JP2007174799A - Electric propulsion system for ships - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric propulsion system for ships wherein two motors can be controlled in balance for more efficient operation. <P>SOLUTION: The electric propulsion system for ships includes: two contra-rotating propellers that are rotated in opposite directions to each other; and the two motors that respectively rotate the propellers. The electric propulsion system is so constructed that a torque standard is computed from a speed standard that provides a standard for controlling the rotational speed of each motor and the motors are independently controlled. The propulsion system is provided with a torque balance controlling means that corrects any of speed standards so that the motors become equal in torque based on the difference between two torque standards. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a marine electric propulsion apparatus that is an electric control system used for ships and the like.

  In general, a contra-rotating propeller is used as a propeller for ship propulsion from the viewpoint of efficiency. The contra-rotating propeller is composed of a front propeller disposed on the propulsion direction side and a rear propeller disposed on the opposite side of the propulsion direction. The front propeller and the rear propeller are arranged on the same axis so that the rotational flow generated in the front propeller Can be recovered with a post-propeller, and high efficiency can be obtained.

In the ship drive system using the counter rotating propeller, the power obtained by a prime mover such as a conventional diesel engine is given a fixed speed ratio by a coupling gear to drive the counter rotating propeller. However, this method has a drawback that it cannot operate most efficiently over the entire ship speed range. Therefore, as a method for solving this, there is a method of driving an electric motor with a power converter. As a method of driving the counter rotating propeller with the power converter, the speed of the first propeller is controlled, and the second propeller is converted into a signal such as a current or torque of the motor driven by the first power converter. Based on this, a configuration for controlling current or torque has been proposed (see, for example, Patent Document 1). Moreover, in order to control an alternating current motor, the method of estimating the rotational speed of an alternating current motor is disclosed (for example, refer nonpatent literature 1).
Japanese Patent Laid-Open No. 06-165585 Takayoshi Nakano, “Vector control of AC motor”, published by Nikkan Kogyo Shimbun, March 29, 1996 91

  However, in the method disclosed in the prior art document, for example, when the load suddenly decreases, for example, when the propeller goes out to sea, the speed of the motor driving the second propeller increases abnormally, so that Overvoltage and overspeed may be caused. Moreover, since this system controls the electric motor that drives the second propeller with current or torque, the rotational speed of the two propellers is not always efficient.

  Accordingly, an object of the present invention is to propose a marine electric propulsion device that can control two electric motors in a balanced manner and can operate more efficiently.

  A marine electric propulsion apparatus according to an aspect of the present invention controls a counter-rotating propeller in which two propellers rotate in opposite directions, two electric motors that rotate the propellers, and a rotation speed of the electric motors. A speed reference serving as a reference for performing the operation, and two torque reference calculating means for calculating a torque reference for controlling the torque of each electric motor, and based on the speed reference, In each of the marine electric propulsion devices to be controlled, any one of the torque reference calculation means so that the torques of the electric motors are equal based on the torque references calculated by the torque reference calculation means. And a torque balance control means for correcting the speed reference inputted to the engine.

  According to the present invention, it is possible to propose a marine electric propulsion device that can control two electric motors in a balanced manner and can operate more efficiently.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, the contra-rotating propeller common to each embodiment will be described with reference to FIG.

  The contra-rotating propeller includes a front propeller 1 arranged on the propulsion direction side, a rear propeller 2 arranged on the opposite side to the propulsion direction, an electric motor 3a provided with the front propeller 1, and a rear propeller 2. And an electric motor 3b. Moreover, as for the electric motor 3a and the electric motor 3b, both rotating shafts are arrange | positioned coaxially.

  With the above-described configuration, the counter-rotating propeller can recover the energy of the rotating flow generated by the front propeller 1 by the rear propeller 2, and high efficiency can be obtained.

(First embodiment)
With reference to FIG. 1, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated. The same parts as those in FIG. 12 are denoted by the same reference numerals and detailed description thereof is omitted, and different parts are mainly described here. In the following embodiments, the same description is omitted.

