2008-02-20 - Industrial motors use about 30 percent of electricity produced in the world, but fewer than 10 percent are equipped with the most efficient speed control that exists. The result is that the motors are run at full speed and then throttled to reduce output – similar to driving a car with one foot on the accelerator and the other on the brake.
By
ABB Communications
ABB has a solution that saves electricity, cuts costs and helps slow the depletion of energy resources.
About three-quarters of all motors are used to run pumps, fans or compressors, applications where speed can often be reduced and energy, saved.
|
The new ACS 5000 frequency converter removes concerns about motor overheating and compatibility.
This is accomplished with frequency converters, which adapt motor speed to match the required pressure or flow, instead of allowing them to run at full speed. The problem is that in 90 per cent of cases, industries are still running machines at full speed, without benefit of converter technology. ABB set out to determine why.
Of course the converters cost money, much of which will be repaid in energy savings. Customers frequently cite three other factors that dissuade them from making the investment in this greener method of speed control.
They say they have concerns about converter reliability, as well as its capacity to reach the high voltages needed at the highest speeds of medium-voltage motors. Customers also say they are concerned about the disturbances that converters might cause in their electrical systems, especially the mechanical consequences where motors do not turn smoothly, but send jolts and bumps through the system, known as torque ripple.
90 per cent of industrial motors are operating at full speed, without the most efficient method of speed control: the frequency converter
The ABB solution
ABB’s ACS 5000 power frequency converter answers these concerns.
Its five-level switch, replacing converter switches with two or three levels, ensures the highest levels of voltage and motor output at 6 kV, rather than 2.3 kV, while creating a wave form that more closely approximates electricity that is generated 'traditionally,' as for motors operated at a fixed speed.
The improved wave form is more synchronous with the motor, reduces the torque ripple, and protects the motor from overheating.
Finally the innovation draws largely on proven concepts already in use for greater reliability. The result is a longer-lived motor whose speed is adjusted as needed – for considerable energy savings.