Water-light complementary system load distribution method changing along with time and space

Abstract

The invention discloses a spatio-temporal change-following load distribution method for a water-optical complementary system, which comprises the following steps of: constructing a power supply side power balance model by taking two transmission capacity sections as a center, and determining the apparent power of a first transmission capacity section and the total output power of the whole plant according to the power supply side power balance model; according to the apparent power of the first transmission capacity section and the total output power of the whole plant, internal limiting conditions of the water-light complementary system are constructed; the method comprises the steps that the dead water level of a reservoir is set to be hmin, the normal storage level of the reservoir is set to be hmax, the reservoir control water level upper limit hup and the reservoir control water level lower limit hdown, the current reservoir water level h is obtained, the current reservoir water level h is compared with hmin, hdown, hup and hmax, and load distribution of the water-light complementary system is conducted according to the comparison result. And the stability of the total output of the water-light complementary system is ensured.

Description

Technical Field

[0001] The present invention belongs to the technical field of control optimization of multi - energy complementary systems, and relates to a method for load distribution of a water - light complementary system that follows spatio - temporal changes. Background Art

[0002] With the continuous increase in the installed capacity of new energy sources such as wind power and photovoltaic power, new energy sources have disadvantages such as randomness, intermittency, and non - storability, which directly affect the safe and stable operation of the power system. Therefore, other forms of energy with frequency regulation, peak shaving, and energy storage attributes are required to compensate for it to meet the requirements of grid dispatching. Multi - energy complementarity is one of the important ways to solve the problem of new energy consumption globally. However, the distributed multi - energy complementary systems mainly based on micro - grids abroad are different from the huge flexibility requirements of large - scale power generation and long - distance power grid transmission in China. In the southwestern region of China, combined with the local rich water energy resources, using the transmission lines of the existing power plants, giving play to the advantages of fast regulation speed and energy storage of hydropower units, effectively alleviating the impact of new energy output fluctuations on the power system, the development and construction of large - scale water - light - wind multi - energy complementary bases are imperative.

[0003] For a multi - energy complementary base with photovoltaic power stations of different voltage levels accessing a hydropower plant, a photovoltaic - hydropower - transmission power balance model is constructed. Fully considering the characteristics of the AGC device and the difficulties of large capacity, large units, and complex grid connection, the operating characteristics of photovoltaic power, hydropower, and the complementary system are analyzed, and the spatio - temporal change law of the daily load of the water - light complementary system is summarized, and the real - time output of each power plant is adjusted in the optimal way. However, no similar disclosure exists in the prior art. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above - mentioned disadvantages of the prior art, and provides a method for load distribution of a water - light complementary system that follows spatio - temporal changes. This method can maximize the acceptance of new energy in the water - light complementary system and ensure the stability of the total output of the water - light complementary system.

[0005] To achieve the above - mentioned purpose, the present invention discloses a method for load distribution of a water - light complementary system that follows spatio - temporal changes, including:

[0006] Constructing a power - side power balance model with two transmission capacity sections as the center, and determining the apparent power of the first transmission capacity section and the total plant output power according to the power - side power balance model;

[0007] Constructing the internal limiting conditions of the water - light complementary system according to the apparent power of the first transmission capacity section and the total plant output power;

[0008] Setting the dead water level of the reservoir as h min , the normal storage level of the reservoir as h max , and the upper limit of the reservoir control water level h up, the lower limit h of the reservoir control water level down , obtain the current reservoir water level h, and compare the current reservoir water level h with h min , h down , h up and h max for comparison, and perform load distribution of the water-light complementary system according to the comparison result.

[0009] Further, the apparent power S of the first transmission capacity section tr is:

[0010]

[0011] Wherein, Q tr is the reactive power of the coupling transformer, and P tr is the active power of the coupling transformer.

[0012] Further, the reactive power Q of the coupling transformer tr is:

[0013]

[0014] Wherein, Q h1_1 , Q h1_2 , ……, Q h1_n1 are the reactive powers of the No. 1, No. 2, ……, No. n1 hydro-generator sets connected to the coupling transformer; Q Qv1_1 , Q Qv1_2 , ……, Q Qv1_m1 are the reactive powers of the No. 1, No. 2, ……, No. m1 photovoltaic power station groups connected to the coupling transformer; Q c is the total reactive power of the transmission line before connecting to the coupling transformer; Q l1_1 , Q l1_2 , ……, Q l1_z1 are the reactive powers of the No. 1, No. 2, ……, No. z1 transmission lines before connecting to the coupling transformer;

[0015] The active power P of the coupling transformer tr is:

[0016]

[0017] Wherein, P h1_1 , P h1_2 , ……, P h1_n1 are the active powers of the No. 1, No. 2, ……, No. n1 hydro-generator sets connected to the coupling transformer; P pv1_1 , P pv1_2 , ……, P pv1_m1 are the active powers of the No. 1, No. 2, ……, No. m1 photovoltaic power station groups connected to the coupling transformer; P cThe total active power of the transmission line before connecting to the combined transformer; P l1_1 , P l1_2 , ……, P l1_z1 are the active power of transmission line No. 1, the active power of transmission line No. 2, ……, the active power of transmission line No. z1 before connecting to the combined transformer.

