JP2019217817A - Power control device for vessel - Google Patents

Abstract

To reduce quantity of a regenerative resistor consuming regenerative electric power by converting to heat by efficiently using regenerative power generated when a dynamo-electric motor is decelerated in a vessel provided with the dynamo-electric motor for propulsion.SOLUTION: A power conversion device for converting power supplied from an inboard power distribution system to power for driving a dynamo-electric motor is provided with a rectifier capable of power source regeneration and a regenerative resistor. The power control device for vessel, when regenerative power is generated in the dynamo-electric motor, starts resistance regeneration by having regenerated electric power consumed by the regenerative resistor, and starts power source regeneration for restoring the regenerative electric power from the rectifier to the inboard power distribution system after start of resistance regeneration. Then, after starting of power source regeneration, transition processing is carried out for gradually transiting a load destination of the regenerative electric power from the regenerative resistor to the inboard power distribution system.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a marine power control device, and more particularly, to a propulsion motor, an onboard distribution system including a generator, and a power conversion device for converting power supplied from the onboard distribution system into power for driving the motor. And a regenerative resistor capable of regenerating power and a regenerative resistor, which are suitable for use in a ship provided in a power converter.

  2. Description of the Related Art Conventionally, in a boat propelled by an electric motor, it is general that regenerative electric power generated by the electric motor during deceleration is returned to heat by a regenerative resistor and consumed. In recent years, regenerative power has also been returned to an onboard distribution system by a power converter including a rectifier capable of power regeneration.

  Furthermore, as disclosed in Patent Literature 1, it has been proposed to use both a method in which regenerative power is consumed by a regenerative resistor and a method in which regenerative power is returned to an onboard distribution system by power regeneration. According to the method disclosed in Patent Document 1, the motor is decelerated and the converter (rectifier capable of power regeneration) is switched to regeneration mode operation, and at the same time, the braking resistance (regenerative resistor) is switched on. ) Is connected. As a result, a part of the regenerative electric power generated by the deceleration of the motor is regenerated (returned) to the power supply (onboard distribution system) via the converter, and the rest is consumed as braking electric power by the braking resistor.

  Patent Literature 1 discloses an advantage of using the two methods in combination, as follows: "Since the capacity of the braking resistor can be reduced by the regenerative capacity to the power supply, the effect of making the braking resistor smaller can be obtained. It is described. However, even if there is a certain amount of regenerative capacity on the side of the onboard power supply unit, simply connecting the braking resistor at the same time as switching the mode of the converter does not increase the power regenerated by the power source. The power consumed is not small. In other words, the technique disclosed in Patent Document 1 cannot be said to be insufficient for the purpose of reducing the braking resistance, that is, reducing the amount of the regenerative resistor.

  Patent Document 2 proposes that a regenerative electric power generated by an electric motor be absorbed by a power storage device to omit a back power absorber (regenerative resistor). However, no consideration is given to the temporal change in regenerative power, and no mention is made of the existence of a response delay in the power control device and the power storage device. Simply replacing the back power absorber with a power storage device cannot optimize the entire system. For this reason, in the technique disclosed in Patent Literature 1, the regenerative electric power generated by the motor cannot be sufficiently absorbed, and the motor may not be able to be decelerated.

JP 2007-125909 A JP 2013-35297 A

  The present invention has been made in view of the above-described problems, and in a ship equipped with a propulsion motor, the regenerative power is converted into heat by effectively utilizing regenerative power generated when the motor is decelerated. An object is to reduce the amount of a regenerative resistor to be consumed.

  A marine power control device according to the present invention converts a propulsion motor, a generator, an onboard distribution system connected to the generator, and power supplied from the onboard distribution system into power for driving the motor. A marine vessel equipped with a power conversion device, wherein a rectifier capable of power regeneration and a regenerative resistor are used in a power control device used in a marine vessel provided with the power conversion device, wherein the following processing is performed. I do.

