Water-light complementary new energy consumption maximization regulation and control method based on autotransformer

Abstract

The invention discloses a water-light complementary new energy consumption maximization regulation and control method based on an autotransformer, and the method comprises the steps: determining the water-light consumption priorities of a medium-voltage side and a low-voltage side of the autotransformer based on the non-overload information of a common winding of the autotransformer; according to the water level information of the hydropower station reservoir, determining the medium-voltage side water-light absorption priority of the autotransformer; and realizing photovoltaic absorption maximization based on regulation and control of water-light absorption priority, and calculating the transmission power of the high-voltage side of the autotransformer. The low-voltage side of the autotransformer of the hydropower station is suitable for being connected with a photovoltaic device, power is transmitted to the high-voltage side through the photovoltaic device on the low-voltage side, the limitation of overload of the public winding of the autotransformer can be avoided, the load capacity of the transformer is improved, and the capacity of the transformer is fully utilized.

Description

Technical Field

[0001] The present invention relates to the technical field of clean energy multi-energy complementarity, and in particular to a method for maximizing the control of water-photovoltaic complementary new energy consumption based on an autotransformer. Background Art

[0002] New energy sources, mainly wind power and photovoltaic power, have become an important way to ensure energy security and respond to global warming. However, wind power and photovoltaic power are random, volatile and unadjustable, which restricts their large-scale grid connection and absorption. Using the natural complementarity of resources and the flexibility of hydropower to implement multi-energy complementary operation is an effective way to promote the absorption of new energy. Hydropower and photovoltaic complementarity is to use the adjustment and compensation capabilities of hydropower stations with adjustment capabilities to give priority to compensation for photovoltaic power stations that are slightly closer, and use the excess adjustment capabilities of hydropower stations to meet the power load demand of the power grid, improve the absorption of photovoltaic power stations with large fluctuations, and ultimately maximize the benefits of power generation from hydropower stations and photovoltaic power stations.

[0003] At present, some hydropower stations are connected to photovoltaic power by adding autotransformers and expanding switch stations, making full use of the access conditions and regulation capabilities of existing hydropower stations to carry out water-photovoltaic complementarity, and drive the large-scale and integrated development of surrounding new energy. There is a direct electrical connection between the high-voltage and medium-voltage windings of the autotransformer, and there is a special problem of public winding overload, that is, under a certain operating mode of the transformer, the loads on the high-voltage, medium-voltage, and low-voltage sides do not exceed the rated capacity, but the apparent power of the public winding exceeds its rated capacity, so that the transformer cannot operate at full load, affecting its load capacity. The calculation instructions are as follows.

[0004] The formula for calculating the real-time apparent power of the common winding of the autotransformer is:

[0005]

[0006] The formula for calculating the rated apparent power of the common winding of the autotransformer is:

[0007] S oN =K b S N

[0008] Where: K b =1-1 / K 12 , K 12 S is the voltage ratio between the high and medium voltage sides of the autotransformer. N is the rated capacity of the transformer. P1, Q1, P3, Q3 are the active and reactive power of the high-voltage side and low-voltage side of the autotransformer respectively, and it is stipulated that the direction of the power input transformer of the high-voltage side and the low-voltage side is positive, and the direction of the power output transformer of the medium-voltage side is positive.

[0009] According to the above formula, combined with the power direction of the high voltage side, medium voltage side and low voltage side of the autotransformer, the following is analyzed:

[0010] When the autotransformer is operating in a mode where the medium voltage side simultaneously transmits active and lagging reactive power to the high voltage side and the low voltage side, the common winding will be overloaded, so that the high voltage side and the medium voltage side of the transformer cannot operate at full load.

[0011] When the autotransformer operates in a mode where the medium-voltage side and the low-voltage side simultaneously transmit active and lagging reactive power to the high-voltage side, the common winding will not be overloaded even if the high-voltage side and the medium-voltage side of the transformer operate at full load. Summary of the invention

[0012] The present invention aims to solve one of the technical problems in the related art at least to a certain extent.

