Control method for avoiding system load oscillation caused by new energy electric power fluctuation through intelligent start and stop of hydroelectric generating set

Abstract

The invention discloses a control method for avoiding system load oscillation caused by new energy electric power fluctuation by utilizing intelligent start and stop of a hydroelectric generating set, which calls hydroelectric spinning reserve capacity and timely stops to provide enough adjustable lower limit so as to improve hydroelectric adjustable capability and provide maximum support for system frequency stability. The adjustable hydropower station has a unit intelligent start-stop function, can realize full automatic start-stop control according to a system load, and can automatically start a standby unit to provide more spinning reserve capacity when the generated output of a grid-connected unit of the hydropower station reaches the maximum output upper limit under the current water head or approaches the maximum output upper limit; when the output of the grid-connected units of the hydropower station reaches or approaches to the minimum technical output lower limit, the grid-connected units of the hydropower station can automatically penetrate through the vibration area to execute shutdown operation, and more load down-regulation space is provided, so that reliable guarantee is provided for the stability of a power system, and system oscillation caused by new energy power fluctuation is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of hydropower and renewable energy power complementary regulation, and in particular to a control method for utilizing the intelligent start and stop of hydropower units to avoid system load oscillation caused by renewable energy power fluctuations. Background Art

[0002] 1. AGC is the abbreviation of Automatic Generation Control. It is based on the set values ​​issued by the dispatching, centralized control, power plant and other regulating sources, or the regulating instructions given by the outside, and after necessary logical operations, it is assigned to the generating value of the generator group. The generator group adjusts the power output at a certain regulating rate to meet the service requirements of the power system frequency and tie line power control. For dispatching, it has the function of issuing the regulating instruction of the active setting value according to the load demand of the power system; for centralized control or a single power plant, it has the functions of investing in single-machine AGC, investing in the whole plant AGC, investing in the closed-loop control of the whole plant AGC, switching the regulating source, and executing the regulating instructions issued by dispatching.

[0003] 2. There are currently a variety of strategies for the intelligent start and stop of hydropower units. In order to meet the needs of matching the fluctuation of new energy power load and ensure the stability of the load and frequency of the power system, the situation awareness mode is used to implement the intelligent start and stop control strategy of hydropower units. According to the actual situation, the AGC regulation source of the whole hydropower station is dispatching in most cases, so the specific perception objects are: the active setting value issued by the dispatching, the actual value of the active output of new energy power, the actual active output value of the power plant, the maximum technical output of the power plant, the minimum technical output of the power plant, the guide vane opening, etc. By perceiving the corresponding load setting requirements and the relevant parameters of the power plant, the standby units are started in advance, or the rotating standby capacity is increased by timely passing through the vibration zone to prevent the system impact caused by the volatility of new energy power, so as to ensure the stability of the load and frequency of the power system.

[0004] 3. Secondary frequency regulation: In the power system, electricity is used immediately after it is generated, and electricity cannot be stored. Even the energy storage power stations and energy storage devices in the current power system actually store a very small proportion of electricity, and they are regional. In this case, there must be a balance between power generation and power consumption in the power system. When the power generation is higher than the power consumption, the power system shows an increase in frequency. When the power generation is lower than the power consumption, the power system shows a decrease in frequency. Therefore, the key to the stability of the power system lies in the stability of the frequency. In my country, the rated frequency of the power system is 50Hz. In fact, in actual use, there is no absolute 50Hz frequency balance. As long as the frequency can be controlled within the range of allowable fluctuations, it is considered a system balance. According to the standards of the Southern Power Grid, for hydropower, the frequency is controlled within the range of 50±0.1Hz to meet the system requirements. When the system frequency is high, the dispatcher issues a command to reduce the active load and reduce the power generation output of the power generation end to reduce the system frequency. When the system frequency is low, the dispatcher issues a command to increase the active load and increase the power generation output of the power generation end to increase the system frequency so that the system frequency is maintained within the standard range.

[0005] 4. Primary frequency regulation: It is one of the basic functions that grid-connected power generation units must have. It can automatically adjust the power generation output of the generator set according to the system frequency. Of course, the adjustment amount of primary frequency regulation is limited. When the primary frequency regulation still cannot meet the system frequency requirements, the manual setting control method of secondary frequency regulation is adopted to ensure the stability of the power system frequency. Primary frequency regulation refers to the control method in which the generator set automatically responds and adjusts to increase or reduce part of the active load to stabilize the system frequency when the power system frequency reaches the set threshold value within the standard range. For example, in the access conditions of the hydropower units of the Southern Power Grid, 50±0.06Hz is the frequency difference limit of the primary frequency regulation of the hydropower unit. When the system frequency reaches the boundary of 50+0.06Hz, the primary frequency regulation will increase the active power of the unit based on the original set value of the unit; when the system frequency reaches the boundary of 50-0.06Hz, the primary frequency regulation will reduce the active power of the unit based on the original set value of the unit; through the above methods, the system frequency is automatically stabilized. Of course, not every generator set can guarantee the correct operation of a frequency regulation. Even if it does, it cannot guarantee that the integrated power of a frequency regulation action meets the design standard, because there are constraints from the unit's own characteristics such as the dead zone of the speed regulator action and the response time.

[0006] 5. Low-frequency oscillation of power system: With the improvement of power system technology, the excitation system gradually adopts voltage deviation proportional regulation. Under high magnification, the voltage response speed increases, and the excitation system has inertia. The power system shows a lack of damping or negative damping torque, which causes power fluctuations on the transmission line. The frequency is generally between 0.1Hz and 2.0Hz, which is called low-frequency oscillation, also known as power oscillation and electromechanical oscillation. For generators, it is mainly manifested in the relative swing between the generator rotors. In general, after the power system is disturbed, low-frequency oscillation appears on weakly connected, long-distance, and heavy-load transmission lines, usually caused by the following disturbances: ① machine shedding, ② transmission line failure, ③ protection malfunction, ④ circuit breaker equipment failure, ⑤ loss of load, etc.

