Micro-grid-containing double-power-station ship integrated power system

Abstract

A front main power station and a rear main power station are arranged on a ship, the front main power station and the rear main power station are each provided with a medium-voltage main distribution board, the rated voltage of the medium-voltage main distribution boards is AC6.6 kV, and the medium-voltage main distribution boards are used for supplying power to an electric propulsion device, a side thrust motor and a lower-level auxiliary power grid; the auxiliary power grid comprises two voltage levels of AC400V and AC230V, and the medium-voltage main distribution board is subjected to voltage reduction through an AC6.6 kV / AC400V transformer to supply power; the micro-grid comprises an AC400V and AC230V two-stage power distribution system, and is provided with a micro-grid power distribution board, a point of common connection (PCC), a wind power generation device, a photovoltaic power generation device, a bidirectional energy storage system and an AC400V / AC230V transformer; the micro-grid and the auxiliary power grid operate in a grid-connected mode under the normal working condition, and operation mode switching is achieved when the main power station or the micro-grid breaks down. The invention provides a micro-grid-containing double-power-station ship integrated power system architecture and an operation mode thereof, and coordinated operation of a double-power-station integrated power system and a micro-grid is realized.

Description

Technical Field

[0001] This invention relates to the field of marine power system technology, and in particular to a dual-power station integrated marine power system with microgrid. Background Technology

[0002] Large cruise ships, as a symbol of international high-end shipbuilding capabilities, can strongly drive tourism consumption and the coordinated development of the industrial chain, possessing significant industrial and economic value. In recent years, with the significant improvement of my country's comprehensive national strength and shipbuilding technology, my country has also built large ocean-going luxury cruise ships, filling gaps in related industries; more and more technologically advanced large cruise ships will be built in the future. Large ocean-going luxury cruise ships generate huge amounts of fuel consumption and greenhouse gas emissions daily during operation. Adopting new technologies to reduce the consumption of fossil fuels on ships would be of significant importance to the technological development of my country's cruise industry. On the other hand, to improve comfort and survivability, future large ocean-going luxury cruise ships tend to adopt integrated power systems with multiple power stations. Summary of the Invention

[0003] To address the application of marine renewable energy power generation technology in the integrated power system of large ocean-going luxury cruise ships, a dual-power station ship integrated power system with microgrid is proposed. This system fully leverages the advantages of large-scale installation of marine renewable energy power generation devices on large cruise ship platforms, and achieves coordinated operation of the dual-power station integrated power system and the microgrid.

[0004] The technical solution of this invention is: a dual-power station integrated ship power system with microgrid, comprising: The forward and aft main power stations are installed on the ship, and the forward and aft main power stations are equipped with the same number and type of main diesel generator sets, respectively. The front and rear main power stations are each equipped with a medium-voltage main switchboard with a rated voltage of AC6.6kV, which is used to supply power to the electric propulsion device, the side thrust motor and the downstream auxiliary power grid. The AC6.6kV busbars of the front and rear main distribution boards are connected by jumper wires; The auxiliary power grid includes two voltage levels: AC400V and AC230V. It is supplied by the medium-voltage main distribution board after being stepped down by an AC6.6kV / AC400V transformer. The AC400V busbars of the front and rear main distribution boards are also connected by jumper wires. The microgrid contains two-level power distribution systems: AC400V and AC230V. It is equipped with a microgrid distribution board, a point of common coupling (PCC), wind power generation devices, photovoltaic power generation devices, a two-way energy storage system, and AC400V / AC230V transformers. The microgrid is connected to the AC400V busbar of the emergency distribution board through the common connection point PCC, and is connected to the AC230V busbar of the front main distribution board through a jumper wire as a backup power supply branch. The microgrid operates in parallel with the auxiliary power grid under normal operating conditions, and switches to a different operating mode when the main power station or the microgrid fails.

[0005] Preferably, the wind power generation device is a rotary wind turbine, and the photovoltaic power generation device uses flexible thin-film photovoltaic modules, which are installed on the outer wall of the hull or below the passenger cabin balcony.

[0006] Preferably, the bidirectional energy storage system includes a lithium iron phosphate battery pack with a rated voltage of DC560V and a matching bidirectional fast converter, used to smooth microgrid power fluctuations and maintain dynamic stability of AC400V bus voltage.

