A method and device for power grid dispatching in a large-machine small-grid power system

Abstract

The present application discloses a grid dispatching method and device in a large-machine and small-grid power system. Based on the extraction of digital features of the power grid and power supply points of various power generation types in the power system, it is determined that the emergency reserve capacity should be reserved and the capacity is configured; based on the output of the current power supply points of various power generation types, it is judged whether the current power system meets the large-machine and small-grid characteristics; if it meets the requirements, the power grid uses the configured emergency reserve capacity of various power generation types to dispatch the power supply points in the power system to adjust the voltage, and / or dispatch the power supply points in the power system to adjust the frequency; based on the stability control requirements of the frequency dynamic characteristic indicators of the entire power system, the expected load of the entire network and the unit characteristics of each power supply point, the power grid generates an output curve and sends power generation dispatching instructions to each power supply point. The present application effectively ensures the safety and stability of the power system under the large-machine and small-grid conditions through multiple rounds of adjustment of voltage, frequency and power.

Description

Technical Field

[0001] The present application relates to the technical field of power systems, and in particular to a power grid dispatching method and device in a large-machine small-grid power system. Background Art

[0002] "Large generators and small grid" is a special structure in the power system, which is characterized by a large proportion of the single-unit capacity of the generator set and a relatively small scale of the grid. With the continuous development of power technology, the single-unit capacity of the generator set is getting larger and larger. In some relatively isolated power systems, these large-capacity units need to be connected and operated with relatively small grids, thus forming a special pattern of large units and small grids. This structure may lead to stability problems of the grid when facing large disturbances, especially frequency stability problems. In the "large generator and small grid" power system, once events such as large unit tripping or sudden changes in large loads occur, the frequency and voltage of the grid may fluctuate greatly, and may even cause the grid to collapse. In some cases, it will also cause regional voltage collapse, endangering system safety, causing system shocks, and endangering the safety of large units. At present, there is a lack of scheduling solutions to ensure the safety and stability of the power system for large generators and small grids. Summary of the invention

[0003] Based on the above problems, the present application provides a power grid dispatching method and device in a large-machine small-grid power system, the purpose of which is to ensure the safety and stability of the power system.

[0004] The embodiments of the present application disclose the following technical solutions:

[0005] In a first aspect, the present application provides a power grid dispatching method in a large-machine small-grid power system, the method comprising:

[0006] Based on the digital feature extraction of the power grid and power supply points of various power generation types in the power system, determine the emergency reserve capacity of various power generation types that should be reserved in the power system and configure the emergency reserve capacity;

[0007] Based on the output of the power source points of the multiple power generation types, judging whether the current power system meets the characteristics of large machine and small grid;

[0008] If it is determined that the current power system meets the characteristics of large machines and small grids, the power grid utilizes the configured emergency reserve capacity of multiple power generation types to dispatch power supply points in the power system for voltage adjustment based on a voltage multi-round adjustment scheme, and / or dispatches power supply points in the power system for frequency adjustment based on a frequency multi-round adjustment scheme; the voltage multi-round adjustment scheme includes: voltage multi-round adjustment methods, voltage multi-round adjustment ranges, and voltage multi-round adjustment priority information for the multiple power generation types; the frequency multi-round adjustment scheme includes: frequency multi-round adjustment methods, frequency multi-round adjustment ranges, and frequency multi-round adjustment priority information for the multiple power generation types;

[0009] Based on the stability control requirements of the frequency dynamic characteristic index of the whole network of the power system, the expected load of the whole network and the characteristics of the units of each power source point, the power grid generates the output curve of the units of each power source point in the future period; the frequency dynamic characteristic index is used to numerically characterize the power change of the whole network required to cause the unit frequency change of the power system;

[0010] The power grid sends a power generation dispatching instruction to each power source point to adjust the power; the power generation dispatching instruction includes an output curve of the unit at the corresponding power source point.

[0011] In an optional implementation, the voltage multi-round adjustment range includes: photovoltaic, hydropower, nuclear power, thermal power and energy storage; the voltage multi-round adjustment priority information includes: photovoltaic>hydropower>nuclear power>thermal power>energy storage;

[0012] The multiple rounds of voltage adjustments include: four basic rounds of voltage adjustments corresponding to photovoltaic, hydropower, nuclear power and thermal power, and one accident round of voltage adjustments corresponding to fault conditions;

[0013] The voltage multi-round adjustment method includes: the action voltage and delay of the first basic round, the action voltage difference and delay of the remaining basic rounds, and the action voltage and delay of the accident round.

[0014] In an optional implementation, the action voltage of the first basic wheel is 0.84 pu, and the delay is 15 to 20 s;

[0015] The action voltage difference of the remaining basic wheels is 0.01pu, and the delay is 0.2s;

[0016] The operating voltage of the accident wheel is 0.8pu and the delay is 0.1s.

[0017] In an optional implementation, the configured emergency reserve capacity of various power generation types is used to adjust the voltage based on a multi-round voltage adjustment scheme, including:

[0018] If the voltage of the power system is as low as 0.84 pu, the voltage adjustment corresponding to the first basic round of photovoltaic is started and lasts for 15 to 20 seconds; during the voltage adjustment of the first basic round, a part of the photovoltaic emergency reserve capacity is injected into the power grid;

[0019] If the voltage adjustment effect of the first basic round does not achieve the expected effect, when the voltage of the power system drops to 0.83pu, the second basic round of voltage adjustment corresponding to the hydropower is started and lasts for 0.2s; during the voltage adjustment period of the second basic round, a part of the emergency reserve capacity of the hydropower is injected into the power grid;

[0020] If the voltage adjustment effect of the second basic round does not achieve the expected effect, when the voltage of the power system drops to 0.82pu, the third basic round of voltage adjustment corresponding to the nuclear power is started and lasts for 0.2s; during the voltage adjustment period of the third basic round, a part of the emergency reserve capacity of the nuclear power is injected into the power grid;

[0021] If the voltage adjustment effect of the third basic round does not achieve the expected effect, when the voltage of the power system drops to 0.81pu, the fourth basic round of voltage adjustment corresponding to thermal power is started and lasts for 0.2s; during the fourth basic round of voltage adjustment, a part of the emergency reserve capacity of thermal power is injected into the power grid;

[0022] If the voltage adjustment effect of the fourth basic round fails to achieve the expected effect, and the voltage of the power system is monitored to be as low as 0.8pu, the voltage adjustment of the accident round is started, the load is cut off or the energy storage system is started; during the voltage adjustment of the accident round, all or part of the remaining accident reserve capacity of each power generation type is injected into the power grid.

[0023] In an optional implementation, the frequency multi-round adjustment range includes: thermal power, hydropower, nuclear power and energy storage; the frequency multi-round adjustment priority information includes: thermal power>hydropower>nuclear power>energy storage;

[0024] The multiple rounds of frequency adjustments include: three basic rounds of frequency adjustments corresponding to thermal power, hydropower, and nuclear power, and one round of accident frequency adjustments corresponding to fault conditions;

[0025] The frequency multi-round adjustment method includes: the action frequency and delay of the first basic wheel, the action frequency difference and delay of the remaining basic wheels, and the action frequency and delay of the accident wheel.

[0026] In an optional implementation, the action frequency of the first basic wheel is 49.8 Hz, with a delay of 0.2 s;

[0027] The action frequency difference of the remaining basic wheels is 0.2 Hz, and the delay is 0.2 s;

[0028] The operating frequency of the accident wheel is 49.2 Hz, with a delay of 0.1 s.

[0029] In an optional implementation, the configured emergency reserve capacity of various power generation types is used to adjust the frequency based on a frequency multi-round adjustment scheme, including:

[0030] If the frequency of the power system drops to 49.8 Hz, the frequency adjustment corresponding to the first basic round of thermal power is started and lasts for 0.2 s; during the first basic round of frequency adjustment, a portion of the emergency reserve capacity of the thermal power is injected into the power grid;

[0031] If the frequency adjustment effect of the first basic round does not achieve the expected effect, when the frequency of the power system drops to 49.6 Hz, the second basic round of frequency adjustment corresponding to the hydropower is started and lasts for 0.2 s; during the second basic round of frequency adjustment, a part of the emergency reserve capacity of the hydropower is injected into the power grid;

[0032] If the frequency adjustment effect of the second basic round does not achieve the expected effect, when the frequency of the power system drops to 49.4 Hz, the third basic round of frequency adjustment corresponding to the nuclear power is started and lasts for 0.2 s; during the third basic round of frequency adjustment, a part of the nuclear power emergency reserve capacity is injected into the power grid;

[0033] If the frequency adjustment effect of the third basic round does not achieve the expected effect, wait until the frequency of the power system drops to 49.2Hz, start the frequency adjustment of the accident round, cut off the load or start the energy storage system; during the frequency adjustment of the accident round, all or part of the remaining accident reserve capacity of each power generation type will be injected into the power grid.

[0034] In an optional implementation, after the voltage adjustment is performed based on the voltage multi-round adjustment scheme, the method further includes:

[0035] The power grid controls the reactive power of some power supply points to compensate and adjust the voltage.

[0036] In an optional implementation, the step of adjusting the frequency based on a multi-round frequency adjustment scheme is performed after the step of compensating and adjusting the voltage by controlling the reactive power of the power supply points of the power grid control part is executed after frequency monitoring.

