CN109936164A - Optimal operation method of multi-energy power system based on analysis of complementary characteristics of power sources - Google Patents

Abstract

A kind of multiple-energy-source electric power system optimization operation method based on the analysis of power supply complementary characteristic of the invention, its main feature is that, it include: to establish to provide multiple forms of energy to complement each other in multiple-energy-source electric system to coordinate the complementary mechanisms of power generation, mathematical model based on complementary mechanisms building complementary index system and complementary demand, define renewable energy complementary power supply, it calculates with matching water power capacity ratio required in the renewable energy complementary power supply of the minimum target of complementary demand, the hierarchy optimization operation reserve of polyisocyanate mass-energy source current is formulated according to complementary index, the corresponding optimization object function of each optimization layer is solved using particle swarm algorithm, calculating can make complementary index be optimal corresponding polyisocyanate mass-energy source current in the output power value of day part, this method has science, rationally, simply, it is practical, it is able to ascend renewable energy Dissolve horizontal advantage.

Description

Optimal operation method of multi-energy power system based on analysis of complementary characteristics of power sources

technical field

The invention relates to the field of optimal operation of electric power systems, and is an optimal operation method of a multi-energy electric power system based on the analysis of complementary characteristics of power sources.

Background technique

With the outbreak of the energy crisis and the prominence of environmental pollution, the development and utilization of renewable energy has received unprecedented attention. However, due to the intermittent and fluctuating output power of wind power and photovoltaics, it brings certain challenges to the optimal operation of the power grid. , Through the complementary characteristics between heterogeneous power sources, the impact of wind power and photovoltaic grid connection can be weakened, which plays an important role in reducing environmental pollution, improving energy utilization, and ensuring the stable operation of the power system. Therefore, utilizing the space-time complementary characteristics between power sources is an important means to improve the capacity of renewable energy consumption.

Existing researches on the optimal operation of power systems with new energy include using energy storage to cope with the uncertainty of renewable energy and optimizing the power system, but do not consider the complementary characteristics of other power sources; some only consider two Or the complementary characteristics between the three power sources to optimize the power system for energy saving, and to optimize the power system on multiple time scales from the perspective of source-grid-load coordination, but there are fewer types of power sources to consider. The power system is optimized from the perspective of peak regulation of the power system. In the power system optimization involving multiple energy sources, the existing research fails to make good use of the complementary characteristics of multiple power sources to improve the consumption of renewable energy.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a scientific, reasonable, simple and practical method for optimizing the operation of a multi-energy power system based on the analysis of the complementary characteristics of the power source.

The technical solution adopted to realize the purpose of the present invention is a method for optimizing operation of a multi-energy power system based on the analysis of the complementary characteristics of the power supply, which is characterized in that it comprises the following steps:

1) Establish a complementary mechanism for multi-energy complementary and coordinated power generation in a multi-energy power system

① In a multi-energy power system, a variety of heterogeneous energy sources with different output power characteristics are included, which is a prerequisite for multi-energy complementary and coordinated power generation. The power supply complementary characteristic is based on the characteristics of mutual aid and mutual power generation between different heterogeneous energy sources. Formula (1) is used to express the power supply complementary characteristic as the characteristic that the output power of various power supplies meets the system load.

In the formula, is the load value of the multi-energy power system in the t-th period; is the output power value of the i-th thermal power unit in the multi-energy power system in the t-th period, i=1,2,3...N _th , N _th is the in-service thermal power unit in the multi-energy power system in the t-th period quantity; is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the multi-energy power system in the t-th period of the hydroelectric unit number of service; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine number of times; t=1, 2, 3...T, T is the number of time periods, Δt is the time step,

② Establish a complementary mechanism for multi-energy complementary and coordinated power generation in a multi-energy power system: based on the natural complementary characteristics of various power sources, relying on the good regulation capabilities of thermal power, gas power, and adjustable hydropower to stabilize wind power and photovoltaics. The fluctuation of the output power of resource-constrained power sources, making full use of clean renewable energy sources, reducing the proportion of thermal power in the power system, realizing the rational allocation of power system resources, and finally achieving a real-time balance between the total power generation and total load of the system. To optimize the operation purpose,

2) Constructing complementary index system and mathematical model of complementary demand respectively

①Build a complementary index system

The complementarity index is defined as the quantitative index of the complementary effect pursued by the multi-energy power system, that is, the direction of its optimization. Combined with the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system, it can improve the system's renewable energy consumption capacity and energy saving. From the perspective of efficiency enhancement, build a complementary index system,

A. Calculate the penetration rate index of renewable energy in the multi-energy power system

Define r _pe (t) as the ratio of the output power of the renewable energy source to the load in the t-th period of the multi-energy power system, which mainly reflects the status of the renewable energy source in the power system and the penetration rate of the output power of the renewable energy source. The larger the value is, the cleaner the multi-energy power system is. Formula (2) is used to calculate the penetration rate of renewable energy in the multi-energy power system.

In the formula, is the penetration rate index of renewable energy in the multi-energy power system, represents the output power value of the renewable energy power source in the multi-energy power system in the t-th period, represents the load value of the multi-energy power system in the t-th period, T is the number of periods, Δt is the time step, t=1, 2, 3...T,

B. Calculate the coal consumption index of thermal power

In a multi-energy power system, the smaller the coal consumption of thermal power, the better the economy and environmental protection of thermal power. Formula (3) is used to calculate the coal consumption index of thermal power units,

In the formula, a _i , bi , c _i are the three fuel consumption characteristic coefficients of the _ith thermal power unit, i=1, 2, 3...N _th , N _th is the thermal power in the t-th time period in the multi-energy power system The number of units in service, f _it is the coal consumption index of the i-th thermal power unit in the t-th period, P _th.it is the output power value of the i-th thermal power unit in the t-th period, t=1,2, 3...T, Δt is the time step, T is the number of time periods,

C. Calculate the fluctuation range index of the load borne by thermal power

In order to reduce the frequent changes of output power of thermal power units, reduce coal consumption and improve utilization efficiency, the fluctuation range of load borne by thermal power should be minimized. The standard deviation of load value is used to represent the fluctuation range of load, and formula (4) is used to calculate thermal power The fluctuation range index of the unit's load,

In the formula, δ _th is the fluctuation range index of the load borne by thermal power units in the multi-energy power system, t = 1, 2, 3...T, Δt is the time step, T is the number of time periods, is the load value borne by all thermal power in the multi-energy power system in the t-th period, is the average load of all thermal power in the multi-energy power system during T periods,

D. Use formula (5) to calculate the power generation of hydropower,

In the formula, W _H is the total power generation of all hydropower in the multi-energy power system in T periods; is the water consumption of the jth hydroelectric unit for power generation in the tth period, is the head height of the j-th hydroelectric unit in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period, η is the hydroelectric conversion efficiency ;t=1,2,3...T, Δt is the time step, T is the number of time periods,

E. Use formula (6) to calculate the water abandonment index of hydropower,

In the formula, ΔQ is the index of water abandonment of all hydropower in T periods, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in T periods, is the water consumption of the j-th hydroelectric unit in the t-th period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, j=1, 2, 3...N _hy , N _hy is The number of in-service hydropower units in the multi-energy power system in the t-th period,

