A new method for calculating peak-load gap in power system based on hydropower regulation

Abstract

The present invention discloses a peak-shaving gap calculation method for a new type of power system based on hydropower regulation. The method comprises the following steps: obtaining the calculation results of the water-wind-solar complementary operation boundary; constructing a water-wind-solar complementary optimization model within the section at a daily scale to obtain the optimization results of the water-wind-solar complementary optimization within the section; constructing a water-wind-solar complementary optimization model outside the section at a daily scale to obtain the optimization results of the water-wind-solar complementary optimization outside the section; constructing a thermal power regulation optimization model outside the section at a daily scale to calculate the peak-shaving gap of the power system based on the joint regulation of water, wind and solar. In the process of calculating the peak-shaving gap, the present invention simultaneously considers the nonlinear operation constraints of the hydropower station group developed in series or parallel and the complex boundary conditions of the power grid transmission limit, and can coordinate and optimize multiple types of power stations in the whole network, giving full play to the peak-shaving function of the regulating power station to promote the consumption of new energy sources of water, wind and solar.

Description

Technical Field

[0001] The present invention relates to the field of peak-shaving gap calculation of power systems, and in particular to a peak-shaving gap calculation method for a novel power system based on hydropower regulation. Background Art

[0002] The construction of power system peak load regulation capacity is the main measure to improve the power system regulation capacity and the key support to promote the large-scale and high-proportion development of new energy. Taking all factors into consideration, the accurate calculation of the peak load gap of the power system is the basis for improving the peak load regulation capacity of the power system.

[0003] At present, the peak-shaving gap calculation method at the power grid level is mainly aimed at power grids with thermal power as the main regulating power station. This method cannot adapt to the complex operation constraint model of hydropower. In addition, there is another method based on the calculation on the power generation side, which proposes a peak-shaving calculation method for a river basin or a cascade power station group. However, this method has not yet taken into account the complex cross-sectional constraints of the power grid and the coordinated peak-shaving effect with regulating power stations such as thermal power, resulting in the peak-shaving gap finally obtained with limited accuracy and lack of practicality. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the present invention provides a peak-shaving gap calculation method for a new power system based on hydropower regulation. During the peak-shaving gap calculation process, the nonlinear operating constraints of a group of hydropower stations developed in series or parallel and the complex boundary conditions of the power grid transmission limit are simultaneously considered, and coordinated optimization of multiple types of power stations in the entire network can be carried out to give full play to the peak-shaving function of the regulating power stations to promote the consumption of new energy sources such as water, wind and solar power.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0006] A method for calculating the peak-shaving gap of a new power system based on hydropower regulation comprises the following steps:

[0007] S1. Construct a water-wind-solar complementary operation boundary calculation model on an annual scale to obtain the calculation results of the water-wind-solar complementary operation boundary;

[0008] S2. According to the calculation result of the water-wind-solar complementarity operation boundary in step S1, a water-wind-solar complementarity optimization model within the section at the intra-day scale is constructed to obtain the optimization result of the water-wind-solar complementarity within the section;

[0009] S3. According to the optimization result of the water-wind-solar complementarity within the section in step S2, a water-wind-solar complementarity optimization model outside the section at the intra-day scale is constructed to obtain the optimization result of the water-wind-solar complementarity outside the section;

[0010] S4. According to the off-section hydro-wind-solar complementary optimization results in step S3, a daily-scale off-section thermal power regulation optimization model is constructed to calculate the peak-shaving gap of the power system based on the joint regulation of hydro-wind-solar.

[0011] Furthermore, step S1 includes the following steps:

[0012] S11. Construct the objective function of the water-wind-solar complementary operation on an annual scale;

[0013] S12. Construct a constraint model for the complementary operation of water, wind and solar power;

[0014] S13. The objective function of the water-wind-solar complementary operation in step S11 and the constraint model of the water-wind-solar complementary operation in step S12 are combined to construct a boundary calculation model of the water-wind-solar complementary operation on an annual scale to obtain the boundary calculation result of the water-wind-solar complementary operation.

[0015] Furthermore, step S11 includes the following steps:

[0016] S111. Construct the annual power generation objective function of the water-wind-solar complementary operation, expressed as:

[0017]

[0018] Where: E is the annual power generation target value of the hydro-wind-solar complementary operation, max is the maximum value function, i is the power station number, n is the power station number, j is the total number of power stations of the jth category, t is the time period number, T is the total number of time periods calculated in a year, j is the power station category number, m is the total number of power station categories, N j,it is the power output of the i-th power station in the j-th type of power station in the t-th period, m t is the number of hours in the tth period of the year;

[0019] S112. Construct the annual minimum output maximization objective function of the water-wind-solar complementary operation, expressed as;

[0020]

[0021] Among them: NP is the annual minimum output maximization target value of the hydro-wind-solar complementary operation, min is the minimum value function, It is the minimum output of the year for the complementary operation of water, wind and solar power;

[0022] S113. Set the annual power generation objective function of the water-wind-solar complementary operation in step S111 as the priority objective function, and set the annual minimum output maximization objective function of the water-wind-solar complementary operation in step S112 as the secondary objective function, so as to construct the objective function of the water-wind-solar complementary operation.