[0007] Preferably, the AC400V busbar of the microgrid distribution board is divided into three sections by a disconnecting switch, which are respectively used to connect to the wind power generation device, the load and energy storage system, and the photovoltaic power generation device.

[0008] Preferably, the auxiliary power grid side of the main power station is also equipped with a parking and emergency diesel generator set. This unit starts when the main power station fails to supply power and operates in parallel with the microgrid through the emergency distribution board and PCC.

[0009] Preferably, the system executes different operating strategies according to the ship's operating conditions, including: port entry and exit, night navigation, cruise and entertainment, maximum navigation, night anchoring, dock berthing, and emergency conditions; under different operating conditions, the number of main generator sets started and stopped, the operating status of wind and solar power generation devices, the microgrid's grid connection / off-grid status, and the energy storage system's operating mode are adjusted accordingly.

[0010] Preferably, the system is powered by shore power when the system is berthed at the dock; in the emergency situation of microgrid power failure, the PCC is immediately disconnected, the wind and solar power generation and energy storage system are stopped, and the power supply to the main power station or the front main distribution board is switched to AC230V for important loads.

[0011] Preferably, the AC6.6kV / AC400V daily service transformer serves as a backup for each other between the front and rear substations, and achieves open-loop operation through circuit breaker interlocking logic.

[0012] The beneficial effects of this invention are as follows: This invention, a dual-power station integrated ship power system incorporating a microgrid, aims to improve the economic and social benefits of dual-power station integrated power systems on large cruise ship platforms. Based on the characteristics of microgrids, it proposes an architecture and operation mode for a dual-power station integrated ship power system incorporating a microgrid. This fully leverages the advantages of large-scale deployment of marine renewable energy power generation devices on large cruise ship platforms, achieving coordinated operation between the dual-power station integrated power system and the microgrid. It provides an application approach to promote the widespread application of green power technologies on large cruise ship platforms. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of an embodiment of the integrated ship power system with microgrids for dual power stations according to the present invention. Detailed Implementation

[0014] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0015] This invention addresses the application needs of new energy technologies in the power systems of large cruise ships by providing a dual-power station integrated ship power system with a microgrid. The ship's power system comprises three voltage levels: AC6.6kV, AC400V, and AC230V. The AC6.6kV is the rated voltage of the medium-voltage power grid; the auxiliary power grid includes both AC400V and AC230V rated voltages; and a microgrid is incorporated, internally containing both AC400V and AC230V rated voltages. The AC6.6kV power grid supplies power to the electric propulsion unit, the side thrusters, and the downstream AC400V auxiliary power grid. The auxiliary power grid primarily supplies power to the ship's auxiliary power equipment, control cabinets, charging and discharging panels, and other loads. The microgrid's AC400V distribution system, while absorbing power fluctuations from wind and solar power generation, primarily supplies power to most of the critical AC230V loads.

[0016] The aforementioned integrated power system with a microgrid and two substations consists of a front and a rear main substation. Both the front and rear main substations are equipped with the same number and type of main generator sets. An emergency / shutdown diesel generator set is installed on the auxiliary power grid side of the rear substation. The main generator sets of the front (rear) substation are connected to the corresponding front (rear) medium-voltage main switchboard via main circuit breakers; the 6.6kV busbars of the front and rear main switchboards are connected using jumper wires.

[0017] The front (rear) main distribution board is connected to the AC6.6kV / AC400V transformer and the front (rear) 400V distribution panel busbar in the auxiliary power grid via a circuit breaker. The 400V busbar of the front main distribution board is connected to the 400V busbar of the rear main distribution board via jumper wires.

[0018] The 400V busbar of the emergency distribution board is connected to the AC400V busbar of the microgrid distribution board through the common connection point PCC; the 230V busbar of the main distribution board is connected to the AC230V busbar of the microgrid distribution board through a jumper wire, serving as its backup power supply branch.

[0019] The aforementioned integrated power system with a microgrid includes a microgrid distribution board, a common connection point (PCC) device, several wind power generation devices, several photovoltaic power generation device components, a bidirectional energy storage system, an AC400V / AC230V transformer, and a microgrid power monitoring facility, etc.

