KR101361426B1 - Propulsion Apparatus For Ship - Google Patents

Abstract

Improves fuel economy by keeping constant output torque of internal combustion engine that propels ship.
The load torque Qa calculated on the basis of the detection signal from the load torque detector 22a is compared with the variation reference value Qs of the load torque participating in the power transmission path 12, and when the load torque Qa is larger than the variation reference value Qs, the generator motor 14 is compared. The amount of generated power is reduced, and when the load torque Qa is smaller than the variation reference value Qs, the amount of generated power is increased. In addition, when the load torque Qa is larger than the variation reference value Qs, the assist output of the generator motor 14 is increased, and when the load torque Qa is smaller than the variation reference value Qs, the assist output is decreased.

Description

Propulsion Apparatus For Ship

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ship propulsion device in which load fluctuations are not applied to an internal combustion engine due to disturbances such as waves of the water surface during ship navigation.

As a power source of a ship sailing on water by propulsion of a propeller, internal combustion engines, such as a diesel engine, are used normally, and the hybrid propulsion apparatus which has an electric motor as a power source is added to patent documents 1 and 2 in addition to an internal combustion engine. It is described. Such a hybrid propulsion device has a generator that is driven by an internal combustion engine and generates power. The hybrid propulsion device drives a generator while driving a propeller by an internal combustion engine during navigation of a ship, thereby charging power to the battery, and when the electric motor is driven, Supply power to the electric motor. In order to reduce the size of the propulsion device, a generator motor having a function of an electric motor and a generator is used.

In the hybrid propulsion system described above, the propeller is driven by an internal combustion engine during the normal navigation of the ship, and the propeller is driven by an electric motor during low speed or slow speed navigation and in the backward navigation with less use frequency. have. The propeller is driven by an electric motor at the time of slow speed navigation or reverse navigation, thereby eliminating the noise of the internal combustion engine, and supplying the electric power of the battery to the electric device during the selection and mooring.

On the other hand, Patent Document 3 discloses that when the load torque applied to the propeller exceeds the output torque of the internal combustion engine, the generator motor is operated in the assist mode to assist the motor torque to the propeller, and the load torque applied to the propeller is applied to the internal combustion engine. In the case of lowering the output torque of the ship, a propulsion device of a ship in which a generator motor is operated in a power generation mode is described. In this way, if the operating mode of the generator motor is changed to either the power generation mode or the assist mode by the magnitude relationship between the load torque and the output torque, the load of the internal combustion engine can be made constant.

Patent Document 1: Japanese Unexamined Patent Publication No. 2001-270495 Patent Document 2: Japanese Unexamined Patent Publication No. 2001-301692 Patent Document 3: Japanese Unexamined Patent Publication No. 2010-241160

However, in order to make the load of an internal combustion engine constant by changing the operation mode of a generator motor by the magnitude relationship between load torque and an output torque, it is necessary to measure load torque accurately. For example, a strain gauge that measures twist of the propeller shaft is used for the measurement of the load torque, but the residual stress of the propeller shaft cannot be confirmed when adjusting the zero point at no load when the internal combustion engine is stopped. Therefore, the measurement result of load torque contains the error, and load torque cannot be measured accurately.

If the operating mode of the generator motor is changed according to the magnitude of the load torque and the output torque, the values of the load torque and the output torque include variations in the generator output and the motor output. According to the relationship between the large and small, the output torque of the internal combustion engine cannot be controlled constantly, and fuel economy cannot be improved reliably.

In addition, when the magnitude relationship between the load torque and the output torque does not change for a long time, one of the power generation mode and the assist mode is continued for a long time. However, there are limitations in supplying electrical energy to the generator motor from a battery mounted on a ship for a long time, or charging the battery from the generator motor for a long time, such as battery capacity, switching control time, and the like.

An object of the present invention is to improve the fuel efficiency of an internal combustion engine by making it possible to maintain a constant output torque of an internal combustion engine for propelling a ship.

