Medium or high voltage switch having spherical-bearing-type mechanical connection
A medium or high voltage switch including a moveable contact element and a stationary contact element is described. Therein, a moveable-contact guiding portion of the moveable contact element and a stationary-contact guiding portion of the stationary contact element are shaped for establishing a spherical-bearing-type mechanical connection between each other, thereby aligning a center of the moveable-contact guiding portion with a center of the stationary-contact guiding portion while allowing an angular flexion between the moveable and stationary contact elements. Furthermore, at least one of the stationary-contact guiding portion and the moveable-contact guiding portion is electrically insulating.
1. A medium or high voltage switch comprising:
a moveable contact element being moveable along an axis for opening and closing the medium or high voltage switch, the moveable contact element comprising
a moveable-contact contacting portion, and
a moveable-contact guiding portion,
a stationary contact element comprising
a stationary-contact contacting portion configured to make an electrical connection with the moveable-contact contacting portion when the medium or high voltage switch is closed, and
a stationary-contact guiding portion, the stationary-contact guiding portion being configured to engage with the moveable-contact guiding portion when the medium or high voltage switch is closed, wherein
at least one of the stationary-contact guiding portion and the moveable-contact guiding portion is electrically insulating, and wherein
the moveable-contact guiding portion and the stationary-contact guiding portion are shaped for establishing, when the moveable-contact guiding portion and stationary-contact guiding portions are engaged with each other, a spherical-bearing mechanical connection between the moveable-contact guiding portion with the stationary-contact guiding portion, thereby aligning a center of the moveable-contact guiding portion with a center of the stationary-contact guiding portion while allowing an angular flexion between the moveable contact element and the stationary contact element.
2. The medium or high voltage switch according to claim 1 , wherein the stationary contact element is a fixed contact element arranged such that when the medium or high voltage switch is opened, the moveable contact element is moved away from the fixed contact element whereby an axial dielectric gap is created between the fixed contact element and the moveable contact element.
3. The medium or high voltage switch according to claim 2 , wherein at least one of the stationary-contact guiding portion and the moveable-contact guiding portion has a tapered surface portion for receiving the other one of the stationary-contact guiding portion and the moveable-contact guiding portion even under axial misalignment of their centers, and for guiding the stationary-contact guiding portion and the moveable-contact guiding portion into axial alignment of their centers while the moveable contact element is moved along the axis for closing the medium or high voltage switch.
4. The medium or high voltage switch according to claim 1 , wherein the stationary contact element is a slider contact element.
5. The medium or high voltage switch according to claim 1 , wherein the stationary contact element is a first stationary contact element, the moveable-contact contacting portion is a first moveable-contact contacting portion, the moveable-contact guiding portion is a first moveable-contact guiding portion, the stationary-contact contacting portion is a first stationary-contact contacting portion, and the stationary-contact guiding portion is a first stationary-contact guiding portion, wherein
the moveable contact element further has a second moveable-contact contacting portion, and a second moveable-contact guiding portion, and wherein
the medium or high voltage switch further comprises a second stationary contact element, the second stationary contact element having:
a second stationary-contact contacting portion configured to make an electrical connection with the second moveable-contact contacting portion when the medium or high voltage switch is closed, and
a second stationary-contact guiding portion configured to engage with the second moveable-contact guiding portion when the medium or high voltage switch is closed, wherein
the second moveable-contact guiding portion and the second stationary-contact guiding portion are shaped for establishing, when the second moveable-contact guiding portion and the second stationary-contact guiding portion are engaged with each other, a second spherical-bearing mechanical connection aligning a center of the second moveable-contact guiding portion with a center of the second stationary-contact guiding portion while allowing a flexion between the moveable contact element and the second stationary contact element.
6. The medium or high voltage switch according to claim 1 , wherein the spherical-bearing mechanical connection allows a flexion about an angle in any direction off the axis.
7. The medium or high voltage switch according to claim 1 , wherein the spherical-bearing mechanical connection allows a flexion about an angle of at least 0.5°.
8. The medium or high voltage switch according to claim 1 , wherein the stationary-contact contacting portion is mounted on an elastic element biasing the stationary-contact contacting portion towards the moveable-contact contacting portion.
9. The medium or high voltage switch according to claim 1 , wherein the stationary-contact contacting portion, the moveable-contact contacting portion, the stationary-contact guiding portion and the moveable-contact guiding portion each have an axial distance of less than 6 mm.
10. The medium or high voltage switch according to claim 1 , wherein at least one of the moveable-contact guiding portion and the stationary-contact guiding portion has a protruding surface portion protruding towards the other one of the moveable-contact guiding portion and the stationary-contact guiding portion for establishing, when the moveable-contact guiding portion and the stationary-contact guiding portion are engaged with each other, the mechanical spherical-bearing connection between the moveable-contact guiding portion with the stationary-contact guiding portion.
11. The medium or high voltage switch according to claim 10 , wherein the protruding surface portion is convex.
12. The medium or high voltage switch according to claim 1 , wherein the moveable-contact guiding portion is arranged radially surrounding the stationary-contact guiding portion and/or wherein the stationary-contact contacting portion is arranged radially surrounding the moveable-contact contacting portion.
13. The medium or high voltage switch according to claim 5 , wherein the first stationary contact element and the second stationary contact element are essentially axially symmetric about the axis.
14. The medium or high voltage switch according to claim 1 , wherein the medium or high voltage switch comprises a starting-switch disconnector or an earthing switch.
15. A medium or high voltage circuit breaker having at least one of a starting-switch disconnector and an earthing switch according to claim 14 .
16. The medium or high voltage circuit breaker of claim 15 , wherein the medium or high voltage circuit breaker is a generator circuit breaker.
17. The medium or high voltage switch according to claim 5 , wherein the second stationary contact element is a slider contact element.
18. The medium or high voltage switch according to claim 9 , wherein the stationary-contact guiding portion and the moveable-contact guiding portion are arranged to overlap with a single common plane perpendicular to the axis.
19. The medium or high voltage switch according to claim 3 , wherein the stationary contact element is a slider contact element.
20. The medium or high voltage switch according to claim 11 , wherein the protruding surface portion is shaped as a segment of a sphere or shaped as a segment of a convex polygon.