[0013] To this end, the present invention proposes a method for maximizing the consumption of new energy sources of hydropower and photovoltaic power complementarity based on an autotransformer. Taking into account the time characteristics of photovoltaic grid-connected capacity, under the premise of ensuring that the autotransformer is not overloaded, hydropower is not abandoned, and photovoltaic consumption is maximized, this control method provides a new idea for the complementary scheduling of hydropower and photovoltaic power bundled and sent through the autotransformer, and provides a new method for improving the utilization rate of various clean energy sources.

[0014] Another object of the present invention is to propose a water-photovoltaic complementary new energy consumption maximization control system based on an autotransformer.

[0015] To achieve the above-mentioned purpose, the present invention proposes a method for maximizing the consumption of water-photovoltaic complementary new energy based on an autotransformer, comprising:

[0016] Based on the information that the common winding of the autotransformer is not overloaded, the priority of water and light consumption on the medium-voltage side and the low-voltage side of the autotransformer is determined;

[0017] Determine the priority of water-solar consumption on the medium-voltage side of the autotransformer based on the water level information of the hydropower station reservoir;

[0018] Based on the regulation and control that prioritizes water and light consumption, the photovoltaic consumption is maximized, and the transmission power on the high-voltage side of the autotransformer is calculated.

[0019] The method for maximizing the consumption of new energy sources of water-photovoltaic complementary energy based on autotransformer in the embodiment of the present invention may also have the following additional technical features:

[0020] In one embodiment of the present invention, the direction of the power input bus of the preset unit and line is positive, and the active power calculation formula on each side of the autotransformer is as follows:

[0021] P1=P2+P3 (1)

[0022] P2=P 2光 +P 2水 -P 2线 (2)

[0023] P3=P 3光 (3)

[0024] The autotransformer load constraints are as follows:

[0025] S o ≤S oN (4)

[0026] P1≤P 1N (5)

[0027] Among them, P1 is the real-time active power on the high-voltage side of the autotransformer, P2 is the real-time active power on the medium-voltage side of the autotransformer, P3 is the real-time active power on the low-voltage side of the autotransformer, and P 2水 is the real-time active power of hydropower on the medium voltage side of the autotransformer, P 2线 is the real-time active power of the medium voltage side line of the autotransformer, P 2光 is the real-time active power of photovoltaic power station B, P 3光 is the real-time active power of photovoltaic power station A, S O is the real-time apparent power of the common winding of the autotransformer, S ON is the rated apparent power of the common winding of the autotransformer, P 1N It is the rated power of the high voltage side of the autotransformer.

[0028] In one embodiment of the present invention, the common winding of the autotransformer must satisfy formula (4) when not being overloaded during operation. According to the overload analysis of the common winding of the autotransformer, when the low-voltage side of the transformer transmits active power and lagging reactive power to the high-voltage side, the common winding will not be overloaded, and the photovoltaic absorption priority of the low-voltage side of the autotransformer is set to the highest.

[0029] In one embodiment of the present invention, determining the priority of water-solar power consumption on the medium-voltage side of the autotransformer includes:

[0030] When the reservoir water level is below the permitted value, photovoltaic power generation is prioritized. The photovoltaic power on the medium voltage side operates at the maximum power generation capacity, and the power on the high voltage side satisfies formula (5). To avoid over-rated power on the high voltage side, the hydropower on the medium voltage side is adjusted according to the actual operation of the autotransformer. The output is reduced by the adjustment of the hydropower on the medium voltage side, and the difference is dynamically balanced by the hydropower on the high voltage side, so as to maintain the total hydropower output of the whole station unchanged within the given dispatching range. When the reservoir water level is above the permitted value, hydropower generation is prioritized. To avoid over-rated power on the high voltage side, the photovoltaic power on the medium voltage side determines the output upper limit according to the actual operation of the autotransformer.

