Machine-furnace coordination system and method suitable for photo-thermal power station under isolated network
By introducing a coordinated control level, a basic control level, and a unit level system design into the solar thermal power plant, the problem of difficult coordination between the boiler and turbine in an isolated grid environment is solved, and the energy balance and power quality stability of the solar thermal power plant are achieved. This method is applicable to solar thermal power plants in both isolated and grid-connected environments.
Patent Information
- Application Number
- CN202511312436.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-15
- Publication Date
- 2025-11-11
AI Technical Summary
Existing boiler-turbine coordination systems are not suitable for solar thermal power plants, especially in isolated grid environments where it is difficult to achieve load control and stable power quality, resulting in difficulties in boiler-turbine coordination and instability of isolated grid systems.
A coordinating system for the boiler and turbine of a solar thermal power plant adapted to an isolated grid is designed, comprising a coordination control level, a basic control level, and a unit level. Through the coordinated control of the isolated grid integrated energy management and control center, the main controller of the solar thermal power plant's boiler and turbine, the main controller of the power supply, the boiler control system, and the turbine control system, combined with real-time meteorological conditions and load commands, the system achieves automatic adjustment of the main steam pressure and energy balance.
In an isolated grid environment, the coordinated control of the generator and boiler of the solar thermal power plant was realized, ensuring the energy balance and stable power quality of the system. It can automatically respond to external dispatching needs without manual intervention, filling the gap in existing technology.
Smart Images
Figure CN120926618A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of boiler-turbine coordination technology, and particularly relates to a boiler-turbine coordination system and method adapted to solar thermal power plants under isolated grid conditions. Background Technology
[0002] Existing boiler-turbine coordination systems are all based on traditional thermal power plant systems. Their main function is to receive load commands from the power grid's AGC (Automatic Generation Control) system, control the operation of the boiler and turbine generator, maintain energy balance between them, and keep the main steam pressure stable. By coordinating various sub-loops such as coal quantity, air supply, feedwater, and steam temperature, they maintain the main parameters of the boiler and turbine within a reasonable range while responding to power changes. On the turbine side, the main control object is the valve opening, while on the boiler side, it is the fuel quantity, air volume, and feedwater volume. Therefore, the load can be increased or decreased by adjusting the coal quantity, air volume, and feedwater volume. Solar thermal power plants differ from thermal power plants; they do not have boilers. Instead, they use a solar collector and thermal storage system as heat sources instead of a "furnace," referred to as a "thermal furnace" in this invention. The thermal storage system can adjust the load by increasing or decreasing the flow rate. However, the solar collector differs significantly from traditional thermal power plant boilers, being highly dependent on weather conditions. Load reduction is possible, but load increase is limited by weather. Therefore, there is currently no available technology to achieve boiler-turbine coordination control in solar thermal power plants. The coordinated control of isolated grid boilers and turbines in solar thermal power plants is even more difficult, and there are currently no existing technologies available for application.
[0003] Existing boiler-turbine coordination systems based on thermal power plants have the following problems:
[0004] 1. Not suitable for concentrated solar power (CSP) plants. Due to factors such as weather and system safety protection, CSP plants cannot use existing boiler-turbine coordination control strategies to achieve load control.
[0005] 2. Not suitable for isolated grid environments. Isolated grid environments have no external power grid support, are highly sensitive to fluctuations on the generation and load sides, and have great difficulty in coordinating multiple sources. Existing technologies cannot guarantee the power quality of isolated grid systems, which can easily lead to instability of the isolated grid system or even a complete power outage.
[0006] 3. It is even less suitable for isolated grid environments based on solar thermal power plants. In this scenario, the boiler-turbine coordination system must consider the coordination and control obstacles caused by factors such as weather in the solar thermal power plant, and also maintain the power quality stability of the isolated grid system. Summary of the Invention
[0007] In view of the shortcomings of the prior art, the purpose of this invention is to provide a boiler-machine coordination system and method adapted to solar thermal power plants under isolated grid conditions. The boiler-machine coordination system and method of this invention are highly adaptable and can be used for boiler-machine coordination control in different types of solar thermal power plants. They can also be used in solar thermal power plants under various external environments such as isolated grid and grid-connected grid.
