Reliability, Interfacing and Standardization Aspects in High Power AC Drive Applications

Selecting, buying and installing an electric variable speed drive system (EVSDS) for a high power drive application is an activity with project character. It is not a product business. In order to bring the audience to the same level of understanding, there is a chapter with an overview of different VSDS technologies. This overview also gives our opinion of what a large AC drive should be capable of. In the main part of the paper we will review the project handling process. The stages of this process cover project planning, all phases of the drive order, operation, maintenance, servicing and upgrading if needed, up to dismantlement. Focus is set on those issues that have the greatest impact on the reliability of the drive. Besides state-of-the-art technology, two important preconditions are required for a successful application of variable speed drive systems. These are proper drive integration into the drive environment and standardization based on modular structures. By means of a case history we will report on a large AC drive project and the experience gained in this context. This paper is in particular addressed to application engineers and persons who are involved in selection and operation of large VSDSs (from a few megawatt to hundreds of megawatt).