[0007] 6. The instability and intermittency of new energy sources mainly depend on natural factors. Photovoltaic power generation is a key factor in terms of light intensity and angle. Generally, the efficiency of direct sunlight at noon is the highest, followed by morning and afternoon, and the power generation at night is 0. The output power of photovoltaic power generation is generally a parabola, and its conventional characteristics are intermittent, unstable, and unadjustable day and night. In order to improve the efficiency of photovoltaic power generation, the photovoltaic panels of a single photovoltaic power generation unit in China generally have the characteristics of automatically adjusting the angle to adapt to the angle of light. In this case, the angle of light can be automatically optimized, but there is still an adjustable angle range for photovoltaic power generation units, which still has an impact after exceeding the range. In addition, for photovoltaic power generation, weather factors such as cloudy days, rain, and sometimes sunny days will cause the volatility of photovoltaic power generation. Similarly, wind power generation is more dependent on wind speed and direction. Like photovoltaic units, wind turbines also have blade self-rotation devices and other devices that can automatically adjust the generator to the most efficient position, but the wind itself is volatile and intermittent, which also causes the output power of wind power generation to be volatile and intermittent.

[0008] 7. As the country vigorously promotes the development of clean energy and improves the green and low-carbon transformation of energy, the development of new energy and electricity has made rapid progress in recent years. At present, the fastest-growing and highest-proportion new energy are photovoltaic power generation and wind power generation. Both photovoltaic and wind power are closely related to the weather, and both have unstable power generation, unadjustable or less adjustable. Combined with the above-mentioned power system characteristics, to maintain the stability of the system frequency, a more flexible, adjustable and controllable power supply must be matched with it. Looking at the composition of China's power structure, according to statistics from the National Energy Administration and the China Electricity Council, by the end of 2023, calculated by installed capacity, thermal power accounts for 47.6%, hydropower accounts for 14.4%, photovoltaic accounts for 20.9%, wind power accounts for 15.1%, nuclear power accounts for 1.9%, and other energy storage power stations account for a negligible proportion. With wind power and photovoltaic power accounting for up to 36%, their instability and intermittency further aggravate the oscillation of the power system frequency. If a power system accident occurs, it may cause a large-scale power system accident. Thermal power and nuclear power have small regulation capabilities, long regulation cycles, and insufficient flexibility. In order to ensure the stability of the power system, the complementary regulation of hydropower, which accounts for 14.4%, is particularly important. In the management regulations of the Southern Power Grid, the requirement for the active power change rate of photovoltaic and wind power as the main new energy is 10% of the installed capacity, while the requirement for the active power change rate of hydropower is 20%, which means that the regulation rate of hydropower should be twice that of new energy, which further demonstrates the flexibility of hydropower. Among the 14.1% of hydropower, there are small hydropower stations that have almost no regulation capabilities, and some special ones such as Jinghong Hydropower Station, which belongs to the last hydropower station in the Lancang River Basin, bears the responsibility of joint patrol law enforcement to stabilize the flow, and considering the international environment, it is not suitable for large flow changes. It has been operating at almost fixed load for many years, and the regulation capacity is limited. That is to say, the current proportion of adjustable hydropower is about 10%, but in the southern region rich in hydropower, the flexible regulation performance of hydropower is very obvious for the matching effect of new energy.

[0009] Based on the above analysis, in order to avoid the impact of the instability and intermittency of renewable energy on the power system, from the perspective of the proportion and adjustability of China's power structure, in addition to energy storage power stations, which currently account for an almost negligible proportion, hydropower is the most suitable power source for complementary matching of renewable energy. However, it is impossible for hydropower and renewable energy to achieve a 100% match. The most critical issue is that the instability of renewable energy may cause load oscillation in the power system. Even if hydropower is flexibly adjusted, it still has an adjustable boundary. When the system load volatility reaches the hydropower matching boundary, there is still a risk of system frequency oscillation. Summary of the invention

[0010] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0011] To this end, the present invention proposes a control method for avoiding system load oscillation caused by renewable energy power fluctuations by using the intelligent start and stop of hydropower units. When renewable energy power load fluctuations occur due to weather factors, natural laws, etc., and the system load adjustment boundary is limited, the cross-section of the system transmission line may be limited, resulting in load loss at the power supply end or the power receiving end, thereby causing low-frequency oscillation of the power system. By making full use of the flexibility of hydropower, the standby units are started in advance through situation awareness, and the redundant units are stopped in time, thereby increasing the system load adjustment space, thereby avoiding the oscillation risk caused by renewable energy load fluctuations.

[0012] To achieve the above-mentioned purpose, the present invention proposes a control method for using intelligent start and stop of hydropower units to avoid system load oscillation caused by fluctuations in renewable energy power, comprising:

[0013] The regional photovoltaic power station output power calculation module is used to calculate the total grid-connected output power of each photovoltaic power station, the regional wind power plant output power calculation module is used to calculate the total grid-connected output power of each wind power plant, the regional hydropower station adjustable power calculation module with regulation capability is used to calculate the adjustable power of each hydropower station, the regional other non-adjustable power supply output power calculation module is used to calculate the output power of all non-adjustable power supplies, the regional interconnection line transmission power calculation module is used to calculate the total output power of the interconnection line, and the regional receiving end power calculation module is used to calculate all receiving end powers;

[0014] The logic operation control module of regional integrated power source power is used to calculate the difference between the sum of the total grid-connected output power of each photovoltaic power station, the total grid-connected output power of each wind power plant and the adjustable power of each hydropower station and the output power of the non-adjustable power source, the total output power of the tie line, the receiving end power and the transmission loss power. When it is judged that the difference is not equal to zero, it is shown that the power system frequency changes. If the frequency change is within the preset range, the system stability requirement is met. When the system frequency exceeds the preset range, a frequency regulation action is triggered to pull the frequency back to this range. If the frequency regulation action cannot pull the frequency back, a load regulation instruction is sent to the hydropower with good regulation performance through the logic operation control module of regional integrated power source power.

[0015] An automatic start-stop strategy control module for the hydropower station is set up. The hydropower station receives and executes the load adjustment command, and the difference is close to zero until the system frequency is pulled back into the preset range. If the maximum adjustment amount of all hydropower stations with adjustment capabilities in the area cannot be satisfied to pull the frequency back into the stable range, the automatic start-stop strategy control module of the hydropower station is used to start and stop the hydropower units to change the boundary conditions of the hydropower output power.

