The first permanent magnet direct-drive WK-55 electric shovel is being assembled at the equipment maintenance center of Zhunneng Group's Ha'erwusu Open-pit Mine in Ordos of North China's Inner Mongolia autonomous region.
The electric shovel's underframe beam is carefully placed by two cranes on top of the support structure. [Photo/WeChat account of Nuan news]
The electric shovel is the result of a major joint research effort between Zhunneng Group and Taiyuan Heavy Industry Co. Its lifting and rotating systems are directly powered by permanent magnet motors, making it the world's first WK-55 electric shovel to utilize a permanent magnet direct-drive mechanism, which replaces the conventional AC variable-frequency drive system's lifting and rotating mechanisms with a low-speed, high-torque "permanent magnet motor + roller" direct-drive configuration.
Furthermore, an advanced multi-transmission permanent magnet variable-frequency system is set to supplant the original Siemens 6SE70 electrical control system in the WK-55 electric shovel.
"Using the innovative multi-drive permanent magnet variable-frequency system, along with the toothless lifting mechanism, to replace the traditional AC system in the WK-55 electric shovel has set a benchmark for electric shovel drive technology both domestically and internationally. Meanwhile, the toothless direct-drive mechanism mitigates vibrations produced by the original lifting gearbox, thereby enhancing the reliability of structural components and electrical devices while concurrently reducing failure rates," stated Qiao Shuo, deputy manager of the intelligent construction management center at Zhunneng Group's equipment maintenance center.
The components of the electric shovel are precisely elevated to their designated positions. [Photo/WeChat account of Nuan news]
Adjacent to the massive underframe beam, the components of the electric shovel are systematically organized and precisely elevated to their designated positions, poised for seamless integration with the main body. As per the provided information, assembly and commissioning of the electric shovel is expected to be completed by the end of October.