[0037] In an optional implementation, based on the stability control requirements of the frequency dynamic characteristic index of the whole network of the power system, the estimated whole network load and the characteristics of the units of each power source point, the power grid generates the output curve of the units of each power source point in the future period, including:

[0038] Determine the target value of the frequency dynamic characteristic index;

[0039] Based on the target value, the monitored frequency disturbance of the power system, the expected load of the entire network and the unit characteristics of each power source, the output curve of the units at each power source in the future period is generated, so as to control the power of each unit through the output curve, so that the deviation between the actual value of the frequency dynamic characteristic index and the target value is within the preset index floating range; the unit characteristics include the power change that the unit of the power source needs to provide for unit frequency change.

[0040] In an optional implementation, the generating of the output curve of the units at each power source point in the future period based on the target value, the monitored frequency disturbance of the power system, the estimated load of the entire network and the unit characteristics of each power source point includes:

[0041] Based on the target value, the monitored frequency disturbance of the power system, and the unit characteristics of each power source point, determine the power change amount that should be provided by the power source point of each power generation type so that the deviation amount between the actual value of the frequency dynamic characteristic index and the target value is within a preset index floating range;

[0042] Based on the predicted total grid load in the future period and the power variation that the power sources of each type of power generation should provide, the output curve of the units at each power source in the future period is generated.

[0043] In an optional implementation, after the voltage adjustment is performed based on the voltage multi-round adjustment scheme, the method further includes:

[0044] Performing deep learning based on the power receiving characteristics of the power grid before and after voltage adjustment and the power generation characteristics of the power supply points of the multiple power generation types to assist in monitoring the stability of the power grid;

[0045] After the frequency adjustment is performed based on the frequency multi-round adjustment scheme, the method further includes:

[0046] Deep learning is performed based on the power receiving characteristics of the power grid before and after frequency adjustment and the power generation characteristics of the power supply points of the multiple power generation types to assist in monitoring the stability of the power grid.

[0047] In an optional implementation, before determining whether the current power system meets the large-machine-small-grid feature, the method further includes:

[0048] The stability of the power grid is monitored in real time to identify whether the power grid has a risk of frequency or voltage drop.

[0049] In an optional implementation, judging whether the current power system meets the large-machine-small-grid feature based on the outputs of the power supply points of the multiple power generation types currently includes:

[0050] If the sum of the outputs of any two units in any current power source of any type of power generation exceeds 15% of the total capacity of the current power system, the power system is judged to meet the characteristics of large units and small grids.

[0051] A second aspect of the present application provides a power grid dispatching device in a large-machine small-grid power system, the device comprising:

[0052] A capacity configuration module is used to determine the emergency reserve capacity of various power generation types that should be reserved in the power system and configure the emergency reserve capacity based on the digital feature extraction of the power grid and power supply points of various power generation types in the power system;

[0053] A working condition judgment module, used to judge whether the current power system meets the characteristics of large machine and small grid based on the output of the power source points of the current multiple power generation types;

[0054] An adjustment module, for, if it is determined by the working condition judgment module that the current power system meets the characteristics of large machine and small grid, the power grid utilizes the configured emergency reserve capacity of multiple power generation types, and dispatches the power supply points in the power system to perform voltage adjustment based on a voltage multi-round adjustment scheme, and / or dispatches the power supply points in the power system to perform frequency adjustment based on a frequency multi-round adjustment scheme; the voltage multi-round adjustment scheme includes: voltage multi-round adjustment methods, voltage multi-round adjustment ranges and voltage multi-round adjustment priority information for the multiple power generation types; the frequency multi-round adjustment scheme includes: frequency multi-round adjustment methods, frequency multi-round adjustment ranges and frequency multi-round adjustment priority information for the multiple power generation types;

[0055] An output curve generation module is used for generating output curves of the units at each power source point in the future period of the power grid based on the stability control requirements of the frequency dynamic characteristic index of the whole network of the power system, the estimated load of the whole network and the characteristics of the units at each power source point; the frequency dynamic characteristic index is used to numerically characterize the power change of the whole network required to cause the unit frequency change of the power system;

[0056] The dispatching instruction sending module is used for the power grid to send power generation dispatching instructions to each power source point to adjust the power; the power generation dispatching instruction includes the output curve of the unit of the corresponding power source point.

[0057] Compared with the prior art, this application has the following beneficial effects:

[0058] The present application discloses a power grid dispatching method in a large-machine and small-grid power system. Based on the digital feature extraction of the power grid and power supply points of various power generation types in the power system, the emergency reserve capacity to be reserved is determined and the capacity is configured; based on the output of the current power supply points of various power generation types, it is judged whether the current power system meets the characteristics of a large-machine and small-grid; if it meets the requirements, the power grid uses the configured emergency reserve capacity of various power generation types to dispatch the power supply points in the power system for voltage adjustment, and / or dispatch the power supply points in the power system for frequency adjustment; based on the stability control requirements of the frequency dynamic characteristic indicators of the entire power system, the expected load of the entire network and the unit characteristics of each power supply point, the power grid generates an output curve and sends a power generation dispatching instruction to each power supply point. The present application combines the pre-configured emergency reserve capacity to provide capacity support for voltage adjustment and frequency adjustment under large-machine and small-grid conditions; and also adjusts the output curve to achieve power adjustment of each unit based on the stability control requirements of the frequency dynamic characteristic indicators. Through multiple rounds of adjustment in various forms of voltage, frequency and power, the safety and stability of the power system under large-machine and small-grid conditions are effectively guaranteed. By applying the technical solution of the present application, it is possible to effectively improve the power supply stability and reliability of countries whose power systems have the characteristics of large units and small grids, and reduce the problem of grid collapse caused by events such as large unit tripping or sudden changes in large loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0060] Figure 1 A schematic diagram of an application scenario of a power grid dispatching method in a large-machine small-grid power system provided in an embodiment of the present application;

[0061] Figure 2 An exemplary flow chart of a method for dispatching electric power in a large-scale power system with a small grid provided in an embodiment of the present application;

[0062] Figure 3 A schematic diagram of a multi-round voltage adjustment provided in an embodiment of the present application;

[0063] Figure 4 A schematic diagram of a frequency multi-round adjustment provided in an embodiment of the present application;

[0064] Figure 5 Another exemplary flow chart of the power dispatching method in the large-machine small-grid power system provided in the embodiment of the present application;

[0065] Figure 6A power dispatch signaling diagram in a large-machine and small-grid power system provided in an embodiment of the present application;

[0066] Figure 7 A structural schematic diagram of a power dispatching device in a large-machine and small-grid power system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0067] As described above, the current large-scale power generation and small-grid power system structure may lead to stability problems in the face of large disturbances, especially frequency stability problems. Once a large unit trips or a sudden change in large load occurs, it may cause a large fluctuation in the frequency and voltage of the power grid, and may even cause the grid to collapse. In some cases, it may also cause regional voltage collapse, endangering system safety, causing system shocks, and endangering the safety of large units.

[0068] For power systems with large generators and small grids, the grid's ability to resist large disturbances is weak. Regional load fluctuations, unit failures, or voltage collapses threaten system safety, causing system shocks and also threatening the safety of large generators. Currently, there is a lack of dispatching solutions to ensure the safety and stability of power systems with large generators and small grids.

[0069] To solve the above problems, the inventors have provided a grid dispatching method and device in a large-machine and small-grid power system after research. In the case of a large machine and a small grid, the impact of power generation points on the grid cannot be ignored. Power points of different power generation types have different characteristics, so a multi-round voltage adjustment scheme and a multi-round frequency adjustment scheme are designed specifically for this purpose. For a power system with large machine and small grid characteristics, when conducting grid dispatch, multi-round voltage adjustment, multi-round frequency adjustment and power adjustment are used as three adjustment "handles". Combined with the pre-configured emergency reserve capacity, capacity support is provided for voltage adjustment and frequency adjustment under large machine and small grid conditions. In addition, the frequency dynamic characteristic index of the entire network is used as a stability target, and the unit output curve is generated by combining the expected full network load and the unit characteristics of each power source point to dispatch the unit's future output power. Through multiple rounds of adjustment in various forms of voltage, frequency and power, the safety and stability of the power system under large machine and small grid conditions can be effectively guaranteed. By applying the technical solution of the present application, it is possible to effectively improve the power supply stability and reliability of countries whose power systems have the characteristics of large units and small grids, and reduce the problem of grid collapse caused by events such as large unit tripping or sudden changes in large loads.

[0070] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0071] Figure 1 The following is a schematic diagram of an application scenario of a power grid dispatching method in a large-scale small-grid power system provided in an embodiment of the present application. Figure 1 As shown, in actual applications, power sources of various different types of power generation (such as photovoltaic, thermal, wind, nuclear, and hydropower) may communicate with the grid and transmit power. These different types of power sources can be collectively referred to as the power plant side. In the embodiment of the present application, the power plant side can report its own data to the grid side and provide timely feedback; the grid side can dispatch the power plant side, such as voltage, frequency, power, etc. Figure 1 It can be seen that in the actual power production process, the grid side and the power plant side need to be closely dispatched to achieve better and more stable power supply and maintain the cost demands of both parties.

[0072] In actual scenarios, the configuration of the power plant side is not limited to Figure 1 There are several types of power points shown in, that is, Figure 1 It does not limit the types of power source points in the scenario of the grid dispatch method in the large-scale small-grid power system in this solution. In addition, according to the differences in the power development level, basic power facilities, and abundance of natural resources in various countries, the power source structure of some countries' power systems may only include Figure 1 Some types of power supply points shown in . For example, some countries have only two types of power supply structures, nuclear power and thermal power, while some countries rely on photovoltaic and hydropower, etc. The grid dispatching method in the machine-small grid power system described in the technical solution of this application is introduced by taking the power system with nuclear power, photovoltaic, hydropower and thermal power as an example. In scenarios with other power supply structures, according to the technical concepts introduced in the technical solution of this application, it is also possible to realize the dispatching of large-machine and small-grid working conditions to ensure the safe and stable operation of the power system.

