Method for controlling a load suspended by a hoisting wire

Abstract

Method for controlling a load (100) suspended by a hoisting wire (19) of a crane. The crane comprises a boom (20) with two front main chords. The crane further comprises a tagline system, wherein the tagline system comprises two tagline trolleys (31, 32) which travel along the boom (19). A tagline (33, 34) extends from each tagline trolley to a load and / or load connector. The tagline control system (200) determines a required (un)winding based on a hoist signal, the length of the tagline trolley cables, the length of the taglines, and the geometry of the boom.

Description

[0001] P37065PC00

[0002] METHOD FOR CONTROLLING A LOAD SUSPENDED BY A HOISTING WIRE

[0003] The present invention relates to a method for controlling a load suspended from a hoisting wire of a crane, wherein use is made of a tagline system.

[0004] It is known to provide a crane with a tagline system to enhance the control of motion, position, and / or orientation of the load.

[0005] For example, tagline systems are commonly used in the wind industry to provide a constant orientation of the wind turbine blade while the blade is being hoisted to an installation height. When the blade is at the installation height the tagline system is commonly used to stabilize and / or change the orientation of the blade for alignment with the blade mounting structure of the hub of the wind turbine.

[0006] Examples of crane having a tagline system are presented in WO2024083833, EP1925582, and EP2490975. The cranes commonly comprise: a base structure, e.g. adapted to be mounted on a vessel, a revolving structure slewable on a slew bearing about a vertical slew axis relative to the base structure, a boom which is at the inner end thereof pivotally connected to the revolving structure, wherein the boom can pivot about a horizontal pivot axis, a luffing device for pivoting the boom about the horizontal pivot axis, wherein the luffing device comprises a luffing winch and a variable length luffing system, a hoisting winch, a hoisting wire driveable by the hoisting winch, and a load connector suspended from the boom via the hoisting wire. In operation, the load connector is connected to the load.

[0007] For example, the boom is embodied as a latticed hollow box structure comprising two front main chords at a front side of the boom and two rear main chords at a rear side of the boom.

[0008] Known tagline systems comprise at least two taglines which are each driven by an associated tagline winch. In known embodiments, these taglines winches are placed on or nearby the crane such that the tagline extends from the tagline winch directly to the load. In other known embodiments, the tagline system comprises guide wires configured to be tensioned along the boom, wherein a trolley slides over a respective guide wire. The tagline then, for example, extends from the winch to a sheave of the trolley and then to the load. The trolleys can follow the motion of the load during hoisting or lowering, e.g. passively or driven by an associated trolley drive.

[0009] For example, a tagline system can be embodied as a stand-alone system which can be used in combination with different (types of) cranes. These stand-alone tagline systems commonly have a control system which operates independent of control system of the crane, e.g. of the hoist system of the crane.

[0010] In another known embodiment, the tagline trolley is mounted to the boom, e.g. on a rail mounted on the boom or directly on a chord of the boom.

[0011] It is known to have a trolley drive to move the tagline trolley up and down along the boom, e.g. such that the orientation of the tagline with respect to the load can be kept constant during hoisting / lowering, or varied as desired by an operator.

[0012] It is known to operate the tagline system so as to control the motion, position, and / or orientation of the load by changing the length of the taglines, this can be done manually as well as automatically.

[0013] The present invention aims to provide a more accurate and easy to implement control method for controlling a load suspended by a hoisting wire.

[0014] The present invention provides a method according to claim 1. The tagline system used to control the load comprises: two horizontal tagline trolley assemblies each comprise: o a tagline trolley which travels along the boom, preferably engages a respective one of the front main chords of the boom and is movable along the respective main chord, o a tagline trolley winch and a tagline trolley cable driven by the tagline trolley winch, wherein the tagline trolley is connected to the tagline trolley cable such that a (un)winding of the tagline trolley winch provides a controlled displacement of the tagline trolley along the boom, e.g. along the main front chord, two horizontal tagline assemblies, each horizontal tagline assembly comprising a tagline winch and a tagline driven by the tagline winch, wherein the tagline - in use of the crane - extends from a respective tagline trolley to the load and / or to the load connector.