②Construct a mathematical model describing the complementary requirements of multiple heterogeneous power sources

The complementary demand of multi-heterogeneous power supplies is defined as the degree of matching between the output powers of the various heterogeneous power supplies after complementing each other with the load within a certain period of time. The two elements in the complementary demand are the power supply and the load. quantified between the complementary demand index and the complementary demand index between the power source and the load,

A. Calculate the complementary demand indicators between various heterogeneous power sources

A1. Use formula (7) to calculate the rate of change of the output power of the power supply,

r _i ^t =(P _i ^t -P _i ^t-1 )/Δt, (7)

In the formula, r _i ^t is the rate of change of the output power of the i-th power supply in the t-1th period to the t-th period, P _i ^t is the output power value of the i-th power source in the t-th period, P _i ^{t -1} is the output power value of the i-th power supply in the t-1th period, i=1,2,3...n, n is the number of power supply types under investigation, t=1,2,3...T; Δt is the time step size, T is the total number of epochs,

A2. Use formula (8) to calculate the set of absolute values of the sum of the output power change rates of thermal power, hydropower, photovoltaic, and wind power in each period,

In the formula, S _s is the set of absolute values of the sum of the output power change rates of thermal power, hydropower, photovoltaic, and wind power in each time period of T, and β _t is the thermal power, hydropower, photovoltaic, and wind power in the t-1th time period. The absolute value of the sum of the output power change rates in the t-th period, is the output power change rate of thermal power from the t-1th period to the tth period, is the output power change rate of hydropower from the t-1th period to the tth period, is the rate of change of photovoltaic output power from the t-1th period to the tth period, is the output power change rate of wind power from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

A3. Use formula (9) to calculate the complementary demand index between various heterogeneous power sources,

In the formula, D _ss is the complementary demand index between various heterogeneous power sources in T periods, and β _t is the output power change of thermal power, hydropower, photovoltaic, and wind power from the t-1th period to the tth period. The absolute value of the sum of the rates, t=1,2,3...T, Δt is the time step, T is the number of time periods,

The smaller the value of the complementary demand index between various heterogeneous power sources, the stronger the mutual support between the wind-solar, hydro-thermal power sources in the time scale under investigation, that is, the better the complementary effect. The weaker the mutual support, the

B. Calculate the complementary demand index between the power supply and the load

B1. Use formula (10) to calculate the relative rate of change of the output power of the power supply,

In the formula, is the relative rate of change of the total output power of all power supplies from the t-1th period to the tth period, is the output power change rate of the total output power of all power sources from the t-1th period to the tth period, P _sc is the installed capacity of the generator sets in service in all power sources, T is the number of periods, t=1,2,3 ...T, Δt is the time step,

B2. Use formula (11) to calculate the relative rate of change of the load,

In the formula, is the relative change rate of the system load from the t-1th period to the tth period, P _lmax.T is the maximum load value in the T period, is the change rate of the system load from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

B3. Use formula (12) to calculate the set of absolute values of the sum of the relative change rates in each period between the output power of all power supplies and the system load,

In the formula, S _l is the set of absolute values of the relative rate of change in each period between the output power of all power supplies and the system load in T time periods, and α _t is the difference between the output power of the power supply and the system load at the t-th The absolute value of the sum of the relative rate of change from 1 period to the t period, is the relative rate of change of the total output power of all power supplies from the t-1th period to the tth period, is the relative change rate of the system load from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

B4. Use formula (13) to calculate the complementary demand index between the power supply and the load,

In the formula, D _sl is the complementary demand index between the power supply and the load of the multi-energy power system in T time periods, α _t is the difference between the output power of the power supply and the system load from the t-1th period to the tth period. The absolute value of the relative change rate of the time period and the sum, T is the number of time periods, t=1, 2, 3...T, Δt is the time step,

The smaller the value of the complementary demand index between the power source and the load, the more similar the change trend of the power source and the load in the investigated time scale; otherwise, the more different the change trend of the power source and the load,

The better the complementarity between power sources and between power sources and loads, the smaller the complementary demand, that is, the closer the complementary demand index value is to zero;

3) Define renewable energy complementary power sources

The renewable energy power sources that can meet the complementary needs after complementation are aggregated into one power source, which is defined as Renewable Energy Complementary Power Supply (RECPS). The main purpose of aggregation is to reduce the power fluctuation brought by wind and solar power to the multi-energy power system. The basic rule of aggregation is to meet the complementary needs of the system under the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system. Based on energy conservation and environmental protection, the renewable energy power sources are aggregated, and the hydropower capacity ratio is calculated to minimize the complementary demand. After the renewable energy complementary power source is formed, its output power can follow the load fluctuation. In a multi-energy power system , the renewable energy complementary power supply is regarded as a kind of power supply, and it operates optimally together with other conventional power supplies, and when the system load value remains unchanged, the output power of the renewable energy complementary power supply also remains unchanged;

4) Formulate a hierarchical optimization operation strategy for multi-heterogeneous energy power sources

The hierarchical optimization operation strategy of multi-heterogeneous energy power sources is based on the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system, giving priority to full acceptance of wind power and photovoltaic power generation; making full use of adjustable hydropower to deal with these uncertain power sources such as wind and solar. The randomness, intermittency and anti-peak regulation characteristics brought about by the present invention aggregate hydropower, wind power, and photovoltaics into a renewable energy complementary power supply. The output power of the renewable energy complementary power supply is relatively stable and can follow the load fluctuation, which can improve the multi-energy power supply. The ability of the system to absorb the wind and the wind and reduce the adverse impact of the uncertainty of wind and wind resources on the stable operation of the system,

The selected optimization objective of the multi-energy power system is to optimize the complementary indexes of the multi-energy power system and realize the rational allocation of power system resources. Including complementary power optimization layer, residual hydropower optimization layer, thermal power optimization layer,

①Complementary power optimization layer

In the optimization operation of the multi-energy power system, the renewable energy complementary power supply is firstly optimized, and the renewable energy complementary power supply is obtained by the aggregation of wind power, photovoltaic and hydropower. Obtain the aggregate capacity ratio of matching hydropower and wind power in the renewable energy complementary power supply, and then determine the output power of wind power, photovoltaic, and matching hydropower in each time period. The main goal of the renewable energy complementary power optimization layer is to determine the wind power, wind power The aggregate proportion of

In the formula, D _sl is the complementary demand between the power source and the load of the multi-energy power system in T time periods, is the relative rate of change of the load from the t-1th period to the tth period, is the relative change rate of the output power of the renewable energy complementary power supply from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

②Remaining hydropower optimization layer

The net load curve is obtained by subtracting the output power of the renewable energy complementary power supply from the load value of the multi-energy power system. Under the condition that the net load is stable, the residual hydropower is used to generate electricity with the goal of minimizing the amount of waste water, and is calculated by formula (15). The objective function of the minimum amount of water waste from hydropower,

In the formula, ΔQ is the discarded water volume of the remaining hydropower in T periods, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in T periods, is the water consumption of the jth hydroelectric unit in the tth period, j=1,2,3...N _rhy , N _rhy is the total number of remaining hydroelectric units, t=1,2,3...T, Δt is the time step , T is the number of time periods,

