KR102305883B1 - Power management system and ship having the same - Google Patents

Abstract

The present invention relates to an electric power control system and a ship having the same, in a system for controlling electric power of a ship having a liquefied gas storage tank for storing boil-off gas, provided in the ship and supplied to a generator for generating electric power from boil-off gas a power generation amount determining unit for determining the power generation potential of the generator based on the amount of boil-off gas; an amount of power determining unit for determining the amount of power required of the vessel; and a control unit provided outside of the ship and controlling an external power source that transmits power to the ship in consideration of the amount of power available and the amount of power required.

Description

A power control system and a ship having the same {Power management system and ship having the same}

The present invention relates to a power control system and a ship having the same.

A ship is a means of transport that carries a large amount of minerals, crude oil, natural gas, or thousands of containers or more and sails the ocean. move through

Such a ship generates thrust by driving an engine or a gas turbine, etc. In this case, the engine uses oil fuel such as gasoline or diesel to move the piston so that the crankshaft is rotated by the reciprocating motion of the piston, and the shaft connected to the crankshaft is rotated to drive the propeller, while the gas turbine burns fuel with compressed air, and uses the temperature/pressure of the combustion air to rotate turbine blades to generate power and transmit power to the propeller.

However, recently, an LNG fuel supply method in which LNG is used as a fuel to drive a consumer such as an engine or a turbine is used in an LNG carrier that transports liquefied natural gas, a type of liquefied gas, and LNG is a clean fuel. And since the reserves are more abundant than petroleum, the method of using LNG as a fuel for consumers is being expanded to other vessels other than LNG carriers.

However, when a ship that implements propulsion or power generation using LNG is docked on land, it is common that the power demander in the ship is operated by receiving power from the land. ) is burned and discarded by a gas combustion unit (GCU).

Therefore, in the conventional case, boil-off gas cannot be utilized and is simply discarded in a state where a vessel using LNG is docked, causing environmental pollution or wasting costs. Therefore, it is urgent to seek a solution.

The present invention was created to solve the problems of the prior art as described above, and an object of the present invention is to control the power generation using boil-off gas and the supply of external power in a state in which a ship is docked on land, thereby contamination of the environment. To provide a power control system that can solve the problem and significantly reduce costs, and a ship having the same.

The power control system according to an aspect of the present invention is a system for controlling the power of a ship having a liquefied gas storage tank for storing boil-off gas, the amount of boil-off gas supplied to a generator provided in the ship and generating electric power from boil-off gas Based on the power generation amount determining unit for determining the power generation potential of the generator; an amount of power determining unit for determining the amount of power required of the vessel; and a control unit provided outside of the ship and controlling an external power source that transmits power to the ship in consideration of the amount of power available and the amount of power required.

Specifically, the external power source may be a land power source that transmits power to the ship when the ship is anchored.

Specifically, the control unit may control the external power source so that the external power supply transmits power to the ship by a shortfall excluding the power generation possible amount from the required power amount.

Specifically, the control unit, according to the magnitude of the amount of power available and the amount of power required, may alternatively implement power transmission by the external power source or power generation by the generator so that the amount of power required is satisfied.

Specifically, it further comprises a flow meter for measuring the amount of boil-off gas transferred from the liquefied gas storage tank to the generator, the generation amount determining unit, based on the measurement value of the flow meter, it is possible to determine the amount of power generation possible for each hour of the generator.

Specifically, it further includes a pressure gauge for measuring the pressure of the liquefied gas storage tank, the power generation amount determining unit, based on the measured value of the pressure gauge, estimating the amount of boil-off gas may determine the power generation potential of the generator.

Specifically, the amount of BOG estimated according to the measurement value of the pressure gauge may be converted into the BOG amount for each hour delivered to the generator to determine the amount of power generation possible for each hour of the generator.

Specifically, the power amount determining unit may determine the amount of power required by time of the vessel, and the control unit may control the external power source in consideration of the amount of power available for each time and the required amount of power.

A ship according to an aspect of the present invention is characterized in that it has the power control system.

Specifically, it may be a container ship mounted with a container including a reefer container.

Specifically, the external power source may deliver power to the refrigerating container when anchored.