[0008] In a first aspect, the present invention proposes a coordinating system for a solar thermal power plant under isolated grid conditions, comprising: a coordination control level, a basic control level, and a unit level;
[0009] The coordinated control level includes: the isolated grid integrated energy management and control center, the solar thermal power plant boiler and turbine main controller, and the power supply main controller; the basic control level includes: the boiler control system and the turbine control system; the unit level includes: the main pump, the steam generator, and the turbine.
[0010] The isolated grid integrated energy management and control center is connected to the main controller of the solar thermal power plant's boiler and turbine, and the isolated grid integrated energy management and control center is connected to the main power supply controller;
[0011] The main controller of the solar thermal power plant's boiler is connected to the hot furnace control system, and the main controller of the solar thermal power plant's boiler is connected to the steam turbine control system. The hot furnace control system includes: a main pump control system and a steam generator control system.
[0012] The main pump control system is connected to the main pump, the steam generator control system is connected to the steam generator, and the steam turbine control system is connected to the steam turbine.
[0013] The isolated grid integrated energy management and control center is used to acquire external load commands and send them to the main controllers of the solar thermal power plant's boiler and generator units and the main controller of the power supply.
[0014] The isolated grid integrated energy management and control center is connected to the power supply main controller. The isolated grid integrated energy management and control center is used to respond to the first load command in the isolated grid integrated energy system, excluding the solar thermal power plant.
[0015] The main controller of the solar thermal power plant's boiler and turbine is used to receive the second load command, calculate the main steam pressure setpoint based on the second load command, the current unit output power and the current main steam pressure, and then control the turbine control system and the boiler control system to make the main steam pressure reach the main steam pressure setpoint.
[0016] External load commands include two types.
[0017] The first type of load instruction is a load instruction derived from the islanded grid dispatch instruction, the islanded grid frequency, and the dispatchable power margin of the power supply points under the islanded grid.
[0018] The second type of load command is a load command issued by the operator based on the actual situation;
[0019] Both load commands use real-time meteorological conditions obtained by the solar thermal power plant and predictions of future meteorological conditions as inputs to calculate the current and future expected available power margin of the solar thermal power plant.
[0020] A second aspect of the present invention also proposes a method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid, applied to the system described above, comprising the following four steps:
[0021] Step 1: The isolated grid integrated energy management and control center obtains external load commands and sends them to the main controllers of the solar thermal power plant's boiler and generator units and the main controller of the power supply.
[0022] Step 2: The main controller of the solar thermal power plant receives the second load command and calculates the main steam pressure setpoint based on the second load command and the current unit output power;
[0023] Step 3: The main controller of the solar thermal power plant obtains the main steam pressure value, and uses the current unit output power and main steam pressure value as feedforward input signals to control the turbine control system and the furnace control system to make the main steam pressure value reach the main steam pressure set value.
[0024] Step 4: Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has reached the main steam pressure set value, then the above process ends.
[0025] The main steam pressure setpoint is calculated by the steam generator load controller based on the load and steam pressure curves.
[0026] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0027] Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has not reached the main steam pressure set value;
[0028] Then determine whether the heat collection field has reached its maximum output. If the result is that the heat collection field has not reached its maximum output, repeat steps one to four.
[0029] The criterion for determining whether the heat collection field has reached its maximum output is that the heat collection field has been tracked daily and has reached the maximum designed heat transfer oil flow rate.
[0030] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0031] Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has not reached the main steam pressure set value;
[0032] Then determine whether the heat collection field has reached its maximum output. If the result is that the heat collection field has reached its maximum output;
[0033] Then the thermal storage system will start its heat release mode until the power generation load reaches the load command.
[0034] Furthermore, in the aforementioned method for coordinated control of the turbine and boiler in a solar thermal power plant under isolated grid conditions, the external load commands include two types:
[0035] The first type of load instruction is a load instruction derived from the islanded grid dispatch instruction, the islanded grid frequency, and the dispatchable power margin of the power supply points under the islanded grid.
[0036] The second type of load command is a load command issued by the operator based on the actual situation;
[0037] Both load commands use real-time meteorological conditions obtained by the solar thermal power plant and predictions of future meteorological conditions as inputs to calculate the current and future expected available power margin of the solar thermal power plant.
