Method for the overlap-free transfer of electric power sources and source changeover switch implementing such a method

Patent metadata

Field	Value
Publication number	US-11063468-B2
Application number	US-201916456088-A
Country	US
Kind code	B2
Filing date	Jun 28, 2019
Priority date	Aug 9, 2018
Publication date	Jul 13, 2021
Grant date	Jul 13, 2021

Abstract

The invention relates to a method for transferring, during a predetermined transfer duration, the electric power supply of an electric distribution line (7) from a first source (1) to a second source (2), without overlapping of the two sources.The invention also relates to a source inverter implementing such a method.

First claim

The invention claimed is:

1. A method for transferring, during a predetermined transfer duration, an electric power supply of an electric distribution line from a first source to a second source, without overlapping of the two sources, wherein a first switch, which is connected, on the one hand, to the first source and, on the other hand, to the distribution line, being commanded to close or open in order to connect or disconnect the first source to/from the distribution line, a second switch, which is connected, on the one hand, to the second source and, on the other hand, to the distribution line, being commanded to close or open in order to connect or disconnect the second source to/from said distribution line, the method comprising:
applying either a first delay time before a command for opening the first switch or applying a second delay time before a command for closing the second switch; and
computing the first delay time or the second delay time so that a time interval between a disconnection of the first source and a connection of the second source is equal to the transfer duration.

2. The method according to claim 1 , further comprising a step of computing:
an average value of a first operation duration for connecting the first source to the distribution line;
an average value of a second operation duration for connecting the second source to the distribution line;
an average value of a third operation duration for disconnecting the first source from the distribution line; and
an average value of a fourth operation duration for disconnecting the second source from the distribution line.

3. The method according to claim 2 , wherein the first delay time is applied before the command to open the first switch, when the second operation duration for connecting the second source is greater than a sum of the third operation duration for disconnecting the first source and of the transfer duration.

4. The method according to claim 3 , wherein the first delay time is equal to the second operation duration for connecting the second source, less the sum of the third operation duration for disconnecting the first source and of the transfer duration.

5. The method according to claim 2 , wherein the second delay time is applied before the command to close the second switch, when the second operation duration for connecting the second source is less than the sum of the third operation duration for disconnecting the first source and of the transfer duration.

6. The method according to claim 5 , wherein the second delay time is equal to the sum of the third operation duration for disconnecting the first source and of the transfer duration, less the second operation duration for connecting the second source.

7. The method according to claim 1 , wherein the transfer duration is between 10 ms and 50 ms.

8. The method according to claim 1 , wherein an observation window of a predetermined observation duration is opened at the same time as the command to close the second switch.

9. The method according to claim 8 , wherein the opening of the second switch is commanded when a closure indicator of the second switch is not delivered during the observation duration.

10. The method according to claim 9 , wherein the closure indicator of the second switch is delivered during execution of a movement to close contacts of said second switch.

11. The method according to claim 9 , characterized in that the closure indicator of the second switch is delivered when contacts of said second switch are closed.

12. The method according to claim 9 , wherein the closure indicator of the second switch is delivered when contacts of said second switch are no longer open.

13. A source inverter intended to command at least one first switch and one second switch for transferring, during a predetermined transfer duration, without overlapping, the electric power supply of a power distribution line from a first source to a second source, the first switch comprising at least:
one first closure actuator for commanding a closure operation of the first switch;
one first opening actuator for commanding an opening operation of the first switch; and
one first sensor for supplying a first signal indicating the closure of the first switch,
the second switch comprising at least:
one second closure actuator for commanding a closure operation of the second switch;
one second opening actuator; and
one second sensor for supplying a second signal indicating the closure of the second switch,
the source inverter comprising:
at least one first connection connected to the first sensor for receiving a first signal indicating the closure of the first switch and one second connection for receiving a second signal indicating the closure of the second switch;
at least one third connection for commanding the first opening actuator and one fourth connection for commanding the second opening actuator;
at least one fifth connection for commanding the first closure actuator for commanding the second closure actuator; and
a processing unit configured to
apply either a first delay time before a command for opening the first switch or applying a second delay time before a command for closing the second switch, and
compute the first delay time or the second delay time so that a time interval between a disconnection of the first source and a connection of the second source is equal to the transfer duration.

14. The source inverter according to claim 13 , wherein the first and second closure actuators of the first and second switches are activated by a direct voltage and in that the source inverter.

15. The source inverter according to claim 13 , wherein the first and second opening actuators of the first and second switches are activated by a direct voltage and the source inverter transmits a direct voltage over the third and fourth connections for respectively commanding the first and second opening actuators of the first and of the second switch.

16. An electric switch intended to be commanded by a source inverter according to claim 13 , said electric switch comprising at least:
one upstream connection terminal intended to be connected to a source supplying electric power;
one downstream connection terminal intended to be connected to an electric power distribution line;
electric contacts for establishing or interrupting the circulation of power between at least the upstream terminal and the downstream terminal;
for activating a mechanism for opening the electric contacts;
a closure actuator for activating a mechanism for closing the electric contacts;
said electric switch being characterized in that the activation of the mechanism for opening the electric contacts acts on the mechanism for closing the contacts in order to interrupt a closure movement of said contacts.

Assignees

• Schneider Electric Ind Sas

Inventors

• Belletto Jean-Luc
• Reymond Pascal

Classifications

• H02J3/007

  Arrangements for selectively connecting one or more loads to one or more power sources or power lines · CPC title

• H02J9/061 Primary

  for DC powered loads · CPC title

• H01H9/56

  for ensuring operation of the switch at a predetermined point in the AC cycle · CPC title

• H02J9/062 Primary

  for AC powered loads · CPC title

• H02J9/068

  Electronic means for switching from one power supply to another power supply, e.g. to avoid parallel connection · CPC title