KR102586062B1 - DC distribution system and method therefor - Google Patents

Abstract

Generator, fuel cell, battery, AC/DC converter connected to the generator, first DC/DC converter connected to the fuel cell, second DC/DC converter connected to the battery, AC/DC converter, first DC/DC converter and second A control unit connected to the output of the DC/DC converter, an AC/DC converter, a DC bus connected to the outputs of the first DC/DC converter and the second DC/DC converter and connected to the control unit, a DC/AC converter connected to the DC bus, and a DC/DC converter connected to the DC bus. It includes a load connected to the AC converter, and when the power supplied from the battery is less than a predetermined standard power, the control unit compares the amount of power that can be supplied from the generator and the fuel cell, and either the generator or the fuel cell supplies power to the DC bus. A DC distribution system and distribution method that controls to do so are disclosed.

Description

DC distribution system and method therefor}

The present invention relates to a DC power distribution system and distribution method for a ship where, when there is a problem with the power supplied from the battery, the condition of the generator and fuel cell is compared and the power source in relatively good condition supplies power.

A fuel cell is a device that generates electrical energy by electrochemically reacting fuel and oxidizer. This chemical reaction is carried out by a catalyst within the catalyst layer, and generally, continuous power generation is possible as long as fuel is continuously supplied.

The fuel cell system is a power generation system that directly converts the chemical reaction energy of hydrogen and oxygen contained in hydrocarbon-based materials such as LNG, LPG, methanol, ethanol, and gasoline into electrical energy. The air electrode contains the reduction reaction of oxygen, which is an oxidizing agent, and At the anode, an electrochemical reaction occurs in which the oxidation reaction of hydrogen, the fuel, occurs, generating electricity, heat, and water.

Recently, the shipping industry has been actively developing eco-friendly ship technology using fuel cells. By using electricity as a power source using fuel cells, there is an advantage in significantly reducing carbon dioxide emissions compared to ships propelled by existing fossil fuels.

Currently, ships that operate only with fuel cells and batteries have been developed and are in operation, but it is difficult to apply fuel cells and batteries alone to large ships. Additionally, if there is a problem with the battery, there is a problem that power supply may be disrupted.

The present invention solves the above problems, by adding an engine generator to a power supply source composed of fuel cells and batteries for application to large ships, and by adding an engine generator, a ship's power distribution system and distribution system to improve the power supply efficiency of the engine generator, fuel cells, and batteries. Provides a distribution method in the system.

According to an embodiment of the present invention to solve the above technical problem, a DC distribution system includes a generator; fuel cell; battery; an AC/DC converter connected to the generator, a first DC/DC converter connected to the fuel cell, and a second DC/DC converter connected to the battery; a control unit connected to outputs of the AC/DC converter, the first DC/DC converter, and the second DC/DC converter; a DC bus connected to the outputs of the AC/DC converter, the first DC/DC converter, and the second DC/DC converter, and connected to the control unit; A DC/AC converter connected to the DC bus; and a load connected to the DC/AC converter, wherein the control unit compares the amount of power that can be supplied from the generator and the fuel cell when the power supplied from the battery is less than a predetermined reference power, and compares the amount of power that can be supplied by the generator and the fuel cell. One of them controls to supply power to the DC bus.

The second DC/DC converter may be a bidirectional converter.

After comparing the amount of power that can be supplied, the controller may control the other of the generator and the fuel cell to charge the battery.

When the battery is fully charged, the battery can supply power to the DC bus again.

The control unit may be further connected to outputs of the generator, the fuel cell, and the battery.

According to another embodiment of the present invention for solving the above technical problem, a DC power distribution method includes the steps of a DC distribution system including a generator, a fuel cell, a battery, a DC bus, and a load detecting power supplied from the battery; When the power supplied from the battery is less than a predetermined reference power, a DC distribution system comparing the amount of power that can be supplied by the generator and the fuel cell; And as a result of comparing the amount of available power, the DC distribution system controls one of the generator and the fuel cell to supply power to the load through the DC bus.

The present invention further provides an engine generator for supplying power to a ship equipped with a fuel cell, and provides a DC power distribution system and distribution method for efficient power supply to the engine generator, fuel cell, and battery.

1 is a block diagram of a DC distribution system according to an embodiment of the present invention.
Figure 2 is a block diagram of a DC distribution system according to another embodiment of the present invention.
Figure 3 is a flowchart of a DC power distribution method according to an embodiment of the present invention.

Preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

In describing the embodiments of the present specification, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present specification, the detailed description will be omitted.

In the present invention, the description of “including” a specific configuration does not exclude configurations other than the configuration, and means that additional configurations may be included in the practice of the present invention or the scope of the technical idea of the present invention.

Additionally, the components appearing in the embodiments of the present invention are shown independently to show different characteristic functions, and this does not mean that each component is comprised of separate hardware or a single software component. That is, each component is listed and included as a separate component for convenience of explanation, and at least two of each component can be combined to form one component, or one component can be divided into a plurality of components to perform a function, and each of these components can perform a function. Integrated embodiments and separate embodiments of the constituent parts are also included in the scope of the present invention as long as they do not deviate from the essence of the present invention.

