Method for visualization of transmission flow in a system, an operator terminal and a supervisory control system

1. A method for visualizing on a display unit of an operator terminal a transmission flow in a system comprising a power network, the method comprising the steps of:

retrieving a starting point and an end point of said transmission flow;

retrieving a length of time during which said transmission flow has been active in said system;

generating a picture with a geometrical line overlaid on a background, wherein the geometrical line, from said starting point to said end point, represents a power line and also graphically represents said transmission flow, wherein a direction of said transmission flow is graphically represented by a continuously increased opacity of said geometrical line between said starting point and said end point of said transmission flow with an opacity level starting at a distance from the end point on the line that is increasing with increasing length of time in said direction of said transmission flow; and

outputting said picture on said display unit.

2. The method as claimed in claim 1 , wherein said opacity level reaches its maximum when said length of time exceeds a predefined limit.

3. The method as claimed in claim 1 , wherein said step of retrieving said length of time and said step of generating said picture is performed repeatedly.

4. The method as claimed in claim 1 , further comprising the steps of:

retrieving a capacity value of said transmission flow; and

generating said picture with the width of said geometrical line corresponding to said capacity value.

5. The method as claimed in claim 4 , further comprising the steps of:

retrieving a load percentage value of said transmission line; and

generating said picture with said geometrical line being graphically represented by a pair of inner lines having a first width there between, and a pair of outer lines having a second width there between, wherein said first width is determined and mapped in correspondence with said load percentage value and wherein said second width is determined and mapped in relation to said capacity value.

6. The method as claimed in claim 1 , further comprising the step of:

generating said picture by embedding at least one arrow into said geometrical line with said arrow pointing from said end point to said starting point of the transmission flow, thereby indicating the direction of said transmission flow.

7. The method as claimed in claim 1 , wherein said transmission flow comprises flow of real power of a power line of said power network.

8. An operator terminal of a supervisory control system comprising:

a user input unit,

a display unit and

a control unit configured to

retrieve a starting point and an end point of said transmission flow,

retrieve a length of time during which said transmission flow has been active in said system,

generate a picture with a geometrical line overlaid on a background, wherein the geometrical line, from said starting point to said end point, represents a power line and also graphically represents said transmission flow, wherein a direction of said transmission flow is graphically represented by a continuously increased opacity of said geometrical line between said starting point and said end point of said transmission flow with an opacity level starting at a distance from the end point on the line that is increasing with increasing length of time in said direction of said transmission flow, and

output said picture on said display unit.

9. A supervisory control system for supervising a system comprising a power network, said system comprising system interface units configured to take measurements from and perform control actions on said system, said supervisory control system comprising a processing device for processing signals received from or sent out to said system interface units, a data storage device configured to store said measurements and data generated by said processing device from the processing of measurements and an operator terminal as claimed in claim 8 .

10. The method as claimed in claim 2 , wherein said step of retrieving said length of time and said step of generating said picture is performed repeatedly.

11. The method as claimed in claim 2 , further comprising the steps of:

retrieving a capacity value of said transmission flow; and

generating said picture with the width of said geometrical line corresponding to said capacity value.

12. The method as claimed in claim 3 , comprising the further steps of:

retrieving a capacity value of said transmission flow; and

generating said picture with the width of said geometrical line corresponding to said capacity value.

13. The method as claimed in claim 2 , comprising the further step of:

generating said picture by embedding at least one arrow into said geometrical line with said arrow pointing from said end point to said starting point of the transmission flow, thereby indicating the direction of said transmission flow.

14. The method as claimed in claim 3 , comprising the further step of:

generating said picture by embedding at least one arrow into said geometrical line with said arrow pointing from said end point to said starting point of the transmission flow, thereby indicating the direction of said transmission flow.

15. The method as claimed in claim 4 , comprising the further step of:

generating said picture by embedding at least one arrow into said geometrical line with said arrow pointing from said end point to said starting point of the transmission flow, thereby indicating the direction of said transmission flow.

16. The method as claimed in claim 5 , comprising the further step of:

generating said picture by embedding at least one arrow into said geometrical line with said arrow pointing from said end point to said starting point of the transmission flow, thereby indicating the direction of said transmission flow.

17. The method as claimed in claim 2 , wherein said transmission flow comprises flow of real power of a power line of said power network.

18. The method as claimed in claim 3 , wherein said transmission flow comprises flow of real power of a power line of said power network.

19. The method as claimed in claim 4 , wherein said transmission flow comprises flow of real power of a power line of said power network.

20. The method as claimed in claim 5 , wherein said transmission flow comprises flow of real power of a power line of said power network.