  That is, the marine power control device according to the present invention, when regenerative power is generated by the motor, starts resistance regeneration to consume the regenerative power to the regenerative resistor, and after the start of the resistance regeneration, from the rectifier to the onboard distribution system. The power regeneration for returning the regenerative electric power is started, and after the start of the regenerative electric power, a transition process is performed in which the regenerative electric power is gradually transferred from the regenerative resistor to the onboard distribution system.

  In the transition process, the power of the difference between the regenerative power and the power that can be returned to the onboard distribution system by the power regeneration may be consumed by the regenerative resistor by the resistance regeneration.

  Further, when regenerative electric power is generated by the motor, a generator output reduction process for temporarily reducing the output of the generator may be performed.

  When regenerative electric power is generated by the electric motor, a motor output reduction process for temporarily reducing the output of the motor that drives the generator may be performed.

  Further, the onboard distribution system may be connected to a power storage device.

  The regenerative power generated by the motor during deceleration increases and decreases with time. Then, while the regenerative power in the initial stage of the regenerative operation rises sharply, there is a time delay before the power regeneration becomes possible due to the response delay of the rectifier. According to the marine power control device of the present invention, when regenerative power is generated by the electric motor, first, the response is performed by a responsive operation by the regenerative resistor, and after the power regeneration is started by the response of the subsequent rectifier, The burden of regenerative power will gradually shift from the regenerative resistor to the onboard distribution system. By performing such processing, the regenerative electric power can be effectively used in the onboard distribution system, and the amount of the regenerative resistor can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the electric propulsion system for ships which concerns on Embodiment 1 of this invention. FIG. 4 is a diagram illustrating a control example of regenerative power distribution control according to Embodiment 1 of the present invention. It is a figure which shows the structure of the electric propulsion system for ships which concerns on Embodiment 2 of this invention. It is a figure which shows the structure of the electric propulsion system for ships which concerns on Embodiment 3 of this invention. FIG. 13 is a diagram illustrating a control example of regenerative power distribution control according to Embodiment 3 of the present invention. It is a figure which shows the structure of the electric propulsion system for ships which concerns on Embodiment 4 of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, in the embodiments described below, when referring to the number of each element, such as the number, quantity, amount, range, etc., unless otherwise specified or in principle clearly specified by the number, the reference The present invention is not limited to the number described above. The structures described in the following embodiments are not necessarily essential to the present invention, unless otherwise specified or clearly specified in principle.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of the electric propulsion system for a marine vessel according to Embodiment 1 of the present invention. In the marine electric propulsion system of the present embodiment, the electric power generated by the generator 1 is supplied to the propulsion power conversion device 3 and the onboard load 16 via the onboard distribution system 2. The onboard load 16 includes, for example, equipment that consumes power for purposes other than propulsion, such as navigation equipment, electric pumps, lighting equipment and air conditioning equipment used onboard.

  The propulsion power conversion device 3 is a device that converts power supplied from the onboard distribution system 2 into power for driving the propulsion motor 4. The propulsion power converter 3 includes a rectifier 5 for rectifying AC power, a DC link 8 including a smoothing capacitor, and an inverter (inverter) 9. The inverter 9 converts the smoothed DC voltage into a variable voltage / variable frequency AC voltage, and outputs an AC voltage to the propulsion motor 4. The propulsion motor 4 is connected to a propulsion propeller (not shown) via a propeller shaft (not shown) or a reduction gear (not shown). In a normal propulsion state of the ship, the rectifier 5 supplies power to the inverter 9 via the DC link 8, and the output of the inverter 9 drives the propulsion motor 4.

  The rectifier 5 is a regenerable converter. The rectifier 5 may have the same circuit configuration as the inverter 9 or may have a different circuit configuration. When regenerative electric power is generated by the propulsion motor 4 during deceleration, the regenerative electric power can be returned from the rectifier 5 to the side of the onboard distribution system 2. In addition, the propulsion power conversion device 3 includes a regenerative resistor 7 and a regenerative resistor switch 6 for controlling the energized state of the regenerative resistor 7. As the regenerative resistor switch 6, for example, an IGBT can be used. In a normal propulsion state of the ship, the regenerative resistor switch 6 is kept off, and the regenerative resistor 7 is kept in a non-energized state. When regenerative electric power is generated by the propulsion motor 4, the regenerative electric power can be converted into heat by the regenerative electric resistor 7 and consumed by turning on the regenerative electric resistor switch 6 to turn on the regenerative electric resistor 7. . Hereinafter, the act of returning regenerative power from the rectifier 5 to the onboard distribution system 2 is referred to as power regeneration, and the act of causing the regenerative resistor 7 to consume regenerative power is referred to as resistance regeneration.

