Adaptive flux band for improving transfer times in a static transfer switch

1 . A transfer switch system for transferring power from a first power source to a second power source, the transfer switch system comprising:

one or more sensors configured to detect an electrical measurement associated with powering a load between the first power source, the second power source, and a downstream transformer;

one or more semiconductor switch assemblies, the first power source and the second power source associated with a different semiconductor switch assembly of the one or more semiconductor switch assemblies; and

a controller configured to:

obtain a transfer time for transferring the power from the first power source to the second power source;

obtain an inrush current not to be exceeded during transfer of the power from the first power source to the second power source;

determine a phase difference between the first power source and the second power source based on electrical measurements from the first power source and the second power source, obtained by the one or more sensors;

disconnect the first power source from the load based on a detected disturbance with the first power source supplying the load, the detected disturbance determined based on the electrical measurements from the first power source obtained by the one or more sensors, the disconnect of the first power source executed by instructing, by the controller, the corresponding semiconductor switch assembly of the first power source to turn off;

determine one or more flux bands based on the phase difference, the transfer time, and the inrush current; and

initiate a first connection between the second power source and the load by instructing each switch of the corresponding semiconductor switch assembly of the second power source to turn on at certain times based on flux matching using the determined one or more flux bands.

2 . The transfer switch system according to claim 1 , wherein the one or more semiconductor switch assemblies comprise at least one of silicon-controlled rectifiers (SCRs), insulate gate bipolar transistors (IGBTs), metal-oxide-semiconductors (MOSFETs), integrated gate-commutated thyristors (IGCTs), and gate turn-off thyristors (GTOs).

3 . The transfer switch system according to claim 1 , further comprising the downstream transformer, wherein the first power source and the second power source are configured to provide the power to the load via the downstream transformer.

4 . The transfer switch system according to claim 1 , wherein the transfer time and the inrush current are user specified.

5 . The transfer switch system according to claim 1 , wherein the controller is further configured to:

determine an updated phase difference between the first power source and the second power source based on the electrical measurements from the first power source, the second power source, and the downstream transformer obtained by the one or more sensors;

disconnect the second power source from the load based on an updated detected disturbance with the second power source providing the load, the updated detected disturbance based on the electrical measurements from the second power source obtained by the one or more sensors, the disconnect of the second power source executed by instructing, by the controller, the corresponding semiconductor switch assembly of the second power source to turn off;

determine updated one or more flux bands based on the updated phase difference, the transfer time, and the inrush current; and

initiate a second connection between the first power source and the load by instructing each switch of the corresponding semiconductor switch assembly of the first power source to turn on at certain times based on the updated one or more flux bands.

6 . The transfer switch system according to claim 1 , wherein the one or more flux bands are updated as the first connection is initiated and as a first portion of switches of the corresponding semiconductor switch assembly of the second power source are turned on by adjusting the phase difference between the second power source and the downstream transformer based on updated electrical measurements from the second power source and the downstream transformer obtained by the one or more sensors.

7 . The transfer switch system according to claim 1 , wherein each switch or a set of switches of the semiconductor switch assemblies is associated with a different phase of an A/C voltage supplied to the load.

8 . The transfer system according to claim 1 , wherein the transfer time and the inrush current are limited by using characteristics of the downstream transformer.

9 . The transfer system according to claim 1 , wherein the controller is further configured to adjust the transfer time and the inrush current based on characteristics of the downstream transformer.

10 . The transfer system according to claim 1 , wherein the controller is further configured to:

obtain an actual transfer time for transferring the power from the first power source to the second power source derived from initiating a transfer; and

adjust the one or more flux bands based on the actual transfer time.