[0018] Furthermore, the total plant output power P out is:

[0019] P out = N1 = P a + P b + P c (7)

[0020] wherein, P a is the output power of transmission line No. 1 that is not connected to the combined transformer; P b is the output power of transmission line No. 2 that is not connected to the combined transformer, P c is the total active power of the transmission line before connecting to the combined transformer, and N1 is the total actual power generation of the whole station.

[0021] Furthermore, the internal limiting conditions of the water-light complementary system include the first transmission capacity section limit, the second transmission capacity section limit, the rated power and vibration area limit of the hydropower unit, and the water level and reservoir capacity limit.

[0022] Furthermore, the process of load distribution of the water-light complementary system according to the comparison result is as follows:

[0023] When h min ≤ h < h down , the hydropower load priority strategy is adopted to meet the requirements of reservoir operation, and the output of the photovoltaic power station is restricted to ensure that the first transmission capacity section and the second transmission capacity section do not exceed the limit;

[0024] When h up < h ≤ h max , the strategy of hydropower output following the photovoltaic load is adopted to respond to the power generation demand of the photovoltaic power station;

[0025] When h down ≤ h ≤ h up , the water-light complementary strategy following the spatio-temporal changes is adopted, the day mode and the night mode are selected according to the spatio-temporal dynamics, and the load distribution is carried out according to the selection result.

[0026] Furthermore, let the hydropower units (G h2_1 , ……, G h2_n2 ) be the No. 1 to No. 8 units, the hydropower units (G h1_1 , ……, G h1_n1 ) be the No. 9 unit and the No. 10 unit, and the photovoltaic power station group (G pv1_1 , ……, Gpv1_m1 ) is the virtual unit group No. 11, and the outgoing lines (l 1_1 , l 1_2 , ……, l 1_z1 ) are used as the outgoing Circuit C; in the daytime mode, the process of load distribution of the water-light complementary system is as follows:

[0027] S41) When in the daytime mode, units No. 1 to No. 9 all participate in AGC regulation, and units No. 10 and No. 11 do not participate in AGC regulation;

[0028] S42) Read the active power and reactive power of units No. 1 to No. 10 and the outgoing Circuit C, and calculate the apparent power S tr , S c ;

[0029] S43) Assume that in sunny days, the maximum active power of the photovoltaic power station group connected to the water-light complementary system is P M1 , the maximum reactive power is Q M1 , and the maximum apparent power is S M1 ; in cloudy days, the maximum active power of the photovoltaic power station group connected to the water-light complementary system is P M2 , the maximum reactive power is Q M2 , and the maximum apparent power is S M2 ; in rainy days, the maximum active power of the photovoltaic power station group connected to the water-light complementary system is P M3 , the maximum reactive power is Q M2 , and the maximum apparent power is S M3 ;

[0030] S44) Calculate the total actual power generation N1 of the whole station;

[0031] S45) According to Step 43), calculate the maximum limit S h1 of the sum of the active power and apparent power of Unit No. 9 and Unit No. 10; h1 ;

[0032] S46) When N1 ≤ L2, according to the daily weather forecast and light power prediction data, select the maximum limit P h1 of the sum of the active power of Unit No. 9 and Unit No. 10, calculate the upper limit P 9_max of the regulation load of Unit No. 9, and go to Step S47);

[0033] S47) Perform load distribution of the water-light complementary system according to the upper limit P 9_max of the regulation load of Unit No. 9;

[0034] S48) When N1 > L2, then calculate the upper limit W 1_max, then go to step S44), and re - perform AGC allocation for units 1 to 9.

[0035] Furthermore, in step S44), the total actual power generation of the whole station N1 is:

[0036]

[0037] where N2 * is the sum of the actual power generations of units 1 to 8 that do not participate in AGC regulation, and N2 + is the actual power generation of units 1 to 8 that participate in AGC regulation, and P h is the sum of the active powers of unit 9 and unit 10.