[0038] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0039] Determine whether the solar thermal power plant meets the dispatching conditions;
[0040] If the judgment result is that the solar thermal power plant does not meet the dispatch conditions, the solar thermal power plant sends a lockout command to the integrated energy management and control center.
[0041] Among them, the conditions for scheduling include at least: having a scheduling power margin.
[0042] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0043] The unit currently receives primary frequency regulation, secondary frequency regulation, and secondary voltage regulation commands from the isolated grid side, and automatically adjusts the frequency and voltage in real time.
[0044] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, which controls the turbine control system and the boiler control system to ensure that the main steam pressure reaches the setpoint, includes:
[0045] The turbine control system regulates the steam intake by adjusting the opening of the main steam valve through the main steam pressure PID regulator.
[0046] The furnace control system regulates the main pump speed and heat transfer oil flow through the main pump pressure PID regulator of the main pump control system, and regulates the opening of the heat transfer oil side valve of the steam generator through the pressure PID regulator of the steam generator control system.
[0047] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0048] When the main steam pressure value is greater than the main steam pressure set value, the turbine control system reduces the opening of the main steam valve and reduces the steam intake. At the same time, the hot furnace control system reduces the main pump speed and reduces the opening of the steam generator inlet valve, reducing the amount of heat transfer oil entering the steam generator.
[0049] When the main steam pressure is less than the set main steam pressure, the turbine control system increases the opening of the main steam valve to increase the steam intake. At the same time, the furnace control system increases the main pump speed and increases the opening of the steam generator inlet valve to increase the amount of heat transfer oil entering the steam generator.
[0050] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0051] If increasing the flow rate of the heat transfer oil fails to increase the load, the heat release of the solar thermal power plant's thermal storage system should be controlled to increase the load.
[0052] The beneficial effects of this invention are as follows:
[0053] 1) It solved the problem of difficult coordination between the boiler and turbine in solar thermal power plants, which prevented the application of existing boiler and turbine coordination systems in thermal power plants to achieve automatic energy balance between the heat source and turbine sides;
[0054] 2) Under the dual challenges of weak power supply, fluctuating power quality, and being based on a solar thermal power plant, this system can still achieve internal energy balance, respond to external grid dispatch and frequency regulation needs, and achieve fully automatic control without operator intervention.
[0055] 3) It not only fills the gap in the current solar thermal power plants where there is no existing boiler-turbine coordination system available, but also verifies the functionality and reliability of the boiler-turbine coordination system in the harsh isolated grid environment. Attached Figure Description
[0056] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. It is obvious that the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings.
[0057] Figure 1 A diagram of a boiler-turbine coordination system for a solar thermal power plant under isolated grid conditions is provided as an embodiment of the present invention.
[0058] Figure 2 This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 1 ;
[0059] Figure 3This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 2 ;
[0060] Figure 4 This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 3 ;
[0061] Figure 5 This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 4 . Detailed Implementation
[0062] 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 with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. It should be understood that these descriptions are merely 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 those skilled in the art without creative effort should fall within the scope of protection of the present invention.
[0063] Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts disclosed in this invention.
[0064] In the description of this invention, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "installed," "connected," and "linked" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0065] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of methods and systems consistent with some aspects of the invention as detailed in the appended claims.
[0066] This invention proposes a boiler-turbine coordination system and method suitable for solar thermal power plants operating under isolated grids. It can be used for boiler-turbine coordination control in different types of solar thermal power plants, and can also be applied to solar thermal power plants under various external environments, including isolated and grid-connected systems. This invention uses a trough-type solar thermal power plant as an example, but it is also applicable to tower-type, dish-type, and linear Fresnel-type solar thermal power plants.
[0067] System Implementation Examples
[0068] Figure 1 This invention provides a diagram of a coordinating system for a solar thermal power plant operating under an isolated grid.
[0069] In a first aspect, the present invention proposes a boiler-turbine coordination system adapted to a solar thermal power plant operating under an isolated grid, combined with... Figure 1 This includes: Coordination and Control Level 11, Basic Control Level 12, and Unit Level 13;
[0070] The coordinated control level 11 includes: the isolated grid integrated energy management control center 101, the solar thermal power plant boiler main controller 102, and the power supply main controller 103; the basic control level 12 includes: the hot furnace control system 104 and the steam turbine control system 105; the unit level 13 includes: the main pump 106, the steam generator 107, and the steam turbine 108.
