The application of FD5000 in ball mills
In the mining industry, grinding processes have long relied on ball mills. These mills typically use hydraulic couplings for startup. This method draws high inrush current and creates large impacts on both equipment and the power grid. Under fixed power frequency operation, the mills often over-grind materials. Grinding cycles take a long time and operate at low efficiency. As a result, energy consumption per unit of product remains high.
An overseas company needed to add a new ball mill system. Their existing ball mill system used a high-voltage VFD manufactured by ABB. The company decided to reduce costs and improve efficiency for their ball mill system. They wanted to lower production costs and increase the mill's operating efficiency.
The rotational speed of the ball mill cylinder greatly affects the crushing performance and mill output. When the cylinder rotates too slowly, the cylinder cannot lift the grinding media to an adequate height. As a result, the grinding media delivers a very weak impact on the material.
To reduce production costs and improve the operating efficiency of the ball mill system, the company decided to retrofit the ball mill using a high-voltage VFD.
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Motor parameters |
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Model |
YR800-8/1180 |
Power |
800kW |
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Rated voltage |
10kV |
Rated current |
56.2A |
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Power factor |
0.86 |
Rated frequency |
50Hz |
To reduce system impact and energy loss during switching between VFD operation and line operation, the customer chose a one-drive-to-one-motor solution with automatic bumpless transfer. The specific model is FD5000-10/1000F-1A.
Application characteristics
Seamless switching function: Employing phase-locked loop (PLL) technology, the inverter switches the motor to the mains power supply with minimal current when the inverter's output voltage is synchronized with the mains voltage. The switching current does not exceed 1.5 times the rated current, fully meeting the soft-start requirements of high-power motors.
Comprehensive protection and diagnostic functions: The FD5000 series incorporates comprehensive protection and diagnostic functions, ensuring the motor system can respond promptly to abnormal situations, reducing maintenance costs.
Unit DC voltage detection function: Real-time display of the system's DC voltage enables optimized output voltage control, reducing harmonic content, ensuring output voltage accuracy, improving system control performance, and providing maintenance personnel with a comprehensive understanding of the power unit's operating status.
Automatic output voltage regulation technology: The inverter monitors the bus voltage of each unit in real time and adjusts the output voltage accordingly, achieving automatic voltage regulation.
