CN115940220A - Dispatching method and power grid partition configuration method based on photovoltaic-mountain gravity energy storage combined power generation system - Google Patents

Abstract

The invention discloses a photovoltaic-mountain gravity energy storage combined power generation system-based scheduling method and a power grid partition configuration method, and belongs to the field of power facility and power grid optimization. The photovoltaic-mountain gravity energy storage combined power generation system comprises a photovoltaic power station and a mountain gravity energy storage device, and the scheduling method comprises the following steps: when the unbalanced electric quantity delta P (t) at the moment t is larger than 0, the mountain gravity energy storage device works in an energy storage mode to charge, and when the energy storage of the mountain gravity energy storage device reaches a capacity limit value, surplus electric quantity is sold to the main network through a PCC (point-of-charge controller) point; when the unbalanced electric quantity is less than 0, the output of the photovoltaic power station is insufficient, the mountain gravity energy storage device discharges in an energy release mode, and after the discharge electrode limit is reached, the insufficient electric quantity is purchased to the main network through a PCC (point-of-charge controller) point; a photovoltaic power station and gravity energy storage are combined to form a combined power generation system, and the problem of insufficient power supply of a power grid and users in a mountain area is solved by setting a scheduling strategy and a planning method.

Description

A dispatching method and grid partitioning configuration method based on photovoltaic-mountain gravity energy storage combined power generation system

Technical Field

The present invention relates to the field of power facilities and power grid optimization, and in particular to a scheduling method and a power grid zoning configuration method based on a photovoltaic-mountain gravity energy storage combined power generation system.

Background Art

With the prominence of the energy crisis, solar power generation has become an important development trend. In recent years, the installed capacity of household photovoltaic grid-connected has shown a rapid growth trend. On the other hand, gravity energy storage is a new energy storage technology that has received more and more attention in recent years. For the establishment of photovoltaic power stations in mountainous areas, although it can effectively solve the problem of insufficient power supply capacity of mountain power grids to mountain users, due to the randomness and volatility of household photovoltaics, as the proportion of photovoltaics continues to rise, this will have a significant impact on the safety, stability and economic operation of the distribution network, mainly reflected in the voltage limit of the grid, power reverse transmission and line overload. In addition, during the peak load period at night, photovoltaic power generation cannot be used, resulting in its inability to effectively solve the electricity consumption problem of mountain users. Reasonable installation of energy storage equipment to participate in grid dispatching can effectively solve this problem, but the cost of traditional energy storage devices and global communication of the grid is too high, resulting in a decline in economic efficiency.

Summary of the invention

In view of the above-mentioned defects of the prior art, the present invention provides a scheduling method and a grid zoning configuration method based on a photovoltaic-mountain gravity energy storage combined power generation system, which combines photovoltaic power stations with gravity energy storage to form a combined power generation system, and solves the problem of insufficient power supply to mountain power grids and users in mountainous areas by setting scheduling strategies and planning methods.

A first aspect of the present invention provides a scheduling method based on a photovoltaic-mountain gravity energy storage combined power generation system, wherein the photovoltaic-mountain gravity energy storage combined power generation system comprises a photovoltaic power station and a mountain gravity energy storage device, and the scheduling method comprises:

The unbalanced power ΔP(t) calculated from the output and load data of the photovoltaic power station at time t is:

ΔP(t)= _Ppv (t) _-Pload (t);

Among them, P _pv (t) is the output of the photovoltaic power station at time t, and P _load (t) is the load demand at time t;

When the unbalanced power ΔP(t)>0, the mountain gravity energy storage device works in the energy storage mode for charging. When the energy storage of the mountain gravity energy storage device reaches the capacity limit, the surplus power is sold to the main grid through the PCC point according to the following formula;

P _sell (t)=ΔP (t)-P _s (t);

When the unbalanced power ΔP(t) is less than 0, the output of the photovoltaic power station is insufficient, and the mountain gravity energy storage device works in the energy release mode to discharge. After reaching the discharge limit, the shortfall is purchased from the main grid through the PCC point according to the following formula;

P _buy (t)=|ΔP(t)|-P _g (t);

P _sell (t) and P _buy (t) are the purchased power and sold power of the PCC point at time t, respectively. P _s (t) and P _g (t) are the rated charging power and rated generating power of the mountain gravity energy storage device at time t, respectively.

