Variable transformer, reactor and method of their control

• US 4,837,497 A
• Filed: 12/29/1987
• Issued: 06/06/1989
• Est. Priority Date: 12/29/1987
• Status: Expired due to Fees

• Current Assignee: Gregory Leibovich
• Original Assignee: Gregory Leibovich
• Inventors: Leibovich, Gregory
• Primary Examiner(s): Beha, Jr., William H.
• Application Number:
  US07/128,958
• Time in Patent Office: 525 Days
• Field of Search: 323/247, 323/328, 323/254, 323/331, 323/334, 323/339, 323/345, 336/10, 336/12, 336/143, 336/147, 336/155, 336/184
• US Class Current: 323/345
• CPC Class Codes: G05F 3/04 wherein the variable is ac
• CPC Class Codes: H01F 2029/143 with control winding for generating magnetic bias
• CPC Class Codes: H01F 29/02 with tappings on coil or winding; with provision for rearrangement or interconnection of windings
• CPC Class Codes: H01F 30/10 Single-phase transformers H01F30/16 takes precedence
• CPC Class Codes: H01F 30/12 Two-phase, three-phase or polyphase transformers

Abstract

A variable transformer, reactor having a core combining at least two complete core elements wiht a common yoke; primary winding divided into two independently fed sets of phase coils wound in opposite direction, arranged on symmetrical legs of core elements and separated by the common yoke; secondary winding with each phase coil divided into two wound in opposite direction portions carried by symmetrical core legs, adjacent to the primary coils and separated by common yoke. The secondary short-circuited reactor winding is reduced to at least one close loop member with loop portions separated by the common yoke. The single, polyphase apparatus has at least one primary coil per set that includes a controllable device in circuit relation therewith to enable control of one primary coil relative to the other, either in current magntidue or in current phase shift. The controllable device being either a silicon control rectifier, triac or transistor. By continuous control of the controllable device an apparatus variable output parameters are obtained.

Claims

1. In a transformer, the combination comprising:

core means combining at least two complete core elements with at least one core yoke common for both said core elements;

primary winding means including at least two phase sets of independently fed coils with each phase set having at least one coil wound in the direction opposite to the associated coil of other set, carried by symmetrical core legs of each said core elements and separated by said common yoke;

secondary winding means including at least one phase set having at least one coil with at least two coil portions wound in opposite direction, carried by said symmetrical core legs of each said core elements and separated by said common yoke;

means for applying power to said primary winding phase sets including means for selectively controlling the application of power to at least one said phase set relatively to the other for enabling control of one of the currents therein and phase shift of the currents therein relative to the other said phase set to control operating parameters of said transformer.

2. The combination according to claim 1 wherein said transformer is a three phase transformer having:

core means formed of at least two complete, at least three legs, cores having common yoke;

at least two sets of three phase primary coils associated in oppositely disposed pairs;

at least one secondary three phase winding with each phase coil having at least two oppositely disposed portions;

wherein said means for selectively controlling the application of power include control device means in circuit relation with at least one of said set of primary phase coils.

3. The combination according to claim 1 wherein said transformer is a single phase transformer having:

at least two primary oppositely disposed coils;

at least one secondary coil having at least two oppositely disposed portions separated by said common core yoke;

wherein said means for selectively controlling the application of power include control device means in circuit relation with at least one of said primary coils.

4. The combination according to claim 1 wherein said means for selectively controlling the application of power includes control device means in circuit relation with at least one of phase coils.

5. The combination according to claim 4 wherein said control device means includes at least one silicon controlled rectifier.

6. The combination according to claim 4 wherein said control device means includes at least one triac.

7. The combination according to claim 2 wherein said means for selectively controlling the application of power include controllable semiconductor device means in circuit relation with at least one of said primary phase coils set.

8. The combination according to claim 3 wherein said means for selectively controlling the application of power includes controllable semiconductor device means in circuit relation with at least one of primary coils.

9. The combination according to claim 2 wherein said control device means includes at least one silicon controlled rectifier.