[0031] In one embodiment of the present invention, determining the priority of water-solar power consumption on the medium-voltage side of the autotransformer further includes:

[0032] (1)H≤H max

[0033] Among them, H is the real-time water level of the hydropower station reservoir, H max Permissible water levels in hydropower station reservoirs;

[0034] The photovoltaic power generation on the low-voltage side and medium-voltage side of the autotransformer is operated at the maximum capacity, and the upper limit of the hydropower output on the medium-voltage side of the autotransformer is:

[0035] P 2水 max =P 1N -P 3光 -P 2光 +P 2线 (6)

[0036] When the photovoltaic output suddenly changes and increases, such as causing the real-time output of hydropower on the medium-voltage side of the autotransformer P 2水 ≥P 2水 max , medium-pressure side hydropower output reduction △P=P 2水 -P 2水 max , ensuring that the high-voltage side of the autotransformer does not exceed the rated capacity, and at the same time the hydropower on the high-voltage side increases the load according to △P to maintain the total hydropower output of the entire station within the given dispatching range;

[0037] When the photovoltaic output suddenly changes and decreases, the real-time hydropower output on the medium-voltage side of the autotransformer does not need to be adjusted, and the total hydropower output of the entire station is maintained within the given dispatching range;

[0038] (2)H≥H max

[0039] The photovoltaic power generation on the low voltage side of the autotransformer and the hydropower generation on the medium voltage side are operated at their maximum capacity. The upper limit of the photovoltaic power generation on the medium voltage side of the autotransformer is:

[0040] P 2光 max =P 1N -P 3光 -P 2水 +P 2线 (7)

[0041] (3)H max Setting principles

[0042] Taking into account the duration of the maximum photovoltaic output at noon, the flow time of the upstream hydropower station, and the storage capacity of the reservoir, the reservoir allowable water level H is set. max limit.

[0043] In one embodiment of the present invention, calculating the transmission power on the high-voltage side of the autotransformer includes:

[0044]

[0045] To achieve the above-mentioned purpose, the present invention proposes, on the other hand, a water-photovoltaic complementary new energy consumption maximization control system based on an autotransformer, comprising:

[0046] The first priority determination module is used to determine the water-solar consumption priority of the medium-voltage side and the low-voltage side of the autotransformer based on the information that the common winding of the autotransformer is not overloaded;

[0047] The second priority determination module is used to determine the priority of water-solar consumption on the medium-voltage side of the autotransformer according to the water level information of the hydropower station reservoir;

[0048] The photovoltaic absorption module is used to maximize photovoltaic absorption based on the regulation of water-solar absorption priority, and calculate the transmission power on the high-voltage side of the autotransformer.

[0049] The autotransformer-based water-photovoltaic complementary new energy consumption maximization control method and system of the embodiments of the present invention utilize the redundant regulation capacity of the hydropower station to meet the power load demand of the power grid, improve the consumption of photovoltaic power stations with large fluctuations, and ultimately maximize the benefits of power generation of hydropower stations and photovoltaic power stations.

[0050] 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

[0051] 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:

[0052] Figure 1 This is a flow chart of a method for maximizing the control of water-photovoltaic complementary new energy consumption based on an autotransformer according to an embodiment of the present invention;

[0053] Figure 2 This is a typical application scenario diagram of a water-photovoltaic complementary operation mode based on an autotransformer according to an embodiment of the present invention;

[0054] Figure 3 It is a structural schematic diagram of a water-photovoltaic complementary new energy consumption maximization control system based on an autotransformer according to an embodiment of the present invention. DETAILED DESCRIPTION

[0055] 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.

[0056] 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.

[0057] The following describes a method and system for maximizing the consumption of new energy sources of water-photovoltaic complementary energy based on an autotransformer according to an embodiment of the present invention with reference to the accompanying drawings.