[0020] The microgrid distribution board includes a 400V AC distribution panel and a 230V AC distribution panel. The microgrid busbar is divided into three sections by a disconnecting switch, allowing for flexible operation of wind power and photovoltaic (PV) power generation units, which can be selectively connected in parallel or disconnected from the busbar as needed. The point of common coupling (PCC) is located on the microgrid distribution board side and mainly consists of a grid-connected converter and protection devices. The bidirectional energy storage system primarily includes a DC 560V lithium iron phosphate battery bank and a matching bidirectional fast converter. The battery bank maintains the dynamic stability of the microgrid's AC 400V busbar voltage through the rapid charging and discharging of the bidirectional converter. The wind power generation unit uses a rotary wind turbine, and the PV power generation unit uses flexible photovoltaic modules.

[0021] The aforementioned integrated power system with dual power stations and microgrids, taking a large cruise ship as a reference, executes different operating strategies under port entry / exit conditions, nighttime navigation conditions, cruise and entertainment conditions, maximum navigation conditions, nighttime anchoring conditions, dock berthing conditions, and emergency conditions.

[0022] During port entry and exit operations, the main power station operates two main generator sets. This can be done with one generator set operating at each of the upstream and downstream power stations, or with both generator sets operating within a single power station. The microgrid operates in parallel with the auxiliary power grid via a common connection point device. Wind power and photovoltaic installations operate normally, and the microgrid energy storage unit operates normally. During nighttime navigation, the main power station operates 3 main generators, and 1 front (rear) power station and 2 rear (front) power stations can be operated. The microgrid is connected to the auxiliary power grid through the common connection point equipment. The wind power unit is running normally, the photovoltaic unit is in standby mode, and the microgrid energy storage unit is operating normally. In cruise entertainment mode, all four main generators of the front and rear power stations need to be turned on. The microgrid is connected to the auxiliary power grid through the common connection point equipment. The wind power unit and photovoltaic unit are operating normally, and the microgrid energy storage unit is operating normally. Under maximum operating conditions, all four main generators of the front and rear power stations need to be turned on. The microgrid is connected to the auxiliary power grid through the common connection point equipment. The wind power unit and photovoltaic unit are operating normally, and the microgrid energy storage unit is operating normally. During nighttime mooring operations, one unit each from the front and rear power stations can be operated; or two units from the front (or rear) power stations. Wind power units are operating normally, photovoltaic units are in standby mode, and the microgrid energy storage unit is operating normally. When the pier is berthed, it is powered by shore power equipment. In the emergency situation of power failure of the main power station, all main diesel generator units are shut down and the standby emergency generator units are started. At this time, the standby emergency generator units continue to operate in parallel with the microgrid through the emergency switchboard and PCC.

[0023] In emergency situations where microgrid power supply fails, the PCC should be immediately disconnected, wind and solar power generation units should cease operation, bidirectional energy storage devices should cease operation, and power supply branches should be switched. The main power station's status generally remains unchanged.

[0024] Example 1 like Figure 1 As shown, Embodiment 1 of the present invention, guided by the overall design requirements of the power system of a large ocean-going luxury cruise ship, discloses a dual-power station integrated ship power system including a microgrid. In this embodiment, the capacity of the power supply equipment is further specified based on the power load calculation and installed equipment of the large ocean-going luxury cruise ship.

[0025] In this embodiment, the top-level architecture adopts a power grid architecture of "dual main power stations at the front and rear + microgrid coordination". Among them, the dual main power stations at the front and rear are the core power supply areas of this embodiment. They are flexibly coordinated with the microgrid through independent power supply in physical partitions to meet the high power supply reliability, energy saving of marine new energy power generation, and multi-condition power supply requirements of large cruise ship platforms.

[0026] For ease of description, the main loads in this embodiment are two propulsion systems, each with a rated power of 17.2MW; and two side thrusters, each with a rated power of 2MW. The rated power of the ship's air conditioning load is approximately 10MW. The rated power of other auxiliary electromechanical equipment and some living and entertainment facilities (AC380V) is approximately 9.1MW, plus approximately 800kW of AC380V emergency load; the rated power of the AC220V loads for guest room appliances and some conventional lighting on large cruise ships is approximately 9.4MW, plus approximately 90kW of AC220V emergency load.