[0071] The isolated grid integrated energy management and control center 101 is connected to the main controller 102 of the solar thermal power plant's boiler and turbine, and the isolated grid integrated energy management and control center 101 is connected to the main power controller 103;
[0072] The main controller 102 of the solar thermal power plant is connected to the hot furnace control system 104, and the main controller 102 of the solar thermal power plant is connected to the steam turbine control system 105. The hot furnace control system 104 includes: a main pump control system 1001 and a steam generator control system 1002.
[0073] The main pump control system 1001 is connected to the main pump 106, the steam generator control system 1002 is connected to the steam generator 107, and the steam turbine control system 105 is connected to the steam turbine 108.
[0074] The isolated grid integrated energy management and control center 101 is connected to the power supply main controller 103, which is used to respond to the first load command in the isolated grid integrated energy system other than the solar thermal power plant.
[0075] The isolated grid integrated energy management and control center 101 is used to obtain external load commands and send them to the solar thermal power plant boiler and turbine main controller 102 and power supply main controller 103;
[0076] The main controller 102 of the solar thermal power plant is used to receive the second external load command, calculate the main steam pressure setpoint based on the second load command and the current unit output power and the current main steam pressure, and then control the turbine control system 105 and the furnace control system 104 to make the main steam pressure reach the main steam pressure setpoint.
[0077] Specifically, in this embodiment of the invention, the isolated grid integrated energy management control center 101 is connected to the power supply main controller 103. The power supply main controller 103 is used to respond to the first load command W1 in the isolated grid integrated energy system, excluding the solar thermal power plant. The power supply main controller 103 is powered by other power sources besides the solar thermal power plant, which can be one or more of wind power, photovoltaic power, electrochemical energy storage, biomass power generation, etc. The isolated grid integrated energy management control center 101 is used to obtain external load commands. The solar thermal power plant boiler main controller 102 receives the second load command W0 issued by the isolated grid integrated energy management control center 101 and determines the load based on the second load command W0 and the current unit output power W. E The main steam pressure setpoint P0 is calculated, and the main steam pressure value P is obtained by the main controller 102 of the solar thermal power plant. T With the current unit output power W E and main steam pressure value P T As feedforward input signals, the turbine control system 105 and the boiler control system 104 are controlled to bring the main steam pressure to the main steam pressure setpoint P0. The external load commands include two types: the first type is a load command converted from the isolated grid dispatch command and the isolated grid frequency, combined with the dispatchable power margin of the power supply points under the isolated grid; the second type is a load command issued by the operator based on the actual situation. Both types of load commands use the real-time acquisition of current meteorological conditions and prediction of future meteorological conditions by the solar thermal power plant as input to calculate the current and future expected available power margin of the solar thermal power plant.
[0078] Method Implementation Examples
[0079] Figure 2 This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 1 .
[0080] A second aspect of the invention also proposes a boiler-turbine coordination method adapted to a solar thermal power plant operating under an isolated grid, applied to the system described above, in conjunction with... Figure 2 It includes four steps, S21 to S22:
[0081] S21: The isolated grid integrated energy management and control center obtains load instructions and sends them to the main controllers of the solar thermal power plant's boiler and generator units and the main controller of the power supply.
[0082] S22: The main controller of the solar thermal power plant receives the second load command and calculates the main steam pressure setpoint based on the second load command and the current unit output power.
[0083] S23: The main controller of the solar thermal power plant obtains the main steam pressure value, and uses the current unit output power and main steam pressure value as feedforward input signals to control the turbine control system and the furnace control system to make the main steam pressure value reach the main steam pressure set value.
[0084] S24: Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has reached the main steam pressure set value, then the above process ends.
[0085] The main steam pressure setpoint is calculated by the steam generator load controller based on the load and steam pressure curves.
[0086] Specifically, in this embodiment of the invention, the isolated grid integrated energy management and control center obtains the second load command W0 and sends the second load command W0 to the main controller of the solar thermal power plant's boiler and turbine. The main controller of the solar thermal power plant receives the second load command W0 and, based on the second load command W0 and the current unit output power W... E The main steam pressure setpoint P0 is calculated, and the main steam pressure value P is obtained by the main controller of the solar thermal power plant's boiler and turbine. T With the current unit output power W E and main steam pressure value P T As a feedforward input signal, the turbine control system and the boiler control system are controlled to bring the main steam pressure to the main steam pressure setpoint P0, and the main steam pressure value P is then determined. T Has the main steam pressure setpoint P0 been reached? If the result is the main steam pressure value P... T Once the main steam pressure setpoint P0 is reached, the above process ends.
