WO2017141711A1

WO2017141711A1 - Electric propulsion device for ship, and propulsion force control device used in electric propulsion device for ship

Info

Publication number: WO2017141711A1
Application number: PCT/JP2017/003687
Authority: WO
Inventors: 学徳本; 集平藤本
Original assignee: ダイハツディーゼル株式会社
Priority date: 2016-02-16
Filing date: 2017-02-02
Publication date: 2017-08-24
Also published as: CN108698680B; CN108698680A; JP2017154510A; JP6284558B2

Abstract

The purpose of the present invention is to reduce energy loss occurring during navigation of a ship and to efficiently control propulsion force. Provided is an electric propulsion device (10), wherein in a first control mode, a governor control unit (35A) maintains the speed of an engine 33 at a first set speed N1 (750 min^-1), and a CPP control unit (35B) variably controls the pitch of a CPP (31) so as to meet a target pitch. Also, in a second control mode, the CPP control unit (35B) maintains the CPP (31) at a reference pitch αa, and the governor control unit (35A) controls the speed of the engine (33) within an engine speed range from the first set speed N1 to a second set speed N2 (900 min^-1)) so as to follow a characteristic curve (L1) for a ship.

Description

Electric propulsion device for ships, propulsion control device used for electric propulsion device for ships

The present invention relates to a marine vessel electric propulsion device for propelling a vessel by supplying an electric power to a variable pitch propeller, and a propulsion control device applied to the marine vessel electric propulsion device.

As a propulsion device for propelling a ship by rotationally driving a propeller provided on the ship, a marine electric propulsion device for obtaining the rotational driving force of a motor driven by the electric power of a generator connected to an internal combustion engine to rotate the propeller It has been known. For example, in Patent Document 1, a variable pitch propeller (CPP; hereinafter abbreviated as CPP) is connected to the output shaft of the motor, and the pitch (blade angle) of CPP is adjusted by adjusting the CPP. And an electric propulsion device for increasing and decreasing the propulsion of the ship.

An internal combustion engine such as a diesel engine used as a main engine of a ship has specifications such as rated output and the like in consideration of so-called marine characteristics of the ship. Generally, when the vertical axis is the engine output of the main engine and the horizontal axis is the ship speed, the relationship between the engine output and the ship speed is represented by a cubic curve. This cubic curve is widely known as a curve showing the above-mentioned marine characteristics (hereinafter sometimes referred to as a marine characteristic curve). That is, the marine property means that the engine output of the main engine is proportional to the cube of the speed of the ship. Since the propeller speed at the reference pitch and the ship speed are in a roughly proportional relationship, the marine characteristic curve has the vertical axis as the engine output of the main engine and the horizontal axis as the propeller speed (or the rotational speed of the main engine). In some cases, it may be represented by a cubic curve.

Here, an example of a marine characteristic curve for each pitch of the CPP when CPP is used as a ship propulsion device is shown in FIG. In FIG. 5, the vertical axis is the engine output of the main engine, and the horizontal axis is the propeller speed. Further, FIG. 5 shows the marine characteristic curve of each of the pitches α k (k = 1, 2,..., 11) that can be taken by CPP as a solid line. In general, it is desirable for vessels to operate efficiently in various sea conditions encountered during actual voyages. In addition, although the ship's life is long and the performance of the hull and the main engine declines due to the influence of aging and so on, the marine characteristics also change, but even if the ship's characteristics change, the ship's overall life is long It is desirable to be able to operate efficiently. In the example of FIG. 5, the propeller design of the CPP is a point T1 that satisfies the most fuel efficient condition (for example, the reference pitch is αa, the engine output is Pa, and the propeller rotational speed is Na) under operating conditions that the ship normally uses A marine characteristic curve L1 passing through the propeller design point T1 is indicated by a dotted line. Generally, in consideration of the engine output Pa and propeller rotational speed Na at the propeller design point T1, the reference pitch αa, the diameter, the wing shape, etc. of the CPP are designed so as to obtain a boat speed with good fuel efficiency.

2. Description of the Related Art Conventionally, as a method of controlling the speed of a ship by an electric propulsion device using CPP, an automatic speed control (ASC) that automatically controls the speed of the ship is known. When the actual ship speed changes with respect to the target speed due to a change in sea conditions, etc., the automatic ship speed control device either the propeller rotation speed (the rotation speed of the main engine) or the CPP pitch, or the propeller Control both the number of revolutions and the pitch so as to maintain the target speed. FIG. 6 is a diagram where FIG. 5 is overlaid with an isoship speed curve Vk (k = 1, 2,...). For example, when the actual ship speed is reduced to a ship speed Vs lower than the target speed V2 at the time of normal navigation, the propeller speed is kept constant and the pitch is changed to control the ship speed. The ship speed increases as shown in. On the other hand, in the case where the propeller rotation speed is controlled with the pitch kept constant, the boat speed increases along the marine characteristic curve as shown by arrow D2 in FIG.

