Harmonics have long been a problem in the Shanghai metro system leading, among other things, to the early and costly replacement of capacitors and other critical power equipment. Harmonic pollution is caused by the increasing use of devices like PCs, TVs and electronic office equipment that create distortion in the power distribution network.
The ABB solution protects the power network by filtering the harmonics that cause cables, motors and transformers to overheat, capacitors to fail, circuit breakers to trip and the network to become unstable and inefficient.
Significantly and of vital importance to Shanghai Metro, the solution enables power inverters to be installed in the metro’s 400 V power distribution network to further reduce energy consumption. One of the side effects of inverters is that they generate harmonics.
The ABB solution eliminates the harmonics while itself consuming minimal power, thus providing Shanghai Metro with a cost-effective and energy-efficient solution that improves power quality and network stability.
Shanghai is China's largest city with more than 20 million residents, and is one of the largest urban areas in the world. Shanghai Metro is the biggest urban rapid transit system in China and one of the newest and most rapidly expanding subway systems in the world.
It currently consists of eight lines and 162 stations and is used by more than three million passengers everyday.
ABB has been selected by Shanghai Metro on several occasions over the past few years to supply power equipment to secure the metro’s power quality and reliability. Solutions include gas insulated switchgear, power transformers, high voltage components and UniGear medium voltage switchgear.