Multi-neural electrical busway

• US 5,486,651 A
• Filed: 03/25/1993
• Issued: 01/23/1996
• Est. Priority Date: 03/25/1993
• Status: Expired due to Term

• Current Assignee: Siemens Industry Incorporated (Siemens AG)
• Original Assignee: Siemens Energy & Automation Incorporated (Siemens AG)
• Inventors: Morgan, Robert W.
• Primary Examiner(s): Kincaid, Kristine L.
• Assistant Examiner(s): Ghosh, Paramita
• Application Number:
  US08/037,780
• Time in Patent Office: 1,034 Days
• Field of Search: 174/68.2, 174/88 B, 174/70 B, 174/71 B, 174/72 B, 174/99 B, 174/129 B, 174/133 B, 361/775, 361/624, 439/207, 439/210, 439/212, 439/213, 439/214, 439/114, 439/115, 439/116, 439/119
• US Class Current: 174/68.2
• CPC Class Codes: H02G 5/005 Laminated bus-bars
• CPC Class Codes: H02G 5/007 Butt joining of bus-bars by means of a common bolt, e.g. splice joint electrically conductive connections characterised by contacting members H01R4/58

Abstract

A three-phase electrical power distribution busway having neutral busbars configured to have a higher current carrying capacity than each of the phase busbars of the busway is described, The neutral busbars have a combined cross-sectional area which is greater than the cross-sectional area of each of the phase busbars. The neutral busbars have a rectangular cross-section configured to reduce the skin effect and reduce ohmic heating caused by increased neutral busbar currents resulting from non-linear loads.

Claims

1. A busway system comprising:

a three-phase electrical power source including an A-phase potential, a B-phase potential, a C-phase potential and a neutral potential;

a first conductive phase busbar having a substantially rectangular cross-section of a predetermined width and a first thickness, the first conductive busbar being coupled to the A-phase of the power source;

a second conductive phase busbar having a substantially rectangular cross-section of the predetermined width and the first thickness, the second conductive busbar being coupled to the B-phase of the power source;

a third conductive phase busbar having a substantially rectangular cross-section of the predetermined width and the first thickness, the third conductive busbar being coupled to the C-phase of the power source;

at least two neutral conductive busbars for each quantity of three phase busbars in the busway system, each having a substantially rectangular cross-section of the predetermined width and second and third thicknesses, respectively, the neutral conductive busbars being coupled to the neutral potential, where the sum of the second and third thicknesses is greater than 1.5 times the first thickness; and

a busway housing having first and second ends, where the first, second and third conductive phase busbars and the at least two neutral conductive busbars are supported within the busway and extend between the first and second ends.

2. The system of claim 1, further comprising a ground potential at the power source and a ground busbar having the predetermined width and a fourth thickness, where the ground busbar is supported within the housing, connected to the ground potential and electrically isolated from the housing and the other busbars.

3. The system of claim 1, where all of the busbars include an electrically insulated surface and are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

4. The system of claim 2, where all of the busbars include an electrically insulated surface and are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

5. The system of claim 3, the housing including a first side member, a second side member, a top member and a bottom member, where all of the members are separate until attached together to form the housing, such that the housing has a substantially hollow rectangular cross-section and the busbars are clamped between the top and bottom members.

6. The system of claim 1, where the sum of the second and third thicknesses is at least two times the first thickness.

7. A busway system comprising:

a three-phase electrical power source including an A-phase potential, a B-phase potential, a C-phase potential and a neutral potential;

a first conductive phase busbar having a substantially rectangular cross-section of a predetermined area, the first conductive busbar having a first insulated outer surface and being coupled to the A-phase of the power source;

a second conductive phase busbar having a substantially rectangular cross-section of the predetermined area, the second conductive busbar having a second insulated outer surface and being coupled to the B-phase of the power source;

a third conductive phase busbar having a substantially rectangular cross-section of the predetermined area, the third conductive busbar having a third insulated outer surface and being coupled to the C-phase of the power source;

at least two neutral conductive busbars for each quantity of three phase busbars in the busway system, each having a substantially rectangular cross-section, and fourth and fifth insulated outer surfaces, respectively, the neutral conductive busbars being coupled to the neutral, where the total cross-sectional area of the neutral conductive busbars is greater than 1.5 times the predetermined area; and

a busway housing having first and second ends, where the first, second and third conductive phase busbars and the at least two neutral conductive busbars are located within the busway and extend between the first and second ends.