[0023] Further, step S12 includes the following steps:

[0024] S121. Construct a cross-section constraint model, expressed as:

[0025]

[0026] in: is the total power generation output of the hydropower station in section d in the tth period, d is the section identifier, in is the identifier in the section, t is the period number, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in period t, aout is the inter-provincial power transmission identifier, TC d is the transmission capacity of section d;

[0027] S122, constructing an operation constraint model of a hydropower station;

[0028] S123, constructing output constraint models of wind power stations and photovoltaic power stations;

[0029] S124, the section constraint model in step S121, the operation constraint model of the hydropower station in step S122, and the output constraint models of the wind power station and the photovoltaic power station in step S123 are combined to construct a constraint model for the complementary operation of water, wind and photovoltaic power stations.

[0030] Furthermore, in step S122, the hydropower station operation constraint model includes a water balance constraint model, a reservoir water level constraint model, a reservoir discharge flow constraint model, a hydropower station water quantity connection constraint model and a power station output constraint model.

[0031] Further, step S123 includes the following steps:

[0032] S1231. Calculate the maximum output of the wind power station and the photovoltaic power station, expressed as:

[0033]

[0034] in: is the maximum calculated output of the i-th wind power station in the t-th period, IC w,i is the installed capacity of the i-th wind power station, g i,t is the output coefficient of the i-th wind power station in the t-th period, is the calculated maximum output of the ith power station in the PV power station at the tth period, IC s,i is the installed capacity of the ith power station in the photovoltaic power station, f i,t is the output coefficient of the i-th power station in the photovoltaic power station in the t-th period;

[0035] S1232: According to the calculated outputs of the wind power station and the photovoltaic power station in step S1231, a wind and solar power output constraint model is constructed, which is expressed as:

[0036]

[0037] Where: N wi,t is the calculated output of the i-th wind power station in the t-th period, N si,t It is the calculated output of the i-th power station in the PV power station at the t-th time period.

[0038] Further, step S2 includes the following steps:

[0039] S21. Construct the intraday channel utilization objective function within the section, expressed as:

[0040]

[0041] Among them: U d is the target value of channel utilization rate within the daily section d, d is the section identifier, max is the maximum value function, t is the time period number, T is the total number of time periods calculated in a year, is the total power generation output of the hydropower station in section d in the tth period, in is the identifier of the section, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in the tth period, aout is the inter-provincial power transmission identifier, Δt is the length of the calculation period, TC d is the transmission capacity of section d;

[0042] S22. According to the calculation result of the water-wind-solar complementary operation boundary in step S1, a constraint model for optimizing the water-wind-solar complementary operation within the section is constructed;

[0043] S23. Combine the intra-day channel utilization objective function within the section in step S21 and the constraint model of water-wind-solar complementarity optimization within the section in step S22 to construct an intra-day scale intra-section water-wind-solar complementarity optimization model to obtain the intra-section water-wind-solar complementarity optimization result.

[0044] Further, step S22 includes the following steps:

[0045] S221. According to the calculation result of the hydro-wind-solar complementary operation boundary in step S1, a first storage capacity connection constraint model and a first electricity connection constraint model are constructed;

[0046] S222. Construct an optimization constraint model for a hydropower station, expressed as:

[0047] |Z i,end -Z i,begin |≤Z i,allow

[0048] Where: Z i,end is the end-of-day water level of the reservoir of the i-th power station in the hydropower station, Z i,begin is the initial water level of the reservoir of the i-th power station in the hydropower station, Z i,allow is the daily water level fluctuation allowed for the reservoir of the i-th power station in the hydropower station.

[0049] S223. The first storage capacity connection constraint model and the first electricity connection constraint model in step S221 and the optimization constraint model of the hydropower station in step S222 are combined to construct a constraint model for water-wind-solar complementarity optimization within the section.

[0050] Further, step S3 includes the following steps:

[0051] S31. Construct the peak-to-valley difference objective function of the residual load of water, wind and solar power outside the section, expressed as:

[0052]

[0053] Among them: F is the target value of the peak-to-valley difference of the residual load of water, wind and light outside the section during the day, min is the minimum value function, max is the maximum value function, Rt is the residual load in the tth period after wind, water and light regulation, Lt is the grid demand load in the tth period, N ain,t is the inter-provincial input power in the tth period, ain is the inter-provincial input identifier, d is the section identifier, D is the total number of sections, is the total power generation output of the hydropower station in section d in the tth period, in is the identifier of the section, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in period t, i is the power station number, n j is the total number of power stations of the jth category, j is the power station category number, m is the total number of power station categories, is the total power generation of the i-th power station in the j-th type of power station outside the section in the t-th period;

[0054] S32. According to the optimization result of the hydro-wind-solar complementarity in the section in step S2, a second storage capacity connection constraint model and a second power connection constraint model are constructed;

[0055] S33. The peak-to-valley difference objective function of the residual load of water, wind and solar power outside the section in step S31 and the second storage capacity connection constraint model and the second power connection constraint model in step S32 are combined to construct an optimization model of water, wind and solar power complementarity outside the section on a daily scale to obtain the optimization result of water, wind and solar power complementarity outside the section.

