Ship shore power system with segmented direct-current bus and cooperative control method of ship shore power system

Abstract

The ship shore power system comprises a plurality of ship shore electronic systems, and each ship shore electronic system comprises an alternating current bus, a converter, a direct current bus, at least one load, a three-port direct current converter, a power type energy storage system and a control protection device. The alternating-current bus is connected with a converter voltage input end through a first circuit breaker, a converter voltage output end is connected with the direct-current bus through a second circuit breaker, the direct-current bus is connected with a load through a third circuit breaker, the three-port direct-current converter is connected with the direct-current bus through a fourth circuit breaker, and the power type energy storage system is connected with the three-port direct-current converter. The control protection devices of the front and rear ship shore electronic systems are in communication connection, the direct current bus is connected with the direct current bus through the interconnection switch, and the control protection devices of the front and rear ship shore electronic systems are respectively connected with ports of the three-port direct current converter. Through cooperative control of two front and rear ship shore electronic systems, shore power is provided for ships.

Description

Technical Field

[0001] The present invention relates to the field of ship shore power systems, and in particular to a direct current bus segmented ship shore power system and a coordinated control method thereof. Background Art

[0002] When a ship docks at a port, it usually uses ship generator technology to solve the problem of ship electricity consumption to ensure the normal operation of the ship's pump group, ventilation device, lighting device, communication device and other facilities. When a ship docks at a port and uses its ship generator to generate electricity, the ship generator after starting up will produce air pollution and a large noise problem, affecting the normal operation environment of the port.

[0003] In order to solve the air pollution and noise pollution problems caused by the start-up of ship generators, the ship shore power system (referred to as the ship shore power system) came into being. The existing ship shore power system includes three important components: the shore power supply system, the ship-to-shore conversion system and the ship power receiving system. The ship-to-shore conversion system is the core part of the shore power system, and its basic function is to convert the dock power supply into the ship power supply. Among them, the ship-to-shore conversion system includes converters, circuit breakers and control and protection devices. The control and protection device is the guarantee of the stable operation of the ship-to-shore conversion system. The control and protection device realizes the rapid removal of faults and the coordinated cooperation of the system.

[0004] Therefore, how to reduce air pollution and noise while providing normal power supply to ships after docking to maintain the normal operation of their facilities has become a technical problem that needs to be solved in the field of ship power supply. Summary of the invention

[0005] The first technical problem to be solved by the present invention is to provide a ship shore power system with a DC bus segmentation in view of the above-mentioned prior art.

[0006] The second technical problem to be solved by the present invention is to provide a ship shore power coordinated control method applied to the above-mentioned ship shore power system in view of the above-mentioned prior art.

[0007] The technical solution adopted by the present invention to solve the first technical problem is: a DC bus segmented ship shore power system, characterized by having multiple ship shore electronic systems; wherein the ship shore electronic system includes:

[0008] AC busbar;

[0009] A converter, whose voltage input terminal is connected to the AC bus through a first circuit breaker;

[0010] A DC bus, connected to a voltage output terminal of the converter via a second circuit breaker;

[0011] at least one load connected to the DC bus via a third circuit breaker;

[0012] A three-port DC converter connected to the DC bus through a fourth circuit breaker, the three-port DC converter having a first port, a second port and a third port;

[0013] A power type energy storage system connected to a three-port DC converter;

[0014] A control protection device is respectively connected to the first circuit breaker, the converter, the DC bus, the three-port DC converter and the power type energy storage system;

[0015] Among them, in the two adjacent ship-shore electronic systems, the control and protection device of the front ship-shore electronic system is communicatively connected with the control and protection device of the rear ship-shore electronic system, the DC bus of the front ship-shore electronic system is connected to the DC bus of the rear ship-shore electronic system through a connecting switch, the control and protection device of the front ship-shore electronic system is connected to the first port of the three-port DC converter, and the control and protection device of the rear ship-shore electronic system is connected to the second port of the three-port DC converter.