JP 2007-131081 A

By the way, the iso-ship speed curve Vk shown in FIG. 6 is a curve connecting points of an engine output at which a predetermined boat speed is obtained and a propeller rotational speed, and draws a mortar-like curve. As shown in FIG. 6, the lowest part of each isospeed curve is the point where the fuel efficiency is the best and the engine output is the minimum. In FIG. 6, it can be seen that the marine characteristic curve L1 passing through the propeller design point T1 substantially matches the curve connecting the bottoms of the isoship speed curve Vk. As shown in FIG. 6, for example, when control is performed to maintain the propeller rotation speed constant (for example, Na) and change the pitch, the propeller speed Na is equal to the ship speed curve Vk at a low ship speed. The higher the boat speed, the lower the right. However, since the conventional automatic ship speed control device does not perform ship speed control according to the characteristics of the ship speed curve having different ship speeds, depending on the control method that can be taken, the fuel consumption at the time of ship speed control may be extreme. May be accompanied by Generally, since the engine output is proportional to the cube of the ship speed, if it is necessary to increase the engine output by a factor of 3 with respect to the increase in the ship speed, the fuel consumption is also approximately 3 for the increase in the ship speed. And the fuel efficiency may be significantly degraded.

The present invention has been made in view of the above-mentioned circumstances, and its object is to reduce the energy loss generated during the navigation of the ship and to perform the electric propulsion device for the ship capable of performing efficient propulsion control, and propulsion It is in providing a force control device.

(1) The present invention is an electric propulsion device for ships, which supplies electric power to a variable pitch propeller to promote the ship. The electric propulsion device for a ship includes a generator engine having a generator connected to an output shaft of an internal combustion engine, and an electric motor for rotationally driving by the AC power generated by the generator engine and supplying the electric power to the variable pitch propeller. And a control device for controlling the pitch of the variable pitch propeller and the rotational speed of the internal combustion engine so as to achieve a target value corresponding to the speed command signal based on a speed command signal input from a ship steering system. And.
The control device generates rotational speed of the internal combustion engine from a predetermined first set speed to a second set speed so as to generate AC power in a frequency band from a first predetermined frequency to a second frequency. It has a rotational speed control unit that controls within a speed range, and a pitch control unit that controls the pitch of the variable pitch propeller.
When the speed command signal is out of a predetermined reference range, the rotational speed control unit maintains the rotational speed of the internal combustion engine at either the first set speed or the second set speed, and the pitch The control unit controls the variable pitch propeller to a pitch according to the target value. Further, when the speed command signal is within the reference range, the pitch control unit maintains the pitch of the variable pitch propeller at a predetermined reference pitch corresponding to the speed range, and the rotation speed control unit The internal combustion engine is controlled to a rotational speed corresponding to the target value so as to follow a marine characteristic curve determined by the engine output of the internal combustion engine and the propeller rotational speed of the variable pitch propeller.

In general, ships are limited in speed in ports and on specific routes. Therefore, when the ship is navigating in the harbor, the ship's electric propulsion device rotationally drives the propeller in an area of low output in its output range. On the other hand, when sailing out of a port and sailing in the open sea, no speed limit is imposed on the ship. Therefore, after the ship leaves the outside port, the electric propulsion device for ship rotates the propeller under the condition where the output is relatively high in the output range and the fuel efficiency is the best. With the exception of vessels that work in harbors, such as tugs, many vessels travel at high power in the open ocean longer than they travel at low power in ports. Therefore, in general, the marine characteristics of a ship are determined on the basis of navigation in the open sea.
In the electric propulsion device for a ship according to the present invention, the rotational speed control unit of the control device controls the rotation of the internal combustion engine when the speed command signal from the steering device is out of the reference range in view of the use condition of the ship. The speed is maintained at either the first set speed or the second set speed, and the pitch control unit controls the variable pitch propeller at a pitch according to the target value. For example, when the speed command signal is lower than the lower limit value of the reference range, the rotational speed control unit maintains the rotational speed of the internal combustion engine at the first set speed, and the pitch control unit The variable pitch propeller is controlled to a pitch according to the target value. Further, when the speed command signal is higher than the upper limit value of the reference range, the rotational speed control unit maintains the rotational speed of the internal combustion engine at the second set speed, and the pitch control unit The variable pitch propeller is controlled to a pitch according to the target value.
In general, in the speed range lower than the first set speed, it is difficult to control the boat speed by the rotational speed of the internal combustion engine, and even if it can be controlled, the efficiency may be deteriorated. For this reason, in a speed range lower than the first set speed, controlling the pitch of the variable pitch propeller while maintaining the rotational speed at the first set speed enables efficient propulsion control with low energy loss. It has been realized.
On the other hand, when the speed command signal is within the reference range, the pitch control unit of the control device maintains the pitch of the variable pitch propeller at a predetermined reference pitch corresponding to the speed range. The rotational speed control unit controls the internal combustion engine to a rotational speed according to the target value so as to follow a marine characteristic curve determined by the engine output of the internal combustion engine and the propeller rotational speed of the variable pitch propeller. Within the above speed range, boat speed control by the rotational speed of the internal combustion engine is easy, and fuel efficiency is good. For this reason, within the speed range, efficient control of propulsion power with low energy loss is realized by variably controlling the rotational speed within the speed range while maintaining the variable pitch propeller at the reference pitch. .