[0015] The tagline system further comprises a tagline control system, wherein the tagline control system is configured to: receive a hoisting signal, e.g. from an operator, corresponding to the lifting or lowering of the suspended load by means of the hoisting winch, receive signals from the tagline trolley winches and the tagline winches corresponding to the unwound length of the tagline trolley cables and taglines respectively, send a tagline control signal to the tagline trolley winches and the tagline winches corresponding to a (un)winding speed of the tagline trolley winches and the tagline winches.

[0016] The method comprises the steps of: the tagline control system receiving a hoist signal, e.g. from an operator, corresponding to a lifting or lowering of the suspended load, the tagline control system receiving signals from each of the tagline trolley winches and each of the tagline winches corresponding to the unwound length of the tagline trolley cables and the taglines respectively, the tagline control system determining the required (un)winding speed of each of the tagline trolley winches and each of the taglines winches based on the hoist signal, the length of the tagline trolley cables, the length of the taglines, and the geometry of the boom, e.g. of the front main chords, the tagline control system sending a tagline control signal to each of the tagline trolley winches and each of the tagline winches,

[0017] (un)winding the hoist winch based on the hoist signal and (un)winding each of the tagline trolley winches and each of the tagline winches based on the respective the control signal.

[0018] The innovative control method enables precise and easy-to-implement load control.

[0019] Using the known unwound length of the tagline trolley cable, the exact position of each trolley can be determined.

[0020] In this system, tagline trolleys preferably engage the boom's front chords, which are rigid. Compared to systems where tagline trolleys are attached to guide wires running along the boom, this method allows for a more accurate determination of the tagline trolley cable’s position, resulting in improved load control. Even when the guide wires are tensioned, they provide a much less stable base for the tagline trolley then the chord of the boom or a rail for the tagline trolley mounted to the boom.

[0021] Additionally, because the tagline system is integrated with the crane, the tagline control system receives hoisting signals and has precise information about the crane's geometry. This setup enables the system to adjust the (un)winding speed of each winch as needed, without needing to rely on feedback from the winches or precise knowledge of the load’s position.

[0022] The term geometry of the boom relates to the structural and dimensional characteristics that define the spatial configuration and shape of the crane boom. The characteristics which define the geometry of the boom may be defined with respect to the revolving structure, the vessel (e.g. the hull), or a fixed point in space.

[0023] These characteristics may include, for example, the length of the front main chords over which the tagline trolleys travel, the orientation and direction of the chords, the horizontal distance or spacing between the front main chords along their length.

[0024] In a practical implementation, the geometry of the boom may be represented by defining the two front chords of the boom over which or along which (in case of tagline trolley rail being attached to the front chord) the tagline trolleys travel as three-dimensional vectors that capture both the position and orientation in space. In cases where the direction of the front chords or rails changes along the length of the boom, the geometry may be expressed as a set of vectors corresponding to successive front chord segments or rail segments. This allows the boom to be modelled with high precision, thereby enabling the control system to accurately calculate the spatial position and movement of the tagline trolley.

[0025] In an embodiment, the tagline trolley winches are set to have the trolleys follow the load during lifting / lowering, e.g. the orientation of the section of the taglines extending between the tagline trolley and the load / load connector remains constant seen in a side view, e.g. in a horizontal plane, this allows for an easier and more constant control of the load.

[0026] In an embodiment, the two front main chords of the boom are non-parallel with respect to each other. The tagline trolleys will therefore also not move parallel with respect to each other when they are moved along the main chords, this will also change the lateral position of the tagline trolleys with respect to the load, this needs to be accounted for when determining the required (un)winding speeds of the tagline trolley and tagline winches. Due to the tagline control system being integrated with the crane, and therefore knowing the exact geometry of the main chords, the tagline control system can determine the required (un)winding of each of the tagline trolley winches and each of the tagline winches to keep the orientation of the load stable or change it in a desired way.