  This apparatus includes a front propeller 1, a rear propeller 2, motors 3a and 3b, power converters 4a and 4b, speed detectors 5a and 5b, current detectors 6a and 6b, speed controllers 7a and 7b, and a current reference calculator 8a. , 8b, current controllers 9a, 9b, torque balance controller 10, limiter 17, subtractors 31a, 31b, 32a, 32b, 34b, adder 33b, and speed reference calculator 40a.

  This device is a device that performs control during normal rotation of the contra-rotating propeller.

  The front propeller 1, the rear propeller 2, and the electric motors 3a and 3b constitute the above-described counter rotating propeller.

  First, a configuration for controlling the front propeller 1 will be described.

  The configuration for controlling the front propeller 1 is through a speed reference calculator 40a, a subtractor 31a, a speed controller 7a, a current reference calculator 8a, a subtractor 32a, a current controller 9a, a power converter 4a, and an electric motor 3a in this order. So connected. The front propeller 1 is provided in the electric motor 3a. The speed detector 5a is provided so that the rotational speed of the front propeller 1 can be detected. The current detector 6a is provided on the output side of the power converter 4a.

  The speed reference calculator 40a calculates a speed reference L11a that is a reference for controlling the rotation speed of the electric motor 3a. The speed reference calculator 40a inputs the calculated speed reference L11a to the subtractor 31a.

  The speed detector 5a detects the rotational speed of the electric motor 3a. The speed detector 5a inputs the detected rotation speed to the subtractor 31a as a speed feedback L12a.

  The subtractor 31a calculates a difference obtained by subtracting the speed feedback L12a input from the speed detector 5a from the speed reference L11a input from the speed reference calculator 40a. The subtractor 31a inputs the calculated difference to the speed controller 7a.

  The speed controller 7a calculates a torque reference L13a serving as a reference for controlling the torque of the electric motor 3a based on the difference input from the subtractor 31a. The speed controller 7a inputs the calculated torque reference L13a to the current reference calculator 8a.

  Based on the torque reference L13a input from the speed controller 7a, the current reference calculator 8a calculates a current reference L14a that serves as a reference for controlling the alternating current output from the power converter 4a. The current reference calculator 8a inputs the calculated current reference L14a to the subtractor 32a.

  The current detector 6a detects the alternating current output from the power converter 4a. The current detector 6a inputs the detected alternating current as a current feedback L15a to the subtractor 32a.

  The subtractor 32a calculates a difference obtained by subtracting the current feedback L15a input from the current detector 6 from the current reference L14a input from the current reference calculator 8a. The subtractor 32a inputs the calculated difference to the current controller 9a.

  Based on the difference input from the subtractor 32a, the current controller 9a calculates a voltage reference L16a that serves as a reference for controlling the AC voltage output from the power converter 4a. The current controller 9a inputs the calculated voltage reference L16a to the power converter 4a.

  The power converter 4a controls driving of the electric motor 3a based on the input voltage reference L16a.

  The front propeller 1 rotates in accordance with the driving of the electric motor 3a.

  With the above-described configuration, the rotation of the front propeller 1 is controlled based on the speed reference L11a.

  Next, a configuration for controlling the rear propeller 2 will be described.

  The configuration for controlling the rear propeller 2 includes a speed reference calculator 40a, a subtractor 31b, a speed controller 7b, a current reference calculator 8b, a subtractor 32b, a current controller 9b, a power converter 4b, an electric motor 3b, and a rear propeller 2. , A speed detector 5b, a current detector 6b, a subtractor 34b, a torque balance controller 10, and a limiter 17 adder 33b.

  Among the configurations for controlling the rear propeller 2, the subtractor 31b includes a speed controller 7b, a current reference calculator 8b, a subtractor 32b, a current controller 9b, a power converter 4b, an electric motor 3b, a rear propeller 2, and a speed detector. 5b, current detector 6b, subtractor 31a, speed controller 7a, current reference calculator 8a, subtractor 32a, current controller 9a, power converter 4a, motor 3a, front, The configuration is the same so as to correspond to the propeller 1, the speed detector 5a, and the current detector 6a, respectively, and the description thereof is omitted.

  Similarly, in the control of the rear propeller 2, the speed reference L11b, the speed feedback L12b, the torque reference L13b, the current reference L14b, the current feedback L15b, and the voltage reference L16b are the speed reference L11a, the speed feedback L12a, The torque reference L13a, the current reference L14a, the current feedback L15a, and the voltage reference L16a respectively correspond to each other and will not be described.