(2) The frequency band is an allowable range of the power supply frequency supplied as a commercial power supply.

Thus, the power output from the power generation engine can be used as a commercial power source without frequency conversion. Therefore, power can be directly supplied from the power bus to the electrically driven load device used in the ship. That is, in the electric propulsion device for ships according to the present invention, power can be supplied to the load device without providing an inverter or the like that performs frequency conversion.

(3) Preferably, the first frequency is 50 Hz and the second frequency is 60 Hz.

In general, general-purpose electromagnetic contactors, circuit breakers such as circuit breakers, and electrical devices used in ships are standardly designed to be driven by AC power of 50 Hz to 60 Hz, and other frequencies (for example, 40 Hz) Driving with AC power is not guaranteed. Therefore, if the frequency band is 50 Hz to 60 Hz, it is possible to use an inexpensive and highly versatile electric circuit protector or an electric device.

(4) Moreover, it is preferable that the said marine characteristic curve approximates to the curve which ties the minimum of the iso-ship speed curve of the said ship.

(5) Further, according to the present invention, there is provided a generator engine having a generator connected to an output shaft of an internal combustion engine, and an electric motor which is driven to rotate by AC power generated by the generator engine and supplies electric power to a variable pitch propeller. , Applied to the electric propulsion device for a ship that propels the ship by supplying the electric power to the variable pitch propeller, and responds to the speed command signal based on the speed command signal input from the steering device of the ship. The propulsive force control device controls the pitch of the variable pitch propeller and the rotational speed of the internal combustion engine so as to achieve the target value.
The propulsion control device generates rotational speed of the internal combustion engine from a first predetermined speed to a second predetermined speed so as to generate AC power in a frequency band from a first predetermined frequency to a second frequency. And a pitch control unit for controlling the pitch of the variable pitch propeller.
When the speed command signal is out of a predetermined reference range, the rotational speed control unit maintains the rotational speed of the internal combustion engine at either the first set speed or the second set speed, and the pitch The control unit controls the variable pitch propeller to a pitch according to the target value. When the speed command signal is within the reference range, the pitch control unit maintains the pitch of the variable pitch propeller at a predetermined reference pitch corresponding to the speed range, and the rotational speed control unit is configured to: The internal combustion engine is controlled to a rotational speed according to the target value so as to follow a marine characteristic curve determined by the engine output of the internal combustion engine and the propeller rotational speed of the variable pitch propeller.

According to the present invention, in the electric propulsion device for ships, it is possible to perform efficient propulsion control by reducing the energy loss generated at the time of navigation of the ships.

FIG. 1 is a configuration diagram schematically showing a schematic configuration of an electric propulsion device according to an embodiment of the present invention. FIG. 2 is a graph showing a marine characteristic curve showing the relationship between the propeller rotational speed and the engine output in the electric propulsion device, and a ship speed curve showing the relationship between the propeller rotational speed, the engine output and the ship speed. FIG. 3 shows the correspondence among the boat speed command, control mode (control state), engine speed, generator frequency, motor speed, reduction ratio, propeller speed, pitch (blade angle) in the electric propulsion device. FIG. FIG. 4 is a flow chart showing an example of a procedure of propulsion control processing executed by the controller of the electric propulsion device. FIG. 5 is a graph showing a marine characteristic curve for explaining a conventional control method. FIG. 6 is a graph showing a marine characteristic curve and an isoship speed curve for explaining a conventional control method.

Hereinafter, embodiments of the present invention will be described with reference to the drawings as appropriate. The following embodiments are merely examples embodying the present invention, and do not limit the technical scope of the present invention.

The electric propulsion device 10 according to the embodiment of the present invention (an example of the electric propulsion device for a ship according to the present invention) comprises a variable pitch propeller 31 (hereinafter abbreviated as "CPP 31") which is a propulsion mechanism of a ship. It is rotated by the driving force to generate propulsion of the ship. As shown in FIG. 1, the electric propulsion device 10 includes a diesel engine 33 (an example of an internal combustion engine according to the present invention, hereinafter abbreviated as “engine 33”), and a generator 37 (an example of a generator according to the present invention). And an electric motor 39 (an example of the electric motor according to the present invention), a reduction gear 41, and a control device 35 (an example of a control device according to the present invention and a propulsion control apparatus) that integrally controls the operation of the electric propulsion device 10. And. The engine 33 and the generator 37 realize the power generation engine of the present invention.

Here, the electric propulsion device for ships according to the present invention is applicable to all ships promoted using CPP, and, for example, cargo ships such as container ships and tankers, passenger ships such as ferries and passenger ships, marine research ships, etc. It can be widely applied to vessels such as special vessels that carry out sea operations like this, navigation training vessels, and fishing boats used for fishing.

