Power distribution method based on wind-solar-storage micro-grid

Abstract

The invention discloses a power distribution method based on a wind and light storage micro-grid, and the method comprises the steps: obtaining wind power basic data and photovoltaic basic data, obtaining the wind power generation power based on the wind power basic data, and obtaining the photovoltaic power generation power based on the photovoltaic basic data; acquiring a user load condition, and when the total photovoltaic power generation power and the total wind power generation power are greater than the user load, calling power generation power consistent with the user load to supply power to the user load, charging an energy storage battery by using the residual power generation power, or selling residual electric energy to a power grid, or cutting off wind and light curtailment power; when the total power of photovoltaic power generation and the total power of wind power generation are smaller than the user load, all generated power is called to supply power to the user load, and in addition, the discharging process of an energy storage battery is carried out, or electricity is purchased from a power grid, or a standby power supply is switched on to supply power to fill the gap of the user load.

Description

Technical Field

[0001] The present invention relates to the technical field of power distribution, and in particular to a power distribution method based on a wind, solar and energy storage microgrid. Background Art

[0002] At present, with the increasing intelligence of power grids, power supply planning and means of various power grid forms are becoming more and more popular. As the types of power-consuming equipment continue to increase, the power demand for power grids is also increasing, and the peak and valley values ​​are more volatile. For each end of wind, solar, storage and charging, the management is configured separately according to their local operating conditions and load demand. How to carry out power regulation technology lacks coordination and globality. The corresponding decentralized management and control of a single source are not in place, which not only consumes a lot of investment costs, but also makes it difficult to achieve the expected results. For this reason, it is urgent to explore multi-source network collaborative planning and control technologies that can better improve the quality of power. Summary of the invention

[0003] In view of the above-mentioned prior art, the present invention provides a power distribution method based on a wind, solar and energy storage microgrid, which mainly solves the technical problems existing in the above-mentioned background technology.

[0004] To achieve the above object, the technical solution of the embodiment of the present invention is implemented as follows:

[0005] A power distribution method based on a wind, solar and energy storage microgrid, the power distribution method comprising:

[0006] Obtain wind power basic data and photovoltaic basic data, obtain wind power generation power based on wind power basic data, and obtain photovoltaic power generation power based on photovoltaic basic data;

[0007] Obtain the user load situation. When the total photovoltaic power generation and the total wind power generation are greater than the user load, the power generation consistent with the user load is called to realize the power supply of the user load, and the remaining power generation is used to charge the energy storage battery, or sell the remaining power to the power grid, or cut off the abandoned wind and photovoltaic power;

[0008] When the total photovoltaic power generation and the total wind power generation are less than the user load, all the generated power is used to supply power to the user load. In addition, the energy storage battery is discharged, or electricity is purchased from the grid, or a backup power supply is connected to fill the user load gap.

[0009] Optionally, the basic wind power data includes wind energy utilization coefficient, air density, wind rotor swept area, wind speed, wind turbine tip speed ratio and wind turbine blade moment angle. The wind power generation capacity of a single wind turbine is calculated by the following formula:

[0010]

[0011] Among them, Pm is the output power of the fan; c p is the wind energy utilization coefficient; ρ is the air density; A is the wind rotor swept area; v winds is the wind speed; λ is the fan blade tip speed ratio; β is the fan blade torque angle.

[0012] Optionally, calculate the total wind power by the following formula:

[0013] P feng =N WT ·P m (t)

[0014] N WT is the number of fans, P feng is the total wind power generation power, P m (t) is the power generation of a single wind turbine at time t.

[0015] Optionally, the photovoltaic basic data includes the peak power of the photovoltaic panel, the solar radiation correction factor, the conversion efficiency of the photovoltaic panel, the temperature coefficient of the photovoltaic panel, the actual ambient temperature and the temperature under standard test conditions. The power generation of a single photovoltaic panel is calculated by the following formula:

[0016] P pv =P max *F*η*(1-α*(TT STC )

[0017] Among them, P max is the peak power of the photovoltaic panel; F is the solar radiation correction factor; η is the conversion efficiency of the photovoltaic panel; α is the temperature coefficient of the photovoltaic panel; T is the actual ambient temperature; T STC is the temperature under standard test conditions.