The second aspect of the present invention provides a grid partition configuration method based on a photovoltaic-mountain gravity energy storage combined power generation system, comprising the following steps:

Establish objective functions and constraints based on relevant data of the photovoltaic-mountain gravity energy storage combined power generation system, and establish a configuration optimization model based on the table functions and constraints; the objective function includes the daily investment and operation cost function of the photovoltaic-mountain gravity energy storage combined power generation system and the reliability function of the photovoltaic-mountain gravity energy storage combined power generation system in the region;

The configuration optimization model is solved by genetic algorithm to obtain the optimal configuration solution.

Furthermore, the daily investment and operation cost function of the photovoltaic-mountain gravity energy storage combined power generation system is:

minF _C (x _i )=(f ₁ +f ₂ +f ₃ )+(f ₄ +f ₅ -f ₆ );

其中，N_pv为光伏数量；h为储能高度；m为重力储能物块质量；n_m为物块数量；n_r为轨道数量；n_z为所规划电网的分区断点；

P_s ^N重力储能额定发电功率、额定充电功率；

为储能系统容量；

指PCC点的购电功率上限、售电功率上限；Among them, _xi represents the variable to be optimized, that is,

Among them, N _pv is the number of photovoltaics; h is the energy storage height; m is the mass of the gravity energy storage block; n _m is the number of blocks; n _r is the number of tracks; n _z is the partition breakpoint of the planned power grid;

P _s ^N gravity energy storage rated power generation and rated charging power;

is the capacity of the energy storage system;

Refers to the upper limit of power purchase and power sale at the PCC point;

_f1 , _f2 , and _f3 are the initial installation cost, operation and maintenance cost, and replacement cost of the photovoltaic-mountain gravity energy storage combined power generation system, respectively; _f4 , _f5 , and _f6 are the energy interaction cost, energy storage power control cost, and new energy subsidy income, respectively.

Furthermore, the initial installation cost, operation and maintenance cost, and replacement cost of the photovoltaic-mountain gravity energy storage combined power generation system are:

z(r,l)=r(1+r) ^l /((1+r) ^l -1);

Where, z is the cost recovery function, r is the discount rate, l is the equipment life; z _rep is the capital debt repayment coefficient, l _rep is the equipment replacement period; C _GBESS is the installation cost of gravity energy storage equipment; C _pv is the installation cost of photovoltaic equipment, C _rb and C _rpv are the installation costs of energy storage and photovoltaic equipment, and C _gr and C _sr are the replacement costs of generators and motors.

Furthermore, the energy interaction cost, energy storage power control cost and new energy subsidy income are respectively:

Where, C _buy (t) and C _sell (t) are the electricity purchase and sales prices at time t; P _buy (t) and P _sell (t) are the electricity purchase and sales power at time t; P _g (t) and P _s (t) are the discharge power and charging power of the energy storage system at time t, respectively; γ is the power control coefficient;

P _pv (t) is the actual output of the photovoltaic power station at time t, which is:

P _pv (t)=P′ _pv (t)+ε _pv (t);

P′ _pv (t) is the predicted output of the photovoltaic power station at time t, ε _pv (t) is the standard deviation of the output error of the photovoltaic power station at time t;

Furthermore, the reliability function of the photovoltaic-mountain gravity energy storage combined power generation system in the area is:

Where E _self,i is the self-power supply of the i-th grid zone, and E _total,i is the self-load demand of the i-th grid zone.

Furthermore, the constraints include power balance constraints, power output and interactive power constraints, and capacity configuration constraints;

The power balance constraint condition is:

N _pv P _pv (t) + P _g (t) + P _buy (t) = P _load (t) + P _sell (t) + P _s (t);

Among them, P _load (t) is the actual load demand of the photovoltaic power station at time t, which is:

P _load (t)=P′ _load (t)+ε _load (t);

Where σ _load (t) is the standard deviation of load demand error, which is:

σ _load (t)=0.04×P _load (t);

The power output and interaction power constraints are:

The capacity configuration constraints are:

h _min ≤h ≤h _max ;

θ _min ≤θ ≤θ _max ;

N _pv ,N _wt ,n _m ,n _rail ,n _z ∈N;

Where N is a non-negative integer set; R is a real number set; h _max is the maximum height of the mountain gravity energy storage installation; θ _max is the maximum inclination angle.