The engine 33 is used as a drive source for supplying rotational drive power to the generator 37 in a ship, and is, for example, a large diesel engine having an engine output of several hundred kW to several thousand kW. The engine 33 is provided with an electronic governor 34. The electronic governor 34 is controlled by a governor control unit 35A (an example of a rotational speed control unit of the present invention) included in the control device 35. Specifically, the electronic governor 34 changes the fuel rack position according to the signal input from the governor control unit 35A, and adjusts the injection amount of the fuel injection pump of the engine 33. Thereby, the rotational speed of the engine 33 is changed. Further, the engine 33 is provided with a speed sensor 24 for detecting the rotational speed of the engine 33. The velocity signal detected by the velocity sensor 24 is fed back to the controller 35. In the present embodiment, the engine 33 is illustrated as an example of the internal combustion engine, but the invention is not limited thereto. An internal combustion engine capable of outputting rotational driving force like a gas engine or a gas turbine instead of the engine 33 For example, various types of institutions are applicable. Further, the speed sensor 24 may detect the speed from the power generation frequency of the generator 37, for example.

The generator 37 is connected to the output shaft 48 of the engine 33. The input shaft of the generator 37 is directly connected to the output shaft of the engine 33 by a coupling (shaft joint) (not shown), and the rotational driving force of the output shaft 48 of the engine 33 is directly transmitted to the generator 37 as it is. Ru. The generator 37 receives the rotational driving force transmitted from the output shaft 48 of the engine 33 to rotate, and generates AC power of a frequency according to the rotational speed. Specifically, the generator 37 is an 8-pole 3-phase synchronous generator. In this embodiment, the engine with respect to the generator 37 of the number of poles is eight poles, the rotational speed of the engine 33 is 750min ^-1 (= first set speed N1) to 900 min ^-1 (= second set speed N2) The rotation is controlled by the controller 35 so as to be within the speed range.

Here, in general, there is a relationship of N = 120 f / P (min ⁻¹ ) between the shaft rotational speed N, the frequency f, and the number of poles P, so the engine speed range (750 min ⁻¹ to 900 min ⁻¹ ) By controlling the rotational speed of the engine 33, the generator 37 generates AC power within a frequency range of 50 Hz (= first frequency F1) to 60 Hz (= second frequency F2). Generate electricity and output. Specifically, the generator 37 when the rotational speed of the engine 33 is 750Min ^-1 is generating the AC power of 50 Hz, the AC power of the generator 37 is 60Hz when the rotational speed of the engine 33 is 900 min ^-1 Generate electricity.

The output side of the generator 37 is connected to a common power bus via the disconnector 54. Therefore, the alternating current power generated by the generator 37 flows into the power bus while the disconnector 54 is closed.

Electric power is supplied from the power bus to the electric motor 39 via a feeder 51 such as a power cable for transmission and distribution. In the feed line 51 extending from the power bus to the motor 39, a circuit breaker such as ACB (Air Circuit Breaker) or MCCB (Molded Case Circuit Breaker) in order to protect circuits and devices from excessive current. Is provided.

Further, a feed line 52 different from the feed line 51 is provided in parallel with the power bus. The feeder line 52 is for supplying power to the motor-driven load device 58 used on a ship. The load device 58 corresponds to, for example, various electric devices such as an electric pump, a motor-operated valve, a motor, a steering device, an alarm device, etc. used for a ship. Moreover, the load apparatus 58 corresponds to, for example, an electric apparatus used by being connected to an in-board power supply.

In the present embodiment, neither of the

feeders

51, 52 is provided with a frequency conversion device such as an inverter for converting the frequency of the AC power generated by the generator 37 into another frequency.

By the way, the switch and load device 58 connected to the power bus and the

feeders

51 and 52 are designed to match the power supply frequency of a commercial power supply. In Japan and other countries, 50 Hz and 60 Hz commercial power supplies are provided. That is, the allowable range of the power supply frequency supplied as commercial power is in the range of 50 Hz to 60 Hz. In the present embodiment, as described above, since the rotational speed of the engine 33 is controlled only between 750 min ^-1 and 900 min ^-1 , the fluctuation of the frequency of the generator 37 is 50 Hz to 60 Hz. That is, the generator 37 generates AC power in the frequency band of 50 Hz to 60 Hz. Therefore, an electric path protector such as a switch or a circuit breaker connected to the electric power bus or the

electric supply lines

51, 52, and the load device 58 which receives electric power supply from the electric supply line 52 operate with AC power of 50 Hz to 60 Hz. A versatile and inexpensive one designed as standard is applicable.