[0027] In an embodiment, the tagline control system is configured to receive tagline control signals, e.g. from an operator, corresponding to an (un)winding of the tagline trolley winches and tagline winches, wherein the method comprises the steps of:

[0028] - the tagline control system determining the required (un)winding speed of each of the tagline trolley winches and each of the taglines winches based on the hoist signal, the length of the tagline trolley cables, the length of the taglines, the geometry of the front main chords, and on the received tagline control signals. This allows the operator to manually control the load during operation, for example for when the operator wants to change the orientation of the load.

[0029] In an embodiment, the tagline control system determines the required (un)winding speed of each of the tagline trolley winches and each of the taglines winches solely based on the received tagline control signals, e.g. a full manual control mode.

[0030] In an embodiment, the tagline control system is configured to receive tagline control signals from an input device, e.g. one or more joysticks configured to be used by an operator, wherein based on the inputs provided to the input device a tagline control signal corresponding to the (un)winding of the tagline trolley winches and / or tagline winches is send to the tagline control signals, which then sends a control signal to the tagline trolley winches and / or tagline winches. This can be done simultaneously, e.g. both tagline trolleys winches and / or tagline winches received the same control signal based on the input of the operator, or it can be done independently, e.g. each tagline trolley winch and / or tagline winch receives an independent control signal, e.g. to change the heights of the tagline trolleys with respect to each other, e.g. to change the orientation of the load.

[0031] In an embodiment, the tagline system comprises tension sensors which are configured to measure the tension of the taglines, wherein the control system is configured to receive signals from the tension sensors corresponding to the tension in the taglines.

[0032] In an embodiment, the method comprises the step of keeping a certain, e.g. predetermined, approximately, constant tension in the taglines during operation of the crane. This facilitates in keeping the load in a stable orientation and position. It is important to always have a certain tension in the taglines, otherwise the taglines cannot be used to control the load. In an embodiment, the tagline control system is configured to receive a signal representing the luffing angle of the crane boom, e.g. from the luffing device corresponding to the length of the variable length luffing system and / or the (un)winding of the luffing winch(es). Then the determination of the tagline control signal is also based on the luffing angle, e.g. on the received signal from the luffing device. The length of the variable length luffing system and / or the (un)winding of the luffing winch allows the control system to determine the luffing angle of the boom about the horizontal pivot axis with respect to the revolving structure. This allows the control system to determine and control the position and / or orientation of the load more accurately.

[0033] In an embodiment, the tagline control system is configured to unwind the tagline winch(es) if the tension in the tagline(s) goes over a pre-determined maximum tension, e.g. in case of a wind gust. This ensures that the tension in the taglines becomes too high and thereby damaging the crane. After the tension has gone down, the paid out length of the tagline(s) may then be wound back onto the winch(es).

[0034] In an embodiment, the tagline system further comprises: two vertical tagline assemblies, each vertical tagline assembly comprising a vertical tagline winch and a vertical tagline driven by the vertical tagline winch, wherein the vertical tagline- in use of the crane - extends from an outer end of the boom to the load and / or to the load connector, wherein the tagline control system is configured to receive signals from the vertical tagline winches corresponding to the unwound length of the vertical taglines, and wherein the tagline control system is configured to send control signals to the vertical tagline winches corresponding to an (un)winding speed of the vertical tagline winches, wherein the method comprises the steps of: the tagline control system receiving signals from each of the vertical tagline winches corresponding to the unwound length of the vertical tagline, the tagline control system determining the required (un)winding speed of each of the vertical taglines winches based on the hoist signal, the length of the tagline trolley cables, the length of the taglines, the length of the vertical taglines, and the geometry of the front main chords, and optionally on the tagline control signals, the tagline control system sending a tagline control signal to each of the vertical tagline winches, (un)winding the tagline winches based on the respective the control signal.

[0035] The vertical tagline assemblies further assist in the controlling of the load, allowing for changes of the orientation of the load in a vertical plane.

[0036] The invention also relates to a crane according to claim 8.

[0037] The invention will now be explained with reference to the figures. In the figures:

[0038] Fig. 1 shows a vessel provided with a crane comprising a tagline system,

[0039] Fig. 2 shows the tagline system,

[0040] Fig. 3 shows a block diagram of the tagline system.