[0056] Further, step S4 includes the following steps:

[0057] S41. According to the optimization result of the hydro-wind-solar complementarity outside the section in step S3, the peak-to-valley difference objective function of the residual load of thermal power outside the section is constructed, which is expressed as:

[0058]

[0059] Among them: F' is the target value of the peak-to-valley difference of the residual load of thermal power outside the section during the day, min is the minimum value function, max is the maximum value function, R' t is the residual load in the tth period after thermal power regulation, R t is the residual load in the tth period after wind, water and light regulation, is the data in the optimization result of water, wind and light complementation outside the section, N coal,t is the power output of the coal-fired power plant in the tth period, N gas,t is the power generation output of the gas turbine power plant in the tth period;

[0060] S42. Construct a constraint model for off-section thermal power regulation at the intra-day scale;

[0061] S43. Combine the objective function of the peak-to-valley difference of the residual load of the thermal power outside the section in step S41 and the constraint model of the thermal power regulation outside the section at the intra-day scale in step S42 to construct an optimization model of the thermal power regulation outside the section at the intra-day scale, so as to calculate the peak-shaving gap of the power system based on the combined regulation of water, wind and solar power.

[0062] The beneficial effects of the present invention are:

[0063] The present invention constructs an annual-scale water-wind-solar complementary operation boundary calculation model to obtain the water-wind-solar complementary operation boundary calculation results, and then constructs a daily-scale in-section water-wind-solar complementary optimization model according to the water-wind-solar complementary operation boundary calculation results to obtain the in-section water-wind-solar complementary optimization results, and then constructs an intra-day scale out-section water-wind-solar complementary optimization model according to the intra-section water-wind-solar complementary optimization results to obtain the out-section water-wind-solar complementary optimization results, and finally constructs an intra-day scale out-section thermal power regulation optimization model according to the out-section water-wind-solar complementary optimization results to calculate the peak-shaving gap of the power system based on the joint regulation of water, wind and solar. In the peak-shaving gap calculation process, the nonlinear operation constraints of the hydropower station groups developed in series or parallel and the complex boundary conditions of the power grid transmission limit are considered simultaneously, and coordinated optimization of multiple types of power stations in the whole network can be carried out to give full play to the peak-shaving function of the regulating power station to promote the consumption of new energy sources of water, wind and solar. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 The figure is a flow chart of a peak-shaving gap calculation method for a new type of power system based on hydropower regulation. DETAILED DESCRIPTION

[0065] The specific implementation modes of the present invention are described below so that those skilled in the art can understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific implementation modes. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the attached claims, these changes are obvious, and all inventions and creations utilizing the concept of the present invention are protected.

[0066] like Figure 1 As shown, a peak-shaving gap calculation method for a new power system based on hydropower regulation includes steps S1-S4, which are specifically as follows:

[0067] S1. Construct a water-wind-solar complementary operation boundary calculation model on an annual scale to obtain the calculation results of the water-wind-solar complementary operation boundary.

[0068] In an optional embodiment of the present invention, the present invention combines the objective function of the water-wind-solar complementary operation with the constraint model of the water-wind-solar complementary operation, and constructs a water-wind-solar complementary operation boundary calculation model on an annual scale to obtain the water-wind-solar complementary operation boundary calculation result.

[0069] Step S1 includes the following steps:

[0070] S11. Construct the objective function of the complementary operation of water, wind and solar power on an annual scale.

[0071] Step S11 includes the following steps:

[0072] S111. Construct the annual power generation objective function of the water-wind-solar complementary operation, expressed as:

[0073]

[0074] Where: E is the annual power generation target value of the hydro-wind-solar complementary operation, max is the maximum value function, i is the power station number, n is the power station number, j is the total number of power stations of the jth type, t is the time period number, T is the total number of time periods calculated in a year (with ten days as the calculation period, T =36), j is the power station category number, m is the total number of power station categories, m=3, j=1 represents a wind farm, j=2 represents a photovoltaic power station, j=3 represents a hydropower station, N j,it is the power output of the i-th power station in the j-th type of power station in the t-th period, m t is the number of hours in the tth period of the year.

[0075] The present invention calculates the power generation output of the i-th power station in the hydropower station in the t-th time period, which is expressed as:

[0076] N h,it =Q h,it ×k / δ h,i

[0077] Where: N h,it is the power output of the i-th power station in the hydropower station in the t-th period, h is the hydropower station identifier, Q h,it is the power generation flow of the i-th power station in the hydropower station at the t-th period, δ h,i is the water consumption rate of the ith power station in the hydropower station, which varies with the water level of the reservoir. k is the conversion coefficient. If the unit of electricity is kWh, then k=3600.

[0078] S112. Construct the annual minimum output maximization objective function of the water-wind-solar complementary operation, expressed as;

[0079]

[0080] Among them: NP is the annual minimum output maximization target value of the hydro-wind-solar complementary operation, min is the minimum value function, It is the minimum output of the year for the complementary operation of water, wind and solar power.

[0081] S113. Set the annual power generation objective function of the water-wind-solar complementary operation in step S111 as the priority objective function, and set the annual minimum output maximization objective function of the water-wind-solar complementary operation in step S112 as the secondary objective function, so as to construct the objective function of the water-wind-solar complementary operation.

[0082] S12. Construct a constraint model for the complementary operation of water, wind and solar power.

