System for controlling power of ship based on shaft generator converter and method thereof

Abstract

The present invention discloses a ship power control system based on an axial generator converter.

Description

Technology Field

[0001] The present invention relates to a power control system, and more specifically, to a system for controlling the power of a ship based on a shaft generator converter and a method for controlling the system. Background Technology

[0002] Recently, shaft generators are being widely installed on ships to meet increasingly stringent environmental regulations and improve fuel efficiency. Shaft generators installed on ships can be driven by the main engine. Consequently, the availability of shaft generators may be limited if the main engine operates below a certain speed or is not running (such as when berthing at a port). Additionally, adverse weather conditions can also restrict the availability of shaft generators as they alter the operating conditions of the main engine. As a result, shaft generators tend to have lower availability compared to diesel generators equipped with separate power generation engines.

[0003] On the other hand, while diesel generators equipped with separate power generation engines have the advantage of being able to operate at all times, they must operate at a constant speed to maintain a preset power frequency (e.g., 60 Hz). Consequently, they are operated at the same speed even when the onboard power consumption is low, which can lead to reduced efficiency.

[0004] Figure 1 is a simplified diagram illustrating a conventional ship power system.

[0005] The main distribution board (105) can perform the function of receiving power from various power sources that produce power and providing the received power to various loads connected to the main distribution board (105). In FIG. 1, the main distribution board (105) is a distribution board that is distinguished from the auxiliary distribution board not shown in FIG. 1, and refers to a distribution board corresponding to the power system related to the power of the ship. For example, a generator that produces power, a motor or drive for receiving power and providing rotational force to the ship's propeller, etc., may be connected to the main distribution board (105).

[0006] In FIG. 1, the shaft generator (110) can supply power to the main distribution board (105) by adjusting the variable frequency power, which changes according to the operating speed of the main engine, to the rated frequency through the converter (150). For example, the shaft generator (110) can produce variable frequency power of 5 to 30 Hz, and the converter (150) can convert the power produced by the shaft generator (110) into a fixed frequency of 60 Hz and deliver it to the main distribution board (105).

[0007] In FIG. 1, the first diesel generator (120), the second diesel generator (130), and the third diesel generator (140) each include a separate power generation engine and operate at a constant speed RPM at all times, and can supply fixed rated frequency power to the main distribution board (105). As an example, the first diesel generator (120) to the third diesel generator (140) can operate at a fixed RPM of 60 Hz.

[0008] In the conventional power system (10) illustrated in Fig. 1, shaft generators (110) or diesel generators can be driven in parallel according to the power demand within the ship, and if a problem occurs with the driving conditions of the main engine associated with the shaft generator (110), only the diesel generators can be driven. Prior art literature

[0009] 1. Japanese Registered Patent Publication No. 2632608 (Published April 25, 1997) 2. Korean Published Patent Publication No. 10-2024-0071749 (Published May 23, 2024) 3. Korean Published Patent Publication No. 10-2024-0078318 (Published June 3, 2024) The problem to be solved

[0010] The technical problem that the present invention aims to solve is to provide a ship power control system based on an axle generator converter and a control method for the system. means of solving the problem

[0011] A system according to an embodiment of the present invention for solving the above technical problem comprises: a first diesel generator; a second diesel generator; a third diesel generator; a shaft generator that supplies power to a distribution board; and a shaft generator converter that converts the power supplied to the distribution board. The shaft generator converter determines the necessity of cutting off the power supply of the shaft generator to the distribution board, and depending on the result of the determination, disconnects the shaft generator converter from the shaft generator and the shaft generator, and can connect the shaft generator converter to the second diesel generator.

[0012] In the above system, the first diesel generator and the shaft generator can supply power to the distribution board based on the first switchboard.

[0013] In the above system, the second diesel generator and the third diesel generator can supply power to the distribution board based on the second switchboard.

[0014] In the above system, the shaft generator converter can connect the second diesel generator while simultaneously disconnecting the shaft generator.

[0015] In the above system, the second diesel generator may be capable of operating at a variable frequency.