  The subtractor 34b has the input side connected to the output side of the speed controllers 7a and 7b, and the output side connected to the input side of the torque balance controller 10. The adder 33b is provided between the speed reference calculator 40a and the subtractor 31b. In the torque balance controller 10, the input side of the adder 33 b is connected to the output side via the limiter 17.

  The subtractor 34b receives the torque reference L13a calculated by the speed controller 7a and the torque reference L13b calculated by the speed controller 7b. The subtractor 34b calculates a difference obtained by subtracting the torque reference L13b from the torque reference L13a. The subtractor 34 b inputs the calculated difference to the torque balance controller 10.

  The torque balance controller 10 inputs an output signal based on the difference input from the subtractor 34 b to the adder 33 b via the limiter 17.

  The limiter 17 limits the output signal of the torque balance control 10 when the difference input from the subtractor 34b becomes extremely large. Thereby, the limiter 17 prevents the speed reference L11b of the electric motor 3b from becoming overspeed.

  The adder 33b receives the speed reference L11a from the speed reference calculator 40a. The adder 33b adds a value based on the output signal of the torque balance control 10 to the speed reference L11a and inputs the value to the subtractor 31b as the speed reference L11b.

  With the configuration described above, the rotation of the rear propeller 2 is controlled based on the speed reference L11b in the same manner as the control of the front propeller 1.

  According to this embodiment, at the time of forward rotation of the contra-rotating propeller, for example, when the load is suddenly reduced such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Furthermore, each motor basically has the same torque, and motors having the same rated torque can be used.

(Second Embodiment)
With reference to FIG. 2, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  In the marine electric propulsion apparatus shown in FIG. 1, the present apparatus includes a speed reference calculator 40 b instead of the speed reference calculator 40 a, a subtracter 34 a instead of the subtractor 34 b, and a speed calculator instead of the adder 33 b. 1 except that an adder 33a is provided between the reference arithmetic unit 40b and the subtractor 31a, and the input side of the adder 33a is connected to the output side of the torque balance controller 10 via the limiter 17. Is the same.

  This device is a device that controls the counter rotation of the counter rotating propeller.

  The speed reference calculator 40b calculates a speed reference L11b serving as a reference for controlling the rotation speed of the electric motor 3b. The speed reference calculator 40b inputs the calculated speed reference L11b to the subtractor 31b.

  The subtractor 34a receives the torque reference L13a calculated by the speed controller 7a and the torque reference L13b calculated by the speed controller 7b. The subtractor 34b calculates a difference obtained by subtracting the torque reference L13a from the torque reference L13b. The subtractor 34 b inputs the calculated difference to the torque balance controller 10.

  The adder 33a receives the speed reference L11b from the speed reference calculator 40b. The adder 33a adds a value based on the output signal of the torque balance control 10 to the speed reference L11b and inputs the value to the subtractor 31b as the speed reference L11a.

  According to the present embodiment, when the counter-rotating propeller is reversely rotated, for example, when the load is suddenly reduced, such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Furthermore, each motor basically has the same torque, and motors having the same rated torque can be used.

(Third embodiment)
With reference to FIG. 3, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  In this marine electric propulsion apparatus shown in FIG. 1, this apparatus is provided with output computing units 18a and 18b, an output balance controller 19 instead of the torque balance controller 10, and a subtractor 35b instead of the subtractor 34b. Provided respectively to the input side of the subtractor 35b is connected to the output side of the output computing units 18a and 18b, and to the input side of the output computing unit 18a is connected to the output side of the speed controller 7a and the speed detector 5a 1 except that the speed controller 7b and the output side of the speed detector 5b are connected to the input side of the computing unit 18b.

  This device is a device that performs control during normal rotation of the contra-rotating propeller.

  The output calculator 18a receives a torque reference L13a calculated by the speed controller 7a and a speed feedback L12a based on the rotational speed of the motor 3a detected by the speed detector 5a. The output calculator 18a calculates the output L20a of the electric motor 3a based on the torque reference L13a and the speed feedback L12a. The output computing unit 18a inputs the computed output L20a to the subtracter 33b.