Compared with the prior art, the present invention has the following beneficial effects:

1. The present invention combines a photovoltaic power station and a gravity energy storage device set up in a mountainous area, utilizes the natural advantages of the mountainous terrain to build a gravity energy storage device, combines the working principle of gravity energy storage with the geographical characteristics of photovoltaic power generation in mountainous areas, solves the problems of insufficient power supply in mountainous areas and excessively high costs for laying energy storage equipment and lines, improves the electricity quality of users in mountainous areas, and can participate in the dispatching of superior power grids.

2. The dispatching method of the present invention is based on the advantages and disadvantages of photovoltaic power stations. Combining the gravity energy storage device can not only improve the utilization efficiency of photovoltaic power stations, but also solve the problem that photovoltaic power stations cannot meet the peak electricity demand in mountainous areas at night.

3. The present invention is aimed at the optimization configuration method of the photovoltaic-mountainous gravity energy storage power generation system, which takes into account the uncertain factors related to the photovoltaic power station and the communication cost of the global control. Under the premise of ensuring the relatively highest utilization rate of photovoltaic and gravity energy storage equipment in the partition, gravity energy storage participates in the grid dispatching, takes the economic goal and the reliability goal of the grid partition as the objective function, sets relevant constraints, and builds a configuration optimization model. By solving the configuration optimization model, the optimal configuration scheme is obtained, which can make full use of the photovoltaic resources and energy storage equipment of the grid and reduce the control cost.

The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of a photovoltaic-mountain gravity energy storage combined power generation system according to a specific embodiment of the present invention;

FIG2 is a control principle diagram of a mountain gravity energy storage device according to a specific embodiment of the present invention;

FIG3 is a flow chart of solving a configuration optimization model using a genetic algorithm in a specific embodiment of the present invention.

DETAILED DESCRIPTION

The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

It should be noted that the illustrations provided in the following embodiments are only used to schematically illustrate the basic concept of the present invention, and thus the illustrations only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

While some exemplary embodiments of the present invention have been described for the purpose of illustration, it should be understood that the present invention may be implemented in other ways not specifically shown in the drawings.

In a specific embodiment, a scheduling method based on a photovoltaic-mountain gravity energy storage combined power generation system is provided, wherein the photovoltaic-mountain gravity energy storage combined power generation system includes a photovoltaic power station and a mountain gravity energy storage device, as shown in FIG1 . The basic principle of the photovoltaic-mountain gravity energy storage device in this embodiment is: relying on the altitude difference of the mountain to obtain the change of gravitational potential energy, and converting the mechanical energy generated during the transportation of heavy blocks into electrical energy through a generator and an electric motor. The main structure of the present invention is shown in FIG1 , and includes six parts: a high-altitude energy storage device, a low-altitude energy storage device, an operating track, a mountain photovoltaic power station, and upper-level power grids and mountain power grid users.

As shown in Figure 2, it is the energy conversion principle diagram of the photovoltaic-mountain gravity energy storage system. The insufficient power supply capacity of the power grid to users in mountainous areas has always been a common problem. Photovoltaic power generation in mountainous areas is intermittent. When the photovoltaic output is large during the day, its power generation power is greater than the power load power of users in the area. At this time, the device enters the energy storage mode. When the energy storage mode is running, the photovoltaic power station provides electricity to drive the high-altitude energy storage device to drag the motor, and the standard weight block located in the low-altitude energy storage device is lifted uniformly along the track. The time used is adjusted by controlling the running speed of the fixed motor and the transmission system to convert the electrical energy generated by the photovoltaic device into high-quality potential mechanical energy. When the photovoltaic power generation is not working at night, there is a power gap in the area, and the device enters the power generation mode. When the power generation mode is running, the weight block is lowered from the high-altitude energy storage platform, and mechanical energy is generated by gravity work during the uniform descent process, which drives the generator located on the high-altitude platform to convert the mechanical energy back to electrical energy to meet the power demand of users in the area. The photovoltaic-gravity energy storage combined power generation system of the present invention can have a flexible power supply range of 5 minutes to 6 hours. The capacity of the energy storage device is determined by the number and quality of objects, the height of the device, and the slope of the mountain. The track construction plan can be formulated according to the specific topography of the mountain. The photovoltaic-mountain gravity energy storage combined power generation system is adapted to local conditions in mountain photovoltaic power generation areas, obtains changes in gravitational potential energy through altitude differences, and uses generators and motors to convert the mechanical energy generated during the transportation of heavy blocks into electrical energy. The energy storage device can provide electricity for users in the area at night, and can also participate in grid dispatching. Compared with the combined use of traditional energy storage devices and photovoltaics, it reduces the cost of laying lines and can also effectively improve the quality of electricity for users in mountainous areas.

