1th November, the electric locomotive of the permanent magnet direct drive traction system that is independently developed by CRRC Yongji Electric Co.,Ltd., was officially launched in Datong, Shanxi. In China, this is the first high-power AC drive electric locomotive using the permanent magnet direct drive technology. As a new generation technology, the permanent magnet direct drive traction system, which is developed by CRRC Yongji Electric Co.,Ltd., is more efficient and energy-saving, and has brought the revolutionary changes to the development of the rail transit.
For a long time, the permanent magnet synchronous motor (PMSM) has become the research trend of new generation rail transit equipment due to its advantages of high-power density, high-power factor and high overload capacity. It is milestone significance that the permanent magnet direct drive traction system has implemented the application in the high-power AC drive electric locomotives. This system uses the permanent magnet synchronous motor direct drive wheelsets technology and eliminates the gear box. The transmission mode has the advantages of simple structure, high transmission efficiency, green energy saving, etc., and is the development trend of the next generation traction transmission system.
Since 2006, CRRC Yongji Electric Co.,Ltd. has been developing the research and development of permanent magnet traction system. It has made major technological breakthroughs and implemented mass application in the fields of electric locomotives, EMU, urban rail transit and wind power generation. It has accumulated a large number of R&D experience and operational data. The research and development of direct drive permanent magnet electric drive system began in 2014. It took five years to use the advanced simulation platform to focus on the key technologies of direct-drive permanent magnet system, and to overcome the series of core technological problems, including electromagnetic design and cooling technology of high-power permanent magnet motor, low-speed large torque and high-speed weak magnetic control of direct-drive permanent magnet motor, etc. At the same time, on the full-power test platform, the reliability of the direct-drive permanent magnet system has been fully tested and verified, and the demagnetization of permanent magnet motor and the reverse electromotive force of the permanent magnet concerned by experts in the industry have been fully studied and tested, so as to realize the high reliability and stability of the direct drive permanent systems.