[0087] Figure 3 This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 2 .
[0088] Furthermore, the above-mentioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid, combined with... Figure 3 It also includes two steps, S31 and S32:
[0089] S31: Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has not reached the main steam pressure set value;
[0090] S32: Determine whether the heat collection field has reached its maximum output. If the result is that the heat collection field has not reached its maximum output, repeat steps S21 to S24.
[0091] The criterion for determining whether the heat collection field has reached its maximum output is that the heat collection field has been tracked daily and has reached the maximum designed heat transfer oil flow rate.
[0092] Specifically, in this embodiment of the invention, the main steam pressure value P is determined. T Has the main steam pressure setpoint P0 been reached? If the result is the main steam pressure value P... T If the main steam pressure setting value P0 is not reached, determine whether the collector field has reached its maximum output. If the result is that the collector field has not reached its maximum output, repeat steps S21 to S24 for a new round of iteration.
[0093] Figure 4 This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 3 .
[0094] Furthermore, the above-mentioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid, combined with... Figure 4 It also includes three steps, S41 to S43:
[0095] S41: Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has not reached the main steam pressure set value;
[0096] S42: Then determine whether the heat collection field has reached its maximum output. If the result is that the heat collection field has reached its maximum output;
[0097] S43: Then the heat storage system will start in heat release mode until the power generation load reaches the load command.
[0098] Specifically, in this embodiment of the invention, when the heat source of the solar thermal power plant cannot fully meet the requirements of the dispatching command, the solar thermal power plant's thermal storage system starts the heat release mode to respond to the needs of the isolated grid dispatching.
[0099] Furthermore, in the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid, the load commands include two types.
[0100] The first type of load instruction is a load instruction derived from the islanded grid dispatch instruction, the islanded grid frequency, and the dispatchable power margin of the islanded grid's subordinate power sources.
[0101] The second type of load command is a load command issued by the operator based on the actual situation;
[0102] Both load commands use real-time meteorological conditions obtained by the solar thermal power plant and predictions of future meteorological conditions as inputs to calculate the current and future expected available power margin of the solar thermal power plant.
[0103] Figure 5This invention provides a method for coordinating the turbine and boiler in a solar thermal power plant operating under an isolated grid. Figure 4 .
[0104] Furthermore, the above-mentioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid, combined with... Figure 5 It also includes two steps, S51 and S52:
[0105] S51: Determine whether the solar thermal power plant meets the dispatching conditions;
[0106] S52: If the judgment result is that the solar thermal power plant does not meet the dispatch conditions, the solar thermal power plant sends a lockout command to the integrated energy management and control center.
[0107] Among them, the conditions for scheduling include at least: having a scheduling power margin.
[0108] Specifically, in this embodiment of the invention, when the solar thermal power plant has no dispatchable power margin or does not meet the dispatching conditions, the solar thermal power plant sends a blocking command to the integrated energy management and control center.
[0109] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0110] The unit currently receives primary frequency regulation, secondary frequency regulation, and secondary voltage regulation commands from the isolated grid side, and automatically adjusts the frequency and voltage in real time.
[0111] Specifically, in this embodiment of the invention, the current unit simultaneously receives primary frequency regulation, secondary frequency regulation, and secondary voltage regulation commands from the islanded grid side, and automatically regulates frequency and voltage in real time to maintain the stability of the grid frequency and bus voltage.
[0112] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, which controls the turbine control system and the boiler control system to ensure that the main steam pressure reaches the setpoint, includes:
[0113] The turbine control system regulates the steam intake by adjusting the opening of the main steam valve through the main steam pressure PID regulator.
[0114] The furnace control system regulates the main pump speed and heat transfer oil flow through the main pump pressure PID regulator of the main pump control system, and regulates the opening of the heat transfer oil side valve of the steam generator through the pressure PID regulator of the steam generator control system.