The power control system according to the present invention and a ship having the same, implement power generation using boil-off gas generated in the ship when the ship is docked on land, but perform power generation using boil-off gas and power transmission from an external power source By linking and controlling each other, the efficiency of energy operation can be maximized.

1 is a side view of a ship according to an embodiment of the present invention.
2 is a conceptual diagram of a power control system according to an embodiment of the present invention.
3 is a flowchart illustrating a process of a power control system according to an embodiment of the present invention.

The objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and preferred embodiments taken in conjunction with the accompanying drawings. In the present specification, in adding reference numbers to the components of each drawing, it should be noted that only the same components are given the same number as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Hereinafter, the liquefied gas may be LPG, LNG, ethane, ammonia, etc., but may refer to any material that is transported in a liquid state by cooling, but has a lower boiling point than room temperature and can evaporate to a gaseous state at room temperature.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention is intended to include a power control system and a ship having the same, in which case the ship is a general merchant ship such as a liquefied gas carrier carrying liquefied gas or a container ship carrying containers, as well as offshore plants such as FLNG and FSRU. let me know However, hereinafter, for convenience, the description is limited to a case in which the power control system of the present invention is loaded on a container ship.

1 is a side view of a ship according to an embodiment of the present invention, FIG. 2 is a conceptual diagram of a power control system according to an embodiment of the present invention, and FIG. 3 is a process of the power control system according to an embodiment of the present invention is a flowchart showing For reference, in FIG. 2 , a solid line indicates fluid transmission, a dotted line indicates signal transmission, and a dashed-dotted line indicates power transmission.

1 to 3 , a ship 1 according to an embodiment of the present invention may be loaded with a plurality of containers 15 including a reefer container 15a, for example, as a container ship. In this case, the refrigerating container 15a is a configuration that consumes power to lower the internal temperature, unlike the general container 15 , and may be a power demander.

The vessel 1 includes a liquefied gas storage tank 12 for storing liquefied gas. The liquefied gas storage tank 12 may store cryogenic liquefied gas having a lower boiling point than room temperature in a liquid phase, and may have a thermal insulation structure to suppress evaporation of the liquefied gas.

However, in the liquefied gas storage tank 12, boil-off gas may be generated as the liquefied gas is naturally vaporized, and thus the internal pressure of the liquefied gas storage tank 12 may increase. That is, the internal pressure of the liquefied gas storage tank 12 may be used as an index indicating the amount of boil-off gas generated in the liquefied gas storage tank 12 .

To this end, the liquefied gas storage tank 12 may be provided with a pressure gauge 12a for measuring the pressure of the liquefied gas storage tank 12 . The pressure of the liquefied gas storage tank 12 measured by the pressure gauge 12a may be converted into an amount of boil-off gas in the liquefied gas storage tank 12 and utilized for controlling the power control system 10 to be described later.

The liquefied gas storage tank 12 may be provided in the ship as shown in the drawing, and for example, may be provided in the rear of the cabin from the front of the engine room. Of course, the arrangement of the liquefied gas storage tank 12 in the ship 1 of the present invention is not limited to the above, and the liquefied gas storage tank 12 is provided directly below the cabin or provided on the upper deck to be exposed to the outside. may be

The liquefied gas storage tank 12 may be provided in a Type B type and disposed on the ship, or may be provided in a Type C shape and disposed outside the ship, but the shape or arrangement of the liquefied gas storage tank 12 in the present invention is not particularly limited. can

The vessel 1 may include a generator 11 for generating electric power using liquefied gas and/or boil-off gas stored in the liquefied gas storage tank 12, or the vessel 1 may include liquefied gas and/or Alternatively, it may include an engine (not shown) for propelling the vessel 1 by rotating a propeller by generating a rotational force with boil-off gas.

That is, the ship 1 uses a shaft propulsion method in which a propeller is connected by rotating a shaft to be propelled by using an engine, or an electric motor (not shown) rotating the propeller is provided and the power generated from the generator 11 . It is also possible to use an electric propulsion method that uses an electric motor to drive it.

However, no matter which propulsion method the ship 1 uses, the generator 11 may be essentially provided in order to supply power to various power demanders provided in the ship. That is, the ship 1 supplies power to the inside of the ship using the generator 11 and uses an electric propulsion method to implement propulsion, or supplies power to the inside of the ship using the generator 11 and uses the engine for propulsion. A shaft propulsion method to implement is available.