[0027] In this embodiment, the rear power station and its power supply area are equipped with two medium-voltage main diesel generator sets, G1 and G2, each with a rated power of 16.8MW; one rear main switchboard (BMSB), which includes the relevant functional panels for the AC6.6kV busbar section and the AC400V busbar section; one AC6.6kV / AC400V daytime transformer; one side-push device (one side-push motor + one side-push frequency converter); and one main electric propulsion system (one propulsion transformer + one propulsion frequency converter + one propulsion motor), with a propulsion power of 17.2MW. Among them, generator set G1 is connected to the AC6.6kV busbar of the rear main switchboard through frame circuit breaker ACB1, generator set G2 is connected to the AC6.6kV busbar of the rear main switchboard through circuit breaker ACB2; side push device 1 is connected to the AC6.6kV busbar of the rear main switchboard through circuit breaker ACB6; push transformer T2 is connected to the AC6.6kV busbar of the rear main switchboard through ACB7; the AC6.6kV busbar of the rear main switchboard is connected to the ACB6 of the front main power station through circuit breaker ACB8 and ACB9. The AC 6.6kV busbar is connected; the AC 6.6kV busbar of the rear main distribution board is connected to the incoming terminal of the AC 6.6kV / AC 400V day-use transformer T1 via circuit breaker ACB5. The outgoing terminal of transformer T1 is then connected to the AC 400V busbar of the rear main distribution board via circuit breaker ACB14. The AC 400V busbar of the rear main distribution board mainly distributes power to the AC 400V loads in the vicinity of the rear area. The AC 400V busbar is connected to the AC 400V busbar of the front power station main distribution board via circuit breakers ACB15 and ACB16. An additional 6MW emergency generator unit TG is installed in the power supply area of ​​the rear power station. TG is connected to the AC 400V busbar of the emergency distribution board via circuit breaker ACB13.

[0028] Similarly, in this embodiment, the front power station and its power supply area are equipped with two medium-voltage main diesel generator sets, G3 and G4, each with a rated power of 16.8MW; one front switchboard (FMSB). The FMSB includes the relevant functional panels for the AC6.6kV busbar section and the AC400V busbar section; one AC6.6kV / AC400V daytime transformer; one side-push device (one side-push motor + one side-push frequency converter); and one main electric propulsion device (one propulsion transformer + one propulsion frequency converter + one propulsion motor). Among them, generator set G3 is connected to the AC6.6kV busbar of the front main switchboard via frame circuit breaker ACB3, and generator set G4 is connected to the AC6.6kV busbar of the front main switchboard via circuit breaker ACB4; the bow thruster 2 is connected to the AC6.6kV busbar of the front main switchboard via circuit breaker ACB11; the propulsion transformer T3 is connected to the AC6.6kV busbar of the front main switchboard via ACB10; the AC6.6kV busbar of the front main switchboard is connected to the incoming terminal of the AC6.6kV / AC390V day transformer T4 via circuit breaker ACB12, and the outgoing terminal of transformer T4 is then connected to the AC400V busbar of the rear main switchboard via circuit breaker ACB17; the AC400V busbar of the front main switchboard mainly distributes AC400V loads in the vicinity of the front area.

[0029] In this embodiment, the day-use transformers T1 and T4 form a mutual backup, and their related circuit breakers (ACB5 and ACB14 are interlocked with logic, and ACB14 and ACB17 are interlocked with logic) are also interlocked. Under normal circumstances, T1 is in operation, T4 is disconnected, and the power grid operates in an open-loop manner.

[0030] In this embodiment, a microgrid adapted to the large cruise ship platform is constructed, which can be harmoniously integrated into the dual-power station integrated power system network architecture. First, a suitability demonstration of the offshore renewable energy power generation equipment and the platform is required. The basic principle is that the installation of the offshore renewable energy power generation equipment should not affect the normal navigation of the ship and the safe operation of the power system. In this embodiment, the microgrid power supply area includes the following main components: a point of common coupling (PCC) device, a complete set of wind turbine components (wind turbine generator set + wind power grid-connected inverter), photovoltaic power generation equipment components (photovoltaic cell modules + grid-connected inverter), a microgrid distribution board (GMSB), a microgrid energy storage device (including a DC560V battery bank and a bidirectional converter), and a daily transformer (T7) of AC400V / AC230V.

[0031] Two 125kW rotary wind turbine generators were installed in suitable locations at the rear of the large ocean-going luxury cruise ship platform. Large cruise ship hulls have many curved and irregular surfaces. Considering that the top of a large cruise ship is the main outdoor leisure and entertainment area for passengers, this embodiment uses flexible thin-film solar photovoltaic panels, primarily for installation in suitable centralized locations such as below the balconies of passenger cabins on both sides of the hull and other outer walls. The installed capacity of the thin-film solar photovoltaic panels in this embodiment is approximately 950kW.