Additionally, some components may not be essential components that perform essential functions in the present invention, but may simply be optional components to improve performance. The present invention can be implemented by including only essential components for implementing the essence of the present invention excluding components used only to improve performance, and a structure including only essential components excluding optional components used only to improve performance. is also included in the scope of rights of the present invention.

Additionally, in this specification, detailed descriptions of well-known functions and configurations that may obscure the gist of the present invention will be omitted.

1 is a block diagram of a DC distribution system according to an embodiment of the present invention.

Referring to Figure 1, the DC distribution system includes a generator 110, a fuel cell 120, a battery 130, an AC/DC converter 141, a first DC/DC converter 142, and a second DC/DC converter. (143), control unit 150, DC bus 160, DC/AC converters (171, 172), and loads (181, 182).

The DC distribution system uses a generator 110, a fuel cell 120, and a battery 130 as a power generation module that converts fuel into power and delivers it to one or more power distribution modules.

The generator 110 produces power for ship propulsion and ship operation and supplies it to the switchboard. The generator 110 includes a turbine generator, a diesel generator, an engine generator, a superconducting generator, etc., and an engine generator is preferred in the present invention.

The fuel cell 120 can produce power by using hydrogen as a fuel and converting chemical energy into electrical energy through an electrochemical reaction with oxygen. Recently, liquid fuels such as LNG or methanol are being developed as the main fuel for the fuel cell 120. The fuel cell 120 can solve the problem of air pollution caused by exhaust gases, and is currently being widely applied due to the need to store a lot of fuel in a limited space, such as on ships.

The battery 130 can be charged through the generator 110 or the fuel cell 120, and can supply power to various loads through the DC bus 160.

The AC/DC converter 141 is connected to the output terminal of the generator 110. The AC/DC converter 141 converts the AC voltage output from the generator 110 into DC voltage and transmits it to the DC bus 160.

The first DC/DC converter 142 is connected to the output terminal of the fuel cell 120. The first DC/DC converter 142 can boost or reduce the DC voltage output from the fuel cell 120 and supply power to various loads through the DC bus 160.

The second DC/DC converter 143 is connected to the output terminal of the battery 130. The second DC/DC converter 143 can boost or reduce the DC voltage output from the battery 130 and supply power to various loads through the DC bus 160.

In one embodiment of the present invention, the second DC/DC converter 143 is a bidirectional converter. The second DC/DC converter 143 can charge the battery 130 by transferring power supplied from the generator 110 or the fuel cell 120 to the battery 130.

The output of the generator 110, fuel cell 120, and battery 130 is output to the DC bus ( 160). There is no limit to the voltage at which the DC bus 160 can operate.

In one embodiment of the present invention, the control unit 150 is connected to the outputs of the AC/DC converter 141, the first DC/DC converter 142, and the second DC/DC converter 143, and the DC bus 160 ) is connected to.

In one embodiment of the present invention, when there is a problem with the power supplied from the battery 130, the control unit 150 compares the amount of power that can be supplied by the generator 110 and the fuel cell 120, and operates the generator 110 and the fuel cell 120. Any one of the fuel cells 120 is controlled to supply power to the DC bus. In one embodiment of the present invention, when a problem occurs with the power supplied to the battery 110, the supplied power is less than a predetermined reference power (in other words, when the SOC is low) or the second DC/DC converter 143 ) is broken.

Specifically, after comparing the amount of power that can be supplied, the control unit 150 controls the other of the generator 110 and the fuel cell 120 to supply power to charge the battery 130. For example, when the amount of power that can be supplied by the generator 110 is greater than the amount of power that can be supplied by the fuel cell 120, the generator 110 supplies power to the load through the DC bus instead of the battery 130, and the fuel cell ( 120) is controlled so that power is supplied to the battery 130 through the second DC/DC converter.

Then, when the battery 130 is fully charged, the control unit 150 blocks the power supplied to the battery 130 from the generator 110 or the fuel cell 120, and the battery 130 is connected to the load through the DC bus. Control to supply power.

According to another embodiment of the present invention, the control unit 150 may be directly connected to the output of the generator 110, the fuel cell 120, and the battery 130.

Figure 2 is a block diagram of a DC distribution system according to an embodiment of the present invention.

Referring to FIG. 2, the control unit 150 is connected to the outputs of the generator 110, the fuel cell 120, and the battery 130, respectively, and the AC/DC converter 141 and the first DC/DC converter 142. ) and is also connected to the second DC/DC converter 143.

When connected as shown in FIG. 2, if there is a problem with the power supplied from the generator 110, the control unit 150 can detect whether the generator 110 or the AC/DC converter 141 has a problem, If there is a problem with the power supplied from the fuel cell 120, it is possible to detect whether there is a problem with the fuel cell 120 or the first DC/DC converter 142, and the power supplied from the battery 130 If there is a problem, it can be detected whether the battery 130 or the second DC/DC converter 143 has a problem.

