Method of controlling a cyclically commutated hydraulic pump

1. A method of operating a fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection and at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection, wherein the pumping and/or motoring strokes of said working chamber are controlled by an appropriate actuation of said electrically actuated valve, wherein the actuation of said electrically actuated valve is modified by a time evolvement function, taking into account the time evolvement of the fluid flow demand on the high-pressure side and/or the time evolvement of said working chamber's pumping/motoring strokes, wherein the time evolvement function comprises a vectorised variable being indicative of the time dependency of the fluid output flow during a pumping stroke.

2. The method according to claim 1 , wherein the time evolvement function is able to trigger a pumping/motoring stroke for a plurality of working chambers and/or at a plurality of phases of each working chamber's working cycle.

3. The method according to claim 1 , wherein the time evolvement function comprises a spacing function, so that successive pumping/motoring strokes, particularly the peak output phases of successive pumping/motoring strokes, are spaced in time in a way to smooth the fluid output flow to said high-pressure fluid manifold.

4. The method according to claim 1 , wherein the time evolvement function comprises a variable being indicative of a fluid flow demand, wherein a threshold level of said variable is chosen in a way that a pumping/motoring stroke is initiated in advance of the actual demand.

5. The method according to claim 1 , wherein a plurality of electrically actuated valves are controlled.

6. The method according to claim 1 , wherein the pumping/motoring strokes, in particular the initiation of the pumping/motoring strokes of said working chambers are out of phase to each other.

7. A fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection, at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection and at least an electronic controller unit, wherein the electronic controller unit comprises a time evolvement consideration means that is designed and arranged in a way, that the electronic controller unit performs a method according to claim 1 .

8. A method of operating a fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection and at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection, wherein the pumping and/or motoring strokes of said working chamber are controlled by an appropriate actuation of said electrically actuated valve, wherein the actuation of said electrically actuated valve is modified by a time evolvement function, taking into account the time evolvement of the fluid flow demand on the high-pressure side and/or the time evolvement of said working chamber's pumping/motoring strokes, wherein the time evolvement function comprises a variable being indicative of a fluid flow demand, wherein a threshold level of said variable is chosen in a way that a pumping/motoring stroke is initiated in advance of the actual demand.

9. The method according to claim 8 , wherein the time evolvement function is able to trigger a pumping/motoring stroke for a plurality of working chambers and/or at a plurality of phases of each working chamber's working cycle.

10. The method according to claim 8 , wherein the time evolvement function comprises a spacing function, so that successive pumping/motoring strokes, particularly the peak output phases of successive pumping/motoring strokes, are spaced in time in a way to smooth the fluid output flow to said high-pressure fluid manifold.

11. The method according to claim 8 , wherein the time evolvement function comprises a vectorised variable being indicative of the time dependency of the fluid output flow during a pumping stroke.

12. The method according to claim 8 , wherein a plurality of electrically actuated valves are controlled.

13. The method according to claim 8 , wherein the pumping/motoring strokes, in particular the initiation of the pumping/motoring strokes of said working chambers are out of phase to each other.

14. A fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection, at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection and at least an electronic controller unit, wherein the electronic controller unit comprises a time evolvement consideration means that is designed and arranged in a way, that the electronic controller unit performs a method according to claim 8 .

15. A method of operating a fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection and at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection, wherein the pumping and/or motoring strokes of said working chamber are controlled by an appropriate actuation of said electrically actuated valve, wherein the actuation of said electrically actuated valve is modified by a time evolvement function, taking into account the time evolvement of the fluid flow demand on the high-pressure side and/or the time evolvement of said working chamber's pumping/motoring strokes, wherein the time evolvement function is able to decide on triggering a pumping/motoring stroke at a plurality of phases of each working chamber's working cycle.

16. The method according to claim 15 , wherein the time evolvement function is able to trigger a pumping/motoring stroke for a plurality of working chambers.

17. The method according to claim 16 , wherein the time evolvement function is able to trigger essentially simultaneously a plurality of pumping/motoring strokes for a plurality of working chambers.

18. The method according to claim 16 , wherein at least two of the plurality of working chambers are in different phases of their respective working cycle.

19. The method according to claim 15 , wherein the time evolvement function comprises a spacing function, so that successive pumping/motoring strokes, particularly the peak output phases of successive pumping/motoring strokes, are spaced in time in a way to smooth the fluid output flow to said high-pressure fluid manifold.

20. The method according to claim 15 , wherein the time evolvement function comprises a vectorised variable being indicative of the time dependency of the fluid output flow during a pumping stroke.

21. The method according to claim 15 , wherein the time evolvement function comprises a variable being indicative of a fluid flow demand, wherein a threshold level of said variable is chosen in a way that a pumping/motoring stroke is initiated in advance of the actual demand.

22. The method according to claim 15 , wherein a plurality of electrically actuated valves are controlled.

23. The method according to claim 15 , wherein the pumping/motoring strokes, in particular the initiation of the pumping/motoring strokes of said working chambers are out of phase to each other.

24. A fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection, at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection and at least an electronic controller unit, wherein the electronic controller unit comprises a time evolvement consideration means that is designed and arranged in a way, that the electronic controller unit performs a method according to claim 15 .

25. A method of operating a fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection and at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection, wherein the pumping and/or motoring strokes of said working chamber are controlled by an appropriate actuation of said electrically actuated valve, wherein the actuation of said electrically actuated valve is modified by a time evolvement function, taking into account the time evolvement of the fluid flow demand on the high-pressure side and/or the time evolvement of said working chamber's pumping/motoring strokes, wherein the time evolvement function comprises a spacing function, so that successive pumping/motoring strokes are spaced in time in a way to smooth the fluid output flow to said high-pressure fluid manifold.

26. The method according to claim 25 , wherein the time evolvement function is able to trigger a pumping/motoring stroke for a plurality of working chambers and/or at a plurality of phases of each working chamber's working cycle.

27. The method according to claim 25 , wherein the time evolvement function comprises a spacing function, so that the peak output phases of successive pumping/motoring strokes are spaced in time in a way to smooth the fluid output flow to said high-pressure fluid manifold.

28. The method according to claim 25 , wherein the time evolvement function comprises a vectorised variable being indicative of the time dependency of the fluid output flow during a pumping stroke.

29. The method according to claim 25 , wherein the time evolvement function comprises a variable being indicative of a fluid flow demand, wherein a threshold level of said variable is chosen in a way that a pumping/motoring stroke is initiated in advance of the actual demand.

30. The method according to claim 25 , wherein a plurality of electrically actuated valves are controlled.

31. The method according to claim 25 , wherein the pumping/motoring strokes, in particular the initiation of the pumping/motoring strokes of said working chambers are out of phase to each other.

32. A fluid working machine, comprising at least one working chamber of cyclically changing volume, a high-pressure fluid connection, a low-pressure fluid connection, at least one electrically actuated valve connecting said working chamber to said high-pressure fluid connection and/or said low-pressure fluid connection and at least an electronic controller unit, wherein the electronic controller unit comprises a time evolvement consideration means that is designed and arranged in a way, that the electronic controller unit performs a method according to claim 25 .