KR100700242B1 - Ship propulsion system comprising a control that is adapted with regard to dynamics - Google Patents

Abstract

The present invention relates to a ship propulsion system, which consists of a ship propulsion system (5) and an electric propulsion system (3, 4) powered from an electrical system and equipped with an actuating controller (6) for a propeller motor (3). . The rotational speed of the propeller motor 3 is set in advance by the multi-order controller 2 having command variables issued by the control lever 1. Filter means are provided to suppress operational damage of the vessel due to the high dynamics of the propulsion systems 3, 4.

Description

SHIP PROPULSION SYSTEM COMPRISING A CONTROL THAT IS ADAPTED WITH REGARD TO DYNAMICS

Propulsion systems for ship propellers with electric propeller motors use a rotary speed regulator for closed loop control. The rotation speed nominal value is preset using the control lever on the bridge. Upstream of the regulator input side, the rotational speed nominal value (reference variable) is compared with the rotational speed value at which time a control error is determined from the comparison and fed to the regulator. The output signal from the regulator is a control variable that passes through the actuating device connecting the propeller motor to the power source.

When synchronous machines are used for propulsion, the actuating device is in the form of a frequency changer / converter, which uses the generator voltage from the diesel generator system to generate a suitable polyphase variable frequency supply voltage. The converter circuit is designed to respond similarly to the response from a direct current controller controlled by a direct current controller with the interconnection of the converter and the synchronous machine. The signal passing through the control input side of the DC controller controls the current applied by the DC motor. In the same way, the control signal from the regulator controls the current used to operate the synchronous machine. In the same way, asynchronous machines can also be powered and used to propel a ship.

This type of propulsion system has been known to be relatively powerful. That is, such a propulsion system can adjust a small number of rotational speed fluctuations within one revolution of the propeller.

The reason for the rotational speed variation and / or the angular velocity change is due to the propeller's movement in the water passing through the hull during the ship's voyage and its three-dimensional non-uniform velocity profile. During the propeller blade movement, somewhere the propeller blades move through a skeg or propeller-shaft stay on the ship's hull, while water at a different flow rate at the stop of the propeller blades moves to the propeller blades. Crash.

From a hydrodynamic point of view, the change in the load on the propeller of a ship over time can be explained by the navigation route. This change in load due to the skeg or propeller shaft stay on the ship hull is once again evidence that the propeller wake field is non-uniform, which also causes a change in the angle that proceeds during the rotation of the propeller blades.

This means that the torque fluctuates periodically by a ship propeller with varying angular velocities, the angular velocities being controlled by a rotational speed regulator or a lower current regulator, so that the ship screw matches as accurately as possible with a predetermined nominal rotational speed value. Maintain the speed of rotation. The frequency of the torque fluctuations corresponds to the shaft rotation speed multiplied by the number of blades on the propeller. Torque fluctuations are transmitted from the propulsion motor to the anchor and to the ship's hull. Torque reactions also occur in diesel generator systems. As a result, part of the ship structure vibrates at the fundamental frequency of this pulsating torque, and as a result of the mechanical properties, the resonance of the ship hull is not negligible at the relevant frequency. This vibration not only annoys everything on the ship, but also creates a significant load on the entire structure of the ship and its cargo and should be avoided.

In the past, attempts have been made to calculate the weakness against such vibrations using the so-called Finite Element Method and to reinforce the calculated critical area using the tonnage of steel. This method is expensive on the one hand and on the other hand increases fuel consumption while reducing the maximum allowable cargo weight and the cargo area of the vessel. However, even if it is possible to reduce the influence of vibration generated by propulsion, which destroys the material, the cause has not been eliminated.

Closed loop speed control, which maintains the speed of the ship propellers at a predetermined nominal speed value as accurately as possible, has another adverse effect.

Although the nonuniformity of the track sufficiently reflects the variation of the propeller's forward angle, the propeller's cavitation safety margin is reduced. The reason for this is that the propeller's operating point may be close to or far exceed the cavitation limit. In particular, the operating point of the propeller in the skeg or propeller shaft stay area on the ship hull can reach or exceed the cavitation limit and thus the initial cavitation, which can cause significant damage to the ship, in particular the propeller. Cavitation also results in unacceptable pressure fluctuations and noise that significantly reduce the usefulness and comfort of passenger ships, survey ships, and military vessels in particular.
The rotational speed of the ship propeller driven by the electric motor can be adjusted very quickly. Rapid adjustment of the speed of rotation results in particular on cavitation on the propeller blades. In this case, the rate of adjustment of the rotational speed is dependent on the speed of the ship's movement, ie the inflow rate at which water strikes the propeller.

For this reason, there is provided a ramp-up transmitter located between the control lever and the standard value input regulator in terms of control engineering.

As the actual propeller speed of a ship propeller increases, the dynamic response of the propeller also changes significantly. Since a group of curves for a propeller (related to a change from a run curve to a free drive curve) follow a square-law, the maximum permissible dynamic response of a ship propeller is proportional to the increase in the actual speed of rotation. Decreases more than

In the case of ship propeller propulsion devices known from the prior art, the ramp-up time controlled by the ramp-up transmitter is such that the rotational speed of the propulsion motor for the propeller is maintained to maintain an excessive rotational speed within the maximum permissible area of the propeller curve. Increases with increase.

In addition, with regard to power requirements, the electric propulsion system must also take into account generator excitation. The time response of an electric propulsion system is slower than the possible dynamic response of an electric machine for ship propellers.

In consideration of these two limit conditions, the lamp-up transmitter according to the prior art is designed as follows.

The propeller motor starting at zero rotation speed is first of all accelerated without any limitation, ie optimally. The power dissipated by the propeller rises faster during ramp-up with a constant ramp-up time, finally reaching the current limit of the speed regulator to prevent overloading the diesel generator system. At the end of the first stage of the ramp-up transmitter it is changed to a different ramp-up time. The acceleration power available for electric propulsion actually decreases to zero. This results in sudden changes in power consumption from diesel generator systems that are not necessary but must be adjusted, and also cause frequency and / or voltage fluctuations in the on-board power supply network.

At least in the first phase of the ramp-up time, the propulsion device draws power from the diesel generator system, which in some cases interrupts the power supply to the rest of the on-board power supply network.

In the change from the first ramp-up stage for ship acceleration to the second ramp-up stage, this results in the disadvantage of accelerating only a very small range within a certain speed range.

In the propulsion system as described above, the current limit of the electric machine for the propeller occurs at a rotational torque of approximately 30% above each ship propeller curve. This area between the current upper limit of the electric propeller and the calculated ship propulsion curve is necessary to provide for the rough seawater situation and / or ship coordination in addition to the acceleration torque required for the processes involved in the acceleration of the ship.

The ramp-up transmitter, which has been controlled at the stages of propellers for ship propellers, has never been possible for the electric machine driving the propellers to produce the prescribed acceleration torque during the acceleration process. In fact, over a wide range of speeds, the ramp-up transmitter only allows each current limit at that time. The reason for this is that the acceleration time for the ship corresponds to several multiples of the ramp-up transmitter.

As already mentioned above, diesel generator systems have power responsiveness over time that can change later than the power consumption of the electrical machine for ship propellers. Thus, in addition to the limitations arising from the propeller curves, the limitations due to the maximum dynamic response of the generator system need to be taken into account.

When designing diesel engines for marine diesel generator systems, the requirements of the International Classification Council (IACS) require that load responsiveness be taken into account. The three-stage load gradation associated with this specification requirement has a significant impact on the dynamic response of propulsion systems for ship propellers in current diesel engines with high boost levels. Another major requirement is that due to inadequate maintenance and the use of significantly lower bunker oils, known figures can no longer be solved at present, especially within the upper power limits. Therefore, in terms of cost, the maximum possible dynamic response for power dissipation on the diesel engine's shaft is reduced during long term sailing of the vessel.

Another time change in power release from diesel engines not specified by IACS or any other binding body is the diesel engine's heat load capability. From zero output to rated output at operating temperature, or from rated output to zero output, the change in the flexible load of the diesel engine can only be carried out within a minimum time depending on the physical size of each diesel engine. These times vary significantly as a function of physical size.

The time profile should not be exceeded in several places. The reason for this is that it causes damage to the diesel engine.

The minimum time described above may be 10 to 20 seconds for a small diesel engine and 120 seconds or less for a large engine.

The converter / frequency changer connected between the diesel generator system and the electric machine for the ship propeller requires a control wattless component. The control reactive component is load dependent. Examples of such converters / frequency converters are converters such as intermediate current circuit converters, direct converters and direct current machines.