Based on the above principles, the scheduling method of the combined power generation system based on photovoltaic-mountain gravity energy storage in this embodiment includes:

In order to improve the utilization rate of photovoltaic power, wind power and photovoltaic power generation are given priority. The unbalanced power ΔP(t) at time t is calculated based on the photovoltaic output and load data of the dispatching center:

ΔP(t)= _Ppv (t) _-Pload (t);

Among them, P _pv (t) is the output of the photovoltaic power station at time t, and P _load (t) is the load demand at time t;

When the unbalanced power ΔP(t)>0, the mountain gravity energy storage device works in the energy storage mode for charging. When the energy storage of the mountain gravity energy storage device reaches the capacity limit, the surplus power is sold to the main grid through the PCC point according to the following formula;

P _sell (t)=ΔP (t)-P _s (t);

When the unbalanced power ΔP(t) is less than 0, the output of the photovoltaic power station is insufficient, and the mountain gravity energy storage device works in the energy release mode to discharge. After reaching the discharge limit, the shortfall is purchased from the main grid through the PCC point according to the following formula;

P _buy (t)=|ΔP(t)|-P _g (t);

P _sell (t) and P _buy (t) are the purchased power and sold power of the PCC point at time t, respectively. P _s (t) and P _g (t) are the rated charging power and rated generating power of the mountain gravity energy storage device at time t, respectively.

Regardless of the energy storage mode or power generation mode, the energy storage device can participate in system scheduling based on the operation of the superior power grid while storing excess local photovoltaic power generation and meeting the electricity needs of users at night.

As the penetration rate of photovoltaic power generation gradually increases, the grid structure becomes increasingly complex, and the requirements for power dispatch are getting higher and higher. In view of the complexity of photovoltaic access to the grid in the future and the high cost of current energy storage technology, combined with the advantages of grid zoning energy storage dispatch, this embodiment establishes a photovoltaic-mountain gravity energy storage combined structure based on the terrain characteristics of some photovoltaic power generation, considers the influencing factors of seasonal weather changes in photovoltaic output scenarios, and provides a grid zoning configuration method based on a photovoltaic-mountain gravity energy storage combined power generation system, including the following steps:

S1. Establish objective functions and constraints based on relevant data of the photovoltaic-mountain gravity energy storage combined power generation system, and establish a configuration optimization model based on the table functions and constraints; the objective function includes the daily investment and operation cost function of the photovoltaic-mountain gravity energy storage combined power generation system and the reliability function of the photovoltaic-mountain gravity energy storage combined power generation system in the region;

In this embodiment, the economic goal is taken as the objective function, and the economic optimization goal mainly considers two aspects: investment and operation. The daily investment and operation minimum cost function minF _C ( _xi ) of the photovoltaic-mountain gravity energy storage combined power generation system includes two parts: investment and operation cost, which is:

minF _C (x _i )=(f ₁ +f ₂ +f ₃ )+(f ₄ +f ₅ -f ₆ );

其中，N_pv为光伏数量；h为储能高度；m为重力储能物块质量；n_m为物块数量；n_r为轨道数量；n_z为所规划电网的分区断点；

P_s ^N重力储能额定发电功率、额定充电功率；

为储能系统容量；

指PCC点的购电功率上限、售电功率上限，N代表集合，及重力储能装置有N种型号，对应功率不同。Among them, _f1 , _f2 , and _f3 are the initial installation cost, operation and maintenance cost, and replacement cost of the photovoltaic-mountain gravity energy storage combined power generation system; _f4 , _f5 , and _f6 are the energy interaction cost, energy storage power control cost, and new energy subsidy income; _xi represents the variable to be optimized, that is,