  The output calculator 18b receives a torque reference L13b calculated by the speed controller 7b and a speed feedback L12b based on the rotational speed of the motor 3b detected by the speed detector 5b. The output calculator 18b calculates the output L20b of the electric motor 3b based on the torque reference L13b and the speed feedback L12b. The output calculator 18b inputs the calculated output L20b to the subtracter 33b.

  The subtractor 35b receives the output L20a calculated by the output calculator 18a and the output L20b calculated by the output calculator 18b. The subtractor 35b calculates a difference obtained by subtracting the output L20b from the output L20a. The subtractor 35 b inputs the calculated difference to the output balance controller 19.

  The output balance controller 19 inputs an output signal to the adder 33b via the limiter 17 based on the difference input from the subtractor 35b.

  The adder 33a adds a value based on the output signal of the torque balance control 19 to the speed reference L11a and inputs the value to the subtractor 31b as the speed reference L11b.

  According to this embodiment, at the time of forward rotation of the contra-rotating propeller, for example, when the load is suddenly reduced such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Further, each motor basically has the same output, and the output can be shared equally.

(Fourth embodiment)
With reference to FIG. 4, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  In the marine electric propulsion apparatus shown in FIG. 3, the present apparatus includes a speed reference calculator 40 b instead of the speed reference calculator 40 a, a subtracter 35 a instead of the subtractor 35 b, and a speed calculator instead of the adder 33 b. 1 except that an adder 33a is provided between the reference arithmetic unit 40b and the subtractor 31a, and the input side of the adder 33a is connected to the output side of the output balance controller 19 via the limiter 17. Is the same.

  This device is a device that controls the counter rotation of the counter rotating propeller.

  The subtractor 35a receives the output L20a calculated by the output calculator 18a and the output L20b calculated by the output calculator 18b. The subtractor 35a calculates a difference obtained by subtracting the output L20a from the output L20b. The subtractor 35 a inputs the calculated difference to the output balance controller 19.

  According to the present embodiment, when the counter-rotating propeller is reversely rotated, for example, when the load is suddenly reduced, such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Further, each motor basically has the same output, and the output can be shared equally.

(Fifth embodiment)
With reference to FIG. 5, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  In the marine electric propulsion apparatus shown in FIG. 3, this apparatus is provided with voltage detectors 21a and 21b on the output side of the power converters 4a and 4b, respectively, and instead of the output calculators 18a and 18b, output calculators 18c and 18d are provided. Are connected to the input side of the subtractor 35b, the output side of the output computing units 18c and 18d is connected to the input side of the output computing unit 18c, and the output side of the voltage detector 21a and the current detector 6a is connected. 3 except that the output side of the voltage detector 21b and the current detector 6b is connected to the input side of the output computing unit 18d.

  This device is a device that performs control during normal rotation of the contra-rotating propeller.

  The voltage detector 21a detects the alternating voltage output from the power converter 4a. The voltage detector 21a inputs the detected AC voltage to the output calculator 18c.

  The voltage detector 21b detects the alternating voltage output from the power converter 4b. The voltage detector 21b inputs the detected AC voltage to the output calculator 18d.

  The current detectors 6a and 6b input the detected alternating current (current feedback L15a and L15b) to the output calculators 18c and 18d, respectively.

  The output calculator 18c calculates the output L20a of the electric motor 3a based on the AC current and the AC voltage detected from the current detector 6a and the voltage detector 21a, respectively. The output calculator 18c inputs the calculated output L20a to the subtracter 33b.

  The output calculator 18d calculates the output L20b of the electric motor 3b based on the AC current and the AC voltage detected from the current detector 6b and the voltage detector 21b, respectively. The output calculator 18d inputs the calculated output L20b to the subtracter 33b.

  The subtractor 35b receives the output L20a calculated by the output calculator 18c and the output L20b calculated by the output calculator 18d. The subtractor 35b calculates a difference obtained by subtracting the output L20b from the output L20a. The subtractor 35 b inputs the calculated difference to the output balance controller 19.

  According to this embodiment, at the time of forward rotation of the contra-rotating propeller, for example, when the load is suddenly reduced such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Further, each motor basically has the same output, and the output can be shared equally.