11 . A tangible, non-transitory computer-readable medium having instructions thereon which, upon being executed by one or more processors, provide for transferring power from a first power source to a second power source by execution of the following steps:

obtaining a transfer time for transferring the power from the first power source to the second power source;

obtaining an inrush current not to be exceeded during transfer of the power from the first power source to the second power source;

determining a phase difference between the first power source and the second power source based on electrical measurements from the first power source and the second power source, obtained by one or more sensors;

disconnecting the first power source from a load based on a detected disturbance with the first power source supplying the load, the detected disturbance determined based on the electrical measurements from the first power source obtained by the one or more sensors, the disconnect of the first power source executed by instructing a corresponding semiconductor switch assembly of the first power source to turn off;

determining one or more flux bands based on the phase difference, the transfer time, and the inrush current; and

initiating a first connection between the second power source and the load by instructing each switch of a corresponding semiconductor switch assembly of the second power source to turn on at certain times based on flux matching using the determined one or more flux bands.

12 . The tangible, non-transitory computer-readable medium according to claim 11 , wherein the transfer time and the inrush current are user specified.

13 . The tangible, non-transitory computer-readable medium according to claim 11 , wherein the instructions, upon being executed by the one or more processors, are further configured to execute the following steps:

determining an updated phase difference between the first power source and the second power source based on the electrical measurements from the first power source, the second power source, and an associated downstream transformer obtained by the one or more sensors;

disconnecting the second power source from the load based on an updated detected disturbance with the second power source providing the load, the updated detected disturbance based on the electrical measurements from the second power source obtained by the one or more sensors, the disconnect of the second power source executed by instructing the corresponding semiconductor switch assembly of the second power source to turn off;

determining updated one or more flux bands based on the updated phase difference, the transfer time, and the inrush current; and

initiating a second connection between the first power source and the load by instructing each switch of the corresponding semiconductor switch assembly of the first power source to turn on at certain times based on the updated one or more flux bands.

14 . The tangible, non-transitory computer-readable medium according to claim 11 , wherein the one or more flux bands are updated as the first connection is initiated and as a first portion of switches of the corresponding semiconductor switch assembly of the second power source are turned on by adjusting the phase difference between the second power source and an associated downstream transformer based on updated electrical measurements from the second power source and the associated downstream transformer obtained by the one or more sensors.

15 . The tangible, non-transitory computer-readable medium according to claim 11 , wherein each switch or a set of switches of the corresponding semiconductor switch assemblies is associated with a different phase of an A/C voltage supplied to the load.

16 . The tangible, non-transitory computer-readable medium according to claim 11 , wherein the transfer time and the inrush current are limited by using characteristics of an associated downstream transformer.

17 . The tangible, non-transitory computer-readable medium according to claim 11 , wherein the instructions, upon being executed by the one or more processors, are further configured to execute the following steps: adjusting the transfer time and the inrush current based on characteristics of an associated downstream transformer.

18 . The tangible, non-transitory computer-readable medium according to claim 11 , wherein the instructions, upon being executed by the one or more processors, are further configured to execute the following steps:

obtaining an actual transfer time for transferring the power from the first power source to the second power source derived from initiating a transfer; and

adjusting the one or more flux bands based on the actual transfer time.

19 . A computer-implemented method for transferring power from a first power source to a second power source, comprising:

obtaining a transfer time for transferring the power from the first power source to the second power source;

obtaining an inrush current not to be exceeded during transfer of the power from the first power source to the second power source;

determining a phase difference between the first power source and the second power source based on electrical measurements from the first power source and the second power source, obtained by one or more sensors;

disconnecting the first power source from a load based on a detected disturbance with the first power source supplying the load, the detected disturbance determined based on the electrical measurements from the first power source obtained by the one or more sensors, the disconnect of the first power source executed by instructing a corresponding semiconductor switch assembly of the first power source to turn off;

determining one or more flux bands based on the phase difference, the transfer time, and the inrush current; and

initiating a first connection between the second power source and the load by instructing each switch of a corresponding semiconductor switch assembly of the second power source to turn on at certain times based on flux matching using the determined one or more flux bands.

20 . The computer-implemented method according to claim 19 , wherein the one or more flux bands are updated as the first connection is initiated and as a first portion of switches of the corresponding semiconductor switch assembly of the second power source are turned on by adjusting the phase difference between the second power source and an associated downstream transformer based on updated electrical measurements from the second power source and the associated downstream transformer obtained by the one or more sensors.