Neutral switching high speed AC transfer switch
AssigneeLayerZero Power Systems, Inc.
InventorsJames M. Galm, Ged Butkus, Milind M. Bhanoo
Life of this patent
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Abstract
A hybrid neutral transfer switch in an electrical system to transfer a load between multiple AC power sources is provided. The hybrid neutral transfer switch includes a neutral gate controlled device connected to a neutral input of each of the multiple power sources and a mechanical transfer switch that switches between the neutral input of each of the power sources. During the transfer of power from one power source to another power source, the neutral gate controlled devices are activated and/or deactivated in conjunction with the switching of the mechanical transfer switch from one neutral input to another neutral input.
Claims20
A neutral transfer switch in an electrical system to transfer a load between a plurality of AC power sources, the neutral transfer switch comprising:
- a gate controlled device connected to a neutral input of each of the plurality of power sources;
- a mechanical transfer switch switchably connected to the neutral input of each of the plurality of power sources;
- wherein when one of the plurality of power sources is active and supplying power to the load, the gate controlled device associated with the active power source is active, the mechanical transfer switch is connected to the neutral input of the active power source, the mechanical transfer switch is connected in parallel with the gate controlled device associated with the active power source, and current from the active power source is flowing through the mechanical transfer switch to the load.
A hybrid transfer switch in an electrical system to transfer a load from a first power source to a second power source, the hybrid transfer switch comprising:
- a first gate controlled device connected to the first power source;
- a second gate controlled device connected to the second power source;
- a mechanical transfer switch switchably connected to the first power source and the second power source,
- wherein when the first power source is supplying power to the load, the first gate controlled device is active, the mechanical transfer switch is connected to the first power source, the mechanical transfer switch is connected in parallel with the first gate controlled device, and current from the first power source is flowing through the mechanical transfer switch to the load, and
- wherein when the second power source is supplying power to the load, the second gate controlled device is active, the mechanical transfer switch is connected to the second power source, the mechanical transfer switch is connected in parallel with the second gate controlled device, and current from the second power source is flowing through the mechanical transfer switch to the load.
A switching apparatus to transfer power to a load from a first power source to a second power source comprising:
- a first set of phase gate controlled devices connected to a first set of phase inputs of the first power source;
- a second set of phase gate controlled devices connected to a second set of phase inputs of the second power source;
- a first neutral gate controlled device connected to a first neutral input of the first power source;
- a second neutral gate controlled device connected to a second neutral input of the second power source;
- a mechanical transfer switch switchably connected to the first neutral input of the first power source and the second neutral input of the second power source,
- wherein when the first power source is supplying power to the load, the first neutral gate controlled device is active, the mechanical transfer switch is connected to the first neutral input of the first power source, the mechanical transfer switch is connected in parallel with the first neutral gate controlled device, and current from the first neutral input of the first power source is flowing through the mechanical transfer switch to the load, and
- wherein when the second power source is supplying power to the load, the second neutral gate controlled device is active, the mechanical transfer switch is connected to the second neutral input of the second power source, the mechanical transfer switch is connected in parallel with the second neutral gate controlled device, and current from the second neutral input of the second power source is flowing through the mechanical transfer switch to the load.
A method to transfer power to a load from an active power source to an inactive power source comprising:
- at time t0
- initiating a transfer of a mechanical transfer switch;
- deactivating an active set of gate controlled devices connected to a first set of inputs of the active power source;
- activating an inactive neutral gate controlled device connected to a neutral input of the inactive power source;
- at time t1
- activating an inactive set of phase gate controlled devices connected to a second set of phase inputs of the inactive power source;
- at time t2
- disconnecting the mechanical transfer switch from a neutral input of the active power source or connecting the mechanical transfer switch to the neutral input of the inactive power source;
- and
- at time t3
- connecting the mechanical transfer switch to the neutral input of the inactive power source or disconnecting the mechanical transfer switch from a neutral input of the active power source.
Dependencies are inferred from the claim text.