The reactive component is supplied from a synchronous generator of the diesel generator system. The rate of time change of the load-dependent reactive component for the converter described above with respect to the control reactive component may vary 15 to 25 times faster than the thermal voltage of the synchronous generator, which the generator system cannot follow. In particular, time is needed to reduce the excitation field for synchronous generators.

If the dynamic limit of the diesel engine is exceeded when the ship propeller is driven, the rotational speed of the engine will fluctuate to unacceptably vary the frequency of the on-board power supply network supplied from the diesel generator system. In addition, it is not possible to rule out damage to the diesel engine when control of the closed loop rotational speed for the generator system is to maintain or maintain the frequency of the on-board power supply network within an acceptable range while ignoring the dynamic limits. . If the dynamic limit of a synchronous generator is exceeded, the voltage on the on-board power supply network will fluctuate significantly outside the tolerance range.

According to the prior art, the rotation in the course of a prolonged attempt to satisfactorily satisfy the interaction between the electric machine for ship propellers and the diesel generator system without any unacceptable frequency or voltage fluctuations occurring in the on-board power supply network. Experiments based on multi-step and continuous changes to ramp-up times of velocity nominal and / or current nominal have already been performed. In this case only, it was often possible to achieve optimization at some operating point. There was no consistent relationship between the ability to control closed-loop control for electric propellers for ship propellers and the dynamic effects on diesel generator systems in on-board power supply networks. The time profile for the reduction in load on diesel generator systems is not much considered and rarely adjusted for closed-loop control for propulsion systems for ship propellers.

In view of this background, it is an object of the present invention to provide a marine propulsion system for a ship which has an electrical on-board power supply network and which does not result in reduced comfort and / or any adverse effects on ship operation.

In particular, one of these aims is to be able to tune the dynamic responsiveness of the ship propulsion system to the various types of limiting situations described above.

According to the invention, this object is achieved by a marine propulsion system having the configuration of the features of claim 1.

The reduction in comfort may be expressed in the form of vibrations and / or flashing lights of the ship structure. The device according to the invention ensures that the on-board power supply network voltage and / or its frequency does not fluctuate beyond an acceptable degree, regardless of the speed at which the control lever and / or rudder angle is adjusted.

Thus, if the control lever is reset to zero too quickly, the load will be removed from the generator system faster than it can reduce the excitation of the synchronous machine, causing fluctuations in the on-board power supply network voltage. . Conversely, fluctuations may occur when the control lever moves very quickly in the direction of high motor power. In general, the frequency drops in this case because the diesel engine does not accelerate fast enough.

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The rudder movement has a similar effect on the generator system and / or on-board power supply network. As the rudder is deflected, the load on the propeller increases while the load on the propeller decreases when the rudder is moved to the null position.

An excessively fast acceleration process in the propeller can cause significant noise when acceleration causes cavitation in the propeller of the ship.

The connection of noise from the ship's hull and propellers underwater is seen as environmental pollution that is spread over a wide area and can significantly limit the use of ships in protected areas such as the Arctic and Antarctic. By means of the present invention, the above-mentioned reduction in noise emissions enables travel in areas of travel where the passenger vessel is financially of particular interest and in the area of a surviving animal safeguard against dangerous noise and pressure fluctuations. .

In order to counter the vibration generated by the change of torque while the ship's propeller is moving underwater, the filter means has a first filter means which is set to suppress the amplitude variation of the signal at the control input on the actuating device. Torque fluctuations cause a change in the angular velocity of the propeller shaft, which results in a ripple corresponding to the signal provided from the rotational speed transmitter. In the absence of the present invention, the ripple is reflected directly in the control deviation and causes a current for the propeller motor, so that the drive torque varies with the control deviation. The first filter means filters this ripple, i.e. the propulsion system provides the property to make the rotational speed smooth when the propeller blades run at high flow resistance, and the rotational speed is "difficulty to disturb movement". impeding movement ”disappears and can be resumed.

The filter means used for this purpose can amplify and filter the signal change passing only when the signal change exceeds a certain level. Such a filter may, for example, be in the form of a diode characteristic. Another specification is to use a frequency filter that acts as a low pass filter to filter the ripple, which is superimposed on the control deviation.

The frequency filter means may be designed such that the cutoff frequency is changed in accordance with the rotational speed of the propeller shaft or the initial voltage is varied in accordance with the basic or equivalent value of the input variable. This ensures that adequate dynamic response is provided for all rotational speed ranges without suppression of ripple through the operating device in the range of ripples or other rotational speeds that have no effect on the closed loop control dynamic response.

The first filter means can be arranged in the signal path of a signal with a control deviation between the regulator input and the rotational speed sensor, or can be arranged at the regulator output between the controller and the control input of the operating device.

If the filter means are in the form of an amplifying filter, the filter means are preferably located in the signal path for control deviation.

The closed loop control device preferably has a PI control response.

The closed loop control device may be configured in an analog closed loop control device or in a conventional manner of operating it digitally.

In the case of a PI regulator, certain filter characteristics are achieved by feeding back the output signal from the closed loop control device to the input in antiphase.

The actuating device for the propeller motor itself is again in the form of a regulator. The control signal for the actuating device in this case preferably has a significant current nominal value, ie the current is controlled and output from the actuating device to the propeller motor so that the torque delivered by the propeller motor is regulated. This open loop control is possible when the propeller motor is in the form of a synchronous machine and the actuator is in the form of a frequency converter or converter. Circuits suitable for this purpose are known in the art.

If feedback is used to filter the ripple, the feedback is preferably set to cause a steady-state control error of approximately 0.2 to approximately 3% at rated load. If this control error has a disturbing effect, it can be compensated using a properly selected nominal value. Nominal value compensation can be performed as a function of the estimate load.

In order to suppress cavitation on the propeller of the ship resulting from excessively fast acceleration, the filter means preferably have a second filter means, which is in the form of controlled ramp-up transmitters. The ramp-up transmitter is used to match the rate of change of the rotational speed of the propeller shaft to the maximum permissible level.

For this purpose, the second filter means, including the characteristic value, makes it possible to gradually lower the rate of rise of the nominal value signal reached from the control lever as a function of the rotational speed of the propeller motor. For this purpose, the second filter means can be arranged between the input of the closed loop control device and the control lever. Here, it includes a Peruvian control device, an operating device, and a ship propeller without adversely affecting the control response.

The property of the second filter means is continuous and in some ways it does not have discontinuities. There is no need to relax the mathematical dimension, but it can approximate the shape of a polygon. The only essential feature is that transitions do not have discontinuities within the polygon. The characteristic may be a square-law characteristic with an offset.

In order to allow the vessel to still be able to move well even in the low speed range, at least the ramp-up time is designed with a constant and short characteristic in the low rotational speed range, and is designed to rise only finely according to the rotational speed of the propeller. Thus, the propulsion system is effectively "attached" to the control lever directly.

In the high rotational speed range starting at a rated rotational speed of approximately 25% to 45%, the ramp-up time increases with or faster than the rotational speed of the propeller motor. As a result, the possible angular acceleration reduces the rotational speed of the high ship propeller regardless of the rate at which the control lever is moved.

For example, in the upper rotational speed range starting at half the rated rotational speed, the rate at which the propeller motor's rotational speed can be reduced is much more limited, i.e. the ramp-up time is much faster than the rotational speed range below. Increase.

However, the propeller motor is rotated so that the rate at which the propeller motor's rotational speed increases after a short ramp-up time increases with the square law and then gradually decreases by adding an offset to the square root function is increased. You can also control the speed.

The second filter means may be in digital form using a microprocessor or may be designed to operate in analog form.

As mentioned earlier in the introduction, the reduction occurs naturally when the on-board power supply network voltage fluctuates very heavily because the generator system cannot follow sufficiently with changes in the power requirements for ship propulsion. Excitation of a synchronous machine and, in particular, reduction in excitation of a synchronous machine requires time. If the power consumption by ship propulsion changes faster than can occur here for excitation / decrement, the on-board power network voltage is out of tolerance band, which is not necessary for the installation connected to the on-board power supply network. Overload or overload. Diesel drive for a generator cannot follow both quickly enough, which can cause damage to the diesel engine.

In order to eliminate the adverse effects resulting from this, the filter means may have a third filter means, which limits the rate of change of power consumption by the propeller motor, so that the on-board power supply network system can obtain the correct value without any problem. Can be followed.

