Work on the project started in 2014 and was based on Zhuzhou CRRC Times Electric’s experience with permanent magnet synchronous traction systems. The overall design was completed in early 2015. Trials started in March this year with a train fitted with permanent magnet direct-drive traction motors and involved performance, adhesion and dynamic tests. By July 7 the train had completed 12 trouble-free examinations.
The company says that a traction system accounts for between 40 and 50% of a metro network’s energy consumption and the test results showed that the permanent magnet direct-drive traction system reduced traction energy consumption by 15%. This saving could double if the maximum amount of energy regeneration is achieved. Traction motor noise was also reduced by 15dB to 87dB compared with a conventional traction system.