[0058] Figure 1 : is a flow chart of a method for maximizing the control of water-photovoltaic complementary new energy consumption based on an autotransformer according to an embodiment of the present invention. Figure 1 As shown, the method includes but is not limited to the following steps:

[0059] S1, based on the information that the common winding of the autotransformer is not overloaded, determine the priority of water and light consumption on the medium voltage side and low voltage side of the autotransformer;

[0060] S2, according to the water level information of the hydropower station reservoir, determine the priority of water and light consumption on the medium voltage side of the autotransformer;

[0061] S3, based on the regulation of water-solar absorption priority, maximizes photovoltaic absorption and calculates the transmission power result on the high-voltage side of the autotransformer.

[0062] The autotransformer of the present invention is used as the main channel for water-photovoltaic power transmission. Considering that the photovoltaic grid-connected capacity has time characteristics, the rated capacity of the autotransformer is generally smaller than the total water-photovoltaic transmission capacity. Under the premise of satisfying the autotransformer overload, hydropower not abandoning water, and maximizing photovoltaic absorption, a method for maximizing the absorption of water-photovoltaic complementary new energy is studied and invented. Typical application scenarios of water-photovoltaic complementary based on autotransformers are as follows: Figure 2 shown.

[0063] The control constraints of the present invention are shown in Table 1:

[0064] Table 1

[0065] symbol illustrate <![CDATA[P1]]> Real-time active power of high voltage side of autotransformer <![CDATA[P 1N ]]> Rated power of high voltage side of autotransformer <![CDATA[P2]]> Real-time active power of medium voltage side of autotransformer <![CDATA[P3]]> Real-time active power of low voltage side of autotransformer <![CDATA[S O ]]> Real-time apparent power of common winding of autotransformer <![CDATA[S ON ]]> Rated apparent power of common winding of autotransformer <![CDATA[P 2线 ]]> Real-time active power of medium voltage line of autotransformer <![CDATA[P 2水 ]]> Real-time active power of hydropower on the medium voltage side of autotransformer <![CDATA[P 3光 ]]> Real-time active power of photovoltaic power station A <![CDATA[P 2光 ]]> Real-time active power of photovoltaic power station B H Real-time water level of hydropower station reservoir <![CDATA[H max ]]> Permissible water level of hydropower station reservoir

[0066] Hydropower station autotransformers usually connect three voltage level systems for operation. The reactive power on the high-voltage and medium-voltage sides of the autotransformer is generally balanced on-site by the hydropower units and is not transmitted through the autotransformer. Therefore, the power factor of the autotransformer can be approximated to 1. Figure 1 As shown, it is stipulated that the direction of the power input bus of the unit and line is positive, and the active power calculation formula on each side of the autotransformer is as follows:

[0067] P1=P2+P3(1)

[0068] P2=P 2光 +P 2水 -P 2线 (2)

[0069] P3=P 3光 (3)

[0070] The constraints of auto-transformer load are as follows:

[0071] S o ≤S oN (4)

[0072] P1≤P 1N (5)

[0073] Based on this, the specific method of the present invention includes:

[0074] In one embodiment of the present invention, the priority of water and light consumption on the medium voltage side and the low voltage side of the autotransformer is determined according to whether the common winding of the transformer is overloaded.

[0075] Specifically, when the autotransformer is in operation, the common winding must satisfy formula (4) to avoid overloading. According to the technical analysis of autotransformer common winding overload, when the transformer low-voltage side transmits active and lagging reactive power to the high-voltage side, the common winding will not be overloaded. Therefore, setting the photovoltaic consumption priority on the low-voltage side of the autotransformer to the highest can avoid the limitation of common winding overload, improve the transformer load capacity, and make full use of its capacity.

[0076] In one embodiment of the present invention, the priority of absorbing water and light on the medium-voltage side of the autotransformer is determined according to the water level of the hydropower station reservoir.

[0077] Specifically, the risk of short-term abandonment of solar power in the combined operation of hydropower and solar power mainly occurs in the following two situations: the first is when the reservoir water level reaches the allowable upper limit and the reservoir loses its regulating capacity; the second is when hydropower needs to increase its power generation output due to system demand, reservoir cascade scheduling, etc.