In this case, the control unit 150 can bypass the output of the generator 110, fuel cell 120, and battery 130 if there is a problem with the converters. For example, if the first DC/DC converter 142 breaks down, the control unit 150 can bypass the output of the fuel cell 120 to the second DC/DC converter 143.

Figure 3 is a flowchart of a DC power distribution method according to an embodiment of the present invention.

Referring to FIG. 3, in step 310, a DC distribution system including a generator, fuel cell, battery, DC bus, and load detects power supplied from the battery.

In step 320, when the power supplied from the battery is less than a predetermined reference power, the DC distribution system compares the amount of power that can be supplied by the generator and the fuel cell. The amount of power that can be supplied refers to the amount of spare power excluding the amount of power currently supplied by the generator and fuel cell.

The DC distribution system can compare the amount of power that can be supplied by the generator and the amount of power that can be supplied by the fuel cell with a predetermined reference power.

When a problem occurs with the power supplied to the battery 110, the supplied power is less than a predetermined reference power (in other words, the SOC is low) or the second DC/DC converter 143 is broken.

In step 330, as a result of comparing the amount of power that can be supplied, the DC distribution system controls one of the generator and the fuel cell to supply power to the load through the DC bus.

In the DC distribution system, any one of the amount of power that can be supplied by a generator or the amount of power that can be supplied by a fuel cell exceeds a predetermined standard power can supply power to the load through the DC bus.

Here, when the amount of power that can be supplied by the generator and the amount of power that can be supplied by the fuel cell both exceed the predetermined reference power, the DC distribution system selects which one of the amount of power that can be supplied by the generator and the amount of power that can be supplied by the fuel cell is larger. One controls the supply of power to the load through the DC bus.

In step 340, as a result of comparing the amount of power that can be supplied, the DC distribution system controls the other one of the generator and the fuel cell to charge the battery.

For example, if the amount of power that can be supplied by the generator is greater than the amount of power that can be supplied by the fuel cell, the DC distribution system allows the generator to supply power to the load through the DC bus instead of the battery, and the fuel cell supplies power to the battery, so that the battery Control to charge.

In step 350, when the battery is fully charged, the DC distribution system controls the battery to supply power to the load again through the DC bus. When the battery is fully charged, the DC distribution system cuts off the power supplied to the battery from the generator or fuel cell and controls the battery to supply power to the load through the DC bus.

Although not shown in FIG. 3, the DC distribution system can bypass the output of the generator, fuel cell, and battery if there is a problem with the converters.

110: Generator 120: Fuel cell 130: Battery
141: AC/DC converter 142: first DC/DC converter
143: Second DC/DC converter
150: Control unit 160: DC bus
171, 172: DC/AC converter 181, 182: load

Claims (10)

generator;
fuel cell;
battery;
an AC/DC converter connected to the generator, a first DC/DC converter connected to the fuel cell, and a second DC/DC converter connected to the battery;
a control unit connected to outputs of the AC/DC converter, the first DC/DC converter, and the second DC/DC converter;
a DC bus connected to the outputs of the AC/DC converter, the first DC/DC converter, and the second DC/DC converter, and connected to the control unit;
A DC/AC converter connected to the DC bus;
Includes a load connected to the DC/AC converter,
When the power supplied from the battery is less than a predetermined reference power, the control unit compares the amount of power that can be supplied by the generator and the amount of power that can be supplied by the fuel cell with the predetermined reference power, and compares the amount of power that can be supplied by the generator and the fuel. When the amount of power that can be supplied from the battery exceeds the predetermined reference power, whichever of the amount of power that can be supplied by the generator and the amount of power that can be supplied by the fuel cell supplies power to the load through the DC bus. A DC distribution system characterized by control to supply. According to claim 1,
A DC distribution system, wherein the second DC/DC converter is a bidirectional converter. According to claim 2,
A DC distribution system, wherein the control unit compares the amount of power that can be supplied and then controls the other one of the generator and the fuel cell to charge the battery. According to claim 3,
A DC distribution system, characterized in that when the battery is fully charged, the battery supplies power to the DC bus again. According to claim 1,
A DC distribution system, wherein the control unit is further connected to outputs of the generator, the fuel cell, and the battery. A DC distribution system including a generator, fuel cell, battery, DC bus, and load detecting power supplied from the battery;
When the power supplied from the battery is less than a predetermined reference power, the DC distribution system comparing the amount of power that can be supplied by the generator and the amount of power that can be supplied by the fuel cell with the predetermined reference power; and
As a result of comparing the available power amounts, when the power available from the generator and the power available from the fuel cell exceed the predetermined reference power, the DC distribution system supplies the power available from the generator and the fuel cell. A DC power distribution method comprising controlling one of the available amounts of power to supply power to the load through the DC bus. According to claim 6,
As a result of comparing the amount of power that can be supplied, the DC distribution method further includes controlling the DC distribution system to charge the other one of the generator and the fuel cell to charge the battery. According to claim 7,
When the battery is fully charged, the DC distribution system further includes controlling the battery to supply power to the load through the DC bus again. delete delete