With the Flender EMPP vertical-mill drive, this firm has developed a drive concept that prevents load surges arising from short power supply interruptions and optimizes the transfer of forces between the drive unit and the mill. The number of components that may be susceptible has been reduced, which increases the plant availability and enables the power range to be expanded to 15 MW. The EMPP features an integral, permanent magnet synchronous motor supplied by a frequency converter. The omission of the bevel gear stage and the coupling enables the high forces to be optimally transferred. The grinding plate can be precisely controlled via the closed-loop speed control of the frequency converter. Typical applications of vertical mills include crushing of raw materials and cement in the building materials industry, and for coal preparation. — Siemens Industry Sector, Erlangen, Germany