A gas supply line 13 may be provided from the liquefied gas storage tank 12 to the generator 11 . The gas supply line 13 is a pipe for delivering cryogenic liquefied gas or boil-off gas to the generator 11 , and has a double structure to implement thermal insulation.

The gas supply line 13 may be provided with a compressor 14 for compressing the boil-off gas transferred from the liquefied gas storage tank 12 to the generator 11 . In this case, the gas supply line 13 may be the boil-off gas supply line 13 .

The compressor 14 is configured to compress the boil-off gas in order to increase the pressure of the boil-off gas generated in the liquefied gas storage tank 12 to the pressure required by the generator 11 (for example, around 10 bar), and a plurality of compressors 14 ) is arranged in series on the gas supply line 13, it is possible to compress the boil-off gas in multiple stages.

A flow meter 13a may be provided downstream of the compressor 14 in the gas supply line 13 . The flow meter 13a measures the amount of BOG delivered to the generator 11 after being compressed through the compressor 14 .

The measured value measured by the flow meter 13a means the flow rate of BOG delivered to the generator 11 by time, whereas the measured value measured by the aforementioned pressure gauge 12a is the liquefied gas storage tank 12 . The dimension of the measured value is different because it represents the amount of boil-off gas stored in the system itself.

Therefore, as will be described later, when the power control system 10 intends to use the measured value of the pressure gauge 12a, a process of converting the measured value of the pressure gauge 12a into units of time may be required.

Hereinafter, the power control system 10 according to an embodiment of the present invention will be described in detail with reference to FIG. 2 .

The power control system 10 mounted on the ship 1 described above is a system for controlling the power of the ship 1 having a liquefied gas storage tank 12 for storing liquefied gas and boil-off gas, and a power generation amount determining unit ( 100 ), an amount of power determining unit 200 , and a control unit 300 .

The power generation amount determining unit 100 grasps the power generation potential of the generator 11 based on the BOG supplied to the generator 11 that is provided in the ship 1 and generates electric power from BOG. At this time, the generator 11 is provided to supply electric power to the onboard power demander as mentioned above, but may additionally take charge of propulsion of the ship 1 .

The generation amount determining unit 100 may check the amount of BOG supplied to the generator 11 using the flow meter 13a and/or the pressure gauge 12a. As an example, when the generation amount determining unit 100 uses the flow meter 13a, the measured value of the flow meter 13a may be the amount of BOG compressed by the compressor 14 and supplied to the generator 11 as described above, so the generation amount The grasper 100 may grasp the amount of power generation possible for each hour of the generator 11 based on the measured value of the flow meter 13a.

On the other hand, when the generation amount determining unit 100 uses the pressure gauge 12a, the generation amount determining unit 100 may estimate the amount of BOG through the measurement value of the pressure gauge 12a. At this time, the internal pressure of the liquefied gas storage tank 12 and the amount of boil-off gas may be matched with each other using table data, etc. However, the amount of liquefied gas stored in the liquefied gas storage tank 12 may affect the internal pressure, A level gauge (not shown) is provided in the liquefied gas storage tank 12 , and the generation amount determining unit 100 measures the amount of boil-off gas through the internal pressure of the liquefied gas storage tank 12 while considering the level of the liquefied gas storage tank 12 . can figure out

At this time, the detected BOG may not be a value in units of time, unlike the measured value of the flow meter 13a, and the generation amount determining unit 100 converts the estimated BOG to the hourly BOG delivered to the generator 11. can do. That is, the generation amount determining unit 100 transmits the BOG calculated through the pressure gauge 12a to the generator 11 in consideration of the specifications of the gas supply line 13 , the compressor 14 , the generator 11 , and the like. It can be replaced by the amount of BOG per hour, and in the replacement process, table data in which the amount of BOG delivered to the generator 11 is measured by time according to the amount of BOG stored in the liquefied gas storage tank 12 may be used, but in specific The calculation method is not particularly limited.

Alternatively, when the internal pressure of the liquefied gas storage tank 12 exceeds a predetermined pressure range by the pressure gauge 12a, the boil-off gas may be automatically discharged to protect the liquefied gas storage tank 12, at this time the compressor According to the load of (14), the amount of BOG delivered to the generator (11) by time may be calculated.