③ Thermal power optimization layer

The residual load is obtained by subtracting the residual hydropower output power from the net load curve. Under the dual action of the renewable energy complementary power supply and residual hydropower, the fluctuation range of the residual load is small, and the output power of the thermal power unit is arranged with the goal of minimum coal consumption. When the output power of the thermal power unit reaches the minimum, and the total output power of various heterogeneous power sources is still greater than the load, part of the output power of the renewable energy power source needs to be discarded, and formula (16) is used to calculate the objective function of the minimum coal consumption for thermal power generation,

In the formula, F is the total coal consumption of the thermal power unit, u _it is the on-off coefficient of thermal power, which is 1 when starting up and 0 when shutting down, f _it is the coal consumption of the i-th thermal power unit in the t-th period, i=1 ,2,3…N _th , N _th is the total number of thermal power units, t=1,2,3…T, Δt is the time step, T is the number of time periods,

5) Determine the constraints

The optimal operation of the multi-energy power system needs to satisfy the constraint equations of equations (17) to (23),

①Determine power balance constraints

The power balance constraint is expressed by Equation (17),

In the formula, is the total thermal power output power in the t-th period, is the remaining hydropower output power in the t-th period, is the total hydropower output power in the t-th period, is the total output power of the hydroelectric unit in the renewable energy complementary power supply in the t-th period, is the output power of the renewable energy complementary power supply in the t-th period, P _l ^t is the load value of the multi-energy power system in the t-th period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

② Determine the active output power constraints of the unit

The active output power constraint of the unit is expressed by formula (18),

In the formula, is the output power value of the i-th thermal power unit in the multi-energy power system in the t-th period, i=1,2,3...N _th , N _th is the in-service thermal power unit in the multi-energy power system in the t-th period quantity; is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the multi-energy power system in the t-th period of the hydroelectric unit number of service; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine P _max.i is the upper limit of the output power of the ith thermal power unit in the multi-energy power system, P _max.j is the upper limit of the output power of the j-th hydropower unit in the multi-energy power system, and P _max.k is the multi-energy power system. The upper limit of the output power of the kth photovoltaic unit in the power system, P _max.g is the upper limit of the output power of the gth wind turbine in the multi-energy power system; P _min.i is the output of the ith thermal power unit in the multi-energy power system. Power lower limit, P _min.j is the output power lower limit of the jth hydroelectric unit in the multi-energy power system, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

③ Determine the system spinning reserve capacity constraints

The system spinning reserve capacity constraint is expressed by formula (19),

where: is the spinning reserve capacity of the system in the t-th period, is the rotating reserve capacity of the i-th thermal power unit in the t-th period, i=1,2,3...N _th , where N _th is the number of thermal power units in service in the t-th period in the multi-energy power system; is the rotating reserve capacity of the j-th hydroelectric unit in the t-th period, j=1, 2, 3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period; α is The demand coefficient of the system load forecast error to the spinning reserve, β is the demand coefficient of the wind power output power prediction error to the spinning reserve; γ is the demand coefficient of the photovoltaic output power prediction error to the spinning reserve, is the load value of the multi-energy power system in the t-th period; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine number of times, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

④ Determine the up-slope constraint and down-slope constraint of the unit

The up-climbing constraints and down-climbing constraints of the unit are expressed by formulas (20)~(21),

P _i ^{t+1 -} P _i ^t ≤ΔP _i ^up (20)

P _i ^t -P _i ^t+1 ≤ΔP _i ^down (21)

In the formula, P _i ^t+1 is the output power of the i-th unit in the multi-energy power system in the t+1-th period, P _i ^t is the output power of the i-th unit in the multi-energy power system in the t-th period, ΔP _i ^up is the maximum value of the ith unit uphill in the multi-energy power system, ΔP _i ^down is the maximum value of the ith unit in the multi-energy power system downhill, i=1,2,3...N,N is the number of active units in the multi-energy power system, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

⑤ Determine the constraints of hydropower generation

The constraint of hydropower generation is expressed by formula (22),

where: is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period , W _H is the total power generation of all hydropower units in the multi-energy power system in T time periods, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

⑥ Determine hydroelectric flow constraints

The hydroelectric flow constraint is expressed by Equation (23),

In the formula: Q _jmin is the minimum allocated water consumption of the jth hydropower unit in the T period, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in the T period, is the water consumption of the j-th hydropower unit in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-power units of the multi-energy power system in the t-th period, t=1,2 ,3…T, Δt is the time step, T is the number of time periods,

6) Through steps 1) to 5), using the constructed complementary index system and the mathematical model of complementary demand, combined with the actual operation constraints of the multi-energy power system, the output power of the renewable energy complementary power source is most matched with the load, and the remaining The objective function of the minimum water waste of hydropower and the minimum coal consumption of thermal power is solved by particle swarm algorithm, and finally the output power value of the multi-heterogeneous energy power source in each time period can be calculated to optimize the complementary index.

The features of the method for optimizing operation of a multi-energy power system based on the analysis of the power supply complementary characteristics of the present invention include the following steps: first, establishing a complementary mechanism for multi-energy complementary and coordinated power generation in the multi-energy power system, and constructing a complementary mechanism based on the complementary mechanism Then, define the renewable energy complementary power source, which is composed of all wind and solar power sources and the required matching hydropower, and calculate the hydropower capacity ratio aiming at the minimum complementary demand; Secondly, the hierarchical optimization operation strategy of multi-heterogeneous energy power sources is formulated according to the complementary indicators, including the complementary power source optimization layer, the remaining hydropower optimization layer, and the thermal power optimization layer. Solve the problem and calculate the output power value of the multi-heterogeneous energy power source in each period that can make the complementary index reach the optimum. This method is scientific, reasonable, simple and practical, and can improve the level of renewable energy consumption. .

Description of drawings

1 is a flowchart of a method for optimizing operation of a multi-energy power system based on the analysis of complementary characteristics of power sources according to the present invention;

Figure 2 is a schematic diagram of the change curve of the complementary demand of the multi-energy power system with the aggregation ratio of hydropower and wind and solar power capacity;

Figure 3 is a comparison diagram of the output power and load of the renewable energy complementary power supply;

Figure 4 is a graph showing the results of the optimized operation of the multi-energy power system;

Figure 5 is a comparison chart of the power generation of various heterogeneous power sources before and after optimization.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and embodiments.

Referring to Figures 1-5, Figure 1 shows the basic data processing, the construction of the complementary index system and the mathematical model of complementary requirements to the formulation of the hierarchical optimization operation strategy for multi-heterogeneous energy power sources. Finally, the particle swarm algorithm is used for each optimization layer. The corresponding optimization objective function is solved, and the technical roadmap of the output power value of the multi-heterogeneous energy power source in each time period corresponding to the optimal complementarity index is calculated. Figure 3 shows the comparison between the output power and load of the optimized renewable energy complementary power supply; Figure 4 shows the results of the optimal operation of the multi-energy power system; Figure 5 shows the comparison of the power generation of various heterogeneous power sources before and after optimization.