[0016] Improved, in the DC bus segmented ship shore power system, the control and protection device of the previous ship shore electronic system is connected to the control and protection device of the next ship shore electronic system via optical fiber communication.

[0017] Further improved, in the ship shore power system with DC bus segmentation, the control and protection device includes:

[0018] A data acquisition module, which acquires real-time operating parameters of the converter corresponding to the control protection device; wherein the real-time operating parameters include at least one of voltage, current and temperature;

[0019] A state judgment module is connected to the data acquisition module, and generates a tripping instruction for controlling the first circuit breaker and the second circuit breaker based on processing the real-time working parameters of the converter acquired by the data acquisition module;

[0020] A protection module, connected to the state judgment module, the three-port DC converter and the power-type energy storage system, respectively, drives the first circuit breaker and the second circuit breaker to execute the tripping instruction of the state judgment module; and sends the tripping instruction to the three-port DC converter and the power-type energy storage system respectively;

[0021] The collaborative control module is respectively connected to the protection module, the three-port DC converter and the power energy storage system, receives the tripping command forwarded by the protection module, and controls the shutdown of the converter corresponding to the control protection device;

[0022] The collaborative control module sends a tripping command to a collaborative control module of another control protection device to start collaborative control.

[0023] Furthermore, in the DC bus segmented ship shore power system, the protection module triggers the first circuit breaker and the second circuit breaker to execute the tripping instruction of the state judgment module through the fast DO drive board.

[0024] The technical solution adopted by the present invention to solve the second technical problem is: a ship shore power coordinated control method applied to any of the ship shore power systems, characterized in that it comprises the following steps:

[0025] Step 1: The first control and protection device collects real-time operating parameters of the converter corresponding to the first control and protection device; wherein the real-time operating parameters of the converter include at least one of voltage, current and temperature;

[0026] Step 2: The first control protection device determines the state of the converter according to the collected real-time working parameters of the converter:

[0027] When the converter fails, a tripping instruction is generated to instruct the first circuit breaker and the second circuit breaker to trip, and the process goes to step 3; otherwise, the process goes to step 1;

[0028] Step 3, the first control protection device controls the first circuit breaker and the second circuit breaker to execute the tripping instruction respectively, and controls the converter with the fault to stop running;

[0029] Step 4, the first control protection device sends a trip command to the three-port DC converter and the power type energy storage system respectively;

[0030] Step 5, the three-port DC converter and the power type energy storage system cooperate to maintain the DC voltage stability of the DC bus corresponding to the first control and protection device;

[0031] Step 6: The first control and protection device sends the trip command generated by it to the second control and protection device coordinated therewith to start the coordinated control mechanism;

[0032] Step 7: The second control and protection device determines whether the tie switch meets the closing condition:

[0033] When the tie switch meets the closing condition, a pre-closing instruction for the tie switch is generated, and the process goes to step 8; otherwise, information that the tie switch does not meet the closing condition is sent to the three-port DC converter, and the process goes to step 13;

[0034] Step 8: The first control and protection device determines that the second circuit breaker corresponding to it is in an open state, and sends the open state of the second circuit breaker to the second control and protection device;

[0035] Step 9, the second control protection device controls the tie switch to perform a closing action through the pre-closing instruction generated by it;

[0036] Step 10: The second control and protection device makes a judgment based on the success or failure of the tie switch closing:

[0037] When the tie switch is closed, go to step 11; otherwise, go to step 12;

[0038] Step 11, making the first port of the three-port DC converter exit the DC voltage control mode and making the first port switch to the power control mode, and making the power type energy storage system maintain the SOC stable output, and then proceeding to step 13;

[0039] Step 12, the three-port DC converter system adjusts the power mode provided by the third port to the power mode provided by the second port and maintains the power output of the first port, and allows the power type energy storage system to maintain a stable SOC output through the third port, and then proceeds to step 13;

[0040] Step 13: The second control and protection device controls the corresponding converter to operate so as to maintain the operation of the DC bus corresponding to the second control and protection device.

