MOSFET based, high voltage, electronic relays for AC power switching and inductive loads
View Patent ↗A MOSFET based, high voltage, high current AC electronic relay operating with normally closed contacts is disclosed. The relay includes at least one MOSFET switching circuit selectively switching between switch conducting and switch isolation. The at least one MOSFET switching circuit is normally closed and includes a plurality of inputs controlling the operation thereof. The plurality of inputs are connected to at least one rectifier such that a voltage differential exists between any two inputs of the MOSFET switching circuit providing a voltage source maintaining the MOSFET switching circuit normally closed. The relay also includes a control circuit linked to and controlling operation of the first transformer and second transformer. A switch for use in controlling operation of a MOSFET based, high voltage, high current AC electronic relay is also disclosed. The switch includes a key and a receptacle for selectively receiving the key at various positions. The receptacle includes a plurality of contacts for selective engagement with the key. The contacts includes first and second common contacts connecting to a common terminal, first and second relay block contacts connecting to a relay block, a normally closed contact coupled to a normally closed terminal and a normally open contact coupled to a normally open terminal. In use, the key is selectively positioned within the receptacle for placing the relay in an automatic mode, a normal mode or an energized mode.
1. A MOSFET based, high voltage, high current AC electronic relay operating with normally closed contacts, comprising:
at least one power MOSFET switching circuit selectively switching between switch conducting and switch isolation, the power MOSFET switching circuit being normally closed and including a plurality of inputs controlling the operation thereof;
a driving circuit being connected to the power MOSFET switching circuit via at least one rectifier coupled to the plurality of inputs such that a voltage differential exists between any two inputs of the power MOSFET switching circuit provide a voltage source maintaining the power MOSFET switching circuit normally closed;
a control circuit linked to and controlling operation of the power MOSFET switching circuit; and
a first transformer coupled to the power MOSFET switching circuit, the first transformer selectively applying a predetermined first voltage to the power MOSFET switching circuit which establishes the power MOSFET switching circuit in switch conducting; and a second transformer coupled to the power MOSFET switching circuit, the second transformer selectively applying a predetermined second voltage to the power MOSFET switching circuit which establishes the power MOSFET switching circuit in switch isolation in an expedited manner; and wherein the control circuit is linked to and controls the operation of the first and second transformers.
2. The electronic relay according to claim 1 , wherein the first transformer is associated with a first rectifier and the second transformer is associated with a second rectifier.
3. The electronic relay according to claim 1 , further including a power supply connected to the first transformer, the second transformer and the control circuit.
4. The electronic relay according to claim 1 , wherein the power MOSFET switching circuit includes first and second power MOSFETs electrically connected to the first transformer for selectively establishing switch conducting upon application of a predetermined first voltage by the first transformer.
5. The electronic relay according to claim 4 , wherein a first rectifier is associated with inputs of the first power MOSFET and a second rectifier is associated with inputs of the second power MOSFET.
6. The electronic relay according to claim 4 , wherein the power MOSFET switching circuit includes third and fourth MOSFETs electrically connected to the second transformer for selectively establishing switch isolation upon the application of a predetermined second voltage by the second transformer.
7. The electronic relay according to claim 6 , wherein a first rectifier is associated with inputs of the first power MOSFET, a second rectifier is associated with inputs of the second power MOSFET, a third rectifier is associated with inputs of the third MOSFET and a fourth rectifier is associated with inputs of the fourth MOSFET.
8. A MOSFET based, high voltage, high current AC electronic relay operating with normally closed contacts, comprising:
at least one MOSFET switching circuit selectively switching between switch conducting and switch isolation, the MOSFET switching circuit being normally closed and including a plurality of inputs controlling the operation thereof;
a first transformer including a primary winding connected to an AC driving circuit and a secondary winding, the secondary winding being coupled to the MOSFET switching circuit via a first rectifier coupled to the plurality of inputs such that a voltage differential exists between any two inputs of the MOSFET switching circuit provide a voltage source maintaining the MOSFET switching circuit normally closed, and wherein the first transformer selectively applies a predetermined first voltage to the MOSFET switching circuit which establishes the MOSFET switching circuit in switch conducting;
a second transformer is coupled to the MOSFET switching circuit, the second transformer selectively applying a predetermined second voltage to the MOSFET switching circuit which establishes the MOSFET switching circuit in switch isolation in an expedited manner; and
a control circuit linked to and controlling operation of the MOSFET switching circuit, the control circuit being further linked to and controlling operation of the first and second transformers.
9. The electronic relay according to claim 8 , wherein the second transformer is associated with a second rectifier.
10. The electronic relay according to claim 8 , wherein the MOSFET switching circuit includes first and second MOSFETs electrically connected to the first transformer for selectively establishing switch conducting upon application of a predetermined first voltage by the first transformer.
11. The electronic relay according to claim 10 , wherein the first rectifier is associated with inputs of the first MOSFET and a second rectifier is associated with inputs of the second MOSFET.
12. The electronic relay according to claim 10 , wherein the MOSFET switching circuit includes third and fourth MOSFETs electrically connected to the second transformer for selectively establishing switch isolation upon the application of a predetermined second voltage by the second transformer.
13. A MOSFET based, high voltage, high current AC electronic relay operating with normally closed contacts, comprising:
at least one MOSFET switching circuit selectively switching between switch conducting and switch isolation, the MOSFET switching circuit being normally closed and including a plurality of inputs controlling the operation thereof, the MOSFET switching circuit including a first MOSFET and a second MOSFETs;
a driving circuit coupled to the MOSFET switching circuit via a first rectifier coupled to the plurality of inputs such that a voltage differential exists between any two inputs of the MOSFET switching circuit provide a voltage source maintaining the MOSFET switching circuit normally closed;
a control circuit linked to and controlling operation of the MOSFET switching circuit; and
a first transformer coupled to the MOSFET switching circuit, the first transformer selectively applying a predetermined first voltage to the MOSFET switching circuit which establishes the MOSFET switching circuit in switch conducting; and a second transformer coupled to the MOSFET switching circuit, the second transformer selectively applying a predetermined second voltage to the MOSFET switching circuit which establishes the MOSFET switching circuit in switch isolation in an expedited manner; and wherein the control circuit is linked to and controls the operation of the first and second transformers.
14. The electronic relay according to claim 13 , wherein the first transformer is associated with the first rectifier and the second transformer is associated with a second rectifier.
15. The electronic relay according to claim 14 , wherein the first and second MOSFETs are electrically connected to the first transformer for selectively establishing switch conducting upon application of a predetermined first voltage by the first transformer.
16. The electronic relay according to claim 15 , wherein the first rectifier is associated with inputs of the first MOSFET and the second rectifier is associated with inputs of the second MOSFET.
17. The electronic relay according to claim 15 , wherein the MOSFET switching circuit includes third and fourth MOSFETs electrically connected to the second transformer for selectively establishing switch isolation upon the application of a predetermined second voltage by the second transformer.