Single phase converters 4

[csteele]

Has anyone ever found any information about how a single phase converter works. I am looking for the technical info behind it. If there is a website or book that someone knows of that would be great

thanks
chris

 

[charlierod]

You can consult for example
Power Electronics : Circuits, Devices and Applications (3rd Edition) by Muhammad H. Rashid

 

[alehman]

There are two basic types, static and rotary. A quick Google turned up these -

http://www.phaseconverter.com/

http://www.majorpower.com/phase/

http://www.polyphaz.com/

 

[busbar]

On the North American continent, “phase converters” seem to have a cottage-industry foundation. There are an assortment products that are marketed for various semi-niche ‘mom & pop’ applications, like very rural broadcast transmitters, CNC mills and laser interferometers.

Their viability seems to be indirectly based on various electric utilities’ line-extension rules and fees.

Mindful that they are a hawking their wares, you can find bits and pieces at sites like:

http://www.gwm4-3phase.com/uands_index.htm

http://home.earthlink.net/~ojmsmith/indexd.html

http://www.capacitorconvertors.com/staticinstructions.pdf

[There are also FAQ-like articles linked in usenet metalworking and woodworking newsgroups.]

Many smaller VFDs have the capability of 1ø input, 3ø output that function as phase converters with additional control functions [and limitations.]

See also thread237-91110 Note that recent NEC editions have a dedicated article—455.

 

[jbartos]

Comment on the original posting: There are various single phase converters, namely:
1. Single phase to three phase. These are essentially AC-DC-AC converters similar to 3phase AC-DC-AC converters except the AC-DC conversion (rectification) is single phase instead of three phase. The hardware for single phase to dc conversion is simpler than three-phase to dc conversion (rectification).
2. Another type of single phase converters are single phase converters, AC-DC-AC for single phase loads, e.g. single phase motor variable speed drives.
3. Another single phase converter AC-DC-AC is a frequency converter, e.g. 50Hz to 60Hz, 60Hz to 400Hz, etc.

To narrow down the topic, it would be nice if the original posting was elaborated on to become more specific.

 

[csteele]

To reply to Jbartos, The information that I am looking for is the theory behind a single phase to 3-phase converter. Namely a static converter that converts the single phase power to run a 3-phase piece of equipment. Looking and searching on the internet, I have seen some schematics where they use a capacitor between one of the hot legs and the neutral (70-100uf/hp) and using this setup are able to make 3-phase power. I am trying to find out the theoretical explanation behind this. Any information as to books or sites would be very helpful.

thanks

 

[jbartos]

Comment: The capacitors can displace voltage at one terminal such that the three phase resembling power supply can be formed. However, there are some limitation on the motor loading. Visit

http://www.phase-a-matic.com/StaticDescription.htm

etc. If this is acceptable, the further engineering and design may be pursued.
Reference:
M.G. Say "Alternating Current Machines," John Wiley & Sons, 1978
Single to three phase conversion.
Also, there are some postings in this Forum on this topic. E.g. search for:
Running a 3-phase induction motor on single phase