A port shore power hybrid microgrid system

Abstract

The utility model belongs to the field of power generation and energy storage control technology, specifically discloses a kind of port shore power hybrid microgrid system. Including the medium voltage work section of being connected in grid in commercial power grid, medium voltage work section is connected wind power source and AC looped network cabinet through different transformer respectively, AC looped network cabinet is connected with low voltage DC work bus section through bidirectional DC / AC converter, and be connected with low voltage AC work bus section through transformer;DC work bus section is electrically connected with photovoltaic power generation system and battery through different DC / DC converter respectively;Low voltage AC work bus section is used to provide port power supply and charge passenger car battery.The scheme cooperates through reasonable topological structure and energy storage device, effectively suppresses power fluctuation, improves the stability and reliability of energy, realizes the efficient use of energy, so that ship can also economically use new energy such as photovoltaic, wind power, applicable to port shore power construction source-network-load-storage collaborative network.

Description

Technical Field

[0001] This utility model belongs to the field of power generation and energy storage control technology, and specifically discloses a port area shore power hybrid microgrid system. Background Technology

[0002] With the continued growth of global energy demand and the increasing prominence of environmental problems, traditional energy supply models are facing severe challenges. Against this backdrop, developing renewable energy, improving energy efficiency, and building intelligent and reliable energy systems have become a global consensus in the energy sector. Distributed energy sources, such as solar and wind power, are widely used due to their clean and renewable advantages, but they suffer from intermittency, volatility, and dispersed distribution. Microgrids, as small-scale power supply and utilization systems that integrate distributed energy sources, energy storage devices, loads, and control and protection devices, can effectively manage distributed energy sources and improve energy efficiency and power supply reliability.

[0003] In the development of microgrids, AC microgrids were the first to be applied. Their AC voltage can be easily converted to higher voltage levels using AC transformers. Distributed power sources such as photovoltaics and wind turbines, along with related energy storage devices, are all connected to a single AC bus within the microgrid system for unified dispatch through their respective matching converters. However, with the increasing presence of DC loads such as data centers and electric vehicle charging stations, DC microgrids are gradually gaining attention. They reduce multiple AC / DC conversions, improving power supply reliability and efficiency.

[0004] Hybrid AC / DC microgrids combine the advantages of both AC and DC microgrids. They can directly connect to both AC distributed power sources and AC loads, as well as DC distributed power sources and DC loads, eliminating the need for unnecessary power conversion. This reduces AC / DC or DC / AC converter stages, lowers energy losses and equipment costs, and also suppresses harmonics, improving system reliability. They can flexibly connect to various distributed energy sources, achieving optimized energy allocation. Energy storage devices can also be flexibly connected to AC or DC buses based on their own characteristics, storing and releasing energy when energy supply and demand are unbalanced, ensuring stable microgrid operation.

[0005] In port environments, there are high requirements for the reliability, stability, and energy efficiency of power supply. For example, the shore power system in a port area supplies power to ships at dock. Traditional methods are energy-intensive and polluting. Adopting AC / DC hybrid microgrid technology can effectively improve this situation. Port areas also contain various electrical equipment, including both AC and DC loads. AC / DC hybrid microgrids can better meet these diverse power demands. Simultaneously, the construction of the port's underground electrical system needs to be compatible with the overall power supply system. AC / DC hybrid microgrids can provide a stable power source for the underground electrical system, ensuring its normal operation.

