Permanent magnet contactor
A power system is disclosed. The system may include an electrical contactor including a pair of plates arranged to scissor between open and closed positions. The plates may have magnets embedded therein such that in the closed position, a subset of the magnets having opposite polarity are aligned to encourage touching of electrical contacts of the plates, and in the open position, a subset of the magnets having same polarity are aligned to encourage separation of the electrical contacts.
1. A power system comprising:
an electrical contactor including a pair of plates arranged to scissor between open and closed positions, the plates having magnets embedded therein such that
in the closed position, a subset of the magnets having opposite polarity are aligned to encourage touching of electrical contacts of the plates, and
in the open position, a subset of the magnets having same polarity are aligned to encourage separation of the electrical contacts.
2. The power system of claim 1 , wherein the pair includes a fixed plate and a rotating plate, and wherein when in the closed position, at least a portion of the rotating plate overlaps and touches at least a portion of the fixed plate, and when in the open position, the rotating plate is spaced away from the fixed plate.
3. The power system of claim 2 , wherein the electrical contactor further includes a spring connected to the rotating plate, and configured to bias the rotating plate to either the open position or the closed position.
4. The power system of claim 2 wherein the electrical contactor further includes an electromechanical actuator connected to the rotating plate, and configured to move the rotating plate from either the closed position to the open position and vice-versa.
5. The power system of claim 2 wherein the electrical contactor further includes a high-voltage terminal electrically connected to the fixed plate, and configured to electrically connect a battery to the electrical contactor.
6. The power system of claim 2 wherein the electrical contactor further includes a travel limit member extending from the fixed plate through an elongated slot defined by the rotating plate, and configured to stop the rotating plate as the rotating plate is moved from the open position to the closed position and vice-versa.
7. The power system of claim 2 wherein the electrical contactor further includes a bushing including a head attached to a shaft defining an axis, and pivotally connecting the rotating plate to the fixed plate, wherein the head acts as a stop as the rotating plate moves along the axis defined by the bushing.
8. An electrical contactor comprising:
a pair of plates arranged to scissor between open and closed positions, the plates having magnets and electrical contacts embedded therein such that
responsive to a subset of the magnets of same polarity being brought into alignment, the plates repel to separate the electrical contacts, and
responsive to a subset of the magnets of opposite polarity being brought into alignment, the plates attract to connect the electrical contacts.
9. The electrical contactor of claim 8 , wherein the pair includes a fixed plate and a rotating plate, and wherein when the rotating plate moves between the open and closed positions, the rotating plate moves along a curved trajectory relative to the fixed plate.
10. The electrical contactor of claim 9 , wherein the magnets include first, second, and third magnets, and wherein the first magnet is disposed within the rotating plate and the second and third magnets are disposed within the fixed plate and have opposite polarity.
11. The electrical contactor of claim 10 further comprising a travel limit post extending from the fixed plate through an elongated slot defined by the rotating plate, and configured to stop the rotating plate as the rotating plate moves from the open position to the closed position and vice-versa.
12. The electrical contactor of claim 10 , wherein the first, second, and third magnets are spaced away from a pin by a first distance, and wherein an elongated slot defined by the rotating plate is spaced away from the pin by a second distance greater than the first.
13. The electrical contactor of claim 10 further comprising an electromechanical actuator configured to move the rotating plate between the open and closed positions.
14. The electrical contactor of claim 10 further comprising a spring connected to the rotating plate, and configured to bias the rotating plate toward either the open position or the closed position.
15. The electrical contactor of claim 10 further comprising a high-voltage terminal electrically connected to the fixed plate, and configured to electrically connect a battery to the electrical contactor.
16. A method of operating an electrical contactor comprising:
opening the electrical contactor by,
moving a rotating plate, pivotally connected to a fixed plate by a pin defining an axis, in a first direction transverse to the axis; and
displacing the rotating plate in a second direction, along the axis, by a magnetic force exerted between a first magnet disposed within the rotating plate and a second magnet disposed within the fixed plate.
17. The method of claim 16 , wherein the moving is performed by powering a solenoid to displace a shaft connected to the rotating plate.
18. The method of claim 17 further comprising closing the electrical contactor by,
retracting the shaft to move the rotational plate in a third direction, opposite to the first; and
displacing the rotating plate in a fourth direction, opposite to the second direction, responsive to the first magnet being aligned with a third magnet disposed within the fixed plate.
19. The method of claim 18 , wherein the retracting is performed by biasing a return spring connected to the fixed plate and the rotating plate.