  The propulsion power converter 3 includes a propulsion power converter control device 10. The operations of the rectifier 5, the regenerative resistor switch 6, and the inverter 9 are performed by the rectifier control signal 11, the regenerative resistor switch control signal 12, and the inverter control signal 14 issued from the propulsion power converter controller 10. Are controlled respectively. A voltage applied to the DC link 8 is detected by a voltmeter (not shown), and a DC link voltage detection signal 13 indicating the voltage value is input to the propulsion power converter control device 10. Further, a current flowing through the propulsion motor 4 or a current flowing from the propulsion motor 4 is detected by an ammeter (not shown), and a motor current detection signal 15 indicating the current value is input to the propulsion power converter control device 10. At the time of deceleration, the propulsion power converter control device 10 calculates the power regeneration amount obtained by the propulsion motor 4 based on the DC link voltage detection signal 13 and the motor current detection signal 15.

  The marine power control device 17 constantly monitors the power regeneration amount 20 of the propulsion motor 4 transmitted from the propulsion power conversion device control device 10. When the vessel starts to decelerate and regenerative power is generated, the marine power control device 17 performs regenerative power distribution control for distributing the regenerative power to the onboard distribution system 2 and the regenerative resistor 7.

  In the regenerative power distribution control by the marine power control device 17, first, based on the power regeneration amount 20, regenerative power borne by power regeneration and regenerative power borne by resistance regeneration are calculated. Then, the regenerative power amount command 18 is issued to the propulsion power converter control device 10 based on the regenerative power borne by the power regeneration, and the power consumption command 19 is generated based on the regenerative power borne by the resistance regeneration. To emit. The propulsion power converter control device 10 adjusts the rectifier control signal 11 based on the regenerative electric energy command 18 so that the electric power is allocated according to the command value, and changes the regenerative resistor switch control signal 12 to the power consumption. The adjustment is performed based on the command 19.

  FIG. 2 is a diagram illustrating a control example of regenerative power distribution control according to the present embodiment. The upper graph in FIG. 2 shows a temporal transition of the total regenerative power generated by the propulsion motor 4, the power burden on the regenerative resistor 7, and the power returned to the onboard distribution system 2. In addition, the lower graph of FIG. 2 shows a temporal transition of the power consumption of the onboard load 16 and the output power of the generator 1. In the regenerative power distribution control according to the present embodiment, the power load is inclinedly distributed to the regenerative resistor 7 in the initial stage of regeneration in consideration of the delay in the output control of the generator 1, and thereafter, the power load is transferred to the onboard distribution system 2. Is done.

  A control example of the regenerative power distribution control shown in FIG. 2 will be specifically described. In this example, time 0 is set as the generation start time of the regenerative power. When the regenerative power is generated, the marine power control device 17 that constantly monitors the power regeneration amount 20 transmitted from the propulsion power conversion device control device 10 uses the regenerative resistor for the regenerative resistor via the propulsion power conversion device control device 10. A switch control signal for a regenerative resistor is issued to the switch. The regenerative resistor switch 6 is turned on by the regenerative resistor switch control signal 12, and the regenerative resistor 7 is turned on. Then, when the regenerative resistor 7 is turned on, the regenerative power starts to be consumed by the regenerative resistor 7. In addition, surplus occurs in the power supply, and the voltage of the onboard distribution system 2 starts to increase.

  At a time t1, which is slightly delayed from the generation start time of the regenerative electric power, the output of the generator 1 starts to decrease due to an increase in the voltage of the onboard distribution system 2. The decrease in the output of the generator 1 is achieved by an automatic voltage adjustment function by a generator voltage control device (AVR) and a motor output control device (governor) described later.