[0115] Specifically, in this embodiment of the invention, the turbine control system regulates the steam flow rate by adjusting the main steam valve opening through the main steam pressure PID regulator; the boiler control system regulates the heat transfer oil flow rate by adjusting the main pump speed through the main pump pressure PID regulator of the main pump control system; and the heat transfer oil side valve opening is adjusted through the pressure PID regulator of the steam generator control system to ultimately achieve the main steam pressure value P. TThe main steam pressure setpoint P0 has been reached.
[0116] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0117] When the main steam pressure value is greater than the main steam pressure set value, the turbine control system reduces the opening of the main steam valve and reduces the steam intake. At the same time, the hot furnace control system reduces the main pump speed and reduces the opening of the steam generator inlet valve, reducing the amount of heat transfer oil entering the steam generator.
[0118] When the main steam pressure is less than the set main steam pressure, the turbine control system increases the opening of the main steam valve to increase the steam intake. At the same time, the furnace control system increases the main pump speed and increases the opening of the steam generator inlet valve to increase the amount of heat transfer oil entering the steam generator.
[0119] Specifically, in this embodiment of the invention, when the main steam pressure value P T When the main steam pressure exceeds the set value P0, the unit is deemed to need to reduce load. The turbine control system reduces the opening of the main steam valve, decreasing the steam flow. Simultaneously, the boiler control system reduces the main pump speed and decreases the opening of the steam generator inlet valve, reducing the amount of heat transfer oil entering the steam generator. When the main steam pressure value P... T When the main steam pressure is less than the set value P0, it is determined that the unit needs to increase the load. The turbine control system increases the opening of the main steam valve to increase the steam intake. At the same time, the hot furnace control system increases the speed of the main pump and increases the opening of the steam generator inlet valve to increase the amount of heat transfer oil entering the steam generator.
[0120] Furthermore, the aforementioned method for coordinating the turbine and boiler in a solar thermal power plant under an isolated grid also includes:
[0121] If increasing the flow rate of the heat transfer oil fails to increase the load, the heat release of the solar thermal power plant's thermal storage system should be controlled to increase the load.
[0122] Specifically, in this embodiment of the invention, if the load cannot be increased by continuing to increase the flow rate of the heat transfer oil, the solar thermal power plant's thermal storage system will start the heat release mode to respond to the needs of isolated grid dispatch.
[0123] Those skilled in the art will understand that although some embodiments described herein include certain features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of the invention and form different embodiments.
[0124] Those skilled in the art will understand that the descriptions of the various embodiments have different focuses, and for parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0125] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention. All such modifications and variations fall within the scope defined by the appended claims. The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
[0126] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.
Claims
1. A boiler-turbine coordination system adapted to a solar thermal power plant under isolated grid conditions, characterized in that, include: Coordination control level, basic control level, and unit level; The coordinated control level includes: an isolated grid integrated energy management and control center, a solar thermal power plant boiler and turbine main controller, and a power supply main controller; the basic control level includes: a boiler control system and a turbine control system; the unit level includes: a main pump, a steam generator, and a turbine. The isolated grid integrated energy management and control center is connected to the main controller of the solar thermal power plant's boiler and turbine, and the isolated grid integrated energy management and control center is connected to the main power controller; The main controller of the solar thermal power plant's boiler is connected to the furnace control system, and the main controller of the solar thermal power plant's boiler is connected to the turbine control system. The furnace control system includes: a main pump control system and a steam generator control system. The main pump control system is connected to the main pump, the steam generator control system is connected to the steam generator, and the steam turbine control system is connected to the steam turbine. The isolated grid integrated energy management and control center is used to acquire external load commands and send the external load commands to the main controller of the solar thermal power plant's boiler and the main controller of the power supply. The isolated grid integrated energy management and control center is connected to the power supply main controller, which is used to respond to the first load command in the isolated grid integrated energy system, excluding the solar thermal power plant. The main controller of the solar thermal power plant is used to receive the second load command, calculate the main steam pressure setpoint based on the second load command, the current unit output power and the current main steam pressure, and then control the turbine control system and the furnace control system to make the main steam pressure reach the main steam pressure setpoint. The external load commands include two types. The first type of load instruction is a load instruction derived from the islanded grid dispatch instruction, the islanded grid frequency, and the dispatchable power margin of the power supply points under the islanded grid. The second type of load command is a load command issued by the operator based on the actual situation; Both load commands use real-time meteorological conditions obtained by the solar thermal power plant and predictions of future meteorological conditions as inputs to calculate the current and future expected available power margin of the solar thermal power plant.