The motor 39 is rotationally driven by the input AC power of a predetermined frequency. Specifically, the motor 39 is a so-called squirrel cage three-phase induction motor using a six-pole cage rotor. The motor 39 is rotationally driven at a rotational speed according to the frequency of the input AC power when the AC power supplied through the power supply path 51 or the power supply path 52 is input. In this embodiment, the motor 39 is rotated at a rotational speed of 1000min ^-1 by AC power 50Hz is input, rotates at a rotational speed of 1200Min ^-1 by AC power 60Hz is input. In the induction motor, slippage occurs in the rotational speed of the rotor, so the actual rotational speed of the output shaft of the motor 39 is a speed obtained by subtracting the sliding speed from the above-mentioned rotational speed. In the following, for convenience of explanation, the rotational speed of the motor 39 will be described without considering the sliding speed.

The reduction gear 41 is connected to the output shaft of the motor 39 via a transmission gear (not shown). The reducer 41 reduces the rotational speed of the motor 39 at a predetermined reduction ratio and transmits the reduced speed to the propeller shaft 49 of the CPP 31. In the present embodiment, the reduction gear ratio of the reduction gear 41 is set to 7.69. Therefore, CPP31 is motor 39 rotates at a rotational speed of 130min ^-1 rotates at a rotation speed of 1000min ^-1, motor 39 is rotated at a rotational speed of 156min ^-1 rotates at a rotation speed of 1200min ^-1.

The CPP 31 is a propulsion unit that generates thrust in the direction of its rotation axis to obtain a propulsive force for propelling a ship. The CPP 31 is a screw propeller that can freely change the pitch of the blades 31A. By changing the pitch of the blades 31A, an arbitrary forward / backward propulsive force is generated while maintaining a constant rotational direction and a constant rotational speed. The CPP 31 includes a pitch change mechanism 31B. The plurality of blades 31A included in the CPP 31 are swingably attached to the propeller boss by the pitch inflection mechanism 31B, and the pitch (inclination angle) of the CPP 31 is changed, that is, inflected by the pitch inflection mechanism 31B. Can change the pitch. The pitch of the CPP 31 is inflected by the pitch in-segment mechanism 31B being controlled by a later-described CPP control unit 35B (an example of a pitch control unit of the present invention) included in the control device 35.

The control device 35 controls the electric propulsion device 10 to control the propulsion force applied to the ship by the electric propulsion device 10, and executes a propulsion force control process described later. Specifically, the control device 35 sets a target value corresponding to the speed command signal based on the speed command signal (ship speed command signal) input from the steering handle 15 (an example of the control device of the present invention) of the ship. The pitch of the CPP 31 and the rotational speed of the engine 33 are controlled to achieve (the target pitch or the target rotational speed). The control device 35 includes a microcomputer including a CPU, a ROM, a RAM, and the like, a main control board, and an arithmetic device such as a PLC. The propulsion control process is performed by the arithmetic device.

The control device 35 has a governor control unit 35A and a CPP control unit 35B. The governor control unit 35A and the CPP control unit 35B are functional units that are realized by the arithmetic device executing a control program in the ROM in the control device 35. The governor control unit 35A and the CPP control unit 35B may be realized by an integrated circuit such as an IC.

The control handle 35 is connected to the control device 35 by a signal line or the like. In addition to the scale of "NEUTRAL (neutral)", the steering handle 15 also has four scales "DEAD SLOW (fine speed)", "SLOW (low speed)" and "HALF (medium speed)" that indicate ship speed in both forward and reverse. "FULL (high speed)" is engraved. When the steering handle 15 is operated within the range of the scale, an electric signal (telegraph signal) corresponding to each boat speed is inputted from the potentiometer provided on the steering handle 15 to the control device 35 through the signal line. . This electrical signal is the speed command signal. The electric signal indicates a target value (target pitch or target number of revolutions) corresponding to the operation position of the steering handle 15, and the control device 35 controls the pitch of the CPP 31 and the engine 33 to achieve the target value. Control the rotational speed. The target value is stored in a storage device such as a RAM of the control device 35.

In the present embodiment, a current signal in the range of 4 mA to 20 mA is output as the electrical signal from the steering handle 15 to the control device 35. For example, when the steering wheel 15 is in the neutral position, a 4 mA signal is output. Further, when the steering handle 15 is operated from the neutral position to the forward side, a first electric signal (4 mA to 10 mA) for instructing control in a first control mode described later according to the operation position, which will be described later A second electric signal (10 mA to 18 mA) for instructing control in the second control mode is output, and a third electric signal (18 mA to 20 mA) for supporting control in a third control mode described later is output. Be done. Here, the range (range) of the second electric signal for instructing control in the second control mode is an example of a reference range of the present invention. In addition, the above-mentioned electric signal is a mere example, and the signal form is not restricted to what was mentioned above.

The governor control unit 35A predetermines the rotational speed of the engine 33 so that the generator 37 generates the AC power in the frequency band of the second frequency F2 (60 Hz) from the predetermined first frequency F1 (50 Hz). Control is performed within the engine speed range from the first set speed N1 (750 min ^-1 ) to the second set speed (900 min ^-1 ). The governor control unit 35 </ b> A controls the engine 33 such that the rotational speed corresponds to a first control mode to a third control mode described later. Specifically, the governor control unit 35A changes the fuel rack position of the electronic governor 34 provided in the engine 33, and adjusts the injection amount of the fuel injection pump according to each control mode, thereby the engine 33. Is controlled within the engine speed range from the first set speed N1 to the second set speed (900 min.sup.- ¹ ).