  At time t2, which is slightly later than the decrease in the output of the generator 1, the marine power control device 17 issues a rectification device control signal 11 to the rectification device 5 via the propulsion power conversion device control device 10, and the rectification device 5 To start power regeneration. With the start of power regeneration, the power returned to the onboard distribution system 2 begins to increase. Note that there is a response delay from the generation of regenerative electric power to the completion of preparation for power regeneration in the propulsion electric power converter 3. The time from time 0 to time t2 corresponds to a response delay time in the propulsion power converter 3.

  After the start time t2 of the power regeneration, the marine power control device 17 adjusts the rectifier control signal 11 and the regenerative resistor switch control signal 12 respectively to reduce the power burden from the regenerative resistor 7 to the onboard distribution system 2. A transition process that gradually transitions to is performed. As a specific example, the rectifier control signal 11 is a PWM signal applied to the power semiconductor element included in the rectifier 5, and the regenerative resistor switch control signal 12 is a PWM signal applied to the power semiconductor element included in the regenerative resistor switch 6. Signal. The marine vessel power control device 17 increases the duty ratio of the regenerative resistor switch control signal 12 once to a maximum, and then gradually reduces the duty ratio to a minimum. To increase. As a result, it is possible to increase the return power to the onboard distribution system 2 while reducing the power burden on the regenerative resistor 7.

  Adjustment of the rectifier control signal 11 and the regenerative resistor switch control signal 12 is performed, for example, according to map data stored in the memory of the marine power control device 17. The process of shifting the power burden is continued until the power burden on the regenerative resistor 7 becomes zero. In this example, the time t3 is set as the completion time of the transfer of the power burden destination. At time t3, the duty ratio of the regenerative resistor switch control signal 12 is minimized, and the duty ratio of the rectifier control signal 11 is maximized.

  During the transition process, the power of the difference between the regenerative power and the power that can be returned to the onboard distribution system 2 by the power regeneration is consumed by the regenerative resistor 7 by the resistance regeneration. On the other hand, all the regenerated electric power is returned to the onboard distribution system 2 after the transfer completion time t3 of the power receiving party. Return of the regenerative power to the onboard distribution system 2 is continued until time t4 when the generation of the regenerative power ends. When the generation of the regenerative electric power is completed, the marine power control device 17 stops the emission of the rectification device control signal 11 from the propulsion power conversion device control device 10 to the rectification device 5.

  As shown in the upper graph of FIG. 2, the total regenerative power generated by the propulsion motor 4 during deceleration increases and decreases with time. Then, while the regenerative power in the initial stage of the regenerative operation rises sharply, there is a time delay before the power regeneration becomes possible due to the response delay of the rectifier 5. According to the above-described regenerative power distribution control, when regenerative power is generated in the propulsion motor 4, the regenerative resistor 7 first responds to the regenerative power, and after that, power regeneration is started by the response of the rectifier 5. Gradually transfers the regenerative electric power from the regenerative resistor 7 to the onboard distribution system 2. By performing such processing, the regenerative electric power can be effectively used in the onboard distribution system 2 and the amount of the regenerative resistor 7 can be reduced.

  In the regenerative power distribution control, both the duty ratio of the regenerative resistor switch control signal 12 and the duty ratio of the rectifier control signal 11 are gradually changed, but only the duty ratio of one of the signals is gradually changed. It may be done. For example, the duty ratio of the rectifier control signal 11 may be gradually increased from the minimum to the maximum from time t2 while the duty ratio of the regenerative resistor switch control signal 12 is maintained at the maximum. In this case, the power burden on the regenerative resistor 7 gradually decreases as the duty ratio of the rectifier control signal 11 increases and the return power to the onboard distribution system 2 increases.

Embodiment 2 FIG.
FIG. 3 is a diagram showing a configuration of an electric propulsion system for a marine vessel according to Embodiment 2 of the present invention. In this figure, the same reference numerals are assigned to elements common to those of the first embodiment. In the following description, the configuration already described in the first embodiment will be omitted, and a configuration unique to the present embodiment will be described.