[0073] See also Figure 2 , which is an example flow chart of a method for dispatching power in a large-scale small-grid power system provided by an embodiment of the present application. The method is described in detail below. Figure 2 The present application provides a method for dispatching a power grid in a large-scale small-grid power system, comprising the following steps:

[0074] S201. Based on the digital feature extraction of the power grid and power supply points of various power generation types in the power system, determine the emergency reserve capacity of various power generation types that should be reserved in the power system and configure the emergency reserve capacity.

[0075] In the embodiment of the present application, in order to carry out the dispatch of the large-machine small-grid power system, spare capacity is prepared in advance for adjusting the dispatch. In the present application, the prepared spare capacity is referred to as the accident spare capacity. In the specific implementation, the production factor data of the power grid and the power supply points of various power generation types can be first collected or received, and digital feature extraction can be performed. Among them, the production factor data provided by the power supply point is the characteristic production factor data, and the production factor data of the power grid is the control production factor data.

[0076] The technical solution of this application pre-plans a characteristic production factor group and a control production factor group. Among them, the characteristic production factor group includes characteristic production factors of multiple levels, such as first-level characteristic production factors, second-level characteristic production factors and third-level characteristic production factors of various different power generation types. The following is an illustrative introduction to several first-level characteristic production factors in combination with different power generation types. Taking photovoltaic power generation as an example, the first-level characteristic production factors may include: photovoltaic light illumination. Taking hydropower generation as an example, the first-level characteristic production factors may include: precipitation (water inflow), etc. Taking thermal power generation as an example, the first-level characteristic production factors may include: low calorific value of coal, coal consumption, heat consumption, etc. Taking wind power generation as an example, the first-level characteristic production factors may include: wind speed, etc.

[0077] For thermal power plants, a single system can be a boiler system, an electrical system, etc. For hydropower plants, a single system can be a turbine system, a switching system, a butterfly valve layer system, etc. For photovoltaic power plants, a single system can be a photovoltaic panel area, a substation area, etc. In addition, these different power plants also share a transmission and transformation system. Correspondingly, the secondary characteristic production factors can be production factors that reflect a single system, such as furnace efficiency and steam turbine efficiency. Tertiary characteristic production factors can be production factors that reflect the overall situation of multiple systems, such as photovoltaic efficiency, hydropower efficiency, thermal power unit efficiency, and power plant thermal efficiency (specific heat index). From Figure 2 It can be seen that the mining level of data features is gradually deepened from the first-level characteristic production factors, the second-level characteristic production factors, and the third-level characteristic production factors. It can be seen that in the embodiment of the present application, relying on the division structure of the characteristic production factors in the characteristic production factor group, the data of natural characteristics, single system characteristics and plant system characteristics can be collaboratively extracted, and digital power analysis can be realized from the characteristics of multiple levels.

[0078] The control production factor group includes multiple aspects of control production factors. In the embodiment of the present application, for example, it can include but is not limited to the following six aspects of control production factors: (1) electricity price; (2) inertia and frequency; (3) active and reactive power; (4) electricity carbon emissions; (5) safety and stability; and (6) grid connection and disconnection.

[0079] In an embodiment of the present application, based on the extraction of digital features of the power grid and power supply points of various power generation types in the power system, the emergency reserve capacity of various power generation types that should be reserved in the power system can be determined and the emergency reserve capacity can be configured. As an example, based on the extraction of digital features of the power grid and power supply points of various power generation types, it is possible to understand the ability levels of various types of power supply points in adjusting the voltage stability of the power system, the ability levels in adjusting the frequency stability of the voltage system, and the frequency dynamic characteristics of each power supply point in different load periods (such as different load climbing periods and descending periods). Based on this, the power system can calculate which type of power supply point should be configured with more emergency reserve capacity and which type of power supply point should be configured with less emergency reserve capacity.

[0080] As an example, for power sources with large system inertia (such as thermal power plants), 50% of the emergency reserve capacity is configured for thermal power spinning reserve. In addition, a portion of the photovoltaic emergency reserve capacity can also be configured to achieve photovoltaic reactive power increase and decrease.

[0081] S202. Based on the outputs of the power supply points of the multiple power generation types, determine whether the current power system meets the characteristics of large machines and small grids. If it is determined that the current power system meets the characteristics of large machines and small grids, proceed to step S203.

[0082] In an embodiment of the present application, a method for determining whether a power system meets the characteristics of a large machine and a small grid is exemplarily provided: if the sum of the outputs of any two units in any current power source of any power generation type exceeds 15% of the total capacity of the current power system, the power system is determined to meet the characteristics of a large machine and a small grid. In this example, the proportion of the capacity of multiple units in the total capacity of the entire power system is combined to evaluate whether the power system meets the characteristics of a large machine and a small grid. Compared with the evaluation based on the capacity of a single unit, it has a higher dynamic recognition ability. It should be noted that the above threshold value of 15% is only used as an example. In specific implementation, other threshold values ​​may be set, such as 16%, 18%, etc., in combination with the strictness or sensitivity of the requirements for the identification of the characteristics of a large machine and a small grid. This is not limited here.

[0083] S203. The power grid utilizes the configured emergency reserve capacity of various power generation types to schedule the power sources in the power system for voltage adjustment based on a multi-round voltage adjustment scheme, and / or schedules the power sources in the power system for frequency adjustment based on a multi-round frequency adjustment scheme.

[0084] It is proposed in this step that the configured emergency reserve capacity can be used to adjust the voltage and / or frequency. Generally speaking, combined with the difficulty of adjustment, the power grid gives priority to voltage adjustment. If the expected effect cannot be achieved after the voltage adjustment, the power grid can further adopt frequency adjustment. If the expected effect is achieved after the voltage adjustment, the frequency adjustment may not be continued. In addition, in some possible implementation scenarios, voltage adjustment and frequency adjustment may not be prioritized. For example, the power grid simultaneously adjusts the voltage and frequency of the power source. In the embodiment of the present application, the example of first adjusting the voltage and then adjusting the frequency is used for explanation.

[0085] For ease of understanding, the voltage multi-round adjustment scheme and the frequency multi-round adjustment scheme involved in this application are introduced and described in detail below.

[0086] The voltage multi-round adjustment scheme and the frequency multi-round adjustment scheme, among which the specific voltage adjustment method and frequency adjustment method within a single power source point can be uploaded by the power source point to the power grid, and then collected by the power grid and incorporated into the voltage multi-round adjustment scheme and the frequency multi-round adjustment scheme.

[0087] The voltage multi-round adjustment scheme includes: voltage multi-round adjustment methods for the multiple power generation types, voltage multi-round adjustment ranges and voltage multi-round adjustment priority information. In the present application, multi-round adjustment of voltage specifically refers to the first round, second round, third round and other rounds for power sources of different power generation types, and the voltage is gradually adjusted.

[0088] In one example, the multi-round voltage adjustment range includes: photovoltaic, hydropower, nuclear power, thermal power and energy storage; the multi-round voltage adjustment priority information includes: photovoltaic> hydropower> nuclear power> thermal power> energy storage. That is, photovoltaic is the highest priority in the multi-round voltage adjustment. This is because the cost of photovoltaic adjustment is relatively low, and it supports the reactive power control of the power grid to avoid voltage drop at almost no cost. This is a significant advantage of photovoltaic power sources in voltage adjustment. The multi-round voltage adjustment includes: voltage adjustment of four basic rounds corresponding to photovoltaic, hydropower, nuclear power and thermal power, and voltage adjustment of one accident round corresponding to the fault situation. Combined with the multi-round voltage adjustment priority information introduced above, in the multi-round voltage adjustment, photovoltaic adjustment is the first basic round in the four basic rounds, and the remaining second basic round is hydropower adjustment, the third basic round is nuclear power adjustment, and the fourth basic round is thermal power adjustment. If the adjustment fails to achieve the expected effect until the voltage adjustment of thermal power, it is determined that an accident has occurred and the accident round needs to be started, and the load is cut off or the energy storage system is started.

[0089] The multi-round voltage adjustment method includes: the action voltage and delay of the first basic round, the action voltage difference and delay of the remaining basic rounds, and the action voltage and delay of the accident round. As an example, the action voltage of the first basic round is 0.84pu, with a delay of 15-20s; the action voltage difference of the remaining basic rounds (i.e., the second, third and fourth basic rounds) is 0.01pu, with a delay of 0.2s; the action voltage of the accident round is 0.8pu, with a delay of 0.1s. The delay of the first basic round is relatively long, because in a power system where photovoltaic power accounts for a large proportion, reactive power injection requires a certain amount of time. Combined with actual needs and the proportion and configuration of the power supply structure, the delay can be set adaptively, and the action voltage can also be set according to needs.

[0090] Figure 3 A schematic diagram of a multi-round voltage adjustment is provided in an embodiment of the present application. The figure shows the action area and recovery area of ​​each round of the multi-round voltage adjustment. In combination with the multi-round voltage adjustment method described in the above example, in an embodiment of the present application, the voltage is adjusted based on the multi-round voltage adjustment scheme by utilizing the configured emergency reserve capacity of multiple power generation types, including:

[0091] (1) If the voltage of the power system drops to 0.84 pu, the first basic round of voltage adjustment corresponding to photovoltaic power generation is started and lasts for 15 to 20 seconds. During the first basic round of voltage adjustment, a portion of the photovoltaic power generation emergency reserve capacity is injected into the power grid. If the voltage recovers to above 0.84 pu after the first basic round of voltage adjustment, it is considered that this round has achieved the expected effect and the current round is exited.