The CPP control unit 35B controls the blade 31A by driving the pitch change mechanism 31B so as to have an arbitrary pitch. In the present embodiment, the blades 31A of the CPP 31 can be varied from the pitch 0 to αmax. Here, the reference pitch of the blades 31A of the CPP 31 is αa. In the present embodiment, the CPP control unit 35B adjusts the blades 31A in the range of pitch 0 to αmax so that the pitch corresponds to a first control mode to a third control mode described later during forward control of the ship. In the reverse control of the ship, the CPP control unit 35B adjusts the blades 31A in the range of pitch -αmax to 0.

Here, in the first control mode, the rotational speed of the engine 33 is maintained at the first set speed N1 and is rotated, and the pitch of the CPP 31 is controlled from the speed command from the steering handle 15 within the range of 0 to αa. It is a control mode controlled to become a target value according to a signal. In this first control mode, the boat speed in the range indicated by arrow D1 in FIG. 2 can be controlled. Although the first set speed N1 can be arbitrarily determined, in the present embodiment, the first set speed N1 is a rotational speed at which the generator 37 can generate electric power of the first frequency F1 (750 min It is defined in ^-1 ). In the second control mode, the rotational speed of the engine 33 corresponds to the speed command signal according to the operation position of the steering handle 15 in the engine speed range from the first set speed N1 to the second set speed N2. This control mode is a control mode in which the pitch of CPP 31 is fixed to the reference pitch αa. In this second control mode, it is possible to control the boat speed in the range indicated by arrow D2 in FIG. The second set speed N2 is set to a rotational speed (900 min ^-1 ) used under the condition with the highest fuel efficiency under the operation condition that the ship usually uses during the voyage. Further, in the third control mode, the rotational speed of the engine 33 is maintained at the second set speed N2 and rotated, and the pitch of the CPP 31 is the speed command signal from the steering handle 15 within the range of αa to αmax. It is a control mode controlled to become a target value according to. In this third control mode, it is possible to control the boat speed in the range indicated by arrow D3 in FIG.

In the present embodiment, as shown in FIG. 2 and FIG. 3, in the first control mode, the controller 35 maintains the rotational speed of the engine 33 at the first set speed N 1 while keeping the control handle 15 in position. The pitch of CPP 31 is controlled to be the target pitch according to. In other words, in the first control mode, the governor control unit 35A controls the rotational speed of the engine 33 to be maintained at the first set speed N1, and the CPP control unit 35B sets the target according to the position of the steering handle 15. The pitch of CPP 31 is variably controlled to be the pitch. Here, FIG. 2 shows a marine characteristic curve L1 showing the relationship between the propeller rotational speed and the engine output in the electric propulsion device 10, and an isoship speed curve Vk showing the relationship between the propeller rotational speed, the engine output and the ship speed. FIG. In FIG. 2, the marine characteristic curve L1 approximates a curve connecting the minimum points of the iso-ship speed curve Vk of the ship. FIG. 3 is a view showing the correspondence among the target speed, the control state, the engine speed, the reduction ratio, the generator frequency, the propeller speed, and the blade angle (pitch) in the electric propulsion device 10. The marine characteristic curve L1, the iso-ship speed curve Vk, and the like in FIG. 2 are the same as in FIGS. 5 and 6, and thus the description thereof is omitted.

Further, in the second control mode, the control device 35 maintains the pitch of the CPP 31 at the reference pitch αa while the marine characteristic curve L1 determined by the engine output of the engine 33 and the rotational speed of the CPP 31 (see FIG. 2) The rotational speed of the engine 33 is controlled within the engine speed range (750 min.sup.- ¹ to 900 min.sup.- ¹ ) so that In other words, in the second control mode, the CPP control unit 35B controls the pitch of the CPP 31 so as to maintain the reference pitch αa, and the governor control unit 35A controls the target rotational speed according to the position of the steering handle 15. The rotational speed of the engine 33 is controlled within the engine speed range so as to follow the marine characteristic curve L1.

Further, in the third control mode, the control device 35 controls the pitch of the CPP 31 so as to achieve the target pitch according to the position of the steering handle 15, while maintaining the rotational speed of the engine 33 at the second set speed N2. . In other words, in the third control mode, the governor control unit 35A controls the rotational speed of the engine 33 to be maintained at the second set speed N2, and the CPP control unit 35B sets the target according to the position of the steering handle 15. The pitch of CPP 31 is controlled to be the pitch.

Hereinafter, with reference to the flowchart of FIG. 4, an example of the procedure of the propulsion control process executed by the control device 35 will be described. Here, S11, S12,... In FIG. 4 indicate the numbers of the processing procedures (steps). In the following description, although propulsive force control processing at the time of forward movement is described, the same processing is performed at the time of reverse movement.