  The generator 1 is provided with a generator voltage controller (AVR) 23 for controlling the voltage. When regenerative power is generated by the propulsion motor 4, the marine power control device 17 issues a generator output reduction command 24 to the generator voltage control device 23 in addition to the operation of the first embodiment. The generator voltage control device 23 that has received the generator output reduction command 24 actively reduces the output of the generator 1 temporarily. By performing such a generator output reduction process in the regenerative power distribution control, the delay of the output control of the generator 1 is improved, and the load transfer from the regenerative resistor 7 to the onboard distribution system 2 is realized in a shorter time. be able to. That is, according to the present embodiment, it is possible to further effectively use the regenerative power and reduce the amount of the regenerative resistor 7.

Embodiment 3 FIG.
FIG. 4 is a diagram showing a configuration of a marine electric propulsion system according to Embodiment 3 of the present invention. In this figure, the same reference numerals are assigned to elements common to those of the second embodiment. In the following description, the configuration already described in the first or second embodiment will be omitted, and a configuration unique to the present embodiment will be described.

  The generator 1 is driven by a prime mover (for example, a diesel engine) 25, and the prime mover 25 is provided with a prime mover output control device (governor) 26 for controlling its output. When the regenerative electric power is generated by the propulsion motor 4, the marine power control device 17 issues a prime mover output reduction command 27 to the prime mover output control device 26 in addition to the operation of the second embodiment. The prime mover output control device 26 that has received the prime mover output reduction command 27 actively reduces the output of the prime mover 25 temporarily. By performing such a motor output reduction process in the regenerative power distribution control, the delay in the output control of the generator 1 is further improved, and the load transfer from the regenerative resistor 7 to the onboard distribution system 2 is realized in a shorter time. be able to. That is, according to the present embodiment, the regenerative electric power can be more effectively used and the amount of the regenerative resistor 7 can be further reduced as compared with the second embodiment.

  FIG. 5 is a diagram illustrating a control example of regenerative power distribution control according to the present embodiment. The upper graph in FIG. 5 shows a temporal transition of the total regenerative power generated by the propulsion motor 4, the power burden on the regenerative resistor 7, and the power returned to the onboard distribution system 2. The lower graph in FIG. 5 shows the power consumption of the onboard load 16, the output power of the generator 1, the contribution of the generator voltage control to the decrease in the output power of the generator 1, and the 2 shows a temporal change with respect to the contribution of the motor output control to the decrease in the output power of the motor.

  A control example of the regenerative power distribution control shown in FIG. 5 will be specifically described. In this example, time 0 is set as the generation start time of the regenerative power. The marine power control device 17 detects the generation of regenerative power based on the power regeneration amount 20 transmitted from the propulsion power conversion device control device 10. When the generation of regenerative power is detected, the marine power control device 17 outputs the regenerative resistor switch control signal 12 to the regenerative resistor switch 6 via the propulsion power converter control device 10, and also controls the generator voltage control. A generator output reduction command 24 is issued to the device 23, and a motor output reduction command 27 is issued to the motor output control device 26.

  At time 0, the regenerative resistor switch 6 is turned on by the regenerative resistor switch control signal 12. As a result, the regenerative resistor 7 is turned on and the power is started to be consumed by the regenerative resistor 7. Further, at time 0, the voltage control of the generator 1 by the generator output reduction command 24 and the output control of the motor 25 by the motor output reduction command 27 are started, so that the output of the generator 1 Start to fall without delay.

  At time t2 after the elapse of the response delay time from the generation of the regenerative electric power to the completion of the preparation of the propulsion power conversion device 3, the marine power control device 17 controls the rectification device via the propulsion power conversion device control device 10. A rectifier control signal 11 is issued to the rectifier 5 to instruct the rectifier 5 to start power regeneration. With the start of power regeneration, the power returned to the onboard distribution system 2 begins to increase.