[0016] The control method of the embodiment of the present invention using the intelligent start and stop of the hydropower unit to avoid the system load oscillation caused by the fluctuation of the new energy power may also have the following additional technical features:

[0017] In one embodiment of the present invention, the logic operation control module of the regional integrated power source power is used to receive active power data from photovoltaic, wind power, hydropower, thermal power, other power sources, tie lines, and receiving ends, and the input and output power sources are respectively summarized and calculated, and the photovoltaic input power is set as P g(i) , wind power input power is P f(i) , the hydropower input power is P s(i) , other power input power is P q(i) , the total input power in the area is P r =∑[P g(i) +P f(i) +P s(i) +P q(i) ]; Set the tie line power to P l(i) , the receiving end power is P y(i) , the total output power is P c =∑[P l(i) +P y(i) ].

[0018] In one embodiment of the present invention, the power of the photovoltaic power station is collected by the power collection modules of all photovoltaic power stations in the region, and the collected power is sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n photovoltaic power stations in the region, the total photovoltaic input power is:

[0019]

[0020] In one embodiment of the present invention, photovoltaic power is collected by power collection modules of all wind power stations in the region.

[0021] The power station power is collected and sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n wind power stations in this area, the total photovoltaic input power is:

[0022]

[0023] In one embodiment of the present invention, the safety boundary conditions from all hydropower stations in the region are received through the logic operation control module of the regional integrated power supply power, and screening is performed according to the safety boundary conditions. Power supplies that are non-adjustable and whose output power can be changed at any time are classified as first-category power supplies, other non-adjustable power supplies and power supplies with stable output power are classified as second-category power supplies, and power supplies with stable and adjustable output power but poor adjustable performance are classified as third-category power supplies.

[0024] In one embodiment of the present invention, the output power of each power supply without regulation capability is collected by the power collection module of the power supply without regulation capability in the area, and the collected output power of each power supply without regulation capability is sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n power supplies without regulation capability in the area, the total input power is:

[0025]

[0026] In one embodiment of the present invention, the transmission power of each tie line is collected by the tie line power collection module in the region, wherein the input is positive and the output is negative, and the collected transmission power of each tie line is sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n tie lines in this region, the total output power is:

[0027]

[0028] In one embodiment of the present invention, the receiving end power is collected by the regional receiving end power collection module, and the collected receiving end power is sent to the regional integrated power supply power logic operation control module. Assuming that there are n receiving ends in this area, the total output power is:

[0029]

[0030] In one embodiment of the present invention, node calculation is performed by a logic operation control module of regional integrated power supply power, that is, P r -P c =ΔP, when ΔP is positive, the system shows a frequency increase. When the rising frequency reaches 50+0.06Hz, the primary frequency modulation is triggered to adjust downward. When the primary frequency modulation action cannot pull the frequency back to less than 50+0.06Hz, the secondary frequency modulation is triggered. The logic operation control module of the regional integrated power supply power gives priority to sending load reduction instructions to the hydropower with good regulation performance until the frequency is reduced to less than 50+0.06Hz again; when ΔP is negative, the system frequency shows a decrease. When the decreasing frequency reaches 50-0.06Hz, the primary frequency modulation is triggered to adjust upward. When the primary frequency modulation action cannot pull the frequency back to more than 50-0.06Hz, the secondary frequency modulation is triggered. The logic operation control module of the regional integrated power supply power gives priority to sending load increase instructions to the hydropower with good regulation performance until the frequency is increased to more than 50-0.06Hz again.

[0031] In one embodiment of the present invention, the method further includes putting a hydropower station with regulation capability into plant-level AGC control. The hydropower station dispatches active power set values, AGC unit guide vane opening, minimum technical output lower limit, and maximum technical output upper limit through situation awareness detection, and determines startup or shutdown in advance to provide regulation space for the system regulation demand and meet the system regulation demand.

[0032] The control method of the embodiment of the present invention utilizes the intelligent start and stop of hydropower units to avoid system load oscillation caused by fluctuations in renewable energy power, and realizes fully automatic start and stop control according to the system load. When the power generation output of the grid-connected units of the hydropower station has reached the maximum output upper limit under the current water head or is close to the maximum output upper limit, the standby units can be automatically started to provide more rotating standby capacity; when the output of the grid-connected units of the hydropower station has reached or is close to the minimum technical output lower limit, they can automatically cross the vibration zone to perform shutdown operations, providing more load reduction space, thereby providing reliable protection for the stability of the power system and avoiding system oscillations caused by fluctuations in renewable energy power.

[0033] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0035] Figure 1 This is a flow chart of a control method for using intelligent start and stop of a water-generating unit to avoid system load oscillation caused by fluctuations in new energy power;

[0036] Figure 2 It is a trend chart of water, wind and solar power generation in a certain area of ​​the power grid of the present invention;

[0037] Figure 3 It is the main flow chart of the intelligent start and stop logic of the regional hydropower unit of the present invention;

[0038] Figure 4 A schematic diagram of the load flow of the regional power supply computing module of the present invention;

[0039] Figure 5 This is a preferred logical schematic diagram of the hydroelectric unit of the present invention. DETAILED DESCRIPTION

[0040] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0042] The following describes a control method for intelligently starting and stopping a water-generating unit to avoid system load oscillation caused by fluctuations in renewable energy power according to an embodiment of the present invention with reference to the accompanying drawings.

[0043] Figure 1 1 is a flow chart of a control method for intelligently starting and stopping a water-generating unit to avoid system load oscillation caused by fluctuations in renewable energy power according to an embodiment of the present invention. Figure 1 As shown, the method includes:

[0044] S1, respectively using the regional photovoltaic power station output power calculation module to calculate the total grid-connected output power of each photovoltaic power station, the regional wind power plant output power calculation module to calculate the total grid-connected output power of each wind power plant, the regional hydropower station adjustable power calculation module with regulation capability to calculate the adjustable power of each hydropower station, the regional other non-adjustable power supply output power calculation module to calculate all non-adjustable power supply output power, the regional interconnection line transmission power calculation module to calculate the total interconnection line output power and the regional receiving end power calculation module to calculate all receiving end powers;

[0045] S2, using the logic operation control module of the regional integrated power supply power to calculate the difference between the sum of the total grid-connected output power of each photovoltaic power station, the total grid-connected output power of each wind power plant and the adjustable power of each hydropower station and the output power of the non-adjustable power supply, the total output power of the interconnection line, the receiving end power and the transmission loss power. When it is determined that the difference is not equal to zero, it is shown that the power system frequency changes. If the frequency change is within the preset range, the system stability requirement is met. When the system frequency exceeds the preset range, a frequency regulation action is triggered to pull the frequency back to this range. If the frequency regulation action cannot pull the frequency back, a load regulation instruction is sent to the hydropower with good regulation performance through the logic operation control module of the regional integrated power supply power;

[0046] S3, setting the automatic start-stop strategy control module of the hydropower station. The hydropower station receives the load regulation instruction and executes it, and the difference is close to zero until the system frequency is pulled back to the preset range. If the maximum regulation amount of all hydropower stations with regulation capabilities in the area cannot meet the requirements of pulling the frequency back to the stable range, the hydropower station automatic start-stop strategy control module is used to start and stop the hydropower units to change the boundary conditions of the hydropower output power.