Among them, N _pv is the number of photovoltaics; h is the energy storage height; m is the mass of the gravity energy storage block; n _m is the number of blocks; n _r is the number of tracks; n _z is the partition breakpoint of the planned power grid;

P _s ^N gravity energy storage rated power generation and rated charging power;

is the capacity of the energy storage system;

It refers to the upper limit of the power purchase and sales of the PCC point. N represents the set, and there are N types of gravity energy storage devices with different corresponding powers.

The initial installation cost, operation and maintenance cost, and replacement cost of the photovoltaic-mountain gravity energy storage combined power generation system are:

z(r,l)=r(1+r) ^l /((1+r) ^l -1);

Where, z is the cost recovery function, r is the discount rate, l is the equipment life; z _rep is the capital debt repayment coefficient, l _rep is the equipment replacement period; C _GBESS is the installation cost of gravity energy storage equipment; C _pv is the installation cost of photovoltaic equipment, C _rb and C _rpv are the installation costs of energy storage and photovoltaic equipment, and C _gr and C _sr are the replacement costs of generators and motors.

The energy interaction cost, energy storage power control cost and new energy subsidy income are:

In the formula, C _buy (t) and C _sell (t) are the electricity purchase and sales prices at time t; P _buy (t) and P _sell (t) are the electricity purchase and sales power at time t; P _g (t) and P _s (t) are the discharge power and charging power of the energy storage system at time t respectively; γ is the power control coefficient; λ is the new energy subsidy income ratio coefficient, and the new energy subsidy income needs to be calculated in proportion to the new energy power generation.

There are many uncertain factors in the operation of the power grid. One of the uncertain factors in this embodiment is the output prediction error of the photovoltaic power station. The actual photovoltaic output P _pv (t) can be composed of the predicted output and the error, which is:

P _pv (t)=P′ _pv (t)+ε _pv (t);

P′ _pv (t) is the predicted output of the photovoltaic power station at time t, ε _pv (t) is the standard deviation of the output error of the photovoltaic power station at time t;

The partition configuration strategy of this embodiment is based on the principle of increasing the utilization rate of new energy in the area as much as possible with the cooperation of energy storage devices, and establishes a reliability function to optimize the best partition breakpoint selection.

The self-balancing rate in the area refers to the adaptation relationship between the power supplied by the area itself and the load demand in the area. The change of this value reflects the degree of dependence of the microgrid on the upper main grid during operation. The higher the value, the less dependence and the stronger the independent operation ability. It proves that the partition scheme of the power grid is better. Therefore, the reliability function of the photovoltaic-mountain gravity energy storage combined power generation system in the area described in this embodiment is the self-balancing rate, which is:

Where E _self,i is the self-power supply of the i-th grid zone, and E _total,i is the self-load demand of the i-th grid zone.

The constraints in this embodiment include power balance constraints and capacity configuration constraints;

The power balance constraint condition is:

N _pv P _pv (t) + P _g (t) + P _buy (t) = P _load (t) + P _sell (t) + P _s (t);

Among them, P _load (t) is the actual load demand of the photovoltaic power station at time t, which is:

P _load (t)=P′ _load (t)+ε _load (t);

Where σ _load (t) is the standard deviation of load demand error, which is:

σ _load (t)=0.04×P _load (t);

The power output and interaction power constraints are:

The capacity configuration constraints are:

h _min ≤h ≤h _max ;

θ _min ≤θ ≤θ _max ;

N _pv ,N _wt ,n _m ,n _rail ,n _z ∈N;

Where N is a non-negative integer set; R is a real number set; h _max is the maximum height of the mountain gravity energy storage installation; θ _max is the maximum inclination angle.

S2. Solve the configuration optimization model through genetic algorithm to obtain the optimal configuration solution.

