Offshore area multi-energy complementary power generation system and capacity configuration method thereof

Abstract

The offshore area multi-energy complementary power generation system comprises offshore wind power, a retaining dam is arranged on the side, close to the inland, of the offshore wind power, a lower reservoir is formed between the retaining dam and the inland through bottom digging, a water pump water-turbine generator set is arranged in the retaining dam, and the water pump water-turbine generator set communicates with seawater on the inner side and the outer side of the retaining dam; floating type photovoltaics are arranged on the sea surface around the offshore wind power generation system. The invention further discloses a capacity configuration method of the offshore area multi-energy complementary power generation system. The device is flexible in position arrangement, can be newly built, can also be arranged near an existing wind power plant, and is not limited by site selection; the water head difference of the upper and lower reservoirs is small, the requirement for sea pumping units is low, water conveying lines are short, and power station investment cost is low; the inland is not used in the upper library, extra land occupation is not needed, and land acquisition and immigrant cost is low.

Description

Technical Field

[0001] The invention relates to an offshore multi-energy complementary power generation system and a capacity configuration method thereof, belonging to the technical field of power systems. Background Art

[0002] In recent years, offshore wind power has developed rapidly in the eastern and southern coastal areas of my country, and the scale of installed capacity has expanded rapidly. Since wind power output is unstable and intermittent, it is necessary to match it with a storage system represented by pumped storage. Conventional offshore pumped storage power stations need to set up an upper reservoir at a higher inland position based on the coastal terrain, and use the ocean as a lower reservoir. The upper reservoir is usually a certain distance away from the coast, the water transmission line is long, the investment and construction cost is high, and the site selection is restricted by the inland coastal terrain. Therefore, a supporting sea pumping power station technology that is not constrained by the site is needed. Summary of the invention

[0003] The purpose of the present invention is to provide a multi-energy complementary power generation system in an offshore area, and also to provide a method for configuring the capacity of a multi-energy complementary power generation system in an offshore area. The present invention is flexible in configuration, is not restricted by site selection, and has a low investment cost for a power station.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: a multi-energy complementary power generation system in offshore areas, comprising: offshore wind power, wherein a dam is arranged on the inland side of the offshore wind power, the seabed is expanded between the dam and the inland to form a lower reservoir, a pump-turbine generator set is arranged in the dam, a plant can be arranged in the dam, and the pump-turbine generator set is installed in the plant, the pump-turbine generator set is connected to the seawater on both sides of the dam, and the ocean is used as an upper reservoir to form a pumped storage power station, and floating photovoltaics are arranged on the sea surface around the offshore wind power.

[0005] In the aforementioned offshore multi-energy complementary power generation system, the floating photovoltaic is fixed to the offshore wind power foundation by mooring cables to reduce the structural investment cost.

[0006] In the aforementioned offshore multi-energy complementary power generation system, floating photovoltaics are also arranged on the sea surface in the lower reservoir to increase the utilization area.

[0007] The aforementioned multi-energy complementary power generation system for offshore areas, wherein the floating photovoltaic, offshore wind power, and pump-turbine generator sets are electrically connected to each other, and the floating photovoltaic, offshore wind power, and pump-turbine generator sets are all connected to the external power grid. The power generation of the floating photovoltaic and offshore wind power can provide power for the pump operating conditions of the pumped-storage power station composed of the pump-turbine generator sets. In order to make full use of tidal energy, the power generation period can be overlapped with the high tide period to the maximum extent, and the pumping period can be overlapped with the high tide period to the maximum extent.

[0008] A capacity configuration method for a multi-energy complementary power generation system in an offshore area comprises the following steps:

[0009] S1. Predict and calculate power load P L,t ;

[0010] S2. Predict and calculate wind power output power P W,t 、Photovoltaic power output P pv,t , and the output power of the pumped storage power station P hs,t ;

[0011] S3. Calculate the minimum system life cycle cost:

[0012] minC=min(C w +C pv +C ps )

[0013] Among them, C is the total initial investment and total operation and maintenance cost of the system, C w is the initial investment and operation and maintenance cost of the wind farm; C pv is the initial investment and operation and maintenance cost of photovoltaic power generation; C ps The initial investment and operation and maintenance costs of the pumped storage power station;

[0014] S4. Calculate the maximum wind and solar utilization rate, that is, the minimum wind and solar abandonment rate:

[0015]

[0016] in, represents the real-time wind abandonment rate at time t, Indicates the real-time abandoned light rate at time t;

[0017] S5. Calculate the minimum deviation between the power generation system output and load demand:

[0018]

[0019] S6. The goal is to minimize the system's full life cycle cost, maximize the utilization rate of wind and solar power, and minimize the deviation between total output and demand. The priority order of the three goals is from high to low, and ultimately determines the capacity configuration of the pumped storage power station.