11. The combination according to claim 3 wherein said control device means includes at least one of a triac and a silicon contolled rectifier.

12. The combination according to claim 1 wherein each phase coil of associated in pairs said primary phase coils sets is an arrangement of two legs coil having at least one tap.

13. The combination according to claim 12 wherein said means for selectively controlling the application of power include control device means in circuit relation with each leg of each said two legs coil.

14. The combination according to claim 13 wherein said control device means includes silicon controlled rectifiers.

15. The combination according to claim 13 wherein said control device means include controllable semiconductor device means.

10. The combination according to claim3 wherein said control device means includes at least one silicon controlled rectifier.

16. In a transformer, the combination comprising:

core means formed of at least two complete core elements with at least one, common for both said core elements, core yoke for carrying at least two independently established magnetic fluxes;

primary winding means including at least two phase sets of independently fed, oppositely disposed, carried by symmetrical core legs, and separated by said common yoke coils for independently establishing at least two magnetic fluxes;

secondary winding means including at least one phase set having at least one coil with at least two oppositely disposed portions, carried by said symmetrical core legs, and separated by said common yoke, wherein said coil compounds elecromotive forces induced in said coil portions linked by said fluxes;

means for applying power to said primary winding phase sets including

(a) means for applying power to said at least one phase coil of one of said phase sets and

(b) means for controlling the application of power to the other said, at least one, phase coil of the other said phase set for enabling control of at least one of

(i) the current therein relative to the other said at least one phase coil and

(ii) the phase shift of the current therein relative to the other said, at least one, phase coil for controlling the operating parameters of said transformer.

17. The combination of claim 16 wherein said transformer is a three phase transformer having:

a core formed of at least two complete, at least three legs, cores with common yoke;

at least two sets of three phase primary coils associated in oppositely disposed pairs;

at least one set of three phase secondary coils with each coil having at least two oppositely disposed portions installed adjacent to associated said primary phase coils;

wherein said means for selectively controlling the application of power include controllable semiconductor device means in circuit relation with at least one of said primary phase coils set.

18. The combination of claim 16 wherein said transformer is a single phase transformer having:

a core formed of at least two complete core elements with common yoke;

at least two primary oppositely disposed coils;

at least one secondary coil having at least two oppositely disposed portions installed adjacent to associated said primary coils;

wherein said means for selectively controlling the application of power include controllable semiconductor device means in circuit relation with at least one of said primary coils.

19. The combination according to claim 16 wherein each phase coil of associated in pairs primary phase coils sets includes at least two identically wound, connected in series, accessible common point coils forming two legs center tap coil arrangement.

20. A method for controlling the output parameters of a transformer comprising the steps of:

(a) independently establishing at least two magnetic fluxes in said transformer core carring at least two primary phase coils;

(b) linking said fluxes by at least one secondary phase coil having at least two portions;

(c) compounding by said secondary coil electromotive forces induced in said coil portions, linked by said fluxes;

(d) varying a sum of said electromotive forces by shifting a relative phase and a magnitude of said fluxes, and currents producing said fluxes;

(e) controlling said relative phase and magnitude of said currents by varying firing angle of controllable semiconductor devices installed in circuit relation with at least one of said primary phase coils.

21. In a reactor, the combination comprising:

core means formed of at least two complete core elements with at least one, common for both said core elements, core yoke for carrying at least two independently established magnetic fluxes;

primary winding means including at least two phase sets of independently fed, oppositely disposed, carried by symmetrical core legs, separated by said common yoke coils for independently establishing at least two magnetic fluxes;

secondary winding means including at least one phase set having at least one short-circuited coil with at least two oppositely disposed portions, carried by said symmetrical core legs, and separated by said common yoke, wherein said coil compounds elecromotive forces induced in said coil portions linked by said fluxes;

means for applying power to said primary winding phase sets including

(a) means for applying power to said at least one phase coil of one of said phase sets and

(b) means for controlling the application of power to the other said, at least one, phase coil of the other said phase set for enabling control of at least one of

(i) the current therein relative to the other said at least one phase coil and

(ii) the phase shift of the current therein relative to the other said, at least one, phase coil for controlling the operating parameters of said reactor.