[0041] Furthermore, in the ship shore power coordinated control method, the first control and protection device determines the state of the converter in the following manner:

[0042] When the real-time operating parameter of the converter exceeds a preset operating parameter threshold and is maintained for a preset time period, it is determined that the converter has failed; otherwise, it is determined that the converter has not failed.

[0043] Improved, in the ship shore power coordinated control method, in step 5, when the three-port DC converter and the power type energy storage system cooperate to maintain the DC voltage stability of the DC bus corresponding to the first control protection device, the power type energy storage system is preferentially discharged to maintain the DC voltage stability of the DC bus.

[0044] Furthermore, in the ship shore power coordinated control method, when the power-type energy storage system detects that its state of charge SOC value is close to a preset state of charge SOC value, the power-type energy storage system automatically modifies its preset state of charge SOC value to maintain the power supply support of the power-type energy storage system to the DC bus.

[0045] Improved, in the ship shore power coordinated control method, in step 8, when the first control and protection device determines that the second circuit breaker corresponding to it is not in an open state, the first control and protection device again orders the second circuit breaker to perform a tripping action.

[0046] Furthermore, in the ship-shore power coordinated control method, when the first control and protection device determines that the second circuit breaker is still in a closed state, the first control and protection device sends a prompt message of power failure to the ship connected to the DC bus corresponding to the first control and protection device to the shore power monitoring system.

[0047] Compared with the prior art, the advantages of the present invention are as follows: the ship shore power system of the present invention is provided with at least two ship shore electronic systems, and each ship shore electronic system is provided with an AC bus, a DC bus, a three-port DC converter, a power type energy storage system and a control protection device, the control protection device is respectively connected to each component, the DC bus in each ship shore electronic system is independent of each other (that is, the two DC buses are segmented), and each independent DC bus is connected to the power type energy storage system through a three-port DC converter, so that when a control protection device determines that its DC bus cannot provide shore power for the ship, the control protection device sends coordination information to another control protection device, thereby completing coordinated control, ensuring that the DC bus in the ship shore electronic system where the control protection device is located provides shore power for the ship, and avoiding air pollution and noise pollution caused by the shore power system supplying power to the ship. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 The figure is a schematic diagram of a ship shore power system with a segmented DC bus in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The present invention is further described in detail below with reference to the accompanying drawings.

[0050] This embodiment provides a ship shore power system with a DC bus segment. Figure 1 As shown, the DC bus segmented ship shore power system of this embodiment has multiple ship shore electronic systems S; wherein each ship shore electronic system S includes:

[0051] AC bus L1;

[0052] Converter 1, whose voltage input terminal is connected to AC bus L1 through a first circuit breaker Q1;

[0053] The DC bus L2 is connected to the voltage output terminal of the converter 1 through the second circuit breaker Q2;

[0054] At least one load 2 is connected to the DC bus L2 via a third circuit breaker Q3;

[0055] A three-port DC converter 3 is connected to the DC bus L2 via a fourth circuit breaker Q4, and the three-port DC converter 3 has a first port 31, a second port 32 and a third port 33;

[0056] A power type energy storage system 4 connected to the three-port DC converter 3;

[0057] The control protection device 5 is respectively connected to the first circuit breaker Q1, the converter 1, the DC bus L2, the three-port DC converter 3 and the power type energy storage system 4;

[0058] Among them, in the two adjacent ship shore electronic systems, the control and protection device of the previous ship shore electronic system is communicatively connected with the control and protection device of the subsequent ship shore electronic system. For example, here it is connected through fiber communication. The DC bus of the previous ship shore electronic system is connected to the DC bus of the subsequent ship shore electronic system through the connecting switch Q5. The control and protection device of the previous ship shore electronic system is connected to the first port 31 of the three-port DC converter 3, and the control and protection device of the subsequent ship shore electronic system is connected to the second port 32 of the three-port DC converter 3.