[0020] In the aforementioned method for configuring the capacity of a multi-energy complementary power generation system in an offshore area, in step S2, the wind power output power P W,t 、Photovoltaic power output P pv,t Based on real-time weather and cloud map forecasts, the real-time output for the next 15 minutes can be predicted every 5 minutes within every 24 hours.

[0021] In the aforementioned method for configuring the capacity of a multi-energy complementary power generation system in an offshore area, the aforementioned timing period T can be targeted at days, months, seasons, and years respectively.

[0022] In the aforementioned capacity configuration method of a multi-energy complementary power generation system in an offshore area, when calculating the output power of the pumped-storage power station, the system output is positive in the power generation condition and negative in the pumping condition.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] (1) The present invention has flexible location layout, and can be newly built or set up near an existing wind farm, without being restricted by site selection;

[0025] (2) The water head difference between the upper and lower reservoirs of the present invention is small, the requirements for the sea pumping unit are low, the water transmission line is short, and the investment cost of the power station is low;

[0026] (3) The upper reservoir of the present invention does not utilize inland areas, does not require additional land, and has low land acquisition and resettlement costs;

[0027] (4) For this system, the capacity configuration method of the present invention can be based on wind power capacity configuration, supplemented by photovoltaic capacity configuration, with the goal of minimizing the system's life cycle cost, maximizing wind and solar utilization, and minimizing the deviation between total output and demand. The capacity configuration of the pumped storage power station is ultimately determined, which can maximize savings in construction and operating costs and improve energy utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a system schematic diagram of the present invention;

[0029] Figure 2 It is a calculation flow chart of the present invention.

[0030] Figure numerals: 1-offshore wind power, 2-inland, 3-dam, 4-lower reservoir, 5-pump turbine generator set, 6-floating photovoltaic.

[0031] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. DETAILED DESCRIPTION

[0032] Embodiment 1 of the present invention: A multi-energy complementary power generation system in offshore areas, comprising: an offshore wind power 1, wherein a water retaining dam 3 is arranged on the side of the offshore wind power 1 close to the inland 2, the seabed is expanded between the water retaining dam 3 and the inland 2 to form a lower reservoir 4, a water pump and water turbine generator set 5 is arranged in the water retaining dam 3, a factory building can be arranged in the dam of the water retaining dam 3, and the water pump and water turbine generator set 5 is installed in the factory building, the water pump and water turbine generator set 5 is connected to the seawater on both sides of the water retaining dam 3, and the ocean is used as an upper reservoir to form a pumped storage power station, and floating photovoltaic 6 is arranged on the sea surface around the offshore wind power 1.

[0033] Embodiment 2 of the present invention: A multi-energy complementary power generation system in offshore areas, comprising: an offshore wind power 1, wherein a water retaining dam 3 is arranged on the side of the offshore wind power 1 close to the inland 2, the seabed is expanded between the water retaining dam 3 and the inland 2 to form a lower reservoir 4, a water pump and water turbine generator set 5 is arranged in the water retaining dam 3, a plant can be arranged in the dam of the water retaining dam 3, and the water pump and water turbine generator set 5 is installed in the plant, the water pump and water turbine generator set 5 connects the seawater on both sides of the water retaining dam 3, and uses the ocean as an upper reservoir to form a pumped storage power station, floating photovoltaics 6 are arranged on the sea surface around the offshore wind power 1, and the floating photovoltaics 6 are fixed to the foundation of the offshore wind power 1 by mooring cables to reduce the structural investment cost, and floating photovoltaics 6 are also arranged on the sea surface in the lower reservoir 4 to increase the utilization area, and the floating photovoltaics 6 in the lower reservoir 4 can be fixed by setting a base at the bottom of the lower reservoir 4 or on the dam body.