[0047] It is understandable that photovoltaic and wind power account for the largest proportion of renewable energy power in China's power system, and their volatility and intermittency are the most obvious. In order to reduce the power variation of the power system interconnection line, this paper takes photovoltaic and wind power as the output characteristics of renewable energy power and studies regional load balance.

[0048] The present invention changes the boundary conditions of the adjustable quantity by automatically starting and stopping in advance through the matching and complementation of hydropower, new energy, users, and tie lines. The specific implementation method is as follows:

[0049] This area integrates the power logic operation module, which is responsible for receiving active power data from photovoltaic, wind power, hydropower, thermal power, other power sources, interconnection lines, receiving ends, etc., and summarizing and calculating the input and output power of the power supply, setting the photovoltaic input power as P g(i) , wind power input power is P f(i) , the hydropower input power is P s(i) , other power input power is P q(i) , then the total input power in this area is P r =∑[P g(i) +P f(i) +P s(i) +P q(i) ]; Set the tie line power to P l(i) (For integrated power modules, the input is positive and the output is negative), the receiving end power is P y(i) , then the total output power is P c =∑[P l(i) +P y(i) ], the power grid capacity of a certain region is 2300MW, of which hydropower is 1600MW, photovoltaic power is 300MW, and wind farm is 400MW. The power generation trend is as follows Figure 2 shown.

[0050] Specifically, the intelligent start-stop logic of the regional hydropower unit of the present invention is as follows: Figure 3 As shown, the following steps are included:

[0051] S1000) Setting a regional photovoltaic power station output power calculation module to collect and calculate the sum of the total grid-connected output powers of each photovoltaic power station.

[0052] The power of the photovoltaic power station is collected through the power collection modules of all photovoltaic power stations in the area, and the collected power is sent to the integrated power logic operation module in the area. Assuming that there are n photovoltaic power stations in this area, the total photovoltaic input power is The daily photovoltaic curve is parabolic, and no electricity is generated at night. Generally, 11:00 to 14:00 is the peak period of power generation. The power generation distribution of a photovoltaic power station with an installed capacity of 300MW is shown in Table 1:

[0053] Table 1

[0054]

[0055] S2000) A regional wind power plant output power calculation module is set to collect and calculate the sum of the total grid-connected output power of each wind power plant.

[0056] The power of the photovoltaic power station is collected through the power collection modules of all wind power stations in the area, and the collected power is sent to the integrated power logic operation module in the area. Assuming that there are n wind power stations in this area, the total photovoltaic input power is The daily wind power curve is completely irregular and has no regularity. The wind power generation of the next day can only be evaluated through wind power forecast. It has strong volatility and high requirements for system matching. The daily power generation distribution of a 300MW wind farm is shown in Table 2:

[0057] Table 2

[0058]

[0059] S3000) A regional hydropower station adjustable power calculation module with regulation capability is set to collect and calculate the sum of the adjustable power ranges of each hydropower station to form a total regional system adjustable range.

[0060] The regional integrated power supply logic operation module accepts the safety boundary conditions from all hydropower stations in the region, and screens them according to the safety boundary conditions, classifying the hydropower stations with regulation capabilities into one category and the hydropower stations without regulation capabilities into other power categories.

[0061] S3100) collects the power of the hydropower stations through the power collection modules of all hydropower stations with regulation capabilities in the area, and sends the collected power to the integrated power logic operation module in the area. Assuming that there are n hydropower stations with regulation capabilities in this area, the total hydropower input power is Hydropower has flexible regulation. In order to match the instability and intermittency of new energy, the distribution of hydropower generation is generally automatically matched to the instability of the sending and receiving ends of the power system. When the proportion of new energy power was small in the early stage, hydropower mainly matched the changes in the receiving end. Its daily power generation curve generally presents a double hump. With the increase in the proportion of new energy power, especially the increase in photovoltaic power, the midday trough of hydropower will last longer and the transmission load will be smaller. It undertakes the important peak-shaving task of the power system. The daily power generation distribution of a 1600MW hydropower plant is shown in Table 3:

[0062] Table 3

[0063]

[0064] S3200) There are n hydropower stations with regulation capabilities in the area. The upward adjustable capacity of each hydropower station is "the maximum technical output limit of the whole plant - the current active power" = P上 , then the total upward adjustable capacity of n hydropower stations is The downward adjustable capacity of each hydropower station is "current active power - minimum technical output limit" = P 下 , then the total downward adjustable capacity of n hydropower stations is

[0065] S4000) sets a module for calculating the output power of other non-adjustable power supplies in the region, collects and calculates the sum of the output power of all non-adjustable power supplies, and this part bears the base load in the region.

[0066] The power collection module of the power supply without regulation capability in the area collects the output power of each power supply without regulation capability, and sends the collected power to the integrated power supply logic operation module in the area. Assuming that there are n power supplies without regulation capability in this area, the total input power is This part bears the base load in the power system and does not participate in system regulation.

[0067] S5000) A regional interconnection line transmission power calculation module is set. For this region, the outgoing power is positive and the incoming power is negative. The sum of the total output power of the interconnection lines is collected and calculated.

[0068] The transmission power of each tie line is collected through the tie line power collection module in the area. The input is positive and the output is negative. The collected power is sent to the integrated power logic operation module in the area. Assuming that there are n tie lines in this area, the total output power is

[0069] S6000) Set up a regional receiving end power calculation module to collect and calculate the sum of all receiving end powers.

[0070] The receiving end power is collected through the receiving end power collection module in this area, and the collected power is sent to the integrated power supply logic operation module in this area. Assuming that there are n receiving ends in this area, the total sent power is.