[0092] (2) If the voltage adjustment effect of the first basic round does not achieve the expected effect, wait until the voltage of the power system drops to 0.83pu, start the second basic round of voltage adjustment corresponding to hydropower and continue for 0.2s; during the second basic round of voltage adjustment, inject a part of the emergency reserve capacity of hydropower into the power grid; if the voltage recovers to above 0.83pu after the second basic round of voltage adjustment, it is considered that this round has achieved the expected effect, and return to the previous round.

[0093] (3) If the voltage adjustment effect of the second basic round does not achieve the expected effect, wait until the voltage of the power system drops to 0.82pu, start the third basic round of voltage adjustment corresponding to nuclear power and continue it for 0.2s; during the third basic round of voltage adjustment, inject a part of the nuclear power emergency reserve capacity into the power grid; if the voltage recovers to above 0.82pu after the third basic round of voltage adjustment, it is considered that this round has achieved the expected effect, and return to the previous round.

[0094] (4) If the voltage adjustment effect of the third basic round does not achieve the expected effect, wait until the voltage of the power system drops to 0.81pu, start the fourth basic round of voltage adjustment corresponding to thermal power and continue for 0.2s; during the fourth basic round of voltage adjustment, inject a part of the emergency reserve capacity of thermal power into the power grid; if the voltage recovers to above 0.81pu after the fourth basic round of voltage adjustment, it is considered that this round has achieved the expected effect, and return to the previous round.

[0095] (5) If the voltage adjustment effect of the fourth basic round does not achieve the expected effect, and the voltage of the power system is monitored to be as low as 0.8pu, the voltage adjustment of the accident round is started, the load is cut off or the energy storage system is started; during the voltage adjustment of the accident round, all or part of the remaining accident reserve capacity of each type of power generation is injected into the power grid. If the voltage is restored to above 0.8pu after the voltage adjustment of the accident round, it is considered that this round has achieved the expected effect, and the previous round is returned.

[0096] When the accident wheel is started, the load must be appropriately cut off. At this time, the load of the power system must be adjusted to be greater than the imbalance of power generation at the power source point. Two methods can be used. One is to gradually cut off the load according to its importance (prioritize the load with lower importance), and the other is to start the energy storage system to increase the power input outside the existing power source point to ensure the stability and balance of the power system.

[0097] Combined with the above introduction, the action voltage that triggers the first round of basic round voltage adjustment is 0.84pu, the action voltage that triggers the second round of basic round voltage adjustment is 0.83pu, the action voltage that triggers the third round of basic round voltage adjustment is 0.82pu, the action voltage that triggers the fourth round of basic round voltage adjustment is 0.81pu, and the action voltage that triggers the accident round voltage adjustment is 0.8pu. Figure 3 As shown, when the voltage adjustment is restored to the corresponding value, the protection action returns and each round of voltage regulation is gradually exited.

[0098] The frequency multi-round adjustment scheme includes: the frequency multi-round adjustment mode for the multiple power generation types, the frequency multi-round adjustment range and the frequency multi-round adjustment priority information. In the present application, the frequency multi-round adjustment specifically refers to the first round, the second round, the third round and other rounds for power sources of different power generation types, and the frequency is gradually adjusted.

[0099] In one example, the range of multiple rounds of frequency adjustment includes: thermal power, hydropower, nuclear power and energy storage; the multiple rounds of frequency adjustment priority information includes: thermal power>hydropower>nuclear power>energy storage. That is, thermal power is the highest priority in the multiple rounds of frequency adjustment. The multiple rounds of frequency adjustment include: frequency adjustment corresponding to three basic rounds of thermal power, hydropower and nuclear power, and frequency adjustment corresponding to one round of accident rounds of fault conditions. Combined with the multiple rounds of frequency adjustment priority information introduced above, in the multiple rounds of frequency adjustment, the thermal power adjustment is the first basic round of the three basic rounds, the remaining second basic round is hydropower adjustment, and the third basic round is nuclear power adjustment. If the adjustment fails to achieve the expected effect until the voltage of nuclear power is adjusted, it is determined that an accident has occurred and it is necessary to start the accident round, cut off the load or start the energy storage system.

[0100] The frequency multi-round adjustment method includes: the action frequency and delay of the first basic wheel, the action frequency difference and delay of the remaining basic wheels, and the action frequency and delay of the accident wheel. As an example, the action frequency of the first basic wheel is 49.8Hz, with a delay of 0.2s; the action frequency difference of the remaining basic wheels (i.e., the second and third basic wheels) is 0.2Hz, with a delay of 0.2s; the action frequency of the accident wheel is 49.2Hz, with a delay of 0.1s. Combined with actual needs and the proportion and configuration of the power supply structure, the delay can be set adaptively, and the action frequency can also be set according to needs.

[0101] Figure 4 A schematic diagram of a frequency multi-round adjustment provided in an embodiment of the present application. The figure shows the action area and recovery area of ​​each round of frequency multi-round adjustment. In combination with the frequency multi-round adjustment method described in the above example, in an embodiment of the present application, the frequency is adjusted based on the frequency multi-round adjustment scheme using the configured emergency reserve capacity of multiple power generation types, including:

[0102] (1) If the frequency of the power system drops to 49.8 Hz, the first basic round of frequency adjustment corresponding to thermal power is started and lasts for 0.2 s; during the first basic round of frequency adjustment, a portion of the emergency reserve capacity of thermal power is injected into the power grid; if the frequency recovers to above 49.8 Hz after the first basic round of frequency adjustment, it is considered that this round has achieved the expected effect and is exited.

[0103] (2) If the frequency adjustment effect of the first basic round does not achieve the expected effect, when the frequency of the power system drops to 49.6 Hz, the second basic round of frequency adjustment corresponding to hydropower is started and lasts for 0.2 s; during the second basic round of frequency adjustment, a part of the emergency reserve capacity of hydropower is injected into the power grid; if the frequency recovers to above 49.6 Hz after the second basic round of frequency adjustment, it is considered that this round has achieved the expected effect, and the previous round is returned.

[0104] (3) If the frequency adjustment effect of the second basic round does not achieve the expected effect, when the frequency of the power system drops to 49.4 Hz, the third basic round of frequency adjustment corresponding to the nuclear power is started and lasts for 0.2 s; during the third basic round of frequency adjustment, a part of the nuclear power emergency reserve capacity is injected into the power grid; if the frequency recovers to above 49.4 Hz after the third basic round of frequency adjustment, it is considered that this round has achieved the expected effect, and the previous round is returned.

[0105] (4) If the frequency adjustment effect of the third basic round does not achieve the expected effect, when the frequency of the power system drops to 49.2 Hz, the frequency adjustment of the accident round is started, the load is cut off or the energy storage system is started; during the frequency adjustment of the accident round, all or part of the remaining accident reserve capacity of each type of power generation is injected into the power grid.

[0106] Combined with the above introduction, the action frequency that triggers the first round of basic wheel frequency adjustment is 49.8Hz, the action frequency that triggers the second round of basic wheel frequency adjustment is 49.6Hz, the action frequency that triggers the third round of basic wheel frequency adjustment is 49.4Hz, and the action frequency that triggers the accident wheel frequency adjustment is 49.2Hz. Figure 4 As shown, when the frequency adjustment is restored to the corresponding value, the protection action returns and gradually exits each round of frequency adjustment. It should be noted that the action frequency and action voltage of the embodiments of the present application can be determined by learning based on historical data. In addition, based on the differences in different regions and networks, the action frequency and action voltage can also be flexibly set according to the region, network and needs. The action frequencies and action voltages of each round in the above embodiments are all examples and are not intended to limit the scope of protection and specific implementation.

[0107] Through the voltage adjustment and / or frequency adjustment, the multi-round comprehensive dispatching of the power grid for various types of power sources in the large-scale small-grid power system is realized, which is beneficial to improving the anti-disturbance capability of the large-scale small-grid power system. An effective solution is provided to maintain the safety and stability of the large-scale small-grid power system. Furthermore, in the embodiment of the present application, the output curve of each unit can also be generated in combination with the stability control requirements of the frequency dynamic characteristic indicators of the entire network, so as to dispatch the corresponding unit to perform power generation work in the future time period according to the output curve, see S204~S205 for details.

[0108] S204: Based on the stability control requirements of the frequency dynamic characteristic indicators of the entire power system, the estimated load of the entire network and the characteristics of the units at each power source, the power grid generates an output curve of the units at each power source in the future period.

[0109] The power system produces and consumes electric energy simultaneously, and the power provided by the system must match the power consumption. When the active power balance of the power system is suddenly disrupted, the frequency of the system will transition from a normal stable value to another stable value. This frequency change process reflects the frequency dynamic characteristics of the system. In this application, the frequency dynamic characteristic index is used to numerically characterize the power change of the entire network required to cause a unit frequency change in the power system.