[0038] Furthermore, assume that on sunny days, P h does not exceed the fixed value L3; on cloudy days, P h does not exceed the fixed value L4; on rainy days, P h does not exceed the fixed value L5; assume that the limit value of the power factor of unit 9 and unit 10 is The limit apparent power of sending out C - circuit lines is S C * , and the rated capacity of the coupling transformer is S tr * , then in step S45), calculate the sum of the active powers of unit 9 and unit 10 P h1 and the maximum limit value S h1 of the sum of apparent powers as:

[0039]

[0040]

[0041] Furthermore, the process of step S47) is as follows:

[0042] S471) When P 9_max ≥P9 up and P9 < P 9_max , then units 1 to 9 are allocated AGC according to the equal - proportion of capacity + single - unit minimum load limit; when P 9_max ≥P9 up and P9≥P 9_max , then the load of unit 9 is limited to P 9_max , and the remaining target load is allocated by units 1 to 8 according to the equal - proportion of capacity.

[0043] S472) When P 9_max <P9 up , then unit 9 operates with a load of P2 up , which makes unit 10 shut down. After unit 10 shuts down, when Str When it is less than L1, the units No. 1 to No. 9 perform AGC allocation in proportion to their capacities; when S tr ≥ L1, according to the recalculated P 9_max1 ;

[0044] S473) When P 9_max1 ≥ P9 up and P9 ≥ P 9_max1 at this time, the load of unit No. 9 is limited to P 9_max1 , and the remaining target load is redistributed by units No. 1 to No. 8 for AGC;

[0045] S474) When P9 down < P 9_max1 ≤ P9 up at this time, the load of unit No. 9 passing through the vibration area is limited to P9 down , and the remaining target load is redistributed by units No. 1 to No. 8 for AGC..

[0046] The present invention has the following beneficial effects:

[0047] When the load distribution method of the water-light complementary system following spatio-temporal changes of the present invention is specifically operated, a power balance model on the power supply side is constructed with two transmission capacity sections as the center, and then considering the internal limiting conditions of the water-light complementary system, with the goal of maximizing the acceptance of new energy and the safe operation of the reservoir and units, the day mode and night mode are dynamically selected according to spatio-temporal changes, and the AGC load distribution scheme is executed according to the equal proportion of capacity + the minimum load limit of a single unit, which can meet the economic operation requirements of the water-light complementary system, effectively reduce the probability of overloading of the coupling transformer and the occurrence of light abandonment and water abandonment, maximize the acceptance of new energy in the water-light complementary system, ensure the smoothness of the total output of the water-light complementary system, meet the actual on-site requirements, and has wide practicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The accompanying drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0049] Figure 1 is a schematic diagram of the water-light complementary system;

[0050] Figure 2 is a flow chart of the water-light complementary load distribution strategy in the present invention;

[0051] Figure 3 is a flow chart of the AGC load distribution scheme of the water-light complementary system in the present invention;

[0052] Figure 4 is a flow chart of the method of the present invention. Detailed implementation manners

[0053] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part rather than all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0054] In the description of the present invention, it should be understood that the terms "include" and "comprise" indicate the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0055] It should also be understood that the terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include the plural forms.

[0056] It should be further understood that the term "and / or" used in the specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations. For example, A and / or B can represent three cases: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in the present invention generally represents an "or" relationship between the contextually related objects.

[0057] It should be understood that although the terms first, second, third, etc. may be used in the embodiments of the present invention to describe preset ranges, etc., these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from each other. For example, without departing from the scope of the embodiments of the present invention, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0058] Depending on the context, the word "if" as used herein can be interpreted as "when" or "while" or "in response to determining" or "in response to detecting". Similarly, depending on the context, the phrase "if determined" or "if detected (stated condition or event)" can be interpreted as "when determined" or "in response to determining" or "when detected (stated condition or event)" or "in response to detecting (stated condition or event)".

[0059] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components described and shown in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0060] Various schematic structural diagrams according to the disclosed embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, where for the purpose of clear expression, some details are enlarged and some details may be omitted. The shapes of various regions and layers shown in the figures and their relative sizes and positional relationships are merely exemplary. In practice, there may be deviations due to manufacturing tolerances or technical limitations, and those skilled in the art can design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0061] Embodiment 1

[0062] Reference Figure 1 And Figure 4 , the method for load distribution of the water-light complementary system following spatio-temporal changes according to the present invention includes the following steps:

[0063] 1) Construct a power-side power balance model with two transmission capacity sections as the center. Among them, the first transmission capacity section is the input-output power balance of the coupling transformer, and the second transmission capacity section is the total plant input-output power balance.

[0064] Reference Figure 1 , the specific process of step 1) is:

[0065] S11) The power balance equation of the first transmission capacity section is:

[0066]

[0067] Among them, P tr is the active power of the coupling transformer, P h1_1 , P h1_2 , ……, P h1_n1 are the active powers of the 1st, 2nd, ……, n1th hydro-generating units connected to the coupling transformer; P pv1_1 , P pv1_2 , ……, P pv1_m1The active power of No. 1, No. 2, ……, No. m1 of the photovoltaic power station group connected to the combined transformer; P c The total active power of the transmission line before connecting to the combined transformer; P l1_1 、P l1_2 、……、P l1_z1 The active power of No. 1, No. 2, ……, No. z1 of the transmission line before connecting to the combined transformer.