The third filter means may again be arranged in the signal path of the nominal value signal, ie between the regulator and the control lever, downstream of the closed loop control device or within the actuating device itself. Downstream from the regulator or downstream from the subtraction point is characterized by a slow state change due to a change in propeller load. This change in propeller load occurs when the rudder moves or when the switch is turned off or when the propellers of a multiple shaft system are throttling down.

The third filter means is preferably embodied in digital form on the basis of a microprocessor.
The third filter means can also be of a typical design and can be operated in analog form.

The third filter means can be designed to limit the rate of change of the value which differs from the value used when the control lever moves in the direction of the higher power consumption, when the control lever moves in the direction of the lower power value.

The limit on the rate of change decreases at least in the upper power range or in the rotational speed range of the propeller motor.

The rate of change allowed by the third filter means may depend on the number of generators supplied to the on-board power supply network. Another affected variable may be the operating state of the system, ie the system is already warm up or warming up, which is dependent on the overall operating time. Thus, another influenced variable is the load of the generator system, ie the load of the diesel engine is low, medium or upper power range.

In order to maintain the ship's controllable condition and to avoid the control vibration due to the limit of the change rate, the third filter means does not affect the change rate when the signal of the control input of the operating device changes. The third filter means may be configured to provide a window within a range that does not. Such a window is particularly preferred when the third filter means is located in the signal path between the closed loop control device and the actuating device. If the third filter means is located between the control lever and the nominal value input of the closed loop control device, this window is somewhat unnecessary.

In addition, further embodiments of the invention are the subject matter of the dependent claims. In this case, the combination of features not reflected by the exemplary embodiment will be within the protection scope.

The patent claims refer to "ship propellers" and "propeller motors", which are not limited to the propellers of a single motor and a single ship, and that the propellers of multiple motors or ships are coupled to each other or It will be apparent to those skilled in the art that they can be controlled separately. The present invention is also equally relevant to surface vessels and underwater vessels.

1 is a block diagram of a ship propulsion system with a first filter means for reducing vibration of a hull by the operation of a propeller in water;

2 is a detailed block diagram of the closed loop control device shown in FIG.

 3 is a diagram illustrating a transmission response of an amplitude filter.

4 is a block diagram of a ship propulsion system with a second filter means for matching the kinetic response to the kinetic response of the ship's propeller;

5 is a diagram showing the transmission characteristics of the second filter means,

Figure 6 is a view showing a profile of the acceleration of the ship with respect to the ship equipped with the propulsion system according to the present invention,

7 is a block diagram of a propulsion system of a ship with a third filter means for matching the kinetic response of the propeller motor to the kinetic response of the generator system, FIG.

8 is a view showing the characteristics of the third filter means,

9 shows a profile of the start time and end time of a nominal current value for different numbers of supply generators,

10 shows a profile of a window for a third filter means which is not limited in change rate and related to a continuous value,

11 shows a profile of a window as a function of the number of activated generators.

1 shows a block diagram of an electric ship propulsion system. The block diagram illustrates only some of the important aspects of the present invention. Of course, the detailed circuit diagram of the ship propulsion system is considerably more complicated than this, but this is less valuable than merely showing all of the concepts of the present invention in detail and will be more difficult to understand.

The ship propulsion device comprises a control lever 1 arranged on the bridge, a closed loop control device 2, a propeller motor 3 for driving the propeller of the ship, and a schematic on-board power supply network ( 5) and an actuating device 6, the propeller motor 3 is connected to the on-board power supply network 5 via the actuating device 6. In this description, the term control lever is used to refer to any device, such as an automatic system, through which the speed of movement is preset to a high degree of control, i.e. "cruise control" for a ship. Used to express.

The control lever 1 supplies, as a reference variable, an electrical signal corresponding to the rotational speed of the propeller 4 of the ship to the nominal value input 8 of the closed loop control device 2 via the connection line 7. The closed loop control device 2 comprises a PI regulator 10 as well as an addition node 9, the output 11 of the PI regulator 10 being connected to the input 12 of the actuating device 6.

The closed loop control device 6 receives the actual signal value via the line 13 connected to the rotational speed sensor 14. The rotational speed sensor 14 consists of a digitally operated rotational speed transmitter 15 and a digital / analog converter 16 and is equipped with a rotational direction checker.

The rotational speed transmitter 15 is connected to the propeller shaft 17, which operates on the propeller motor 3 and rotates together since the ship's propeller 4 is installed on the shaft. The digital-to-analog converter 16 uses two phase shifted periodic digital signals from the rotational speed transmitter 15 to generate a signal proportional to the rotational speed and a mathematical signal in a known manner. Passes through line 13. This signal proportional to the rotational speed of the propeller 4 of the ship is compared with the signal from the control lever 1 at the addition node 9 of the closed loop control device 2.

Alternatively, the rotational speed sensor 14 may be an indirect measuring system. The rotational speed is sensed using the time profile of the current and the voltage, preferably at the connection line 19 to the actuating device 6 or the propeller motor.

The deviation obtained from the rotational speed is processed according to its characteristics in the PI regulator 10. The control response of the PI regulator is known and detailed description is omitted here.

The actuating device 6 is itself configured in the form of a regulator, for example a three-phase, polyphase on-board power supply network 5 and a bridge circuit connected in series between the propeller motor 3. It includes a controller 18 consisting of GTOs connected to the.

The propeller motor 3 is, for example, a synchronous machine, and the controller 18 is controlled to receive a suitable polyphase variable frequency alternating current power supply. The current sensor 21 is located in the line 19 between the controller 18 and the propeller motor 3 and is connected to the converter circuit 23 via the line 22. The current sensor 21 may be similarly arranged on the input side of the controller 18.

The converter circuit 23 generates a direct current signal from the alternating current signal sensed by the current sensor 21, which direct current root mean square value of the current flowing through the propeller motor 3, for example. Corresponds to). Accordingly, the converter circuit 23 sends a DC signal from the output unit 24 side and inputs it to the addition node 26 through the line 25. At the addition node 26, the signal proportional to the current from the current sensor 21 is compared with the output signal from the closed loop control device 2, and for this reason the other input of the addition point 26 is the input of the operating device ( 12). The deviation obtained between the current nominal value and the actual current value in this way flows through line 27 to another PI regulator 28, where the output signal of the PI regulator 28 is passed through line 29 to the drive circuit 31. Drive circuit 31 uses the output signal of the PI regulator to generate a control signal in the correct phase for the controller 18, the controller 18 being a multipole line 32. It is connected to the drive circuit through.

The operating device 6 in the case shown forms a converter. The propeller motor may be an asynchronous machine instead of a synchronous machine. Similarly, a direct current machine for supplying alternating current can be used.

The flow field of water flowing past the ship's propeller 4 is three-dimensionally different. The non-uniform flow distribution prevents the ship propeller 4 from always experiencing the same resistance torque during a complete one turn underwater. As the propeller blades enter any flow region, the blades encounter increased resistance. This three-dimensionally different resistance results in a change in torque when the propulsion shaft 17 is driven at a exactly constant rotational speed.

The constant shaft rotational speed causes the torque in the opposite direction to be produced in the propeller motor 3, which is transmitted to the ship structure. When the propeller blades come back out of the region of high flow resistance, the torque drops until the next propeller blade enters this flow region. Thus, the torque exerted by the propeller motor 3 changes periodically at a frequency equal to the product of the shaft rotational speed and the number of propeller blades.

Torque fluctation causes fluctuations in angular velocity and is detected by the rotational speed sensor 14 as angular velocity changes. The closed loop control device 2 attempts to adjust the rotational speed fluctuations in order to drive the propeller shaft 17 at a constant rotational speed. This causes considerable vibration in the hull of the ship.

The signal passing through the control input 12 of the actuating device 6 is composed of a direct current component, assuming no other measurements are taken, on which the ripple corresponding to the torque variation is superimposed.

According to the present invention, the closed loop control device is provided with first filter means for suppressing the above-mentioned ripple.

At the moment when the signal reaching the control input 12 has no ripple, the propeller motor 3 can drive the propeller 4 of the ship with a constant torque. The angular velocity of the propeller shaft 17 should be varied periodically corresponding to the "instantaneous resistance to movement" of the ship propeller 4 in water. For this purpose, the propeller motor 3 is largely free of periodic torque fluctuations that stimulate the ship structure to vibrate.

