JP2007326391A - Marine vessel propulsion system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a marine vessel propulsion system high in energy saving efficiency in optimal equipment constitution and capable of corresponding to various driving status. <P>SOLUTION: It is possible to collect energy from exhaust gas without setting an exhaust gas economizer and a steam turbine as a generator to generate electric power by collecting excess exhaust energy on a supercharger and the generator is connected to an inboard electric power source system on this marine vessel propulsion system providing a shaft power generating set on a propeller shaft by connecting a main engine with the supercharger and a propeller to each other by the propeller shaft. Consequently, it is possible to provide a high energy saving effect by constitution with less of the equipment in addition to an energy saving effect of the shaft power generating set. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a ship propulsion system capable of saving energy of a ship.

Conventional ship propulsion systems are disclosed in Patent Documents 1 and 2, for example. In Patent Document 1, a first generator motor is connected to a rotating shaft of a supercharger operated by exhaust gas from a main engine, a second generator motor is connected to a propulsion shaft of the main machine via a speed reducer, and first and second A configuration in which generator motors are electrically connected to each other has been proposed. Patent Document 2 proposes a configuration in which a propulsion heating turbine is operated with exhaust gas economizer superheated steam and propulsion is supplied via a reduction gear.
Japanese Examined Patent Publication No. 63-5565 Japanese Patent Publication No. 61-55602

Usually, to save energy on ships, a method of attaching a shaft generator to the main engine, a method of generating steam with an exhaust gas economizer to drive a turbine and generating or propelling power, or a generator attached to a turbocharger of the main engine to generate electricity A method has been proposed.
However, none of these methods has been widely used in terms of energy saving effect due to high cost due to an increase in installation equipment, installation space, and maintenance costs.

  As shown in FIG. 4, the conventional marine vessel propulsion system has a first generator motor 51 installed in the supercharger 4 of the main engine 1, and is installed on the first generator motor 51 and the propulsion shaft 3 via a speed reducer 6. The second generator motor 52 is electrically connected. When the main machine 1 rotates the propeller 2 with a low load, the first generator motor 51 is driven by the power generated by the second generator motor 52 to energize the supercharger 4, and the main machine 1 rotates the propeller 2 at rated operation. In some cases, the second generator motor 52 is driven by the power generated by the first generator motor 51 and the main motor 1 is energized (see Patent Document 1). However, the turbocharger is generally operated at tens of thousands of revolutions. Since the main engine speed is operated at a low speed of several tens of revolutions, a multi-stage reduction gear is required to match the rotation speed, resulting in an increase in installation space and maintenance costs, and a decrease in reliability. .

  In another conventional marine vessel propulsion system, as shown in FIG. 5, the propulsion turbine 9 is driven by surplus steam generated by the exhaust gas economizer 7 and the propulsion force is applied to the propeller 2 via the speed reducer 6. However, since the rotational speed of the main machine 1 is operated at a low speed of several tens of revolutions, a multistage reduction gear is required to match the rotational speed, resulting in an increase in installation space and maintenance cost. It will be. Further, when the rotational speed of the main engine 1 changes, it is difficult to finely control the amount of steam generated by the exhaust gas economizer 7, it is difficult to follow the rotational speed of the propulsion boosting turbine 9, and a large load is applied to the speed reducer 6. In some cases, reliability is reduced. In addition, 5 is a generator and 8 is a steam turbine.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a marine vessel propulsion system capable of responding to various driving situations with high energy saving efficiency with an optimum device configuration.

  In order to achieve the above object, a first aspect of the present invention provides a marine vessel propulsion system in which a main engine with a supercharger and a propeller are connected by a propulsion shaft, and a shaft power generator is provided on the propulsion shaft. A generator for recovering surplus exhaust energy and generating electricity is attached to the machine, and the generator is connected to an inboard power supply system.

  According to the first aspect of the present invention, in addition to the energy saving effect of the shaft power generator, energy can be recovered from the exhaust gas without installing an exhaust gas economizer or a steam turbine, so that a higher energy saving effect can be obtained with a small equipment configuration.

  According to a second aspect of the present invention, in the marine vessel propulsion system according to the first aspect, the generator attached to the supercharger of the main engine is a high-speed generator directly connected to the supercharger shaft, and the high-speed generator has a frequency converter. It is characterized by being connected to an inboard power supply system.

  According to the second aspect of the present invention, since the high speed generator is directly connected on the coaxial of the main turbocharger, a reduction gear is not required between the supercharger and the generator. The maintenance cost can be reduced.

  According to a third aspect of the present invention, in the marine vessel propulsion system according to the first or second aspect, the generator attached to the supercharger of the main engine is either or both of the shaft power generator and the inboard power system when the main engine is activated. It can be driven as a motor by receiving power supply from either of them.