[0110] The frequency dynamic characteristics of the power system are related to factors such as the output of the generator set and the speed regulation system, the size and characteristics of the load, etc. For a large-capacity system with a small grid, on the one hand, the difference in active power caused by the loss of a large-capacity unit is large, and on the other hand, the system frequency regulation characteristics are relatively weak, so the system frequency fluctuates greatly. The frequency dynamic characteristic index (K value) is defined to reflect the impact of the capacity of the lost units in the power system on the change of the grid frequency. The expression of this index is: K= |ΣΔP / ΔF|. In the formula, ΔP is the power change of a unit of a certain type of power generation, ΣΔP represents the sum of the power changes of the entire grid, and ΔF is the system frequency change.

[0111] The power system has a stability control requirement for the frequency dynamic characteristic indicators of the system. If the K value fluctuates frequently and significantly, the safety and stability of the entire network will be put to the test. It is very likely that the power system will collapse due to the instability of the K value and will be unable to provide stable electricity to users. In this application, it is proposed to stabilize the K value at the target value when scheduling in a large-scale small-grid power system to avoid the above problems.

[0112] In this step, based on the stability control requirements of the frequency dynamic characteristic indicators of the entire power system, the estimated load of the entire network and the characteristics of the units at each power source, the power grid generates the output curve of the units at each power source in the future period, which may include:

[0113] Determine the target value of the frequency dynamic characteristic index; then based on the target value, the monitored frequency disturbance of the power system, the expected load of the entire network and the characteristics of the units at each power source, generate the output curve of the units at each power source in the future period, so as to control the power of each unit through the output curve, so that the deviation between the actual value of the frequency dynamic characteristic index and the target value is within the preset indicator floating range. The unit characteristics include the power change that the unit at the power source needs to provide for the unit frequency change.

[0114] In an embodiment of the present application, the target value can be calculated based on monitoring the power change and frequency change before a large disturbance occurs in the power system. After that, when a system disturbance occurs again (such as unit tripping, shedding, grid short circuit, etc.), the target value is combined to generate the future output curve. Considering that it may be difficult to accurately control the K value at the target value each time, and it is difficult to achieve accurately, in this application, in order to achieve stability, when generating the output curve, it is possible to strive to control the deviation between the actual value of the K value and the target value within a preset indicator floating range. The indicator floating range can be a specific numerical value (the unit is the same as the unit of the K value) or a percentage, such as ±3%.

[0115] In one possible implementation, based on the target value, the monitored frequency disturbance of the power system, and the unit characteristics of each power source point, the power change that each power generation type should provide is determined so that the deviation between the actual value of the frequency dynamic characteristic index and the target value is within a preset index floating range; based on the expected total network load in the future time period and the determined power change that each power generation type should provide, the output curve of the unit at each power source point in the future time period is generated.

[0116] For example, when the system is subject to a frequency disturbance of 0.5Hz, according to the target value (assuming 20MW / Hz), it is determined that the degree of power adjustment required is 10MW. At this time, if thermal power executes 10MW, this frequency disturbance can be met. If thermal power + new energy meet the stable demand of K value, due to the different inertia of hydropower and thermal power systems (which can be understood as different unit characteristics), thermal power and new energy are matched with each other and their respective division of labor adjusts the power change, and the power change that different power sources should provide can be determined.

[0117] In practical applications, the various types of power generation in the power grid are different, which directly affects the denominator of the K value calculation formula, resulting in different frequency changes. The power changes of the power points related to the numerator in the K value calculation formula can also be assigned different weights, representing the contribution of different types of power points in the power adjustment. In order to keep the K value stable, the change of the total power in the numerator of the formula is affected. Finally, based on the K value and the forecast of the entire network load (for example, the forecast of the entire network load in the next 24 hours), the output curve of the units of each type of power source can be determined for the next 24 hours to guide the unit power generation.

[0118] S205: The power grid sends a power generation dispatching instruction to each power source point to adjust power.

[0119] After S204 is executed, the power grid sends a power generation dispatching instruction including the unit output curve to each power source point, so that the unit can generate power according to the output curve according to the received power generation dispatching instruction.

[0120] The present application discloses a power grid dispatching method in a large-machine and small-grid power system. Based on the digital feature extraction of the power grid and power supply points of various power generation types in the power system, the emergency reserve capacity to be reserved is determined and the capacity is configured; based on the output of the current power supply points of various power generation types, it is judged whether the current power system meets the characteristics of a large-machine and small-grid; if it meets the requirements, the power grid uses the configured emergency reserve capacity of various power generation types to dispatch the power supply points in the power system for voltage adjustment, and / or dispatch the power supply points in the power system for frequency adjustment; based on the stability control requirements of the frequency dynamic characteristic indicators of the entire power system, the expected load of the entire network and the unit characteristics of each power supply point, the power grid generates an output curve and sends a power generation dispatching instruction to each power supply point. The present application combines the pre-configured emergency reserve capacity to provide capacity support for voltage adjustment and frequency adjustment under large-machine and small-grid conditions; and also adjusts the output curve to achieve power adjustment of each unit based on the stability control requirements of the frequency dynamic characteristic indicators. Through multiple rounds of adjustment in various forms of voltage, frequency and power, the safety and stability of the power system under large-machine and small-grid conditions are effectively guaranteed. By applying the technical solution of the present application, it is possible to effectively improve the power supply stability and reliability of countries whose power systems have the characteristics of large units and small grids, and reduce the problem of grid collapse caused by events such as large unit tripping or sudden changes in large loads.

[0121] Figure 5 Another example flow chart of the power dispatching method in the large-scale small-grid power system provided in the embodiment of the present application. Figure 2 In the process, Figure 5 The voltage is adjusted first and then the frequency is adjusted. Figure 5 As shown, before judging whether the current power system meets the characteristics of large machine and small network, the method also includes: real-time monitoring of the stability of the power grid to identify whether the power grid has the risk of frequency or voltage drop. After the voltage adjustment is performed based on the voltage multi-round adjustment scheme, the method also includes: the power grid controls the reactive power of some power supply points to compensate and adjust the voltage. The step of adjusting the frequency based on the frequency multi-round adjustment scheme is performed after the step of controlling the reactive power of some power supply points to compensate and adjust the voltage is performed and after frequency monitoring. After the voltage adjustment is performed based on the voltage multi-round adjustment scheme, the method also includes: based on the power receiving characteristics of the power grid before and after the voltage adjustment and the power generation characteristics of the power supply points of the various power generation types, deep learning is performed to assist in monitoring the stability of the power grid; after the frequency adjustment is performed based on the frequency multi-round adjustment scheme, the method also includes: based on the power receiving characteristics of the power grid before and after the frequency adjustment and the power generation characteristics of the power supply points of the various power generation types, deep learning is performed to assist in monitoring the stability of the power grid.

[0122] Figure 6 A power dispatch signaling diagram in a large-machine and small-grid power system provided in an embodiment of the present application.

[0123] In view of the large-scale machine and small-grid working condition, the power grid requires that each type of power source be equipped with sufficient emergency backup capacity to achieve dispatching. The key to solving the power grid dispatching problem is the characteristics of various types of power sources in terms of frequency, power, and voltage stability under the large-scale machine and small-grid working condition, and the functional characteristics of various power plants under this condition are summarized to the grid-side dispatching center. The characteristics are as follows: nuclear power characteristics: infrequent power adjustment at low power; new energy dispatching characteristics: seasonal dispatching and day-ahead dispatching, reactive power regulation; pumped storage characteristics: restore system frequency; thermal power dispatching characteristics: suppress frequency drop.

[0124] The power grid uses frequency, voltage and power regulation as three multi-round adjustment factors. The first three are mid-level control production factors, reflecting the main characteristics of the power grid, and the power further requires the stability of the K value. The frequency change rate is affected differently by the various types of power sources called.

[0125] Various types of power plants first feedback their characteristics to the power grid according to power, frequency, and voltage. The power grid performs multiple rounds of adjustments of the first voltage and the second frequency according to the situation. The power grid performs energy storage dispatching, and at the same time, performs deep learning based on the power grid dispatching strategy library to obtain the correspondence between the initial selected measured and sample data. The corresponding power plant performance status is reported to the power grid, and the power grid records its applied electricity price and electricity, and then proceeds to the next step of adjusting the K value. The power grid calculates the appropriate and stable K value after adjustment, and determines the power plant's 24-hour output curve every day based on the K value and the frequency and load forecast of the entire network. With multiple rounds of voltage and frequency adjustments, the power grid assigns power curves to power plants. The power grid dispatches load curve instructions to various types of power plants and performs the third power adjustment. The power plant tracks the curve and adjusts power generation according to different loads. Finally, the generator operates to generate electricity, and it ends.

[0126] Through the analysis and research of the current grid structure and status of a certain power grid, the safe and stable operation technology of "large machine and small network" is deeply discussed, and the route to achieve the goal is proposed. Special simulation calculations on grid frequency stability, power angle stability, voltage stability, as well as primary and secondary frequency regulation, peak regulation strategy and energy storage solutions are carried out:

[0127] 1. Frequency stability problem: The most prominent and critical problem of "large generators and small grids" is the grid frequency problem. The total capacity of a certain country's grid is about 3977MW. The project will build two 350MW supercritical coal-fired power generating units, which account for a high proportion of the country's grid installed capacity. Once the unit trips, it will cause a sharp drop in the grid frequency. If no special measures are taken, the grid frequency will drop below 48.9 Hz at different times. If a certain grid has arranged low-frequency load reduction, it will take 1 to 3 rounds to remove 370 to 800MW of load, causing serious power supply safety problems for the grid; if a certain grid does not arrange reasonable low-frequency load reduction measures, the grid frequency faces the risk of collapse.