[0018] Optionally, calculate the total photovoltaic power generation power by the following formula:

[0019] P guang =N PV ·P PV (t)

[0020] N PV is the number of photovoltaic panels, P guang is the total photovoltaic power generation power, P PV (t) is the power generation of a single photovoltaic panel at time t.

[0021] Optionally, the following formula is used to determine whether the total photovoltaic power generation and the total wind power generation meet the user load:

[0022] ΔP(t)=N WT ·P WT (t)+N PV ·PPV (t)-P load (t)

[0023] Where ΔP(t) is the differential load, P load (t) is the user load;

[0024] When ΔP(t)>0, it means that the total photovoltaic power generation and the total wind power generation are greater than the user load;

[0025] When ΔP(t)<0, it means that the total photovoltaic power generation power and the total wind power generation power are less than the user load.

[0026] Optionally, when the total photovoltaic power generation and the total wind power generation are greater than the user load, the charge state of the energy storage battery is judged to determine whether the maximum charging energy constraint is reached;

[0027] If the maximum charging energy constraint is not exceeded, the energy storage battery is charged;

[0028] If the energy limit of the energy storage is exceeded, the remaining electricity will be sold to the grid in the form of grid connection;

[0029] Eliminate abandoned wind and solar power in isolated island situations.

[0030] Optionally, when the total photovoltaic power generation and the total wind power generation are less than the user load, the charge state of the energy storage battery is judged to determine whether the minimum discharge energy constraint is reached;

[0031] If the minimum discharge energy constraint is not exceeded, the energy storage battery is discharged, and the energy storage battery is added to meet the supply of the user load;

[0032] If the minimum discharge energy constraint is exceeded, electricity will be purchased from the grid to meet the supply of the user's load in the grid-connected form.

[0033] The beneficial effects of the present invention are that it is easy to implement and master in actual engineering applications. By controlling the energy throughput of the energy storage system, the deviation between the output power of the wind-solar combined power generation and the planned power generation power of the wind-solar-storage microgrid power generation system can be compensated in real time, so that the power generation system is transformed from a power source with output fluctuating at any time to a power source with a certain output. The output power can be stabilized according to the power generation plan, and ultimately the effect of meeting user loads and reducing the amount of wind and solar power abandoned can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of a power distribution method based on a wind-solar-storage microgrid in an embodiment of the present application. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further elaborated in detail below in conjunction with the drawings and specific embodiments of the specification. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. In the following description, the expression "some embodiments" is related to a subset of all possible embodiments, but it should be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments, and can be combined with each other without conflict.

[0036] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0037] It should be understood that the present invention can be implemented in different forms and should not be interpreted as being limited to the embodiments proposed herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and the scope of the present invention will be fully conveyed to those skilled in the art. And the purpose of the terms used herein is only to describe specific embodiments and is not intended to be a limitation of the present invention. When used herein, the singular forms of "one", "one" and "said / the" are also intended to include plural forms, unless the context clearly indicates another way. It should also be understood that the terms "compose" and / or "include" when used in this specification determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0038] It should also be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "inside", "outside", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0039] In order to fully understand the present invention, a detailed structure will be proposed in the following description to illustrate the technical solution proposed by the present invention. The optional embodiments of the present invention are described in detail as follows, but in addition to these detailed descriptions, the present invention may also have other implementations.

[0040] Please refer to the attached Figure 1 The present application provides a power distribution method based on a wind-solar-storage microgrid, the power distribution method comprising:

[0041] S1. Obtain wind power basic data and photovoltaic basic data, obtain wind power generation power based on the wind power basic data, and obtain photovoltaic power generation power based on the photovoltaic basic data;

[0042] S2. Obtain the user load situation. When the total photovoltaic power generation and the total wind power generation are greater than the user load, the power generation consistent with the user load is called to realize the power supply of the user load, and the remaining power generation is used to charge the energy storage battery, or sell the remaining power to the power grid, or cut off the abandoned wind and photovoltaic power;

[0043] S3. When the total photovoltaic power generation and the total wind power generation are less than the user load, all the generated power is used to supply power to the user load. In addition, the energy storage battery is discharged, or electricity is purchased from the power grid, or a backup power supply is connected to supply power to fill the user load gap.