In a method for optimizing operation of a multi-energy power system based on the analysis of the complementary characteristics of the power supply of the present invention, the parameter values of the embodiment are set as follows:

The parameters of the thermal power unit are shown in Table 1

Table 1 embodiment thermal power unit parameters

parameter TH1 TH2 TH3 TH4 TH5 Capacity (MW) 6020 270 270 1320 700 Maximum output power (MW) 6020 270 270 1320 700 Minimum output power (MW) 300 135 135 560 320 Ramp rate (MW/min) 10 2.7 2.7 6 7 a 0.0088 0.0028 0.0085 0.0022 0.0058 b 0.17 0.52 0.32 0.35 0.45 c 10.8 14.7 12.3 13.8 11.9

The total installed capacity of wind power is 1,920MW; the total installed capacity of photovoltaics is 7,954MW; Requirement coefficient for spinning reserve γ=9%; T=24; ΔT=1h.

A method for optimizing operation of a multi-energy power system based on the analysis of the complementary characteristics of the power supply of the present invention includes the following steps:

1) Establish a complementary mechanism for multi-energy complementary and coordinated power generation in a multi-energy power system

① In a multi-energy power system, a variety of heterogeneous energy sources with different output power characteristics are included, which is a prerequisite for multi-energy complementary and coordinated power generation. The power supply complementary characteristic is based on the characteristics of mutual aid and mutual aid power generation between different heterogeneous energy sources. Formula (1) is used to express the power supply complementary characteristic as the characteristic that the output power of various power sources meets the system load.

In the formula, is the load value of the multi-energy power system in the t-th period; is the output power value of the i-th thermal power unit in the multi-energy power system in the t-th period, i=1,2,3...N _th , N _th is the in-service thermal power unit in the multi-energy power system in the t-th period quantity; is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the multi-energy power system in the t-th period of the hydroelectric unit number of service; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine number of times; t=1, 2, 3...T, T is the number of time periods, Δt is the time step,

② Establish a complementary mechanism for multi-energy complementary and coordinated power generation in a multi-energy power system: based on the natural complementary characteristics of various power sources, relying on the good regulation capabilities of thermal power, gas power, and adjustable hydropower to stabilize wind power and photovoltaics. The fluctuation of the output power of resource-constrained power sources, making full use of clean renewable energy sources, reducing the proportion of thermal power in the power system, realizing the rational allocation of power system resources, and finally achieving a real-time balance between the total power generation and total load of the system. To optimize the operation purpose,

2) Constructing complementary index system and mathematical model of complementary demand respectively

①Build a complementary index system

The complementarity index is defined as the quantitative index of the complementary effect pursued by the multi-energy power system, that is, the direction of its optimization. Combined with the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system, it can improve the system's renewable energy consumption capacity and energy saving. From the perspective of efficiency enhancement, build a complementary index system,

A. Calculate the penetration rate index of renewable energy in the multi-energy power system

Define r _pe (t) as the ratio of the output power of the renewable energy source to the load in the t-th period of the multi-energy power system, which mainly reflects the status of the renewable energy source in the power system and the penetration rate of the output power of the renewable energy source. The larger the value is, the cleaner the multi-energy power system is. Formula (2) is used to calculate the penetration rate of renewable energy in the multi-energy power system.

In the formula, is the penetration rate index of renewable energy in the multi-energy power system, represents the output power value of the renewable energy power supply in the multi-energy power system in the t-th period, P _l ^t represents the load value of the multi-energy power system in the t-th period, T is the number of periods, Δt is the time step, t = 1,2,3…T,

B. Calculate the coal consumption index of thermal power

In a multi-energy power system, the smaller the coal consumption of thermal power, the better the economy and environmental protection of thermal power. Formula (3) is used to calculate the coal consumption index of thermal power units,

In the formula, a _i , bi , c _i are the three fuel consumption characteristic coefficients of the _ith thermal power unit, i=1, 2, 3...N _th , N _th is the thermal power in the t-th time period in the multi-energy power system The number of units in service, f _it is the coal consumption index of the i-th thermal power unit in the t-th period, P _th.it is the output power value of the i-th thermal power unit in the t-th period, t=1,2, 3...T, Δt is the time step, T is the number of time periods,

C. Calculate the fluctuation range index of the load borne by thermal power

In order to reduce the frequent changes of output power of thermal power units, reduce coal consumption and improve utilization efficiency, the fluctuation range of load borne by thermal power should be minimized. The standard deviation of load value is used to represent the fluctuation range of load, and formula (4) is used to calculate thermal power The fluctuation range index of the unit's load,

In the formula, δ _th is the fluctuation range index of the load borne by thermal power units in the multi-energy power system, t = 1, 2, 3...T, Δt is the time step, T is the number of time periods, is the load value borne by all thermal power in the multi-energy power system in the t-th period, is the average load of all thermal power in the multi-energy power system during T periods,

D. Use formula (5) to calculate the power generation of hydropower,

In the formula, W _H is the total power generation of all hydropower in the multi-energy power system in T periods; is the water consumption of the jth hydroelectric unit for power generation in the tth period, is the head height of the j-th hydroelectric unit in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period, η is the hydroelectric conversion efficiency ;t=1,2,3...T, Δt is the time step, T is the number of time periods,

E. Use formula (6) to calculate the water abandonment index of hydropower,

In the formula, ΔQ is the index of water abandonment of all hydropower in T periods, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in T periods, is the water consumption of the j-th hydroelectric unit in the t-th period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, j=1, 2, 3...N _hy , N _hy is The number of in-service hydropower units in the multi-energy power system in the t-th period,

②Construct a mathematical model describing the complementary requirements of multiple heterogeneous power sources

The complementary demand of multi-heterogeneous power supplies is defined as the degree of matching between the output powers of the various heterogeneous power supplies after complementing each other with the load within a certain period of time. The two elements in the complementary demand are the power supply and the load. quantified between the complementary demand index and the complementary demand index between the power source and the load,

A. Calculate the complementary demand indicators between various heterogeneous power sources

A1. Use formula (7) to calculate the rate of change of the output power of the power supply,

r _i ^t =(P _i ^t -P _i ^t-1 )/Δt, (7)

In the formula, r _i ^t is the rate of change of the output power of the i-th power supply in the t-1th period to the t-th period, P _i ^t is the output power value of the i-th power source in the t-th period, P _i ^{t -1} is the output power value of the i-th power supply in the t-1th period, i=1,2,3...n, n is the number of power supply types under investigation, t=1,2,3...T; Δt is the time step size, T is the total number of epochs,

A2. Use formula (8) to calculate the set of absolute values of the sum of the output power change rates of thermal power, hydropower, photovoltaic, and wind power in each period,

In the formula, S _s is the set of absolute values of the sum of the output power change rates of thermal power, hydropower, photovoltaic, and wind power in each time period of T, and β _t is the thermal power, hydropower, photovoltaic, and wind power in the t-1th time period. The absolute value of the sum of the output power change rates in the t-th period, is the output power change rate of thermal power from the t-1th period to the tth period, is the output power change rate of hydropower from the t-1th period to the tth period, is the rate of change of photovoltaic output power from the t-1th period to the tth period, is the output power change rate of wind power from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

A3. Use formula (9) to calculate the complementary demand index between various heterogeneous power sources,

In the formula, D _ss is the complementary demand index between various heterogeneous power sources in T periods, and β _t is the output power change of thermal power, hydropower, photovoltaic, and wind power from the t-1th period to the tth period. The absolute value of the sum of the rates, t=1,2,3...T, Δt is the time step, T is the number of time periods,