[0128] 2. Power angle stability and voltage stability issues: If a certain power grid has strengthened the construction of the main grid and the improvement of related equipment in recent years, the power angle stability level of the entire power grid will be relatively high. Under normal operation, the transient stability level depends on whether the fault can be quickly removed. As long as the rapid protection operates correctly, the transient stability level can meet the grid stability requirements of not losing load when a single fault of a three-phase short circuit occurs in the power grid. If the rapid protection fails to operate or the switch fails to operate, the power grid will still have transient stability problems. After a certain project is connected to the power grid, the grid stability level has not undergone a qualitative change. As long as a certain unit becomes the unit that is most easily removed in most unstable fault modes, and its loss of step will cause other units in the power grid to lose step in some fault modes, accompanied by voltage and frequency swings. The power angle stability level of a certain power grid is relatively poor. Under normal operation, the transient stability level is quickly removed after the fault, and the power grid still has power angle problems. After quickly removing a certain out-of-step unit, the grid voltage may not be able to recover to above 0.8pu, which will lead to voltage stability problems, and the power grid will face collapse, which may cause large-scale power outages.

[0129] In addition, the demagnetization of large units is usually unbearable for small power grids. Demagnetization of general power plant units is accompanied by loss of step, and the units of a certain project are no exception. Once a unit loses magnetism in an open circuit for about 1.08 seconds, it will lose step. If the demagnetization of the unit is removed within 1 second, stability can be maintained. If the demagnetization is not removed within 1 second, the power grid will also lose stability, bringing a series of consequences. When a unit loses magnetism, it absorbs a large amount of reactive power from the power grid, which will inevitably lead to a sharp drop in voltage, which is also unbearable for a certain power grid.

[0130] This problem needs to be solved. Reactive power needs to be provided at an extremely fast speed in the power grid. At the same time, the increase and decrease of reactive power needs to be coordinated. The reactive power needs to be made to correspond to the increase and decrease of reactive power when large units lose magnetism at a faster speed. A digital power coordination mechanism is needed to provide reactive power compensation for new energy photovoltaic power plants at the lowest cost. Thermal power can also provide reactive power relatively quickly, but attention needs to be paid to its safety and stability, such as coil heating.

[0131] To this end, this application identifies the problems existing in the grid-connected units and grid dispatching, sets up a series of effective safety automatic control strategies and primary and secondary frequency and peak regulation strategies for power plants, proposes a series of effective measures to ensure the safe operation of power plants, and at the same time puts forward some suggestions to ensure the safe and stable operation of a certain power grid and suggestions for strengthening the construction of a certain main grid as well as energy storage solutions, thereby improving the power generation utilization hours of a certain power plant and the safe operation capacity of the power grid.

[0132] The pumped storage unit reacts to the large-machine-small-grid dispatch as follows: For power grids with smaller system capacity, the AGC adjustment of power plants in the grid is slow. If the power of the pumped storage unit changes rapidly during startup and shutdown, the maximum value of the grid frequency fluctuation will exceed ±0.10 Hz. In order to avoid high-frequency machine shedding caused by frequency fluctuations, the speed governor parameters are adjusted to adjust the load increase time of the unit pumping condition startup from 25s to 59s, and the load reduction time of the unit pumping condition shutdown (-205 MW→0 MW) is adjusted from 11s to 44s. The test results show that after the parameters are optimized, the short-term fluctuation of the grid frequency caused by the startup and shutdown process of the pumped storage unit pumping condition is less than ±0.03 Hz, which meets the frequency requirements of the grid system. The load rise and fall time of the unit pumping condition startup and shutdown process is appropriately extended. During this process, the vibration swing value of each part of the unit does not increase significantly, and it can avoid passing through the vibration zone quickly, meeting the safe operation requirements of the unit.

[0133] The nuclear power unit can be disconnected from the power grid by tripping the steam turbine, tripping the generator outlet circuit breaker and demagnetizing, or directly throwing off the island operation mode according to different fault types. Among them, the main valve is closed first when the steam turbine is tripped, and then the generator outlet circuit breaker is tripped and demagnetized after the positive low-power protection is activated. Compared with directly tripping the generator outlet circuit breaker and demagnetizing, the damage to the generator outlet circuit breaker is less. The island operation, that is, the main transformer high-side circuit breaker is directly tripped and disconnected from the power grid during full power operation, and the generator runs with the unit's plant power. The disconnection speed is fast and the reactor can be stopped without stopping.

[0134] The coordinated photovoltaic dispatching logic of new energy photovoltaics for reactive power regulation focuses on photovoltaic day-ahead optimization dispatching and photovoltaic reactive power control. In order to solve the power imbalance problem of large-scale photovoltaic access to the "large machine and small grid" system, the loss cost of photovoltaic unabsorbed volume is considered in the day-ahead dispatching stage to improve the phenomenon of abandoned light, and the load curve is made smoother by introducing the demand-side response mechanism, which improves the economic operation of the "large machine and small grid" system. In the intraday dispatching stage, the multi-scenario prediction error of photovoltaic forecasting is considered, and the savings are flexibly adjusted to ensure a good tracking effect when photovoltaic fluctuations are severe.

[0135] The following points are recommended for power grid dispatching under large-scale power generation and small-scale network:

[0136] (1) Within a certain period of time before the unit is about to be put into operation, the power plant shall submit various parameters and information related to the system, such as the unit's high- and low-frequency trip protection settings, the transfer function block diagram of the excitation system and PSS, the PQ curve, the speed regulator parameters, etc. (2) Issue the settings of the excitation system and the speed control system to the power plant, and confirm whether the unit's demagnetization protection, loss of step protection, high-frequency, and low-frequency trip protection settings meet the system requirements. (3) Conduct a survey of the high- and low-frequency trip protection settings of large thermal power plants in the entire system. (4) Conduct spot checks on the correct commissioning and operation of various relay protection, low-frequency load reduction, and low-voltage load reduction equipment. (5) Organize the implementation of the black start plan, low-frequency power supply protection measures, and low-frequency self-starting devices of each hydropower and thermal power plant.

[0137] The embodiment of the present application also provides a power grid dispatching device in a large-machine small-grid power system. Figure 7 A schematic diagram of the structure of a power dispatching device in a large-scale small-grid power system provided in an embodiment of the present application. Figure 7 As shown, the device comprises:

[0138] The capacity configuration module 701 is used to determine the emergency reserve capacity of various power generation types that should be reserved in the power system and configure the emergency reserve capacity based on the digital feature extraction of the power grid and power source points of various power generation types in the power system;

[0139] The working condition judgment module 702 is used to judge whether the current power system meets the large-machine-small-grid feature based on the output of the power source points of the multiple power generation types;

[0140] The adjustment module 703 is used for, if it is determined by the working condition judgment module that the current power system meets the characteristics of large machine and small grid, the power grid uses the configured emergency reserve capacity of multiple power generation types to schedule the power source points in the power system for voltage adjustment based on the voltage multi-round adjustment scheme, and / or schedules the power source points in the power system for frequency adjustment based on the frequency multi-round adjustment scheme; the voltage multi-round adjustment scheme includes: the voltage multi-round adjustment mode, the voltage multi-round adjustment range and the voltage multi-round adjustment priority information for the multiple power generation types; the frequency multi-round adjustment scheme includes: the frequency multi-round adjustment mode, the frequency multi-round adjustment range and the frequency multi-round adjustment priority information for the multiple power generation types;

[0141] The output curve generation module 704 is used for generating the output curve of the units at each power source point in the future period of the power grid based on the stability control requirements of the frequency dynamic characteristic index of the whole network of the power system, the estimated load of the whole network and the characteristics of the units at each power source point; the frequency dynamic characteristic index is used to numerically represent the power change of the whole network required to cause the unit frequency change of the power system;

[0142] The dispatching instruction sending module 705 is used for the power grid to send power generation dispatching instructions to each power source point to adjust the power; the power generation dispatching instructions include the output curve of the unit of the corresponding power source point.

[0143] Optionally, the voltage multi-round adjustment range includes: photovoltaic, hydropower, nuclear power, thermal power and energy storage; the voltage multi-round adjustment priority information includes: photovoltaic>hydropower>nuclear power>thermal power>energy storage;

[0144] The multiple rounds of voltage adjustments include: four basic rounds of voltage adjustments corresponding to photovoltaic, hydropower, nuclear power and thermal power, and one accident round of voltage adjustments corresponding to fault conditions;

[0145] The voltage multi-round adjustment method includes: the action voltage and delay of the first basic round, the action voltage difference and delay of the remaining basic rounds, and the action voltage and delay of the accident round.

[0146] Optionally, the action voltage of the first basic wheel is 0.84pu, and the delay is 15-20s;

[0147] The action voltage difference of the remaining basic wheels is 0.01pu, and the delay is 0.2s;

[0148] The operating voltage of the accident wheel is 0.8pu and the delay is 0.1s.

