. The speed of the flow device is determined during a coast-down interval defined by a period between command of the upper speed limit and attaining a calibrated lower speed limit. An absolute rate of change of the speed over the coast-down interval is calculated, with the controller executing a control action when a maximum absolute slope of the calculated rate of change falls outside of a calibrated range during the coast-down interval.