[0006] Furthermore, wind power and solar power, as important renewable energy sources, occupy a significant position in the port area's energy structure. However, wind and solar energy are intermittent and fluctuating. Integrating them into an AC / DC hybrid microgrid, and effectively mitigating power fluctuations, improving energy stability and reliability, and achieving efficient energy utilization through a reasonable topology and energy storage devices, so that ships can economically utilize new energy sources such as solar and wind power, is a key problem that industry technicians urgently need to solve. Utility Model Content

[0007] To address the technical problems listed in the background section, this utility model provides a port area shore power hybrid microgrid system. The specific technical solution is as follows: A port area shore power hybrid microgrid system includes a municipal power grid, wind turbine generators, a photovoltaic power generation system, a medium-voltage operating section, a wind turbine box-type transformer, a first microgrid box-type transformer, a second microgrid box-type transformer, an AC ring network cabinet, a photovoltaic DC / DC converter, a bidirectional DC / AC converter, a multi-port bidirectional liquid-cooled DC supercharging terminal, a low-voltage DC operating bus section, and a low-voltage AC operating bus section. The municipal power grid is connected to the medium-voltage working section through the grid connection point; the wind turbine generator is connected to the low-voltage side of the wind turbine box-type transformer; the high-voltage side of the wind turbine box-type transformer is connected to the medium-voltage working section; the medium-voltage working section is connected to the high-voltage side of the first microgrid box-type transformer; the low-voltage side of the first microgrid box-type transformer is connected to the AC side of the bidirectional DC / AC converter through the AC ring network cabinet; the DC side of the bidirectional DC / AC converter is connected to the low-voltage DC working bus section; the photovoltaic power generation system is connected to the low-voltage DC working bus section through the photovoltaic DC / DC converter; the low-voltage DC working bus section is connected to the electric heavy truck battery and the electric ship battery respectively through the multi-port bidirectional liquid-cooled DC supercharging terminal; the low-voltage side of the first microgrid box-type transformer is connected to the high-voltage side of the second microgrid box-type transformer through the AC ring network cabinet; the low-voltage side of the second microgrid box-type transformer is connected to the low-voltage AC working bus section; the low-voltage AC working bus section is used to provide power to the port area load and station load, and is connected to the passenger car battery through the bidirectional AC supercharging terminal.

[0008] Preferably, the wind turbine box-type transformer is a double-winding step-up transformer. When the wind turbine generator is generating electricity, the wind turbine generator provides power to the medium-voltage working section through the wind turbine box-type transformer.

[0009] Preferably, the first microgrid box-type transformer adopts a dual-winding transformer, which serves as both a step-up transformer and a step-down transformer. When electric heavy truck batteries, electric ship batteries, station loads, port loads, and household vehicle batteries need to be charged, the first microgrid box-type transformer acts as a step-down transformer. When electric heavy truck batteries, electric ship batteries, and household vehicle batteries are used to provide peak-shaving power or frequency regulation power to the municipal power grid, the first microgrid box-type transformer acts as a step-up transformer.

[0010] Preferably, the second microgrid transformer adopts a dual-winding transformer, which serves as both a step-up transformer and a step-down transformer. When the household vehicle battery needs to be charged, the second microgrid transformer acts as a step-down transformer. When the household vehicle battery is used to provide peak-shaving or frequency-regulating power to the mains power grid, the second microgrid transformer acts as a step-up transformer.

[0011] Preferably, the bidirectional DC / AC converter has reactive power compensation and harmonic mitigation functions. When the electric heavy truck battery or electric ship battery needs to be charged, the bidirectional DC / AC converter can convert the AC power supply on the low-voltage side of the first microgrid transformer into DC power supply and send it to the low-voltage DC working bus. When the electric heavy truck battery or electric ship battery is used to provide peak-shaving power or frequency-regulating power to the mains power grid, the bidirectional DC / AC converter can convert the DC power supply on the low-voltage DC working bus into AC power supply and send it to the low-voltage side of the first microgrid transformer.

[0012] Preferably, the photovoltaic DC / DC converter is a unidirectional converter with reactive power compensation and harmonic mitigation functions.