[0078] Priority of water and solar power consumption on the medium-voltage side of the autotransformer: When the reservoir water level is below the allowable value, photovoltaic power generation is prioritized. The photovoltaic power on the medium-voltage side operates at the maximum power generation capacity. The power on the high-voltage side must satisfy formula (5). To avoid over-rated power on the high-voltage side, the hydropower on the medium-voltage side is adjusted according to the actual operation of the autotransformer. The difference in output reduced by the adjustment of the medium-voltage hydropower is dynamically balanced by the high-voltage hydropower, maintaining the total hydropower output of the entire station within the given dispatching range; when the reservoir water level is above the allowable value, hydropower generation is prioritized. To avoid over-rated power on the high-voltage side, the photovoltaic power on the medium-voltage side determines the output upper limit according to the actual operation of the autotransformer. The specific steps are as follows:

[0079] (1)H≤Hmax

[0080] The photovoltaic power generation on the low-voltage side and medium-voltage side of the autotransformer is operated at the maximum capacity, and the upper limit of the hydropower output on the medium-voltage side of the autotransformer is:

[0081] P 2水 max =P 1N -P 3光 -P 2光 +P 2线 (6)

[0082] When the photovoltaic output suddenly changes and increases, such as causing the real-time output of hydropower on the medium-voltage side of the autotransformer P 2水 ≥P 2水 max , medium-pressure side hydropower output reduction △P=P 2水 -P 2水 max , ensuring that the high-voltage side of the autotransformer does not exceed the rated capacity, and at the same time, the hydropower on the high-voltage side increases the load according to △P to maintain the total hydropower output of the entire station within the given dispatching range. The increase or decrease of hydropower output needs to take into account the actual boundary conditions such as the vibration zone of the unit, the dead zone of single-unit load regulation, and avoid frequent unit adjustments.

[0083] When the photovoltaic output suddenly changes and decreases, the real-time hydropower output on the medium-voltage side of the autotransformer does not need to be adjusted, and the total hydropower output of the entire station is maintained unchanged within the given dispatching range.

[0084] (2)H≥H max

[0085] The photovoltaic power generation on the low voltage side of the autotransformer and the hydropower generation on the medium voltage side are operated at their maximum capacity. The upper limit of the photovoltaic power generation on the medium voltage side of the autotransformer is:

[0086] P 2光 max =P 1N -P 3光 -P 2水 +P 2线 (7)

[0087] (3)H max Setting principles

[0088] Taking into account the duration of the maximum photovoltaic output at noon, the flow time of the upstream hydropower station, and the storage capacity of the reservoir, the reservoir allowable water level H is reasonably set. max Restrictions: During the flood season, a certain margin should be left from the flood limit water level of the reservoir.

[0089] By optimizing reservoir scheduling, making full use of the reservoir's storage capacity, and conducting research on water conditions and the maximum water level in front of the dam, we can achieve water-photovoltaic complementarity without wasting water or light, and maximize photovoltaic absorption.

[0090] In one embodiment of the present invention, after the above steps, priority regulation is performed to maximize photovoltaic consumption, and the transmission power calculation formula of the high-voltage side of the autotransformer is as follows:

[0091]

[0092] In summary, the autotransformer of the present invention connects the three voltage level systems for operation, and photovoltaic stations are connected to the medium voltage and low voltage sides. The autotransformer serves as the main channel for water-photovoltaic power transmission, and is generally representative of the water-photovoltaic complementary mode. Considering that the photovoltaic grid-connected capacity has time characteristics, under the premise of satisfying the autotransformer not being overloaded, hydropower not being abandoned, and photovoltaic consumption being maximized, this control method provides a new idea for the complementary dispatch of hydropower and photovoltaics bundled and sent through the autotransformer, and provides a new method for improving the utilization rate of various clean energy sources.

