1. Current and Power Monitoring
1. Current Method
Use an ammeter to monitor the motor stator current. If the current consistently exceeds the rated value by 10%-15%, it indicates an overload. If the current is significantly lower than normal (e.g., less than 70% of the no-load current), it may be idling.
An active power meter can assist in this determination: a sudden increase in power indicates an overload, while a sudden decrease in power may indicate idling.
2. Power Peak Point
When the power reaches its peak and then decreases, the load has exceeded the optimal level and the feed rate should be reduced.
2. Grinding Noise Detection (Electro-Ear Method)
Overload Characteristics
A dull, low-frequency sound indicates overfilling and the impact of the steel balls is being cushioned.
Idle Characteristics
A crisp, high-frequency sound indicates the steel balls directly impacting the drum.
When multiple units are in operation, be aware of signal interference.
3. Vibration Analysis
Vibration intensity increases when overloaded (accelerometer detection value exceeds 0.5 mm/s), while vibration decreases when idling. The vibration method is highly sensitive and unaffected by ambient noise.
IV. Comprehensive Judgment and Treatment
Overload Treatment: Reduce the feed rate, check the material particle size and moisture content, and clean any clogged baffles.
Idle Run Treatment: Check the feeding system for malfunctions and adjust the material-to-ball ratio to an acceptable range.
V. Automated Control Application
A fuzzy PID algorithm is used to coordinate control of multiple parameters, including current, grinding noise, and vibration, to adjust load in real time.
For example, a power plant in Xinjiang uses an intelligent grinding noise recognition system to achieve self-optimizing control and improve stability.