[0083] Step S12 includes the following steps:

[0084] S121. Construct a cross-section constraint model, expressed as:

[0085]

[0086] in: is the total power generation output of the hydropower station in section d in the tth period, d is the section identifier, in is the identifier in the section, t is the period number, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in period t, aout is the inter-provincial power transmission identifier, TC d is the transmission capacity of section d.

[0087] S122. Construct an operation constraint model of the hydropower station.

[0088] The hydropower station operation constraint model includes water balance constraint model, reservoir water level constraint model, reservoir discharge flow constraint model, hydropower station water quantity connection constraint model and hydropower station output constraint model.

[0089] The present invention constructs a water balance constraint model, which is expressed as:

[0090]

[0091] Where: V i,t+1 is the reservoir water storage capacity of the i-th power station at the end of the t-th period, V i,t is the reservoir water storage capacity of the i-th power station at the beginning of the t-th period, R i,t is the inflow flow of the i-th power station in the hydropower station at the t-th period, Q ri,t is the discharge flow of the ith power station in the hydropower station in the tth period, Δt is the length of the calculation period, Q h,it is the power generation flow of the i-th power station in the hydropower station at the t-th period, S i,t is the water discharge of the i-th power station in the hydropower station at the t-th period.

[0092] The present invention constructs a reservoir water level constraint model, which is expressed as:

[0093]

[0094] in: is the minimum water level allowed in the reservoir of the i-th power station in the hydropower station in the t-th period, Z i,t is the water level of the reservoir of the i-th power station in the hydropower station at the t-th period, It is the maximum water storage level allowed in the reservoir of the i-th power station in the hydropower station in the t-th period.

[0095] The present invention constructs a reservoir discharge flow constraint model, which is expressed as:

[0096]

[0097] in: is the minimum discharge flow that the i-th power station in the hydropower station should guarantee in the t period, Q ri,t is the discharge flow of the ith power station in the hydropower station at the tth period, It is the maximum discharge flow that the i-th power station in the hydropower station should ensure in the t-th period.

[0098] The present invention constructs a water quantity connection constraint model for a hydropower station, which is expressed as:

[0099] R i,t =Q ri-1,t +I i,t

[0100] Where: R i,t is the inflow flow of the i-th power station in the hydropower station at the t-th period, Q ri-1,t is the discharge flow of the i-1th power station in the hydropower station at the tth period, I i,tIt is the average inflow from the i-1th power station to the i-th power station in the hydropower station during the tth period.

[0101] The present invention constructs a hydropower station output constraint model, which is expressed as:

[0102]

[0103] in: is the minimum allowable output of the i-th power station in the hydropower station in the t-th period, N h,it is the power output of the i-th power station in the hydropower station at the t-th period, It is the maximum allowable output of the i-th power station in the hydropower station in the t-th period.

[0104] S123. Construct output constraint models for wind power stations and photovoltaic power stations.

[0105] Step S123 includes the following steps:

[0106] S1231. Calculate the maximum output of the wind power station and the photovoltaic power station, expressed as:

[0107]

[0108] in: is the maximum calculated output of the i-th wind power station in the t-th period, IC w,i is the installed capacity of the i-th wind power station, g i,t is the output coefficient of the i-th wind power station in the t-th period, is the calculated maximum output of the ith power station in the PV power station at the tth period, IC s,i is the installed capacity of the ith power station in the photovoltaic power station, f i,t is the output coefficient of the i-th power station in the photovoltaic power station in the t-th period.

[0109] S1232: According to the calculated outputs of the wind power station and the photovoltaic power station in step S1231, a wind and solar power output constraint model is constructed, which is expressed as:

[0110]

[0111] Where: N wi,t is the calculated output of the i-th wind power station in the t-th period, N si,t It is the calculated output of the i-th power station in the PV power station at the t-th time period.

[0112] S124, the section constraint model in step S121, the operation constraint model of the hydropower station in step S122, and the output constraint models of the wind power station and the photovoltaic power station in step S123 are combined to construct a constraint model for the complementary operation of water, wind and photovoltaic power stations.

[0113] S13. The objective function of the water-wind-solar complementary operation in step S11 and the constraint model of the water-wind-solar complementary operation in step S12 are combined to construct a boundary calculation model of the water-wind-solar complementary operation on an annual scale to obtain the boundary calculation result of the water-wind-solar complementary operation.

[0114] S2. According to the calculation results of the water-wind-solar complementarity operation boundary in step S1, a water-wind-solar complementarity optimization model within the section at the intra-day scale is constructed to obtain the water-wind-solar complementarity optimization results within the section.

[0115] In an optional embodiment of the present invention, the present invention constructs a constraint model for optimizing water-wind-solar complementarity within a section based on the calculation results of the water-wind-solar complementarity operation boundaries, combines the constraint model for optimizing water-wind-solar complementarity within a section with the intra-day channel utilization objective function within the section, and constructs an intra-day scale water-wind-solar complementarity optimization model within the section to obtain the optimization results of water-wind-solar complementarity within the section.

[0116] Step S2 includes the following steps:

[0117] S21. Construct the intraday channel utilization objective function within the section, expressed as:

[0118]

[0119] Among them: U d is the target value of channel utilization rate within the daily section d, d is the section identifier, max is the maximum value function, t is the time period number, T is the total number of time periods calculated in a year, is the total power generation output of the hydropower station in section d in the tth period, in is the identifier of the section, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in the tth period, aout is the inter-provincial power transmission identifier, Δt is the length of the calculation period, TC d is the transmission capacity of section d.