The smaller the value of the complementary demand index between various heterogeneous power sources, the stronger the mutual support between the wind-solar, hydro-thermal power sources in the time scale under investigation, that is, the better the complementary effect. The weaker the mutual support, the

B. Calculate the complementary demand index between the power supply and the load

B1. Use formula (10) to calculate the relative rate of change of the output power of the power supply,

In the formula, is the relative rate of change of the total output power of all power supplies from the t-1th period to the tth period, is the output power change rate of the total output power of all power sources from the t-1th period to the tth period, P _sc is the installed capacity of the generator sets in service in all power sources, T is the number of periods, t=1,2,3 ...T, Δt is the time step,

B2. Use formula (11) to calculate the relative rate of change of the load,

In the formula, is the relative change rate of the system load from the t-1th period to the tth period, P _lmax.T is the maximum load value in the T period, is the change rate of the system load from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

B3. Use formula (12) to calculate the set of absolute values of the sum of the relative change rates in each period between the output power of all power supplies and the system load,

In the formula, S _l is the set of absolute values of the relative rate of change in each period between the output power of all power supplies and the system load in T time periods, and α _t is the difference between the output power of the power supply and the system load at the t-th The absolute value of the sum of the relative rate of change from 1 period to the t period, is the relative rate of change of the total output power of all power supplies from the t-1th period to the tth period, is the relative change rate of the system load from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

B4. Use formula (13) to calculate the complementary demand index between the power supply and the load,

In the formula, D _sl is the complementary demand index between the power supply and the load of the multi-energy power system in T time periods, α _t is the difference between the output power of the power supply and the system load from the t-1th period to the tth period. The absolute value of the relative change rate of the time period and the sum, T is the number of time periods, t=1, 2, 3...T, Δt is the time step,

The smaller the value of the complementary demand index between the power source and the load, the more similar the change trend of the power source and the load in the investigated time scale; otherwise, the more different the change trend of the power source and the load,

The better the complementarity between power sources and between power sources and loads, the smaller the complementary demand, that is, the closer the complementary demand index value is to zero;

3) Define renewable energy complementary power sources

The renewable energy power sources that can meet the complementary needs after complementation are aggregated into one power source, which is defined as Renewable Energy Complementary Power Supply (RECPS). The main purpose of aggregation is to reduce the power fluctuation brought by wind and solar power to the multi-energy power system. The basic rule of aggregation is to meet the complementary needs of the system under the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system. Based on energy conservation and environmental protection, the renewable energy power sources are aggregated, and the hydropower capacity ratio is calculated to minimize the complementary demand. After the renewable energy complementary power source is formed, its output power can follow the load fluctuation. In a multi-energy power system , the renewable energy complementary power supply is regarded as a kind of power supply, and it operates optimally together with other conventional power supplies, and when the system load value remains unchanged, the output power of the renewable energy complementary power supply also remains unchanged;

4) Formulate a hierarchical optimization operation strategy for multi-heterogeneous energy power sources

The hierarchical optimization operation strategy of multi-heterogeneous energy power sources is based on the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system, giving priority to full acceptance of wind power and photovoltaic power generation; making full use of adjustable hydropower to deal with these uncertain power sources such as wind and solar. The randomness, intermittency and anti-peak regulation characteristics brought about by the present invention aggregate hydropower, wind power, and photovoltaics into a renewable energy complementary power supply. The output power of the renewable energy complementary power supply is relatively stable and can follow the load fluctuation, which can improve the multi-energy power supply. The ability of the system to absorb the wind and the wind and reduce the adverse impact of the uncertainty of wind and wind resources on the stable operation of the system,

The selected optimization objective of the multi-energy power system is to optimize the complementary indexes of the multi-energy power system and realize the rational allocation of power system resources. Including complementary power optimization layer, residual hydropower optimization layer, thermal power optimization layer,

①Complementary power optimization layer

In the optimization operation of the multi-energy power system, the renewable energy complementary power supply is firstly optimized, and the renewable energy complementary power supply is obtained by the aggregation of wind power, photovoltaic and hydropower. Obtain the aggregate capacity ratio of matching hydropower and wind power in the renewable energy complementary power supply, and then determine the output power of wind power, photovoltaic, and matching hydropower in each time period. The main goal of the renewable energy complementary power optimization layer is to determine the wind power, wind power The aggregate proportion of

In the formula, D _sl is the complementary demand between the power source and the load of the multi-energy power system in T time periods, is the relative rate of change of the load from the t-1th period to the tth period, is the relative change rate of the output power of the renewable energy complementary power supply from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

②Remaining hydropower optimization layer

The net load curve is obtained by subtracting the output power of the renewable energy complementary power supply from the load value of the multi-energy power system. Under the condition that the net load is stable, the residual hydropower is used to generate electricity with the goal of minimizing the amount of waste water, and is calculated by formula (15). The objective function of the minimum amount of water waste from hydropower,

In the formula, ΔQ is the discarded water volume of the remaining hydropower in T periods, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in T periods, is the water consumption of the jth hydroelectric unit in the tth period, j=1,2,3...N _rhy , N _rhy is the total number of remaining hydroelectric units, t=1,2,3...T, Δt is the time step , T is the number of time periods,

③ Thermal power optimization layer

The residual load is obtained by subtracting the residual hydropower output power from the net load curve. Under the dual action of the renewable energy complementary power supply and residual hydropower, the fluctuation range of the residual load is small, and the output power of the thermal power unit is arranged with the goal of minimum coal consumption. When the output power of the thermal power unit reaches the minimum, and the total output power of various heterogeneous power sources is still greater than the load, part of the output power of the renewable energy power source needs to be discarded, and formula (16) is used to calculate the objective function of the minimum coal consumption for thermal power generation,

In the formula, F is the total coal consumption of the thermal power unit, u _it is the on-off coefficient of thermal power, which is 1 when starting up and 0 when shutting down, f _it is the coal consumption of the i-th thermal power unit in the t-th period, i=1 ,2,3…N _th , N _th is the total number of thermal power units, t=1,2,3…T, Δt is the time step, T is the number of time periods,

5) Determine the constraints

The optimal operation of the multi-energy power system needs to satisfy the constraint equations of equations (17) to (23),

①Determine power balance constraints

The power balance constraint is expressed by Equation (17),

In the formula, is the total thermal power output power in the t-th period, is the remaining hydropower output power in the t-th period, is the total hydropower output power in the t-th period, is the total output power of the hydroelectric unit in the renewable energy complementary power supply in the t-th period, is the output power of the renewable energy complementary power supply in the t-th period, P _l ^t is the load value of the multi-energy power system in the t-th period, t=1, 2, 3...T, Δt is the time step, T is the number of periods,

② Determine the active output power constraints of the unit

The active output power constraint of the unit is expressed by formula (18),

In the formula, is the output power value of the i-th thermal power unit in the multi-energy power system in the t-th period, i=1,2,3...N _th , N _th is the in-service thermal power unit in the multi-energy power system in the t-th period quantity; is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the multi-energy power system in the t-th period of the hydroelectric unit number of service; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine P _max.i is the upper limit of the output power of the ith thermal power unit in the multi-energy power system, P _max.j is the upper limit of the output power of the j-th hydropower unit in the multi-energy power system, and P _max.k is the multi-energy power system. The upper limit of the output power of the kth photovoltaic unit in the power system, P _max.g is the upper limit of the output power of the gth wind turbine in the multi-energy power system; P _min.i is the output of the ith thermal power unit in the multi-energy power system. Power lower limit, P _min.j is the output power lower limit of the jth hydroelectric unit in the multi-energy power system, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