(Sixth embodiment)
With reference to FIG. 6, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  In the marine electric propulsion apparatus shown in FIG. 5, the present apparatus includes a speed reference calculator 40 b instead of the speed reference calculator 40 a, a subtracter 35 a instead of the subtractor 35 b, and a speed calculator instead of the adder 33 b. 5 except that an adder 33a is provided between the reference arithmetic unit 40b and the subtractor 31a, and the input side of the adder 33a is connected to the output side of the output balance controller 19 via the limiter 17. Is the same.

  This device is a device that controls the counter rotation of the counter rotating propeller.

  The subtractor 35a receives the output L20a calculated by the output calculator 18c and the output L20b calculated by the output calculator 18d. The subtractor 35a calculates a difference obtained by subtracting the output L20a from the output L20b. The subtractor 35 b inputs the calculated difference to the output balance controller 19.

  According to the present embodiment, when the counter-rotating propeller is reversely rotated, for example, when the load is suddenly reduced, such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Further, each motor basically has the same output, and the output can be shared equally.

(Seventh embodiment)
With reference to FIG. 7, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  This apparatus is provided with speed estimators 27a and 27b instead of the speed detectors 5a and 5b in the marine electric propulsion apparatus shown in FIG. 1, and the current detector 6a and the current control are provided on the input side of the speed estimator 27a. The output side of the speed estimator 27b is connected to the output side of the current detector 6b and the current controller 9b, and the output side of the speed estimators 27a and 27b is connected to the subtractors 31a and 31b. 1 is the same as FIG.

  This device is a device that performs control during normal rotation of the contra-rotating propeller.

  The speed estimator 27a calculates an estimated speed L28a obtained by estimating the rotational speed of the electric motor 3a based on the alternating current detected by the current detector 6a and the voltage reference L16a calculated by the current controller 9a. The speed estimator 27a inputs the calculated estimated speed L28a to the subtractor 31a. The estimated speed L28a is used as a speed feedback signal of the electric motor 3a.

  The speed estimator 27b calculates an estimated speed L28b obtained by estimating the rotational speed of the electric motor 3b based on the alternating current detected by the current detector 6b and the voltage reference L16b calculated by the current controller 9b. The speed estimator 27b inputs the calculated estimated speed L28b to the subtractor 31b. The estimated speed L28b is used as a speed feedback signal of the electric motor 3b.

  According to this embodiment, at the time of forward rotation of the contra-rotating propeller, for example, when the load is suddenly reduced such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Furthermore, each motor basically has the same torque, and motors having the same rated torque can be used. Further, the present invention can also be applied to ships and the like when the speed detector cannot be wired because the installation space is small or when it is difficult to route the signal line of the speed detector.

(Eighth embodiment)
With reference to FIG. 8, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  In the marine electric propulsion apparatus shown in FIG. 7, the present apparatus includes a speed reference calculator 40 b instead of the speed reference calculator 40 a, a subtracter 34 a instead of the subtractor 34 b, and a speed calculator instead of the adder 33 b. Except for the point that an adder 33a is provided between the reference arithmetic unit 40b and the subtractor 31a, and the input side of the adder 33a is connected to the output side of the torque balance controller 10 via the limiter 17. Is the same.

  This device is a device that controls the counter rotation of the counter rotating propeller.

  According to the present embodiment, when the counter-rotating propeller is reversely rotated, for example, when the load is suddenly reduced, such as when the propeller goes out to sea, it is possible to prevent the motor speed from rapidly increasing. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Furthermore, each motor basically has the same torque, and motors having the same rated torque can be used. Further, the present invention can also be applied to ships and the like when the speed detector cannot be wired because the installation space is small or when it is difficult to route the signal line of the speed detector.

(Ninth embodiment)
With reference to FIG. 9, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  This apparatus is the marine electric propulsion apparatus shown in FIG. 1 except that the speed reference calculator 40a is provided instead of the speed reference calculator 40a, the adder 33b is removed, the switching controller 25, the switches 24a and 24b, the subtractor 36a, An adder 36b is provided.