[0071] S7000) Set up a logic operation control module for the regional "photovoltaic + wind power + hydropower + other power sources - interconnection line power - receiving end power - transmission loss" integrated power source power. This module classifies photovoltaic, wind power and other non-adjustable power sources with variable output power at any time as a type of power source, classifies other non-adjustable power sources with stable output power as a type of power source, and classifies thermal power and other power sources with stable and adjustable output power but poor adjustable performance as a type of power source. When "photovoltaic + wind power + hydropower + other power sources - interconnection line power - receiving end power - transmission loss" is not equal to 0, it shows that the power system frequency changes, and a regional frequency analysis control module is set. If the frequency change is within the range of 50±0.06Hz, it meets the system stability requirements. When the system frequency exceeds this range, a frequency regulation action is triggered to pull the frequency back to the secondary range. If the frequency regulation action still cannot pull the frequency back, the integrated power source logic operation control module will give priority to sending load regulation instructions to hydropower with good regulation performance, that is, the secondary frequency regulation of the system.

[0072] S8000) sets an automatic start-stop strategy control module for the hydropower station. The hydropower station receives the above power adjustment command and executes it, and makes "photovoltaic + wind power + hydropower + other power sources - interconnection line power - receiving end power - transmission loss" close to 0 until the system frequency is pulled back to the range of 50±0.06Hz. If the maximum adjustment amount of all hydropower stations with adjustment capabilities in the area still cannot meet the requirements of pulling the frequency back to the stable range, the automatic start-stop strategy control module of the hydropower station can be used to start and stop the hydropower units to change the boundary conditions of the hydropower output power. In this case, early start-up and shutdown are the core of the present invention.

[0073] S8100) For the specific implementation method, the regional type is reduced to the decomposition of the water, wind and light station model, and the water, wind and light stations are prioritized for balance. The following relationship exists. Within a period of Δt, the change in the set value issued by the active power dispatch of this station is ΔPd, the change in the sum of wind power and photovoltaic power of this station is ΔPx, and the change in the active power of hydropower of this station is ΔPs. Then its balance satisfies ΔPd=|ΔPs-ΔPx|. Whether the matching balance process here may cause low-frequency oscillation of the power system depends on whether ΔPs exceeds the adjustable boundary of the hydropower station. The adjustable boundary of the hydropower station can be changed by changing the number of running units, thereby avoiding the possibility of causing low-frequency oscillation of the system frequency. As for the triggering conditions for the automatic early start of the hydropower station, they are divided into the following types:

[0074] S8110) Trigger condition: daily active power plan curve + frequency modulation winning bid curve. For hydropower station switch stations that are connected to both photovoltaic and wind power, hydropower will give priority to balancing photovoltaic and wind power at the same station. To ensure early startup, the daily plan curve + frequency modulation winning bid curve sent to the hydropower station by the dispatcher can be used to start the power in advance for a certain period of time, and shut down after a certain period of time, thereby increasing the adjustable upper and lower limits of the system in advance;

[0075] S8120) Assume that at time t, the daily active power plan curve + the frequency regulation winning curve of the hydropower station = Pt, the maximum output of the hydropower station unit is Ph, the upper edge value of the vibration zone of the hydropower station unit is Ps, and the number of operating units is n. When Pt>nPh, the unit is started at t-15 minutes to meet the daily active power plan curve + the frequency regulation winning curve in advance. When Pt<nPs+20MW, the unit is shut down to expand the lower limit of system load reduction in advance.

[0076] S8210) Trigger condition: Free adjustable capacity. Free adjustable capacity is the capacity that can be adjusted upward and downward based on the actual value of the whole plant's active power. When the upward free adjustable capacity is less than the set value, it triggers the start-up, and when the downward free adjustable capacity is less than the set value, it triggers the shutdown, which can realize early start and shutdown to meet the upper and lower limit boundaries of the adjustable system.

[0077] S8310) Selection method for automatic start and stop of hydropower units. First, based on the comparison of the regulation performance of the hydropower station AGC, such as regulation accuracy, response time, and regulation rate, the comprehensive regulation performance of the hydropower station is set to k. The smaller the k value, the better the regulation performance of the hydropower station. The regulation performance of n hydropower stations in the area is: k1, k2...k n-1 , k n , the regional power logic operation module selects min(k1, k2...k n-1 , k n ) = k m , then the module sends a start or stop command to the m hydropower station, and the m hydropower station performs automatic start or stop operations.

[0078] S8320)m Hydropower station start-up and shutdown sequence selection method, assuming the number of hydropower units is n, set the unit priority 1, 2, 3...n, 1 is the highest priority, n is the lowest priority, the priority of the plant-level AGC operation unit is higher than the priority of the standby unit. When receiving the start-up command, the unit with the highest priority among the standby units will be started first. When receiving the shutdown command, the unit with the highest priority among the running units will be shut down first. At this time, the priority of the shutting unit becomes the lowest, that is, n, and the priority of other units is reduced by 1 at a time. This priority selection of unit start-up and shutdown can automatically realize the rotation start-up and shutdown of the hydropower station units.

[0079] S8330) Hydropower unit optimization module startup mode, this module accurately selects the hydropower units suitable for the current regional operating conditions according to the power demand and hydropower resource conditions in the region, and gives priority to small-scale high-efficiency and optimal performance hydropower units for operation during low-load periods to avoid the inefficient operation of large units; and during peak high-load demand periods, large-capacity hydropower units are started to meet power demand, thereby avoiding the oscillation risk caused by the rapid fluctuation of new energy sources such as photovoltaic and wind power.

[0080] Specifically, Figure 4 This is a schematic diagram of the load flow of the regional power supply computing module of the present invention. Figure 5 The preferred logic diagram of the hydroelectric unit of the present invention; the specific steps of S7000)-S8000) of the present invention are as follows:

[0081] The power logic operation module is integrated in this area to perform node calculation, that is, P r -P c =ΔP, when ΔP is positive, the system shows a frequency increase. When the rising frequency reaches 50+0.06Hz, the primary frequency modulation is triggered to adjust downward. When the primary frequency modulation action still cannot pull the frequency back to less than 50+0.06Hz, the secondary frequency modulation is triggered. The integrated power supply logic operation control module gives priority to sending load reduction instructions to hydropower with good regulation performance until the frequency is reduced to less than 50+0.06Hz again; when ΔP is negative, the system frequency shows a decrease. When the decreasing frequency reaches 50-0.06Hz, the primary frequency modulation is triggered to adjust upward. When the primary frequency modulation action still cannot pull the frequency back to more than 50-0.06Hz, the secondary frequency modulation is triggered. The integrated power supply logic operation control module gives priority to sending load increase instructions to hydropower with good regulation performance until the frequency is increased to more than 50-0.06Hz again.