[0016] In the above system, the second diesel generator can be controlled to operate at a first RPM which is a default value, and can be operated by applying only a portion of the first RPM based on the control signal of the shaft generator converter.

[0017] In the above system, a portion of the first RPM may be a value selected from 60% to 80% of the first RPM.

[0018] A method according to another embodiment of the present invention for solving the above technical problem is a power control method for a ship comprising a first diesel generator, a second diesel generator, a third diesel generator, a shaft generator, and a shaft generator converter, wherein the shaft generator converter comprises the step of determining the necessity of cutting off the power supply of the shaft generator to a switchboard; the shaft generator converter comprises the step of disconnecting the shaft generator converter and the shaft generator according to the result of the determination; and the shaft generator converter comprises the step of connecting the shaft generator converter and the second diesel generator.

[0019] In the above method, the first diesel generator and the shaft generator can supply power to the distribution board based on the first switchboard.

[0020] In the above method, the second diesel generator and the third diesel generator can supply power to the distribution board based on the second switchboard.

[0021] In the above method, the step of connecting the second diesel generator may be to connect the second diesel generator while simultaneously disconnecting the shaft generator.

[0022] In the above method, the second diesel generator may be capable of operating at a variable frequency.

[0023] In the above method, the second diesel generator can be controlled to operate at a first RPM which is a default value, and when the shaft generator converter and the second diesel generator are connected, it can be operated by applying only a portion of the first RPM based on the control signal of the shaft generator converter.

[0024] In the above method, a portion of the first RPM may be a value selected from 60% to 80% of the first RPM.

[0025] One embodiment of the present invention may provide a computer-readable recording medium storing a program for executing the method. Effects of the invention

[0026] According to the present invention, the converter of the shaft generator can be utilized even in situations where the shaft generator of a ship cannot be used, thereby increasing the utilization of the shaft generator equipment.

[0027] In addition, according to the present invention, variable speed operation of the diesel generator is made possible by utilizing a shaft generator converter in situations where the shaft generator cannot be used during the navigation of a ship, and as a result, the operating efficiency of the diesel generator can be increased, thereby reducing fuel consumption and exhaust gas.

[0028] In addition, according to the present invention, even when a ship is anchored in a port, the diesel generator can be operated at a variable speed using a shaft generator converter, thereby increasing the operating efficiency of the diesel generator and reducing fuel consumption and exhaust gas.

[0029] In addition, according to the present invention, when two or more diesel generators are operated in parallel, more load is allocated to the diesel generator operating at a constant speed to enable continuous operation at a point where engine efficiency is high, and the remaining load is allocated to the diesel generator operating at a variable speed to enable optimal speed operation, thereby increasing the operating efficiency of the diesel generator and reducing fuel consumption and exhaust gas. Brief explanation of the drawing

[0030] Figure 1 is a simplified diagram illustrating a conventional ship power system. FIG. 2 is a diagram illustrating an exemplary power system of a ship in which a power control system according to the present invention operates. Figure 3 is a diagram that combines a block diagram and a flowchart to specifically explain the process performed by the shaft generator converter described in Figure 2. FIG. 4 is a flowchart illustrating an example of a control method according to the present invention. Specific details for implementing the invention

[0031] The present invention is capable of various modifications and may have various embodiments; specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention, and the methods for achieving them, will become clear by referring to the embodiments described below in detail together with the drawings. However, the present invention is not limited to the embodiments disclosed below but can be implemented in various forms.

[0032] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. When describing with reference to the drawings, identical or corresponding components are given the same reference numerals, and redundant descriptions thereof will be omitted.

[0033] In the following embodiments, terms such as first, second, etc. are used not in a limiting sense, but for the purpose of distinguishing one component from another component.

[0034] In the following embodiments, singular expressions include plural expressions unless the context clearly indicates otherwise.

[0035] In the following embodiments, terms such as "include" or "have" mean that the features or components described in the specification are present, and do not preclude the possibility that one or more other features or components may be added.