  The switch 24a is provided between the speed reference calculator 40 and the subtractor 31a. The switch 24b is provided between the speed reference calculator 40 and the subtractor 31b. The subtractor 36a is provided between the speed reference computing unit 40 and the b contact (break contact) of the switch 24a. The adder 36b is provided between the speed reference calculator 40 and the a contact (make contact) of the switch 24b. The output side of the limiter 17 is connected to the input side of the subtracter 36a and the adder 36b.

  Except for these points, it is the same as FIG.

  The switching controller 25 switches the switch 24a and the switch 24b in conjunction with each other. The switching controller 25 is a device for switching between control during forward rotation and reverse rotation of the contra-rotating propeller.

  First, control during normal rotation of the contra-rotating propeller will be described.

  In the state where the forward rotation is controlled, in this apparatus, both the switches 24a and 24b make the a contact. When the state is in the state of controlling the reverse rotation time, the switching controller 25 can switch to the state of controlling the forward rotation time.

  The speed reference calculator 40 calculates a speed reference L11a that is a reference for controlling the rotation speed of the electric motor 3a. The speed reference calculator 40 inputs the calculated speed reference L11a to the subtractor 31a via the switch 24a. The speed reference calculator 40 inputs the calculated speed reference L11a to the adder 36b.

  The adder 36b receives the speed reference L11a input from the speed reference calculator 40 and the output signal of the torque balance controller 10 input via the limiter 17. The adder 36b adds a value based on the output signal of the torque balance control 10 to the speed reference L11a and inputs the value to the subtractor 31b as the speed reference L11b.

  Next, control during reverse rotation of the counter rotating propeller will be described.

  In the state of controlling the reverse rotation time, the switch 24a and 24b both make the b contact. If the state is in the state of controlling the forward rotation time, the switching controller 25 can switch to the state of controlling the reverse rotation time.

  The speed reference calculator 40 calculates a speed reference L11b that serves as a reference for controlling the rotation speed of the electric motor 3b. The speed reference calculator 40 inputs the calculated speed reference L11b to the subtractor 31b via the switch 24b. The speed reference calculator 40 inputs the calculated speed reference L11b to the subtractor 36a.

  The subtractor 36 a receives the output of the torque balance controller 10 input via the speed reference L11 b input from the speed reference calculator 40 and the limiter 17. The subtractor 36a subtracts a value based on the output signal of the torque balance control 10 from the speed reference L11b and inputs the value to the subtractor 31b as the speed reference L11a.

  According to the present embodiment, at both the forward rotation and the reverse rotation of the contra-rotating propeller, for example, when the load is suddenly reduced such as when the propeller goes out to the sea, the motor speed is prevented from rapidly increasing. be able to. In addition, the device configuration can be simplified as compared with the propulsion method using a diesel engine. Furthermore, each motor basically has the same torque, and motors having the same rated torque can be used.

(Tenth embodiment)
With reference to FIG. 10, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  This apparatus removes the subtractor 34b, the torque balance control 10, the limiter 17, and the adder 33b in the marine electric propulsion apparatus shown in FIG. 1, and instead, functions between the speed reference calculator 40a and the subtractor 31b. It is the same as FIG. 1 except that the calculator 22a is provided.

  As shown in FIG. 13, the function calculator 22a determines a speed reference L11b (rotation speed of the electric motor 3b) from the speed reference L11a (rotation speed of the electric motor 3a) in order to efficiently operate the counter rotating propeller. A function 23a is set for this purpose. Accordingly, when the speed reference L11a is determined, the speed reference L11b is determined.

  The function calculator 22a calculates the speed reference L11b based on the speed reference L11a input from the speed reference calculator 40a. The function calculator 22a inputs the calculated speed reference L11b to the subtractor 31b.

  According to this embodiment, at the time of forward rotation of the contra-rotating propeller, the device configuration can be simplified as compared with the propulsion method using the diesel engine. Further, the front propeller 1 and the rear propeller 2 can be operated at an efficient speed in which the two electric motors 3a and 3b are balanced in the entire speed range.

(Eleventh embodiment)
With reference to FIG. 11, the structure of the marine electric propulsion apparatus which concerns on this embodiment is demonstrated.

  In the marine electric propulsion apparatus shown in FIG. 10, this apparatus is provided with a speed reference calculator 40b instead of the speed reference calculator 40a, and instead of the function calculator 22a, a speed reference calculator 40b and a subtractor 31a. It is the same as FIG. 10 except that a function calculator 22b is provided between them.