[0082] When the secondary frequency regulation action is triggered, the integrated power supply logic operation module will send the regulation instructions to the hydropower stations with better regulation performance based on the collected power supply information with regulation capability, and execute load adjustment. When the upward or downward regulation capacity of this area is insufficient, the system frequency oscillation may be caused by changes in the transmission power of wind power and photovoltaic power.

[0083] During a period of Δt, the sum of the changes in photovoltaic and wind power is ΔPx. The integrated power supply logic operation module needs to send the active regulation value change ΔPd to the hydropower station. However, due to the safety boundary conditions of the hydropower station, the hydropower regulation change range is [Ps(min), Ps(max)]. When ΔPd=|ΔPs-ΔPx|regulation cannot be met, the system frequency will increase or decrease. During a period of Δt, if the output power of photovoltaic and wind power fluctuates, the system adjustable capacity will sometimes be satisfied and sometimes not, and the system frequency will also fluctuate, that is, the system frequency oscillates.

[0084] In order to solve this problem, the present invention considers changing the range of hydropower regulation variation by automatically starting and stopping the machine, that is, by changing the hydropower safety boundary conditions, to compensate for the problem of insufficient hydropower matching regulation.

[0085] When the power system in the region lacks downward regulation capacity, it will be manifested as obstruction in reducing power generation, resulting in an increase in system frequency. If the output power of renewable energy fluctuates, it may cause system frequency oscillation. The safety boundary conditions of the adjustable hydropower station can be changed by shutting down in advance to free up more room for downward regulation.

[0086] For example, the minimum technical output limit of a hydropower station is n*P zs , n is the number of AGC units in operation in the hydropower station, P zs The upper edge value of the vibration zone of the hydropower station unit, when the downward adjustment capacity is insufficient, after stopping one unit, the minimum technical output lower limit of the whole plant is n*P zs becomes (n-1)*P zs , and each hydropower station will implement it in turn, releasing more downward regulation capacity in advance to achieve complementary matching between hydropower and new energy electricity.

[0087] When the power system in the region has insufficient upward adjustment capacity, it will be hindered from increasing the power generation and the system frequency will drop. If the output power of new energy fluctuates, it may cause the system frequency to oscillate. The safety boundary conditions of the adjustable hydropower station can be changed by starting the power in advance to increase the upward adjustment space. For example, the maximum technical output limit of a hydropower station is n*P h , n is the number of AGC units in operation in the hydropower station, P h The maximum output of the hydropower station unit, when the upward adjustment capacity is insufficient, after starting a spare unit, the maximum output limit of the whole plant is n*P h becomes (n+1)*P h , and each hydropower station will implement it in turn, releasing more upward regulation capacity in advance to achieve complementary matching between hydropower and new energy electricity.

[0088] The main strategies for realizing the early start-up and shutdown mode according to the "plan curve + frequency modulation winning bid curve" are as follows:

[0089] The daily active power plan curve issued by the dispatcher is a discrete type with one point every 5 minutes. The daily plan curve issued by the dispatcher is interpolated and split to form a high-density dispersed value with one point every 10 seconds to draw the daily active power plan curve;

[0090] The step-type curve of the frequency modulation bid is based on the hourly period. It is not split here, but directly superimposed with the split high-density daily plan curve to draw the superimposed active power plan curve;

[0091] The active power plan curve value P after the hydropower is superimposed on the daily plan and the frequency regulation bid t, and the maximum output of the hydropower station unit under the current head, the number of operating units is obtained through the following hydropower station automatic start and stop logic operation. When the number of operating units does not match the active power plan curve, the start and stop operations are automatically performed to meet the secondary frequency regulation requirements of the system.

[0092] For the automatic startup setting, the main consideration parameter is the maximum technical output upper limit. Combined with the actual unit start-up order from the issuance of the start-up order to the grid connection time, the advance startup method is adopted. For example, according to the planned curve, the start-up is 15 minutes in advance, and the unit start-up order is issued to the grid connection time of 8 minutes, that is, the active power plan curve value P within 15 minutes after the automatic start-up and shutdown logic operation device scans t15 , when there are n units in operation in the whole plant, the maximum technical output limit is n*P h , when the scan detects the active power plan curve value P within 15 minutes t15 >n*P h When the power is on, a standby unit will be automatically started. According to the time from startup to grid connection, the maximum technical output limit will be increased to (n+1)*P 7 minutes in advance. h , meet the requirements of dispatching active power set value, frequency regulation winning curve and daily active power planning curve in advance.

[0093] After automatic startup, the unit's single-machine AGC is automatically put into operation through the automatic start-stop device. When the active power of the unit is matched and adjusted with the active power of other units, the unit's single-machine AVC is automatically put into operation through the automatic startup device to balance the reactive power between units. By adjusting the active and reactive power separately, frequency and voltage fluctuations caused by simultaneous adjustment can be avoided.

[0094] For the automatic shutdown setting, the minimum shutdown mode principle is adopted to provide the system with the maximum spinning reserve capacity under the current mode. The main consideration parameter is the minimum technical output lower limit. According to the AGC control strategy of the Southern Power Grid area, the calculation method for the minimum technical output lower limit of the hydropower station is: the minimum technical output lower limit of a single machine is the upper edge value of the unit vibration zone P z上 There are n units in the plant that have AGC, and the total active load of the units without AGC is P 未 , then the minimum technical output lower limit of the whole plant is n*P z上 +P 未 , this shutdown strategy adopts 20MW down-running in advance. When the dispatcher sends the active setting value P d ∈[n*P z上 +P 未 ,n*P z上 +P 未+20MW], the automatic start-stop logic operation device automatically selects a unit to cross the vibration zone, reduces the active power to within the allowable shutdown range, automatically exits the single-unit AGC of the unit, automatically adjusts the reactive power to within the allowable range, and automatically exits the single-unit AVC of the unit.