[0036] Where an embodiment can be implemented differently, a specific process sequence may be performed differently from the order described. For example, two processes described consecutively may be performed substantially simultaneously or proceed in the reverse order of the description.

[0037] FIG. 2 is a diagram illustrating an exemplary power system environment of a ship in which a power control system according to the present invention operates.

[0038] More specifically, the power system (20) of a ship to which the power control system according to the present invention is applied is characterized in that one shaft generator (110) and three diesel generators are connected to the main distribution board (105), and a shaft generator converter (200) according to the present invention is disposed between the shaft generator (110) and the main distribution board (105). Hereinafter, the diesel generators of FIG. 2 are to be abbreviated as the first diesel generator (120), the second diesel generator (130), and the third diesel generator (140), respectively, in order of proximity to the shaft generator (110).

[0039] The shaft generator converter (200) of FIG. 2 is configured as a dual receiving board capable of receiving power from two power sources. That is, the shaft generator converter (200) is configured so that both the shaft generator (110) and the second diesel generator (130) are connected to the shaft generator converter (200) through switching. Compared to the conventional power system (10), the power system (20) of the ship shown in FIG. 2 may be differentiated in the connection configuration between the second diesel generator (130) and the main distribution board (105), as well as in the hardware characteristics and control characteristics of the shaft generator converter (200), and this will be explained in detail in FIG. 3.

[0040] The shaft generator converter (200) according to the present invention functions not only as a converter that simply converts power, but also as a processor that receives various data, analyzes the received data, and generates control signals. For example, the shaft generator converter (200) may be a processor capable of analyzing data and generating control signals by executing programs stored in a built-in memory. The shaft generator converter (200) may be implemented as a physical device and may be implemented using at least one of ASICs (application specific integrated circuits), DSPs (digital signal processors), DSPDs (digital signal processing devices), PLDs (programmable logic devices), FPGAs (field programmable gate arrays), controllers, microcontrollers, microprocessors, and other electrical units for performing functions.

[0041] In FIG. 2, the main distribution board (105) includes a distribution board by a first switchboard (105-1) and a distribution board by a second switchboard (105-2). Power can be supplied to the distribution board by the first switchboard (105-1) by an axle generator (110) and a first diesel generator (120), and power can be supplied to the distribution board by the second switchboard (105-2) by a second diesel generator (130) and a third diesel generator (140). In FIG. 2, when the B receiving board is activated through the control of the axle generator converter (200), power produced by the second diesel generator (130) may be converted by the axle generator converter (200) and supplied to the distribution board by the first switchboard (105-1). In this case, the second diesel generator (130) can supply power to both the distribution board by the first switchboard (105-1) and the distribution board by the second switchboard (105-2).

[0042] Figure 3 is a diagram that combines a block diagram and a flowchart to specifically explain the process performed by the shaft generator converter described in Figure 2.

[0043] The shaft generator converter (200) of FIG. 3 is composed of dual power receiving boards, and depending on whether the shaft generator is operating, only one of the dual power receiving boards can be selectively connected and controlled. When the shaft generator converter (200) determines that the shaft generator (110) is in a usable state, it keeps the power of the shaft generator (110) ON, and after connecting power receiving board A included in the shaft generator converter (200) (S310), it can set control mode A (S320). In step S320, when control mode A is set in the shaft generator converter (200), setting information corresponding to control mode A can be transmitted to protection relay A included in the multiple protection relay (210) of the main distribution board. Here, the setting information corresponding to control mode A may include at least one of the following: shaft generator rated power generation capacity information (e.g., 2000kW), available power generation capacity per shaft generator operating speed (e.g., 1000kW to 2000kW), real-time shaft generator power generation capacity information per operating speed (e.g., 1000kW to 2000kW), real-time shaft generator operating speed frequency information (30Hz to 60Hz), and emergency stop message information for requesting the opening of a protective relay when an overload relative to the power generation capacity per real-time shaft generator operating speed is detected or when any one of the voltage, current, or frequency is abnormal.