2 shows one specification for the execution of the first filter means. The regulator 10 comprises a proportional regulator 33 at the input side, which has an input side connected to the addition point 9 and an output side connected to the input of an integral regulator 34. The output of the integrating regulator 34 is connected to the input of the addition point 35 having another input connected to the output of the proportional regulator 33. The output of the addition point 35 forms the output of the regulator 10, which is connected to the connection line 11. Feedback resistor 36 is drawn from line 11 to the input of regulator 33, which feeds the output signal back to the input in reverse phase.

The regulator designed in this way has a low-pass / amplification response which, as a whole, can reduce ripple due to torque fluctuations at least from the propeller 4 of the ship.                 

Feedback resistor 36 changes the overall gain. If any error occurs between the rotational speed actual value (n) and the rotational speed nominal value (n ^* ), the changed rotational speed nominal value (n ^* ) is defined by the operating device 6 to produce the opposite torque. When generating the current nominal value I ^* , it is substantially reduced by the value of n _R = R × I ^* .

As a result, the n to the operating unit 6 is appropriately reduced rotational speed nominal value (n * _R -n) to try to control their own, and thus the propeller motor (3) to the n ^* _R -n from n ^* By reducing, it provides an opportunity to release flywheel energy from propulsion operations, including propeller motor 3, ship propeller 4 and propeller shaft 5. During processing, the closed-loop control device (2) includes a motor rotational speed (n) the rotational speed nominal value decreased by the decrease (n * _R -n) are substantially comparable, and almost no need to perform as a result of any operation of the control against Will not. As a result, the propeller motor 3 does not generate any additional torque or generates only a small amount of additional torque, so that no increased torque is introduced into the hull of the ship at the main fixed point.

Assuming that the propeller blades are in different positions, the load on the propeller shaft 17 is lowered, and the rotation speed n is increased again without increasing the motor torque. Since the rotation speed actual value n is now larger than the virtual rotation speed nominal value n * -n _R , the amplitude of the regulator output signal drops and the system returns to the initial operating point. As such, the rotational speed during one period can only be changed downward, so that the average value of the rotational speed n decreases slightly compared to the actual constant rotational speed nominal value n *, which is about 0.2 to 3%. This is evidence of a permanent control error. In order to compensate for this effect, a compensation circuit can be inserted in the reference variable channel, ie between the control lever 1 and the addition point 9, and virtually upwardly moving the rotational speed nominal value n ^* by a corresponding amount. Let's do it.

In this case, it is possible to take advantage of the fact that the load torque of the propeller 4 rises approximately to the square of the rotational speed n of the propeller, in particular in the case of the propeller of the ship, as a result of which it is fed back through the resistance and in a steady state. The feedback signal, which is approximately proportional to the drive torque of the propeller motor 3 in Fig. 3, corresponds approximately to the nominal value of rotation speed n ^* as a square-law function of the mean value of rotation speed n ~. The compensator should therefore have a branch which rises to the square of the rotational speed nominal value n *.

The line 13 may comprise in a suitable way a function transmitter 37 which generates the compensation described above and supplies it as a signal N _L ^{* to} the addition point 38 on the line 7. As a result, the rotational speed nominal value n ^* rises by the value _nL ^* f (n). Thus, in a steady state, n _L ^* = -n _R , which has the desirable effect that the sum of the signal 8 and the signal 35 becomes equal to the signal 6 at the addition point 9.

In the embodiment shown in FIG. 2, the variation of the regulator output signal proportional to the torque is returned to the rotational speed regulator input with a phase shift of approximately 180 °, thus firstly causing negative feedback and i.e., stable feedback, Secondly, the torque required to adjust the load-dependent fluctuations in the rotational speed and the regulator output signal approximately proportional thereto are reduced. This main result is that the fluctuations in the drive torque can be significantly reduced, and the torque fluctuations sent out by the motor fixed to the ship's hull and the torque fluctuations released through the ship's propellers to the ship's propeller track area are non-critical. Can be reduced to a value. One side effect of this case is that the propeller's rotational speed no longer remains exactly constant afterwards, but rather is subject to constant fluctuations as induced by alternating loads. However, this has very little importance for the propulsion produced by the propeller, while on the one hand it is advantageously possible to use the moments of inertia of the rotor, propeller and shaft of the electric motor to dampen this variation in this case. Since the rotary bearing for the shaft is virtually frictionless, the hull of the ship is not stimulated by this rotational speed variation.

From a hydrodynamic point of view, this effect has the important advantage that the propeller's rotational speed no longer remains exactly constant afterwards but is subject to some variation caused by alternating loads. As a result, this reduces the variation due to the hydrodynamic connection of the wake region to the travel angle. This reduction in the propagation angle is such that the variation of the load on the propeller blades located in the non-uniform wake region of the skeg or propeller shaft stay located on the ship hull induces a change in rotational speed by the above-described effect of the present invention. Due to the fact. Based on its direction and size, the change offsets the cause. This induces a change in rotational speed, which mitigates the fluctuations in the propagation angle of the propeller blades, which accounts for most of the cavitation risk. The response from this propeller blade to the other blades of the propeller due to the aforementioned effects is not critical, as the propeller is located in the non-uniform portion of the wake area of the skeg or propeller shaft stay provided with the blade's operating point on the ship's hull. This is because the propeller's rated operating point is kept significantly closer than the blade's operating point.

Within the scope of the present invention, the output signal fed back from the rotational speed regulator is multiplied by a factor. Of course, this feedback should not be chosen to be too strong, otherwise the rotational speed regulator is no longer selected by itself, since an approximately constant average value of the drive torque that is also fed back will result in an excessive reduction in the generated rotational speed nominal value. Rotational speed nominal values do not accelerate the propulsion shaft (assuming these rotational speed regulators have PI characteristics). The reason is that, on the other hand, the selected voltage range, for example -10V to + 10V, corresponds to the maximum rotational speed and maximum motor torque for forward and rearward propulsion respectively for both regulator input and output signals. This can be used with limitations, and multiplication of these two signal levels is essential to select the optimal feedback level.

The multiplication factor may be between 0.01% and 5%, preferably between 0.1% and 3.0%, particularly preferably between 0.15% and 2%. This is a natural negative feedback at a very low level because, as already mentioned above, much of the power required by the changing load can actually be provided by the moment of inertia of the rotor, propeller and propulsion shaft of the electric motor. In each case, the feedback can be fed back.

Since the present invention causes a certain amount of freedom against rotational speed fluctuations, the propulsion operation is energy that moderates the power consumption from the electric power supply network for the propulsion system, in a manner similar to the energy storage capacitors in the electric power supply. It can be used as a storage feature. Thus, a small amount of negative feedback has the important result that the torque applied by the propulsion motor is greatly mitigated without generating any significant and permanent control error from the preselected nominal value.

For some negative feedback, the setting is evidence that the steady state control error at rated load is between approximately 0.2% and 2%. In this case, despite the negative feedback of the regulator output signal, the closed loop control characteristic does not adversely affect the dynamic response to changes in the rotational speed nominal value in particular.

One method of preferred compensation according to the present invention uses the estimated average load during propulsion as an output variable, attempts to determine the expected steady state control error by mechanical recording of the path parameters, and the appropriateness of the nominal speed of rotation. Attempt to compensate for this control error using mutual adjustment.

In many cases, the properties of the controlled system are at least approximately known, especially in the case of marine propeller propulsion systems. In particular, in steady state, the average load torque based on the characteristic value is obtained from the steady state rotational speed actual value. As an example, in the case of propeller propulsion systems, the drive torque increases approximately to the square of the actual rotation speed. If the rotational speed actual value is intended to correspond to a specific rotational speed nominal value, it is possible to use this property to roughly determine the torque approximately proportional to the steady state regulator output signal, and thus feed back. The mean value of the signal and the residual control error can be determined. It is superimposed on the nominal value and is preferably additive so that an ideal rotational speed nominal value is obtained as the rotational speed actual value itself when a precomputed control error occurs.

By reducing the vibration amplitude, no expensive reinforcement of the ship hull in the critical point region calculated using the finite element method is required. This not only results in a significant reduction in computational complexity and design effort, but also results in significant material savings and shortening of assembly time.

Vibration suppression filter means in the ship hull due to non-uniformity during rotation of the propeller 4 of the ship can be suppressed using a traditional low-pass filter. The cut-off frequency of the low pass filter is in this case readjusted as a function of the speed of rotation of the propeller shaft 17 for convenience.

