1.Introduction

For a long time, the ball mill is generally used to grind raw materials in the mining grinding process, and the hydraulic coupler is generally used to start, and the starting current has a large impact on the equipment and the power grid. At the same time, the power frequency is easy to cause excessive grinding of materials, long grinding cycle, low grinding efficiency, and large power consumption per unit product. This promotes the development of a ball mill control system with smooth start, high grinding efficiency, large output and low energy consumption.

2.Shortcoming

The starting impact is large and difficult to start: make the power frequency start, the impact current is as high as 6 to 8 times.
High energy consumption: The use of power frequency operation, the speed can not be adjusted, resulting in energy waste.
The working environment is complex: the on-site charged dust and corrosive gases are diffuse, which has a great impact on electronic equipment.

3.Solution

Motor rated voltage 690V, rated power 630kW. FGI is equipped with a high-performance vector inverter model FD300 series low frequency inverter. The frequency converter has large low frequency rotation and can adapt to complex power grid environment. At the same time, it also has a strong current impulse suppression ability, in the case of a large range of load fluctuations, but also to ensure safe and stable operation; In addition, it is also equipped with a perfect motor drive protection function, including overload, overcurrent, overvoltage, undervoltage, short circuit, phase loss and power failure and other protective measures.

The use of frequency converter to drive the ball mill can make the ball mill system start smoothly, higher grinding efficiency, higher output and lower energy consumption.

4.Application performance

FD300 series low frequency inverter has soft start function and high overload capability, which can reduce the impact on the power grid and electrical equipment, and the load changes frequently in the process of speed regulation.
Use excellent torque boost control algorithm, low frequency output full torque, start and stop smoothly.
FD300 series low frequency inverter uses fieldbus technology, real-time display of equipment status, to achieve control automation and monitoring intelligence, less human.
The product has a high protection ability to enhance the ability of equipment to withstand harsh environments.