[0044] When control mode A is set in step S320, the shaft generator converter (200) controls the operation of the shaft generator (110) based on the control mode A setting information (S330) so that rated power can be supplied to the main distribution board (105) (S340).

[0045] When the shaft generator converter (200) determines that the shaft generator (110) is not in a usable state, it keeps the power of the shaft generator (110) OFF, and after connecting the receiving board B included in the shaft generator converter (200) (S350), it can set control mode B (S360). In step S360, when control mode B is set in the shaft generator converter (200), setting information corresponding to control mode B can be transmitted to the protection relay B included in the multiple protection relay (210) of the main distribution board (105). Here, the setting information corresponding to control mode B may include at least one of the following: rated power generation capacity information of the second diesel generator (e.g., 1250kW), available power generation capacity per operating speed of the second diesel generator (e.g., 750kW to 1240kW), real-time power generation capacity information per operating speed of the second diesel generator (e.g., 750kW to 1240kW), real-time frequency information per operating speed of the second diesel generator (36Hz to 60Hz), and emergency stop message information for requesting the opening of a protective relay when an overload relative to the power generation capacity per operating speed of the second diesel generator is detected or when any one of the voltage, current, or frequency is abnormal.

[0046] When control mode B is set in step S360, the shaft generator converter (200) controls the operation of the second diesel generator (120) based on the control mode B setting information (S370) so that rated power can be supplied to the main distribution board (105) (S380). At this time, in order for the second diesel generator (120) to supply variable frequency power to the main distribution board (105) in step S370, it must receive diesel generator speed control information from the diesel generator control system (230), and the diesel generator speed control information may be control information generated by processing basic information generated from the power management system (220). For example, the power management system (220) may transmit information regarding the amount of power required to operate the ship and the optimal operating speed (in knots) to the diesel generator control system (230).

[0047] Below, the operation of the shaft generator converter (200) described above will be described by listing each embodiment.

[0048] In one embodiment, the power control system according to the present invention comprises: a shaft generator (110) that supplies power to a first diesel generator (120), a second diesel generator (130), a third diesel generator (140), and a main distribution board (105); and a shaft generator converter (200) that converts the power supplied to the main distribution board (105). The shaft generator converter (200) determines the necessity of cutting off the power supply of the shaft generator (110) to the main distribution board (105), and depending on the result of the determination, disconnects the shaft generator converter (200) from the shaft generator (110) and connects the shaft generator converter (200) to the second diesel generator (130). In this embodiment, determining the necessity of cutting off the power supply of the shaft generator (110) means determining the necessity of changing the power system. That is, the shaft generator converter (200) may determine that there is a need to change the power system in cases where the use of the shaft generator (110) is unnecessary because the ship is docked at or is scheduled to dock at a port, where the use of a diesel generator is more efficient than the use of the shaft generator (110) due to weather fluctuations during the operation of the ship, or where it is determined that the shaft generator (110) cannot be used otherwise (multiple conditions input by the user).

[0049] In a power control system according to one embodiment, the first diesel generator (120) and the shaft generator (110) can supply power to the main distribution board (105) based on the first switchboard (105-1).

[0050] In a power control system according to one embodiment, the second diesel generator (130) and the third diesel generator (140) can supply power to the main distribution board (105) based on the second switchboard (105-2). Through such a configuration, even if the second switchboard (105-2) fails, power supply to the first switchboard (105-1) is maintained, so that power can be stably supplied to the equipment for the overall power of the ship.

[0051] In a power control system according to one embodiment, the shaft generator converter (200) can disconnect the shaft generator (110) while simultaneously connecting the second diesel generator (130).

[0052] In a power control system according to one embodiment, the second diesel generator (130) can operate at a variable frequency.

[0053] In a power control system according to one embodiment, the second diesel generator (130) can be controlled to operate at a first RPM which is a default value, and can be operated by applying only a portion of the first RPM based on a control signal of the shaft generator converter (200).

