Watercraft with an electric propulsion motor

Abstract

The present invention relates to a watercraft (10). The watercraft (10) comprises: - a drive propeller (20) for driving the watercraft (10), - an electric drive motor (30), wherein the drive motor is operatively connected to the drive propeller (20) for driving the drive propeller (20), - an electronic motor control (80) for controlling the drive motor (30), wherein the electronic motor control (80) has a first operating mode, wherein the motor control (80) is configured in the first operating mode to operate the drive motor (30) in a speed-controlled, load-independent speed-controlled manner at a desired speed.The watercraft (10) has a rudder (40) or a device for pivoting the drive propeller (20), wherein the watercraft (10) has a sensor device, wherein the sensor device is designed to detect a pivot position of the rudder (40) or of the drive propeller (20) and / or a change in the pivot position of the rudder (40) or of the drive propeller (20), wherein the sensor device is designed to transmit a control signal to the engine control (80) depending on the pivot position and / or the temporal change in the pivot position in order to effect a change in the operating mode of the engine control (80).

Description

[0001] The present invention relates to a watercraft with an electric propulsion motor. The propulsion motor is preferably an inboard motor, thus a propulsion motor that is installed in a hull of the watercraft. Such an inboard motor is often also referred to as an inboard engine. However, the propulsion motor can also be an outboard motor. Outboard drives are among the most widely used propulsion systems for smaller boats. An outboard drive is a complete propulsion unit with an engine, propeller, and supporting systems, such as a gearbox or an electronic engine control unit. The outboard drive is usually mounted at the stern of the boat.

[0002] Conventional propulsion motors for watercraft are generally internal combustion engines. Such internal combustion engines generally exhibit a relatively high inertia in their response to changes in speed. Watercraft with electric propulsion motors are also known from the prior art. For example, JP 2019-69 744 A describes a watercraft with an electric propulsion motor, wherein the watercraft has a control unit that regulates the speed of the electric propulsion motor. If there is a difference between a target speed and a current speed, the speed of the motor is controlled accordingly. JP 2015-112 883 A discloses further prior art. EP 4 137 400 A1 discloses a watercraft having the features of the preamble of claim 1. EP 3 321 171 A1 discloses further prior art.

[0003] The object of the present invention is to improve a watercraft having the features of the preamble of claim 1 with regard to its handling when cornering. This object is achieved by a watercraft having the features of claim 1 and by the method according to claim 10. Advantageous further developments are the subject of the respective subclaims.

[0004] The watercraft according to the invention comprises: - a propulsion propeller to drive the vessel, - an electric drive motor, wherein the drive motor is operatively connected to the drive propeller to drive the drive propeller, - an electronic engine control for controlling the drive motor, wherein the electronic engine control has a first operating mode, wherein the engine control is configured in the first operating mode to operate the drive motor in a speed-controlled manner, in particular in a load-independent speed-controlled manner, at a desired speed.

[0005] Compared to the torque control usually provided with electric drive motors, i.e. torque-controlled electric drive motors, speed control has the advantage that speed losses when the load resistance / driving resistance increases are avoided. This can prevent a drop in speed when cornering, as occurs with a torque-controlled drive motor, and thus a drop in speed. Speed ​​control can improve driving dynamics when cornering. The speed is quickly adjusted and thus maintains the boat's speed even under heavy loads. Even when the watercraft is planing, speed-controlled operation of the electric drive motor, in particular load-independent speed-controlled operation, has proven advantageous in order to maintain stable planing even when driving resistance changes.When traveling on waves, a smooth planing motion in torque-controlled operation can only be guaranteed at a relatively high drive torque, which can result in operation at an inefficient operating point.

[0006] The drive motor is preferably an inboard motor, i.e. a drive motor that is located inside the hull of the watercraft, preferably permanently installed. The drive motor is preferably connected to the external drive propeller via a Z-drive. It is entirely conceivable for the engine control system to have an external module, whereby this external module controls the drive motor in the first operating mode and thus operates the drive motor with speed control. It is entirely conceivable for the engine control system to have an internal module, whereby this internal module controls the drive motor in a second operating mode, whereby the second operating mode is torque-controlled and thus operates the drive motor with torque control.

[0007] It is considered advantageous if the drive motor's motor shaft is operatively connected to the drive propeller without the need for a coupling. This makes the design of the drive motor particularly simple. Against this background, it is considered advantageous if the drive motor's motor shaft is mechanically connected directly and non-rotatably to the drive propeller. Preferably, the drive motor's motor shaft is operatively connected to the drive propeller without the need for a coupling.