  After the start time t2 of the power regeneration, the marine power control device 17 adjusts the rectifier control signal 11 and the regenerative resistor switch control signal 12 respectively to reduce the power burden from the regenerative resistor 7 to the onboard distribution system 2. It gradually shifts to. According to the regenerative power distribution control according to the present embodiment, the output control of prime mover 25 and the voltage control of generator 1 are started simultaneously with the generation of regenerative power, so that the output of generator 1 is used to generate regenerative power. The load can be reduced without delay, and the load transfer from the regenerative resistor 7 to the onboard distribution system 2 can be realized in a short time. The operation of the regenerative power distribution control according to the present embodiment after time t2 is the same as that of the first embodiment, and thus the description is omitted.

  In the above-described regenerative power distribution control, when regenerative power is generated, the generator output lowering process and the motor output lowering process are performed. However, only the motor output lowering process may be performed.

Embodiment 4 FIG.
FIG. 6 is a diagram showing a configuration of the electric propulsion system for a marine vessel according to Embodiment 4 of the present invention. In this figure, the same reference numerals are assigned to elements common to those of the first embodiment. In the following description, the configuration already described in the first embodiment will be omitted, and a configuration unique to the present embodiment will be described.

  In the marine electric propulsion system according to the present embodiment, an electric power storage device 28 is connected to the inboard distribution system 2. The power storage device 28 is preferably a power storage device corresponding to a pulsed power load. The marine power control device 17 constantly monitors the power storage amount signal 29 transmitted from the power storage device 28. When regenerative electric power is generated in the propulsion motor 4, the marine power control device 17 determines from the electric power storage amount signal 29 whether or not the electric power storage device 28 has a margin for receiving electric power. When the power storage device 28 has a margin for receiving power, the regenerative power is inclinedly distributed to the onboard distribution system 2 and a power storage command 30 is issued to the power storage device 28 to reduce the regenerative power as much as possible. The power is transferred to the power storage device 28. By performing such an operation in the regenerative power distribution control, it is possible to further effectively use the regenerative power and reduce the amount of the regenerative resistor 7. The power storage device 28 of the present embodiment can also be applied to the marine electric propulsion system according to the second or third embodiment.

REFERENCE SIGNS LIST 1 Generator 2 Onboard distribution system 3 Propulsion power converter 4 Propulsion motor 5 Regenerative rectifier 6 Regenerative resistor switch 7 Regenerative resistor 8 DC link 9 Inverter 10 Propulsion power converter controller 11 Rectifier control Signal 12 Regenerative resistor switch control signal 13 DC link voltage detection signal 14 Inverter control signal 15 Motor current detection signal 16 Onboard load 17 Vessel power control device 18 Regeneration power amount command to onboard distribution system 19 Regeneration resistor Power consumption command 20 Power regeneration amount from propulsion motor 21 Power consumption of onboard load 22 Generator output power 23 Generator voltage controller (AVR)
24 Generator output reduction command 25 Prime mover 26 Prime mover output control device (governor)
27 Power reduction command 28 Power storage device 29 Power storage signal 30 Power storage command

Claims (5)

A vessel including a propulsion motor, a generator, an onboard distribution system connected to the generator, and a power conversion device that converts power supplied from the onboard distribution system into power for driving the motor. A power control device used in a ship provided with a rectifier and a regenerative resistor capable of power regeneration and the power converter,
When regenerative power is generated in the electric motor, start regenerative regeneration that causes the regenerative power to be consumed by the regenerative resistor,
After the start of the resistance regeneration, start the power regeneration to return the regenerative power from the rectifier to the onboard distribution system,
After the start of the power regeneration, the power control device for a marine vessel performs a transition process for gradually shifting a recipient of the regenerative power from the regenerative resistor to the onboard distribution system. The said shift process WHEREIN: The electric power of the difference of the electric power which can be returned to the inboard power distribution system by the said regenerative electric power and the said power supply regeneration is made to be consumed by the said regenerative resistor by the said resistance regeneration. Power control equipment for ships. 3. The power control device for a boat according to claim 1, wherein when the regenerative power is generated, a generator output reduction process for temporarily reducing an output of the generator is performed. 4. The power control device for a marine vessel according to claim 3, wherein when the regenerative electric power is generated, a motor output reduction process for temporarily reducing the output of a motor that drives the generator is performed. The marine power control device according to any one of claims 1 to 4, wherein a power storage device is connected to the onboard distribution system.

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