[0054] In a power control system according to one embodiment, a portion of the first RPM of the second diesel generator (130) may be a value selected from 60% to 80% of the first RPM. For example, if the first RPM is 60Hz, the second diesel generator (130) may generate power of a frequency of 36Hz to 48Hz after being connected to the shaft generator converter (200).

[0055] The shaft generator converter (200) of the power control system according to the method stores all setting information for control mode A and control mode B, and when the second diesel generator (130) is connected to the shaft generator converter (200), information regarding the amount of power required for the operation of the ship is obtained from the power management system (220), and when the RPM of the second diesel generator (130) is calculated based on the information regarding the amount of power obtained, the second diesel generator (130) supplies power at the corresponding RPM, and the supplied power can be transmitted to the main distribution board (105).

[0056] FIG. 4 is a flowchart illustrating an example of a control method according to the present invention.

[0057] Since the method according to FIG. 4 can be implemented by the shaft generator converter (200) described in FIG. 3, the following description will be explained with reference to FIG. 2 and FIG. 3, and descriptions that overlap with those already explained will be omitted.

[0058] The shaft generator converter (200) can monitor the power demand within the ship (S410).

[0059] The shaft generator converter (200) may determine that there is a need to change the power system as a result of step S410 (S430).

[0060] If it is determined in step S430 that there is a need to change the power system, the shaft generator converter (200) may disconnect from the existing shaft generator (110) and connect a diesel generator to the shaft generator converter (200) (S450). The diesel generator connected to the shaft generator converter (200) in step S450 may be a second diesel generator (130) connected to the main distribution board (105) through the second switchboard (105-2).

[0061] The shaft generator converter (200) can optimize the entire power system of the ship according to the changed generator (S470).

[0062] According to the present invention, the converter of the shaft generator can be utilized even in situations where the shaft generator of a ship cannot be used, thereby increasing the utilization of the shaft generator equipment.

[0063] In addition, according to the present invention, variable speed operation of the diesel generator is made possible by utilizing a shaft generator converter in situations where the shaft generator cannot be used during the navigation of a ship, and as a result, the operating efficiency of the diesel generator can be increased, thereby reducing fuel consumption and exhaust gas.

[0064] In addition, according to the present invention, even when a ship is anchored in a port, the diesel generator can be operated at a variable speed using a shaft generator converter, thereby increasing the operating efficiency of the diesel generator and reducing fuel consumption and exhaust gas.

[0065] In addition, according to the present invention, when two or more diesel generators are operated in parallel, more load is allocated to the diesel generator operating at a constant speed to enable continuous operation at a point where engine efficiency is high, and the remaining load is allocated to the diesel generator operating at a variable speed to enable optimal speed operation, thereby increasing the operating efficiency of the diesel generator and reducing fuel consumption and exhaust gas.

[0066] The embodiments according to the present invention described above may be implemented in the form of a computer program that can be executed through various components on a computer, and such a computer program may be recorded on a computer-readable medium. In this case, the medium may include a magnetic medium such as a hard disk, a floppy disk, and a magnetic tape, an optical recording medium such as a CD-ROM and a DVD, a magneto-optical medium such as a floptical disk, and a hardware device specifically configured to store and execute program instructions, such as a ROM, RAM, or flash memory.

[0067] Meanwhile, the above-mentioned computer program may be one specifically designed and configured for the present invention, or one known and available to those skilled in the art of computer software. Examples of computer programs may include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc.

[0068] The specific embodiments described in this invention are examples and do not limit the scope of the invention in any way. For the sake of brevity of the specification, descriptions of prior electronic configurations, control systems, software, and other functional aspects of said systems may be omitted. Additionally, the connections of lines or connecting members between components shown in the drawings are illustrative of functional connections and / or physical or circuit connections, and may be replaced or additionally represented as various functional connections, physical connections, or circuit connections in actual devices. Furthermore, unless specifically stated as “essential,” “importantly,” etc., a component may not be strictly necessary for the application of the invention.