③ Determine the system spinning reserve capacity constraints

The system spinning reserve capacity constraint is expressed by formula (19),

where: is the spinning reserve capacity of the system in the t-th period, is the rotating reserve capacity of the i-th thermal power unit in the t-th period, i=1,2,3...N _th , where N _th is the number of thermal power units in service in the t-th period in the multi-energy power system; is the rotating reserve capacity of the j-th hydroelectric unit in the t-th period, j=1, 2, 3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period; α is The demand coefficient of the system load forecast error to the spinning reserve, β is the demand coefficient of the wind power output power prediction error to the spinning reserve; γ is the demand coefficient of the photovoltaic output power prediction error to the spinning reserve, is the load value of the multi-energy power system in the t-th period; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine number of times, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

④ Determine the up-slope constraint and down-slope constraint of the unit

The up-climbing constraints and down-climbing constraints of the unit are expressed by formulas (20)~(21),

P _i ^{t+1 -} P _i ^t ≤ΔP _i ^up (20)

P _i ^t -P _i ^t+1 ≤ΔP _i ^down (21)

In the formula, P _i ^t+1 is the output power of the i-th unit in the multi-energy power system in the t+1-th period, P _i ^t is the output power of the i-th unit in the multi-energy power system in the t-th period, ΔP _i ^up is the maximum value of the ith unit uphill in the multi-energy power system, ΔP _i ^down is the maximum value of the ith unit in the multi-energy power system downhill, i=1,2,3...N,N is the number of active units in the multi-energy power system, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

⑤ Determine the constraints of hydropower generation

The constraint of hydropower generation is expressed by formula (22),

where: is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period , W _H is the total power generation of all hydropower units in the multi-energy power system in T time periods, t=1, 2, 3...T, Δt is the time step, T is the number of time periods,

⑥ Determine hydroelectric flow constraints

The hydroelectric flow constraint is expressed by Equation (23),

In the formula: Q _jmin is the minimum allocated water consumption of the jth hydropower unit in the T period, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in the T period, is the water consumption of the j-th hydropower unit in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-power units of the multi-energy power system in the t-th period, t=1,2 ,3…T, Δt is the time step, T is the number of time periods,

6) Through steps 1) to 5), using the constructed complementary index system and the mathematical model of complementary demand, combined with the actual operation constraints of the multi-energy power system, the output power of the renewable energy complementary power source is most matched with the load, and the remaining The objective function of the minimum water waste of hydropower and the minimum coal consumption of thermal power is solved by particle swarm algorithm, and finally the output power value of the multi-heterogeneous energy power source in each time period can be calculated to optimize the complementary index.

Combined with the multi-energy power system optimization operation model, the particle swarm algorithm program is written. The parameters in the algorithm program are set as: the particle swarm size is 20, the number of iterations is 500 times, the particle motion speed range is [-10, 10], and the learning factor is set. is 2, the linear inertia weight is used, the maximum value is set to 0.9, and the minimum value is set to 0.4.

The results of the optimization operation verification using the multi-energy power system optimization operation method based on the analysis of the complementary characteristics of the power supply of the present invention show that the acceptance capacity of the power grid for the wind and solar grid connection is enhanced, the grid connection ratio of the renewable energy is increased, and the natural resource constraints are reduced. Based on the influence of uncontrollable power generation on the power grid, the proportion of renewable energy generation increased from 72.76% before optimization to 76.57%. It can also be seen from the optimized operation results that the mean square error of thermal power output power is reduced from 196.775MW to 22.56MW, which reduces the fluctuation of thermal power output power and reduces the start, stop and adjustment of thermal power.

The specific embodiment of the present invention has made a detailed description of the content of the present invention, but it is not limited to this embodiment, and any obvious changes made by those skilled in the art according to the inspiration of the present invention belong to the scope of the right protection of the present invention .

Claims (1)