[0059] More specifically, the control and protection device 5 of this embodiment includes:

[0060] A data acquisition module, which acquires real-time operating parameters of the converter corresponding to the control protection device; wherein the real-time operating parameters include at least one of voltage, current and temperature;

[0061] A state judgment module is connected to the data acquisition module, and generates a tripping instruction for controlling the first circuit breaker and the second circuit breaker based on processing the real-time working parameters of the converter acquired by the data acquisition module;

[0062] A protection module, connected to the state judgment module, the three-port DC converter and the power-type energy storage system, respectively, drives the first circuit breaker and the second circuit breaker to execute the tripping instruction of the state judgment module; and sends the tripping instruction to the three-port DC converter and the power-type energy storage system respectively;

[0063] The collaborative control module is respectively connected to the protection module, the three-port DC converter and the power energy storage system, receives the tripping command forwarded by the protection module, and controls the shutdown of the converter corresponding to the control protection device;

[0064] The cooperative control module sends a tripping instruction to another cooperative control module of a control protection device to start cooperative control. The protection module triggers the first circuit breaker and the second circuit breaker to execute the tripping instruction of the state judgment module through a fast DO driving board.

[0065] This embodiment also provides a ship shore power coordinated control method applied to the above ship shore power system. Specifically, the ship shore power coordinated control method of this embodiment includes the following steps 1 to 13:

[0066] Step 1: The first control and protection device collects real-time operating parameters of the converter corresponding to the first control and protection device; wherein the real-time operating parameters of the converter include at least one of voltage, current and temperature;

[0067] Step 2: The first control protection device determines the state of the converter according to the collected real-time working parameters of the converter:

[0068] When the converter fails, a tripping instruction is generated to instruct the first circuit breaker and the second circuit breaker to trip, and the process goes to step 3; otherwise, the process goes to step 1;

[0069] Step 3, the first control protection device controls the first circuit breaker and the second circuit breaker to execute the tripping instruction respectively, and controls the converter with the fault to stop running;

[0070] Step 4, the first control protection device sends a trip command to the three-port DC converter and the power type energy storage system respectively;

[0071] Step 5, the three-port DC converter and the power type energy storage system cooperate to maintain the DC voltage stability of the DC bus corresponding to the first control and protection device;

[0072] Step 6: The first control and protection device sends the trip command generated by it to the second control and protection device coordinated therewith to start the coordinated control mechanism;

[0073] Step 7: The second control and protection device determines whether the tie switch meets the closing condition:

[0074] When the tie switch meets the closing condition, a pre-closing instruction for the tie switch is generated, and the process goes to step 8; otherwise, information that the tie switch does not meet the closing condition is sent to the three-port DC converter, and the process goes to step 13;

[0075] Step 8: The first control and protection device determines that the second circuit breaker corresponding to it is in an open state, and sends the open state of the second circuit breaker to the second control and protection device;

[0076] Step 9, the second control protection device controls the tie switch to perform a closing action through the pre-closing instruction generated by it;

[0077] Step 10: The second control and protection device makes a judgment based on the success or failure of the tie switch closing:

[0078] When the tie switch is closed, go to step 11; otherwise, go to step 12;

[0079] Step 11, making the first port of the three-port DC converter exit the DC voltage control mode and making the first port switch to the power control mode, and making the power type energy storage system maintain the SOC stable output, and then proceeding to step 13;

[0080] Step 12, the three-port DC converter system adjusts the power mode provided by the third port to the power mode provided by the second port and maintains the power output of the first port, and allows the power type energy storage system to maintain a stable SOC output through the third port, and then proceeds to step 13;

[0081] Step 13: The second control and protection device controls the corresponding converter to operate so as to maintain the operation of the DC bus corresponding to the second control and protection device.