  According to the invention described in claim 3, supercharging is performed by driving the generator as a motor in a state where the exhaust gas energy at the time of starting the main engine is small or at a low load and the supercharging of the supercharger is insufficient. Since it can be energized, the amount of air blown by the auxiliary blower that is normally performed can be reduced, and the number and capacity of auxiliary blowers can be reduced. Further, in the case of a high-speed generator directly connected to a supercharger, the rotation frequency can be varied by a frequency converter, so that it is possible to easily follow changes in the required supercharging amount and supercharging pressure of the main engine.

  According to a fourth aspect of the present invention, in the marine vessel propulsion system according to any one of the first to third aspects, the power generation output of the shaft power generation device and the power generation output of the power generator attached to the supercharger are loaded on the load of the main engine. It can be adjusted according to the situation.

  According to the invention described in claim 4, when thrust or supercharge is required during stormy weather, etc., by adjusting the power generation output of the shaft power generator and the power generation output of the generator installed in the supercharger, The output of the propulsion shaft can be increased. Further, the supercharging amount and supercharging pressure of the supercharger can be varied, and stable navigation can be performed.

  According to a fifth aspect of the present invention, in the marine vessel propulsion system according to any one of the first to fourth aspects, the shaft power generator is configured to generate power output obtained by collecting surplus exhaust energy of the supercharger and the power generation output. It is characterized in that power is supplied from both or one of the inboard power supply systems via the frequency converter and is driven as a motor for propulsion.

  According to the fifth aspect of the present invention, when a propulsive force is required during stormy weather or the like, the shaft generator can be driven as a motor to energize the main engine, so that the output of the propulsion shaft can be increased, It is not necessary to add a speed reducer, and the equipment installation space and maintenance cost can be reduced. Further, since the rotational frequency of the shaft generator can be varied by the frequency converter, it is possible to easily follow changes in the rotational frequency of the main engine, so that stable navigation is possible.

According to a sixth aspect of the present invention, in the ship propulsion system according to the third to fifth aspects, the ship propulsion power supply system and the inboard power supply system can be separated.
According to the sixth aspect of the invention, since the propulsion power supply system and the shipboard power supply system can be arbitrarily separated, the shipboard power supply is stable even when the output fluctuation of the generator attached to the shaft generator or the turbocharger is large. Can be kept.

  According to the present invention, it is possible to provide a marine vessel propulsion system that is highly energy-saving with an optimal device configuration and can cope with various driving situations.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of a first embodiment of the present invention.
As shown in the figure, in the marine vessel propulsion system according to the present embodiment, the main engine 1 and the propeller 2 are connected by a propulsion shaft 3, and a shaft power generator 10 is installed on the propulsion shaft 3. The main machine 1 is provided with a supercharger 4 that is driven by main machine exhaust gas, and the supercharger 4 is provided with a generator 5 via a speed reducer 6. The power generated by the shaft power generator 10 is connected to the frequency converter 11 so as to be converted into an inboard frequency and supplied to the inboard power system 14 through the circuit breaker 13. The synchronous phase adjuster 12 adjusts the output voltage and frequency of the shaft generator 10.

  Since the ship propulsion system of the present embodiment is configured as described above, in addition to the energy saving effect of the shaft power generator, energy can be recovered from the exhaust gas without installing an exhaust gas economizer or a steam turbine, thereby achieving high energy savings. An effect is obtained.

FIG. 2 is a block diagram of the second embodiment of the present invention.
As shown in the figure, the ship propulsion system according to this embodiment differs from the first embodiment in FIG. 1 in that a high speed generator 17 is directly connected to the supercharger 4, and the generated power is generated by a frequency converter 18. The point is that it is converted to the inboard frequency and connected to the inboard power supply system 14 through the circuit breaker 13, and the other configuration is the same as that of the first embodiment, and the description thereof is omitted.

  Since the present embodiment is configured as described above, in addition to the same effects as those of the first embodiment, a reduction gear is not required between the supercharger and the high-speed rotating machine, and a reduction in equipment installation space and a reduction gear are achieved. The maintenance cost can be reduced.

  In FIG. 1 or FIG. 2, the third embodiment of the present invention is the power generated by the shaft power generator 10 in a state where the amount of exhaust gas is small at the time of starting the main engine or at a low load and the supercharging by the supercharger is not sufficient. Electric power from both or one of the inboard power supply systems 14 is supplied to the generator 5 or the high-speed generator 17, motored, and the supercharger 4 is energized. When supplying power to the high-speed generator 17, the frequency converter 18 converts the power into a desired rotation frequency and energizes the supercharger 4.