[0013] Preferably, the multi-port bidirectional liquid-cooled DC supercharging terminal is a bidirectional multi-port photovoltaic DC / DC converter, which can adjust the output voltage and output power for charging and discharging different objects such as electric heavy-duty truck batteries and electric ship batteries. When the electric heavy-duty truck batteries and electric ship batteries need to be charged, the low-voltage DC working bus can charge the electric heavy-duty truck batteries and electric ship batteries through the multi-port bidirectional liquid-cooled DC supercharging terminal. When receiving grid frequency regulation or peak regulation commands, the multi-port bidirectional liquid-cooled DC supercharging terminal can control the output power of the electric heavy-duty truck batteries and electric ship batteries and the switching of batteries.

[0014] Preferably, the AC ring main unit has a one-in-multiple-out structure, with its inlet side connected to the low-voltage side of the first micro-grid transformer and its outlet side connected to the AC side of multiple bidirectional DC / AC converters and the high-voltage side of the second micro-grid transformer.

[0015] Preferably, the low-voltage side of the first microgrid transformer and the high-voltage side of the second microgrid transformer have the same voltage level, and the capacity of the first microgrid transformer is greater than that of the second microgrid transformer.

[0016] Compared with the prior art, this utility model has the following advantages: This utility model provides a port area shore power hybrid microgrid system. This system can solve the bottleneck of "difficulty in using green electricity" for electric ships, effectively reduce the carbon emissions of electric ships throughout their entire life cycle, significantly increase the economic added value of electric ship box power supplies, promote the development of port shore power systems and green electric ships, and accelerate the realization of the carbon neutrality goal of inland waterway shipping.

[0017] By establishing a power interaction channel between the electric ship's box-type power system and the grid power, the ship's battery can participate in grid frequency regulation or peak shaving services, effectively smoothing power fluctuations, improving energy stability and reliability, and achieving efficient energy utilization. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the power architecture of the port area shore power hybrid microgrid system in this embodiment of the present invention; Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be described below in conjunction with the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on these embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0020] Reference manual attached Figure 1 This embodiment provides a port area shore power hybrid microgrid system, including: a municipal power grid, wind turbine generators (multiple 6.25MW wind turbines connected in parallel), a photovoltaic power generation system, a medium-voltage operating section (10kV), wind turbine box-type transformers (7MW each), multiple first microgrid box-type transformers (3150KW-10KV / 0.8KV), multiple AC ring main units (0.8KV), a second microgrid box-type transformer (0.8~0.4KV), photovoltaic DC / DC converters (500~1500V / 750V), bidirectional DC / AC converters (DC-50~1000V / AC-0.8KV), multi-port bidirectional liquid-cooled DC supercharging terminals, a low-voltage DC operating bus section (750V), and a low-voltage AC operating bus section (380V or 220V). The municipal power grid is connected to the medium-voltage working section through the grid connection point; the wind turbine generator is connected to the low-voltage side of the wind turbine box transformer; the high-voltage side of the wind turbine box transformer is connected to the medium-voltage working section; the wind turbine box transformer is a double-winding step-up transformer, and when the wind turbine generator generates electricity, the wind turbine generator provides power to the medium-voltage working section through the wind turbine box transformer.

[0021] The medium-voltage working section is connected to the high-voltage side of the first microgrid transformer box. The first microgrid transformer box adopts a double-winding transformer, which serves as both a step-up transformer and a step-down transformer. When electric heavy truck batteries, electric ship batteries, as well as station loads, port loads, and household vehicle batteries need to be charged, the first microgrid transformer box acts as a step-down transformer. When electric heavy truck batteries, electric ship batteries, and household vehicle batteries are used to provide peak-shaving power or frequency regulation power to the municipal power grid, the first microgrid transformer box acts as a step-up transformer.

[0022] The low-voltage side of the first microgrid transformer is connected to the AC side of the bidirectional DC / AC converter via an AC ring network cabinet; the DC side of the bidirectional DC / AC converter is connected to the low-voltage DC working bus section; the bidirectional DC / AC converter has reactive power compensation and harmonic control functions. When the batteries of electric heavy trucks and electric ships need to be charged, the bidirectional DC / AC converter can convert the AC power on the low-voltage side of the first microgrid transformer into DC power and send it to the low-voltage DC working bus. When the batteries of electric heavy trucks and electric ships are used to provide peak-shaving power or frequency regulation power to the municipal power grid, the bidirectional DC / AC converter can convert the DC power on the low-voltage DC working bus into AC power and send it to the low-voltage side of the first microgrid transformer.

