Siemens successfully concludes pilot operation of a medium-voltage converter

摘要

For the first time, a Simovert MV medium-voltage converter has been used for supplying asynchronous machines at the Moldavia Metal Plant (MMZ) in Rybnitsa, Moldova. The Siemens Industrial Solutions and Services Group (I&S) is there fore now able to provide this technology for applications in rolling mills. The new drive concept offers improved dynamic response while at the same time reducing capital outlay operating costs.Asynchronous drives have a number of advantages over with a current-source DC-link converter and synchronous machine. Dispensing with the current-source DC-link converter enables the motor speed to be adapted more quickly to changing requirements in the production process. At the same time the system features reduced reactive-power demand and fewer phase effects on the system. As a result it is possible to use transformers and medium-voltage switchgear with a lower design rating, and in that way save on capital outlay. The comparatively low maintenance needs of asynchronous motors help to reduce running costs.