[0069] In the specification of the present invention (particularly in the claims), the use of the term “above” and similar descriptive terms may be in both singular and plural. Furthermore, where a range is described in the present invention, it is to include the invention to which individual values ​​belonging to said range are applied (unless otherwise stated), and is equivalent to describing each individual value constituting said range in the detailed description of the invention. Finally, regarding the steps constituting the method according to the present invention, unless explicitly stated in order or otherwise stated, said steps may be performed in a suitable order. The present invention is not necessarily limited by the order in which said steps are described. The use of all examples or exemplary terms (e.g., etc.) in the present invention is merely for the purpose of describing the present invention in detail, and the scope of the present invention is not limited by said examples or exemplary terms unless limited by the claims. Furthermore, those skilled in the art will understand that various modifications, combinations, and changes may be made according to design conditions and factors within the scope of the claims or equivalents to which they are added. Explanation of the symbols

[0070] 105: Main distribution panel 110: Shaft generator 120: 1st Diesel Generator 130: 2nd Diesel Generator 140: 3rd diesel generator 200: Shaft generator converter

Claims

Claim 1 A ship power control system based on a shaft generator converter, comprising: a first diesel generator; a second diesel generator; a third diesel generator; a shaft generator that supplies power to a switchboard; and a shaft generator converter that converts the power supplied to the switchboard. The shaft generator converter determines whether there is a need to change the ship's power system, and, depending on the result of the determination, disconnects the shaft generator converter from the shaft generator and connects the shaft generator converter to the second diesel generator. Claim 2 In claim 1, the first diesel generator and the shaft generator supply power to the distribution board based on the first switchboard, forming a shaft generator converter-based ship power control system. Claim 3 In paragraph 2, the shaft generator converter-based ship power control system, wherein the second diesel generator and the third diesel generator supply power to the distribution board based on the second switchboard. Claim 4 In claim 1, the shaft generator converter is a shaft generator converter-based ship power control system that disconnects the shaft generator while simultaneously connecting the second diesel generator. Claim 5 In paragraph 1, the second diesel generator is a shaft generator converter-based ship power control system capable of operating at a variable frequency. Claim 6 A ship power control system based on a shaft generator converter according to claim 1, wherein the second diesel generator is controllable to operate at a first RPM which is a default value, and can be operated by applying only a portion of the first RPM based on a control signal of the shaft generator converter. Claim 7 A shaft generator converter-based ship power control system according to claim 6, wherein a portion of the first RPM is a value selected from 60% to 80% of the first RPM. Claim 8 A method for controlling power of a ship comprising a first diesel generator, a second diesel generator, a third diesel generator, a shaft generator, and a shaft generator converter, wherein the shaft generator converter determines whether there is a need to change the ship's power system and determines the need to cut off the power supply of the shaft generator to the distribution board; the shaft generator converter disconnects the shaft generator converter and the shaft generator according to the result of the determination; and the shaft generator converter connects the shaft generator converter and the second diesel generator. Claim 9 A method for controlling the power of a ship according to claim 8, wherein the first diesel generator and the shaft generator supply power to the distribution board based on the first switchboard. Claim 10 A method for controlling power of a ship according to claim 9, wherein the second diesel generator and the third diesel generator supply power to the distribution board based on the second switchboard. Claim 11 In claim 8, the step of connecting the second diesel generator is to connect the second diesel generator while simultaneously disconnecting the shaft generator, a method for controlling the power of a ship. Claim 12 In paragraph 8, the above-mentioned second diesel generator is capable of operating at a variable frequency, a method for controlling the power of a ship. Claim 13 A method for controlling the power of a ship according to claim 8, wherein the second diesel generator is controllable to operate at a first RPM which is a default value, and when the shaft generator converter and the second diesel generator are connected, the second diesel generator is capable of operating by applying only a portion of the first RPM based on the control signal of the shaft generator converter. Claim 14 A method for controlling the power of a ship according to claim 13, wherein a portion of the first RPM is a value selected from 60% to 80% of the first RPM. Claim 15 A computer-readable recording medium storing a program for executing the method according to paragraph 8.

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