[0093] In the embodiment of the present invention, the method for maximizing the consumption of new energy sources of water-photovoltaic complementary system based on autotransformer is suitable for connecting photovoltaic power to the low-voltage side of the autotransformer of the hydropower station. The low-voltage side photovoltaic power is used to transmit power to the high-voltage side, which can avoid the limitation of overload of the common winding of the autotransformer, improve the load capacity of the transformer, and make full use of its capacity. The consumption priority of different energy sources in the water-photovoltaic complementary system should give priority to the consumption of photovoltaic power while ensuring that no water is abandoned. In the dry season of hydropower, the water inflow is small, and the daily output of hydropower is also small. The combined output of water and photovoltaic power does not exceed the capacity of the autotransformer, and the phenomenon of abandoning photovoltaic power will not occur. In the flood season, water situation forecasts and reservoir scheduling should be done well, and the allowable water level limit of the reservoir should be set reasonably, so that the consumption of photovoltaic power can be maximized without abandoning water on the day after complementation.

[0094] In order to implement the above embodiment, Figure 3 As shown, this embodiment also provides a water-photovoltaic complementary new energy consumption maximization control system 10 based on an autotransformer, including:

[0095] The first priority determination module 100 is used to determine the water-solar consumption priority of the medium-voltage side and the low-voltage side of the autotransformer based on the information that the common winding of the autotransformer is not overloaded;

[0096] The second priority determination module 200 is used to determine the priority of water-solar consumption on the medium-voltage side of the autotransformer according to the water level information of the hydropower station reservoir;

[0097] The photovoltaic absorption module 300 is used to maximize photovoltaic absorption based on the regulation of water-solar absorption priority and calculate the transmission power on the high-voltage side of the autotransformer.

[0098] In the autotransformer-based water-photovoltaic complementary new energy consumption maximization control system of the embodiment of the present invention, the low-voltage side of the autotransformer of the hydropower station is preferably connected to photovoltaics, and power is transmitted to the high-voltage side through the low-voltage photovoltaics, which can avoid the limitation of the autotransformer common winding overload, improve the load capacity of the transformer, and make full use of its capacity. The priority of absorbing different energy sources in the water-photovoltaic complementary system should give priority to the absorption of photovoltaics while ensuring that water is not abandoned. During the dry season of hydropower, the water inflow is small, and the daily output of hydropower is also small. The combined output of water and photovoltaics does not exceed the capacity of the autotransformer, and the phenomenon of abandonment of photovoltaics will not occur; during the flood season, water situation forecasts and reservoir scheduling should be done well, and the allowable water level limit of the reservoir should be set reasonably, so that the absorption of photovoltaics can be maximized without abandoning water on the day after complementation.

[0099] 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.

[0100] 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 method for maximizing the consumption of new energy from water and photovoltaic complementary power generation based on autotransformers, characterized in that: include: Based on the information that the common winding of the autotransformer is not overloaded, the priority of water and light consumption on the medium-voltage side and the low-voltage side of the autotransformer is determined; Determine the priority of water-solar consumption on the medium-voltage side of the autotransformer based on the water level information of the hydropower station reservoir; Based on the regulation and control that prioritizes water and light consumption, the photovoltaic consumption is maximized, and the transmission power on the high-voltage side of the autotransformer is calculated.

2. The method according to claim 1, characterized in that Assuming that the direction of the power input bus of the unit and line is positive, the active power calculation formula on each side of the autotransformer is as follows: P1=P2+P3 (1) P2=P 2光 +P 2水 -P 2线 (2) P3=P 3光 (3) The autotransformer load constraints are as follows: S o ≤S oN (4) P1≤P 1N (5) Among them, P1 is the real-time active power on the high-voltage side of the autotransformer, P2 is the real-time active power on the medium-voltage side of the autotransformer, P3 is the real-time active power on the low-voltage side of the autotransformer, and P 2水 is the real-time active power of hydropower on the medium voltage side of the autotransformer, P 2线 is the real-time active power of the medium voltage side line of the autotransformer, P 2光 is the real-time active power of photovoltaic power station B, P 3光 is the real-time active power of photovoltaic power station A, S O is the real-time apparent power of the common winding of the autotransformer, S ON is the rated apparent power of the common winding of the autotransformer, P 1N It is the rated power of the high voltage side of the autotransformer.