[0095] The automatic start-stop device detects that the shutdown conditions of the unit are met, automatically issues a shutdown command, and the monitoring system automatically executes the shutdown command. If the shutdown process is normal, the automatic shutdown is completed. Then the minimum technical output lower limit of the hydropower station is also n*P before the shutdown. z上 +P 未 becomes (n+1)*P z上 +P 未 By timely shutting down, the safety boundary conditions of the hydropower station can be changed to meet the dispatching active power set value, frequency regulation winning curve, daily active power plan curve, and new energy complementary matching needs.

[0096] Realize the automatic start and stop mode calculated according to the "free adjustable capacity". The free adjustable capacity refers to the capacity that can be adjusted upward and downward based on the actual value.

[0097] Assume that the current active power value is P 实 , upward freely adjustable capacity n*P h -P 实 , set the upward freely adjustable capacity to 40MW, when n*P h -P 实 When the power is less than or equal to 40MW, a standby unit is started through the automatic start-stop device. After the unit is connected to the grid, the standby AGC of the unit is automatically put into operation. After the active power is balanced and distributed, the AVC of the unit is automatically put into operation. The automatic start-up is completed. At this time, the hydropower station can freely adjust the capacity upward by n*P h -P 实 becomes (n+1)*P h -P 实 , meeting the needs of dispatching active power set value, frequency regulation bidding curve, daily active power planning curve, and new energy complementary matching.

[0098] Freely adjustable capacity downward P 实 -n*P z上 , set the upward freely adjustable capacity to 30MW, when P 实 -n*P z上 When the power is less than or equal to 30MW, a unit is selected to stop by the automatic shutdown device when it passes through the vibration zone. After the active power of the unit is reduced to the allowable shutdown range, it automatically exits the AGC of the unit. After the reactive power is automatically adjusted to the allowable shutdown range, it automatically exits the AVC of the unit and executes the automatic shutdown. At this time, the hydropower station can freely adjust the capacity downward by P 实 -n*P z上 Change to P实 -(n-1)*P z上 , meeting the needs of dispatching active power set value, frequency regulation bidding curve, daily active power planning curve, and new energy complementary matching.

[0099] After the regional centralized power supply calculation module calculates and satisfies the hydropower station startup conditions, the unit optimization startup module is triggered. Assume that there are N hydropower units and the power generation power of the i-th hydropower unit is P i , whether the i-th hydropower unit is selected is variable Y i , the maintenance cost and daily operation and maintenance cost of the i-th unit is J(Y), and the optimal function of the hydropower unit is To ensure that hydropower units can generate electricity at the highest efficiency under different load conditions, thereby maximizing the utilization efficiency of hydropower resources.

[0100] Assume that the total hydropower active demand in the selected area is P d , then the optimal power demand constraint condition for hydropower units is Selected unit capacity P i Constraints P i,min ·Y i ≤P i ≤P i,man ·Y i , where P i,man and P i,min is the maximum active power and minimum active power of the i-th hydropower unit, thereby ensuring the optimal operation of the regional hydropower units.

[0101] Whether it is to achieve automatic start and shutdown according to the frequency regulation winning curve + daily plan curve to avoid system frequency oscillation, or to achieve automatic start and shutdown according to the freely adjustable capacity to avoid system frequency oscillation, the most fundamental principle is to sense the adjustable boundary of the hydropower station and use technical means to change the boundary conditions of the hydropower station in advance through automatic start and shutdown, so as to achieve the purpose of changing the adjustable boundary of the system.

[0102] S9000) Hydropower stations with regulation capabilities are put into plant-level AGC control. The hydropower station dispatches active power set values, AGC unit guide vane opening, minimum technical output lower limit, and maximum technical output upper limit through situation awareness detection, and determines the start or shutdown in advance, thereby providing more adjustment space for the system regulation demand and meeting the system regulation demand.

[0103] The beneficial effects of the present invention are as follows:

[0104] 1. The control method of the present invention for avoiding system oscillation caused by fluctuations in renewable energy power through intelligent start and stop of hydropower units is based on full consideration of the basic structure of the regional power grid, combined with the rapid development of renewable energy power, and based on the complementary matching between unstable power sources and adjustable power sources. A control method for automatic start and stop of hydropower stations is added to break the original power system safety boundary conditions and change the original power system boundary parameters, thereby enabling the power system to have stronger adaptive capabilities.

[0105] 2. The control method of the present invention for avoiding system oscillation caused by fluctuations in renewable energy power through intelligent start and stop of hydropower units is mainly to solve the stability problem of the power system when the adjustment range of secondary frequency regulation is limited except for primary frequency regulation. It fully considers the national power market reform, superimposes the winning bid curve of the frequency regulation market on the daily plan curve, and realizes automatic start and stop by sensing the freely adjustable capacity. This technology can meet the system requirements more closely, and can increase the system power load adjustment bandwidth in advance through automatic start and stop, so as to avoid the system oscillation problem caused by fluctuations in renewable energy power.

[0106] 3. The present invention adopts a control method to avoid system oscillation caused by fluctuations in renewable energy power through the intelligent start and stop of hydropower units. By starting the units in a set order and optimizing the two starting modes, combined with the power demand and load characteristics in the region, the hydropower units to be started are reasonably selected to achieve optimal power allocation in the region. At the same time, it can effectively solve the risk of system oscillation caused by unit abnormalities during peak power consumption periods or important power supply guarantee periods, ensure continuous and stable power supply in the region, provide solid power support for the regional power grid, and provide favorable guarantees for power supply in different regions and areas.

[0107] 4. The control method of the present invention avoids system oscillation caused by fluctuations in renewable energy power through intelligent start and stop of hydropower units. At present, the start and stop mode of large-scale hydropower in China is basically manual command, and the start and stop process is automatically executed. However, there may be lags or advances in the manual command link. Whether it is a lag or advance, it will bring uncertainties to the stability of the power system. This technology changes the free adjustable capacity of the regional power system by starting the unit at a controllable time in advance and shutting down on time. It is an improvement in the degree of intelligence and an innovation that liberates labor. After the technology is realized, the personnel are completely liberated from the whole process of starting-adjusting-shutdown of the hydropower station unit, and the automatic start and shutdown realized by the program are more timely, and the adjustment and matching process is more stable and safe.

