Photo-thermal power generation control method and system applied to plateau isolated network energy station

Abstract

The invention provides a photo-thermal power generation control method and system applied to a plateau isolated network energy station, and the method comprises the following steps: S1, detecting and judging the separate and parallel states of a photo-thermal power generation unit and an energy storage unit, switching the operation state of the photo-thermal power generation unit to an isolated network mode when the photo-thermal power generation unit and the energy storage unit are in a separate state, and stopping the operation of the photo-thermal power generation unit; when the photo-thermal power generation unit and the energy storage unit are in the parallel state, the operation state of the photo-thermal power generation unit is switched to a grid-connected mode; s2, in the isolated network mode, the photo-thermal power generation unit outputs load electric energy to the independent power grid, and actively executes frequency modulation and voltage regulation operation based on the electrical load condition of the independent power grid; and S3, in the grid-connected mode, the photo-thermal power generation unit outputs load electric energy to the independent power grid and outputs energy storage electric energy to the energy storage unit.

Description

Technical Field

[0001] The present invention belongs to the technical field of power control, and in particular relates to a solar thermal power generation control method and system applied to a plateau isolated grid energy station. Background Art

[0002] A solar thermal power generation unit is a technical device that converts the radiant energy of sunlight into thermal energy, and then further converts it into electrical energy. It involves using optical devices such as reflectors or lenses to focus a large area of ​​sunlight onto a small area, thereby generating high temperatures. The sunlight concentrated in a small area heats a certain heat transfer medium (such as oil, molten salt or water / steam). The heated heat transfer medium generates steam, and the high-pressure steam then drives a turbine to convert thermal energy into mechanical energy. Finally, the turbine drives a generator to convert mechanical energy into electrical energy.

[0003] The Zabuye Salt Lake Lithium Extraction Project is a lithium resource development project located in the Zabuye Salt Lake in Zhongba County, Shigatse City, Tibet Autonomous Region, China. The construction of the Zabuye Salt Lake Lithium Extraction Project aims to utilize the abundant solar energy resources on the plateau and extract lithium in a low-energy, short-cycle and low-cost manner. A plateau isolated grid energy station refers to an independent power supply system operating in a high-altitude area. An independent power grid is constructed inside the plateau isolated grid energy station. A solar thermal power generation unit and an energy storage unit are further provided in the independent power grid. The energy storage unit is used to store the excess electric energy generated by the solar thermal power generation unit. However, under the existing technology, the control method for the solar thermal power generation unit is only applicable to the case where the solar thermal power generation unit and the energy storage unit are normally connected, and the traditional digital electro-hydraulic control system (DEH) is mostly used to realize the operation control of the steam turbine in the solar thermal power generation unit, including starting, stopping and load adjustment in the case of grid connection. When the solar thermal power generation unit and the energy storage unit are disconnected and separated, it is easy to cause the overall power outage of the independent power grid. In addition, due to the long control cycle and low sensitivity of the traditional digital electro-hydraulic control system, it is impossible to achieve efficient and stable regulation of the solar thermal power generation unit in the isolated grid state. Summary of the invention

[0004] The present invention aims to provide a method and system for controlling solar thermal power generation applied to isolated grid energy stations in plateaus, so as to solve the technical problem that, under the prior art, conventional solar thermal power generation units are only provided with a grid-connected mode, and effective regulation cannot be achieved when the solar thermal power generation units are disconnected and separated from the energy storage units.

[0005] In order to solve the above problems, the technical solution of the present invention is: a solar thermal power generation control method applied to a plateau isolated grid energy station, comprising the following steps: S1: Detect and determine the separate and parallel states of the CSP unit and the energy storage unit. When the CSP unit and the energy storage unit are in separate states, switch the operation state of the CSP unit to the isolated grid mode. When the CSP unit and the energy storage unit are in parallel states, switch the operation state of the CSP unit to the grid-connected mode. S2: In the isolated grid mode, the CSP unit outputs load electric energy to the independent grid, and actively performs frequency and voltage regulation based on the power load of the independent grid; S3: In the grid-connected mode, the solar thermal power generation unit outputs load electric energy to the independent power grid and outputs storage electric energy to the energy storage unit.