The propulsion device of the ship of the present invention is a propulsion device of the ship having a power transmission path connecting the propeller and the main shaft of the internal combustion engine to apply a propulsion force to the vessel, the generator is installed in the power transmission path and driven by the internal combustion engine to generate power , A power supply unit to which power generated by the generator is supplied, load torque calculating means for calculating load torque applied to the power transmission path, load torque calculated by the load torque calculating means and load torque applied to the power transmission path And a control means for reducing the amount of power generated by the generator when the load torque is larger than the value of the fluctuation reference value, and increasing the amount of generated power by the generator when the load torque is smaller than the change threshold.

The propulsion device of the ship of the present invention is a propulsion device of the ship having a power transmission path connecting the propeller and the main shaft of the internal combustion engine to apply a propulsion force to the ship, an electric motor, an electric motor installed in the power transmission path to assist the power propeller By comparing the variation of the load torque applied to the power transmission path and the load torque calculated by the load torque calculating means, and the load torque calculating means for calculating the load torque applied to the power transmission path. The control means for increasing the assist output of the electric motor when the load torque is larger than the variation reference value, and reducing the assist output of the electric motor when the load torque is smaller than the variation reference value.

The propulsion device of the ship of the present invention is a propulsion device of the ship having a power transmission path connecting the propeller and the main shaft of the internal combustion engine to apply a propulsion force to the ship, is installed in the power transmission path and driven by the internal combustion engine to generate power A generator torque assisting the propeller, a power supply unit supplied with power generated by the generator motor, a power source supplying power to the generator motor, load torque calculation means for calculating load torque applied to the power transmission path, And a change reference value of the load torque calculated by the load torque calculating means and the load torque applied to the power transmission path, and when the load torque is larger than the change reference value, the generator motor is operated by the power from the power source to the propeller. When assisting power and load torque is lower than fluctuation threshold It is characterized in that it was powered by the generator motor to the internal combustion engine having a control means for supplying electric power to the power supply blood.

The propulsion apparatus of the ship of the present invention is characterized in that the calculation of the load torque is calculated based on the amount of strain of the power transmission path or based on the rotation speed of the power transmission path.

According to the present invention, transmission of load fluctuations to the internal combustion engine is prevented, and therefore the output torque of the internal combustion engine can always be kept constant even if disturbance is applied to the ship, thereby improving fuel economy of the internal combustion engine.

By comparing the load torque applied to the propeller at the time of the voyage with the fluctuation standard value, the amount of power generated or the assist output can be controlled based on the amount of change in the load torque, and the amount of generated power and assist output can be controlled with high accuracy. Loss of load torque can be reduced, thereby improving fuel economy of the internal combustion engine.

By comparing the load torque and the fluctuation reference value, by changing the operation mode of the generator motor to the assist control mode and the power generation control mode, the influence of the load torque applied to the internal combustion engine can be reduced, thereby improving the fuel efficiency of the internal combustion engine.

1 is a block diagram showing a propulsion apparatus of a ship, which is one embodiment of the present invention.
Fig. 2 is a schematic diagram showing a state in which a ship is sailing on the surface where waves are generated.
3A is a schematic diagram showing a state where the water surface is changed with respect to the standard water level due to the generation of waves.
It is a schematic diagram which shows a change of ship speed by a wave.
It is a schematic diagram which shows the change of the load torque applied to the propeller by a wave.
It is a schematic diagram which shows the rotation speed of the internal combustion engine compared with the prior art, when load torque fluctuates by a wave.
4 is a time chart showing a power generation control mode in a propulsion apparatus of a ship.
5 is a time chart showing an assist control mode in a propulsion apparatus of a ship.
6 is a time chart showing an automatic switching control mode in a propulsion apparatus of a ship.
Fig. 7 is a characteristic diagram showing the relationship between the output torque of the engine and the rotational speed of the main shaft under the condition that the fuel supply amount to the engine is made constant.
8 is a block diagram showing a propulsion device according to another embodiment of the present invention.
Fig. 9 is a block diagram showing a propulsion device according to still another embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail based on drawing. As shown in FIG. 1, the propeller shaft 12a provided with propeller 11 for applying propulsion to the ship is connected to the main shaft 12b of the engine, that is, the internal combustion engine 13. The propeller shaft 12a and the main shaft 12b constitute a power transmission path 12, and the actual output of the engine, that is, the output torque, is transmitted to the propeller 11 via the power transmission path 12. The generator motor 14 is provided in the power transmission path 12, and the generator motor 14 has a function as an electric motor for powering the propeller 11 and a generator driven and generated by the internal combustion engine 13.