[0068] Then the reactive power balance equation corresponding to the first transmission capacity section is:

[0069]

[0070] Among them, Q tr Is the reactive power of the combined transformer; Q h1_1 、Q h1_2 、……、Q h1_n1 The reactive power of No. 1, No. 2, ……, No. n1 of the hydro-generator sets connected to the combined transformer; Q Qv1_1 、Q Qv1_2 、……、Q Qv1_m1 The reactive power of No. 1, No. 2, ……, No. m1 of the photovoltaic power station group connected to the combined transformer; Q c Is the total reactive power of the transmission line before connecting to the combined transformer; Q l1_1 、Q l1_2 、……、Q l1_z1 The reactive power of No. 1, No. 2, ……, No. z1 of the transmission line before connecting to the combined transformer.

[0071] The apparent power of the first transmission capacity section is:

[0072]

[0073] (8) The power balance equation of the second transmission capacity section is:

[0074]

[0075] P out =N1=P a +P b +P c (7)

[0076] Among them, P in Is the total input power of the whole plant; P out Is the total output power of the whole plant; P h2_1 、P h2_2 、……、P h2_n2 The output power of No. 1, No. 2, ……, No. n2 of the hydro-generator sets not connected to the combined transformer; P ais the output power of the No. 1 transmission line not connected to the combined transformer; P b is the output power of the No. 2 transmission line not connected to the combined transformer.

[0077] Ignoring the auxiliary power consumption and internal line losses, it can be known that:

[0078] P in = P out (8)

[0079] When the dispatching issues to the water-light complementary system, setting the AGC total load command N0 and the total actual power generation of the whole station N1, the adjusted load ΔN is:

[0080] ΔN = N0 - N1 (9).

[0081] 2) According to the transmission capacity section and the actual operating characteristics of the power supply side, the internal limiting conditions of the water-light complementary system are established;

[0082] In this embodiment, the limit conditions include the first transmission capacity section limit, the second transmission capacity section limit, the rated power and vibration area limit of the hydropower unit, and the water level and reservoir capacity limit.

[0083] Specifically, the load of the first transmission capacity section is not overloaded: setting the rated capacity of the first transmission capacity section as L1, then there is:

[0084] S tr <L1 (10)

[0085] The rated load of the second transmission capacity section is not overloaded. Setting the limit power of the second transmission capacity section as L2, the limit power of the outgoing line A as L A , the limit power of the outgoing line B as L B , the limit power of the outgoing line C as L C , the limit powers of the No. 1, No. 2,..., No. z1 transmission lines before connecting to the combined transformer as L l1_1 、L l1_2 、...、L l1_z1 , then there is:

[0086] L2 = L A + L B + L C (11)

[0087]

[0088] P out <L2 (13)

[0089] P A <L A (14)

[0090] PB <L B (15)

[0091]

[0092] Let the minimum output and maximum output of unit i be N i,min 、N i,max . For the rated power limit of the hydropower unit: the output F of unit i i shall satisfy:

[0093] N i,min <F i <N i,max (17)

[0094] Let the vibration area of unit i be [Ndown i, Nupi]. For the vibration area limit of the hydropower unit: the allowable operation area of unit i is:

[0095]

[0096] The allowable operation area of unit i is: [N i,min , Ndown i] ∪ [Nup i,, N i,max .

[0097] Let the adjustable water level in front of the dam be h, and let the dead water level of the reservoir be h min . Let the normal storage level be h max . The water level - storage capacity limit is:

[0098] h min ≤h≤h max (19).

[0099] 3) Set the upper and lower limits of the reservoir control water level h up 、h down , satisfying h min ≤h down ≤h up ≤h max , and perform the load distribution of the water - light complementary system;

[0100] Reference Figure 2 . The process of step 3) is:

[0101] S31) When the reservoir water level is at a high level or there is already a flood - discharge flow, that is, h min ≤h<h down , then adopt the hydropower load - priority strategy to meet the requirements of reservoir operation, and ensure that the first transmission capacity section and the second transmission capacity section do not exceed the limit by restricting the output of the photovoltaic power station;

[0102] S32) When the reservoir water level is at a low level, that is, h up<h ≤ h max If so, the strategy of hydropower output following the photovoltaic load is adopted to respond to the power generation demand of the photovoltaic power station, and the hydropower unit adjusts the load N w as follows:

[0103]

[0104] Let the load regulation dead zone of the hydropower unit be ΔN 0d , and the target load regulation difference be ΔN 0w1 : Subtract the target load at the previous moment from the target load at the current moment to obtain the actual load deviation ΔN 0w2 : Subtract the actual load at the current moment from the target load at the current moment; when ΔN 0w1 >ΔN 0d or ΔN 0w2 >ΔN 0d , then execute the load distribution algorithm according to the equal proportion distribution of the unit capacity + the minimum load regulation limit of a single unit;

[0105] S33) When h down ≤ h ≤ h up , then adopt the complementary strategy of water-light following the spatio-temporal variation, and select the day mode and night mode according to the spatio-temporal dynamics.