[0006] Preferably, in S2, in the isolated grid mode, the CSP power generation unit outputs load electric energy to the independent grid, which specifically includes the following steps: S21: when the CSP power generation unit is stopped and waiting to be started, the CSP power generation unit rotates the regulating stage blades of the CSP power generation steam turbine from a stationary state to a rated speed through a steam turbine digital electro-hydraulic control mechanism; S22: The speed of the regulating stage blades of the solar thermal power generation steam turbine is secondarily adjusted through a frequency rapid response mechanism to output load electric energy of corresponding output frequency and output voltage to the independent power grid.

[0007] Preferably, when the solar thermal power generation unit has only one set of first solar thermal power generation electronic devices, the frequency rapid response mechanism includes a single-machine frequency and voltage regulation control mode, specifically including the following steps: S221: measuring real-time frequency data in the independent power grid by a frequency sensor, comparing the real-time frequency data with preset target frequency data, and directly adjusting the output frequency of the first solar thermal power generation electronic device based on the frequency difference between the real-time frequency data and the target frequency data; S222: measuring real-time voltage data in the independent power grid through a voltage transformer, comparing the real-time voltage data with preset target voltage data, and directly adjusting the output voltage of the first solar thermal power generation electronic device based on the voltage difference between the real-time voltage data and the target voltage data.

[0008] Preferably, when the solar thermal power generation unit has a plurality of second solar thermal power generation electronic devices operating in parallel, the frequency rapid response mechanism includes a multi-machine frequency and voltage regulation control mode, specifically including the following steps: S223: measuring real-time frequency data in the independent power grid through a frequency sensor, comparing the real-time frequency data with preset target frequency data, obtaining a frequency demand of the independent power grid based on a frequency difference between the real-time frequency data and the target frequency data, and allocating the frequency demand of the independent power grid to the plurality of second CSP electronic devices in proportion according to different rated capacities of the plurality of second CSP electronic devices; S224: Measure the real-time voltage data in the independent power grid through a voltage transformer, compare the real-time voltage data with the preset target voltage data, obtain the voltage demand of the independent power grid based on the voltage difference between the real-time voltage data and the target voltage data, and distribute the voltage demand of the independent power grid to the plurality of the second solar thermal power generation electronic devices in proportion according to the different maximum reactive powers of the plurality of the second solar thermal power generation electronic devices.

[0009] Preferably, the frequency rapid response mechanism includes a manual frequency modulation and voltage regulation control mode, in which the output frequency and output voltage of the first photothermal electronic device or any of the second photothermal electronic devices are manually and independently controlled; When the first photovoltaic electronic device or any of the second photovoltaic electronic devices fails to automatically adjust the frequency and voltage, the photovoltaic power generation unit outputs an alarm and automatically switches from a single-machine frequency and voltage control mode or a multi-machine frequency and voltage control mode to a manual frequency and voltage control mode.

[0010] Preferably, in the grid-connected mode, the solar thermal power generation unit outputs load electric energy to the independent power grid according to the dispatching instruction output by the dispatching master station, and outputs storage electric energy to the energy storage unit.

[0011] Preferably, in S3, in the grid-connected mode, the CSP unit outputs load electric energy to the independent power grid and outputs stored electric energy to the energy storage unit, which specifically includes the following steps: S31: respectively measuring the real-time frequency data in the independent power grid and the energy storage unit through a frequency sensor, comparing the real-time frequency data with the target frequency data recorded in the dispatch instruction, and adjusting the total output frequency of the CSP unit outputting load electric energy to the independent power grid and outputting stored electric energy to the energy storage unit based on the frequency difference between the real-time frequency data and the target frequency data; S32: Real-time voltage data of the independent power grid and the energy storage unit are measured respectively by voltage transformers, the real-time voltage data are compared with the target voltage data recorded in the dispatch instruction, and based on the voltage difference between the real-time voltage data and the target voltage data, the total output voltage of the solar thermal power generation unit to output load electric energy to the independent power grid and to output storage electric energy to the energy storage unit is adjusted.