[0149] Optionally, the adjustment module 703 is specifically configured to:

[0150] If the voltage of the power system is as low as 0.84 pu, the voltage adjustment corresponding to the first basic round of photovoltaic is started and lasts for 15 to 20 seconds; during the voltage adjustment of the first basic round, a part of the photovoltaic emergency reserve capacity is injected into the power grid;

[0151] If the voltage adjustment effect of the first basic round does not achieve the expected effect, when the voltage of the power system drops to 0.83pu, the second basic round of voltage adjustment corresponding to the hydropower is started and lasts for 0.2s; during the voltage adjustment period of the second basic round, a part of the emergency reserve capacity of the hydropower is injected into the power grid;

[0152] If the voltage adjustment effect of the second basic round does not achieve the expected effect, when the voltage of the power system drops to 0.82pu, the third basic round of voltage adjustment corresponding to the nuclear power is started and lasts for 0.2s; during the voltage adjustment period of the third basic round, a part of the emergency reserve capacity of the nuclear power is injected into the power grid;

[0153] If the voltage adjustment effect of the third basic round does not achieve the expected effect, when the voltage of the power system drops to 0.81pu, the fourth basic round of voltage adjustment corresponding to thermal power is started and lasts for 0.2s; during the fourth basic round of voltage adjustment, a part of the emergency reserve capacity of thermal power is injected into the power grid;

[0154] If the voltage adjustment effect of the fourth basic round fails to achieve the expected effect, and the voltage of the power system is monitored to be as low as 0.8pu, the voltage adjustment of the accident round is started, the load is cut off or the energy storage system is started; during the voltage adjustment of the accident round, all or part of the remaining accident reserve capacity of each power generation type is injected into the power grid.

[0155] Optionally, the frequency multi-round adjustment range includes: thermal power, hydropower, nuclear power and energy storage; the frequency multi-round adjustment priority information includes: thermal power>hydropower>nuclear power>energy storage;

[0156] The multiple rounds of frequency adjustments include: three basic rounds of frequency adjustments corresponding to thermal power, hydropower, and nuclear power, and one round of accident frequency adjustments corresponding to fault conditions;

[0157] The frequency multi-round adjustment method includes: the action frequency and delay of the first basic wheel, the action frequency difference and delay of the remaining basic wheels, and the action frequency and delay of the accident wheel.

[0158] Optionally, the action frequency of the first basic wheel is 49.8 Hz, with a delay of 0.2 s;

[0159] The action frequency difference of the remaining basic wheels is 0.2 Hz, and the delay is 0.2 s;

[0160] The operating frequency of the accident wheel is 49.2 Hz, with a delay of 0.1 s.

[0161] Optionally, the adjustment module 703 is specifically configured to:

[0162] If the frequency of the power system drops to 49.8 Hz, the frequency adjustment corresponding to the first basic round of thermal power is started and lasts for 0.2 s; during the first basic round of frequency adjustment, a portion of the emergency reserve capacity of the thermal power is injected into the power grid;

[0163] If the frequency adjustment effect of the first basic round does not achieve the expected effect, when the frequency of the power system drops to 49.6 Hz, the second basic round of frequency adjustment corresponding to the hydropower is started and lasts for 0.2 s; during the second basic round of frequency adjustment, a part of the emergency reserve capacity of the hydropower is injected into the power grid;

[0164] If the frequency adjustment effect of the second basic round does not achieve the expected effect, when the frequency of the power system drops to 49.4 Hz, the third basic round of frequency adjustment corresponding to the nuclear power is started and lasts for 0.2 s; during the third basic round of frequency adjustment, a part of the nuclear power emergency reserve capacity is injected into the power grid;

[0165] If the frequency adjustment effect of the third basic round does not achieve the expected effect, wait until the frequency of the power system drops to 49.2Hz, start the frequency adjustment of the accident round, cut off the load or start the energy storage system; during the frequency adjustment of the accident round, all or part of the remaining accident reserve capacity of each power generation type will be injected into the power grid.

[0166] Optionally, the device further comprises:

[0167] The reactive power compensation module is used to control the reactive power of some power supply points to compensate and adjust the voltage.

[0168] Optionally, the step of adjusting the frequency by the adjustment module 703 based on the frequency multi-round adjustment scheme is performed after the reactive power compensation module controls the reactive power of some power points to compensate and adjust the voltage and after frequency monitoring.

[0169] Optionally, the output curve generating module 704 is specifically configured to:

[0170] Determine the target value of the frequency dynamic characteristic index;

[0171] Based on the target value, the monitored frequency disturbance of the power system, the expected load of the entire network and the unit characteristics of each power source, the output curve of the units at each power source in the future period is generated, so as to control the power of each unit through the output curve, so that the deviation between the actual value of the frequency dynamic characteristic index and the target value is within the preset index floating range; the unit characteristics include the power change that the unit of the power source needs to provide for unit frequency change.

[0172] Optionally, the output curve generating module 704 is specifically configured to:

[0173] Based on the target value, the monitored frequency disturbance of the power system, and the unit characteristics of each power source point, determine the power change amount that should be provided by the power source point of each power generation type so that the deviation amount between the actual value of the frequency dynamic characteristic index and the target value is within a preset index floating range;

[0174] Based on the predicted total grid load in the future period and the power variation that the power sources of each type of power generation should provide, the output curve of the units at each power source in the future period is generated.

[0175] Optionally, the device further comprises: a deep learning module;

[0176] A deep learning module, configured to perform deep learning based on the power receiving characteristics of the power grid before and after the voltage adjustment and the power generation characteristics of the power supply points of the multiple power generation types after the voltage adjustment is performed based on the voltage multi-round adjustment scheme, so as to assist in monitoring the stability of the power grid;

[0177] The deep learning module is also used to perform deep learning based on the power receiving characteristics of the power grid before and after the frequency adjustment and the power generation characteristics of the power supply points of the multiple power generation types after the frequency adjustment is performed based on the multi-round frequency adjustment scheme, so as to assist in monitoring the stability of the power grid.

[0178] Optionally, the device also includes: a stability monitoring module, which is used to monitor the stability of the power grid in real time before judging whether the current power system meets the characteristics of large machine and small grid, so as to identify whether there is a risk of frequency or voltage drop in the power grid.

[0179] Optionally, the operating condition judgment module 702 is specifically used to:

[0180] If the sum of the outputs of any two units in any current power source of any type of power generation exceeds 15% of the total capacity of the current power system, the power system is judged to meet the characteristics of large units and small grids.

[0181] It should be noted that each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device embodiment described above is merely schematic, in which the unit described as a separate component may or may not be physically separated, and the component prompted as a unit may or may not be a physical unit, that is, it may be located in one place, or it may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.

[0182] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power grid dispatching method in a large-scale small-grid power system, characterized in that: include: Based on the extraction of digital features of the power grid and power supply points of various power generation types in the power system, the accident reserve capacity of various power generation types that should be reserved in the power system is determined and the accident reserve capacity is configured; wherein the accident reserve capacity of various power generation types is calculated after the digital features of the power grid and power supply points of each power generation type are extracted, the ability level of various types of power supply points in adjusting the voltage stability of the power system, the ability level of various types of power supply points in adjusting the frequency stability of the power system, and the frequency dynamic characteristics of each power supply point in different load periods are determined; Based on the output of the power source points of the multiple power generation types, judging whether the current power system meets the characteristics of large machine and small grid; If it is determined that the current power system meets the characteristics of large machines and small grids, the power grid utilizes the configured emergency reserve capacity of multiple power generation types, first dispatches the power supply points in the power system for voltage adjustment based on the voltage multi-round adjustment plan, and then dispatches the power supply points in the power system for frequency adjustment based on the frequency multi-round adjustment plan; the voltage multi-round adjustment plan includes: voltage multi-round adjustment methods, voltage multi-round adjustment ranges and voltage multi-round adjustment priority information for the multiple power generation types; the voltage multi-round adjustment range includes: photovoltaic, hydropower, nuclear power, thermal power and energy storage; the frequency multi-round adjustment plan includes: frequency multi-round adjustment methods, frequency multi-round adjustment ranges and frequency multi-round adjustment priority information for the multiple power generation types; the frequency multi-round adjustment range includes: thermal power, hydropower, nuclear power and energy storage; Based on the stability control requirements of the frequency dynamic characteristic index of the whole network of the power system, the expected load of the whole network and the characteristics of the units of each power source point, the power grid generates the output curve of the units of each power source point in the future period; the frequency dynamic characteristic index is used to numerically characterize the power change of the whole network required to cause the unit frequency change of the power system; The power grid sends a power generation dispatching instruction to each power source point to adjust the power; the power generation dispatching instruction includes an output curve of the unit of the corresponding power source point; Based on the stability control requirements of the frequency dynamic characteristic index of the whole network of the power system, the estimated whole network load and the characteristics of the units of each power source point, the power grid generates the output curve of the units of each power source point in the future period, including: Determine the target value of the frequency dynamic characteristic index; Based on the target value, the monitored frequency disturbance of the power system, and the unit characteristics of each power source point, determine the power change amount that the power source point of each power generation type should provide so that the deviation amount between the actual value of the frequency dynamic characteristic index and the target value is within a preset index floating range; According to the predicted total grid load in the future period and the power variation that the power source points of each power generation type should provide, the output curve of the units of each power source point in the future period is generated, so as to control the power of each unit through the output curve, so that the deviation between the actual value of the frequency dynamic characteristic index and the target value is within the preset index floating range; the unit characteristics include the power variation that the unit of the power source point needs to provide for the unit frequency change; The voltage multi-round adjustment priority information includes: photovoltaic power>hydropower>nuclear power>thermal power>energy storage; The multiple rounds of voltage adjustments include: four basic rounds of voltage adjustments corresponding to photovoltaic, hydropower, nuclear power and thermal power, and one accident round of voltage adjustments corresponding to fault conditions; The voltage multi-round adjustment method includes: the action voltage and delay of the first basic round, the action voltage difference and delay of the remaining basic rounds, and the action voltage and delay of the accident round; The frequency multi-round adjustment priority information includes: thermal power>hydropower>nuclear power>energy storage; The multiple rounds of frequency adjustments include: three basic rounds of frequency adjustments corresponding to thermal power, hydropower, and nuclear power, and one round of accident frequency adjustments corresponding to fault conditions; The frequency multi-round adjustment method includes: the action frequency and delay of the first basic wheel, the action frequency difference and delay of the remaining basic wheels, and the action frequency and delay of the accident wheel.