This aim is to further suppress low frequency components without adversely affecting the closed loop control system dynamic response at low propeller rotational speeds, and consequently, at high rotational speeds as well. The rotational speed of the ship propeller 4 still passes through a range greater than ten squared. In some cases, a fixed cut-off frequency is not sufficient. Such a low pass filter may be generated by a digital solution while filtering is performed by a convolution function with an appropriate cut-off frequency.

Instead of performing the filtering process in the frequency domain, ripple can also be suppressed by performing the filtering process in the amplitude domain. 3 schematically shows the signal generated at the output of the PI regulator 10 without any filtering. As shown, this consists of a reflow superimposed on a steady state component, which has already been described many times above.

The filtering is performed by using a microprocessor and the program inherent in the microprocessor causes the lower limit 39 to be determined, which is below the valley of the oscillation amplitude of the ripple. The upper limit 40 is formed in accordance with the lower limit 39 with a specific safety margin from the peak of the ripple. As long as the signal enters between these upper and lower limits 39, 40, the previously formed average value, such as the average between the upper and lower limits 39, 40, is passed to the control input 12. Appropriate readjustment is performed only when one of the upper and lower limits 39, 40 is involved as a result of the occurrence of a large error due to the movement of the control lever 1.

Such amplitude filtering can be particularly easily performed using a microprocessor. However, it is also possible for this purpose to use nonlinear amplitude characteristics, such as provided by diodes. This amplitude filter is conveniently accommodated between the addition node 9 and the input of the proportional regulator 33.

Nonlinear transmission relationships result in ripple being suppressed in the zero region, while large signals are passed through.

4 shows a block diagram of a marine propulsion system according to the present invention, in which a second filter means 41 is implemented, which allows for a possible dynamic response from the actuating device and the propeller motor and which is tolerated. Is used to respond to the propulsion dynamic response. Cavitation in the ship's propeller is suppressed during the acceleration process.

The functional group already described above occurs in the present block diagram, which will not be described again, and reference numerals in the previous figures are used for this functional group. The first filter means and the compensation circuit are omitted in FIG. 4 for the sake of simplicity.

The second filter means 41 for the ship propulsion system as shown in FIG. 4 comprises a ramp-up transmitter 42. The ramp-up transmitter 42 is located on a connecting line 7 connecting the control lever 1 to the nominal value input 8 of the addition node 9. Thus, the second filter means 41 is located in the reference variable channel.

Another element of the second filter means 41 is the characteristic transmitter 43, which is connected via line 45 to the control input 44 of the ramp-up transmitter 42. On the input side, the characteristic transmitter 43 is connected to the output of the circuit assembly 46, on which the rotational speed signal is provided from the connection line 13. Circuit assembly 46 is used to generate the magnitude of the rotational speed signal.

The purpose of the second filter means 41 is to limit the rate of change to a value that ensures that the nominal value signal as it arrives from the control lever 1 does not have a propensity for the propeller of the vessel to cavit without foaming. do. Regardless of how fast the control lever 1 moves in terms of acceleration, the nominal value at the appropriate input of the addition node 9 only moves at a low rate.

Such filter means can preferably be generated in the basic microprocessor. In order to achieve a certain limit, the signal coming from the control lever 1 can be differentiated, for example, and restricted according to the characteristic transmitter 43, and then integrated again to obtain the basic signal, but the elevated rate is not changed later. Do not.

For this reason, the characteristic transmitter 43 receives a signal dependent on the rotational speed, because the limit of the change rate depends on the ramp-up time for the rotational speed of the propeller 4 of the ship. Since the magnitude of the actual rotational speed of the propeller shaft 17 is used as a reference variable for the adaptive characteristic transmitter 43, it is used indirectly as a reference variable for the rate of rise of the nominal value signal passing through the closed loop control device 2. .

5 shows a characteristic profile for the second filter means 41. The property is continuous, ie not discontinuous, and is a roughly polygonal line. The characteristic 47 for normal operation consists of three sections 48, 49 and 50, which are plotted against the actual rotational speed of the propeller 4 of the ship.

In the exemplary embodiment shown, the low actual speed range 48 extends from 0 to 46 rpm (approximately one third of the rated rotation speed), and the central actual speed range 49 It extends from 46 to 70 rpm (about half of the rated rotation speed), and the upper actual rotation speed range 47 extends from 70 to 150 rpm (up to the maximum rotation speed).

As shown in FIG. 5, a constant and short ramp-up time in the dimension of seconds per rpm is characteristic transmitter for the ramp-up transmitter 42 which is adaptive for the low actual speed range 48 of the electric propeller motor 3. Predetermined at 43, which may correspond, for example, to a range between 0 and 1/3 of the rated rotational speed. The electric propeller motor 3 and thus the ship propeller 4 can operate with a high dynamic response in this range of motion.

In FIG. 5, with respect to the central actual rotation speed range 49 of the electric propeller motor 3, it is located between approximately one third and half of the rated rotation speed of the electric propeller motor 3, and the ramp-up time is relatively Rise as a shallow slope. Between these two limitations to the central actual rotation speed range 49, the characteristic transmitter 43 of the adaptive ramp-up transmitter 42 is changed to the propulsion mode, which is the higher actual rotation speed range of the electric propeller motor 3. Corresponds to (47). There is a ramp-up time that increases with the actual rotational speed of the electric propeller motor 3 at a steeper slope than the central actual rotational speed range 49. Here, the characteristic transmitter 43 for the second filter means 41 gives rather longer ramp-up time. The ramp-up time dependent on the rotational speed allows the electric propeller motor 3 to be constantly accelerated without any current limitation. This results in continuous vessel acceleration, as shown in FIG. This acceleration curve has no discontinuity.

In the course of the deceleration, the constant ramp-down time is characterized in that it can be set in advance in the second filter means 41, which may for example be 0.2 seconds per rpm.

The shape of the characteristic 47 allows the electric propeller motor 3 to be accelerated so that the propeller 4 of the ship is sufficiently accelerated to be freely variable. From a hydrodynamic point of view, this gives rise to the great feature that the operating point of the ship propeller 4 can be influenced in a characteristic manner consistent with optimum acceleration in the high rotational speed range 47 or propulsion mode. Thus, even during acceleration or even damage or cavitation, the operating point of the propeller 4 of the ship may escape from an undesirable area. This is a major financial feature because the cavitation in the ship propeller 4 results in significant noise, which significantly reduces the utility of passenger ships, survey ships and naval ships in particular.

Another characteristic for the ramp-up time can be stored in the characteristic transmitter 43 for the second filter means 41. For example, FIG. 5 shows a characteristic 51 for emergency motion in a region that is partly broken, which is distinct from the characteristic 47 for normal operation. Rapid acceleration can be allowed by selecting the characteristic 51 for emergency movement, for example by operating a button on the characteristic transmitter 43. For ships propelled according to the propulsion device according to the invention, the ramp-up time for the maximum speed of the ship is reduced by, for example, up to half, using the characteristic 51 for emergency movement, taking into account only the mechanically dependent limits. Can be. In contrast, for example, the configuration of the characteristic 47 may include other aspects as the configuration of the general characteristic that is selected in accordance with the trade-off between the appropriate ship motion characteristics and the operation of the overall mechanical system in the traditional manner. Optimization is possible in terms of various target functions such as minimum fuel consumption, minimum time lapse, high ship motility, and the like.

The alternative profile for the section 48 of the characteristic 47 at the characteristic transmitter 43 with respect to the second filter means 41 has a slight slope, but this is smaller than the slope of the section 49.

Further, in the characteristic transmitter 43, as the rotational speed of the propeller motor 3 increases, it is possible to rise according to the square law, and also to emphasize a certain offset somewhat, so that a short ramp-up time is required. Is actually set when (3) rotates at a low rotational speed. Another way is to omit the circuit assembly 36 for the second filter means and to extend the characteristic transmitter 43 by adding a negative rotational speed range of the propeller motor.

If the vessel is provided with two propulsion devices according to the invention as described above, the load distribution between the propeller shafts 17 of the two electric propeller motors 3 is controlled using an adaptive ramp-up transmitter 42. . The propeller shaft 17 with low load in this case has a somewhat lower actual rotation speed than the propeller shaft 17 with high load. In the high actual rotation speed range 50, that is, in the propulsion mode region of the electric motor 3 or the electric propeller motors 3, the adaptive ramp-up transmitter 42 with a low rotation speed actual value has a high rotation speed actual value. It is always accelerated faster than the adaptive ramp-up transmitter 42 with. While the ship is accelerating, this action leads to a substantially automatic uniform load distribution between the two propeller shafts 17. This leads to better directed stability during acceleration.                 

