Can buck boost transformers be used to correct the output of a phase converter which has been used to create a three phase output from a single phase source? The created phase(s) has significantly higher voltages than the utility pass through phase.

Issue:
Mismatch of phase converter output with load voltage needs

Product Line:
LV Transformers

Environment:
Applies to Buck Boost Transformers by SquareD/Schneider Electric

Cause:
Phase converters may produce a voltage output that must be changed up or down by use of a Low Voltage Transformer

Resolution:

This is a classic issue with phase converters. Phase converters, other wise known as motor-generators, experience high regulation (voltage drop) between no load and full load on the generated phase(s) while the utility pass through phase remains much more stable. To prevent having too low a voltage at full load, the typical phase converter compensates for the regulation by providing a significantly higher voltage at no load. Historically this was not as important an issue when phase converters were used to run three phase motors. With the advent of computer controlled ``intelligent`` equipment, the phase converter may be less desirable. Only the manufacturer of the load equipment can answer that question. SquareD/Schneider Electric does not recommend the use of buck boost Transformers with phase converters because the correction application is often complex, involving multiple buck boost Transformers, as well as not being constant due to the regulation through the phase converter. Any guidance in the application of buck boost Transformers with a particular phase converter for a piece of equipment must come from the collaboration of the phase converter manufacturer and the load equipment manufacturer.

Released for: Schneider Electric USA