In order to satisfy the electric power demand of various onboard electric appliances 15 installed in the ship, a generator 16 is installed in the ship, and the electric power generated by the generator 16 is sent by the power line 17 to the onboard electric equipment 15. The electric equipment 15 on board serves as a power supply unit that is supplied with power and functions, and the generator 16 is a power source that supplies power to the power supply unit.

The generator motor 14 is connected to the onboard electric device 15 and the generator 16 via a power converter 18 having a frequency and voltage conversion function, and can supply power generated by operating the generator motor 14 as a generator to the power demand of the onboard electric device 15. have. On the other hand, when the generator motor 14 is operated as an electric motor to assist power to the propeller 11, the generator motor 14 can be supplied with electric power from the generator 16. In addition, the capacitor 19a is mounted in the ship, and the capacitor 19a is connected to the power line 17 via the charging / discharging board 19b. The capacitor 19a can supply the charged electric power to the generator motor 14 to operate the generator motor 14 as an electric motor, and at the same time, can charge the electric power generated by the generator motor 14. Thus, by providing the capacitor 19a in the propulsion device, the capacitor 19a constitutes a power source and a power supply portion.

Generator motor 14 and capacitor 19a are controlled by controller 20 as control means. The propulsion device shown in FIG. 1 is controlled by the controller 20, and can supply electric power from any of the generator 16 and the capacitor 19a to the generator motor 14, and generate electric power generated by the generator motor 14 on board. And the capacitor 19a. The controller 20 transmits a detection signal for the engine driving condition such as the rotation speed of the internal combustion engine 13 and the fuel supply amount, and controls the driving of the internal combustion engine 13.

As described above, the propulsion device shown in FIG. 1 can supply power to the generator motor 14 with any of the generator 16 and the capacitor 19a, and at the same time, the power generated by the generator motor 14 can be supplied to any one of the onboard electric equipment 15 and the capacitor 19a. It is in one form for supply. In addition to this form, there are a form in which electric power is supplied from generator 160,000 to generator motor 14 and a form in which electric power is supplied only from capacitor 19a to generator motor 14. Similarly, there are a form of supplying electric power generated by the generator motor 14 only to the inboard electric device 15 and a form of supplying only the capacitor 19a.

The strain gauge 21a is provided in the propeller shaft 12a, and a detection signal is transmitted from the strain gauge 21a to the load torque detector 22a by a radio signal. The strain gauge 21a transmits a detection signal corresponding to the torsional stress applied to the propeller shaft 12a to the load torque detector 22a at a cycle of, for example, 500 Hz. The strain gauge 21b is provided in the main shaft 12b, and a detection signal is transmitted from the strain gauge 21b to the load torque detector 22b by a radio signal. The strain gauge 21b transmits a detection signal in response to the torsional stress applied to the main shaft 12b to the load torque detector 22b at the same period as the strain gauge 21a.

The detection signal of each load torque detector 22a, 22b is sent to the controller 20 by a signal line, and the load torque of the propeller shaft 12a and the main shaft 12b can be calculated based on a detection signal. As shown in Fig. 1, two strain gauges 21a and 21b are provided in the power transmission path 12, but either strain gauge can calculate the load torque applied to the propeller 11 during the ship's navigation. have. In addition, the middle value of the value of the two load torques obtained based on the detection signals of two strain gauges 21a and 21b can also be made into a load torque.

Under the condition that propeller 11 is rotating at a substantially constant rotation speed, if disturbances such as waves and waves of the water surface are applied to propeller 11 and the load torque of the power transmission path 12 fluctuates, the warp stress of propeller shaft 12a and main shaft 12b changes. Therefore, the load torque applied to the propeller 11 can be calculated by the signals from the strain gauges 21a and 21b. However, in order to detect the load torque, an optical axial torque meter may be used instead of the strain gauges 21a and 21b.