[0041] Figure 1 shows a jack-op vessel 1 provided with a crane 10.

[0042] The crane 10 comprises a base structure 11 which is mounted on the deck 2 of the vessel 1.

[0043] The crane 10 further comprises a revolving structure 12 slewable on a slew bearing 13 about a vertical slew axis 14 relative to the base structure 12. A boom 20 is at the inner end thereof pivotally connected to the revolving structure 12. The boom 20 can pivot about a horizontal pivot axis.

[0044] The crane 10 has a luffing device 15 for pivoting the boom 20 about the horizontal pivot axis. The luffing device 15 comprises a luffing winch 16 and a variable length luffing system 17.

[0045] The crane 10 has a hoisting winch 18 and a hoisting wire 19 which is drivable by the hoisting winch.

[0046] A load connector 110 is suspended from the boom 20 via the hoisting wire 19, wherein the load connector 110 is connected to the load 100, here shown as a wind turbine blade.

[0047] The boom 20 is embodied as a latticed hollow box structure having two front main chords 21, 22 at a front side of the boom 20, and two rear main chords at a rear side of the boom 20.

[0048] The tagline system comprises: two horizontal tagline trolley assemblies each comprising: o a tagline trolley 31 , 32 which engages a respective one of the front main chords 21, 22 and is movable along the respective main chord 21 , 22. o a tagline trolley winch 35, 36 and a tagline trolley cable 41 , 42 driven by the tagline trolley winch, wherein the tagline trolley 31 , 32 is connected to the tagline trolley cable 41 , 42 such that a (un)winding of the tagline trolley winch provides a controlled displacement of the tagline trolley 31 , 32 along the main front chord 21 , 22. two horizontal tagline assemblies, each horizontal tagline assembly comprising a tagline winch 37, 38 and a tagline 33, 34 driven by the tagline winch, wherein the tagline 33, 34 - in use of the crane - extends from a respective tagline trolley 31 , 32 to the load connector 110.

[0049] The tagline system further comprises two vertical tagline assemblies, each vertical tagline assembly comprising a vertical tagline winch 53, 54 and a vertical tagline 51 , 52 driven by the vertical tagline winch.

[0050] The vertical taglines 51 , 52- in use of the crane - extends from an outer end of the boom 20 to the load connector 110.

[0051] The tagline system further comprises a tagline control system 200, wherein the tagline control system 200 is configured to: receive a hoisting signal Sh, e.g. from an operator, corresponding to the lifting or lowering of the suspended load 100 by means of the hoisting winch 18, receive signals Si,S2, S3, S4from the tagline trolley winches 35, 36 and the tagline winches 37, 38 corresponding to the unwound length of the tagline trolley cables 41 , 42 and taglines 33, 34 respectively, send a tagline control signal Ci,C2, C3, C4 to the tagline trolley winches 35, 36 and the tagline winches 37, 38 corresponding to a (un)winding speed of the tagline trolley winches 35, 36 and the tagline winches 37, 38.

[0052] The method comprises the steps of: the tagline control system 200 receiving a hoist signal Sh, e.g. from an operator, corresponding to a lifting or lowering of the suspended load 100, the tagline control system 200 receiving signals Si,S2, S3, S4 from each of the tagline trolley winches 35, 36 and each of the tagline winches 37, 38 corresponding to the unwound length of the tagline trolley cables 41 , 42 and the taglines 33, 34 respectively, the tagline control system 200 determining the required (un)winding speed of each of the tagline trolley winches 35, 36 and each of the taglines winches 37, 38 based on the hoist signal Sh, the length of the tagline trolley cables 41 , 42, the length of the taglines 33, 34, and the geometry of the boom, e.g. of the front main chords 21 , 22, the tagline control system 200 sending a tagline control signal Ci,C2, C3, C4 to each of the tagline trolley winches 35, 36 and each of the tagline winches 37, 38,

[0053] (un)winding the hoist winch 18 based on the hoist signal Sh and (un)winding each of the tagline trolley winches 35, 36 and each of the tagline winches 37, 38 based on the respective the control signal Ci,C2, C3, C4.

