Advanced Variable Speed Drive

The U.S. Navy has independent variable speed drive (VSD) projects geared for specific system applications. However, there is no long term or fleet wide effort to develop a standard 450VAC VSD system design which will meet the stringent requirements set forth in MIL-STD 1399 (Electrical Power System Interface Standards) and MIL-STD 461E (Electromagnetic Interference Standards). The current 450VAC VSD technologies employed by these various projects require the use of large and heavy input transformers to reduce the harmonic noise generated by the VSD or large input EMI filters to mitigate high frequency (EMI) noise emissions. In most cases it is the input transformer requirement, which prohibits the use of the VSD, due to shipboard space and weight restrictions. The Advanced Variable Speed Drive (AVSD) project will develop an advanced AC inverter system for use on 450 Volt applications to eliminate input harmonics and reduce EMI noise generation to within the limitations of Mil-Std- 461. Furthermore, the advancements in shipboard automation and control of motor-based systems by variable speed drives will be drastically improved by the integration of the AVSD PLC controls, which can be used to enable Condition Based Maintenance software applications such as ICAS, and otherwise contribute to reducing motor systems' maintenance requirements. The use of variable speed drives will allow total integration of motor-based systems into the automated ship controls environment.