[0120] S22. According to the calculation result of the water-wind-solar complementary operation boundary in step S1, a constraint model for optimizing the water-wind-solar complementary operation within the section is constructed.

[0121] Step S22 includes the following steps:

[0122] S221. According to the calculation result of the hydro-wind-solar complementary operation boundary in step S1, a first storage capacity connection constraint model and a first electricity connection constraint model are constructed.

[0123] The present invention constructs a first reservoir capacity connection constraint model according to the calculation result of the water-wind-solar complementary operation boundary in step S1, which is expressed as:

[0124] |V i,end -V i,begin |=V i,allow if rc i =1

[0125] Where: V i,begin is the initial storage capacity of the i-th power station in the hydropower station, V i,end is the end-of-day storage capacity of the i-th power station in the hydropower station, V i,allow is the daily regulation storage capacity of the i-th power station in the hydropower station, is the data in the boundary calculation results of the water-wind-solar complementary operation, rc i is the regulating capacity value of the i-th power station in the hydropower station. The regulating capacity of the power station at or above the season is 1, otherwise it is 0.

[0126] The present invention constructs a first power connection constraint model according to the calculation result of the hydro-wind-solar complementary operation boundary in step S1, which is expressed as:

[0127]

[0128] Where: I d is the total number of hydropower stations in section d, is the daily electricity of the ith hydropower station in section d obtained by medium- and long-term calculations, is the data in the boundary calculation results of the water-wind-solar complementary operation, is the daily electricity consumption of the i-th hydropower station in section d.

[0129] S222. Construct an optimization constraint model for a hydropower station, expressed as:

[0130] |Z i,end -Z i,begin |≤Z i,allow

[0131] Where: Z i,end is the end-of-day water level of the reservoir of the i-th power station in the hydropower station, Z i,begin is the initial water level of the reservoir of the i-th power station in the hydropower station, Z i,allow is the daily water level fluctuation allowed for the reservoir of the i-th power station in the hydropower station;

[0132] S223. The first storage capacity connection constraint model and the first electricity connection constraint model in step S221 and the optimization constraint model of the hydropower station in step S222 are combined to construct a constraint model for water-wind-solar complementarity optimization within the section.

[0133] S23. Combine the intra-day channel utilization objective function within the section in step S21 and the constraint model of water-wind-solar complementarity optimization within the section in step S22 to construct an intra-day scale intra-section water-wind-solar complementarity optimization model to obtain the intra-section water-wind-solar complementarity optimization result.

[0134] S3. According to the optimization result of water-wind-solar complementarity within the section in step S2, a water-wind-solar complementarity optimization model outside the section at the intra-day scale is constructed to obtain the optimization result of water-wind-solar complementarity outside the section.

[0135] In an optional embodiment of the present invention, the present invention constructs a second storage capacity connection constraint model and a second electricity connection constraint model according to the optimization results of the hydro-wind-solar complementarity within the section, and combines the peak-to-valley difference objective function of the hydro-wind-solar daily residual load outside the section, the second storage capacity connection constraint model and the second electricity connection constraint model to construct an optimization model of hydro-wind-solar complementarity outside the section at an intra-day scale to obtain the optimization results of hydro-wind-solar complementarity outside the section.

[0136] Step S3 includes the following steps:

[0137] S31. Construct the peak-to-valley difference objective function of the residual load of water, wind and solar power outside the section, expressed as:

[0138]

[0139] Where: F is the target value of the peak-to-valley difference of the residual load of the water, wind and solar power outside the section during the day, min is the minimum value function, max is the maximum value function, R t is the residual load in the tth period after wind, water and light regulation, L t is the grid demand load in the tth period, N ain,t is the inter-provincial input power in the tth period, ain is the inter-provincial input identifier, d is the section identifier, D is the total number of sections, is the total power generation output of the hydropower station in section d in the tth period, in is the identifier of the section, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in period t, i is the power station number, n j is the total number of power stations of the jth category, j is the power station category number, m is the total number of power station categories, is the total power generation of the i-th power station in the j-th type of power station outside the section in the t-th period;

[0140] S32. According to the optimization result of the hydro-wind-solar complementarity in the section in step S2, a second storage capacity connection constraint model and a second power connection constraint model are constructed;

[0141] According to the optimization result of water-wind-solar complementarity in the section in step S2, the present invention constructs a second reservoir capacity connection constraint model, which is expressed as:

[0142] |V i,end -V i,begin |=V′ i,allow if rc i =1

[0143] Where: V i,begin is the initial storage capacity of the i-th power station in the hydropower station, V i,end is the end-of-day storage capacity of the ith power station in the hydropower station, V′ i,allow is the optimized daily regulation storage capacity of the i-th power station in the hydropower station, is the data in the optimization result of water-wind-solar complementary in the section, rc i is the regulating capacity value of the i-th power station in the hydropower station. The regulating capacity of the power station at or above the season is 1, otherwise it is 0.

