Electricity + Control May 2018

round up

DRIVES, MOTORS + SWITCHGEAR

Energy saving thanks to regenerative braking

the annual energy consumption of four German households. Non-linear electrical loads, also including variable speed drives, cause harmonics leading to unwanted voltage and current distortions in the net- works. These harmonics result in unreliable operation and can heat other loads such as motors, transformers and other electrical equipment excessively. This requires additional cooling, causes energy loss and in the worst case pre-ma- ture failure. Although additional electrical filters may attenuate such harmonics, it is however preferable not to allow them to be created at all. This is exactly what ABB's new variable speed drives do, they prevent harmonics before they appear. ACS880 can control co- sine phi of the fundamental to unity under all load conditions optimizing reactive pow- er and fully meets harmonics standards such as IEEE519, IEC61000-3-12 and G5/4. The new ACS880 regenerative drives fea-

Recovered energy is ‘clean’ and has a high quality. It can be used by other loads in- creasing plant efficiency significantly. The new generation of ABB industrial drives is able to control cosine phi of the fundamen- tal to unity under all load conditions so that the reactive power and energy consump- tion are optimized. The braking energy dissipated as heat in traditional methods such as resistor and mechanical braking usually requires addi- tional cooling. Reduced heat dissipation due to regen- erative braking considerably reduces the need for air conditioning of the electrical room. The following example illustrates how much energy can be saved by means of such solutions: For a crane used in waste handling with a 55 kW hoisting motor, a 9 kW long travel motor and a 4,5 kW trolley motor and a regenerative drive annual sav- ings total approx. 15,6 MWh – or €2 300. This reduction by 32% corresponds to

ture high immunity to system disturbances and can stabilize and even improve motor voltage in case of instable supply. This en- sures reliable operation even if supply volt- age drops below the normal value. Since there is no need for external brake components, ABB's regenerative drives are significantly more compact than con- ventional solutions. Reduced engineering and material costs and a smaller footprint in the electrical room deliver considerable savings potential regarding the cabinet building costs. The wall-mounted ACS880-11, the ACS880-14 modules and the cabinet-built ACS880-17 are equipped with all the re- quired components installed in a compact enclosure ready for connection. This facilitates and accelerates cabinet installation additionally because there is no need for the subsequent wiring of various components. Enquiries: Email media.relations@ch.abb.com