The controller 20 includes a microprocessor (CPU) for calculating control signals, a ROM for storing control programs, arithmetic expressions, map data, and the like, and a RAM for temporarily storing data, and has a function as an arithmetic means. The controller 20 calculates the load torque based on data or calculation formula stored in the ROM based on the detection signals from the strain gauges 21a and 21b.

The controller 20 transmits a rotational speed signal corresponding to the actual rotational speed of the main shaft 12b and a supplying amount signal corresponding to the fuel supply amount actually supplied to the internal combustion engine 13, and based on this signal sent to the controller 20, The actual output torque Ta of the internal combustion engine 13 is calculated by this. Therefore, although the controller 20 has a function of calculating the output torque Ta of the internal combustion engine 13, it is possible to send a signal of the output torque to the controller 20 from an engine controller (not shown) controlling the internal combustion engine 13. The actual output torque Ta is a torque output from the main shaft 12b of the internal combustion engine 13 by subtracting friction loss and the like in the cylinder, and is also called a braking torque. As a calculation method of the output torque Ta of the internal combustion engine 13, the output torque of the main shaft 12b can be requested | required by an axial torque meter.

2 is a schematic diagram showing a state in which the ship is sailing on the surface of the water wave generated. As shown in FIG. 2, when the ship is sailing in the direction indicated by the arrow on the surface of the water, the ship may pass from the state S1 of rising wave to the state S2 of navigating the peak of the wave and the state S3 of descending wave. The lowest point state S4 of the wave is reached. When a ship navigates under periodic wave conditions, this navigation condition is repeated periodically.

FIG. 3A is a schematic diagram showing a state in which the water surface is changed with respect to the standard water level due to the generation of waves, FIG. 3B is a schematic diagram showing a change in ship speed due to the waves, and FIG. 3C is a load torque applied to the propeller 11 by the waves. It is a schematic diagram which shows a change of Qa, and FIG. 3D is a schematic diagram which showed the rotation speed of the internal combustion engine in the case where load torque Qa fluctuates by a wave compared with the past.

In the state S1 in which the ship approaches the wave and climbs the wave, the navigational resistance applied to the hull is increased by the wave and the speed of the ship decreases. Since the inflow speed of the water which flows toward the propeller 11 also falls by the fall of ship speed, the load torque Qa applied to the propeller 11 increases. The load torque Qa becomes maximum in the state S2 near the peak of the wave at which the ship speed becomes the lowest. On the other hand, after passing the peak of the wave, the navigational resistance caused by the wave decreases at once, and since the acceleration of gravity is added, the line speed increases rapidly and the load torque Qa decreases. Therefore, when waves occur on the surface of the ship while sailing, the ship speed and the load torque Qa change as shown in Figs. 3B and 3C. However, the changes in the ship speed and the load torque Qa are shown schematically in Figs. 3B and 3C, and the phases of the ship speed and the load torque Qa for the actual wave change are more complicated than the case shown.相).

As shown in FIG. 3C, the load torque Qa applied to the propeller 11 is fluctuated by disturbances such as waves applied to the ship. The load torque Qa applied to the propeller 11 is calculated by the controller 20 on the basis of the detection signals from the strain gauges 21a and 21b at the cycle described above. The controller 20 calculates the average value of the load torque Qa per unit time as the variation reference value Qs and stores it in the ROM. This variation reference value Qs is calculated by the average value of the load torque Qa in the past few seconds to several minutes, and is updated every time.

As the propulsion control mode of the ship using the variation reference value Qs, there are a power generation control mode and an assist control mode.

4 is a time chart showing a power generation control mode in a propulsion apparatus of a ship. In this power generation control mode, the output torque Ta of the internal combustion engine 13 is set to the sum of the torque of the torque for driving the propeller 11 and the torque for generating power by the generator motor 14. The output torque Ta of the internal combustion engine 13 is set constant by changing the power generation amount G of the generator motor 14 in response to a change in the load torque Qa applied to the propeller 11 due to a disturbance such as a wave applied to the ship. In this way, the output torque Ta of the internal combustion engine 13 can be kept constant at all times by canceling the fluctuation of the load torque Qa by the power generation amount G of the generator motor 14.