[0106] 4) As Figure 3 shown, let the hydropower units (G h2_1 , ……, G h2_n2 ) be Unit 1 to Unit 8, the hydropower units (G h1_1 , ……, G h1_n1 ) be Unit 9 and Unit 10, the photovoltaic power station group (G pv1_1 , ……, G pv1_m1 ) be Virtual Unit 11, and the outgoing lines (l 1_1 , l 1_2 , ……, l 1_z1 ) be the outgoing C circuits. Perform load distribution according to the load distribution method of the complementary system of water-light following the spatio-temporal variation. Specifically, judge the current mode. When it is the day mode, execute steps S41)-S48); when it is the night mode, execute step S49).

[0107] S41) When in the day mode, Units 1 to 9 participate in AGC regulation, Units 10 and 11 do not participate in AGC regulation, but are included in the total actual power generation value of the whole plant. Calculate the total active power P M , total reactive power Q M and total apparent power S M of the photovoltaic power station group currently connected to the complementary system of water-light as follows:

[0108]

[0109] S42) Read the active power and reactive power of Unit 1 to Unit 10 and outgoing Circuit C, and calculate the apparent power S of the coupling transformer and outgoing Circuit C tr 、S c ;

[0110] S43) Analyze the peak characteristics of PV output on typical days. Assume that on sunny days, the maximum active power of the PV power plant group connected to the water-light complementary system is P M1 , the maximum reactive power is Q M1 , and the maximum apparent power is S M1 ; On cloudy days, the maximum active power of the PV power plant group connected to the water-light complementary system is P M2 , the maximum reactive power is Q M2 , and the maximum apparent power is S M2 ; On rainy days, the maximum active power of the PV power plant group connected to the water-light complementary system is P M3 , the maximum reactive power is Q M2 , and the maximum apparent power is S M3 , where

[0111]

[0112] S44) The sum of the actual output powers of Unit 1 to Unit 8 not participating in AGC regulation is N2 * , the actual output power of Unit 1 to Unit 8 participating in AGC regulation is N2 + , and the sum of the active powers of Unit 9 and Unit 10 is P h , then there is

[0113]

[0114] S45) Assume that on sunny days, P h does not exceed the fixed value L3; on cloudy days, P h does not exceed the fixed value L4; on rainy days, P h does not exceed the fixed value L5. Assume that the limit of the power factor of Unit 9 and Unit 10 is The limit apparent power of outgoing Circuit C is S C * , and the rated capacity of the coupling transformer is S tr * . To avoid overloading of the coupling transformer, calculate the maximum limits P h1 、S h1 of the sum of the active powers and the sum of the apparent powers of Unit 9 and Unit 10 as follows:

[0115]

[0116] S46) When N1 ≤ L2, according to the day-ahead weather forecast and the predicted optical power data, select the maximum limit value P of the sum of the active power of Unit 9 and Unit 10 h1 , and calculate the upper limit of the adjustable load P of Unit 9 9_max as follows:

[0117]

[0118] S47) When ΔN 0w1 > ΔN 0d or ΔN 0w2 > ΔN 0d , the hydropower units perform the load distribution algorithm according to the equal proportion of capacity + the minimum load regulation limit of a single unit for load distribution;

[0119] The process of step S47) is as follows:

[0120] S471) When P 9_max ≥ P9 up and P9 < P 9_max , Units 1 to 9 perform AGC distribution according to the equal proportion of capacity + the minimum load limit of a single unit; when P 9_max ≥ P9 up and P9 ≥ P 9_max , the load of Unit 9 is limited to P 9_max , and the remaining target load is distributed by Units 1 to 8 according to the equal proportion of capacity.

[0121] S472) When P 9_max < P9 up , then Unit 9 operates with a load of P2 up , which causes Unit 10 to shut down. After Unit 10 shuts down, when S tr < L1, Units 1 to 9 perform AGC distribution according to the equal proportion of capacity. When S tr ≥ L1, a new P 9_max1 is obtained according to the recalculation.

[0122] S473) When P 9_max1 ≥ P9 up and P9 ≥ P 9_max1 , then the load of Unit 9 is limited to P 9_max1 , and the remaining target load is redistributed by Units 1 to 8 for AGC.

[0123] S474) When P9 down < P 9_max1 ≤ P9 up , then the load of Unit 9 passing through the vibration area is limited to P9 down , and the remaining target load is redistributed by Units 1 to 8 for AGC.