2. A method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, applied to the system described in claim 1, characterized in that, It includes the following four steps: Step 1: The isolated grid integrated energy management and control center obtains external load commands and sends the external load commands to the main controller of the solar thermal power plant's boiler and generator and the main controller of the power supply. Step 2: The main controller of the solar thermal power plant receives the second load command and calculates the main steam pressure setpoint based on the second load command and the current unit output power; Step 3: The main controller of the solar thermal power plant obtains the main steam pressure value, and uses the current unit output power and main steam pressure value as feedforward input signals to control the turbine control system and the furnace control system to make the main steam pressure value reach the main steam pressure set value. Step 4: Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has reached the main steam pressure set value, then the above process ends. The main steam pressure setpoint is calculated by the steam generator load controller based on the load and steam pressure curves.
3. The method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions according to claim 2, characterized in that, The method further includes: Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has not reached the main steam pressure set value; Then determine whether the heat collection field has reached its maximum output. If the result is that the heat collection field has not reached its maximum output, repeat steps one to four. The criterion for determining whether the heat collection field has reached its maximum output is that the heat collection field has been tracked daily and has reached the maximum designed heat transfer oil flow rate.
4. The method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions according to claim 2, characterized in that, The method further includes: Determine whether the main steam pressure value has reached the main steam pressure set value. If the determination result is that the main steam pressure value has not reached the main steam pressure set value; Then determine whether the heat collection field has reached its maximum output. If the determination result is that the heat collection field has reached its maximum output; Then the thermal storage system will start its heat release mode until the power generation load reaches the load command.
5. A method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, as described in claim 2, is characterized in that... The external load commands include two types. The first type of load instruction is a load instruction derived from the islanded grid dispatch instruction, the islanded grid frequency, and the dispatchable power margin of the power supply points under the islanded grid. The second type of load command is a load command issued by the operator based on the actual situation; Both load commands use real-time meteorological conditions obtained by the solar thermal power plant and predictions of future meteorological conditions as inputs to calculate the current and future expected available power margin of the solar thermal power plant.
6. A method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, as described in claim 2, is characterized in that... The method further includes: Determine whether the solar thermal power plant meets the dispatching requirements; If the judgment result is that the solar thermal power plant does not meet the dispatch conditions, the solar thermal power plant sends a lockout command to the integrated energy management and control center. Among them, the conditions for scheduling include at least: having a scheduling power margin.
7. A method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, as described in claim 2, is characterized in that... The method further includes: The unit currently receives primary frequency regulation, secondary frequency regulation, and secondary voltage regulation commands from the isolated grid side, and automatically adjusts frequency and voltage in real time.
8. A method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, as described in claim 2, is characterized in that... Controlling the turbine control system and the furnace control system to ensure the main steam pressure reaches the setpoint includes: The turbine control system regulates the steam intake by adjusting the opening of the main steam valve through the main steam pressure PID regulator. The furnace control system regulates the main pump speed and heat transfer oil flow through the main pump pressure PID regulator of the main pump control system, and regulates the opening of the heat transfer oil side valve of the steam generator through the pressure PID regulator of the steam generator control system.
9. A method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, as described in claim 8, is characterized in that... The method further includes: When the main steam pressure value is greater than the main steam pressure set value, the turbine control system reduces the opening of the main steam valve and reduces the steam intake. At the same time, the hot furnace control system reduces the main pump speed and reduces the opening of the steam generator inlet valve, thereby reducing the amount of heat transfer oil entering the steam generator. When the main steam pressure value is less than the main steam pressure set value, the turbine control system increases the opening of the main steam valve to increase the steam intake. At the same time, the furnace control system increases the main pump speed and increases the opening of the steam generator inlet valve to increase the amount of heat transfer oil entering the steam generator.
10. A method for coordinating the turbine and boiler in a solar thermal power plant under isolated grid conditions, as described in claim 9, is characterized in that... The method further includes: If increasing the flow rate of the heat transfer oil fails to increase the load, control the heat release of the solar thermal power plant's thermal storage system to increase the load.