Electric motors
Electric motors convert electrical energy into mechanical energy to operate industrial equipment by means of a rotating shaft.
In the Alicante industrial sector many processes are used and induction motors are very important due to fact that they are simple, cheap, economical and reliable.
Different factors determine the energy efficiency of an electric motor such as the efficiency of the motor, motor speed control, proper size and design, quality of the power supply, energy dissipation, mechanical transmission, maintenance and mechanical efficiency (pumps, ventilators, compressors, etc.).
ENERGY SAVING AND EFFICIENCY MEASURES
– Using high performance motors (Savings of more than 2%)
They are motors made with high quality materials whose energy efficiency is more than 90%. The European Commission establishes three levels of energy efficiency; EFF1 or IE2 High efficiency level motor, EFF2 or IE1 Improved efficiency level motor and EFF3 Standard efficiency level motor. The high efficiency motors consume less energy to produce the same power as a conventional induction electric motor.
It is only possible to market the EFF1 high efficiency motors at the moment.
– Installing variable frequency drives. (Saving more than 4%)
To control pumps and ventilators frequency converters/variable frequency drives are used to control the speed of the motor by modifying the frequency of the power supplied to the motor, so that it adapts to the load conditions.
Specifically, with regard to pumping fluids and ventilation, where the flow has to be regulated, a considerable amount of energy can be saved if the adjustment range that is required is relatively high and the operating hours of the unit are long.
– Choosing the motor. Operating point..
The sizing of the motors is very important. The maximum output obtained is between 75 and 85% of the rated load, output drops considerably as the load decreases, which means that oversizing has to be avoided.