3. The method according to claim 2, characterized in that When the autotransformer is in operation, the common winding must satisfy formula (4) to avoid overloading. According to the overload analysis of the common winding of the autotransformer, when the low-voltage side of the transformer transmits active power and lagging reactive power to the high-voltage side, the common winding will not be overloaded, and the photovoltaic consumption priority of the low-voltage side of the autotransformer is set to the highest.

4. The method according to claim 2, characterized in that: Determining the priority of water-solar power consumption on the medium voltage side of the autotransformer includes: When the reservoir water level is below the permitted value, photovoltaic power generation is prioritized. The photovoltaic power on the medium voltage side operates at the maximum power generation capacity, and the power on the high voltage side satisfies formula (5). To avoid over-rated power on the high voltage side, the hydropower on the medium voltage side is adjusted according to the actual operation of the autotransformer. The output is reduced by the adjustment of the hydropower on the medium voltage side, and the difference is dynamically balanced by the hydropower on the high voltage side, so as to maintain the total hydropower output of the whole station unchanged within the given dispatching range. When the reservoir water level is above the permitted value, hydropower generation is prioritized. To avoid over-rated power on the high voltage side, the photovoltaic power on the medium voltage side determines the output upper limit according to the actual operation of the autotransformer.

5. The method according to claim 4, characterized in that The step of determining the priority of water-solar power consumption on the medium voltage side of the autotransformer further includes: (1)H≤H max Among them, H is the real-time water level of the hydropower station reservoir, H max Permitted water levels for hydropower station reservoirs; The photovoltaic power generation on the low-voltage side and medium-voltage side of the autotransformer is operated at the maximum capacity, and the upper limit of the hydropower output on the medium-voltage side of the autotransformer is: When the photovoltaic output suddenly changes and increases, such as causing the real-time output of hydropower on the medium-voltage side of the autotransformer P 2水 ≥P 2水 max , medium-pressure side hydropower output reduction △P=P 2水 -P 2水 max , ensuring that the high-voltage side of the autotransformer does not exceed the rated capacity, and at the same time the hydropower on the high-voltage side increases the load according to △P to maintain the total hydropower output of the entire station within the given dispatching range; When the photovoltaic output suddenly changes and decreases, the real-time hydropower output on the medium-voltage side of the autotransformer does not need to be adjusted, and the total hydropower output of the entire station is maintained within the given dispatching range; (2)H≥H max The photovoltaic power generation on the low voltage side of the autotransformer and the hydropower generation on the medium voltage side are operated at their maximum capacity. The upper limit of the photovoltaic power generation on the medium voltage side of the autotransformer is: P 2光 max =P 1N -P 3光 -P 2水 +P 2线 (7) (3)H max Setting principles Taking into account the duration of the maximum photovoltaic output at noon, the flow time of the upstream hydropower station, and the storage capacity of the reservoir, the reservoir allowable water level H is set. max limit.

6. The method according to claim 5, characterized in that Calculate the power transferred on the high voltage side of the autotransformer, including:

7. A water-photovoltaic complementary new energy consumption maximization control system based on autotransformer, characterized in that: include: The first priority determination module is used to determine the water-solar consumption priority of the medium-voltage side and the low-voltage side of the autotransformer based on the information that the common winding of the autotransformer is not overloaded; The second priority determination module is used to determine the priority of water-solar consumption on the medium-voltage side of the autotransformer according to the water level information of the hydropower station reservoir; The photovoltaic absorption module is used to maximize photovoltaic absorption based on the regulation of water-solar absorption priority, and calculate the transmission power on the high-voltage side of the autotransformer.

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