[0012] Preferably, the method further comprises the following steps: S4: The solar thermal power generation unit compares the load electric energy output to the independent power grid and the stored electric energy output to the energy storage unit with the maximum limit of the SGS operating boundary respectively. When the active power value and / or reactive power value of the load electric energy or the stored electric energy exceeds the maximum limit of the SGS operating boundary, the maximum limit set by the SGS operating boundary is used as the final output active power value and / or reactive power value.

[0013] Preferably, the CSP unit is provided with a rapid load reduction mechanism. When the CSP unit self-checks and finds a mechanical fault, the CSP unit automatically reduces its output power based on the rapid load reduction mechanism and automatically switches to the isolated grid mode.

[0014] Based on the same concept, the present invention also provides a solar thermal power generation control system applied to a plateau isolated grid energy station, which executes a solar thermal power generation control method applied to a plateau isolated grid energy station as described in any one of the above, including: A photothermal power generation unit, wherein the photothermal power generation unit and the energy storage unit are in a separate or parallel state. When the photothermal power generation unit and the energy storage unit are in a separate state, the photothermal power generation unit is used to output load electric energy to an independent power grid. When the photothermal power generation unit and the energy storage unit are in a parallel state, the photothermal power generation unit is used to output load electric energy to the independent power grid and output storage electric energy to the energy storage unit.

[0015] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art: The present invention provides a method and system for controlling photothermal power generation applied to an isolated grid energy station on a plateau. According to the parallel connection status of the photothermal power generation unit and the energy storage unit, the photothermal power generation unit is provided with an isolated grid mode and a grid-connected grid mode. In the grid-connected grid mode, the photothermal power generation unit can output load electric energy to the independent grid and output storage electric energy to the energy storage unit. When the photothermal power generation unit and the energy storage unit are disconnected or separated due to abnormal connection, the photothermal power generation unit can keep outputting load electric energy to the independent grid and realize frequency and voltage regulation through the frequency management and control system (FMS), so as to effectively maintain the continuous and stable power supply function of the independent grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The present invention provides a flow chart of a solar thermal power generation control method applied to a plateau isolated grid energy station. DETAILED DESCRIPTION

[0017] The following is a further detailed description of a solar thermal power generation control method and system for plateau isolated grid energy stations proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer according to the following description and claims.

[0018] First embodiment See also Figure 1 This embodiment provides a method for controlling CSP power generation applied to a plateau isolated grid energy station, which is used to realize the function of automatically switching the power supply logic of the CSP power generation unit when the CSP power generation unit is in a separate or parallel state with the energy storage unit, and specifically includes the following steps: S1: The CSP unit detects and determines its parallel state with the energy storage unit. When the CSP unit and the energy storage unit are in a separate state, the operation state of the CSP unit is switched to the isolated grid mode. When the CSP unit and the energy storage unit are in a parallel state, the operation state of the CSP unit is switched to the grid-connected mode.

[0019] S2: In the isolated grid mode, the CSP unit continues to output load power to the independent grid to maintain the operation of basic power equipment, and actively performs frequency and voltage regulation operations based on the power load of the independent grid to ensure the stability of the power supply of the independent grid.

[0020] S3: In the grid-connected mode, the CSP unit outputs load power to the independent grid to maintain the operation of all power equipment, and outputs storage power to the energy storage unit to realize the power supply of the independent grid and the charging function of the energy storage unit.