[0054] In an embodiment, the tagline trolley winches 35, 36 are set to have the trolleys 31 , 32 follow the load 100, e.g. the vertical orientation of the section of the taglines 33, 34 extending between the tagline trolley 31 , 32 and the load / load connector remains constant, this allows for an easier and more constant control of the load.

[0055] In the shown embodiment, the two front main chords 21 , 22 of the boom 20 are non-parallel with respect to each other.

[0056] In an embodiment, the tagline control system 200 is configured to receive tagline control signals Ss.Se, S7, Ss, e.g. from an operator, corresponding to an (un)winding of the tagline trolley winches 35, 36 and tagline winches 37, 38, wherein the method comprises the steps of:

[0057] - the tagline control system 200 determining the required (un)winding speed of each of the tagline trolley winches 35, 36 and each of the taglines winches 37, 38 based on the hoist signal Sh, the length of the tagline trolley cables 81,82, the length of the taglines S3, S4, the geometry of the front main chords, and on the received tagline control signals Ss.Se, S7, Ss.

[0058] In an embodiment, the tagline control system 200 determines the required (un)winding speed of each of the tagline trolley winches 35, 36 and each of the taglines winches 37, 38 solely based on the received tagline control signals Ss.Se, S7, Ss, e.g. a full manual control mode.

[0059] In an embodiment, the tagline control system 200 is configured to receive tagline control signals from an input device 300, e.g. one or more joysticks configured to be used by an operator, wherein based on the inputs provided to the input device a tagline control signal Ss.Se, S7, Ss corresponding to the (un)winding of the tagline trolley winches 35, 36 and / or tagline winches 37, 38 is send to the tagline control system 200, which then sends a control signal Ci,C2, C3, C4 to the tagline trolley winches 35, 36 and / or tagline winches 37, 38. In an embodiment, the tagline system 200 comprises tension sensors 210 which are configured to measure the tension of the taglines, wherein the control system is configured to receive signals ST from the tension sensors 210 corresponding to the tension in the taglines.

[0060] In an embodiment, the method comprises the step of keeping a certain, approximately, constant tension in the taglines during operation of the crane. This facilitates in keeping the load in a stable orientation and position. It is important to always have a certain tension in the taglines, otherwise the taglines cannot be used to control the load.

[0061] In an embodiment, the tagline control system is configured to unwind the tagline winches if the tension in the taglines goes over a pre-determined maximum tension, e.g. in case of a wind gust. This ensures that the tension in the taglines becomes too high and thereby damaging the crane.

[0062] In an embodiment, the tagline control system 200 is configured to receive signals Sg,S from the vertical tagline winches 53, 54 corresponding to the unwound length of the vertical taglines 51 , 52, and wherein the tagline control system 100 is configured to send control signals Cs, Ce to the vertical tagline winches 53, 54 corresponding to an (un)winding speed of the vertical tagline winches 53, 54.

[0063] The method comprises the steps of: the tagline control system 200 receiving signals Sg,S from each of the vertical tagline winches 53, 54 corresponding to the unwound length of the vertical tagline 51 , 52, the tagline control system 200 determining the required (un)winding speed of each of the vertical taglines winches 53, 54 based on the hoist signal Sh, the length of the tagline trolley cables Si,S2, the length of the taglines S3, S4, the length of the vertical taglines Sg,S , and the geometry of the front main chords, and optionally on the tagline control signals Ss.Se, S7, Ss, the tagline control system 200 sending a tagline control signal C5, Ce to each of the vertical tagline winches 53, 54,

[0064] (un)winding the tagline winches 53, 54 based on the respective the control signal C5, C6.