[0032] In this embodiment, the microgrid is a grid-connected microgrid. The main function of the configured microgrid energy storage system is to smooth out power fluctuations and support the stability of energy supply and demand in the microgrid. The energy storage system adopts a series architecture of "battery pack + bidirectional converter". Considering the requirements of cycle life and discharge rate, the battery should be a lithium iron phosphate battery (meeting the requirements of the classification society). The battery pack capacity is proposed according to "maximum instantaneous power fluctuation * response time". To meet the requirements of more extreme cases, the battery capacity of the bidirectional energy storage system is estimated. If the photovoltaic device drops by 50% within 10 minutes at 80% rated power; or the wind power device drops from maximum wind speed to 0, then the battery needs to release 250×(10 / 60) + 950×0.8×0.5×(10 / 60) ≈ 41.67 + 63.33 = 105kW within 10 minutes. Considering a certain margin, this embodiment configures a microgrid battery pack with a capacity of 120kWh, approximately 220Ah of battery capacity. The bidirectional converter matched with the battery has a rated power of not less than 130kW and can control the charging power and discharging power of the battery pack according to the preset working mode.

[0033] The AC400V busbar of the microgrid distribution board is divided into three sections by disconnecting switches ISW3 and ISW4. The first section is the connection point for wind power installations; the second section is the connection point for loads, energy storage, and downstream transformers; and the third section is the connection point for photovoltaic installations. This division facilitates daily maintenance and management. The microgrid distribution board is connected to the emergency distribution board via a point of common coupling (PCC) device. The PCC device mainly consists of a grid-connected converter and protection devices. The PCC device is the core equipment used to maintain the grid connection safety of both the auxiliary power grid and the microgrid, resolving the dynamic characteristic differences between the two grids, achieving safe and stable power exchange between the two grids, and supporting flexible switching of operating modes.

[0034] The wind turbine generator sets in this embodiment adopt an independent grid-connected scheme. Each wind turbine generator set is equipped with a separate wind power grid-connected converter, and each wind turbine can be controlled independently. In this embodiment, the rotary wind turbine generator FG1 is connected to the wind power grid-connected converter 1 through circuit breaker MCB1, and then connected to the AC400V busbar of the microgrid distribution board through circuit breaker MCB2; the rotary wind turbine generator FG2 is connected to the wind power grid-connected converter 2 through circuit breaker MCB4, and then connected to the AC400V busbar of the microgrid distribution board through circuit breaker MCB3.

[0035] Flexible photovoltaic modules with a single unit power of 520W were selected, with each module measuring approximately 2200mm × 1180mm × 2.5mm, and a total of 1900 modules were installed. The photovoltaic grid connection adopted a three-tiered access architecture: "zonal combiner - centralized inverter - DC voltage regulation - AC grid connection". The 1900 modules were divided into 19 combiner units according to their installation areas, and the combiner units were located in appropriate locations such as the distribution boxes on each floor of the ship. Each unit was equipped with one DC combiner cabinet. The 19 combiner cabinets were connected to three 350kW photovoltaic inverters, converting DC power into three-phase AC power of 400V / 50Hz. The three grid-connected inverters were connected to the microgrid through circuit breakers.

[0036] All of the ship's approximately 590kW of critical AC220V loads and 90kW of emergency AC220V loads are connected to a microgrid, powered by the microgrid distribution board GMSB. A 400V / 230V transformer T7 is installed in the microgrid. Its primary side is connected to the microgrid's 400V busbar via circuit breaker MCB7, and its secondary side is connected to the microgrid's 230V load panel busbar via circuit breaker MCB8. Additionally, the 230V busbar is also connected to the forward power station's AC230V busbar via circuit breaker ACB26. Under normal circumstances, AC230V power is supplied by the transformer T7 branch. If this power supply branch fails, the power automatically switches to the forward power station's supply branch.

[0037] Example 2 To optimize the power supply mode of large cruise ships under various operating conditions, improve energy utilization efficiency, and ensure the safety of the ship's power system in this embodiment, the operating mode of this embodiment is proposed based on the characteristics of the integrated power system with dual power stations including microgrids.