In order to cancel the fluctuation of the load torque Qa by the power generation amount G of the generator motor 14, the load reference torque Qa calculated based on the detection signal from the load torque detector 22a is compared with the change reference value Qs of the load torque. As a result, when the load torque Qa is larger than the variation reference value Qs, the power generation amount G generated by the generator motor 14 is reduced from the generation amount at the variation reference value Qs. On the other hand, when the load torque Qa is smaller than the variation reference value Qs, the power generation amount G by the generator motor 14 is made larger than the generation amount at the variation reference value Qs.

That is, if the difference between the calculated load torque Qa and the variation reference value Qs, i.e., the change amount is ΔQ (Qa-Qs), if the change amount ΔQ is positive (+), the amount of generated power is reduced in response to the increased load torque. On the other hand, if the change amount ΔQ is negative, the power generation amount is increased in response to the reduced load torque.

As described above, the variation reference value Qs is calculated by the average value of the load torque Qa between the past few seconds and several minutes, and is updated at the time of voyage of the ship. Therefore, the variation reference value Qs depends on the optimum variation reference value Qs along the sea. The load torque Qa can be compared. Thus, since the fluctuation | variation of the load torque Qa is absorbed by the generation amount of the generator motor 14, the internal combustion engine 13 can always be driven with constant output torque Ta.

5 is a time chart showing an assist control mode in a propulsion apparatus of a ship. In this assist control mode, propeller 11 is transmitted with output torque Ta of internal combustion engine 13 and assist output M of generator motor 14 functioning as an electric motor. The output torque Ta of the internal combustion engine 13 is set to a fixed value less than the torque required for driving the propeller 11. If the load torque Qa applied to the propeller 11 fluctuates due to a disturbance such as a wave applied to the ship, the output torque Ta of the internal combustion engine 13 is set constant by changing the assist output M of the generator motor 14 in response to this fluctuation. . Thus, by canceling the fluctuation of the load torque Qa by the assist output M of the generator motor 14, the output torque Ta of the internal combustion engine 13 can always be kept constant.

In order to cancel the change of the load torque Qa by the assist output M of the generator motor 14, the load reference torque Qa calculated based on the detection signal from the load torque detector 22a is compared with the change reference value Qs of the load torque. As a result, when the load torque Qa is larger than the variation reference value Qs, the assist output M by the generator motor 14 is made larger than the assist output M at the variation reference value Qs. On the other hand, when the load torque Qa is smaller than the variation reference value Qs, the assist output M by the generator motor 14 is reduced than the assist output at the variation reference value Qs.

That is, if the change amount which is the difference between the calculated load torque Qa and the variation reference value Qs is ΔQ (Qa-Qs), if ΔQ is positive (+), the assist output is increased in response to the increased load torque. On the other hand, if ΔQ is negative, the assist output is reduced in correspondence with the reduced load torque. In this way, since the variation of the load torque Qa is absorbed by the assist output of the generator motor 14, the internal combustion engine 13 can always be driven with a constant output torque Ta.

As shown in FIG. 1, in the propulsion apparatus with generator motor 14, it is a control form corresponding to the change amount of the load torque Qa with respect to the fluctuation reference value Qs, and it is automatically changed to either of a power generation control mode and an assist control mode according to a navigation condition. There is an automatic fluctuation control mode to switch to. In such a case, for example, the required propulsion force for obtaining the set flux and the periodic output, that is, the relationship between the internal combustion engine output, or the relationship between the demand and supply of power in the ship, or the charging capacity of the capacitor 19a, namely In accordance with the relationship of the remaining capacity, the control is automatically switched to either the power generation control mode shown in FIG. 4 or the assist control mode shown in FIG. 5. As another control mode, there is a system in which the operation of the crew is converted into either the power generation control mode or the assist control mode. In this case, the controller 20 is connected to the manual operation switch for inputting the control mode, and the operation signal of the manual operation switch is sent to the controller 20.

