An integrated ac-dc shore power system

Abstract

This utility model relates to an integrated AC / DC shore power system, comprising an AC / DC bidirectional rectifier unit connected to the mains power supply and an energy storage unit. The output of the AC / DC bidirectional rectifier unit is connected via a DC bus to a DC / AC inverter unit, a DC / DC converter unit, and the energy storage unit. This allows the DC power output from the AC / DC bidirectional rectifier unit to be converted into AC power via the DC / AC inverter unit, or into DC power via the DC / DC converter unit, or directly stored in the energy storage unit. Advantages include: it can achieve multiple operating modes including DC power supply, AC power supply, and energy storage operation. This allows for charging of DC pure electric ships and DC hybrid ships using both DC and AC charging methods, as well as charging of the battery packs of electric ships using battery swapping, meeting the shore charging needs of different types of electric ships. It can also provide shore power for conventional fuel ships, reducing redundant investment in shore charging facilities for electric ships.

Description

Technical Field

[0001] This utility model relates to a shore power system, specifically an AC / DC integrated shore power system based on flexible DC bus output. Background Technology

[0002] In recent years, my country has vigorously constructed shore power facilities for ships, mainly for AC power supply to traditional fuel-powered ships berthing in port. The shore power supply method is singular and cannot meet the charging needs of different types of electric ships. With the development of new energy technologies, the number of electric ships is also gradually increasing. However, the power supply method of electric ships is different from that of conventional fuel-powered ships. Therefore, in order to meet the charging needs of electric ships, it is necessary to add shore power charging facilities for electric ships. This not only results in high equipment investment costs, but also low efficiency and poor economic performance of various shore power facilities. Summary of the Invention

[0003] The technical problem to be solved by this utility model is to provide an AC / DC integrated shore power system that can not only meet the shore charging needs of different types of electric ships, but also provide shore power for conventional fuel ships, reduce the repeated investment in shore power charging facilities for electric ships, and make full use of port shore power berths to improve the utilization efficiency of shore power facilities.

[0004] To solve the above-mentioned technical problems, the present invention provides an AC / DC integrated shore power system, which includes an AC / DC bidirectional rectifier unit connected to the mains power supply and an energy storage unit for energy storage. The output terminal of the AC / DC bidirectional rectifier unit is connected to a DC / AC inverter unit, a DC / DC converter unit and the energy storage unit via a DC bus, and enables the DC power output by the AC / DC bidirectional rectifier unit to output AC power through the DC / AC inverter unit, or to output DC power through the DC / DC converter unit, or to be directly stored in the energy storage unit.

[0005] The input terminal of the AC / DC bidirectional rectifier unit is connected to the mains power supply via the incoming line cabinet.

[0006] The DC / AC inverter unit includes a first DC EMI filter connected to the DC bus side, a first AC EMI filter located on the AC output side, an inverter circuit and an AC filter circuit connected sequentially between the first DC EMI filter and the first AC EMI filter.

[0007] The energy storage unit is an auxiliary power supply connected between the rear side of the DC EMI filter and the rear side of the AC EMI filter, respectively. The auxiliary power supply is connected to a power supply line located on the DC bus side for drawing power from the battery.

[0008] A pre-charge circuit is provided on the front side of the first DC EMI filter.

[0009] The DC-DC conversion unit includes a second DC EMI filter located on the low-voltage side of the DC, a third DC EMI filter located on the high-voltage side of the DC, and a bidirectional rectifier circuit connected between the second and third DC EMI filters.

[0010] A second pre-charge circuit is provided on the front side of the second DC EMI filter.

[0011] The advantages of this utility model are: Through the installation of power modules such as bidirectional rectifier modules, DC bus units, energy storage units, DC conversion units, and inverter units, multiple operating modes can be achieved, including DC power supply, AC power supply, and operational energy storage. This allows for charging of DC pure electric ships and DC hybrid ships using both DC and AC charging methods, as well as charging of the box-type power batteries in battery-swapping electric ships, thus meeting the shore-based charging needs of different types of electric ships. Simultaneously, it can also provide shore-based power supply for conventional fuel vessels, reducing redundant investment in shore power charging facilities for electric ships. Furthermore, it can fully utilize port shore power berths, improving the efficiency of shore power facilities and forming a highly safe, economical, and reliable shore-based power supply system for electric ships that is adaptable to various types of vessels. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the AC / DC integrated shore power supply system of this utility model; Figure 2 This is a circuit diagram of the DC / AC inverter unit in this utility model; Figure 3 This is a circuit diagram of the DC-DC conversion unit in this utility model. Detailed Implementation

