Pump Motor Idling Detection Using PWM Voltage Thresholds
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing motor idling detection methods require high-precision current sensors, which are costly and prone to errors, especially when motors drive pumps that draw and discharge liquids, leading to potential performance issues and reduced lifespan.
Innovation Solution
A motor idling detection device that acquires motor voltage and compares it with an idling determination threshold value to determine if the motor is idling, utilizing PWM-control to calculate motor voltage from duty ratio and power supply voltage, eliminating the need for high-precision current sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high-precision current sensors are used to detect motor idling, then detection accuracy is improved, but device cost and complexity increase
Solution Approach 1:
The patent replaces the mechanical/electrical measurement system (current sensors) with an observation-based system. Instead of physically measuring current to detect motor idling, the system observes whether the motor's rotation speed matches the pump's rotation speed. This substitution eliminates the need for high-precision current sensors while maintaining detection accuracy.
Solution Approach 2:
The patent introduces an intermediary detection method: rather than directly measuring current to determine motor idling, it uses the relationship between motor rotation speed and pump rotation speed as an intermediary indicator. If the motor rotation speed differs from the pump rotation speed, it indicates the motor is not properly driving the pump, suggesting idling or malfunction.
2Measurement precision
If high-precision current sensors are used to detect motor idling, then detection accuracy is improved, but reliability decreases due to sensor errors
Solution Approach 1:
The patent replaces the unreliable current sensor-based detection system with a more reliable observation-based system. By monitoring motor rotation speed and comparing it with pump rotation speed, the system avoids the errors and failures inherent in high-precision current sensors, thereby improving overall detection reliability.
Solution Approach 2:
The patent implements a feedback mechanism where the control unit continuously monitors the relationship between motor rotation speed and pump rotation speed. This feedback loop allows the system to detect motor idling conditions reliably and trigger appropriate error handling, improving the overall reliability of the detection system.
3Reliability
If motor idling is not detected, then pump performance deteriorates, but detection requires complex high-precision sensors
Solution Approach 1:
The patent replaces the complex sensor-based detection system with a simpler observation-based system. By monitoring whether motor rotation speed matches pump rotation speed, the system can detect motor idling conditions that would otherwise go unnoticed, thereby preventing pump performance deterioration without requiring complex high-precision sensors.
Solution Approach 2:
The patent enables the system to self-detect motor idling conditions through its existing control unit and rotation speed monitoring capabilities. The control unit automatically compares motor and pump rotation speeds and triggers error handling when idling is detected, allowing the system to protect itself without additional complex detection hardware.
Data Source
AI summary
A motor idling detection device for detecting idling of a motor that drives a pump that draws in and discharges liquid includes an acquisition unit and an idling determination unit. The acquisition unit acquires a motor voltage applied to the motor. The idling determination unit compares the motor voltage acquired by the acquisition unit with an idling determination threshold value for determining whether the motor is idling, and determines whether the motor is idling or not based on a result of a comparison.