New energy comprehensive energy supply system micro-grid control and scheduling method

Abstract

The invention relates to a new energy comprehensive energy supply system micro-grid control and scheduling method, and belongs to the field of power systems, the method comprises a micro-grid control method and a micro-grid scheduling method, and the micro-grid control method comprises the steps of judging a system operation state; the heat conduction oil requirement is calculated, and an oil side valve and equipment are controlled according to the calculation result; calculating a molten salt demand, and notifying a salt side valve and equipment according to a calculation result; the micro-grid scheduling method comprises the following steps: receiving illumination prediction information; predicting the generating capacity of each new energy power supply; judging whether the third-day load capacity is met or not; judging whether the load capacity of the second day is met; judging whether the first-day load capacity is met or not; and outputting the current-day operation scheme. According to the method provided by the invention, the coordinated control of the photo-thermal power station under the grid-connected and off-grid micro-grids in the constant-voltage and sliding-voltage modes and the scheduling of various new energy and loads can be realized.

Description

Technical Field

[0001] The present invention belongs to the field of power systems, and in particular relates to a microgrid control and dispatching method for a new energy integrated energy supply system. Background Art

[0002] At present, there is no consistent and perfect solution in China for the control and dispatching method of the microgrid of the new energy integrated energy supply system with the CSP power station as the main body. The coordinated control scheme of the CSP power station in the prior art: the relationship between the load and the thermal oil flow is obtained according to the historical operation data, and the temperature compensation correction is performed; the relationship between the feedforward load and the molten salt pump frequency is obtained by function fitting; according to these two relationships, the thermal oil pump and the molten salt pump are adjusted to complete the matching. The coordinated control of the CSP power station in the sliding pressure operation heat release mode is realized, so as to meet the AGC control requirements of the power grid.

[0003] However, the existing technology has the following defects: the existing control and scheduling technology of solar thermal power stations cannot realize automatic power generation control under various operating conditions, and the existing control and scheduling technology is only applicable to grid-connected microgrids, or off-grid microgrids including thermal power generation, but cannot be applied to pure new energy off-grid microgrids. Summary of the invention

[0004] In view of the above deficiencies in the prior art, the purpose of the invention is to provide a microgrid control and scheduling method for a new energy integrated energy supply system, which can realize the coordinated control of the constant pressure and sliding pressure modes of the solar thermal power station in the grid-connected and off-grid microgrids, as well as the scheduling of various new energy sources and loads.

[0005] The present invention proposes a microgrid control and dispatching method for a new energy integrated energy supply system, including: a microgrid control method and a microgrid dispatching method, wherein:

[0006] The microgrid control method comprises the following steps:

[0007] S11, judging the system operation status;

[0008] S12, calculating the demand for heat transfer oil and controlling the oil-side valves and equipment according to the calculation results;

[0009] S13, calculating the molten salt demand and notifying the salt side valves and equipment according to the calculation results;

[0010] The microgrid dispatching method comprises the following steps:

[0011] S21, receiving illumination prediction information;

[0012] S22, predict the power generation of each new energy source and calculate the existing thermal salt storage heat;

[0013] S23, determining whether the load of the third day is met, if yes, executing step S24, otherwise, transferring the difference to the previous day, and then executing step S24;

[0014] S24, determining whether the load of the next day is met, if yes, executing step S25, otherwise, transferring the difference to the previous day, and then executing step S25;

[0015] S25, determining whether the load of the first day is met, if yes, executing step S26, otherwise reducing the load and taking energy replenishment measures, and returning to step S23;

[0016] S26, output the operation plan for the day.

[0017] Furthermore, in S11, the key valve status and equipment status are obtained, and the system operation mode is determined based on the obtained status information.

[0018] Further, in S12, the thermal oil demand is calculated according to the power generation demand, as shown in the following formula:

[0019]

[0020] Where F is the SGS heat transfer oil flow rate; P is the power generation command; η is the thermoelectric efficiency; h HTFi h is the enthalpy of the heat transfer oil at the SGS inlet; HTFo is the enthalpy of the heat transfer oil at the SGS outlet; η SGS For SGS efficiency.

[0021] Furthermore, in S13, the molten salt demand is further calculated according to the heat transfer oil demand calculated in step S12, as shown in the following formula:

[0022]

[0023] Among them, F salts is the molten salt flow demand; F HTF is the heat transfer oil flow rate; C HTF is the specific heat capacity of the heat transfer oil; C salts is the specific heat capacity of molten salt; T1 is the inlet temperature of heat transfer oil; T2 is the outlet temperature of heat transfer oil; T3 is the hot molten salt temperature; T4 is the cold molten salt temperature.

[0024] Furthermore, in S21 and S22, weather conditions for three consecutive days are obtained, sunlight forecast information is obtained based on the weather conditions, and the power generation of each new energy power source is predicted.

[0025] Furthermore, in S22, the existing hot salt heat storage capacity is further calculated.