[0144] The present invention constructs a second power connection constraint model according to the calculation result of the hydro-wind-solar complementary operation boundary in step S1, which is expressed as:

[0145]

[0146] Where: I d is the total number of hydropower stations in section d, is the optimized daily power of the ith hydropower station in the d section obtained by medium- and long-term calculations, is the data in the optimization results of the water-wind-solar complementary optimization in the section, is the daily electricity consumption of the i-th hydropower station in section d.

[0147] S33. The peak-to-valley difference objective function of the residual load of water, wind and solar power outside the section in step S31 and the second storage capacity connection constraint model and the second power connection constraint model in step S32 are combined to construct an optimization model of water, wind and solar power complementarity outside the section on a daily scale to obtain the optimization result of water, wind and solar power complementarity outside the section.

[0148] S4. According to the off-section hydro-wind-solar complementary optimization results in step S3, a daily-scale off-section thermal power regulation optimization model is constructed to calculate the peak-shaving gap of the power system based on the joint regulation of hydro-wind-solar.

[0149] In an optional embodiment of the present invention, the present invention constructs an objective function of the peak-to-valley difference of the thermal power residual load during the day outside the section according to the optimization result of the complementary power of water, wind and solar power outside the section, and combines the objective function of the peak-to-valley difference of the thermal power residual load during the day outside the section with the constraint model of the thermal power regulation outside the section on a daily scale to construct an optimization model of the thermal power regulation outside the section on a daily scale, so as to calculate the peak-shaving gap of the power system based on the joint regulation of water, wind and solar power.

[0150] Step S4 includes the following steps:

[0151] S41. According to the optimization result of the hydro-wind-solar complementarity outside the section in step S3, the peak-to-valley difference objective function of the residual load of thermal power outside the section is constructed, which is expressed as:

[0152]

[0153] Among them: F' is the target value of the peak-to-valley difference of the residual load of thermal power outside the section during the day, min is the minimum value function, max is the maximum value function, R' t is the residual load in the tth period after thermal power regulation, R t is the residual load in the tth period after wind, water and light regulation, is the data in the optimization result of water, wind and light complementation outside the section, N coal,t is the power output of the coal-fired power plant in the tth period, N gas,t is the power output of the gas turbine power plant in period t.

[0154] S42. Construct a constraint model for off-section thermal power regulation at the intra-day scale.

[0155] The constraint models for off-section thermal power regulation at the daily scale include power balance constraint model and thermal power output constraint model. The thermal power output constraint model includes technical output constraint model, ramp rate constraint model and coal-fired unit start-stop constraint model.

[0156] In the present invention, the power load of the power system is provided by the hydropower, wind and solar power stations within the section, the hydropower, wind and solar power stations outside the section and the thermal power stations outside the section, and the load of the power system also includes inter-provincial input and output power, wherein the inter-provincial output power is provided by the power stations within the section. Therefore, the present invention constructs a power balance constraint model, which is expressed as:

[0157]

[0158] Where: L t is the grid demand load in the tth period, N ain,t is the inter-provincial input power in the tth period, ain is the inter-provincial input identifier, d is the section identifier, D is the total number of sections, is the total power generation output of the hydropower station in section d in the tth period, in is the identifier of the section, t is the period number, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in the tth period, aout is the inter-provincial power transmission identifier, i is the power station number, n j is the total number of power stations of the jth type, j is the power station category number, m is the total number of power station categories, m=3, j=1 represents a wind farm, j=2 represents a photovoltaic power station, j=3 represents a hydropower station, is the total power generation of the i-th power station in the j-th type power station outside the section at the t-th time period, N coal,t is the power output of the coal-fired power plant in the tth period, N gas,t is the power generation output of the gas turbine power plant in the tth period, N ps,tis the power generation output of the pumped storage power station in the tth period, which can be positive or negative. When the value is positive, it means that the pumped storage power station is generating electricity. When the value is negative, it means that the pumped storage power station is pumping water. N cs,t It is the power generation output of the chemical energy storage power station in the tth period, which can be positive or negative. When the value is positive, it means that the chemical energy storage power station is discharging, and when the value is negative, it means that the chemical energy storage power station is charging.

[0159] The technical output constraint model is expressed as:

[0160]

[0161] in: is the minimum power generation output of coal-fired power in the tth period, N coal,t is the power output of the coal-fired power plant in period t, is the maximum power generation output of coal-fired power in the tth period, is the minimum power output of the gas turbine power plant in the tth period, N gas,t is the power output of the gas turbine power plant in period t, It is the maximum power output of the gas turbine power plant in the tth period.

[0162] The climbing rate constraint model is expressed as:

[0163]

[0164] Where: N coal,t+1 is the power generation output of the coal-fired power plant in the t+1 period, N coal,t is the power output of the coal-fired power plant in period t, RU coal is the ramp-up rate of coal-fired power, RD coal is the down-ramp rate of coal-fired power, N gas,t+1 is the power generation output of the gas turbine power plant in the t+1 period, N gas,t is the power output of the gas turbine power plant in period t, RU gas is the ramp rate of the gas turbine power plant, RD gas is the ramp down rate of the gas turbine power station.