8. The system of claim 7, further comprising a ground potential at the power source and a ground busbar having a rectangular cross-section, where the ground busbar is supported within the housing, connected to the ground potential, and electrically isolated from the housing and the other busbars.

9. The system of claim 7, where all of the busbars are stacked within the housing such that the busbars are in physical contact with an adjacent busbar.

10. The system of claim 8, where all of the busbars are stacked within the housing such that the busbars are in physical contact with an adjacent busbar.

11. The system of claim 9, the housing including a first side member, a second side member, a top member and a bottom member, where all of the members are separate until attached together to form the housing, such that the housing has a substantially hollow rectangular cross-section and the busbars are clamped between the top and bottom members.

12. The system of claim 7, where the total cross-sectional area of the neutral conductive busbars is at least two times the predetermined area.

13. A busway system comprising:

a three-phase electrical power source including an A-phase potential, a B-phase potential, a C-phase potential and a neutral potential;

a first conductive phase busbar having a substantially rectangular cross-section of a predetermined width and a first thickness, the first conductive busbar having a first insulated outer surface and being coupled to the A-phase of the power source;

a second conductive phase busbar having a substantially rectangular cross-section of the predetermined width and the first thickness, the second conductive busbar having a second insulated outer surface and being coupled to the B-phase of the power source;

a third conductive phase busbar having a substantially rectangular cross-section of the predetermined width and the first thickness, the third conductive busbar having a third insulated outer surface and being coupled to the C-phase of the power source;

at least two neutral conductive busbars for each quantity of three phase busbars in the busway system, each having a substantially rectangular cross-section of the predetermined width and second and third thicknesses, respectively, and fourth and fifth insulated outer surfaces, respectively, the neutral conductive busbars being coupled to the neutral, where the sum of the second and third thicknesses is greater than 1.5 times the first thickness and less than 2.5 times the first thickness; and

a busway housing having first and second ends, where the first, second and third conductive phase busbars and the at least two neutral conductive busbars are located within the busway and extend between the first and second ends.

14. The system of claim 13, further comprising a ground potential at the power source and a ground busbar having the predetermined width and a fourth thickness, where the ground busbar is supported within the housing, connected to the ground potential and electrically isolated from the housing and the other busbars.

15. The system of claim 13, where all of the busbars are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

16. The system of claim 14, where all of the busbars are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

17. The system of claim 15, the housing including a first side member, a second side member, a top member and a bottom member, where all of the members are separate until attached together to form the housing, such that the housing has a substantially hollow rectangular cross-section and the busbars are clamped between the top and bottom members.

18. The system of claim 13, where the sum of the second and third thicknesses is at least two times the first thickness.

19. A busway comprising:

an A-phase busbar having a substantially rectangular cross-section defining a selected electrical conductivity;

a B-phase busbar having a substantially rectangular cross-section defining the selected electrical conductivity;

a C-phase busbar having a substantially rectangular cross-section defining the selected electrical conductivity; and

at least two neutral conductive busbars for each quantity of three phase busbars in the busway, each having a substantially rectangular cross-section defining a total conductivity for the neutral conductive busbars which is greater than 150% of the selected conductivity; and

a busway housing having first and second ends, where the A,phase, B-phase and C-phase busbars and the at least two neutral conductive busbars are located within the busway and extend between the first and second ends.