[0013] The AC / DC integrated shore power supply system of this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0014] As shown in the figure, the AC / DC integrated shore power system of this utility model includes an AC / DC bidirectional rectifier unit connected to the mains power and an energy storage unit for energy storage. Figure 1As can be seen, the input terminal of the AC / DC bidirectional rectifier unit is connected to the mains power through the incoming line cabinet, and the output terminal of the AC / DC bidirectional rectifier unit is connected to the DC / AC inverter unit, the DC / DC DC conversion unit, and the energy storage unit through the DC bus. The DC / AC inverter unit includes a first DC EMI filter connected to the DC bus side, a first AC EMI filter located on the AC output side, an inverter circuit and an AC filter circuit connected sequentially between the first DC EMI filter and the first AC EMI filter. The energy storage unit is an auxiliary power supply connected between the downstream sides of the DC EMI filter and the AC EMI filter. As shown in the figure, the front end of the auxiliary power supply is connected to the two output lines of the first DC EMI filter. The back-end is connected to L1 and L2 respectively. The auxiliary power supply is also connected to a power line located on the DC bus side for battery power. As shown in the figure, the auxiliary power supply is connected to two DC input lines for battery power. The DC conversion unit includes a second DC EMI filter on the low-voltage side, a third DC EMI filter on the high-voltage side, and a bidirectional rectifier circuit connected between the second and third DC EMI filters. This allows the DC power output from the AC / DC bidirectional rectifier unit to output AC power through the DC / AC inverter unit, or DC power through the DC / DC conversion unit, or directly through the energy storage unit for energy storage. In the energy storage mode, the energy storage unit absorbs the reverse power generated during AC grid connection (such as...). Figure 2 (as shown) and limiting the DC overvoltage during DC charging (such as...) Figure 3 (As shown), to prevent energy feedback to the power grid from causing safety accidents.

[0015] Furthermore, a pre-charge circuit is provided on the front side of the first DC EMI filter, a pre-charge circuit is provided on the front side of the second DC EMI filter, and a pre-charge circuit is provided on the rear side of the third DC EMI filter.

[0016] Of course, the above description is not intended to limit the present utility model, and the present utility model is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present utility model should also fall within the protection scope of the present utility model.

Claims

1. An AC / DC integrated shore power system, characterized by: It includes an AC / DC bidirectional rectifier unit connected to the mains power supply and an energy storage unit for energy storage. The output terminal of the AC / DC bidirectional rectifier unit is connected to a DC / AC inverter unit, a DC / DC converter unit and the energy storage unit via a DC bus, and can enable the DC power output by the AC / DC bidirectional rectifier unit to output AC power through the DC / AC inverter unit, or to output DC power through the DC / DC converter unit, or to be stored directly in the energy storage unit. The energy storage unit is an auxiliary power supply connected between the rear side of the DC EMI filter and the rear side of the AC EMI filter, respectively. The auxiliary power supply is connected to a power supply line located on the DC bus side for drawing power from the battery.

2. The AC / DC integrated shore power system of claim 1, wherein: The input terminal of the AC / DC bidirectional rectifier unit is connected to the mains power supply via the incoming line cabinet.

3. The AC / DC integrated shore power system according to claim 1 or 2, characterized in that: The DC / AC inverter unit includes a first DC EMI filter connected to the DC bus side, a first AC EMI filter located on the AC output side, an inverter circuit and an AC filter circuit connected sequentially between the first DC EMI filter and the first AC EMI filter.

4. The AC / DC integrated shore power system according to claim 3, characterized in that: A pre-charge circuit is provided on the front side of the first DC EMI filter.

5. The AC / DC integrated shore power system according to claim 1, 2, or 4, characterized in that: The DC-DC conversion unit includes a second DC EMI filter located on the low-voltage side of the DC, a third DC EMI filter located on the high-voltage side of the DC, and a bidirectional rectifier circuit connected between the second and third DC EMI filters.

6. The AC / DC integrated shore power system according to claim 5, characterized in that: A second pre-charge circuit is provided on the front side of the second DC EMI filter.

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