The response of the second filter means 41 of the propulsion device according to the invention means that the steady state load torque can be added to the definable acceleration torque. This definable acceleration torque remains in the propulsion mode range, i.e., it remains somewhat constant in the region of the high actual rotational speed range 47 of the electric propeller motor 3, so that sometimes there is no unnecessary high value. By interaction with the first filter means already described and with the second filter means 41 being reconditioned, this in particular prevents the propeller 1 of the ship from cavitation or foaming.

Suitable circuitry for the reconditioning of the ramp-up transmitter 42 inherent in the second filter means 41 by the rotational speed regulator is known in the art. This is not shown in the figures for simplicity.

Figure 7 shows a schematic block diagram of a ship propulsion system according to the invention, which is used to match the possible dynamic response from the actuating device and the third filter which the propeller motor is used to permit and permit the dynamic response of the generator system. Means 55. As a result, voltage and / or frequency variations in the on-board power supply network are suppressed during the acceleration and deceleration processes.

The aforementioned functional group occurring in this block diagram is not described again, and reference numerals from the previous drawings are used as is for the functional group. The first and second filter means and the compensation circuit are omitted for simplicity in FIG.

The on-board power supply network 5 is supplied from a diesel generator system 56 with four diesel generators 57, 58, 59, 61. The generator in this case is a normal three phase synchronous generator.

The third filter means 55 has a limiting circuit 62 located between the output of the regulator 10 and the control input 12 of the actuating device 6.

The purpose of the limiting circuit 62 is to be able to increase or decrease the output signal from the regulator 10 in accordance with the amplitude, or to limit the excessively fast rise rate. The limiting circuit 62 has two control inputs 63, 64 which are connected to the upper and lower limit value stages 65, 66. The upper and lower limit stages limit the ratio in the signal that can be varied up and down, respectively, via the control inputs 63 and 64, which also have the property of defining the amplitude window.

As long as the change in amplitude of the output signal from the regulator 10 fluctuates inside this window, the rate of change is not affected by the limiting circuit 62. The limiting circuit 62 is only started when the amplitude of the output signal from the regulator 10 varies more distinctly than is limited by the two limiting stages 65, 66.

The center and size of the amplitude window defined by the two limiting value stages 65, 66 is not fixed, because the two limiting value stages 65, 66 have control inputs 67, 69. . The control inputs 67 and 69 are connected to one output of the characteristic transmitter 72 having two control inputs 73 and 74, whereby the ramp-up time and the ramp-down time are limited. Since the input unit 74 is connected to the control input unit 12 via a suitable line, it receives information about the instantaneous value of the reference variable passing through the operating device 6.

The control input 73 is connected to one output of an additional other characteristic transmitter 75, which, on the one hand, is supplied with the magnitude of the rotational speed signal as the signal arrives from the circuit assembly 45, and the other On the one hand, a control signal from the logic circuit 76 is supplied. Logic circuitry 76 is connected to switches 78, 79, 81, 82 via control line 77, through which individual generators 57, 58, 59, 61 are connected to an on-board power supply network 5. ) The characteristic transmitter 75 defines a ramp-up time and a ramp-down time for the ramp-up transmitter 72.

The magnitude of the amplitude window, which is likewise limited by the two limiting value stages 65, 66, is not fixed because the two limiting value stages 65, 66 have control inputs 98, 99. . The control inputs 98, 99 are connected to one output of an additional other characteristic transmitter 97, which, on the one hand, as the signal arrives from the circuit assembly 45 as described above. The magnitude of the rotational speed signal is supplied and, on the other hand, a control signal which is made available to the logic circuit 76 as described above is supplied.

The limit value stage 65 is an adder for convenience, and the limit value stage 66 is a subtractor. The output from the ramp-up transmitter 72 passes through the control input 12 of the actuating device 6 to generate a steady state of the torque-forming control signal. The output of the characteristic transmitter 97 passes through the control input 12 of the actuating device 6 and generates a maximum sudden signal change in the torque-forming control signal that is acceptable for the steady state at each operating point.

Thus, the third filter means 55 limits the maximum permissible rate of change in which the nominal value signal for the actuating device 6 can be varied, whereby the rotational speed of the propeller motor or motors 3 is dependent on the propeller motor ( It can be precisely varied as a function of the rotational speed of 3) and the number and load of diesel generators connected to the on-board power supply network.

The time change is performed in relation to the limit value stages 65 and 66, i.e., the rate of change of the signal is only affected when the amount of signal change formed in the limit value stage is excessive. The windows formed in this way are characterized by the number of diesel generators 57, 58, 59, 61 connected to the on-board power supply network 5, the rotational speed of the propeller motor 3, and the actuating device 6. It depends on the magnitude of the control signal.

In this way, the rate of change of power consumption by the propeller motor or motors 3 is the value at which diesel drives the diesel generators 57, 58, 59, 61 and / or excessive voltage fluctuations and / or on-board The field excitation of the synchronous generator is limited to a value that can be followed without causing excessive frequency variation in the power supply network 5.

In order to allow the ship to continue to be in good motion and to not cause any control vibrations, however, the amplitude region of the signal located at the instantaneous value of the control signal of the input unit 12 is determined by the rising rate or falling rate. Not affected by restrictions. If this is not the case, the change in the instantaneous value (by closed loop control of the drive) due to the rate of change limiting becomes dangerous and becomes beating during operation.

Thus, the third filter means is used to preset the ramp-up time and ramp-down time for the reference variable, which are transmitted to the control input 12. The maximum allowable time to load the diesel engine in the diesel generator and the removal of the load from the diesel engine take into account this selected time. In order to take this into consideration, the ramp-up time and ramp-down time defined for the third filter means 55 vary in proportion to the magnitude of the rotational speed of the propeller motor 3. The time may vary based on the load at any time given to the diesel engine in the generator system.

FIG. 8 shows the characteristic 83 provided by the characteristic transmitter 75 when a single diesel generator is connected to the on-board power supply network 5.

As shown, the minimum ramp-up time and ramp-down time are defined within the low rotational speed range of the electric propeller motor (horizontal straight section), which approximately corresponds to the area of motion, ie approximately 1 / time of the rated rotational speed. Ends at 3. The ramp-up time and ramp-down time are determined by the maximum allowable rate of change of reactive current component output by the synchronous generator when the diesel generator is on. As the rotational speed of the propeller motor 3 increases, the rate of change decreases, i.e., the maximum allowable time within the range in which the power consumption or emission of the diesel engine in the generator system changes, the rise of the curve 83 of FIG. It is longer as shown in the branch line.

When the on-board power supply network 8 is supplied from two diesel generators, the curve 84 is used. As shown in FIG. 8, this curve is located below the curve 83, that is, faster power changes are possible in both the horizontal and rising portions of the curve.

Although more generators are connected, each curve 85, 86 feeds three or four diesel generators 57, 58, 59, 61, respectively, which are turned on at the same time.

Of course, it is not desirable to start the propulsion load with all the diesel generators 57, 58, 59, 61 from the start. If the diesel generators 57, 58, 59, 61 are connected in series, as a function of the rotational speed of the propeller motor 3, ie as a function of the overall power consumption of the ship propulsion system, these results are shown in FIG. 9. Resulting in an allowable power change rate with the profile shown.

The left horizontal section including the left rising branch with reference numeral 87 corresponds to the corresponding portion of the curve 84 with only two diesel generators. Beyond the specific rotational speed corresponding to the power consumption, the third diesel generator is connected, so that the rate of change in power consumption is defined by curve 88, which curve 87 is rapidly merged. Even if the power consumption is quite large, the power can vary along curve 89 since the fourth diesel generator is finally connected.

The maximum permissible rate of change of the reference variable is appropriate at the input 12 and has a rough tooth profile and maintains roughly the value (even at high power ranges) corresponding to the movement with only two activated diesel generators. .

In a quasi-steady state, the regulator 10 should be able to control the nominal value passing through the actuating device 6 without any time limit. Otherwise, as described above, severe beats occur in the electric propeller motor 3, which manifests itself as mechanical vibrations in the ship. This may increase or initiate cavitation in the propeller 4 of the vessel. Therefore, the limitation on the rate of change does not work within the amplitude window described above.