[0124] S48) When N1 > L2, calculate the upper limit of the target load W of Unit 1 to Unit 9 1_max , and after repeating steps S44) - S47), re - perform AGC allocation for Unit 1 to Unit 9, where

[0125] W 1_max = L2 - P 10 -P M (29)

[0126] S49) When the night mode is selected, Unit 1 to Unit 9 participate in AGC regulation, Unit 10 and Unit 11 do not participate in AGC regulation, but are included in the total actual power generation value of the whole plant. The regulation upper limit of Unit 2 is not set, and the output of the 11th virtual unit is 0; when any load regulation difference ΔN 0w1 、ΔN 0w2 exceeds the small - load regulation threshold, execute the load distribution algorithm of equal - proportion distribution according to capacity + minimum - load regulation limit of single unit for load distribution.

[0127] In this embodiment, the specific parameters of step S4) are: Unit 1 to Unit 9 hydropower units participate in AGC regulation, Unit 10 hydropower unit does not participate in AGC regulation, and all photovoltaic power station groups are regarded as the 11th virtual unit and do not participate in AGC regulation.

[0128] It should be noted that the present invention fully considers the limitations of factors such as the unit passing through the vibration area, reservoir capacity, and reservoir capacity. According to the characteristics of the power transmission capacity section on the power supply side, it deduces the power balance model of the water - light complementary system, constructs the input - output power balance equation of the combined transformer and the total input - output power balance equation; in order to avoid the phenomena of "abandoning water" and "abandoning light" as much as possible, it selects the hydropower load priority strategy, the hydropower output following the photovoltaic load strategy, and the water - light complementary strategy following the spatio - temporal changes according to the real - time water level of the reservoir; analyzes the peak characteristics of the output of the typical - day photovoltaic power station group, calculates the load limits of key units on sunny days, cloudy days, and rainy days, dynamically selects the day and night modes according to spatio - temporal changes, and executes AGC load distribution according to equal - proportion distribution according to capacity + minimum - load regulation limit of single unit, so as to ensure that the power transmission capacity section is not overloaded and maximize the acceptance of photovoltaic power generation.

[0129] Embodiment 2

[0130] The method for load distribution of the water - light complementary system following spatio - temporal changes according to the present invention includes:[[]]

[0131] The first construction module is used to construct a power balance model on the power supply side with two power transmission capacity sections as the center, and determine the apparent power of the first power transmission capacity section and the total output power of the whole plant according to the power balance model on the power supply side.

[0132] A second construction module, configured to construct internal constraint conditions of a water-light complementary system according to the apparent power of the first transmission capacity section and the total plant output power;

[0133] A distribution module, configured to set the dead water level of the reservoir as h min , the normal storage level of the reservoir as h max , the upper limit of the reservoir control water level h up , the lower limit of the reservoir control water level h down , obtain the current reservoir water level h, and compare the current reservoir water level h with h min , h down , h up and h max for comparison, and perform load distribution of the water-light complementary system according to the comparison result.

[0134] In the embodiments of the present application, the division of the modules is illustrative, merely a logical function division. In actual implementation, there may be other division methods. In addition, in each embodiment of the present application, each functional module may be integrated in a processor, may also exist physically alone, or two or more modules may be integrated in one module. The above integrated modules may be implemented in the form of hardware or in the form of software function modules.

[0135] Embodiment 3

[0136] A computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method for load distribution of a water-light complementary system that follows spatio-temporal changes. For example, it includes: constructing a power-side power balance model centered on two transmission capacity sections, determining the apparent power of the first transmission capacity section and the total plant output power according to the power-side power balance model; constructing internal constraint conditions of the water-light complementary system according to the apparent power of the first transmission capacity section and the total plant output power; setting the dead water level of the reservoir as h min , the normal storage level of the reservoir as h max , the upper limit of the reservoir control water level h up , the lower limit of the reservoir control water level h down , obtain the current reservoir water level h, and compare the current reservoir water level h with h min , h down , h up and h maxCompare and perform load distribution for the water-light complementary system according to the comparison results. Among them, the memory may include internal memory, such as high-speed random access memory, and may also include non-volatile memory, such as at least one disk memory, etc.; the processor, network interface, and memory are interconnected through an internal bus, and this internal bus can be an Industry Standard Architecture bus, a Peripheral Component Interconnect standard bus, an Extended Industry Standard Architecture bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. The memory is used to store programs. Specifically, the program can include program code, and the program code includes computer operation instructions. The memory can include internal memory and non-volatile memory and provide instructions and data to the processor.