The controller 35 controls the electronic governor 34 to maintain the rotational speed of the engine 33 at the first set speed N1 (750 min ^-1 ) when the steering handle 15 is in the neutral position. Further, the control device 35 changes the CPP 31 to the pitch 0. Hereinafter, the state controlled in this manner is referred to as a standby mode. In the standby mode, since the engine 33 is rotating at the first set speed N1, the generator 37 generates power of the first frequency F1 (50 Hz) that can be used as inboard power. Further, since the pitch of the CPP 31 is 0, the electric propulsion device 10 does not apply propulsion to the ship.

When in the standby mode, when the steering handle 15 is operated from the neutral position to forward, the control device 35 starts controlling the rotational speed of the engine 33 and controlling the pitch of the CPP 31 so as to advance the ship. .

In step S11, the control device 35 determines whether the current control mode is the first control mode. Such determination is performed based on the electric signal as the speed command signal output from the steering handle 15. For example, it is determined whether the speed command signal is the first electrical signal. If it is determined in step S11 that the control mode is the first control mode, the process proceeds to step S12.

In step S12, the governor control unit 35A of the control device 35 performs feedback based on a detection signal from the speed sensor 24 so as to maintain the rotational speed of the engine 33 at a predetermined 750 min ^-1 (first set speed N1). Perform control (constant speed control). At this time, the generator 37 generates AC power of a constant frequency 50 Hz (first frequency F1) corresponding to the constant rotation speed 750 mi, and receives the AC power, and the motor 39 rotates at 1000 min ⁻¹ , As a result, the CPP 31 rotates at a rotational speed of 133 min ^-1 .

Then, in the next step S13, the CPP control unit 35B of the control device 35 variably controls the pitch of the CPP 31 within the range from 0 to αa so as to achieve the target pitch according to the position of the steering handle 15.

If it is determined in step S11 that the first control mode is not set, the process proceeds to step S14. In step S14, the control device 35 determines whether the current control mode is the second control mode. Such determination is performed based on the electric signal as the speed command signal output from the steering handle 15. For example, it is determined whether the speed command signal is the second electrical signal. If it is determined in step S15 that the control mode is the second control mode, the process proceeds to step S15.

In step S15, the CPP control unit 35B of the control device 35 controls the pitch indirection mechanism 31B such that the pitch of the CPP 31 maintains the reference pitch αa.

Then, in the next step S16, the governor control unit 35A of the control device 35 controls the electronic governor 34 so as to achieve the target rotational speed according to the position of the steering handle 15, and the rotational speed of the engine 33 Control within the range of 900 min ^-1 . Thus, the generator 37 generates AC power of a frequency corresponding to the rotational speed of the engine 33, and the AC power is supplied to the motor 39. Thus, in a state maintaining the reference pitch .alpha.a, rotational speed of CPP31 is controlled within a range of ^130min ^-1 ~ ^156min -1.

If it is determined in step S14 that the second control mode is not in effect, the process proceeds to step S17. In step S17, the control device 35 determines that the current control mode is the third control mode, and the governor control unit 35A of the control device 35 sets the rotational speed of the engine 33 to 900 min ^-1 (predetermined). The speed is increased to the second set speed N2), and feedback control (constant speed control) is performed based on the detection signal from the speed sensor 24 so as to maintain 900 min ⁻¹ . At this time, the generator 37 generates AC power of a constant frequency 60 Hz (second frequency F2) corresponding to the constant rotation speed 900 mi, and receives the AC power, and the motor 39 rotates at 1200 min ⁻¹ , Thus, the CPP 31 rotates at a rotational speed of 156 min ^-1 .

Then, in the next step S18, the CPP control unit 35B of the control device 35 variably controls the pitch of the CPP 31 within the range from αa to αmax so as to achieve the target pitch according to the position of the steering handle 15.

When the steering handle 15 is returned to the neutral position after steps S13, S16, and S18, a series of thrust control processing ends, and when the control handle 15 is not returned to the neutral position, the processing from step S11 is repeated (S19) ).

Thus, in the electric propulsion device 10 of the present embodiment, the governor control unit 35A maintains the rotational speed of the engine 33 at the first set speed N1 (750 min ^-1 ) in the first control mode, and the CPP control unit 35B. Since the pitch of CPP 31 is variably controlled to be the target pitch, energy loss during navigation of the ship can be suppressed and efficiency can be improved in the first control mode, which is a low speed control area.

In the second control mode, which is the medium speed control region, the CPP control unit 35B maintains the reference pitch αa, and the governor control unit 35A follows the marine characteristic curve L1 within the engine speed range. Is variably controlled to achieve the target rotational speed. For this reason, in the second control mode, by controlling the rotational speed of the engine 33 in the engine speed range while maintaining the pitch of the CPP 31 at the reference pitch αa, efficient propulsion control with low energy loss is realized. It is possible to realize.