As described above, the load torque Qa at the time of navigation is calculated | required, and the change amount of the load torque Qa can be calculated | required from this by comparing the variation reference value Qs calculated | required by the previous load torque Qa from this. Since the amount of change is a relative value and does not include an error, control of the propulsion device based on the amount of change ΔQ enables high precision control based on the load torque Qa.

6 is a time chart showing an automatic switching control mode as another control mode in the propulsion apparatus of the ship.

In this automatic switching control mode, the load torque Qa is compared with the variation reference value Qs, and when the load torque Qa is larger than the variation reference value Qs, the generator motor 14 is driven by the power from the capacitor 19a as a power source to power the propeller 11. When the load torque Qa is smaller than the variation reference value Qs, the generator motor 14 is operated by the internal combustion engine 13 to supply electric power to the capacitor 19a serving as the power supply unit. In FIG. 6, the assisted motor torque is shown by hatching, and the generation torque applied to the generator motor 14 by the internal combustion engine 13 for power generation is shown by the point.

In this automatic switching control mode, the output torque Ta of the internal combustion engine 13 is set to a value close to this based on the variation reference value Qs. The fluctuation reference value Qs is calculated by the average value of the load torque Qa in the past few seconds to several minutes as described above, and the output torque Ta is set to a value substantially close thereto. A ship such as a wave or a tidal current When the difference between the fluctuation reference value Qs and the output torque Ta becomes larger than the threshold value due to the disturbance applied to the output torque, the output torque Ta is adjusted to a value close to the fluctuation reference value Qs. By making the calculation period of the threshold value longer than the calculation period of the variation reference value Qs, it is prevented that the output torque Ta is changed frequently. In this way, if the output torque Ta is controlled to approach the variation reference value Qs, it is possible to prevent the capacitor capacity from running short due to the bias between charge and discharge.

Therefore, when the ship sails on the surface where disturbances such as waves and waves fluctuate in a short period of time, and the load torque Qa applied to the propeller 11 increases more than the fluctuation reference value Qs, the generator motor 14 supplies the propeller shaft 12a to the propeller shaft 12a. Since the drive torque is assisted, the ship can be navigated without increasing the fuel supplied to the internal combustion engine 13, that is, without increasing the output torque Ta of the internal combustion engine 13. On the other hand, if the load torque applied to the propeller 11 is lower than the variation reference value Qs, the generator motor 14 is driven by the internal combustion engine 13, and the output torque of the internal combustion engine 13 is used as generated energy, so that the fuel supplied to the internal combustion engine 13 is reduced. The ship can be sailed without reducing the target output torque of the internal combustion engine 13.

When the propulsion device is controlled by each of the control modes described above, a certain amount of fuel is supplied to the internal combustion engine 13 on the surface where waves and waves are generated, and as shown in FIG. The ship can be sailed by keeping the output torque of the internal combustion engine constant, without changing the rotation speed. That is, the navigation which makes a constant output torque becomes possible. In this way, the output torque of the internal combustion engine 13 can be kept constant even when the load torque is applied periodically, so that fuel economy can be improved as compared with the case where the rotation speed of the internal combustion engine 13 is changed periodically.

7 is a characteristic diagram showing the relationship between the output torque of the internal combustion engine 13 and the rotation speed of the main shaft 12b while the fuel supply amount to the internal combustion engine 13 is constant. This characteristic diagram shows the characteristic of the diesel engine used as the internal combustion engine 13. The internal combustion engine 13 has the characteristic as shown in FIG. . In Fig. 7, reference numerals a to e each indicate a fuel supply amount, and a fuel supply amount indicates a small state along the direction from reference a to symbol e. The diesel engine has an output characteristic in which the output torque increases as the rotation speed increases, and the output torque becomes downward-sloping when the rotation speed becomes higher than the maximum output torque, that is, the predetermined rotation speed P which becomes the maximum horsepower. have. In the normal navigation of the ship, the spindle 12b is driven in the region of the down-speed gradient.