[0137] Embodiment 4

[0138] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it implements the steps of the method for load distribution of the water-light complementary system following spatio-temporal changes. For example, it includes: constructing a power-side power balance model centered on two transmission capacity sections, and determining the apparent power of the first transmission capacity section and the total plant output power according to the power-side power balance model; constructing internal constraint conditions for the water-light complementary system according to the apparent power of the first transmission capacity section and the total plant output power; setting the dead water level of the reservoir as h min , the normal storage level of the reservoir as h max , the upper limit of the reservoir control water level h up , the lower limit of the reservoir control water level h down , obtaining the current reservoir water level h, and comparing the current reservoir water level h with h min , h down , h up and h max and perform load distribution for the water-light complementary system according to the comparison results. Specifically, the computer-readable storage medium includes but is not limited to, for example, volatile memory and / or non-volatile memory. The volatile memory can include random access memory and / or cache memory, etc. The non-volatile memory can include read-only memory, hard disk, flash memory, optical disc, magnetic disk, etc.

[0139] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media containing computer-usable program code.

[0140] This application is described with reference to the flowcharts and / or block diagrams of methods, apparatuses (systems), and computer program products according to embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate means for implementing the functions specified in one or more flows and / or blocks Figure 1 in one or more flows and / or blocks Figure 1 or in one or more blocks.

[0141] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, such that the instructions stored in the computer-readable memory generate a manufactured article including instruction means that implement the functions specified in one or more flows and / or blocks Figure 1 in one or more flows and / or blocks Figure 1 or in one or more blocks.

[0142] These computer program instructions can also be loaded onto a computer or other programmable data processing device, such that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process, and thus the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more flows and / or blocks Figure 1 in one or more flows and / or blocks Figure 1 or in one or more blocks.

[0143] Those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and the disclosure of the invention. This application is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include known common knowledge or conventional technical means in the technical field not disclosed by the present invention. The specification and embodiments are only regarded as exemplary, and the true scope and spirit of the present invention are pointed out by the following claims.

[0144] It should be understood that the present invention is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present invention is only limited by the appended claims.

[0145] The above are only the preferred embodiments of the present invention, and do not impose any limitations on the present invention. Any simple modifications, changes, and equivalent structural changes made to the above embodiments according to the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A load distribution method for a water-photovoltaic complementary system following time and space changes, characterized in that: include: A power balance model on the power supply side is constructed with two transmission capacity sections as the center, and the apparent power of the first transmission capacity section and the total output power of the whole plant are determined according to the power balance model on the power supply side; According to the apparent power of the first transmission capacity section and the total output power of the whole plant, the inherent constraints of the water-solar complementary system are constructed; Set the dead water level of the reservoir to h min , the normal water level of the reservoir is h max , the upper limit of reservoir water level control h up , reservoir control water level lower limit h down , obtain the current reservoir water level h, and compare the current reservoir water level h with h min 、h down 、h up and h max The comparison is made and the comparison result is used to decide the load distribution of the water-photovoltaic complementary system.

2. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 1 is characterized in that: The apparent power S of the first transmission capacity section tr for: Among them, Q tr is the combined transformer reactive power, P tr is the active power of the linked transformer.

3. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 2 is characterized in that: The combined reactive power Q tr for: Among them, Q h1_1 , Q h1_2 ,……,Q h1_n1 The reactive power of No. 1, No. 2, ..., and No. n1 of the hydropower units connected to the joint transformer; Q Qv1_1 , Q Qv1_2 ,……,Q Qv1_m1 The reactive power of the photovoltaic station group connected to the joint transformer No. 1, No. 2, ..., and No. m1; Q c is the total reactive power of the transmission line before connecting to the joint transformer; Q l1_1 , Q l1_2 ,……,Q l1_z1 It is the reactive power of transmission line No. 1, reactive power No. 2, ..., reactive power No. z1 before access to the joint transformer; The combined active power P tr for: Among them, P h1_1 , P h1_2 ,……,P h1_n1 is the active power of hydropower units No. 1, No. 2, ..., No. n1 connected to the joint transformer; P pv1_1 , P pv1_2 ,……,P pv1_m1 is the active power of PV station group 1, 2, ..., m1 connected to the joint transformer; P c is the total active power of the transmission line before connecting to the joint transformer; P l1_1 , P l1_2 ,……,P l1_z1 It is the active power of transmission line No. 1, active power No. 2, ..., active power No. z1 before access to the joint transformation.

4. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 1 is characterized in that: The total plant output power P out for: P out =N1=P a +P b +P c (7) Among them, P a is the output power of the No. 1 transmission line that is not connected to the joint transformer; P b is the output power of the No. 2 transmission line without the joint transformer, P c is the total active power of the transmission line before connecting to the joint transformer, and N1 is the total actual power of the whole station.

5. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 1 is characterized in that: The inherent restriction conditions of the water-photovoltaic complementary system include the first transmission capacity section restriction, the second transmission capacity section restriction, the rated power and vibration zone restriction of the hydropower unit and the water level storage capacity restriction.

6. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 1 is characterized in that: The process of distributing the load of the water-photovoltaic complementary system according to the comparison result is as follows: When h min ≤h<h down When the hydropower load priority strategy is adopted to meet the needs of reservoir scheduling, the output of photovoltaic stations is limited to ensure that the first transmission capacity section and the second transmission capacity section do not exceed the limit; When h up <h≤h max When the power output of hydropower follows the photovoltaic load, the strategy of hydropower output following photovoltaic load is adopted to respond to the power generation demand of photovoltaic stations; When h down ≤h≤h up When the water and light are complementary, the strategy of following the changes of time and space is adopted. The day mode and night mode are selected according to the time and space dynamics, and the load is distributed according to the selection results.

7. The load distribution method for a water-photovoltaic complementary system following time and space changes according to claim 6 is characterized in that: Hydropower unit (G h2_1 ,……,G h2_n2 ) are units 1 to 8, hydropower units (G h1_1 ,……,G h1_n1 ) for Unit 9 and Unit 10, and the photovoltaic station group (G pv1_1 ,……,G pv1_m1 ) is virtual machine group No. 11, sending line (l 1_1 , l 1_2 ,……,l 1_z1 ) as the sending C loop; in the daytime mode, the load distribution process of the water-solar complementary system is: S41) In the daytime mode, units 1 to 9 all participate in AGC regulation, while units 10 and 11 do not participate in AGC regulation; S42) Read the active power and reactive power of units 1 to 10 and the C-circuit output line, and calculate the apparent power S of the joint transformer and the C-circuit output line. tr , S c ; S43) When it is sunny, the maximum active power of the photovoltaic station group connected to the water-photovoltaic complementary system is P M1 , the maximum reactive power is Q M1 , the maximum apparent power is S M1 On cloudy days, the maximum active power of the photovoltaic station group connected to the water-photovoltaic complementary system is P M2 , the maximum reactive power is Q M2 , the maximum apparent power is S M2 ; On rainy days, the maximum active power of the photovoltaic station group connected to the water-photovoltaic complementary system is P M3 , the maximum reactive power is Q M2 , the maximum apparent power is S M3 ; S44) calculating the total actual power N1 of the whole station; S45) Calculate the sum of the active power P of the No. 9 unit and the No. 10 unit according to step 43) h1 The maximum limit of the sum of the apparent power S h1 ; S46) When N1≤L2, according to the weather forecast and optical power forecast data of the previous day, select the maximum limit P of the sum of the active power of units 9 and 10 h1 , calculate the upper limit of regulating load P of unit 9 9_max , and go to step S47); S47) According to the upper limit P of the load regulation of unit 9 9_max Carry out load distribution of water-photovoltaic complementary system; S48) When N1>L2, the target load upper limit W of units 1 to 9 is calculated. 1_max , then go to step S44) to reallocate AGC for units 1 to 9.

8. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 7 is characterized in that: In step S44), the total actual transmission power N1 of the entire station is: Among them, N2 * is the sum of the actual power of units 1 to 8 that do not participate in AGC regulation, N2 + is the actual power of units 1 to 8 participating in AGC regulation, P h It is the sum of the active power of Units 9 and 10.

9. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 7 is characterized in that: On a sunny day, P h Not exceeding the fixed value L3; on cloudy days, P h Not exceeding the fixed value L4; on rainy days, P h Not exceeding the set value L5; assuming that the power factor limit of units 9 and 10 is The maximum apparent power of the C loop is S C * , the rated capacity of the combined transformer is S tr * , then in step S45), the sum of the active powers of units 9 and 10 is calculated P h1 The maximum limit of the sum of the apparent power S h1 for:

10. The load distribution method of the water-photovoltaic complementary system following time and space changes according to claim 7, characterized in that: The process of step S47) is: S471) When P 9_max ≥P9 up And P9<P 9_max When P 9_max ≥P9 up And P9 ≥ P 9_max When the load limit of Unit 9 is P 9_max , then the remaining target load is distributed among units 1 to 8 in proportion to their capacities; S472) When P 9_max <P9 up , then unit 9 carries load P2 up If the unit 10 is shut down, then the unit 10 will be shut down. tr When <L1, AGC is allocated to units 1 to 9 in proportion to their capacities; when S tr ≥L1, recalculate P 9_max1 ; S473) When P 9_max1 ≥P9 up And P9 ≥ P 9_max1 When the load limit of Unit 9 is P 9_max1 , the remaining target load is redistributed by AGC from Units 1 to 8; S474) When P9 down <P 9_max1 ≤P9 up When the load of Unit 9 passing through the vibration zone is limited to P9 down , the remaining target load will be redistributed by AGC among units 1 to 8.

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