Converter for single-phase and three-phase operation, D.C. voltage supply and battery charger
A Converter ( 1 a .1 c ) for single-phase and three-phase Operation which comprises a three-phase rectifier to which three coils (L a , L b , L c ) are connected on the mains side is described. A first coil (L a ) is provided on the mains side with a switch (S) which connects the first coil (L a ) to the mains during three-phase Operation and connects it via a capacitor (C) either to the lower end (FP) of the rectifier or on the mains side to another coil (L b , L c ) during single-phase Operation. In addition, a d.c. voltage supply and a battery charger ( 5 a .5 c ) which comprise the Converter ( 1 a .1 c ) according to the invention are described.
1. A converter system for single-phase and three-phase operation comprising:
a converter;
a first mains branch for said converter;
said first mains branch connected at a point between a first set of two rectifying diodes in series;
a first choke coil in said first mains branch, said first choke coil located before said connection point to between said first set of two rectifying diodes;
a second mains branch for said converter;
said second mains branch connected at a second point between a second set of two rectifying diodes in series;
a second choke coil in said second mains branch, said second choke coil located before said connection second point to between said second set of two rectifying diodes;
a third mains branch for said converter;
a switch;
a third choke coil connected to said switch and to a third connection point between a third set of two rectifying diodes;
said switch having a first position that connects said third choke coil to said third mains branch for three-phase current conversion; and,
said switch having for single-phase current conversion a second position that connects said third choke coil to a capacitor, said capacitor also connected to a low end of said converter system.
2. A converter system as claimed in claim 1 , further comprising:
a respective switch connected antiparallel to each one of said rectifying diodes.
3. A converter system as claimed in claim 1 , further comprising:
a two-pole inverter connected to said low end of said converter and to a high end of said converter;
a transformer primary side connected to said inverter; and,
a transformer secondary side, said transformer secondary side connected to a two-pole rectifier configured for load connection.
4. A converter system for single-phase and three-phase operation comprising:
a converter;
a first mains branch for said converter;
said first mains branch connected at a point between a first set of two rectifying diodes in series;
a first choke coil in said first mains branch, said first choke coil located before said connection point to between said first set of two rectifying diodes;
a second mains branch for said converter;
said second mains branch connected at a second point between a second set of two rectifying diodes in series;
a second choke coil in said second mains branch, said second choke coil located before said connection second point to between said second set of two rectifying diodes;
a third mains branch for said converter;
a switch;
a third choke coil connected to said switch and to a third connection point between a third set of two rectifying diodes;
said switch having a first position that connects said third choke coil to said third mains branch for three-phase current conversion; and,
said switch having for single-phase current conversion a second position that connects said third choke coil to a capacitor, said capacitor also connected to said second mains branch.
5. A converter system as claimed in claim 4 , further comprising:
a respective switch connected antiparallel to each one of said rectifying diodes.
6. A converter system as claimed in claim 4 , further comprising:
a two-pole inverter connected to said low end of said converter and to a high end of said converter;
a transformer primary side connected to said inverter; and,
a transformer secondary side, said transformer secondary side connected to a two-pole rectifier configured for load connection.
7. A converter system for single-phase and three-phase operation comprising:
a converter;
a first mains branch for said converter;
said first mains branch connected at a point between a first set of two rectifying diodes in series;
a first choke coil in said first mains branch, said first choke coil located before said connection point to between said first set of two rectifying diodes;
a second mains branch for said converter;
said second mains branch connected at a second point between a second set of two rectifying diodes in series;
a second choke coil in said second mains branch, said second choke coil located before said connection second point to between said second set of two rectifying diodes;
a third mains branch for said converter;
two part-coils for said third mains branch;
a switch for said two part-coils of said third mains branch, said switch having a first position connecting said part-coils in parallel sense to said third mains branch for three-phase conversion operation, said first position also connecting said part-coils in parallel to a third point between a third set of two rectifying diodes in series; and,
said switch having for single-phase operation a second position disconnecting said two part-coils from said third mains branch and connecting said two part-coils in series between said third point located between said third set of diodes and a capacitor connected to a low end of said converter.
8. A converter system as claimed in claim 7 , further comprising:
a respective switch connected antiparallel to each one of said rectifying diodes.
9. The converter system as claimed in claim 7 wherein:
said two part-coils are coupled in the same sense with said first and second choke coils during three-phase operation, and during single-phase operation one of said part-coils is coupled in the same sense as said first and second choke coils while the second of said part-coils is coupled in the opposite sense to said first and second choke coils.
10. The converter system as claimed in claim 7 wherein:
said two part-coils each have the same number of turns as said first and second choke coils.
11. A converter system as claimed in claim 7 , further comprising:
a first two-pole inverter connected to said converter;
a primary side of a first transformer connected to said first two-pole inverter;
a first two-pole rectifier, said first two-pole rectifier connected to a secondary side of said first transformer;
a second two-pole inverter connected to said converter;
a primary side of a second transformer connected to said second two-pole inverter; and,
a second two-pole rectifier, said second two-pole rectifier connected to a secondary side of said second transformer.
12. A converter system as claimed in claim 11 , further comprising:
a first inverter capacitor connected in parallel to said first two-pole inverter; and,
a second inverter capacitor connected in parallel to said second two-pole inverter.
13. A converter system as claimed in claim 11 , further comprising:
a first rectifier capacitor connected in parallel to said first two-pole rectifier; and,
a second rectifier capacitor connected in parallel to said second two-pole rectifier.
14. The converter system as claimed in claim 11 wherein:
said first and second two-pole inverters are connected in parallel to said converter.
15. The converter system as claimed in claim 11 wherein:
said first and second two-pole inverters are connected in series to said converter.
16. The converter system as claimed in claim 11 wherein:
said rectifiers are connected in series.
17. The converter system as claimed in claim 11 wherein:
said rectifiers are connected in parallel.
18. A converter system as claimed in claim 11 , further comprising:
a plurality of switches in said first and second inverters; and,
antiparallel-connected rectifying diodes, respectively, for each one of said plurality of switches.
19. A converter system as claimed in claim 11 , further comprising:
a plurality of rectifier-incorporated rectifying diodes in said first and second rectifiers; and,
antiparallel-connected switches, respectively, for each one of said rectifier-incorporated rectifying diodes.
20. A converter system as claimed in claim 7 , further comprising:
a first capacitor connected in parallel to said first set of two rectifying diodes;
a second capacitor connected in parallel to said second set of two rectifying diodes; and,
a third capacitor connected in parallel to said third set of two rectifying diodes.