[0026] Furthermore, based on the predicted power generation and the existing hot salt heat storage capacity, it is determined whether the load side demand is met.

[0027] Furthermore, the microgrid control method and the microgrid scheduling method are both used to achieve control of a grid-connected microgrid and an off-grid microgrid.

[0028] Furthermore, the microgrid control method is used to achieve coordinated control of the constant pressure and sliding pressure modes of the solar thermal power station in the grid-connected microgrid and the off-grid microgrid.

[0029] Furthermore, in S25, the energy replenishment measures include: a diesel generator connected to a local power grid.

[0030] The beneficial effects of the present invention are as follows:

[0031] (1) The present invention is applicable to automatic power generation control under various operating conditions, and realizes the control of oil-side valves, salt-side valves and equipment.

[0032] (2) The control method provided by the present invention is suitable for realizing coordinated control of a solar thermal power station in a constant pressure or sliding pressure mode in a grid-connected or off-grid microgrid.

[0033] (3) The control method provided by the present invention is applicable to the dispatching of various new energy sources and loads of solar thermal power stations in existing grid-connected and off-grid microgrids. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings are only used to illustrate specific embodiments and are not considered to limit the present invention. In the entire drawings, the same reference symbols represent the same components. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0035] Figure 1 is a flow chart of a control method according to an embodiment of the present invention;

[0036] Figure 2 The figure is a flowchart of a scheduling method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work should fall within the scope of protection of the present invention.

[0038] Furthermore, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts disclosed in the present invention.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the orientation or position relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. The terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0040] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of methods and systems consistent with some aspects of the present invention as detailed in the appended claims.

[0041] The present invention proposes a microgrid control and dispatching method for a new energy comprehensive energy supply system with a solar thermal power station as the main body, including: a microgrid control method and a microgrid dispatching method.

[0042] The following are references Figure 1 and Figure 2 The microgrid control method and the microgrid dispatching method are explained separately.

[0043] like Figure 1 As shown, the microgrid control method includes the following steps:

[0044] S11, judging the system operation status.

[0045] In this step, the key valve status and equipment status are obtained, and the system operation mode is determined based on the obtained status information.

[0046] For example, there is a passage for the heat transfer oil from SF to SGS and TES, that is, the relevant pipelines and valves are open, the relevant equipment is turned on, and the system recognizes it as SF with SGS and TES operation mode.

[0047] S12, calculates the demand for heat transfer oil and controls the oil-side valves and equipment according to the calculation results.

[0048] Specifically, the thermal oil demand is calculated according to the power generation demand, and then the oil side valves and equipment are controlled according to the thermal oil demand instruction.

[0049] In this step, the thermal oil demand is calculated based on the power generation demand, as follows:

[0050]

[0051] Where F is the SGS heat transfer oil flow rate; P is the power generation command; η is the thermoelectric efficiency; h HTFi h is the enthalpy of the heat transfer oil at the SGS inlet; HTFo is the enthalpy of the heat transfer oil at the SGS outlet; η SGS For SGS efficiency.

[0052] S13, calculate the molten salt demand and notify the salt side valves and equipment according to the calculation results.

[0053] Specifically, the molten salt demand is further calculated based on the calculated heat transfer oil demand, and then the molten salt side valves and equipment are controlled based on the molten salt demand.

[0054] In this step, the molten salt demand is calculated as follows:

[0055]

[0056] Among them, F salts is the molten salt flow demand; F HTF is the heat transfer oil flow rate; C HTF is the specific heat capacity of the heat transfer oil; C salts is the specific heat capacity of molten salt; T1 is the inlet temperature of heat transfer oil; T2 is the outlet temperature of heat transfer oil; T3 is the hot molten salt temperature; T4 is the cold molten salt temperature.

[0057] like Figure 2 As shown, the microgrid dispatching method includes the following steps:

[0058] S21, receiving illumination prediction information.

[0059] S22, predict the power generation of each new energy source and calculate the existing hot salt storage heat capacity.

[0060] It should be noted that in steps S21 and S22, weather conditions for three consecutive days are obtained, sunlight forecast information is obtained based on the weather conditions, and the power generation of each new energy power source is predicted.

[0061] In addition, in this step, the existing hot salt heat storage capacity is further calculated. According to the predicted power generation and the existing hot salt heat storage capacity, it is determined whether the load side demand is met.

[0062] S23, determining whether the load of the third day is met, if yes, executing step S24, otherwise, transferring the difference to the previous day, and then executing step S24;

[0063] S24, determining whether the load of the next day is met, if yes, executing step S25, otherwise, transferring the difference to the previous day, and then executing step S25;

[0064] S25, determining whether the load of the first day is met, if yes, executing step S26, otherwise reducing the load and taking energy replenishment measures, and returning to step S23;

[0065] In an embodiment of the present invention, energy replenishment measures include: diesel generators, access to local power grids, etc.

[0066] S26, output the operation plan for the day.