[0021] In this embodiment, the solar thermal power generation unit is a power generation unit located in the plateau isolated grid energy station, which is used to provide electric energy for the independent power grid constructed by the plateau isolated grid energy station and the energy storage unit arranged in the plateau isolated grid energy station. When the solar thermal power generation unit and the energy storage unit are in a separate state, it means that the solar thermal power generation unit and the energy storage unit may be disconnected due to a fault. Since the solar thermal power generation unit also directly provides electric energy to the independent grid, in order to prevent the large electric energy (load electric energy and energy storage electric energy) output by the solar thermal power generation unit from impacting the independent grid, under the existing technology, the solar thermal power generation unit is usually actively disconnected from the independent grid, which results in a lack of power supply inside the independent grid and a power outage. In this embodiment, when the CSP unit and the energy storage unit are in a separate state, the operation state of the CSP unit can be automatically switched to the isolated grid mode. In the isolated grid mode, the CSP unit can still maintain the basic power supply of the independent grid at a lower power to prevent the independent grid from power failure. When the CSP unit and the energy storage unit are in a parallel state, the operation state of the CSP unit can be automatically switched to the grid-connected mode, thereby supplying power to the independent grid and the energy storage unit respectively. Through the flexible and autonomous switching of the CSP unit between the isolated grid mode and the grid-connected mode, the power supply object and power supply strategy of the CSP unit can be dynamically adjusted to effectively guarantee the power demand and power supply safety and stability of the independent grid.

[0022] The specific implementation steps and functions of a solar thermal power generation control method for a plateau isolated grid energy station provided in this embodiment will be further described in detail below: Preferably, in this embodiment, in S2, in the isolated grid mode, the CSP power generation unit outputs load electric energy to the independent grid, which specifically includes the following steps: S21: When the CSP unit is disconnected from the energy storage unit, the CSP unit is briefly shut down and restarted. Then, during the shutdown and waiting process of the CSP unit, the CSP unit first rotates the regulating stage blades of the CSP steam turbine from a stationary state to a rated speed through the steam turbine digital electro-hydraulic control mechanism (DEH, Digital Electro-Hydraulic Control System); S22: When the regulating stage blades of the CSP steam turbine of the CSP unit reach the rated speed, the speed of the regulating stage blades of the CSP steam turbine is secondarily adjusted through the frequency fast response mechanism (FMS, Frequency Management System), thereby outputting the load power of the corresponding output frequency and output voltage to the independent power grid.

[0023] Therefore, in this embodiment, the startup of the CSP unit is firstly realized with the help of the traditional digital electro-hydraulic control mechanism of the steam turbine, and then the frequency rapid response mechanism can be used to realize the secondary precise adjustment of the energy output of the CSP unit, and the frequency rapid response mechanism is used to enhance the response capability of the CSP unit to the changes of the independent power grid load.

[0024] Specifically, in this embodiment, a photovoltaic power generation electronic device is provided in the photovoltaic power generation unit, and the photovoltaic power generation electronic device includes, for example, a trough photovoltaic power generation device and a tower photovoltaic power generation device. When there is only one set of first photovoltaic power generation electronic devices in the photovoltaic power generation unit, the frequency rapid response mechanism includes a single-machine frequency and voltage regulation control mode for a single first photovoltaic power generation electronic device, specifically including the following steps: S221: The solar thermal power generation unit measures the real-time frequency data in the independent power grid through a frequency sensor, compares the real-time frequency data with the preset target frequency data, and directly adjusts the output frequency of the first solar thermal power generation electronic device based on the frequency difference between the real-time frequency data and the target frequency data, that is, adjusts the active power output of the first solar thermal power generation electronic device; S222: The solar thermal power generation unit measures the real-time voltage data in the independent power grid through a voltage transformer, compares the real-time voltage data with the preset target voltage data, and directly adjusts the output voltage of the first solar thermal power generation electronic device based on the voltage difference between the real-time voltage data and the target voltage data, that is, adjusts the reactive power output of the first solar thermal power generation electronic device.