[0008] It is considered particularly advantageous if the drive motor's shaft is operatively connected to the drive propeller without a coupling. This design has the advantage that the operative connection between the drive motor and the drive propeller can be designed particularly simply and robustly.

[0009] In a particularly preferred embodiment, it is provided that the motor shaft of the drive motor is mechanically connected directly and non-rotatably to the drive propeller.

[0010] In a particularly preferred embodiment, the watercraft is provided with a sensor for detecting the actual speed of the drive motor. It is entirely conceivable that the sensor for detecting the actual speed is a voltage sensor, whereby this voltage sensor detects an operating voltage of the electric drive motor, whereby the operating voltage of the electric drive motor is proportional to the speed of the drive motor and thus also proportional to the speed of the drive propeller. In an advantageous further development, the actual speed is detected via a position sensor. The position sensor can comprise a resolver or an encoder.

[0011] In this context, a propulsion propeller refers in particular to components suitable for propelling a watercraft by displacing water. Accordingly, the propulsion propeller is located in or under water during the operation of the watercraft. The propulsion propeller is, in particular, a ship's propeller.

[0012] It is considered particularly advantageous if the motor control has a second operating mode, wherein the motor control is configured in the second operating mode to operate the drive motor with a torque-controlled, speed-independent torque at a desired torque. Torque control is particularly easy to implement and is often already an integral component of electric drive motors or a control unit for controlling the drive motor. The control unit can, for example, be a component of an inverter. It is considered particularly advantageous if the second operating mode represents a normal mode of the motor control, so that the drive motor is operated with torque control during normal operation of the watercraft.

[0013] It is provided that the watercraft has a rudder or a device for pivoting the drive propeller, wherein the watercraft has a sensor device, wherein the sensor device is designed to detect a pivot position of the rudder or the drive propeller and / or a change in the pivot position of the rudder or the drive propeller, wherein the sensor device is designed to transmit a control signal to the engine control system depending on the pivot position and / or the temporal change in the pivot position in order to effect a change in the operating mode of the engine control system. This design has the advantage that the operating mode is activated depending on the pivot position or a change in the pivot position, for example a change from the second operating mode to the first operating mode. Different driving situations orChanges in the driving situation of watercraft generally occur when corresponding adjustments are made to the swivel position of the rudder or the drive propeller, for example, to execute or initiate a turn.

[0014] Especially when cornering, torque-controlled electric drives experience a drop in speed due to the increased drag during cornering. Such behavior is perceived by the driver as undynamic and thus negatively impacts the driving pleasure. Furthermore, the decrease in speed is difficult to assess, making it difficult for the driver to predict how the vessel will behave when cornering. This can lead to dangerous situations, especially when performing evasive maneuvers.

[0015] In a particularly preferred embodiment, it is provided that the sensor device has an evaluation device, wherein the evaluation device is designed to determine, on the basis of the pivot position and / or the temporal change in the pivot position, whether a curve is being traveled by the watercraft or whether a curve is being initiated, wherein upon determination of a curve or the initiation of a curve, the sensor device transmits a control signal to the engine control, wherein the engine control is set into the first operating mode by the control signal.

[0016] In order to maintain the most constant propulsion speed possible, even when cornering, it is considered particularly advantageous if the current actual speed of the drive motor is recorded, whereby this current actual speed forms the target speed for the speed control or the target speed for the speed control is dependent on the current actual speed. This design has the advantage that the speed when cornering is identical, or as identical as possible, to the current actual speed, i.e. the speed present when cornering is initiated. However, it is also entirely conceivable that the target speed is determined or calculated on the basis of the current actual speed, for example the target speed is increased by a certain factor compared to the current actual speed in order to improve driving dynamics when cornering.

[0017] In a particularly preferred embodiment, the watercraft is provided with an operating element, wherein the operating mode of the engine control can be manually selected by a driver of the watercraft by operating the operating element. This configuration enables the driver of the watercraft to actively change the operating mode in order to change the driving dynamics of the watercraft. The operating element can be a touchscreen, for example. It is also entirely conceivable for the operating element to be an element that is not permanently installed in the watercraft. The operating element can also be a smartphone, for example.

[0018] When starting and / or accelerating the watercraft, undesirable slip or undesirable excessive slip can occur, resulting in only a relatively small proportion of the propeller's drive torque actually being converted into propulsion. The remaining energy is then typically dissipated into heat and cavitation. This results in the electric drive motor operating inefficiently, as not all of its energy or power is converted into propulsion. Furthermore, the watercraft's optimal acceleration is not achieved. This problem can be at least partially compensated for by a speed control system.It is considered particularly advantageous if the engine control system, in the first operating mode, is configured to increase the actual speed to the requested target speed along a variable acceleration ramp stored in the engine control system during a starting or acceleration phase. The acceleration ramp depends on specific parameters of the vessel and / or the vessel's weight load. The vessel's draft could also be considered as a possible parameter.