Claims

C L A I M S1. Method for controlling a load (100), e.g. a wind turbine component, suspended by a hoisting wire (19) of a crane (10), wherein the crane comprises: a base structure (11), e.g. adapted to be mounted on a vessel (1), a revolving structure (12) slewable on a slew bearing (13) about a vertical slew axis(14) relative to the base structure, a boom (20) which is at an inner end thereof pivotally connected to the revolving structure, wherein the boom can pivot about a horizontal pivot axis, wherein, preferably, the boom is embodied as a latticed hollow box structure comprising two front main chords (21 , 22) at a front side of the boom and two rear main chords at a rear side of the boom, a luffing device (15) for pivoting the boom about the horizontal pivot axis, wherein the luffing device comprises a luffing winch (16) and a variable length luffing system (17), a hoisting winch (18), a hoisting wire (19) driveable by the hoisting winch, and a load connector (110) suspended from the boom via the hoisting wire, wherein the load is connected to the load connector, wherein the crane further comprises a tagline system configured to control the suspended load, wherein the tagline system comprises: two horizontal tagline trolley assemblies each comprising: o a tagline trolley (31, 32) which travels along the boom, preferably the tagline trolley engages a respective one of the front main chords and is movable along the respective main chord, o a tagline trolley winch (35, 36) and a tagline trolley cable (41, 42) driven by the tagline trolley winch, wherein the tagline trolley is connected to the tagline trolley cable such that a (un)winding of the tagline trolley winch provides a controlled displacement of the tagline trolley along the boom, e.g. along the main front chord, two horizontal tagline assemblies, each horizontal tagline assembly comprising a tagline winch (37, 38) and a tagline (33, 34) driven by the tagline winch, wherein the tagline - in use of the crane - extends from a respective tagline trolley to the load and / or to the load connector, wherein the tagline system further comprises a tagline control system (200), wherein the tagline control system is configured to:receive a hoisting signal (Sh), e.g. from an operator, corresponding to the lifting or lowering of the suspended load by means of the hoisting winch, receive signals (Si,S2, S3, S4) from the tagline trolley winches and the tagline winches corresponding to the unwound length of the tagline trolley cables and taglines respectively, send a tagline control signal (Ci,C2, C3, C4) to the tagline trolley winches and the tagline winches corresponding to a (un)winding speed of the tagline trolley winches and the tagline winches, wherein the method comprises the steps of: the tagline control system receiving a hoist signal, e.g. from an operator, corresponding to a lifting or lowering of the suspended load, the tagline control system receiving signals from each of the tagline trolley winches and each of the tagline winches corresponding to the unwound length of the tagline trolley cables and the taglines respectively, the tagline control system determining the required (un)winding speed of each of the tagline trolley winches and each of the taglines winches based on the hoist signal, the length of the tagline trolley cables, the length of the taglines, and the geometry of the boom, e.g. of the front main chords, the tagline control system sending a tagline control signal to each of the tagline trolley winches and each of the tagline winches,(un)winding the hoist winch based on the hoist signal and (un)winding each of the tagline trolley winches and each of the tagline winches based on the respective the control signal.

2. Method according to claim 1, wherein the boom is embodied as a latticed hollow box structure comprising two front main chords at a front side of the boom and two rear main chords at a rear side of the boom, and wherein the tagline trolley engages a respective one of the front main chords and is movable along the respective main chord, e.g. wherein the two front main chords are non-parallel with respect to each other.

3. Method according to claim 1 or 2, wherein the tagline control system is configured to receive tagline control signals (Ss.Se, S7, Ss), e.g. from an operator, corresponding to an (un)winding of the tagline trolley winches and tagline winches, wherein the method comprises the steps of:- the tagline control system determining the required (un)winding speed of each of the tagline trolley winches and each of the taglines winches based on the hoist signal, the lengthof the tagline trolley cables, the length of the taglines, the geometry of the front main chords, and on the received tagline control signals.

4. Method according to any one or more of claims 1-3, wherein the tagline system comprises tension sensors which are configured to measure the tension of the taglines, wherein the control system is configured to receive signals from the tension sensors corresponding to the tension in the taglines.

5. Method according to claim 4, wherein the method comprises the step of keeping an approximately constant tension in the taglines during operation of the crane.

6. Method according to claim 4 or 5, wherein the tagline control system is configured to unwind the tagline winches if the tension in the taglines goes over a pre-determined maximum tension, e.g. in case of a wind gust.

