DC to DC Conversion
Source: UFTO Bulletin #22
Date: 5/1/96    Record No.: 10354
Contact: Robert Eccles, President, DC Transformations, Beverly MA, 508-921-5505

DC to DC Conversion
A Boston-based startup company, DC Transformations, has developed and patented a new class of low cost and high performance DC conversion devices. Without transformers, they can do harmonic-free inversion, rectification and DC to DC step-up/down, using standard available components -- thyristers (not the more sophisticated devices like GTO's now coming onto the market). The systems can regulate and protect (fault interrupt in 0.3 msec.), are self-commutating, and are easy to understand, build and scale.

The range of applications is extensive. Test data already exist for:
- DC/DC step up 1 kV to 6 kV at 100 kW
- DC/DC step down 12 kV to 2 kV at 100kW
- Harmonic-free (<1%) rectification at 140 kW, with power factor control

Tests are in progress for:
- DC to AC at 440 V and 140 kW (for the DARPA Hybrid vehicle program)
This can supply variable speed drives at any voltage and frequency
- Static VAR generator, 440 V, 500kVAR, lead and lag (1 MVAR swing).

For the first time, it may be feasible (cost-effective!) to use DC in the distribution system, with converters at each end of a feeder (or to supply DC loads directly?). This could more than double the capacity of a feeder. (storage, batteries, T&D, transmission, ASD)

Keywords: power electronics