[0019] The variable speed ramps can be calibrated or created by measuring the vessel and the engine for different weight conditions of the vessel, for example via (GPS measurements).

[0020] It is considered particularly advantageous if the engine control unit has an input device or if a communication connection with the engine control unit can be established using an input device, wherein the input device enables the input and transmission of data to the engine control unit, wherein the data relates to specific parameters of the watercraft and / or the current weight load of the watercraft and / or parameters influencing the weight load of the watercraft. This embodiment makes it possible to select or use the optimal acceleration ramp by entering the appropriate data for the specific parameters of the watercraft, in particular the current weight load of the watercraft. For example, it can be provided to enter the number of people on board the watercraft via the input device.The number of people on board directly influences the weight capacity of the watercraft and can therefore be taken into account when selecting the acceleration ramp to be used. Accordingly, it is considered particularly advantageous if the variable acceleration ramp is dependent on the number of people on board.

[0021] The one or more acceleration ramps can be created, for example, by increasing the actual speed along an initial acceleration ramp to the requested target speed during a start-up or acceleration phase, wherein a slip of the drive propeller is measured, wherein the initial acceleration ramp is varied such that the slip of the drive propeller is minimized or the slip of the drive propeller is within a predetermined tolerance band.

[0022] The following figures illustrate the invention in more detail using an exemplary embodiment, without being limited to this embodiment. They show: Fig. 1 a watercraft, namely an electric boat, in a side view, Fig. 2 the vessel in accordance with Fig. 1 in a top view while cornering, Fig. 3 the vessel in accordance with Fig. 1 during a gliding flight in a side view.

[0023] The Fig. 1 to 3 each show a watercraft 10 according to the invention, wherein this watercraft 10 is embodied as an electric boat, specifically as an electric sports boat. The watercraft 10 comprises a drive propeller 20 for driving the watercraft 10. The watercraft 10 further comprises an electric drive motor 30, wherein the drive motor 30 is operatively connected to the drive propeller 20 for driving the drive propeller 20. The watercraft 10 further comprises a rudder 40, wherein the rudder 40 can be changed with respect to its pivot position via a steering wheel 50 by a driver of the watercraft 10 for steering the watercraft 10. The pivot position of the rudder 40 is changed using a servomotor 60, which is operatively connected to the rudder 40. The servomotor 60 is controlled via the steering wheel 50.

[0024] The watercraft 10 includes a high-voltage battery 70, which can be, for example, a lithium-ion battery. The high-voltage battery 70 serves to supply the electric drive motor 30 with electrical energy.

[0025] The watercraft 10 further comprises an electronic engine control 80 for controlling the drive motor 30. The electronic engine control 80 has a first operating mode, wherein the engine control 80 is configured in the first operating mode to operate the drive motor 30 at a target speed, independent of the load, with speed control. In addition to the first operating mode, the engine control 80 also has a second operating mode, wherein the engine control 80 is configured in the second operating mode to operate the drive motor 30 at a target torque, independent of the speed, with torque control. During normal operation of the watercraft 10, the engine control 80 is operated in the second operating mode, so that the drive motor 30 is torque-controlled. Such torque control is particularly advantageous for journeys with relatively constant driving resistances and is perceived as pleasant by a driver of the watercraft 10.However, if there is a change in the driving resistance, torque control usually results in a decrease in the speed of the watercraft 10. Such an increase in driving resistance occurs, for example, when cornering, as in the . Fig. 2. The cornering or movement of the watercraft 10 is indicated by the arrow 100. In order to avoid a decrease in speed when cornering, the watercraft 10 is provided with a sensor device for detecting a pivot position of the rudder 40 relative to an axis of the watercraft 10, for example relative to a longitudinal axis L of the watercraft 10. The sensor device is configured to transmit a control signal to the engine control 80 depending on the pivot position and / or the temporal change in the pivot position of the rudder 40. The sensor device can, for example, be a sensor device that monitors the steering wheel 50, since a change in the position of the steering wheel 50 is directly related to the pivot position of the rudder 40.The sensor device has an evaluation device, wherein the evaluation device is configured to determine, based on the pivot position and / or the temporal change in the pivot position of the rudder 40, whether the watercraft 10 is cornering or is about to be initiated. If the evaluation device detects cornering or the initiation of cornering, the sensor device transmits a control signal to the engine control 80, whereby the engine control 80 is placed in the first operating mode. In addition, upon detection of cornering and / or the initiation of cornering, the current actual speed of the drive motor 30 is recorded, wherein this current actual speed forms the desired speed for the speed control. This ensures that the watercraft 10 does not lose speed or only loses speed slightly when cornering.

