Fan Speed Control via PWM Duty Ratio Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing heat-dissipating fan control systems rely on predetermined fan-temperature curves that fail to accurately reflect actual operating environments and cannot adjust for slight variations in electronic device characteristics, leading to non-linear rotational speed control and inability to monitor or repair fan performance.
Innovation Solution
A system comprising an analyzing module to analyze the relation between PWM duty ratio and fan rotational speed, and a compensating module to generate a compensating result based on this analysis and temperature proportion, allowing for dynamic adjustment of PWM duty ratio to optimize fan rotational speed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If predetermined fixed fan-temperature curves are provided for user selection, then the user can control fan rotational speed according to different operating requirements, but the curves cannot accurately reflect actual operating environments and cannot adjust for variations in electronic device characteristics
Solution Approach 1:
The system measures the actual rotational speed of the fan at different PWM duty ratios, compares it with the expected linear relationship, and generates compensating data to correct deviations. This feedback mechanism enables the system to adapt to actual operating conditions and device variations while maintaining accurate temperature-speed control.
Solution Approach 2:
The system changes the PWM duty ratio parameter to control fan speed and uses compensating data to adjust the relationship between duty ratio and rotational speed. By modifying these parameters based on actual measurements, the system achieves accurate adaptation to different operating environments and device characteristics.
2Temperature
If the rotational speed of the fan is increased when temperature is raised to accelerate heat dissipation, then heat dissipation performance is improved, but the control process becomes non-linear due to variations in machine constitution and manufacture inaccuracies
Solution Approach 1:
The system measures actual fan rotational speed at different PWM duty ratios and uses this feedback to generate compensating data that corrects non-linearities. This allows the system to maintain stable and accurate temperature-speed control relationships despite variations in machine constitution and manufacturing inaccuracies.
Solution Approach 2:
The system dynamically adjusts the PWM duty ratio based on actual fan performance measurements rather than using fixed predetermined curves. This dynamic adaptation allows the control relationship to remain linear and accurate across different operating conditions and device variations.
3Ease of operation
If conventional fan control methods are used with predetermined curves, then the system is simple to operate, but the user cannot monitor or determine whether fan control performance matches production settings
Solution Approach 1:
The system automatically measures fan rotational speed, compares it with expected values, and generates compensating data without requiring user intervention. This feedback mechanism provides continuous monitoring of fan performance while maintaining simple operation, eliminating the need for users to manually verify control accuracy.
Solution Approach 2:
The system performs self-diagnosis and self-correction by automatically measuring fan performance, generating compensating data, and adjusting control parameters. This self-service capability allows the system to monitor and maintain optimal fan performance without requiring user knowledge or intervention, preserving both simplicity and monitoring capability.
Data Source
AI summary
A system for compensating the characteristics of a fan, applied to a heat-dissipating fan of an electronic device. This system comprises of an analyzing module for analyzing the relation between the duty ratio of pulse width modulation (PWM) and the rotational speed of the fan to generate analyzing data, and a compensating module for generating compensating data basing on the analyzing data and a specific proportion relation between the temperature and the duty ratio of PWM.