For example, when the ship is sailing in the state of point A in FIG. 7, conventionally, when the load torque applied to the propeller 11 by the wave or the wave increases, the rotation speed of the main shaft 12b is lowered. The fuel supply amount to the furnace can be increased, and the output torque can be increased to suit the increase in the load torque. On the other hand, when the load torque decreases, the rotation speed increases, so that the fuel supply amount decreases, and the output torque decreases to suit the reduction of the load torque.

Therefore, when the fuel supply amount is controlled for short-term disturbance as in the prior art, as shown in FIG. 3D, the engine speed is frequently changed, thereby deteriorating fuel economy. In addition, when the fuel supply amount is controlled, as shown in FIG. 3D, until the control is completed, there is a time lug T, so that the rotation speed of the main shaft 12b cannot be stably controlled in response to short-term disturbance. In contrast, in the present invention, by operating the generator motor 14 against short-term disturbances, the rotation speed of the main shaft 12b can be kept constant as shown in FIG. 3D even under disturbances.

As shown in FIG. 1, the generator transmission 14 which has the function of an electric motor and a generator is provided in the power transmission path 12, However, an electric motor and a generator can also be provided in a power transmission path, respectively. However, as shown in FIG. 1, when the generator motor 14 is arrange | positioned in the power transmission path 12, a propulsion apparatus can be miniaturized. If only the electric motor is provided in the power transmission path 12, when the load torque increases, motor power is assisted to the propeller shaft 12a. In this case, the assist output M of the electric motor is controlled in the assist control mode shown in FIG. 5. On the other hand, when only a generator is provided in the power transmission path 12, when a load torque falls, power generation is performed by a generator. In this case, the power generation amount G of the generator is controlled in the power generation control mode shown in FIG.

8 is a block diagram showing a propulsion apparatus for a ship according to another embodiment of the present invention. The propulsion device is a one-axis type in which the power transmission paths 12 of the propulsion device shown in FIG. 1 are arranged in a row, whereas the propulsion device is a gear box type provided with a gear box 25 in the power transmission path 12. The main shaft 12b of the internal combustion engine 13 is connected to the propeller shaft 12a via the gearbox 25, and the main shaft 14a of the generator motor 14 is also connected to the propeller shaft 12a via the gearbox 25. In such a case, by incorporating the reversing mechanism into the gear box 25, the rotation of the main shaft 12b of the internal combustion engine 13 and the main shaft 14a of the generator motor 14 can be reversed and transmitted to the propeller shaft 12a. The gearbox 25 incorporates a planetary gear mechanism, and outputs one input power to the input side by splitting it into two shafts on the other side to be the output side, or outputs two input powers to the input side on one output side. It has the function of outputting by combining with the axis of.

Fig. 9 is a block diagram showing a ship propulsion device according to still another embodiment of the present invention. In addition to the generator 16 in the propulsion apparatus shown in FIG. 1, the propulsion apparatus is provided with a waste heat recovery apparatus 26 as a power supply source. The waste heat recovery apparatus 26 has a function of generating electric power by using the energy of the exhaust gas discharged from the internal combustion engine 13, and the exhaust gas, which is used by the waste heat recovery apparatus 26 and becomes low pressure and low temperature, is discharged to the outside.

In the waste heat recovery apparatus 26, a turbine is generated by rotating the turbine by the flow velocity of the exhaust gas and the pressure energy, and the boiler is heated by the thermal energy of the exhaust gas, and the steam turbine is driven by the steam turbine. There is a type. Thus, by using the energy of the exhaust gas of the internal combustion engine 13 as a power supply source, the fuel efficiency of an internal combustion engine can be improved more.