  As shown in FIG. 14, the function calculator 22b determines a speed reference L11a (rotation speed of the electric motor 3a) from the speed reference L11b (rotation speed of the electric motor 3b) in order to efficiently operate the counter rotating propeller. A function 23b is set. Accordingly, when the speed reference L11b is determined, the speed reference L11a is determined.

  The function calculator 22b calculates the speed reference L11a based on the speed reference L11b input from the speed reference calculator 40b. The function calculator 22b inputs the calculated speed reference L11a to the subtractor 31a.

  According to the present embodiment, when the counter-rotating propeller is reversed, the device configuration can be simplified as compared with the propulsion method using a diesel engine or the like. Further, the front propeller 1 and the rear propeller 2 can be operated at an efficient speed in which the two electric motors 3a and 3b are balanced in the entire speed range.

  In each embodiment, an arbitrary part constituting the apparatus may use either software or hardware. You may select a structure according to the conditions concerning manufacture, the environment applied, etc.

  In each embodiment, an arbitrary part (for example, a subtractor, an adder, etc.) constituting the apparatus is the same as the gist of each embodiment (for example, the output and torque of two motors, the output of two power converters, etc. If it does not deviate from the above, the configuration may be changed according to the manufacturing conditions and the applied environment.

  For example, in the subtractor in each embodiment, any input may be used as the addition side or the subtraction side as long as a process for obtaining a difference between two inputs is performed.

  In the first to eighth embodiments, the subtractors 34a and 34b and the subtractors 35a and 35b that are input to the torque balance controller 10 and the output balance controller 19 are interchanged with each other (addition side and subtraction). The adders 33a and 33b may be changed to subtracters by switching the input to the side, ie, inverting the sign of the difference.

  Similarly, in the ninth embodiment, the subtractor 34b may be replaced with the subtractor 34a, and the subtractor 36a and the adder 36b may be replaced with each other.

  The speed estimators 27a and 27b in the seventh embodiment and the eighth embodiment may be used instead of the speed detectors 5a and 5b in the other embodiments. As a result, in addition to the effects in the other embodiments, the present invention can be applied to ships and the like when the speed detector cannot be wired because the mounting space is small or when the signal line of the speed detector is difficult to route. Effects such as can be obtained.

  The speed estimators 27a and 27b in the seventh and eighth embodiments are based on the alternating current output from the power converters 4a and 4b and the voltage references L16a and L16b used for controlling the power converters 4a and 4b. Although the rotation speeds of the electric motors 3a and 3b are estimated, the rotation speeds of the electric motors 3a and 3b may be estimated by other methods, methods, and apparatuses. For example, the speed estimation method may be performed directly or indirectly from the motor terminal voltage, current, and motor constant. Moreover, you may estimate the rotational speed of the electric motors 3a and 3b based on the voltage feedback and electric current feedback which measured between the terminals of the motor with the voltage sensor (for example, refer nonpatent literature 1).

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

The block diagram for demonstrating the ship electric propulsion apparatus which concerns on the 1st Embodiment of this invention. The block diagram for demonstrating the marine electric propulsion apparatus which concerns on 2nd Embodiment. The block diagram for demonstrating the marine electric propulsion apparatus which concerns on 3rd Embodiment. The block diagram for demonstrating the ship electric propulsion apparatus which concerns on 4th Embodiment. The block diagram for demonstrating the ship electric propulsion apparatus which concerns on 5th Embodiment. The block diagram for demonstrating the marine electric propulsion apparatus which concerns on 6th Embodiment. The block diagram for demonstrating the ship electric propulsion apparatus which concerns on 7th Embodiment. The block diagram for demonstrating the ship electric propulsion apparatus which concerns on 8th Embodiment. The block diagram for demonstrating the ship electric propulsion apparatus which concerns on 9th Embodiment. A block diagram for explaining a marine electric propulsion device concerning a 10th embodiment. A block diagram for explaining a marine electric propulsion device concerning an 11th embodiment. The block diagram for demonstrating the contra-rotating propeller which concerns on each embodiment. The block diagram for demonstrating the function of the function calculator which concerns on 10th Embodiment. The block diagram for demonstrating the function of the function calculator which concerns on 11th Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Front propeller, 2 ... Rear propeller, 3a, 3b ... Electric motor, 4a, 4b ... Power converter, 5a, 5b ... Speed detector, 6a, 6b ... Current detector, 7a, 7b ... Speed controller, 8a, 8b ... current reference arithmetic unit, 9a, 9b ... current controller, 10 ... torque balance controller, 17 ... limiter, 31a, 31b, 32a, 32b, 34a, 34b ... subtractor, 33a, 33b ... adder, 40a, 40b: Speed reference calculator.