7. Method according to any one or more of claim 1 - 6, wherein the tagline system further comprises: two vertical tagline assemblies, each vertical tagline assembly comprising a vertical tagline winch (53, 54) and a vertical tagline (51, 52) driven by the vertical tagline winch, wherein the vertical tagline- in use of the crane - extends from an outer end of the boom to the load and / or to the load connector, wherein the tagline control system is configured to receive signals from the vertical tagline winches corresponding to the unwound length of the vertical taglines, and wherein the tagline control system is configured to send control signals to the vertical tagline winches corresponding to an (un)winding speed of the vertical tagline winches, wherein the method comprises the steps of: the tagline control system receiving signals (Sg.S ) from each of the vertical tagline winches corresponding to the unwound length of the vertical tagline, the tagline control system determining the required (un)winding speed of each of the vertical taglines winches based on the hoist signal, the length of the tagline trolley cables, the length of the taglines, the length of the vertical taglines, and the geometry of the front main chords, the tagline control system sending a tagline control signal (Cs, Ce) to each of the vertical tagline winches,(un)winding the tagline winches based on the respective the control signal.

8. A crane (10) which comprises: a base structure (11), e.g. adapted to be mounted or mounted on a vessel (1), a revolving structure slewable (12) on a slew bearing (13) about a vertical slew axis (14) relative to the base structure, a boom (20) which is at the inner end thereof pivotally connected to the revolving structure, wherein the boom can pivot about a horizontal pivot axis, wherein, preferably, the boom is embodied as a latticed hollow box structure comprising two front main chords (21 , 22) at a front side of the boom and two rear main chords at a rear side of the boom, a luffing device (15) for pivoting the boom about the horizontal pivot axis, wherein the luffing device comprises a luffing winch (16) and a variable length luffing system (17), a hoisting winch (18), a hoisting wire (19) driveable by the hoisting winch, and a load connector (110) suspended from the boom via the hoisting wire, wherein a load is connectable to the load connector, wherein the crane further comprises a tagline system configured to control the suspended load, wherein the tagline system comprises: two horizontal tagline trolley assemblies each comprising: o a tagline trolley (31, 32) which travels along the boom, preferably the tagline trolley engages a respective one of the front main chords and is movable along the respective main chord, o a tagline trolley winch (35, 36) and a tagline trolley cable (41, 42) driven by the tagline trolley winch, wherein the tagline trolley is connected to the tagline trolley cable such that a (un)winding of the tagline trolley winch provides a controlled displacement of the tagline trolley along the boom, e.g. along the main front chord, two horizontal tagline assemblies, each horizontal tagline assembly comprising a tagline winch (37, 38) and a tagline (33, 34) driven by the tagline winch, wherein the tagline - in use of the crane - extends from a respective tagline trolley to the load and / or to the load connector, wherein the tagline system further comprises a tagline control system (200), wherein the tagline control system is configured to: receive a hoisting signal (Sh), e.g. from an operator, corresponding to the lifting or lowering of the suspended load by means of the hoisting winch,receive signals (Si,S2, S3, S4) from the tagline trolley winches and the tagline winches corresponding to the unwound length of the tagline trolley cables and taglines respectively, send a tagline control signal (Ci,C2, C3, C4) to the tagline trolley winches and the tagline winches corresponding to a (un)winding speed of the tagline trolley winches and the tagline winches, wherein the tagline control system is configured to, e.g. programmed to, perform a method which comprises the steps of: the tagline control system receiving a hoist signal, e.g. from an operator, corresponding to a lifting or lowering of the suspended load, the tagline control system receiving signals from each of the tagline trolley winches and each of the tagline winches corresponding to the unwound length of the tagline trolley cables and the taglines respectively, the tagline control system determining the required (un)winding speed of each of the tagline trolley winches and each of the taglines winches based on the hoist signal, the length of the tagline trolley cables, the length of the taglines, and the geometry of the boom, e.g. of the front main chords, the tagline control system sending a tagline control signal to each of the tagline trolley winches and each of the tagline winches,(un)winding the hoist winch based on the hoist signal and (un)winding each of the tagline trolley winches and each of the tagline winches based on the respective the control signal.

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