Further, in the third control mode, which is the high speed region, the governor control unit 35A maintains the rotational speed of the engine 33 at the second set speed N2 (900 min ^-1 ), and the CPP control unit 35B performs the CPP 31 pitch Variable control is performed to achieve the target pitch. As described above, the generator 37 does not generate power outside the range of 50 Hz to 60 Hz in all control modes of the first control mode, the second control mode, and the third control mode. Therefore, the power generated by the generator 37 can be directly supplied to the load device 58 used on board. That is, in the electric propulsion device 10, the generated power can be supplied to the load device 58 without providing an inverter or the like that performs frequency conversion.

Further, in the electric propulsion device 10, the reduction ratio of the reduction gear 41 can be reduced as compared with the conventional configuration, and the reduction gear 41 can be miniaturized. As a result, the gear loss of the reduction gear is reduced, the reduction efficiency of the reduction gear 41 is improved, and the efficiency of the electric propulsion device 10 is improved.

In the above embodiment, the electric propulsion device 10 configured by one engine 33, one generator 37, one motor 39, and one CPP 31 is illustrated, but the present invention is not limited to this configuration. It is not limited. The present invention can also be applied to a marine electric propulsion apparatus configured to rotationally drive the motor 39 using alternating current power generated by a plurality of engines 33 and generators 37 by a power generation engine.

In the above embodiments, configurations for rotating the engine 33 in the range of ^750min ^-1 ~ ^900min -1, configured to rotate the CPP31 in the range of ^130min ^-1 ~ ^156min -1, has been illustrated, the engine 33 and The control range of the rotational speed of each CPP 31 is merely an example, and can be set to an arbitrary range. For example, as the control range of the rotational speed of the engine ^33, and the range of 600min ^-1 ~ 750min ^-1, may be applied to a range of 1000min ^-1 ~ 1200min -1.

Claims

An electric propulsion device for ships, which supplies electric power to a variable pitch propeller to promote the ship,
A power generation engine having a generator connected to an output shaft of the internal combustion engine;
An electric motor that is rotationally driven by AC power generated by the power generation engine to supply the electric power to the variable pitch propeller;
A control device for controlling the pitch of the variable pitch propeller and the rotational speed of the internal combustion engine so as to obtain a target value corresponding to the speed command signal based on a speed command signal input from a ship steering system; Equipped
The controller is
The rotational speed of the internal combustion engine is controlled within a speed range from a predetermined first set speed to a second set speed so as to generate AC power in a frequency band from a first predetermined frequency to a second frequency. Rotation speed control unit,
And a pitch control unit that controls the pitch of the variable pitch propeller.
When the speed command signal is out of a predetermined reference range, the rotational speed control unit maintains the rotational speed of the internal combustion engine at either the first set speed or the second set speed, and the pitch The control unit controls the variable pitch propeller to a pitch according to the target value,
When the speed command signal is within the reference range, the pitch control unit maintains the pitch of the variable pitch propeller at a predetermined reference pitch corresponding to the speed range, and the rotational speed control unit is configured to: The marine vessel electric propulsion device controls the internal combustion engine to have a rotational speed according to the target value along a marine characteristic curve determined by an engine output of the internal combustion engine and a propeller rotational speed of the variable pitch propeller.
The marine vessel electric propulsion device according to claim 1, wherein the frequency band is an allowable range of a power supply frequency supplied as a commercial power supply.
The electric propulsion system for a vessel according to claim 2, wherein the first frequency is 50 Hz and the second frequency is 60 Hz.
The marine vessel electric propulsion device according to claim 1, wherein the marine characteristic curve approximates a curve connecting minimum points of iso-velocity curves of the marine vessel.
A generator engine having a generator connected to an output shaft of the internal combustion engine; and an electric motor rotationally driven by the AC power generated by the generator engine to supply an electric power to the variable pitch propeller; The present invention is applied to a marine electric propulsion device for propelling a ship by supplying it to a variable pitch propeller, and based on a speed command signal input from a ship steering device, the target value corresponding to the speed command signal is obtained. A propulsion control device for controlling a pitch of a variable pitch propeller and a rotational speed of the internal combustion engine,
The rotational speed of the internal combustion engine is controlled within a speed range from a predetermined first set speed to a second set speed so as to generate AC power in a frequency band from a first predetermined frequency to a second frequency. Rotation speed control unit,
And a pitch control unit that controls the pitch of the variable pitch propeller.
When the speed command signal is out of a predetermined reference range, the rotational speed control unit maintains the rotational speed of the internal combustion engine at either the first set speed or the second set speed, and the pitch The control unit controls the variable pitch propeller to a pitch according to the target value,
When the speed command signal is within the reference range, the pitch control unit maintains the pitch of the variable pitch propeller at a predetermined reference pitch corresponding to the speed range, and the rotational speed control unit is configured to: A propulsion control device controls the internal combustion engine to a rotational speed according to the target value so as to follow a marine characteristic curve determined by an engine output of the internal combustion engine and a propeller rotational speed of the variable pitch propeller.