[0044] In a possible implementation, the basic wind power data includes wind energy utilization coefficient, air density, wind rotor swept area, wind speed, wind turbine tip speed ratio and wind turbine blade moment angle. The wind power generation power of a single wind turbine is calculated by the following formula:

[0045]

[0046] Among them, P m is the output power of the fan; c p is the wind energy utilization coefficient; ρ is the air density; A is the wind rotor swept area; v winds is the wind speed; λ is the fan blade tip speed ratio; β is the fan blade torque angle.

[0047] Furthermore, the total wind power generation power is calculated by the following formula:

[0048] P feng =N WT ·P m (t)

[0049] N WT is the number of fans, P feng is the total wind power generation power, P m (t) is the power generation of a single wind turbine at time t.

[0050] In one possible implementation, the photovoltaic basic data includes the peak power of the photovoltaic panel, the solar radiation correction factor, the conversion efficiency of the photovoltaic panel, the temperature coefficient of the photovoltaic panel, the actual ambient temperature, and the temperature under standard test conditions. The power generation of a single photovoltaic panel is calculated by the following formula:

[0051] P pv =P max *F*η*(1-α*(TT STC )

[0052] Where Pmax is the peak power of the photovoltaic panel; F is the solar radiation correction factor; η is the conversion efficiency of the photovoltaic panel; α is the temperature coefficient of the photovoltaic panel; T is the actual ambient temperature; T STC is the temperature under standard test conditions.

[0053] Furthermore, the total photovoltaic power generation power is calculated by the following formula:

[0054] P guang =N PV ·P PV (t)

[0055] N PV is the number of photovoltaic panels, P guang is the total photovoltaic power generation power, P PV (t) is the power generation of a single photovoltaic panel at time t.

[0056] In a possible implementation, whether the total photovoltaic power generation and the total wind power generation meet the user load is determined by the following formula:

[0057] ΔP(t)=N WT ·P WT (t)+N PV ·P PV (t)-P load (t)

[0058] Where ΔP(t) is the differential load, P load (t) is the user load;

[0059] When ΔP(t)>0, it means that the total photovoltaic power generation and the total wind power generation are greater than the user load; it means that the wind power and photovoltaic power output at this time have met the user load and there is excess electricity.

[0060] When ΔP(t)<0, it means that the total photovoltaic power generation and the total wind power generation are less than the user load, indicating that the wind power and photovoltaic power output at this time cannot meet the user's energy demand.

[0061] Furthermore, when the total photovoltaic power generation and the total wind power generation are greater than the user load, the state of charge of the energy storage battery is judged, that is, the SOC state of the energy storage battery is evaluated to determine whether the maximum charging energy constraint is reached. Furthermore, the maximum charging energy constraint of the energy storage battery is usually determined by the design of the battery and the data provided by the manufacturer, such as the total energy capacity of the battery and the safety usage restrictions.

[0062] If the maximum charging energy constraint is not exceeded, the energy storage battery is charged;

[0063] If the energy constraint of the energy storage is exceeded, that is, the battery is fully charged, the remaining electricity can be sold to the grid in the form of grid connection, and in the case of islanding, the excess electricity can only be abandoned, that is, a certain amount of wind power and photovoltaic output load is cut off, which is recorded as abandoned wind and photovoltaic power.

[0064] In one possible implementation, when the total photovoltaic power generation and the total wind power generation are less than the user load, the state of charge of the energy storage battery is judged to determine whether the minimum discharge energy constraint is reached. It can be understood that the minimum discharge energy constraint generally refers to the minimum energy level that the battery energy storage system should maintain during the discharge process to ensure stable operation of the system and avoid deep discharge. Similarly, the minimum discharge energy constraint of the energy storage battery is generally determined based on the battery design and data provided by the manufacturer.

[0065] If the minimum discharge energy constraint is not exceeded, the energy storage battery is discharged, and the energy storage battery starts supplying power to meet the supply of the user load;

[0066] If the minimum discharge energy constraint is exceeded, that is, the battery is in an empty state and cannot output electrical energy, in the form of grid connection, electricity can be purchased from the grid to meet the supply of power load. In the case of an island, the missing electricity can only be supplied by a controllable backup power supply and recorded as power shortage.