[0023] The photovoltaic power generation system is connected to the low-voltage DC working bus section via a photovoltaic DC / DC converter. The photovoltaic DC / DC converter is a unidirectional converter with reactive power compensation and harmonic mitigation functions. The low-voltage DC working bus section is connected to the electric heavy-duty truck battery and the electric ship battery respectively through a multi-port bidirectional liquid-cooled DC supercharging terminal. The multi-port bidirectional liquid-cooled DC supercharging terminal is a bidirectional multi-port photovoltaic DC / DC converter, which can adjust the output voltage and output power for charging and discharging different objects such as electric heavy-duty truck batteries and electric ship batteries. When the electric heavy-duty truck batteries and electric ship batteries need to be charged, the low-voltage DC working bus can charge the electric heavy-duty truck batteries and electric ship batteries through the multi-port bidirectional liquid-cooled DC supercharging terminal. When receiving grid frequency regulation or peak regulation commands, the multi-port bidirectional liquid-cooled DC supercharging terminal can control the output of the electric heavy-duty truck batteries and electric ship batteries and the battery switching.

[0024] The low-voltage side of the first microgrid transformer is connected to the high-voltage side of the second microgrid transformer via an AC ring main unit. The AC ring main unit has a one-in-multiple-out structure; its incoming line is connected to the low-voltage side of the first microgrid transformer, and its outgoing line is connected to the AC side of multiple bidirectional DC / AC converters and the high-voltage side of the second microgrid transformer. The low-voltage side of the first microgrid transformer and the high-voltage side of the second microgrid transformer have the same voltage level, and the capacity of the first microgrid transformer is greater than that of the second microgrid transformer.

[0025] The low-voltage side of the second microgrid transformer is connected to the low-voltage AC working bus section; the low-voltage AC working bus section is used to provide power to the port area load and station load, and is connected to the passenger car battery through a bidirectional AC supercharging terminal.

[0026] The second microgrid transformer adopts a dual-winding transformer, which serves as both a step-up transformer and a step-down transformer. When the battery of a household vehicle needs to be charged, the second microgrid transformer acts as a step-down transformer. When the battery of a household vehicle is used to provide peak-shaving power or frequency regulation power to the mains power grid, the second microgrid transformer acts as a step-up transformer.

[0027] Finally, it should be noted that the above are merely preferred embodiments of this utility model and are not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A port area shore power hybrid microgrid system, characterized in that, include: Municipal power grid, wind turbine generator set, photovoltaic power generation system, medium-voltage working section, wind power box-type transformer, first microgrid box-type transformer, second microgrid box-type transformer, AC ring network cabinet, photovoltaic DC / DC converter, bidirectional DC / AC converter, multi-port bidirectional liquid-cooled DC supercharging terminal, low-voltage DC working bus section, low-voltage AC working bus section; The municipal power grid is connected to the medium-voltage working section through the grid connection point; the wind turbine generator is connected to the low-voltage side of the wind turbine box-type transformer; the high-voltage side of the wind turbine box-type transformer is connected to the medium-voltage working section; the medium-voltage working section is connected to the high-voltage side of the first microgrid box-type transformer; the low-voltage side of the first microgrid box-type transformer is connected to the AC side of the bidirectional DC / AC converter through the AC ring network cabinet; the DC side of the bidirectional DC / AC converter is connected to the low-voltage DC working bus section; the photovoltaic power generation system is connected to the low-voltage DC working bus section through the photovoltaic DC / DC converter; the low-voltage DC working bus section is connected to the electric heavy truck battery and the electric ship battery respectively through the multi-port bidirectional liquid-cooled DC supercharging terminal; the low-voltage side of the first microgrid box-type transformer is connected to the high-voltage side of the second microgrid box-type transformer through the AC ring network cabinet; the low-voltage side of the second microgrid box-type transformer is connected to the low-voltage AC working bus section; the low-voltage AC working bus section is used to provide power to the port area load and station load, and is connected to the passenger car battery through the bidirectional AC supercharging terminal.