[0026] The watercraft 10 further comprises an operating element 90, wherein this operating element 90 enables the operator of the watercraft 10 to manually select the operating mode of the engine control 80 by a corresponding operating action on the operating element 90. This can be advantageous, for example, when the watercraft 10 is in planing mode, as is the case with the Fig. 3 driving situation is the case. How to Fig.3, a certain amount of swell is present, and the driving resistance changes periodically due to the swell. With torque control, thus with operation of the motor control 80 in the second operating mode, the swell would cause the speed of the drive motor 30 and thus of the drive propeller 20 to also change periodically. This leads, on the one hand, to higher energy consumption and, on the other hand, to a constant change in the speed of the watercraft 20. By changing the operating mode to the first operating mode in such a situation, the speed of the drive motor 30 is used as a controlled variable. For example, the current ACTUAL speed present during the change can be used as the TARGET speed for the speed control. As a result, the watercraft 10 travels at a more constant speed than would be the case with torque control, even with periodically changing driving resistance.

Claims

[1] Vessel (10) comprising: - a drive propeller (20) for driving the watercraft (10), - an electric drive motor (30), wherein the drive motor (30) is operatively connected to the drive propeller (20) for driving the drive propeller (20), - an electronic motor control (80) for controlling the drive motor (30), wherein the electronic motor control (80) has a first operating mode, wherein the motor control (80) is configured in the first operating mode to operate the drive motor (30) in a speed-controlled manner at a desired speed, characterized byin that the watercraft (10) has a rudder (40) or a device for pivoting the drive propeller (20), wherein the watercraft (10) has a sensor device, wherein the sensor device is designed to detect a pivot position of the rudder (40) or of the drive propeller (20) and / or a change in the pivot position of the rudder (40) or of the drive propeller (20), wherein the sensor device is designed to transmit a control signal to the engine control (80) depending on the pivot position and / or the temporal change in the pivot position in order to effect a change in the operating mode of the engine control (80). [2] Watercraft (10) according to claim 1, wherein a motor shaft of the drive motor (30) is operatively connected to the drive propeller (20) without a coupling. [3] Watercraft (10) according to one of claims 1 to 2, wherein the watercraft (10) has a sensor for detecting an actual speed of the drive motor (30). [4] Watercraft (10) according to one of claims 1 to 3, wherein the engine control (80) has a second operating mode, wherein the engine control (80) is configured in the second operating mode to operate the drive motor (30) in a torque-controlled manner with a desired torque, independent of the speed. [5] Watercraft (10) according to one of claims 1 to 4, wherein the sensor device has an evaluation device, wherein the evaluation device is designed to determine on the basis of the pivot position and / or the temporal change in the pivot position whether a cornering of the watercraft (10) is present or is initiated, wherein upon determining a cornering or the initiation of a cornering, the sensor device transmits a control signal to the engine control (80), wherein the engine control (80) is set into the first operating mode by the control signal. [6] Watercraft (10) according to claim 5, wherein the current actual speed of the drive motor (30) is detected, wherein this current actual speed forms the desired speed for the speed control or the desired speed for the speed control is dependent on the current actual speed. [7] Watercraft (10) according to one of claims 1 to 6, wherein the watercraft (10) has an operating element (90), wherein the operating mode of the engine control (80) can be manually selected by a driver of the watercraft (10) by an operating action on the operating element (90). [8] Watercraft (10) according to one of claims 1 to 7, wherein the engine control (80) is configured in the first operating mode to increase the actual speed to the requested target speed along a variable acceleration ramp stored in the engine control (80) during a starting or acceleration phase, wherein the acceleration ramp is dependent on specific parameters of the watercraft (10) and / or a weight load of the watercraft (10). [9] Watercraft (10) according to claim 8, wherein the engine control (80) has an input device or a communication connection with the engine control (80) can be established with an input device, wherein the input device enables the input and transmission of data to the engine control (80), wherein the data relate to specific parameters of the watercraft (10) and / or the existing weight load of the watercraft (10) and / or parameters influencing the weight load of the watercraft (10). [10] Method for creating one or more acceleration ramps for the engine control (80) of a watercraft (10) according to claim 8 or 9, wherein during a starting or acceleration phase the actual speed is increased along an initial acceleration ramp to the requested desired speed, wherein a slip of the drive propeller (20) is measured, wherein the initial acceleration ramp is varied such that the slip of the drive propeller (20) is minimized or the slip of the drive propeller (20) is within a predetermined tolerance band.

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