[0067] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. The protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A power distribution method based on wind, solar and energy storage microgrid, characterized in that: The power allocation method comprises: Obtain wind power basic data and photovoltaic basic data, obtain wind power generation power based on wind power basic data, and obtain photovoltaic power generation power based on photovoltaic basic data; Obtain the user load situation. When the total photovoltaic power generation and the total wind power generation are greater than the user load, the power generation consistent with the user load is called to realize the power supply of the user load, and the remaining power generation is used to charge the energy storage battery, or sell the remaining power to the power grid, or cut off the abandoned wind and photovoltaic power; When the total photovoltaic power generation and the total wind power generation are less than the user load, all the generated power is used to supply power to the user load. In addition, the energy storage battery is discharged, or electricity is purchased from the grid, or a backup power supply is connected to fill the user load gap.

2. A power distribution method based on wind, solar and energy storage microgrid according to claim 1, characterized in that: The basic wind power data include wind energy utilization coefficient, air density, wind rotor swept area, wind speed, wind turbine tip speed ratio and wind turbine blade moment angle. The wind power generation capacity of a single wind turbine is calculated by the following formula: Among them, P m is the output power of the fan; c p is the wind energy utilization coefficient; ρ is the air density; A is the wind rotor swept area; v winds is the wind speed; λ is the fan blade tip speed ratio; β is the fan blade torque angle.

3. A power distribution method based on wind, solar and energy storage microgrid according to claim 2, characterized in that: The total wind power generation power is calculated by the following formula: P feng =N WT ·P m (t) N WT is the number of fans, P feng is the total wind power generation power, P m (t) is the power generation of a single wind turbine at time t.

4. A power distribution method based on wind, solar and energy storage microgrid according to claim 1, characterized in that: The basic photovoltaic data includes the peak power of the photovoltaic panel, the solar radiation correction factor, the conversion efficiency of the photovoltaic panel, the temperature coefficient of the photovoltaic panel, the actual ambient temperature and the temperature under standard test conditions. The power generation of a single photovoltaic panel is calculated by the following formula: P pv =P max *F*η*(1-α*(TT STC ) Among them, P max is the peak power of the photovoltaic panel; F is the solar radiation correction factor; η is the conversion efficiency of the photovoltaic panel; α is the temperature coefficient of the photovoltaic panel; T is the actual ambient temperature; T STC is the temperature under standard test conditions.

5. A power distribution method based on wind, solar and energy storage microgrid according to claim 4, characterized in that: The total photovoltaic power generation power is calculated by the following formula: P guang =N PV ·P PV (t) N PV is the number of photovoltaic panels, P guang is the total photovoltaic power generation power, P PV (t) is the power generation of a single photovoltaic panel at time t.

6. A power distribution method based on a wind-solar-storage microgrid according to any one of claims 1 to 5, characterized in that: The following formula is used to determine whether the total photovoltaic power generation and the total wind power generation meet the user load: ΔP(t)=N WT ·P WT (t)+N PV ·P PV (t)-P load (t) Where ΔP(t) is the differential load, P load (t) is the user load; When ΔP(t)>0, it means that the total photovoltaic power generation and the total wind power generation are greater than the user load; When ΔP(t)<0, it means that the total photovoltaic power generation and the total wind power generation are less than the user load.

7. A power distribution method based on wind, solar and energy storage microgrid according to claim 6, characterized in that: When the total photovoltaic power generation and the total wind power generation are greater than the user load, the charge state of the energy storage battery is judged to determine whether the maximum charging energy constraint is reached; If the maximum charging energy constraint is not exceeded, the energy storage battery is charged; If the energy limit of the energy storage is exceeded, the remaining electricity will be sold to the grid in the form of grid connection; Eliminate abandoned wind and solar power in isolated island situations.

8. A power distribution method based on wind, solar and energy storage microgrid according to claim 7, characterized in that: When the total photovoltaic power generation and the total wind power generation are less than the user load, the charge state of the energy storage battery is judged to determine whether the minimum discharge energy constraint is reached; If the minimum discharge energy constraint is not exceeded, the energy storage battery is discharged, and the energy storage battery is added to meet the supply of the user load; If the minimum discharge energy constraint is exceeded, electricity will be purchased from the grid to meet the supply of the user's load in the grid-connected form.

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