2. The port area shore power hybrid microgrid system according to claim 1, characterized in that, The wind turbine box-type transformer adopts a double-winding step-up transformer. When the wind turbine generator is generating electricity, the wind turbine generator provides power to the medium-voltage working section through the wind turbine box-type transformer.

3. A port area shore power hybrid microgrid system according to claim 2, characterized in that, The first microgrid transformer adopts a dual-winding transformer, which serves as both a step-up transformer and a step-down transformer. When electric heavy truck batteries, electric ship batteries, as well as station loads, port loads, and household vehicle batteries need to be charged, the first microgrid transformer acts as a step-down transformer. When electric heavy truck batteries, electric ship batteries, and household vehicle batteries are used to provide peak-shaving or frequency-regulating power to the municipal power grid, the first microgrid transformer acts as a step-up transformer.

4. A port area shore power hybrid microgrid system as described in claim 3, characterized in that, The second microgrid transformer adopts a dual-winding transformer, which serves as both a step-up transformer and a step-down transformer. When the battery of a household vehicle needs to be charged, the second microgrid transformer acts as a step-down transformer. When the battery of a household vehicle is used to provide peak-shaving power or frequency regulation power to the mains power grid, the second microgrid transformer acts as a step-up transformer.

5. A port area shore power hybrid microgrid system as described in claim 4, characterized in that, The bidirectional DC / AC converter has reactive power compensation and harmonic mitigation functions. When the batteries of electric heavy-duty trucks and electric ships need to be charged, the bidirectional DC / AC converter can convert the AC power supply on the low-voltage side of the first microgrid transformer into DC power supply and send it to the low-voltage DC working bus. When the batteries of electric heavy-duty trucks and electric ships are used to provide peak-shaving power or frequency regulation power to the municipal power grid, the bidirectional DC / AC converter can convert the DC power supply on the low-voltage DC working bus into AC power supply and send it to the low-voltage side of the first microgrid transformer.

6. A port area shore power hybrid microgrid system as described in claim 5, characterized in that, A photovoltaic DC / DC converter is a unidirectional converter with reactive power compensation and harmonic mitigation functions.

7. A port area shore power hybrid microgrid system as described in claim 6, characterized in that, The multi-port bidirectional liquid-cooled DC supercharging terminal is a bidirectional multi-port photovoltaic DC / DC converter that can adjust the output voltage and output power for charging and discharging different types of batteries, such as those for electric heavy-duty trucks and electric ships. When the batteries for electric heavy-duty trucks and electric ships need charging, the low-voltage DC working bus can charge them through the multi-port bidirectional liquid-cooled DC supercharging terminal. When receiving grid frequency regulation or peak shaving commands, the multi-port bidirectional liquid-cooled DC supercharging terminal can control the output power and battery switching of the batteries for electric heavy-duty trucks and electric ships.

8. A port area shore power hybrid microgrid system as described in claim 7, characterized in that, The AC ring main unit has a one-in-multiple-out structure. Its incoming line side is connected to the low-voltage side of the first micro-grid transformer, and its outgoing line side is connected to the AC side of multiple bidirectional DC / AC converters and the high-voltage side of the second micro-grid transformer.

9. A port area shore power hybrid microgrid system as described in claim 8, characterized in that, The low-voltage side of the first microgrid transformer and the high-voltage side of the second microgrid transformer have the same voltage level, and the capacity of the first microgrid transformer is greater than that of the second microgrid transformer.

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