[0025] In this embodiment, a single-machine solar thermal power generation unit in an isolated grid state autonomously utilizes real-time monitoring and adjustment of the output frequency to match the actual frequency demand of the independent grid based on the single-machine frequency and voltage regulation control mode under the frequency rapid response mechanism, effectively maintaining the frequency of the independent grid within the target range, and real-time monitoring and adjustment of the output voltage can avoid damage to load equipment in the independent grid caused by excessively high or low voltage, thereby ensuring the stability of the independent grid voltage. At the same time, compared with relying on the digital electro-hydraulic control mechanism of the steam turbine, the inherent delay and adjustment step of the frequency rapid response mechanism are shorter, and it has better response speed and regulation accuracy.

[0026] Furthermore, in this embodiment, when there are a plurality of second photovoltaic electronic devices operating in parallel in the photovoltaic power generation unit, that is, a plurality of groups of second photovoltaic electronic devices operate synchronously and jointly supply electric energy to the independent power grid, the frequency rapid response mechanism is adjusted to a multi-machine frequency and voltage regulation control mode, which specifically includes the following steps: S223: measuring real-time frequency data in the independent power grid through a frequency sensor, comparing the real-time frequency data with preset target frequency data, obtaining a frequency demand of the independent power grid based on a frequency difference between the real-time frequency data and the target frequency data, and allocating the frequency demand of the independent power grid to the plurality of second solar thermal power generation electronic devices in proportion according to different rated capacities of the plurality of second solar thermal power generation electronic devices; Specifically, the real-time frequency data is compared with the preset target frequency data, and the frequency difference between the real-time frequency data and the target frequency data is calculated. f target is the target frequency, f real is the real-time frequency.

[0027] Frequency demand is usually achieved by adjusting the active power output. If the frequency difference is positive, it proves that the CSP unit needs to increase the active power output. If the frequency difference is negative, it proves that the CSP unit needs to reduce the active power output.

[0028] The frequency demand can be used to calculate the specific active power adjustment through the droop control formula, that is, R is the droop coefficient and P0 is the rated active power.

[0029] According to the different rated capacities of the second CSP electronic devices, the frequency demand is proportionally distributed to each second CSP electronic device. If the total frequency demand is , then the frequency demand allocation amount P of each second photothermal power generation electronic device i i That is S224: Measure the real-time voltage data in the independent power grid through a voltage transformer, compare the real-time voltage data with the preset target voltage data, obtain the voltage demand of the independent power grid based on the voltage difference between the real-time voltage data and the target voltage data, and distribute the voltage demand of the independent power grid to the plurality of second solar thermal power generation electronic devices in proportion according to the different maximum reactive powers of the plurality of second solar thermal power generation electronic devices.

[0030] Specifically, the measured real-time voltage data is compared with the preset target voltage data, and the voltage difference between the two is calculated, that is, V target is the target frequency, V real is the real-time frequency.

[0031] Voltage demand is usually achieved by adjusting reactive power output. If the voltage difference is positive, it proves that the CSP unit needs to increase reactive power output. If the voltage difference is negative, it proves that the CSP unit needs to reduce reactive power output.

[0032] The reactive power demand can be estimated by the following formula: Q is the reactive power demand, V is the voltage, I is the current, and sin(ϕ) is the sine of the power factor angle.

[0033] According to the different maximum reactive power capabilities of several second CSP electronic devices, the voltage demand is proportionally distributed to each second CSP electronic device. If the total voltage demand is , then the voltage demand allocation amount Q of each second photothermal power generation electronic device i is i That is In this embodiment, the multi-machine CSP power generation units in the isolated grid state are based on the multi-machine frequency and voltage regulation control mode under the frequency rapid response mechanism, and utilize real-time monitoring and adjustment of the output frequency to match the actual frequency demand of the independent grid, effectively maintaining the frequency of the independent grid within the target range, and real-time monitoring and adjustment of the output voltage can avoid damage to load equipment in the independent grid caused by excessively high or low voltage, thereby ensuring the stability of the independent grid voltage. At the same time, compared with the digital electro-hydraulic control mechanism that relies on the steam turbine, the inherent delay and adjustment step of the frequency rapid response mechanism are shorter, with better response speed and regulation accuracy, and the resources of the multi-machine CSP power generation units can be fully, flexibly and reasonably dispatched and allocated, thereby improving the overall performance of the system.