If the amplitude change remains independent of the rate of change in this window, the third filter means 55 is ineffective. Since the regulator 10 and the actuating device 6 operate in a full dynamic response to this range, voltage fluctuations can occur in the on-board power supply network 5, which means that the synchronous generator of the diesel generator system 56 This cannot be followed quickly enough. As mentioned above, the actuating device 6 operates in accordance with a frequency changer or converter and generates an inductive current which causes voltage fluctuations due to the reactance of the synchronous generator. This is because the size of the window is set so that the power changes and flows into the on-board power supply network, resulting in a voltage drop across the reactance of the connected generator resulting in a voltage drop in all cases. It is within the maximum allowable voltage tolerance of the on-board power supply network 5. In the case of the on-board power supply network 5, very rapid voltage fluctuations within the allowable voltage tolerances are not critical to operation.

The separation between the lower and upper edges of the window and the instantaneous value of the nominal value of the control input 12 is a function of the magnitude of the rotational speed of the propeller motor 3, which means that the power factor on the on-board power supply network side is different from each other. This is because it depends on the drive level of the operating device 6. The size of the window is also proportional to the number of synchronous generators of the diesel generator system 56 supplied to the on-board power supply network 5. The reason for this is that the high short circuit is the higher short circuit rating of the on-board power supply network, which in turn is the result of the smaller reactance of the synchronous generator connected in parallel.

10 shows the deviation of the window relative to the nominal value at the control input 12, where the current is drawn as the propeller motor 3 is not dependent on the rotational speed. The smaller window is fixed between two curved runs 91 and provides a situation where one diesel generator is connected to the on-board power supply network. The somewhat larger window corresponding to the two curves 92 is obtained when there are two diesel generators, while the extended window corresponding to the distance between the two curves 93 for the two diesel generators is the on-board power supply. It is a window corresponding to two curves 94 when there are four diesel generators connected to the network 5.

11 shows schematically the width of the window when the propulsion power can be varied as a function of the rotational speed of the propeller motor 3. The width of the window is represented by two fracture curves 95.

The curve starts with two diesel generators connected at low rotational speeds. Other diesel generators start operating at the first discontinuity point originating from the left, while four diesel generators operate at the right side of the second discontinuity point.

It is also desirable for the ramp-up time and ramp-down time of the nominal value at the control input 12 to vary as a function of the operating state of the diesel generator system to which electrical power is supplied to the on-board power supply network. In this case, other diesel generators of the diesel generator system can be used for different operating conditions.

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The particular arrangement of the third filter means 55 at the input of the regulator 10 suppresses an excessively fast control process due to the load loaded on the propeller 4 of the ship without depending on the movement of the control lever 1. . Occurs when the rudder is provided or when the load change moves back to the null position. The load change causes a change in rotational speed which must be adjusted and results in different power consumption. The regulator 10 is inherently very fast and can over-control the on-board power supply network if not limited by the third filter means 55.
It is apparent that the three aforementioned filter means can be used in any combination with each other.

Filters and closed loops and open loops have been described above in the form of traditional schematic electrical circuit diagrams, which facilitate understanding. In practical implementation, however, filters, closed loops, and open loops are generally in the form of programs or portions of programs. The nature of the description does not imply any limitation to any particular form in practice, as it is clear to those skilled in the art that filters and regulators may be configured in digital form as a program. As described above, the digital mechanism allows the Peruvian control system to have a long term constant or a constant time variable.

The marine propulsion system includes an electrical on-board power supply network, the electrical propulsion system supplied from the network having an accessory closed-loop control system for the propeller motor. The rotational speed of the propeller motor is controlled by a higher level regulator, whose reference variable comes from the control level. Filter means are included to suppress adverse effects on the operation of the vessel resulting from propulsion systems with excessively high dynamic response.

Claims (63)