[0067] In summary, the scheduling method obtains weather conditions for three consecutive days, calculates the predicted power generation of each power source and the existing hot salt heat storage capacity; determines whether the power generation on the third day meets the energy supply demand on the third day; if so, determines the situation on the second day; if not, transfers the energy deficit to the previous day and determines the situation on the second day; repeats the above judgment and cycle for the second and first days; and finally outputs the scheduling plan.

[0068] In the present invention, both the microgrid control method and the microgrid dispatching method are used to realize the control of the grid-connected microgrid and the off-grid microgrid.

[0069] Specifically, the microgrid control method is used to achieve coordinated control of the constant pressure and sliding pressure modes of the CSP power station in the grid-connected microgrid and the off-grid microgrid. The microgrid dispatching method is applicable to the grid-connected and off-grid microgrids. According to the weather conditions for three consecutive days, the new energy supply system and energy consumption system with the CSP power station as the main body are reasonably dispatched.

[0070] The control method and scheduling method provided by the present invention can be applied to the field of microgrid control and scheduling of power systems, including but not limited to off-grid solar thermal power stations, grid-connected solar thermal power stations, and the control and scheduling of various new energy power stations including solar thermal power stations.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. Any changes or replacements that can be easily thought of by those skilled in the art within the technical scope disclosed in the present invention should be covered within the protection scope of the present invention.

Claims

1. A microgrid control and dispatching method for a new energy integrated energy supply system, characterized in that: include: A microgrid control method and a microgrid dispatching method, wherein: The microgrid control method comprises the following steps: S11, judging the system operation status; S12, calculating the demand for heat transfer oil and controlling the oil-side valves and equipment according to the calculation results; S13, calculating the molten salt demand and notifying the salt side valves and equipment according to the calculation results; The microgrid dispatching method comprises the following steps: S21, receiving illumination prediction information; S22, predict the power generation of each new energy source and calculate the existing thermal salt storage heat; S23, determining whether the load of the third day is met, if yes, executing step S24, otherwise, transferring the difference to the previous day, and then executing step S24; S24, determine whether the load of the next day is met, if yes, execute step S25, otherwise, transfer the difference to the previous day, and then execute step S25; S25, determining whether the load of the first day is met, if yes, executing step S26, otherwise reducing the load and taking energy replenishment measures, and returning to step S23; S26, output the operation plan for the day.

2. A microgrid control and dispatching method for a new energy integrated energy supply system according to claim 1, characterized in that: In S11, the key valve status and equipment status are obtained, and the system operation mode is determined based on the obtained status information.

3. A microgrid control and dispatching method for a new energy integrated energy supply system according to claim 1, characterized in that: In S12, the thermal oil demand is calculated according to the power generation demand, as shown in the following formula: Where F is the SGS heat transfer oil flow rate; P is the power generation command; η is the thermoelectric efficiency; h HTFi h is the enthalpy of the heat transfer oil at the SGS inlet; HTFo is the enthalpy of the heat transfer oil at the SGS outlet; η SGS For SGS efficiency.

4. A microgrid control and dispatching method for a new energy integrated energy supply system according to claim 1, characterized in that: In S13, the molten salt demand is further calculated according to the heat transfer oil demand calculated in step S12, as shown in the following formula: Among them, F salts is the molten salt flow demand; F HTF is the heat transfer oil flow rate; C HTF is the specific heat capacity of the heat transfer oil; C salts is the specific heat capacity of molten salt; T1 is the inlet temperature of heat transfer oil; T2 is the outlet temperature of heat transfer oil; T3 is the hot molten salt temperature; T4 is the cold molten salt temperature.

5. A new energy integrated energy supply system microgrid control and dispatching method according to claim 1, characterized in that: In S21 and S22, the weather conditions for three consecutive days are obtained, the sunlight forecast information is obtained according to the weather conditions, and the power generation of each new energy power source is predicted.

6. A microgrid control and dispatching method for a new energy integrated energy supply system according to claim 1, characterized in that: In S22, the existing hot salt heat storage capacity is further calculated.

7. A microgrid control and dispatching method for a new energy integrated energy supply system according to claim 6, characterized in that: Based on the predicted power generation and the existing hot salt heat storage capacity, determine whether the load side demand is met.

8. A new energy integrated energy supply system microgrid control and dispatching method according to claim 1, characterized in that: The microgrid control method and the microgrid dispatching method are both used to realize the control of a grid-connected microgrid and an off-grid microgrid.

9. A microgrid control and dispatching method for a new energy integrated energy supply system according to claim 8, characterized in that: The microgrid control method is used to achieve coordinated control of a solar thermal power station in a constant pressure and sliding pressure mode in a grid-connected microgrid and an off-grid microgrid.

10. A microgrid control and dispatching method for a new energy integrated energy supply system according to claim 1, characterized in that: In S25, the energy replenishment measures include: a diesel generator connected to a local power grid.

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