Claims (6)

A counter rotating propeller in which two propellers rotate in opposite directions, two electric motors that rotate each propeller, and a speed reference that is a reference for controlling the rotation speed of each electric motor are input, In a marine electric propulsion apparatus that has two torque reference calculation means for calculating torque reference for controlling the torque of each electric motor, and controls each of the electric motors based on the speed reference,
Based on each torque reference calculated by each torque reference calculation means, the speed reference input to any one of the torque reference calculation means is corrected so that the torque of each motor becomes equal. A marine electric propulsion device characterized by comprising torque balance control means. A counter rotating propeller in which two propellers rotate in opposite directions, two electric motors that rotate each propeller, and a speed reference that is a reference for controlling the rotation speed of each electric motor are input, In a marine electric propulsion apparatus that has two torque reference calculation means for calculating torque reference for controlling the torque of each electric motor, and controls each of the electric motors based on the speed reference,
Two speed detecting means for detecting the rotational speed of each electric motor;
Two output calculation means for calculating the output of each motor based on the torque reference calculated by the torque reference calculation means and the rotational speed detected by the speed detection means, corresponding to each motor. ,
An output for correcting the speed reference input to any one of the torque reference calculation means so that the outputs of the motors are equal based on the outputs calculated by the output calculation means. A marine electric propulsion device comprising balance control means. A counter rotating propeller in which two propellers rotate in opposite directions, two electric motors that rotate each propeller, and a speed reference that is a reference for controlling the rotation speed of each electric motor are input, In a marine electric propulsion apparatus that has two torque reference calculation means for calculating torque reference for controlling the torque of each electric motor, and controls each of the electric motors based on the speed reference,
Two speed estimating means for estimating the rotational speed of each electric motor;
Two speed reference correcting means for correcting each of the speed references corresponding to the respective speed estimating means based on the respective rotational speeds estimated by the respective speed estimating means;
Based on each speed reference corrected by each speed reference correction means, the speed reference input to any one of the torque reference calculation means is corrected so that the torque of each motor becomes equal. A marine electric propulsion device characterized by comprising torque balance control means. A counter rotating propeller in which two propellers rotate in opposite directions, two electric motors that rotate each propeller, and a speed reference that is a reference for controlling the rotation speed of each electric motor are input, Two torque reference calculating means for calculating torque reference for controlling the torque of each motor, and two power converters for supplying AC power to each motor, and based on the speed reference, In the marine electric propulsion device that controls the output of each electric motor via each power converter,
Two current detection means for detecting the current output from each of the power converters;
Two voltage detection means for detecting the voltage output from each of the power converters;
Based on the current detected by the current detection means and the voltage detected by the voltage detection means for the power converter corresponding to each electric motor and supplying AC power to the motor, the electric motors Two output calculation means for calculating the outputs of
An output for correcting the speed reference input to any one of the torque reference calculation means so that the outputs of the motors are equal based on the outputs calculated by the output calculation means. A marine electric propulsion device comprising balance control means. Based on a speed reference that is a reference for controlling the rotational speed of each electric motor, including a counter rotating propeller in which two propellers rotate in opposite directions and two electric motors that rotate each of the propellers. In the marine electric propulsion device that controls each of the electric motors,
A marine electric propulsion device comprising speed reference calculation means for calculating the other speed reference according to a predetermined function based on the speed reference for controlling any one of the motors. Control switching means for switching the control between the forward rotation and the reverse rotation when the predetermined rotation direction of each propeller is forward rotation, the reverse rotation direction to the forward rotation direction is reverse rotation, and The marine electric propulsion device according to any one of claims 1 to 5, further comprising:

Images