[0034] Embodiment 3 of the present invention: A multi-energy complementary power generation system in offshore areas, comprising: an offshore wind power 1, wherein a water retaining dam 3 is arranged on the side of the offshore wind power 1 close to the inland 2, the seabed is expanded between the water retaining dam 3 and the inland 2 to form a lower reservoir 4, a water pump and water turbine generator set 5 is arranged in the water retaining dam 3, a plant can be arranged in the dam of the water retaining dam 3, and the water pump and water turbine generator set 5 is installed in the plant, the water pump and water turbine generator set 5 connects the seawater on both sides of the water retaining dam 3, and uses the ocean as an upper reservoir to form a pumped storage power station, floating photovoltaics 6 are arranged on the sea surface around the offshore wind power 1, and the floating photovoltaics 6 are fixed to the foundation of the offshore wind power 1 by mooring cables to reduce the structural investment cost, and floating photovoltaics 6 are also arranged on the sea surface in the lower reservoir 4 to increase the utilization area, and the floating photovoltaics 6 in the lower reservoir 4 can be fixed by setting a base at the bottom of the lower reservoir 4 or on the dam body.

[0035] The floating photovoltaic 6, offshore wind power 1, and pump-turbine generator set 5 are electrically connected to each other, and the floating photovoltaic 6, offshore wind power 1, and pump-turbine generator set 5 are all connected to the external power grid. The power generation of the floating photovoltaic 6 and offshore wind power 1 can provide power for the pump working condition of the pumped storage power station composed of the pump-turbine generator set 5. In order to make full use of tidal energy, the power generation period can be overlapped with the high tide period to the maximum extent, and the pumping period can be overlapped with the high tide period to the maximum extent.

[0036] Embodiment 4 of the present invention: A method for configuring the capacity of a multi-energy complementary power generation system in an offshore area, comprising the following steps:

[0037] S1. Predict and calculate power load P L,t .

[0038] S2. Predict and calculate wind power output P W,t 、Photovoltaic power output P pv,t , and the output power of the pumped storage power station P hs,t .

[0039] S3. Calculate the minimum system life cycle cost:

[0040] minC=min(C w +C pv +C ps )

[0041] Among them, C is the total initial investment and total operation and maintenance cost of the system, C w is the initial investment and operation and maintenance cost of the wind farm; C pv is the initial investment and operation and maintenance cost of photovoltaic power generation; C ps It is the initial investment and operation and maintenance cost of the pumped storage power station.

[0042] S4. Calculate the maximum wind and solar utilization rate, that is, the minimum wind and solar abandonment rate:

[0043]

[0044] Among them, represents the real-time wind abandonment rate at time t, and represents the real-time solar abandonment rate at time t.

[0045] S5. Calculate the minimum deviation between the power generation system output and load demand:

[0046]

[0047] S6. The goal is to minimize the system's full life cycle cost, maximize the utilization rate of wind and solar power, and minimize the deviation between total output and demand. The priority order of the three goals is from high to low, and ultimately determines the capacity configuration of the pumped storage power station.

[0048] Embodiment 5 of the present invention: A capacity configuration method for a multi-energy complementary power generation system in an offshore area, comprising the following steps:

[0049] S1. Predict and calculate power load P L,t .

[0050] S2. Predict and calculate wind power output P W,t 、Photovoltaic power output P pv,t , and the output power of the pumped storage power station Phs,t .

[0051] Among them, the wind power output power P W,t 、Photovoltaic power output P pv,t Based on real-time meteorological and cloud map forecasts, the real-time output of the next 15 minutes can be predicted every 5 minutes within every 24 hours; at the same time, when calculating the output power of the pumped-storage power station, the system output is positive in the power generation condition and negative in the pumping condition.

[0052] S3. Calculate the minimum system life cycle cost:

[0053] minC=min(C w +C pv +C ps )

[0054] Among them, C is the total initial investment and total operation and maintenance cost of the system, C w is the initial investment and operation and maintenance cost of the wind farm; C pv is the initial investment and operation and maintenance cost of photovoltaic power generation; C ps The initial investment and operation and maintenance costs of the pumped storage power station;

[0055] S4. Calculate the maximum wind and solar utilization rate, that is, the minimum wind and solar abandonment rate:

[0056]

[0057] Among them, represents the real-time wind curtailment rate at time t, represents the real-time solar curtailment rate at time t;

[0058] S5. Calculate the minimum deviation between the power generation system output and load demand:

[0059]

[0060] S6. The goal is to minimize the system's full life cycle cost, maximize the utilization rate of wind and solar power, and minimize the deviation between total output and demand. The priority order of the three goals is from high to low, and ultimately determines the capacity configuration of the pumped storage power station.

[0061] The above-mentioned timing period T can be targeted at day, month, season or year respectively.