That is, the generation amount determining unit 100 may use any data capable of calculating the amount of BOG delivered to the generator 11, such as the flow meter 13a, the pressure gauge 12a, and the load of the compressor 14, and the generation amount data is Based on the amount of BOG transmitted to the generator 11 by time, the amount of power generation possible for each hour of the generator 11 may be grasped.

The electric energy grasping unit 200 grasps the required electric energy of the ship 1 . The amount of power required of the ship 1 may be instantaneous power and a value in units of time. That is, the power amount determining unit 200 may determine the amount of power required for each hour of the vessel 1 . Therefore, as will be described later, in order to compare the amount of power required with the amount of power available, the generation amount determining unit 100 may match the amount of power generation with the same unit as the amount of power required.

The amount of power required by the power amount determining unit 200 may be generated when the ship 1 is moored, not when it is operating. Since this embodiment is used in the process of receiving power from an external power source 20 provided on land, etc. when the ship 1 is docked in a port, etc., the power amount determining unit 200 is the amount of power required when the ship 1 is anchored. can figure out

When the ship 1 is, for example, a container ship, the amount of power required to be grasped by the power amount determining unit 200 is generated by the cabin, etc., but may be mainly generated by the reefer container 15a or the like. That is, in this embodiment, power is transmitted from the external power source 20 to the refrigeration container 15a when the container ship is anchored, so that the refrigerated cargo can be stably stored.

The control unit 300 may control the external power source 20 that is provided outside the ship 1 and transmits power to the ship 1 in consideration of the amount of power available and the amount of power required. In this case, the external power source 20 may be a land power source that transmits power to the ship 1 when the ship 1 is anchored, and the power transmitted from the external power source 20 to the ship 1 is mostly the ship (1). ) that can be delivered to the refrigerating container (15a) mounted on is as mentioned above.

Of course, the external power source 20 may not be a land power source but a power source provided on another ship or offshore structure, etc. It may also be delivered to handling equipment (not shown). That is, it should be noted that in the present invention, the type, shape, location, and use of the power supplied from the external power source 20 in the ship 1 are not particularly limited in the present invention.

The control unit 300 compares the amount of power available to the amount of power required. At this time, the amount of power required is a value that appears in units of time in terms of instantaneous power, and in consideration of this, the generation amount determining unit 100 also grasps the amount of generation possible by time, and the control unit 300 considers the amount of power available and the amount of power required for each time and considers the external power source. (20) can be controlled.

Specifically, when the amount of power available exceeds the required amount of electricity, power is generated and used by the generator 11 using the boil-off gas in the ship 1, so that the electricity demander in the ship 1 without burning the boil-off gas While satisfying the needs of the external power supply 20 can be prevented from operating unnecessarily.

On the other hand, if the amount of available power does not reach the required amount of power, even if the generator 11 is operated using boil-off gas in the ship 1, the power demander may not be properly operated. By driving the external power source 20, it is possible to satisfy the demand of the power demand in the ship (1).

In this case, the control unit 300 may control the external power source 20 so that the external power source 20 delivers power to the ship 1 by the shortfall excluding the amount of power available from the required power. That is, the control unit 300 causes the operation of the external power source 20 to be operated in connection with the amount of BOG in the ship 1, thereby preventing BOG generated in the ship 1 from being discarded while the external power source 20 is operated. load can be reduced.

Alternatively, the control unit 300 may alternatively implement power transmission by the external power source 20 or power generation by the generator 11 according to the magnitude of the amount of power available and the amount of power required so that the amount of power required is satisfied. This is to minimize the repeated on/off of the operation of the external power supply 20 when comparing the amount of power available and the amount of power required.

Hereinafter, a process of the power control system 10 of the present embodiment will be described based on FIG. 3 .

Referring to FIG. 3 , the BOG amount may be grasped first, and in this case, the BOG amount may mean the BOG amount for each hour detected by the flow meter 13a or may mean the BOG amount detected by the pressure gauge 12a. Of course, when the amount of boil-off gas is detected by the pressure gauge 12a, the process of converting the BOG in units of time may be performed as described above.