[0034] Preferably, in this embodiment, the frequency rapid response mechanism also includes a manual frequency modulation and voltage regulation control mode, in which the output frequency and output voltage of the first photothermal electronic device or any second photothermal electronic device can be manually and independently controlled; When the first solar thermal power generation electronic device or any second solar thermal power generation electronic device has an automatic frequency and voltage regulation failure, the solar thermal power generation unit outputs an alarm and automatically switches from a single-machine frequency and voltage regulation control mode or a multi-machine frequency and voltage regulation control mode to a manual frequency and voltage regulation control mode.

[0035] In this embodiment, the manual frequency and voltage regulation control mode provides a backup plan for the control system. When the automatic frequency and voltage regulation of the control system fails or fails, the operator can continue to make necessary adjustments through the manual mode to ensure the stability of the power grid and the safe operation of the equipment, and can manually control the output frequency and output voltage of the first photothermal electronic device or any second photothermal electronic device to achieve personalized and flexible adjustment of the photothermal electronic device.

[0036] Preferably, in this embodiment, in the grid-connected mode, the solar thermal power generation unit outputs load electric energy to the independent power grid according to the dispatching instructions output by the dispatching master station, and outputs storage electric energy to the energy storage unit. The dispatching master station can dynamically adjust the output power of the solar thermal power generation unit according to the needs of the entire independent power grid, ensure the stability of the frequency and voltage of the independent power grid, and realize the remote automatic monitoring and control function of the solar thermal power generation unit.

[0037] Furthermore, in S3, in the grid-connected mode, the CSP unit outputs load electric energy to the independent power grid and outputs stored electric energy to the energy storage unit, which specifically includes the following steps: S31: measuring the real-time frequency data in the independent power grid and the energy storage unit respectively through the frequency sensor, comparing the real-time frequency data with the target frequency data recorded in the dispatch instruction, and adjusting the output frequency of the CSP unit to output load power to the independent power grid and output storage power to the energy storage unit based on the frequency difference between the real-time frequency data and the target frequency data; S32: Real-time voltage data in the independent power grid and the energy storage unit are measured respectively through voltage transformers, the real-time voltage data are compared with the target voltage data recorded in the dispatch instruction, and based on the voltage difference between the real-time voltage data and the target voltage data, the output voltage of the solar thermal power generation unit to output load electric energy to the independent power grid and the output voltage of the stored electric energy to the energy storage unit are adjusted respectively.

[0038] Among them, the specific steps of adjusting the output frequency and output voltage of the solar thermal power generation unit to the independent power grid or energy storage unit in S31 and S32 can be referred to S221-S224. It is worth noting that in this embodiment, the priority of the solar thermal power generation unit in supplying power to the independent power grid is higher than that of the energy storage unit. The dispatching master station can monitor the status of the independent power grid and the energy storage unit (including frequency, voltage, load, etc.) in real time, and plan the output of the solar thermal power generation unit in advance in combination with weather forecast, load forecast and other information to ensure that it gives priority to meeting the power supply needs of the independent power grid. When the power supply needs of the independent power grid are met, if there is surplus power, the excess power can be stored in the energy storage unit.

[0039] Preferably, in this embodiment, the following steps are also included: S4: The CSP unit compares the load power output to the independent power grid and the storage power output to the energy storage unit with the maximum limit of the SGS operation boundary. When the active power value and / or reactive power value of the load power or storage power exceeds the maximum limit of the SGS operation boundary, the maximum limit set by the SGS operation boundary shall be used as the final output active power value and / or reactive power value.

[0040] Specifically, the SGS operating boundary refers to the limit parameter range within which the CSP unit or each component in the entire power system can operate safely and stably, and these parameters usually include active power (P), reactive power (Q), voltage (V), current (I), etc. Through the above steps, it can be ensured that the CSP unit will not exceed the limit of its SGS operating boundary while meeting the needs of the independent power grid and energy storage unit, which not only ensures the safety of the system, but also effectively avoids equipment damage or other potential problems caused by overload.