[0062] The working principle of an embodiment of the present invention: The present invention consists of three parts: an offshore wind power plant 1, a floating photovoltaic 6, and a pump-turbine generator set 5. A dam 3 is set on the inland side 2 of the existing offshore wind power plant 1, and a factory building is set in the dam. The factory building is equipped with a pump-turbine generator set 5. The seabed is expanded on the inland side 2 of the dam 3 as a lower reservoir 4, and the ocean is used as an upper reservoir. Floating photovoltaic 6 is set around the offshore wind power plant 1 and in the lower reservoir 4; the offshore wind power 1 and floating photovoltaic 6 power generation can provide power for the sea pump working condition. In order to make full use of tidal energy, the power generation period can be overlapped with the high tide period to the maximum extent, and the pumping period can be overlapped with the high tide period to the maximum extent.

[0063] For the above system, considering that the construction cost of offshore pumped storage power stations is relatively high, the wind power capacity configuration can be used as the basis, supplemented by photovoltaic capacity configuration, with the goal of minimizing the system's life cycle cost, maximizing the utilization rate of wind and solar power (minimizing the amount of abandoned wind and solar power), and minimizing the deviation between total output and demand. The priority order of the above three objectives is from high to low, and ultimately determines the capacity configuration of the pumped storage power station. When solving the multi-objective optimal solution, the constraints are set.

Claims

1. A multi-energy complementary power generation system in offshore areas, characterized in that: include: An offshore wind power plant (1), wherein a water retaining dam (3) is arranged on the side of the offshore wind power plant (1) close to an inland area (2), a lower reservoir (4) is formed between the water retaining dam (3) and the inland area (2) by digging down the bottom, a water pump and water turbine generator set (5) is arranged inside the water retaining dam (3), and the water pump and water turbine generator set (5) is connected to the seawater on both sides of the water retaining dam (3), and floating photovoltaic (6) is arranged on the sea surface around the offshore wind power plant (1).

2. The offshore multi-energy complementary power generation system according to claim 1, characterized in that: The floating photovoltaic (6) is fixed on the foundation of the offshore wind power (1) via a mooring cable.

3. The offshore multi-energy complementary power generation system according to claim 2, characterized in that: A floating photovoltaic system (6) is also provided on the sea surface in the lower reservoir (4).

4. The offshore multi-energy complementary power generation system according to claim 3, characterized in that: The floating photovoltaic (6), offshore wind power (1), and water pump turbine generator set (5) are electrically connected to each other, and the floating photovoltaic (6), offshore wind power (1), and water pump turbine generator set (5) are all connected to an external power grid.

5. A method for configuring the capacity of a multi-energy complementary power generation system in an offshore area according to claims 1-4, characterized in that: The following steps are involved: S1. Predict and calculate power load P L,t ; S2. Predict and calculate wind power output P W,t 、Photovoltaic power output P pv,t , and the output power of the pumped storage power station P hs,t ; S3. Calculate the minimum system life cycle cost: minC=min(C w +C pv +C ps ) Among them, C is the total initial investment and total operation and maintenance cost of the system, Cw is the initial investment and operation and maintenance cost of the wind farm; Cpv is the initial investment and operation and maintenance cost of photovoltaic power station; Cps is the initial investment and operation and maintenance cost of pumped storage power station; S4. Calculate the maximum wind and solar utilization rate, that is, the minimum wind and solar abandonment rate: in, represents the real-time wind abandonment rate at time t, Indicates the real-time abandoned light rate at time t; S5. Calculate the minimum deviation between the power generation system output and load demand: S6. The goal is to minimize the system's full life cycle cost, maximize the utilization rate of wind and solar power, and minimize the deviation between total output and demand. The priority order of the three goals is from high to low, and ultimately determines the capacity configuration of the pumped storage power station.

6. A method for configuring the capacity of a multi-energy complementary power generation system in an offshore area according to claim 5, characterized in that: In step S2, the wind power output power P W,t 、Photovoltaic power output P pv,t Based on real-time weather and cloud map forecasts, the real-time output for the next 15 minutes can be predicted every 5 minutes within every 24 hours.

7. A method for configuring the capacity of a multi-energy complementary power generation system in an offshore area according to claim 6, characterized in that: The above-mentioned timing period T can be targeted at day, month, season or year respectively.

8. The method for configuring the capacity of a multi-energy complementary power generation system in an offshore area according to claim 7, characterized in that: When calculating the output power of the pumped storage power station, the system output is positive in the power generation condition and negative in the pumping condition.

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