1. a multi-energy power system optimization operation method based on power supply complementary characteristic analysis, is characterized in that, it comprises the following steps: 1) Establish a complementary mechanism for multi-energy complementary and coordinated power generation in a multi-energy power system ① In a multi-energy power system, a variety of heterogeneous energy sources with different output power characteristics are included, which is a prerequisite for multi-energy complementary and coordinated power generation. The power supply complementary characteristic is based on the characteristics of mutual aid and mutual power generation between different heterogeneous energy sources. Formula (1) is used to express the power supply complementary characteristic as the characteristic that the output power of various power supplies meets the system load. In the formula, is the load value of the multi-energy power system in the t-th period; is the output power value of the i-th thermal power unit in the multi-energy power system in the t-th period, i=1,2,3...N _th , N _th is the in-service thermal power unit in the multi-energy power system in the t-th period quantity; is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the multi-energy power system in the t-th period of the hydroelectric unit number of service; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine number of times; t=1, 2, 3...T, T is the number of time periods, Δt is the time step, ② Establish a complementary mechanism for multi-energy complementary and coordinated power generation in a multi-energy power system: based on the natural complementary characteristics of various power sources, relying on the good regulation capabilities of thermal power, gas power, and adjustable hydropower to stabilize wind power and photovoltaics. The fluctuation of the output power of resource-constrained power sources, making full use of clean renewable energy sources, reducing the proportion of thermal power in the power system, realizing the rational allocation of power system resources, and finally achieving a real-time balance between the total power generation and total load of the system. To optimize the operation purpose, 2) Constructing complementary index system and mathematical model of complementary demand respectively ①Build a complementary index system The complementarity index is defined as the quantitative index of the complementary effect pursued by the multi-energy power system, that is, the direction of its optimization. Combined with the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system, it can improve the system's renewable energy consumption capacity and energy saving. From the perspective of efficiency enhancement, build a complementary index system, A. Calculate the penetration rate index of renewable energy in the multi-energy power system Define r _pe (t) as the ratio of the output power of the renewable energy source to the load in the t-th period of the multi-energy power system, which mainly reflects the status of the renewable energy source in the power system and the penetration rate of the output power of the renewable energy source. The larger the value is, the cleaner the multi-energy power system is. Formula (2) is used to calculate the penetration rate of renewable energy in the multi-energy power system. In the formula, is the penetration rate index of renewable energy in the multi-energy power system, represents the output power value of the renewable energy power supply in the multi-energy power system in the t-th period, P _l ^t represents the load value of the multi-energy power system in the t-th period, T is the number of periods, Δt is the time step, t = 1,2,3…T, B. Calculate the coal consumption index of thermal power In a multi-energy power system, the smaller the coal consumption of thermal power, the better the economy and environmental protection of thermal power. Formula (3) is used to calculate the coal consumption index of thermal power units, In the formula, a _i , bi , c _i are the three fuel consumption characteristic coefficients of the _ith thermal power unit, i=1, 2, 3...N _th , N _th is the thermal power in the t-th time period in the multi-energy power system The number of units in service, f _it is the coal consumption index of the i-th thermal power unit in the t-th period, P _th.it is the output power value of the i-th thermal power unit in the t-th period, t=1,2, 3...T, Δt is the time step, T is the number of time periods, C. Calculate the fluctuation range index of the load borne by thermal power In order to reduce the frequent changes of output power of thermal power units, reduce coal consumption and improve utilization efficiency, the fluctuation range of load borne by thermal power should be minimized. The standard deviation of load value is used to represent the fluctuation range of load, and formula (4) is used to calculate thermal power The fluctuation range index of the unit's load, In the formula, δ _th is the fluctuation range index of the load borne by thermal power units in the multi-energy power system, t = 1, 2, 3...T, Δt is the time step, T is the number of time periods, is the load value borne by all thermal power in the multi-energy power system in the t-th period, is the average load of all thermal power in the multi-energy power system during T periods, D. Use formula (5) to calculate the power generation of hydropower, In the formula, W _H is the total power generation of all hydropower in the multi-energy power system in T periods; is the water consumption of the jth hydroelectric unit for power generation in the tth period, is the head height of the j-th hydroelectric unit in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period, η is the hydroelectric conversion efficiency ;t=1,2,3...T, Δt is the time step, T is the number of time periods, E. Use formula (6) to calculate the water abandonment index of hydropower, In the formula, ΔQ is the index of water abandonment of all hydropower in T periods, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in T periods, is the water consumption of the j-th hydroelectric unit in the t-th period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, j=1, 2, 3...N _hy , N _hy is The number of in-service hydropower units in the multi-energy power system in the t-th period, ②Construct a mathematical model describing the complementary requirements of multiple heterogeneous power sources The complementary demand of multi-heterogeneous power supplies is defined as the degree of matching between the output powers of the various heterogeneous power supplies after complementing each other with the load within a certain period of time. The two elements in the complementary demand are the power supply and the load. quantified between the complementary demand index and the complementary demand index between the power source and the load, A. Calculate the complementary demand indicators between various heterogeneous power sources A1. Use formula (7) to calculate the rate of change of the output power of the power supply, In the formula, is the output power change rate of the i-th power supply from the t-1th period to the t-th period, P _i ^t is the output power value of the i-th power source in the t-th period, and P _i ^t-1 is the i-th The output power value of the power supply in the t-1th period, i=1,2,3...n, n is the number of power supply types under investigation, t=1,2,3...T; Δt is the time step, T is the total time period, A2. Use formula (8) to calculate the set of absolute values of the sum of the output power change rates of thermal power, hydropower, photovoltaic, and wind power in each period, In the formula, S _s is the set of absolute values of the sum of the output power change rates of thermal power, hydropower, photovoltaic, and wind power in each time period of T, and β _t is the thermal power, hydropower, photovoltaic, and wind power in the t-1th time period. The absolute value of the sum of the output power change rates in the t-th period, is the output power change rate of thermal power from the t-1th period to the tth period, is the output power change rate of hydropower from the t-1th period to the tth period, is the rate of change of photovoltaic output power from the t-1th period to the tth period, is the output power change rate of wind power from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, A3. Use formula (9) to calculate the complementary demand index between various heterogeneous power sources, In the formula, D _ss is the complementary demand index between various heterogeneous power sources in T periods, and β _t is the output power change of thermal power, hydropower, photovoltaic, and wind power from the t-1th period to the tth period. The absolute value of the sum of the rates, t=1,2,3...T, Δt is the time step, T is the number of time periods, The smaller the value of the complementary demand index between various heterogeneous power sources, the stronger the mutual support between the wind-solar, hydro-thermal power sources in the time scale under investigation, that is, the better the complementary effect. The weaker the mutual support, the B. Calculate the complementary demand index between the power supply and the load B1. Use formula (10) to calculate the relative rate of change of the output power of the power supply, In the formula, is the relative rate of change of the total output power of all power supplies from the t-1th period to the tth period, is the output power change rate of the total output power of all power sources from the t-1th period to the tth period, P _sc is the installed capacity of the generator sets in service in all power sources, T is the number of periods, t=1,2,3 ...T, Δt is the time step, B2. Use formula (11) to calculate the relative rate of change of the load, In the formula, is the relative change rate of the system load from the t-1th period to the tth period, P _lmax.T is the maximum load value in the T period, is the change rate of the system load from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, B3. Use formula (12) to calculate the set of absolute values of the sum of the relative change rates in each period between the output power of all power supplies and the system load, In the formula, S _l is the set of absolute values of the relative rate of change in each period between the output power of all power supplies and the system load in T time periods, and α _t is the difference between the output power of the power supply and the system load at the t-th The absolute value of the sum of the relative rate of change from 1 period to the t period, is the relative rate of change of the total output power of all power supplies from the t-1th period to the tth period, is the relative change rate of the system load from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, B4. Use formula (13) to calculate the complementary demand index between the power supply and the load, In the formula, D _sl is the complementary demand index between the power supply and the load of the multi-energy power system in T time periods, α _t is the difference between the output power of the power supply and the system load from the t-1th period to the tth period. The absolute value of the relative change rate of the time period and the sum, T is the number of time periods, t=1, 2, 3...T, Δt is the time step, The smaller the value of the complementary demand index between the power source and the load, the more similar the change trend of the power source and the load in the investigated time scale; otherwise, the more different the change trend of the power source and the load, The better the complementarity between power sources and between power sources and loads, the smaller the complementary demand, that is, the closer the complementary demand index value is to zero; 3) Define renewable energy