[0165] N coal,t is the power output of the coal-fired power plant in the tth period, N gas,t is the power generation output of the gas turbine power plant in the tth period, N ps,t is the power generation output of the pumped storage power station in the tth period, which can be positive or negative. When the value is positive, it means that the pumped storage power station is generating electricity. When the value is negative, it means that the pumped storage power station is pumping water. N cs,t It is the power generation output of the chemical energy storage power station in the tth period, which can be positive or negative. When the value is positive, it means that the chemical energy storage power station is discharging, and when the value is negative, it means that the chemical energy storage power station is charging.

[0166] The start-stop constraint model of coal-fired units is expressed as:

[0167]

[0168] in: is the startup time of the kth coal-fired unit, is the minimum startup time of the kth coal-fired unit, is the shutdown time of the kth coal-fired unit, is the minimum shutdown time of the kth coal-fired unit.

[0169] S43. Combine the objective function of the peak-to-valley difference of the residual load of the thermal power outside the section in step S41 and the constraint model of the thermal power regulation outside the section at the intra-day scale in step S42 to construct an optimization model of the thermal power regulation outside the section at the intra-day scale, so as to calculate the peak-shaving gap of the power system based on the combined regulation of water, wind and solar power.

[0170] The target value of the peak-to-valley difference of the residual load of thermal power outside the section obtained by the present invention is the peak-shaving gap of the power system based on the joint regulation of water, wind and light.

[0171] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A method for calculating the peak-load gap of a new type of power system based on hydropower regulation, characterized in that: The following steps are involved: S1. Construct a water-wind-solar complementary operation boundary calculation model on an annual scale to obtain the calculation results of the water-wind-solar complementary operation boundary; S2. Construct a constraint model according to the calculation result of the water-wind-solar complementarity operation boundary in step S1, so as to construct an optimization model of water-wind-solar complementarity within the section at the intra-day scale, and then obtain the optimization result of water-wind-solar complementarity within the section; S3. Construct a constraint model according to the optimization result of the water-wind-solar complementarity within the section in step S2, so as to construct an optimization model of the water-wind-solar complementarity outside the section at the intra-day scale, and then obtain the optimization result of the water-wind-solar complementarity outside the section; S4. According to the optimization result of the hydro-wind-solar complementary power generation outside the section in step S3, a thermal power regulation optimization model outside the section at the intra-day scale is constructed to calculate the peak regulation gap of the power system based on the joint regulation of hydro-wind-solar power generation; Step S4 includes the following steps: S41. According to the optimization result of the hydro-wind-solar complementarity outside the section in step S3, the peak-to-valley difference objective function of the residual load of thermal power outside the section is constructed, which is expressed as: Among them: F' is the target value of the peak-to-valley difference of the residual load of thermal power outside the section during the day, min is the minimum value function, max is the maximum value function, R' t is the residual load in the tth period after thermal power regulation, R t is the residual load in the tth period after wind, water and light regulation, is the data in the optimization result of water, wind and light complementation outside the section, N coal,t is the power generation output of the coal-fired power plant in the tth period, N gas,t is the power generation output of the gas turbine power plant in the tth period; S42. Construct a constraint model for off-section thermal power regulation at the intra-day scale; S43. Combine the objective function of the peak-to-valley difference of the residual load of the thermal power outside the section in step S41 and the constraint model of the thermal power regulation outside the section at the intra-day scale in step S42 to construct an optimization model of the thermal power regulation outside the section at the intra-day scale, so as to calculate the peak-shaving gap of the power system based on the combined regulation of water, wind and solar power.

2. According to claim 1, a peak-shaving gap calculation method for a new type of power system based on hydropower regulation is characterized in that: Step S1 includes the following steps: S11. Construct the objective function of the water-wind-solar complementary operation on an annual scale; S12. Construct a constraint model for the complementary operation of water, wind and solar power; S13. The objective function of the water-wind-solar complementary operation in step S11 and the constraint model of the water-wind-solar complementary operation in step S12 are combined to construct a boundary calculation model of the water-wind-solar complementary operation on an annual scale to obtain the boundary calculation result of the water-wind-solar complementary operation.

3. The peak-shaving gap calculation method of a new type of power system based on hydropower regulation according to claim 2 is characterized in that: Step S11 includes the following steps: S111. Construct the annual power generation objective function of the water-wind-solar complementary operation, expressed as: Where: E is the annual power generation target value of the hydro-wind-solar complementary operation, max is the maximum value function, i is the power station number, n is the power station number, j is the total number of power stations of the jth category, t is the time period number, T is the total number of time periods calculated in a year, j is the power station category number, m is the total number of power station categories, N j,it is the power output of the i-th power station in the j-th type of power station in the t-th period, m t is the number of hours in the tth period of the year; S112. Construct the annual minimum output maximization objective function of the water-wind-solar complementary operation, expressed as; Among them: NP is the annual minimum output maximization target value of the hydro-wind-solar complementary operation, min is the minimum value function, It is the minimum output of the year for the complementary operation of water, wind and solar power; S113. Set the annual power generation objective function of the water-wind-solar complementary operation in step S111 as the priority objective function, and set the annual minimum output maximization objective function of the water-wind-solar complementary operation in step S112 as the secondary objective function, so as to construct the objective function of the water-wind-solar complementary operation.