[0082] Specifically, in the ship-shore power coordinated control method of this embodiment, the first control and protection device judges the status of the converter as follows: when the real-time operating parameter of the converter exceeds the preset operating parameter threshold and maintains the preset time, it is determined that the converter has failed; otherwise, it is determined that the converter has not failed.

[0083] In addition, in the above step 5, when the three-port DC converter and the power type energy storage system cooperate to maintain the DC voltage stability of the DC bus corresponding to the first control protection device, the power type energy storage system is preferentially discharged to maintain the DC voltage stability of the DC bus.

[0084] Of course, when the power type energy storage system of this embodiment detects that its state of charge SOC value is close to the state of charge SOC preset value, the power type energy storage system automatically modifies its state of charge SOC preset value to maintain the power supply support of the power type energy storage system to the DC bus. For example, the state of charge SOC preset value here is 20%, and the automatically modified state of charge SOC preset value is 10%.

[0085] It should be noted that, in step 8, when the first control and protection device determines that the second circuit breaker corresponding to it is not in the open state, the first control and protection device again trips the second circuit breaker. Of course, once the first control and protection device determines that the second circuit breaker is still in the closed state, the first control and protection device sends a prompt message of power failure of the ship connected to the DC bus corresponding to the first control and protection device to the shore power monitoring system.

[0086] Although the preferred embodiments of the present invention are described in detail above, it should be clearly understood that various modifications and variations are possible for those skilled in the art. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. The DC bus segmented ship shore power system is characterized by: There are multiple ship-shore electronic systems (S); wherein the ship-shore electronic system includes: AC busbar (L1); A converter (1), whose voltage input terminal is connected to an AC bus (L1) via a first circuit breaker (Q1); A DC bus (L2) connected to a voltage output terminal of the converter (1) via a second circuit breaker (Q2); at least one load (2) connected to the DC bus (L2) via a third circuit breaker (Q3); A three-port DC converter (3) connected to the DC bus (L2) via a fourth circuit breaker (Q4), the three-port DC converter (3) having a first port (31), a second port (32) and a third port (33); A power type energy storage system (4) connected to the three-port DC converter (3); A control protection device (5) is respectively connected to the first circuit breaker (Q1), the converter (1), the DC bus (L2), the three-port DC converter (3) and the power type energy storage system (4); Among them, in two adjacent ship shore electronic systems, the control protection device of the front ship shore electronic system is communicatively connected with the control protection device of the rear ship shore electronic system, the DC bus of the front ship shore electronic system is connected to the DC bus of the rear ship shore electronic system through a connecting switch (Q5), the control protection device of the front ship shore electronic system is connected to the first port (31) of the three-port DC converter (3), and the control protection device of the rear ship shore electronic system is connected to the second port (32) of the three-port DC converter (3).

2. The DC bus segmented ship shore power system according to claim 1, characterized in that: The control and protection device of the first ship shore electronic system is connected to the control and protection device of the second ship shore electronic system via optical fiber communication.

3. The DC bus segmented ship shore power system according to claim 1, characterized in that: The control and protection device comprises: A data acquisition module, which acquires real-time operating parameters of the converter corresponding to the control protection device; wherein the real-time operating parameters include at least one of voltage, current and temperature; A state judgment module is connected to the data acquisition module, and generates a tripping instruction for controlling the first circuit breaker and the second circuit breaker based on processing the real-time working parameters of the converter acquired by the data acquisition module; A protection module, connected to the state judgment module, the three-port DC converter and the power type energy storage system, respectively, drives the first circuit breaker and the second circuit breaker to execute the tripping instruction of the state judgment module; and sends the tripping instruction to the three-port DC converter and the power type energy storage system respectively; The collaborative control module is connected to the protection module, the three-port DC converter and the power energy storage system respectively, receives the tripping command forwarded by the protection module, and controls the shutdown of the converter corresponding to the control protection device; The collaborative control module sends a tripping command to a collaborative control module of another control protection device to start collaborative control.