[0038] This embodiment of the microgrid has two specific operation modes: grid-connected operation and off-grid operation. In grid-connected operation, there are two modes: forward power supply from the main power station and reverse power supply from the microgrid. Typical power supply operations for large cruise ships include: port entry / exit conditions; nighttime navigation conditions; cruising and entertainment conditions; maximum navigation conditions; nighttime anchoring conditions; docking conditions; and emergency conditions. During port entry and exit operations, the ship's propulsion load in this embodiment is approximately 7MW, the air conditioning load is approximately 5MW, other 380V equipment is approximately 4MW, and the 220V load is approximately 3MW. Based on this, the recommended operating mode for the power supply unit is: operate two main generator sets, one at each of the forward and aft power stations, or two at each station; close the medium-voltage distribution board's jumper switch. During port entry and exit, there may be obstructions and brief periods of strong topographic winds. The microgrid should prioritize stable operation, with wind turbines and photovoltaic power generation devices providing a small but relatively stable amount of power. Set the wind turbines to operate within 30%-45% of their rated power to stably utilize low-wind-speed energy. If sudden wind speed fluctuations occur, shut down the turbines immediately to minimize impact. Set the photovoltaic devices to a fixed output power, such as 30%-35% of their rated power.

[0039] During nighttime navigation at a cruising speed of 18 knots, the propulsion power is approximately 17MW, with a single propulsion system providing 8.5MW. In this embodiment, the large cruise ship has an occupancy rate of 90%, with an air conditioning load of approximately 10MW and other 380V equipment power of approximately 5MW. After cruising, cabin equipment usage is higher, with a 220V load of approximately 10.1MW. The total power is approximately 42.1MW. It is estimated that the wind and solar power installations will contribute 100kW to 245kW of power. The strategy adopted at this time is: wind power generation units operate at maximum power output + energy storage to smooth fluctuations + grid-connected and coordinated regulation with the main power station. Power balancing within the microgrid is prioritized, with any shortfall supplemented by the main power station.

[0040] Therefore, three main generators are needed, which can power one front (rear) power station and two rear (front) power stations. At night, sailing on the open sea, wind conditions are good and there are few obstructions.

[0041] During daytime cruising and recreational operation, the speed is 18 knots, with a propulsion power of approximately 17MW, and a single propulsion system providing 8.5MW. All major entertainment equipment is operational, cabin lighting requirements decrease slightly, and audio-visual equipment is running. Air conditioning load is approximately 11MW, other 380V equipment power is approximately 8MW, and the 220V load is approximately 11MW. Total power is approximately 47MW. Sailing on a wide expanse of sea, wind conditions are favorable with minimal obstruction, resulting in excellent solar energy acquisition. The strategy employed is: maximum power output from both wind and solar power generators, energy storage to mitigate fluctuations, and grid-connected regulation with the main power station. Priority is given to power balancing within the microgrid, with any shortfall supplemented by the main power station. Therefore, four main generators are required.

[0042] Under maximum operating conditions, the ship's speed is 22 knots, and the propulsion power requirement is approximately 34MW, with a single propulsion system providing 17MW. Maximum speed operation typically occurs only under special circumstances after the ship is put into operation. This embodiment considers the maximum scenario, where other load conditions are as follows: air conditioning load approximately 12MW, other 380V equipment power approximately 8MW, and 220V load approximately 11MW. The total power is approximately 65MW. At this time, all four main generator units of the forward and aft power stations need to be fully operational. Both wind and solar power generation devices are outputting maximum power.

[0043] During nighttime anchoring, propulsion loads are shut down, with only some auxiliary power equipment operating. Outdoor large-scale entertainment facilities are closed, while some cabin service facilities, communication equipment, air conditioning equipment, security monitoring equipment, and indoor entertainment equipment are operated. At this time, the air conditioning load is approximately 9MW, and the power of other 380V equipment is approximately 5.6MW. The 220V load is approximately 10.4MW. The total power is approximately 25MW. Based on this, one unit each from the forward and aft power stations can be operated; or two units from the forward (or aft) power stations. The wind power generation unit is operated and outputs at maximum power.

[0044] Large cruise ships typically dock at piers with comprehensive safety measures in place. Therefore, when docked, piers equipped with shore power facilities are directly powered by shore power.