The propulsion apparatus shown in FIG. 9 has a rotation speed detector 27a for detecting the rotation speed Na of the propeller shaft 12a, and a rotation speed detector 27b for detecting the rotation speed Nb of the main shaft 12b. As shown in FIG. 7, the output torque Ta of the internal combustion engine 13 has a corresponding relationship with the rotation speed of the power transmission path 12, and the amount of change in the load torque applied to the propeller 11 by detecting the change in the rotation speed of the power transmission path 12. Can be obtained. In this way, determining the amount of change in the rotational speed of the power transmission path 12 means to obtain the amount of change in the load torque of the power transmission path 12. Therefore, in the case of performing propulsion control based on the rotation speed, if the rotation speed of the propeller shaft 12a falls, whether to reduce the amount of power generation, increase the assist torque of the generator motor 14, or change to the motor mode Is set. On the other hand, when the rotation speed increases, either one of increasing the amount of power generation, reducing the assist torque of the generator motor 14, or changing to the power generation mode is set. However, the fuel supply amount corresponding to the load torque and the map data of the rotation speed of the propeller 11 are stored in the ROM, and the detection signals from the rotation speed detectors 27a and 27b sent to the controller 20 correspond to the load torques Qa and Qb. Based on the fluctuation values of the rotational speeds of the propeller shaft 12a and the main shaft 12b, it is possible to control the power generation control mode and the assist control mode so that the rotational speed becomes the variation reference value Qs.

Also in the propulsion apparatus shown in FIG. 1 and FIG. 8, rotation speed detector 27a, 27b can be used instead of load torque detector 22a, 22b. Although FIG. 9 shows the same uniaxial propulsion apparatus as FIG. 1, it can be set as the type which has the same gearbox as FIG.

The present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention.

11 propeller
12 power transmission path
12a propeller shaft
12b spindle
13 internal combustion engine
14 generator motor
15 onboard electrical appliances
16 generator
17 powerline
18 power converter
19a capacitor
19b charging and discharging board
20 controller (control means, arithmetic means)
21a, 21b strain gauge
22a, 22b load torque detector
25 gearbox
26 Waste Heat Recovery Device
27a, 27b rpm detector

Claims (4)

As a propulsion device of a ship having a power transmission path connecting the propeller and the main shaft of the internal combustion engine to apply a propulsion to the ship,
A generator installed in a power transmission path and driven by an internal combustion engine to generate electric power,
A power supply unit to which power generated by the generator is supplied;
Load torque calculating means for calculating load torque applied to the power transmission path;
The load torque calculated by the load torque calculating means is compared with the change reference value of the load torque applied to the power transmission path. When the load torque is larger than the change reference value, the amount of power generated by the generator is reduced, and the load torque is smaller than the change reference value. In the case of having a control means for increasing the amount of power generated by the generator,
And said variation reference value is an average value per unit time of the load torque calculated by said load torque calculating means. As a propulsion device of a ship having a power transmission path connecting the propeller and the main shaft of the internal combustion engine to apply a propulsion to the ship,
An electric motor installed in the power transmission path to assist the propeller with power,
A power source for supplying electric motors,
Load torque calculating means for calculating load torque applied to the power transmission path;
The load torque calculated by the load torque calculating means is compared with the change reference value of the load torque applied to the power transmission path. When the load torque is larger than the change reference value, the assist output of the electric motor is increased, and the load torque is higher than the change reference value. Small case has control means for reducing the assist output of the electric motor,
And said variation reference value is an average value per unit time of the load torque calculated by said load torque calculating means. As a propulsion device of a ship having a power transmission path connecting the propeller and the main shaft of the internal combustion engine to apply a propulsion to the ship,
A generator motor installed in the power transmission path and driven by an internal combustion engine to generate electric power, and assisting propeller power,
A power supply unit to which power generated by the generator motor is supplied;
A power source for powering the generator motor,
Load torque calculating means for calculating load torque applied to the power transmission path;
The load torque calculated by the load torque calculating means is compared with the change reference value of the load torque applied to the power transmission path. When the load torque is larger than the change reference value, the generator motor is operated by the power from the power source to power the propeller. And control means for supplying electric power to the power supply unit by operating the generator motor by the internal combustion engine when the load torque is smaller than the variation reference value.
And said variation reference value is an average value per unit time of the load torque calculated by said load torque calculating means. The propulsion apparatus for a ship according to any one of claims 1 to 3, wherein the calculation of the load torque is calculated based on the amount of strain in the power transmission path or based on the rotation speed of the power transmission path. The propulsion device of the ship characterized in that.

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