4. The DC bus segmented ship shore power system according to claim 3, characterized in that: The protection module triggers the first circuit breaker and the second circuit breaker to execute the tripping instruction of the state judgment module through the fast DO driving board.

5. The ship shore power coordinated control method applied to the ship shore power system according to any one of claims 1 to 4, characterized in that: The steps include: Step 1: The first control and protection device collects real-time operating parameters of the converter corresponding to the first control and protection device; wherein the real-time operating parameters of the converter include at least one of voltage, current and temperature; Step 2: The first control protection device determines the state of the converter according to the collected real-time working parameters of the converter: When the converter fails, a tripping instruction is generated to instruct the first circuit breaker and the second circuit breaker to trip, and the process goes to step 3; otherwise, the process goes to step 1; Step 3, the first control protection device controls the first circuit breaker and the second circuit breaker to execute the tripping instruction respectively, and controls the converter with the fault to stop running; Step 4, the first control protection device sends a trip command to the three-port DC converter and the power type energy storage system respectively; Step 5, the three-port DC converter and the power type energy storage system cooperate to maintain the DC voltage stability of the DC bus corresponding to the first control and protection device; Step 6: The first control and protection device sends the trip command generated by it to the second control and protection device cooperating with it to start the coordinated control mechanism; Step 7: The second control and protection device determines whether the tie switch meets the closing condition: When the tie switch meets the closing condition, a pre-closing instruction for the tie switch is generated, and the process goes to step 8; otherwise, information that the tie switch does not meet the closing condition is sent to the three-port DC converter, and the process goes to step 13; Step 8: The first control and protection device determines that the second circuit breaker corresponding to it is in an open state, and sends the open state of the second circuit breaker to the second control and protection device; Step 9, the second control protection device controls the tie switch to perform a closing action through the pre-closing instruction generated by it; Step 10: The second control and protection device makes a judgment based on the success or failure of the tie switch closing: When the tie switch is closed, go to step 11; otherwise, go to step 12; Step 11, making the first port of the three-port DC converter exit the DC voltage control mode and making the first port switch to the power control mode, and making the power type energy storage system maintain the SOC stable output, and then proceeding to step 13; Step 12, the three-port DC converter system adjusts the power mode provided by the third port to the power mode provided by the second port and maintains the power output of the first port, and allows the power type energy storage system to maintain a stable SOC output through the third port, and then proceeds to step 13; Step 13: The second control and protection device controls the corresponding converter to operate so as to maintain the operation of the DC bus corresponding to the second control and protection device.

6. The ship shore power coordinated control method according to claim 5, characterized in that: The first control and protection device determines the status of the converter in the following manner: When the real-time operating parameter of the converter exceeds a preset operating parameter threshold and is maintained for a preset time period, it is determined that the converter has failed; otherwise, it is determined that the converter has not failed.

7. The ship shore power coordinated control method according to claim 5, characterized in that: In step 5, when the three-port DC converter and the power type energy storage system cooperate to maintain the DC voltage stability of the DC bus corresponding to the first control protection device, the power type energy storage system is preferentially discharged to maintain the DC voltage stability of the DC bus.

8. The ship shore power coordinated control method according to claim 7, characterized in that: Also includes: When the power-type energy storage system detects that its state of charge SOC value is close to a preset state of charge SOC value, the power-type energy storage system automatically modifies its preset state of charge SOC value to maintain the power supply support of the power-type energy storage system to the DC bus.

9. The ship shore power coordinated control method according to claim 5, characterized in that: In step 8, when the first control and protection device determines that the corresponding second circuit breaker is not in the open state, the first control and protection device again instructs the second circuit breaker to perform a tripping action.

10. The ship shore power coordinated control method according to claim 9, characterized in that: Also includes: When the first control and protection device determines that the second circuit breaker is still in the closed state, the first control and protection device sends a prompt message of power failure to the ship connected to the DC bus corresponding to the first control and protection device to the shore power monitoring system.

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