Thereafter, the generation amount determining unit 100 may determine the hourly generation potential of the generator 11 by using the hourly BOG transmitted to the generator 11 . Of course, together with the grasp of the amount of power generation, in this embodiment, the amount of power required for each hour in the vessel 1 may be grasped through the electric power determination unit 200 .

Thereafter, the control unit 300 may compare the amount of power available and the amount of power required, and if the amount of power available is sufficient, it may generate electricity from boil-off gas to satisfy the required amount of power. However, if the amount of available power is insufficient compared to the required amount of power, the external power source 20 may be used to supplement the shortfall amount from the external power source 20 .

Of course, as described above, the control unit 300 may satisfy the required amount of power by using only the external power source 20 when the amount of power available is less than the required amount of power.

As such, in this embodiment, while the vessel 1 is moored while using the external power source 20 to ensure the operation of the power demander within the vessel 1, the vessel 1 depends entirely on the external power source 20. ), by synchronizing the operation of the external power source 20 according to the amount of BOG in the vessel 1 to solve the problem that BOG generated within the vessel is thrown away, while reducing BOG being discarded, the external power source (20) can lower the load.

It goes without saying that the present invention is not limited to the embodiments described above, and combinations of at least some of the contents of the embodiments and known techniques may be included as other embodiments.

In the above, the present invention has been described focusing on the embodiments of the present invention, but this is merely an example and does not limit the present invention. It will be appreciated that various combinations or modifications and applications not illustrated in the embodiments are possible within the scope. Accordingly, descriptions related to variations and applications that can be easily derived from the embodiments of the present invention should be interpreted as being included in the present invention.

1: Vessel 10: Power Control System
11: Generator 12: Liquefied gas storage tank
12a: pressure gauge 13: gas supply line
13a: flowmeter 14: compressor
15: container 15a: reefer container
100: generation amount determination unit 200: electricity amount determination unit
300: control unit 20: external power

Claims (11)

In the system for controlling the power of a ship having a liquefied gas storage tank for storing boil-off gas,
a generation amount determining unit provided in the ship and configured to determine the amount of power generation possible of the generator based on the amount of BOG supplied to a generator that generates electric power from BOG;
an amount of power determining unit for determining the amount of power required of the vessel; and
In consideration of the amount of power generation and the amount of power required, it is provided outside the ship and includes a control unit for controlling an external power source that transmits power to the ship,
The control unit is
When the amount of power available is greater than or equal to the required amount of power, the external power source is controlled not to operate, and when the amount of power that can be generated does not reach the required amount of power, the external power source is operated in response to a shortage excluding the amount of power available from the required amount of power. Thus, the power control system, characterized in that for synchronizing the operation of the external power source according to the amount of power generation possible. According to claim 1, wherein the external power source,
A power control system, characterized in that the ship is an onshore power source that transmits power to the ship when the ship is anchored. delete According to claim 1, wherein the control unit,
Power control system, characterized in that by implementing power transmission by the external power source or power generation by the generator alternatively according to the magnitude of the power generation possible amount and the required power amount, the required power amount is satisfied. The method of claim 1,
Further comprising a flow meter for measuring the amount of boil-off gas transferred from the liquefied gas storage tank to the generator,
The power generation amount determining unit, Power control system, characterized in that for determining the amount of power generation by time of the generator based on the measured value of the flow meter. The method of claim 1,
Further comprising a pressure gauge for measuring the pressure of the liquefied gas storage tank,
The power generation amount determining unit, the power control system, characterized in that for estimating the amount of boil-off gas based on the measured value of the pressure gauge to grasp the power generation possible amount of the generator. 7. The method of claim 6,
Power control system, characterized in that the amount of BOG estimated according to the measured value of the pressure gauge is converted into the BOG amount for each hour delivered to the generator to determine the amount of power generation possible for each hour of the generator. The method of claim 5 or 7, wherein the power amount determining unit,
Determine the amount of power required by the hour of the vessel,
The control unit, the power control system, characterized in that for controlling the external power source in consideration of the amount of power generation possible and the required power for each time. A ship having the power control system according to any one of claims 1, 2 and 4 to 7. 10. The method of claim 9,
A ship characterized in that it is a container ship on which a container including a reefer container is mounted. 11. The method of claim 10, wherein the external power source,
A ship, characterized in that for transmitting power to the reefer container when anchored.

Images