2. The method according to claim 1, characterized in that The action voltage of the first basic wheel is 0.84pu, with a delay of 15-20s; The action voltage difference of the remaining basic wheels is 0.01pu, and the delay is 0.2s; The operating voltage of the accident wheel is 0.8pu and the delay is 0.1s.

3. The method according to claim 1, characterized in that Utilize the emergency reserve capacity of various types of power generation that have been configured to adjust the voltage based on the multi-round voltage adjustment scheme, including: If the voltage of the power system is as low as 0.84 pu, the voltage adjustment corresponding to the first basic round of photovoltaic power generation is started and lasts for 15 to 20 seconds; during the voltage adjustment of the first basic round, a part of the photovoltaic power generation emergency reserve capacity is injected into the power grid; If the voltage adjustment effect of the first basic round does not achieve the expected effect, when the voltage of the power system drops to 0.83pu, the second basic round of voltage adjustment corresponding to the hydropower is started and lasts for 0.2s; during the voltage adjustment period of the second basic round, a part of the emergency reserve capacity of the hydropower is injected into the power grid; If the voltage adjustment effect of the second basic round does not achieve the expected effect, when the voltage of the power system drops to 0.82pu, the third basic round of voltage adjustment corresponding to the nuclear power is started and lasts for 0.2s; during the voltage adjustment period of the third basic round, a part of the emergency reserve capacity of the nuclear power is injected into the power grid; If the voltage adjustment effect of the third basic round does not achieve the expected effect, when the voltage of the power system drops to 0.81pu, the fourth basic round of voltage adjustment corresponding to thermal power is started and lasts for 0.2s; during the fourth basic round of voltage adjustment, a part of the emergency reserve capacity of thermal power is injected into the power grid; If the voltage adjustment effect of the fourth basic round fails to achieve the expected effect, and the voltage of the power system is monitored to be as low as 0.8pu, the voltage adjustment of the accident round is started, the load is cut off or the energy storage system is started; during the voltage adjustment of the accident round, all or part of the remaining accident reserve capacity of each power generation type is injected into the power grid.

4. The method according to claim 1, characterized in that: The action frequency of the first basic wheel is 49.8 Hz, with a delay of 0.2 s; The action frequency difference of the remaining basic wheels is 0.2 Hz, and the delay is 0.2 s; The operating frequency of the accident wheel is 49.2 Hz, with a delay of 0.1 s.

5. The method according to claim 4, characterized in that Utilize the configured emergency reserve capacity of various power generation types to adjust the frequency based on the frequency multi-round adjustment scheme, including: If the frequency of the power system drops to 49.8 Hz, the frequency adjustment corresponding to the first basic round of thermal power is started and lasts for 0.2 s; during the first basic round of frequency adjustment, a portion of the emergency reserve capacity of the thermal power is injected into the power grid; If the frequency adjustment effect of the first basic round does not achieve the expected effect, when the frequency of the power system drops to 49.6 Hz, the second basic round of frequency adjustment corresponding to the hydropower is started and lasts for 0.2 s; during the second basic round of frequency adjustment, a part of the emergency reserve capacity of the hydropower is injected into the power grid; If the frequency adjustment effect of the second basic round does not achieve the expected effect, when the frequency of the power system drops to 49.4 Hz, the third basic round of frequency adjustment corresponding to the nuclear power is started and lasts for 0.2 s; during the third basic round of frequency adjustment, a part of the nuclear power emergency reserve capacity is injected into the power grid; If the frequency adjustment effect of the third basic round does not achieve the expected effect, wait until the frequency of the power system drops to 49.2Hz, start the frequency adjustment of the accident round, cut off the load or start the energy storage system; during the frequency adjustment of the accident round, all or part of the remaining accident reserve capacity of each power generation type will be injected into the power grid.

6. The method according to claim 1, characterized in that After the voltage is adjusted based on the voltage multi-round adjustment scheme, the method further includes: The power grid controls the reactive power of some power supply points to compensate and adjust the voltage.

7. The method according to claim 6, characterized in that The step of adjusting the frequency based on the frequency multi-round adjustment scheme is performed after the step of compensating and adjusting the voltage by controlling the reactive power of the power supply points of the power grid and after frequency monitoring.

8. The method according to any one of claims 1 to 7, characterized in that After the voltage is adjusted based on the voltage multi-round adjustment scheme, the method further includes: Performing deep learning based on the power receiving characteristics of the power grid before and after voltage adjustment and the power generation characteristics of the power supply points of the multiple power generation types to assist in monitoring the stability of the power grid; After the frequency adjustment is performed based on the frequency multi-round adjustment scheme, the method further includes: Deep learning is performed based on the power receiving characteristics of the power grid before and after frequency adjustment and the power generation characteristics of the power supply points of the multiple power generation types to assist in monitoring the stability of the power grid.

9. The method according to any one of claims 1 to 7, characterized in that: Before determining whether the current power system meets the large-machine-small-grid feature, the method further includes: The stability of the power grid is monitored in real time to identify whether the power grid has a risk of frequency or voltage drop.

10. The method according to any one of claims 1 to 7, characterized in that The determining, based on the outputs of the power supply points of the multiple power generation types, whether the current power system meets the large-machine-small-grid feature includes: If the sum of the outputs of any two units in any current power source of any type of power generation exceeds 15% of the total capacity of the current power system, the power system is judged to meet the characteristics of large units and small grids.

11. A power grid dispatching device in a large-scale small-grid power system, characterized in that: include: A capacity configuration module is used to determine the emergency reserve capacity of various power generation types that should be reserved in the power system and configure the emergency reserve capacity based on the digital feature extraction of the power grid and power source points of various power generation types in the power system; wherein the emergency reserve capacity of various power generation types is calculated based on the extraction of the digital features of the power grid and power source points of various power generation types, and the ability level of various types of power source points in adjusting the voltage stability of the power system, the ability level of various types of power source points in adjusting the frequency stability of the power system, and the frequency dynamic characteristics of each power source point in different load periods; A working condition judgment module, used to judge whether the current power system meets the characteristics of large machine and small grid based on the output of the power source points of the current multiple power generation types; an adjustment module, for, if it is determined by the working condition judgment module that the current power system meets the characteristics of large machine and small grid, the power grid utilizes the configured emergency reserve capacity of multiple power generation types, first dispatches the power supply points in the power system for voltage adjustment based on the voltage multi-round adjustment scheme, and then dispatches the power supply points in the power system for frequency adjustment based on the frequency multi-round adjustment scheme; the voltage multi-round adjustment scheme includes: voltage multi-round adjustment mode, voltage multi-round adjustment range and voltage multi-round adjustment priority information for the multiple power generation types; the voltage multi-round adjustment range includes: photovoltaic, hydropower, nuclear power, thermal power and energy storage; the frequency multi-round adjustment scheme includes: frequency multi-round adjustment mode, frequency multi-round adjustment range and frequency multi-round adjustment priority information for the multiple power generation types; the frequency multi-round adjustment range includes: thermal power, hydropower, nuclear power and energy storage; An output curve generation module is used for generating output curves of the units at each power source point in the future period of the power grid based on the stability control requirements of the frequency dynamic characteristic index of the whole network of the power system, the estimated load of the whole network and the characteristics of the units at each power source point; the frequency dynamic characteristic index is used to numerically characterize the power change of the whole network required to cause the unit frequency change of the power system; A dispatching instruction sending module is used for the power grid to send power dispatching instructions to each power source point to adjust the power; the power dispatching instruction includes an output curve of the unit of the corresponding power source point; The output curve generating module is specifically used for: Determine the target value of the frequency dynamic characteristic index; Based on the target value, the monitored frequency disturbance of the power system, and the unit characteristics of each power source point, determine the power change amount that the power source point of each power generation type should provide so that the deviation amount between the actual value of the frequency dynamic characteristic index and the target value is within a preset index floating range; According to the predicted total grid load in the future period and the power variation that the power source points of each power generation type should provide, the output curve of the units of each power source point in the future period is generated, so as to control the power of each unit through the output curve, so that the deviation between the actual value of the frequency dynamic characteristic index and the target value is within the preset index floating range; the unit characteristics include the power variation that the unit of the power source point needs to provide for the unit frequency change; The voltage multi-round adjustment priority information includes: photovoltaic power>hydropower>nuclear power>thermal power>energy storage; The multiple rounds of voltage adjustments include: four basic rounds of voltage adjustments corresponding to photovoltaic, hydropower, nuclear power and thermal power, and one accident round of voltage adjustments corresponding to fault conditions; The voltage multi-round adjustment method includes: the action voltage and delay of the first basic round, the action voltage difference and delay of the remaining basic rounds, and the action voltage and delay of the accident round; The frequency multi-round adjustment priority information includes: thermal power>hydropower>nuclear power>energy storage; The multiple rounds of frequency adjustments include: three basic rounds of frequency adjustments corresponding to thermal power, hydropower, and nuclear power, and one round of accident frequency adjustments corresponding to fault conditions; The frequency multi-round adjustment method includes: the action frequency and delay of the first basic wheel, the action frequency difference and delay of the remaining basic wheels, and the action frequency and delay of the accident wheel.

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