20. The busway of claim 19, further comprising a ground busbar supported within the housing and electrically isolated from the housing and the other busbars.

21. The system of claim 19, where all of the busbars include an electrically insulated surface, and all of the busbars are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

22. The system of claim 20, where all of the busbars include an electrically insulated surface, and all of the busbars are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

23. The system of claim 21, the housing including a first side member, a second side member, a top member and a bottom member, where all of the members are separate until attached together to form the housing, such that the housing has a substantially hollow rectangular cross-section and the busbars are clamped between the top and bottom members.

24. The system of claim 19, where each phase busbar has a first thickness and the neutral conductive busbars have second and third thicknesses respectively and where the sum of the second and third thicknesses is at least two times the first thickness.

25. A busway system comprising:

an electrical power source including a first phase potential, a second phase potential, and a neutral potential common to both phase potentials;

a first conductive phase busbar having a substantially rectangular cross-section of a first predetermined area and being coupled to the first phase of the power source;

a second conductive phase busbar having a substantially rectangular cross-section of a second predetermined area and being coupled to the second phase of the power source;

at least two neutral conductive busbars for each quantity of two phase busbars in the busway system each having a cross-sectional area and being coupled to the neutral potential of the power source, where the total cross-sectional area of the neutral conductive busbars is at least 0.5 times greater than either one of the first and second predetermined areas; and

a busway housing having first and second ends, where the first and second conductive phase busbars and the at least two neutral conductive busbars are located within the busway and extend between the first and second ends.

26. The system of claim 25, further comprising a ground potential at the power source and a ground busbar, where the ground busbar is supported within the housing, connected to the ground potential, and electrically isolated from the housing and the other busbars.

27. The system of claim 25, where all of the busbars are stacked within the housing such that the busbars are in physical contact with an adjacent busbar.

28. The system of claim 26, where all of the busbars are stacked within the housing such that the busbars are in physical contact with an adjacent busbar.

29. The system of claim 27, the housing including a first side member, a second side member, a top member and a bottom member, where all of the members are separate until attached together to form the housing, such that the housing has a substantially hollow rectangular cross-section and the busbars are clamped between the top and bottom members.

30. A busway comprising:

a first conductive phase busbar having a substantially rectangular cross-section of a predetermined width and a first thickness, the first conductive busbar being configured to carry at least 200 amperes of current at a potential of at least 100 volts;

a second conductive phase busbar having a substantially rectangular cross-section of the predetermined width and the first thickness, the second conductive busbar being configured to carry at least 200 amperes of current at a potential of at least 100 volts;

a third conductive phase busbar having a substantially rectangular cross-section of the predetermined width and the first thickness, the third conductive busbar being configured to carry at least 200 amperes of current at a potential of at least 100 volts;

at least two neutral conductive busbars for each quantity of three phase busbars in the busway, each having a substantially rectangular cross-section of the predetermined width and second and third thicknesses, respectively, where the sum of the second and third thicknesses is at least 0.5 times greater than the first thickness; and

a busway housing having first and second ends, where the first, second and third conductive phase busbars and the at least two neutral conductive busbars are supported within the busway and extend between the first and second ends.

31. The busway of claim 30, further comprising a ground potential at the power source and a ground busbar having the predetermined width and a fourth thickness, where the ground busbar is supported within the housing and electrically isolated from the housing and the other busbars.

32. The busway of claim 30, where all of the busbars include an electrically insulated surface and are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

33. The busway of claim 31, where all of the busbars include an electrically insulated surface and are stacked within the housing such that the busbars are in physical contact with adjacent busbars.

34. The busway of claim 32, the housing including a first side member, a second side member, a top member and a bottom member, where all of the members are separate until attached together to form the housing, such that the housing has a substantially hollow rectangular cross-section and the busbars are clamped between the top and bottom members.

35. The busway of claim 30, where the sum of the second and third thicknesses is at least two times the first thickness.