  Since the present embodiment is configured as described above, power generation installed in the supercharger when the exhaust gas energy at the time of starting the main engine is small or when the supercharger is insufficient at low load. Supercharging can be boosted by driving the machine as a motor. Accordingly, it is possible to reduce the amount of air blown by the auxiliary blower that is normally performed, and to reduce the number and capacity of the auxiliary blowers. Further, when motoring a high-speed generator, the rotation frequency can be varied by the frequency converter, so that it is possible to easily follow changes in the required supercharging amount and supercharging pressure of the main engine.

FIG. 3 is a block diagram of the fourth embodiment of the present invention.
In the figure, the ship propulsion system according to this embodiment differs from the first embodiment of FIG. 1 in that the frequency converter 11 of the shaft generator 10 and the frequency converter 18 of the high-speed generator 17 are This is because the amount of power generation is controlled so as to always obtain an optimum output based on the signal, and the other configuration is the same as that of the first embodiment, and the description thereof will be omitted.

  Since this embodiment is configured as described above, when a propulsive force or supercharging is required during stormy weather, the power generation output of the shaft power generator and the power generation output of the generator installed in the supercharger are By adjusting, the output of the propulsion shaft, or the supercharging amount and supercharging pressure of the supercharger can be varied, and stable navigation can be achieved.

  In the fifth embodiment of the present invention, in FIG. 1 or FIG. 2, the power generated by the generator 5 or the high-speed generator 17 and / or the inboard power system 14 are converted into the main engine by the frequency converter 11. Power is converted into a rotational frequency, the shaft generator 10 is motored, and the main machine 1 is energized.

  Since the present embodiment is configured as described above, when a propulsive force is required during stormy weather, etc., the shaft generator can be driven as a motor and the main engine can be energized. It is possible to reduce the equipment installation space and maintenance costs by eliminating the need for a reduction gear to support the main engine. Further, since the rotational frequency of the shaft power generator can be varied by the frequency converter, it is possible to easily follow the rotational frequency change of the main engine, so that stable navigation is possible.

  In FIG. 1 to FIG. 3, the sixth embodiment of the present invention opens the circuit breaker 13 and disconnects the propulsion power supply system of the shaft generator 10 and the generator 5 or the high-speed generator 17 from the inboard power supply system 14.

  Since the present embodiment is configured as described above, even when the output fluctuation of the generator attached to the shaft generator or the supercharger is large, the in-board power supply can maintain a stable state.

The block diagram of the 1st Embodiment of this invention. The block diagram of the 2nd Embodiment of this invention. The block diagram of the 4th Embodiment of this invention. The block diagram of the conventional ship propulsion system. The block diagram of the other conventional ship propulsion system.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Main machine, 2 ... Propeller, 3 ... Propulsion shaft, 4 ... Supercharger, 5, 51, 52 ... Generator, 6 ... Reduction gear, 7 ... Exhaust gas economizer, 8 ... Power generation turbine, 9 ... Propulsion support turbine, DESCRIPTION OF SYMBOLS 10 ... Shaft generator, 11 ... Frequency converter, 12 ... Synchronous phase adjuster, 13 ... Circuit breaker, 14 ... Inboard power system, 15 ... Main generator, 16 ... Inboard load, 17 ... High speed generator, 18 ... Frequency converter Device, 19 ... Main machine sensor.

Claims (6)

  In a marine vessel propulsion system in which a main unit with a supercharger and a propeller are connected by a propulsion shaft, and a shaft power generator is provided on the propulsion shaft, a generator that collects surplus exhaust energy and generates power is attached to the supercharger of the main unit, A ship propulsion system, wherein the generator is connected to an inboard power system.   2. The ship propulsion system according to claim 1, wherein the generator attached to the supercharger of the main engine is a high-speed generator directly connected to a supercharger shaft, and the high-speed generator is connected to an in-board power supply system via a frequency converter. Ship propulsion system characterized by that.   The ship propulsion system according to claim 1 or 2, wherein the generator attached to the supercharger of the main engine is supplied with electric power from both or one of the shaft power generator and the inboard power system when the main engine is activated. A marine vessel propulsion system that can be driven as a motor.   The ship propulsion system according to any one of claims 1 to 3, wherein the power generation output of the shaft power generation device and the power generation output of a generator attached to the supercharger can be adjusted according to a load situation of the main engine. Ship propulsion system characterized by that.   The ship propulsion system according to any one of claims 1 to 4, wherein the shaft power generator is configured to generate power output obtained by recovering surplus exhaust energy of the supercharger and / or the inboard power system. A ship propulsion system that receives power supply from either side through the frequency converter and drives as a motor for propulsion.   6. A marine vessel propulsion system according to claim 3, wherein the marine vessel propulsion power system and the inboard power system can be separated.

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