[0041] Preferably, in the present embodiment, the CSP unit is provided with a fast load reduction mechanism (FCB, Fast CutBack). When the CSP unit self-checks and finds a mechanical fault, such as abnormal temperature, pressure, vibration, etc., the CSP unit automatically reduces its own output power based on the fast load reduction mechanism, and automatically switches to the isolated grid mode. That is, when a mechanical fault occurs in the CSP unit, the fast load reduction mechanism can be used to cut off the connection between the CSP unit and the energy storage unit, and reduce the output power to only meet the power supply to the basic power load of the independent grid, avoiding damage to the energy storage unit and the power equipment in the independent grid. When the fault of the CSP unit is resolved, the CSP unit can quickly restore the output of the power function based on the fast load reduction mechanism and adjust to the grid-connected mode.

[0042] Second embodiment Based on the same concept, the present invention also provides a solar thermal power generation control system applied to a plateau isolated grid energy station, which is used to execute the solar thermal power generation control method applied to a plateau isolated grid energy station as described in the first embodiment, including: The solar thermal power generation unit and the energy storage unit are in a separate or parallel state. When the solar thermal power generation unit and the energy storage unit are in a separate state, the solar thermal power generation unit is used to output load electric energy to an independent power grid. When the solar thermal power generation unit and the energy storage unit are in a parallel state, the solar thermal power generation unit is used to output load electric energy to an independent power grid and output storage electric energy to the energy storage unit.

[0043] In this embodiment, by flexibly and autonomously switching the solar thermal power generation unit between the isolated grid mode and the grid-connected mode, the power supply object and power supply strategy of the solar thermal power generation unit can be dynamically adjusted to effectively ensure the power demand and power supply safety and stability of the independent power grid.

[0044] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A method for controlling solar thermal power generation applied to isolated grid energy stations in plateaus, characterized in that: The steps include: S1: Detect and determine the separate and parallel states of the CSP unit and the energy storage unit. When the CSP unit and the energy storage unit are in separate states, switch the operation state of the CSP unit to the isolated grid mode. When the CSP unit and the energy storage unit are in parallel states, switch the operation state of the CSP unit to the grid-connected mode. S2: In the isolated grid mode, the CSP unit outputs load electric energy to the independent grid, and actively performs frequency and voltage regulation based on the power load of the independent grid; S3: In the grid-connected mode, the solar thermal power generation unit outputs load electric energy to the independent power grid and outputs storage electric energy to the energy storage unit.

2. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 1, characterized in that: In S2, in the isolated grid mode, the solar thermal power generation unit outputs load electric energy to the independent grid, which specifically includes the following steps: S21: when the CSP power generation unit is stopped and waiting to be started, the CSP power generation unit rotates the regulating stage blades of the CSP power generation steam turbine from a stationary state to a rated speed through a steam turbine digital electro-hydraulic control mechanism; S22: The speed of the regulating stage blades of the solar thermal power generation steam turbine is secondarily adjusted through a frequency rapid response mechanism to output load electric energy of corresponding output frequency and output voltage to the independent power grid.

3. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 2, characterized in that: When the solar thermal power generation unit has only one set of first solar thermal power generation electronic devices, the frequency rapid response mechanism includes a single-machine frequency and voltage regulation control mode, specifically including the following steps: S221: measuring real-time frequency data in the independent power grid by a frequency sensor, comparing the real-time frequency data with preset target frequency data, and directly adjusting the output frequency of the first solar thermal power generation electronic device based on the frequency difference between the real-time frequency data and the target frequency data; S222: measuring real-time voltage data in the independent power grid through a voltage transformer, comparing the real-time voltage data with preset target voltage data, and directly adjusting the output voltage of the first solar thermal power generation electronic device based on the voltage difference between the real-time voltage data and the target voltage data.

4. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 2, characterized in that: When the solar thermal power generation unit has a plurality of second solar thermal power generation electronic devices operating in parallel, the frequency rapid response mechanism includes a multi-machine frequency and voltage regulation control mode, specifically including the following steps: S223: measuring real-time frequency data in the independent power grid through a frequency sensor, comparing the real-time frequency data with preset target frequency data, obtaining a frequency demand of the independent power grid based on a frequency difference between the real-time frequency data and the target frequency data, and allocating the frequency demand of the independent power grid to the plurality of second CSP electronic devices in proportion according to different rated capacities of the plurality of second CSP electronic devices; S224: Measure the real-time voltage data in the independent power grid through a voltage transformer, compare the real-time voltage data with the preset target voltage data, obtain the voltage demand of the independent power grid based on the voltage difference between the real-time voltage data and the target voltage data, and distribute the voltage demand of the independent power grid to the plurality of the second solar thermal power generation electronic devices in proportion according to the different maximum reactive powers of the plurality of the second solar thermal power generation electronic devices.

5. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 3 or 4, characterized in that: The frequency fast response mechanism includes a manual frequency modulation and voltage regulation control mode, in which the output frequency and output voltage of the first photothermal electronic device or any of the second photothermal electronic devices are manually and independently controlled; When the first photovoltaic electronic device or any of the second photovoltaic electronic devices fails to automatically adjust the frequency and voltage, the photovoltaic power generation unit outputs an alarm and automatically switches from a single-machine frequency and voltage control mode or a multi-machine frequency and voltage control mode to a manual frequency and voltage control mode.

6. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 1, characterized in that: In the grid-connected mode, the CSP unit outputs load electric energy to the independent power grid according to the dispatching instruction output by the dispatching master station, and outputs storage electric energy to the energy storage unit.

7. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 6, characterized in that: In S3, in the grid-connected mode, the CSP unit outputs load electric energy to the independent power grid and outputs stored electric energy to the energy storage unit, which specifically includes the following steps: S31: respectively measuring the real-time frequency data in the independent power grid and the energy storage unit through a frequency sensor, comparing the real-time frequency data with the target frequency data recorded in the dispatch instruction, and adjusting the total output frequency of the CSP unit outputting load electric energy to the independent power grid and outputting stored electric energy to the energy storage unit based on the frequency difference between the real-time frequency data and the target frequency data; S32: Real-time voltage data of the independent power grid and the energy storage unit are measured respectively by voltage transformers, the real-time voltage data are compared with the target voltage data recorded in the dispatch instruction, and based on the voltage difference between the real-time voltage data and the target voltage data, the total output voltage of the solar thermal power generation unit to output load electric energy to the independent power grid and to output storage electric energy to the energy storage unit is adjusted.

8. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 1, characterized in that: The following steps are also included: S4: The solar thermal power generation unit compares the load electric energy output to the independent power grid and the stored electric energy output to the energy storage unit with the maximum limit of the SGS operating boundary respectively. When the active power value and / or reactive power value of the load electric energy or the stored electric energy exceeds the maximum limit of the SGS operating boundary, the maximum limit set by the SGS operating boundary is used as the final output active power value and / or reactive power value.

9. The method for controlling solar thermal power generation applied to a plateau isolated grid energy station according to claim 1, characterized in that: The CSP unit is provided with a rapid load reduction mechanism. When the CSP unit self-checks and finds a mechanical fault, the CSP unit automatically reduces its output power based on the rapid load reduction mechanism and automatically switches to the isolated grid mode.

10. A solar thermal power generation control system applied to isolated grid energy stations in plateaus, characterized in that: The method for controlling solar thermal power generation applied to a plateau isolated grid energy station as claimed in any one of claims 1 to 9 comprises: A photothermal power generation unit, wherein the photothermal power generation unit and the energy storage unit are in a separate or parallel state. When the photothermal power generation unit and the energy storage unit are in a separate state, the photothermal power generation unit is used to output load electric energy to an independent power grid. When the photothermal power generation unit and the energy storage unit are in a parallel state, the photothermal power generation unit is used to output load electric energy to the independent power grid and output storage electric energy to the energy storage unit.

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