22. The combination of claim 21 wherein said reactor is a three phase reactor having:

a core formed of at least two complete, at least three legs, cores with common yoke;

at least two sets of three phase primary coils associated in oppositely disposed pairs;

at least one set of three phase secondary short-circuited coils with each coil having at least two oppositely disposed portions installed adjacent to associated said primary phase coils;

wherein said means for selectively controlling the application of power include controllable semiconductor device means in circuit relation with at least one of said primary phase coils set.

23. The combination according to claim 22 wherein said each short-cicuited phase coil of said secondary winding means is a single turn coil.

24. The combination of claim 21 wherein said reactor is a single phase reactor having:

a core formed of at least two complete core elements with common yoke;

at least two primary oppositely disposed coils;

at least one secondary short-circuited coil having at least two oppositely disposed portions installed adjacent to associated said primary coils;

wherein said means for selectively controlling the application of power include controllable semiconductor device means in circuit relation with at least one of said primary coils.

25. The combination according to claim 24 wherein said secondary short-circuited coil is a single turn coil.

26. A method for controlling the impedance of a reactor comprising the steps of:

(a) independently establishing at least two magnetic fluxes in said reactor core carring at least two primary phase coils;

(b) linking said fluxes by at least one secondary short-circuited phase coil having at least two portions;

(c) compounding by said secondary coil electromotive forces induced in said coil portions, linked by said fluxes;

(d) varying a sum of said electromotive forces by shifting a relative phase and a magnitude of said fluxes, and currents producing said fluxes;

(e) controlling said relative phase and magnitude of said currents by varying firing angle of controllable semiconductor devices installed in circuit relation with at least one of said primary phase coils.

27. In a reactor, the combination comprising:

core means combining at least two complete core elements with at least one core yoke common for both said core elements;

primary winding means including at least two phase sets of independently fed coils with each phase set having at least one coil wound in direction opposite to the coil of other set and carried by symmetrical core legs separated by said common yoke;

secondary winding means including at least one phase short-circuited coil having at least two coil portions wound in opposite direction, carried by symmetrical core legs of each core element and separated by said common yoke;

means for applying power to said primary winding phase sets including means for selectively controlling the application of power to at least one said set relatively to the other for enabling control of one of the current therein and phase shift of the current therein relative to the other said phase set to control operating parameters of said reactor.

28. The combination according to claim 27 wherein said reactor is a three phase reactor having:

at least two sets of three phase primary coils associated in pairs;

at least one three phase secondary winding with each short-circuited phase coil having two portions;

means for selectively contolling the application of power including control device means in circuit relation with at least one of said sets.

29. The combination according to claim 27 wherein said reactor is a single phase reactor having;

at least two primary windings associated in pairs;

at least one short-circuited secondary winding with two portions;

wherein said means for selectively controlling the application of power includes control device means in circuit relation with at least one of said primary windings.

30. The combination according to claim 28 wherein said secondary winding means includes at least three phase short circuited loop members having open loop portions carried by symmetrical core legs of each said core elements and separated by said common yoke.

31. The combination according to claim 29 wherein said secondary winding means includes at least one short-circuited loop member having open loop portions carried by symmetrical core legs of each said core elements and separeted by said common yoke.

32. The combination according to claim 27 wherein said means for selectively controlling the application of power includes control device means in circuit relation with at least one of phase coils.

33. The combination according to claim 32 wherein control device means includes at least one silicon controlled rectifier.

34. The combination according to claim 32 wherein said control devive means includes at least one triac.

36. The combination according to claim 28 wherein said means for selectively controlling the application of power includes controllable device means in circuit relation with at least one of primary coils.

37. The combination according to claim 28 wherein said control device means includes at least one of a triac and a silicon controlled rectifier.

35. The combination according to claim27 wherein said means for selectively controlling the application of power includes controllable semiconductor device means.