[0045] Emergency operating conditions are divided into two scenarios: main power station power failure (emergency scenario 1) and microgrid power failure (emergency scenario 2). Main power station power failure includes dual power station power failure or medium-voltage switchboard failure. In this case, the main diesel generator unit is no longer in hot standby mode, and all main diesel generator units must be shut down. The standby / emergency generator unit must be started. At this time, the standby / emergency generator unit continues to operate in grid connection with the microgrid through the emergency switchboard and PCC.

[0046] In Emergency Condition 2, the PCC must be immediately disconnected, the wind and solar power generation units and the bidirectional energy storage devices must cease operation, and the load in the microgrid must be reconfigured to power supply branches. The main power plant units generally maintain their current operating status.

[0047] Based on the above analysis, the operation mode of Example 2 can be given as shown in the table below.

[0048] .

[0050] The embodiments described above merely illustrate specific implementations of the present invention, and while the descriptions are detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A dual-power station integrated shipboard power system with microgrid, characterized in that, include: The forward and aft main power stations are installed on the ship, and the forward and aft main power stations are equipped with the same number and type of main diesel generator sets, respectively. The front and rear main power stations are each equipped with a medium-voltage main switchboard with a rated voltage of AC 6.6kV, used to supply power to the electric propulsion unit, side thrust motor, and downstream auxiliary power grid; the AC 6.6kV busbars of the front and rear main switchboards are connected by jumper wires; the auxiliary power grid includes two voltage levels, AC 400V and AC 230V, supplied by the medium-voltage main switchboards after being stepped down by AC 6.6kV / AC 400V transformers, and the AC 400V busbars of the front and rear main switchboards are also connected by jumper wires; the microgrid, internally... It includes a two-level power distribution system of AC400V and AC230V, equipped with a microgrid distribution board, a point of common coupling (PCC), wind power generation devices, photovoltaic power generation devices, a bidirectional energy storage system, and AC400V / AC230V transformers. The microgrid is connected to the AC400V busbar of the emergency distribution board through the PCC, and is also connected to the AC230V busbar of the main distribution board via a jumper wire as a backup power supply branch. Under normal operating conditions, the microgrid operates in parallel with the auxiliary power grid, and switches operating modes when the main power station or the microgrid fails.

2. The integrated shipboard power system with dual power stations and microgrid as described in claim 1, characterized in that, The wind power generation device is a rotary wind turbine, and the photovoltaic power generation device uses flexible thin-film photovoltaic modules, which are installed on the outer wall of the hull or below the passenger cabin balcony.

3. The integrated shipboard power system with dual power stations and microgrid as described in claim 1, characterized in that, The bidirectional energy storage system includes a lithium iron phosphate battery pack with a rated voltage of DC560V and a matching bidirectional fast converter, which is used to smooth microgrid power fluctuations and maintain dynamic stability of AC400V bus voltage.

4. The integrated shipboard power system with dual power stations and microgrid as described in claim 1, characterized in that, The AC400V busbar of the microgrid distribution board is divided into three sections by a disconnecting switch, which are used to connect to wind power generation devices, loads and energy storage systems, and photovoltaic power generation devices, respectively.

5. The integrated shipboard power system with microgrid and dual power stations as described in claim 1, characterized in that, The auxiliary power grid side of the main power station is also equipped with a parking and emergency diesel generator set. This unit starts when the main power station fails to supply power and operates in parallel with the microgrid through the emergency distribution board and PCC.

6. The integrated shipboard power system with dual power stations and microgrid as described in claim 1, characterized in that, The system executes different operating strategies based on the ship's operating conditions, including: port entry and exit, night navigation, cruise and recreation, maximum navigation, night anchoring, dock berthing, and emergency conditions. Under different operating conditions, the number of main generator sets started and stopped, the operating status of wind and solar power generation devices, the microgrid's grid connection / off-grid status, and the energy storage system's operating mode are adjusted accordingly.

7. The integrated shipboard power system with microgrid and dual power stations according to claim 6, characterized in that, When the system is berthed at the dock, it is powered by shore power. In the emergency situation of microgrid power failure, the PCC is immediately disconnected, the wind and solar power generation and energy storage system are stopped, and the power supply to the main power station or the front main distribution board is switched to AC230V for important loads.

8. The integrated shipboard power system with dual power stations and microgrid as described in claim 1, characterized in that, The AC6.6kV / AC400V daily service transformer serves as a backup for each other between the front and rear substations and achieves open-loop operation through circuit breaker interlocking logic.

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