A marine ship propulsion system with an electric on-board power supply network (5), A control lever device having a control lever 1 and outputting a control lever signal corresponding to the position of the control lever 1 from the output 7 of the control lever; A current / voltage source 56 for the generation of electrical power, An electric actuating device 6 having a power input unit, a power output unit 19, and a control input unit 12, wherein the power input unit is connected to the current / voltage source 56; An electric propeller motor 3 driving the propeller 4 of the ship and connected to the power output 19 of the actuating device 6; Rotational speed sensor means 14 for sending a rotational speed signal corresponding to the rotational speed of the propeller 4 of the ship, Having a regulator output section 11, a nominal value input section 8, and an actual value input section 13, the control lever signal is supplied to the nominal value input section 8 and a rotational speed signal is supplied to the actual value input section. A regulator device (2) supplied to (13) and whose regulator output (11) is connected to the control input (12) of the actuating device (6); and A filter capable of suppressing the rate of change of the instantaneous value of the electric power transmitted by the operating device 6 to the propeller motor 3 as a rate of change of the instantaneous value of the electric power which is a cause of adversely affecting the operation of the ship. With means 2, 36, 41, 55, Ship propulsion system. The method of claim 1, The instantaneous value is a value of a DC voltage or a root mean square value of the AC voltage, Ship propulsion system. The method of claim 1, The instantaneous value is characterized in that the frequency of the AC voltage, Ship propulsion system. The method of claim 1, Disturbance is vibration in the hull of the ship, characterized in that the disturbance is due to the torque fluctuation from the propeller motor 3, Ship propulsion system. The method of claim 1, The disturbances are voltage spikes or frequency fluctuations of the on-board power supply network 5 and excessively of the control lever 1 in the sense that the disturbances reduce the rotational speed of the propeller motor 3. Characterized by the fast moving, Ship propulsion system. The method of claim 1, The disturbance is a voltage spike, voltage dips or frequency variation of the on-board power supply network 5, the disturbance being caused by changing the load on the propeller 4 due to the rudder movement and the propeller pitch Or due to changing the rotational speed of another propulsion operation in the case of a ship in another propulsion operation, Ship propulsion system. The method of claim 1, The disturbance is formed by dynamically changing the propeller 4 of the vessel as a function of the speed of movement, Ship propulsion system. The method of claim 1, The filter means (2, 36, 41, 55) is the signal at the control input (12) when the frequency of the amplitude variation is at least one of when the amplitude of the amplitude variation is above the predetermined limit and when the amplitude of the amplitude variation is below the predetermined limit. Characterized in that it comprises a first filter means set to suppress an amplitude variation of Ship propulsion system. The method of claim 8, The first filter means is an amplitude filter means, Ship propulsion system. The method of claim 8, The first filter means is characterized in that the frequency filter means, Ship propulsion system. The method of claim 8, The first filter means is located upstream of the actual value input part 17 so that the actual value signal is provided via the first filter means, Ship propulsion system. The method of claim 8, The first filter means is characterized in that disposed between the regulator output unit 11 and the control input unit 12, Ship propulsion system. The method of claim 8, The first filter means 36 is characterized in that it is integrated in the regulator device 2, Ship propulsion system. The method of claim 8, The first filter means is characterized in that each filter characteristic value is formed so as to depend on the rotational speed of the propeller 4 of the ship, Ship propulsion system. The method of claim 8, The first filter means has a filter means control input to which a rotational speed signal is supplied, Ship propulsion system. The method of claim 1, The regulator device 2 is characterized in that it has a PI characteristic, Ship propulsion system. The method of claim 1, Characterized in that at least one of the regulator device 2 and the first filter means is configured to operate in a digital form, an analog form, or a mixed form of analog / digital, Ship propulsion system. The method of claim 1, Characterized in that at least one of the regulator device 2 and the filter means is in the form of a program in a microprocessor / microcontroller, Ship propulsion system. The method of claim 1, The regulator device 2 comprises, in series, a proportional regulator 33, an integral regulator 34, and an adder element 35 while one input of the proportional regulator 33 has the closed loop control deviation. An input to be supplied, one output of the proportional regulator 33 is connected to one input of the integral regulator 34, and another output of the proportional regulator 33 and the integral regulator 34. Characterized in that the output of is connected to the input of the adding element 35, the output forming the regulator output and fed back to the input of the proportional regulator 33, Ship propulsion system. The method of claim 19, The feedback 36 is set to induce a steady state closed loop control error of 0.2% to 2% at rated load, Ship propulsion system. The method of claim 20, The steady state closed loop control error is compensated for by the corrected nominal value n *, Ship propulsion system. The method of claim 21, Characterized in that the nominal value compensation (n _L *) is performed as a function of the estimated load, Ship propulsion system. The method of claim 22, Wherein the load is determined based on characteristics from an uncompensated rotational speed nominal value, Ship propulsion system. The method of claim 1, The actuating device 6 is characterized in that it is in the form of a regulator in which a nominal value input forms the control input 12 for the actuating device 6. Ship propulsion system. The method of claim 1, The operating device 6 is characterized in that the direct current voltage is output from the power output 19 of the operating device and the value of the direct current voltage is dependent on the position of the control lever 1, Ship propulsion system. The method of claim 1, The operating device 6 is characterized in that the power output 19 of the operating device sends out an alternating voltage and the frequency of the alternating voltage is dependent on the position of the control lever 1, Ship propulsion system. The method of claim 1, The operating device 6 is characterized in that the operating device 6 is configured to regulate the current transmitted to the propeller motor 3 via a signal at the control input 12, Ship propulsion system. The method of claim 1, The filter means 41 comprises a second filter means 41 in the form of a controlled ramp-up transmitter such that the rotational speed of the propeller motor 3 is in terms of acceleration as a function of the characteristic 47. It is characterized by limiting the ramp-up time within the range following the position of the control lever 1, Ship propulsion system. The method of claim 28, The property 47 is characterized in that the property 47 is continuous in the absence of discontinuity, Ship propulsion system. The method of claim 28, The second filter means 41 is characterized in that it is located between the control lever 1 and the nominal value input section 8 of the closed loop control device 2, Ship propulsion system. The method of claim 28, The second filter means 41 has a control input 44 to which the rotational speed signal is supplied, Ship propulsion system. The method of claim 28, The ramp-up time is characterized in that it is constant and short in the rotational speed range 48 between 0 and 1/3 of the rated rotational speed, or short while rising slightly. Ship propulsion system. The method of claim 28, Characterized in that the ramp-up time rises more rapidly in accordance with the rotational speed of the propeller motor 3 with respect to the rotational speed range 49 of the propeller motor 3 over a quarter of the rated rotational speed, Ship propulsion system. The method of claim 33, wherein The ramp-up time increases more rapidly than the rotational speed range below half of the rated rotational speed and more than the upper rotational speed range 50 above half the rated rotational speed, along the rotational speed of the propeller motor 3. Characterized by a sharp rise, Ship propulsion system. The method of claim 28, The second filter means 41 is characterized in that it is configured to operate in a digital form, an analog form, or a mixed form of digital / analog, Ship propulsion system. The method of claim 28, The ramp-down time predetermined in the second filter means 41 is equal to or shorter than the ramp-up time, and the ramp-up time is up to 1/4 of the rated rotational speed of the propeller. Characterized in dependence on the rotational speed in the rotational speed range 48, 49 of the motor 3, Ship propulsion system. The method of claim 28, The ramp-down time predetermined in the second filter means 41 is constant or shortened as the rotational speed of the propeller motor decreases, Ship propulsion system. The method of claim 28, The ramp-down time predetermined in the second filter means 41 is characterized in that the ramp-down time is continuous in terms of no discontinuity, Ship propulsion system. The method of claim 28, Characterized in that the ramp-down time predetermined in the second filter means 41 is 0.2 seconds per rpm, Ship propulsion system. The method of claim 1, The filter means 2, 36, 41, 55 have a third filter means 55 which limits the rate of change of power consumption by the propeller motor 3, Ship propulsion system. The method of claim 40, The third filter means 55 closes the electrical actuating device 6 with respect to the limiting value dependent on the current / voltage source 56 which supplies electrical power to the on-board power supply network 5. Characterized in that it is set to limit the rate of change of the output variable from the loop control device 2, Ship propulsion system. The method of claim 40, The third filter means 55 changes the rate of change of the output variable in one direction referred to as the ramp-up time or ramp-up change rate, and the output variable in the other direction referred to as the ramp-down time or ramp-down change rate. Characterized in that it is configured to limit to a value different from the rate of change of Ship propulsion system. The method of claim 42, At least one of the value for the ramp-up time and the value for the ramp-down time limited by the third filter means 55 is equal to the change in the magnitude of the actual rotational speed of the electric propeller motor 3. Characterized in that it can be varied, Ship propulsion system. 42. The method of claim 41 wherein In the low rotational speed range of the electric propeller motor 3 or the propeller 4 of the ship, the ramp-up time and ramp-down time predetermined by the third filter means 55 are determined on the on-board. Characterized in that the maximum allowable change ratio of the reactive current component sent out by the current / voltage source 56 supplied to the power supply network 5, Ship propulsion system. 42. The method of claim 41 wherein The current / voltage source has two or more generators 57 ... 61, wherein at least one of a ramp-up time and a ramp-down time predetermined by the third filter means 55 is determined by the active generator. It can be varied in terms of the opposite to the change in any one or more of the number and physical size, Ship propulsion system. 42. The method of claim 41 wherein Characterized in that any one or more of the ramp-up time and ramp-down time predetermined by the third filter means can be varied as a function of the operating state of the current / voltage source 56, Ship propulsion system. 42. The method of claim 41 wherein The third filter means 55 is configured such that a window is provided within a range in which at least one of the ramp-up time and the ramp-down time is not limited. Ship propulsion system. The method of claim 47, The position of the window is necessarily symmetrical with respect to the output variable in at least one range of the output variable from the closed loop control device 2, so that the restriction occurs at the same rate of change in both directions, Ship propulsion system. The method of claim 47, In order to provide the window, the output signal from the closed loop control device is fed back to the control input unit 74 of the third filter means 55, Ship propulsion system. The method of claim 47, The size of the window is such that the reactive current of the on-board power supply network due to the rate of change in power consumption of the propeller motor 3 is supplied across the reactance of the current / voltage source 56 to the on-board power supply. Characterized in that the voltage can be adjusted to drop within the maximum allowable voltage tolerance range of the network 5, Ship propulsion system. The method of claim 47, The current / voltage source 56 has at least two generators 57 ... 61, the size of the window being greater than the number of activated generators 57 ... 61, Ship propulsion system. 42. The method of claim 41 wherein Characterized in that the ramp-up time and ramp-down time of the current nominal value are varied in terms of the same change in magnitude of the actual rotational speed of the electric propeller motor 3, Ship propulsion system. 42. The method of claim 41 wherein The ramp-up time and ramp-down time of the current nominal value are inversely variable in proportion to the physical size and number of generators 57 ... 61 that supply power to the on-board power supply network. , Ship propulsion system. 42. The method of claim 41 wherein The third filter means 55 is characterized in that it is configured to operate on a microprocessor basis in analog form or in a mixed form of digital / analog, Ship propulsion system. The method of claim 22, Characterized in that the load is determined on the basis of the characteristic from the rotational speed actual value, Ship propulsion system. The method of claim 1, The filter means 41 comprises a second filter means 41 in the form of a controlled ramp-up transmitter such that the rotational speed of the propeller motor 3 is dependent on the function of the rotational speed of the propeller motor 3. It is characterized in that the ramp-up time is limited within the range following the position of the control lever 1 in terms of acceleration, Ship propulsion system. The method of claim 28, Characterized in that the ramp-up time rises more rapidly in accordance with the rotational speed of the propeller motor 3 with respect to the rotational speed range 49 of the propeller motor 3 over one third of the rated rotational speed, Ship propulsion system. The method of claim 28, The ramp-down time predetermined in the second filter means 41 is equal to or shorter than the ramp-up time, and the ramp-up time is up to 1/3 of the rated rotational speed of the propeller. Characterized in dependence on the rotational speed in the rotational speed range 48, 49 of the motor 3, Ship propulsion system. The method of claim 28, The ramp-down time predetermined in the second filter means 41 is characterized in that it is considerably shorter than the ramp-up time dependent on the rotational speed in the subsequent rotational speed range 50 of the propeller motor 3. , Ship propulsion system. The method of claim 42, At least one of the value for the ramp-up time and the value for the ramp-down time limited by the third filter means 55 is variable in proportion to the magnitude of the actual rotational speed of the electric propeller motor 3. Characterized in that can be, Ship propulsion system. 42. The method of claim 41 wherein The current / voltage source has two or more generators 57 ... 61, and at least one of a ramp-up time and a ramp-down time predetermined by the third filter means 55 is the activated generator. Characterized in that it can be inversely proportional to any one or more of the number and physical size of, Ship propulsion system. The method of claim 47, The size of the window is such that the reaction current of the on-board power supply network due to the rate of change of the power consumption of the propeller motor 3 is the maximum of the on-board power supply network 5 across the reactance of the synchronous generator. Characterized in that the voltage can be adjusted to drop within the allowable voltage tolerance range, Ship propulsion system. 42. The method of claim 41 wherein The ramp-up time and ramp-down time of the current nominal value are variable in proportion to the magnitude of the actual rotational speed of the electric propeller motor 3, Ship propulsion system.

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