I am looking for all parameters of distribution transformers, such as winding resistance, reactance, and impedance, neutral resistance , and symmetrical impedance for delta star type.
I cannot complete the calculation without this important information, please help me
The reference you probably want is the book "TRANSFORMER CONNECTIONS" by General Electric. I have two editions: GET-2B (1941) and GET-2G (1951). These are still available, as determined by a quick google search "ge transformer connections book".
As I recall, an important thing you need to watch out for is using 3 single phase transformers for 3-wire, 3 phase ac-ac. With a star-star (also know as Y-Y) connection the floating neutral tends to fly around at 3 times the line frequency due to 3rd harmonics in the magnetizing current. In extreme cases, this can cause the floating neutral voltage to go outside the phasor diagram of the input voltage.
The risk of a delta-delta connection is large circulating currents due to mismatches in the transformers. Some of these problems may also show up in single core or shell type transformers, but Y-delta or delta-Y connections are generally a safe option. (Three phase transformers open up a whole new area of complexity over single phase.)
At over 130 pages, the book is very informative on many unanticipated aspects, including 2 phase systems (and conversion between 2 and 3 phases), generation of more than 3 phases, and using zig-zag transformers to create a hard 4th wire neutral when none exists.
A related book which may be of interest is "Rectifier Circuits: Theory and Design" by Johannes Schaefer, John Wiley & Sons, 1965, Library of Congress 65-12703. At over 300 pages it contains a wealth of information on the legacy technology of single and poly-phase ac rectifier circuits.
These parameters can be obtained for a transformer by conducting various tests like winding resistance measurement, no load test, short circuit test etc. Neutral resistance depends on the field condition and need to be measured in field (Assuming it is an earthed system). Calculation is possible if you have the values of no load loss, full load loss, %ge impedance etc. On transformer testing there are plenty of books available.
These parameters can be measured directly by impedance analyzer or vector network analyzer.
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