A brief analysis of the application of high-efficiency motors in belt conveyors

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When transporting materials, belt conveyors use high-efficiency motors to drive the mechanical components, thereby enabling the conveying equipment to move materials more quickly. The conveyor belt of the belt conveyor can be selected according to the requirements of different processes, and it can also operate in various modes such as continuous operation, intermittent operation, and variable-speed operation. The conveyor system is designed using various forms such as straight sections, curves, and slopes, depending on the specific conditions. With the development of various industries and market demands today, high-efficiency motors are being used more and more widely in belt conveyors. Conveyor belts equipped with high-efficiency motors experience losses that are about 20% lower compared to motors of current design; whereas those using ultra-high-efficiency motors have losses that are around 30% lower than those of currently available motors. China and the EU classify the efficiency of small and medium-sized three-phase asynchronous motors into three efficiency grades: Grade 1 efficiency and Grade 2 efficiency. Mandatory regulations require that motors with an efficiency lower than Grade 3 cannot be produced or sold. When motors leave the factory, they must be fitted with efficiency grade labels in a standardized format. The rated power for energy efficiency class 1 ranges from 3 kW to 315 kW, while that for energy efficiency classes 2 and 3 ranges from 0.55 kW to 315 kW. The number of poles in these motors is usually between two and six, and they are explosion-proof motors. The production, sales, and use of high-efficiency motors have little impact on increasing the costs of the drive systems in belt conveyors. According to investigations, over the lifetime of a belt conveyor motor, operating costs account for 92 percent, the purchase cost constitutes 7 percent, and maintenance costs are only 1 percent. If the efficiency of the motor is improved, the savings in electricity costs will far exceed the cost of purchasing a more efficient motor. Although high-efficiency asynchronous motors have a high efficiency at their rated points, they operate under light loads, resulting in relatively lower efficiency; they also have certain drawbacks. Rare-earth permanent magnet synchronous motors do not suffer from these problems. With the continuous advancement of science, it is believed that rare-earth permanent magnet synchronous motors will be used more widely in the coming years.