4. According to claim 2, a method for calculating the peak-load gap of a new type of power system based on hydropower regulation is characterized in that: Step S12 includes the following steps: S121. Construct a cross-section constraint model, expressed as: in: is the total power generation output of the hydropower station in section d in the tth period, d is the section identifier, in is the identifier in the section, t is the period number, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in period t, aout is the inter-provincial power transmission identifier, TC d is the transmission capacity of section d; S122, constructing an operation constraint model of a hydropower station; S123, constructing output constraint models of wind power stations and photovoltaic power stations; S124, the section constraint model in step S121, the operation constraint model of the hydropower station in step S122, and the output constraint models of the wind power station and the photovoltaic power station in step S123 are combined to construct a constraint model for the complementary operation of water, wind and photovoltaic power stations.

5. The peak-shaving gap calculation method of a new type of power system based on hydropower regulation according to claim 4 is characterized in that: In step S122, the hydropower station operation constraint model includes a water balance constraint model, a reservoir water level constraint model, a reservoir discharge flow constraint model, a hydropower station water quantity connection constraint model and a power station output constraint model.

6. The peak-shaving gap calculation method of a new type of power system based on hydropower regulation according to claim 4 is characterized in that: Step S123 includes the following steps: S1231. Calculate the maximum output of the wind power station and the photovoltaic power station, expressed as: in: is the maximum calculated output of the i-th wind power station in the t-th period, IC w,i is the installed capacity of the i-th wind power station, g i,t is the output coefficient of the i-th wind power station in the t-th period, is the calculated maximum output of the ith power station in the PV power station at the tth period, IC s,i is the installed capacity of the ith power station in the photovoltaic power station, f i,t is the output coefficient of the i-th power station in the photovoltaic power station in the t-th period; S1232: According to the calculated outputs of the wind power station and the photovoltaic power station in step S1231, a wind and solar power output constraint model is constructed, which is expressed as: Where: N wi,t is the calculated output of the i-th wind power station in the t-th period, N si,t It is the calculated output of the i-th power station in the PV power station at the t-th time period.

7. The peak-shaving gap calculation method of a new type of power system based on hydropower regulation according to claim 1 is characterized in that: Step S2 includes the following steps: S21. Construct the intraday channel utilization objective function within the section, expressed as: Among them: U d is the target value of channel utilization rate within the daily section d, d is the section identifier, max is the maximum value function, t is the time period number, T is the total number of time periods calculated in a year, is the total power generation output of the hydropower station in section d in the tth period, in is the identifier of the section, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in the tth period, aout is the inter-provincial power transmission identifier, Δt is the length of the calculation period, TC d is the transmission capacity of section d; S22. According to the calculation result of the water-wind-solar complementary operation boundary in step S1, a constraint model for optimizing the water-wind-solar complementary operation within the section is constructed; S23. Combine the intra-day channel utilization objective function within the section in step S21 and the constraint model of water-wind-solar complementarity optimization within the section in step S22 to construct an intra-day scale intra-section water-wind-solar complementarity optimization model to obtain the intra-section water-wind-solar complementarity optimization result.

8. The peak-shaving gap calculation method of a new type of power system based on hydropower regulation according to claim 7 is characterized in that: Step S22 includes the following steps: S221. According to the calculation result of the hydro-wind-solar complementary operation boundary in step S1, a first storage capacity connection constraint model and a first electricity connection constraint model are constructed; S222. Construct an optimization constraint model for a hydropower station, expressed as: |From i,end -WITH i,begin |≤Z i,allow Where: Z i,end is the end-of-day water level of the reservoir of the i-th power station in the hydropower station, Z i,begin is the initial water level of the reservoir of the i-th power station in the hydropower station, Z i,allow is the daily water level fluctuation allowed for the reservoir of the i-th power station in the hydropower station; S223. The first storage capacity connection constraint model and the first electricity connection constraint model in step S221 and the optimization constraint model of the hydropower station in step S222 are combined to construct a constraint model for water-wind-solar complementarity optimization within the section.

9. The peak-shaving gap calculation method of a new type of power system based on hydropower regulation according to claim 1 is characterized in that: Step S3 includes the following steps: S31. Construct the peak-to-valley difference objective function of the residual load of water, wind and solar power outside the section, expressed as: Where: F is the target value of the peak-to-valley difference of the residual load of the water, wind and solar power outside the section during the day, min is the minimum value function, max is the maximum value function, R t is the residual load in the tth period after wind, water and light regulation, L t is the grid demand load in the tth period, N ain,t is the inter-provincial input power in the tth period, ain is the inter-provincial input identifier, d is the section identifier, D is the total number of sections, is the total power generation output of the hydropower station in section d in the tth period, in is the identifier of the section, is the power load in section d during the tth period, is the inter-provincial power transmission of section d in period t, i is the power station number, n j is the total number of power stations of the jth category, j is the power station category number, m is the total number of power station categories, is the total power generation of the i-th power station in the j-th type of power station outside the section in the t-th period; S32. According to the optimization result of the hydro-wind-solar complementarity in the section in step S2, a second storage capacity connection constraint model and a second power connection constraint model are constructed; S33. The peak-to-valley difference objective function of the residual load of water, wind and solar power outside the section in step S31 and the second storage capacity connection constraint model and the second power connection constraint model in step S32 are combined to construct an optimization model of water, wind and solar power complementarity outside the section on a daily scale to obtain the optimization result of water, wind and solar power complementarity outside the section.

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