complementary power sources The renewable energy power sources that can meet the complementary needs after complementation are aggregated into one power source, which is defined as Renewable Energy Complementary Power Supply (RECPS). The main purpose of aggregation is to reduce the power fluctuation brought by wind and solar power to the multi-energy power system. The basic rule of aggregation is to meet the complementary needs of the system under the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system. Based on energy conservation and environmental protection, the renewable energy power sources are aggregated, and the hydropower capacity ratio is calculated to minimize the complementary demand. After the renewable energy complementary power source is formed, its output power can follow the load fluctuation. In a multi-energy power system , the renewable energy complementary power supply is regarded as a kind of power supply, and it operates optimally together with other conventional power supplies, and when the system load value remains unchanged, the output power of the renewable energy complementary power supply also remains unchanged; 4) Formulate a hierarchical optimization operation strategy for multi-heterogeneous energy power sources The hierarchical optimization operation strategy of multi-heterogeneous energy power sources is based on the complementary mechanism of multi-energy complementary and coordinated power generation in the multi-energy power system, giving priority to full acceptance of wind power and photovoltaic power generation; making full use of adjustable hydropower to deal with these uncertain power sources such as wind and solar. The randomness, intermittency and anti-peak regulation characteristics brought about by the present invention aggregate hydropower, wind power, and photovoltaics into a renewable energy complementary power supply. The output power of the renewable energy complementary power supply is relatively stable and can follow the load fluctuation, which can improve the multi-energy power supply. The ability of the system to absorb the wind and the wind and reduce the adverse impact of the uncertainty of wind and wind resources on the stable operation of the system, The selected optimization objective of the multi-energy power system is to optimize the complementary indexes of the multi-energy power system and realize the rational allocation of power system resources. Including complementary power optimization layer, residual hydropower optimization layer, thermal power optimization layer, ①Complementary power optimization layer In the optimization operation of the multi-energy power system, the renewable energy complementary power supply is firstly optimized, and the renewable energy complementary power supply is obtained by the aggregation of wind power, photovoltaic and hydropower. Obtain the aggregate capacity ratio of matching hydropower and wind power in the renewable energy complementary power supply, and then determine the output power of wind power, photovoltaic, and matching hydropower in each time period. The main goal of the renewable energy complementary power optimization layer is to determine the wind power, wind power The aggregate proportion of In the formula, D _sl is the complementary demand between the power source and the load of the multi-energy power system in T time periods, is the relative rate of change of the load from the t-1th period to the tth period, is the relative change rate of the output power of the renewable energy complementary power supply from the t-1th period to the tth period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, ②Remaining hydropower optimization layer The net load curve is obtained by subtracting the output power of the renewable energy complementary power supply from the load value of the multi-energy power system. Under the condition of ensuring the stability of the net load, the residual hydropower is used to generate electricity with the goal of minimizing the amount of waste water, and is calculated by formula (15). The objective function of the minimum amount of water waste from hydropower, In the formula, ΔQ is the discarded water volume of the remaining hydropower in T periods, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in T periods, is the water consumption of the jth hydroelectric unit in the tth period, j=1,2,3...N _rhy , N _rhy is the total number of remaining hydroelectric units, t=1,2,3...T, Δt is the time step , T is the number of time periods, ③ Thermal power optimization layer The residual load is obtained by subtracting the residual hydropower output power from the net load curve. Under the dual action of the renewable energy complementary power supply and residual hydropower, the fluctuation range of the residual load is small, and the output power of the thermal power unit is arranged with the goal of minimum coal consumption. When the output power of the thermal power unit reaches the minimum, and the total output power of various heterogeneous power sources is still greater than the load, part of the output power of the renewable energy power source needs to be discarded, and formula (16) is used to calculate the objective function of the minimum coal consumption for thermal power generation, In the formula, F is the total coal consumption of the thermal power unit, u _it is the on-off coefficient of thermal power, which is 1 when starting up and 0 when shutting down, f _it is the coal consumption of the i-th thermal power unit in the t-th period, i=1 ,2,3…N _th , N _th is the total number of thermal power units, t=1,2,3…T, Δt is the time step, T is the number of time periods, 5) Determine the constraints The optimal operation of a multi-energy power system needs to satisfy the constraint equations of equations (17) to (23), ①Determine power balance constraints The power balance constraint is expressed by Equation (17), In the formula, is the total thermal power output power in the t-th period, is the remaining hydropower output power in the t-th period, is the total hydropower output power in the t-th period, is the total output power of the hydroelectric unit in the renewable energy complementary power supply in the t-th period, is the output power of the renewable energy complementary power supply in the t-th period, P _l ^t is the load value of the multi-energy power system in the t-th period, t=1, 2, 3...T, Δt is the time step, T is the number of periods, ② Determine the active output power constraints of the unit The active output power constraint of the unit is expressed by formula (18), In the formula, is the output power value of the i-th thermal power unit in the multi-energy power system in the t-th period, i=1,2,3...N _th , N _th is the in-service thermal power unit in the multi-energy power system in the t-th period quantity; is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the multi-energy power system in the t-th period of the hydroelectric unit number of service; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , N _w is the multi-energy power system in the t-th period of the wind turbine P _max.i is the upper limit of the output power of the ith thermal power unit in the multi-energy power system, P _max.j is the upper limit of the output power of the j-th hydropower unit in the multi-energy power system, and P _max.k is the multi-energy power system. The upper limit of the output power of the kth photovoltaic unit in the power system, P _max.g is the upper limit of the output power of the gth wind turbine in the multi-energy power system; P _min.i is the output of the ith thermal power unit in the multi-energy power system. Power lower limit, P _min.j is the output power lower limit of the jth hydroelectric unit in the multi-energy power system, t=1, 2, 3...T, Δt is the time step, T is the number of time periods, ③ Determine the system spinning reserve capacity constraints The system spinning reserve capacity constraint is expressed by formula (19), where: is the spinning reserve capacity of the system in the t-th period, is the rotating reserve capacity of the i-th thermal power unit in the t-th period, i=1,2,3...N _th , where N _th is the number of thermal power units in service in the t-th period in the multi-energy power system; is the rotating reserve capacity of the j-th hydroelectric unit in the t-th period, j=1, 2, 3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period; α is The demand coefficient of the system load forecast error to the spinning reserve, β is the demand coefficient of the wind power output power prediction error to the spinning reserve; γ is the demand coefficient of the photovoltaic output power prediction error to the spinning reserve, is the load value of the multi-energy power system in the t-th period; is the output power value of the k-th photovoltaic unit in the multi-energy power system in the t-th period, k=1,2,3...N _pv , where N _pv is the output power of the photovoltaic unit in the t-th period of the multi-energy power system number of service; is the output power value of the g-th wind turbine in the multi-energy power system in the t-th period, g=1, 2, 3...N _w , where N _w is the output power of the multi-energy power system in the t-th period of the wind turbine The number of battles, t=1, 2, 3...T, Δt is the time step, T is the number of time periods, ④ Determine the up-slope constraint and down-slope constraint of the unit The up-climbing constraints and down-climbing constraints of the unit are expressed by formulas (20) to (21), P _i ^{t+1 -} P _i ^t ≤ΔP _i ^up (20) P _i ^t -P _i ^t+1 ≤ΔP _i ^down (21) In the formula, P _i ^t+1 is the output power of the i-th unit in the multi-energy power system in the t+1-th period, P _i ^t is the output power of the i-th unit in the multi-energy power system in the t-th period, ΔP _i ^up is the maximum value of the ith unit uphill in the multi-energy power system, ΔP _i ^down is the maximum value of the ith unit in the multi-energy power system downhill, i=1,2,3...N,N is the number of active units in the multi-energy power system, t=1, 2, 3...T, Δt is the time step, T is the number of time periods, ⑤ Determine the constraints of hydropower generation The constraint of hydropower generation is expressed by formula (22), where: is the output power value of the j-th hydroelectric unit in the multi-energy power system in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-electric units in the multi-energy power system in the t-th period , W _H is the total power generation of all hydropower units in the multi-energy power system in T periods, t=1, 2, 3...T, Δt is the time step, T is the number of periods, ⑥ Determine hydroelectric flow constraints The hydroelectric flow constraint is expressed by Equation (23), In the formula: Q _jmin is the minimum allocated water consumption of the jth hydropower unit in the T period, Q _jmax is the maximum allocated water consumption of the jth hydropower unit in the T period, is the water consumption of the j-th hydropower unit in the t-th period, j=1,2,3...N _hy , N _hy is the number of in-service hydro-power units of the multi-energy power system in the t-th period, t=1,2 ,3…T, Δt is the time step, T is the number of time periods, 6) Through the steps 1) to 5), using the constructed complementary index system and the mathematical model of complementary demand, combined with the actual operation constraints of the multi-energy power system, the output power of the renewable energy complementary power source is most matched with the load, and the remaining The objective function of the minimum water waste of hydropower and the minimum coal consumption of thermal power is solved by particle swarm algorithm, and finally the output power value of the multi-heterogeneous energy power source in each period that can make the complementary index reach the optimum is calculated.