[0108] According to the control method of the embodiment of the present invention, the intelligent start and stop of the hydropower unit is used to avoid the system load oscillation caused by the fluctuation of the new energy power, and the hydropower rotating reserve capacity is called in advance, and the timely shutdown provides a sufficient adjustable lower limit to improve the adjustable capacity of the hydropower, and provide the greatest support for the system frequency stability. The adjustable hydropower station has the intelligent start and stop function of the unit, and can realize fully automatic start and shutdown control according to the system load. When the power generation output of the grid-connected units of the hydropower station has reached the maximum output upper limit under the current water head or is close to the maximum output upper limit, the standby units can be automatically started to provide more rotating reserve capacity; when the output of the grid-connected units of the hydropower station has reached or is close to the minimum technical output lower limit, it can automatically pass through the vibration zone to perform shutdown operations, providing more load reduction space, thereby providing reliable protection for the stability of the power system and avoiding system oscillations caused by the fluctuation of new energy power.

[0109] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0110] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

Claims

1. A control method for avoiding system load oscillation caused by new energy power fluctuations by using intelligent start and stop of hydropower units, characterized in that: include: The regional photovoltaic power station output power calculation module is used to calculate the total grid-connected output power of each photovoltaic power station, the regional wind power plant output power calculation module is used to calculate the total grid-connected output power of each wind power plant, the regional hydropower station adjustable power calculation module with regulation capability is used to calculate the adjustable power of each hydropower station, the regional other non-adjustable power supply output power calculation module is used to calculate the output power of all non-adjustable power supplies, the regional interconnection line transmission power calculation module is used to calculate the total output power of the interconnection line, and the regional receiving end power calculation module is used to calculate all receiving end powers; The logic operation control module of regional integrated power source power is used to calculate the difference between the sum of the total grid-connected output power of each photovoltaic power station, the total grid-connected output power of each wind power plant and the adjustable power of each hydropower station and the output power of the non-adjustable power source, the total output power of the tie line, the receiving end power and the transmission loss power. When it is judged that the difference is not equal to zero, it is shown that the power system frequency changes. If the frequency change is within the preset range, the system stability requirement is met. When the system frequency exceeds the preset range, a frequency regulation action is triggered to pull the frequency back to this range. If the frequency regulation action cannot pull the frequency back, a load regulation instruction is sent to the hydropower with good regulation performance through the logic operation control module of regional integrated power source power. An automatic start-stop strategy control module for the hydropower station is set up. The hydropower station receives and executes the load adjustment command, and the difference is close to zero until the system frequency is pulled back into the preset range. If the maximum adjustment amount of all hydropower stations with adjustment capabilities in the area cannot be satisfied to pull the frequency back into the stable range, the automatic start-stop strategy control module of the hydropower station is used to start and stop the hydropower units to change the boundary conditions of the hydropower output power.

2. The method according to claim 1, characterized in that The logic operation control module of the regional integrated power source power is used to receive active power data from photovoltaic, wind power, hydropower, thermal power, other power sources, tie lines, and receiving ends, and the input and output power are respectively summarized and calculated, and the photovoltaic input power is set as P g(i) , wind power input power is P f(i) , the hydropower input power is P s(i) , other power input power is P q(i) , the total input power in the area is P r =∑[P g(i) +P f(i) +P s(i) +P q(i) ]; Set the tie line power to P l(i) , the receiving end power is P y(i) , the total output power is P c =∑[P l(i) +P y(i) ].

3. The method according to claim 2, characterized in that The power of the photovoltaic power station is collected through the power collection modules of all photovoltaic power stations in the region, and the collected power is sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n photovoltaic power stations in this area, the total photovoltaic input power is:

4. The method according to claim 2, characterized in that: The power of the photovoltaic power station is collected through the power collection modules of all wind power stations in the region, and the collected photovoltaic power station power is sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n wind power stations in this area, the total photovoltaic input power is:

5. The method according to claim 2, characterized in that: The logic operation control module of the regional integrated power supply receives the safety boundary conditions from all the hydropower stations in the region, and screens them according to the safety boundary conditions. The power supplies that are not adjustable and whose output power can be changed at any time are classified as the first type of power supply, the other non-adjustable power supplies and the power supplies with stable output power are classified as the second type of power supply, and the power supplies with stable and adjustable output power but poor adjustable performance are classified as the third type of power supply.

6. The method according to claim 2, characterized in that The output power of each power supply without regulation capability is collected through the power collection module of the power supply without regulation capability in the area, and the collected output power of each power supply without regulation capability is sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n power supplies without regulation capability in this area, the total input power is:

7. The method according to claim 2, characterized in that The transmission power of each tie line is collected through the tie line power collection module in the area, where the input is positive and the output is negative, and the collected transmission power of each tie line is sent to the logic operation control module of the regional integrated power supply power. Assuming that there are n tie lines in this area, the total output power is:

8. The method according to claim 2, characterized in that: The receiving end power is collected by the regional receiving end power collection module and sent to the regional integrated power supply power logic operation control module. Assuming that there are n receiving ends in this area, the total output power is:

9. The method according to claim 2, characterized in that: The node calculation is performed through the logic operation control module of the regional integrated power supply, that is, P r -P c =ΔP, when ΔP is positive, the system shows a frequency increase. When the rising frequency reaches 50+0.06Hz, the primary frequency modulation is triggered to adjust downward. When the primary frequency modulation action cannot pull the frequency back to less than 50+0.06Hz, the secondary frequency modulation is triggered. The logic operation control module of the regional integrated power supply power gives priority to sending load reduction instructions to the hydropower with good regulation performance until the frequency is reduced to less than 50+0.06Hz again; when ΔP is negative, the system frequency shows a decrease. When the decreasing frequency reaches 50-0.06Hz, the primary frequency modulation is triggered to adjust upward. When the primary frequency modulation action cannot pull the frequency back to more than 50-0.06Hz, the secondary frequency modulation is triggered. The logic operation control module of the regional integrated power supply power gives priority to sending load increase instructions to the hydropower with good regulation performance until the frequency is increased to more than 50-0.06Hz again.

10. The method according to claim 1, characterized in that The method also includes putting a hydropower station with regulation capability into plant-level AGC control. The hydropower station dispatches active power set values, AGC unit guide vane openings, minimum technical output lower limit, and maximum technical output upper limit through situation awareness detection, and determines startup or shutdown in advance to provide regulation space for system regulation demand and meet system regulation demand.

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