The genetic algorithm used in this embodiment is shown in FIG3 . The process of solving the configuration optimization model by the genetic algorithm includes:

S21, initializing the optimization variable x _i , the optimization variable x _i is

Set the maximum number of iterations T, the maximum number of partitions, the mutation rate, and the crossover rate;

S22, taking the objective function in the configuration optimization model as the fitness function, i.e., the daily investment and operation cost and the self-balancing rate within the zone;

S23, after performing selection, crossover and mutation operations on each individual in the initial population, a new generation of population is generated;

S24, calculate the fitness of the new generation population;

S25, determine whether the maximum number of iterations T is reached, if so, execute step S26, if not, execute step S23;

S26, output all optimization results corresponding to the number of breakpoints between partitions;

S27, determine whether the preset maximum number of partitions is reached, if yes, output all parameter configuration schemes to obtain the optimal configuration scheme, if no, execute step S28;

S28, repeat the step of initializing the optimized variables in step S21.

The genetic algorithm used in the method for solving the configuration optimization model in this embodiment can be a basic genetic algorithm, or other model solving algorithms in the prior art can be used for solving. Since this part is not the focus of this application, it will not be described here.

The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims (7)

1. A scheduling method based on a photovoltaic-mountain gravity energy storage combined power generation system is characterized in that the photovoltaic-mountain gravity energy storage combined power generation system comprises a photovoltaic power station and a mountain gravity energy storage device, and the scheduling method comprises the following steps:

when the output and load data of the photovoltaic power station at the moment t are calculated, the unbalanced electric quantity delta P (t) is as follows:

ΔP(t)＝P _pv (t)-P _load (t)；

wherein, P _pv (t) is the photovoltaic power station output at time t, P _load (t) load demand at time t;

when the unbalanced electric quantity delta P (t) > 0, the mountain gravity energy storage device works in an energy storage mode to charge, and when the energy storage of the mountain gravity energy storage device reaches a capacity limit value, surplus electric quantity is sold to the main network through a PCC (point-of-charge controller) point according to the following formula;

P _sell (t)＝ΔP(t)-P _s (t)；

when the unbalanced electric quantity delta P (t) is less than 0, the output of the photovoltaic power station is insufficient, the mountain gravity energy storage device discharges in an energy release mode, and after the discharge electrode limit is reached, the shortage electric quantity is purchased to the main network through a PCC (point-of-charge controller) point according to the following formula;

P _buy (t)＝|ΔP(t)|-P _g (t)；

P _sell (t) and P _buy (t) power purchase and power sale at the moment of PCC point t, P _s (t)、P _g And (t) respectively representing rated charging power and rated generating power of the mountain gravity energy storage device at the moment t.

2. A power grid partition configuration method based on a photovoltaic-mountain gravity energy storage combined power generation system is characterized by comprising the following steps:

establishing a target function and a constraint condition according to relevant data of the photovoltaic-mountain gravity energy storage combined power generation system, and establishing a configuration optimization model according to the table function and the constraint condition; the target function comprises a daily investment operation cost function of the photovoltaic-mountain gravity energy storage combined power generation system and a reliability function of the photovoltaic-mountain gravity energy storage combined power generation system in the region;

and solving the configuration optimization model through a genetic algorithm to obtain an optimal configuration scheme.

3. The power grid partition configuration method based on the photovoltaic-mountain gravity energy storage combined power generation system according to claim 2, wherein a daily investment operation cost function of the photovoltaic-mountain gravity energy storage combined power generation system is as follows:

minF _C (x _i )＝(f ₁ +f ₂ +f ₃ )+(f ₄ +f ₅ -f ₆ )；

wherein, x in the formula _i Representing variables to be optimized, i.e.

Wherein N is _pv Is the photovoltaic number; h is the energy storage height; m is the mass of the gravity energy storage object block; n is a radical of an alkyl radical _m The number of the material blocks; n is a radical of an alkyl radical _r The number of tracks; n is _z Partitioning breakpoints for the planned power grid;

P _s ^N The gravity energy storage rated power generation power and the rated charging power;

Is the energy storage system capacity;

the upper limit of electricity purchasing power and the upper limit of electricity selling power of the PCC points are indicated;

f ₁ 、f ₂ 、f ₃ the initial installation cost, the operation maintenance cost and the replacement cost of the photovoltaic-mountain gravity energy storage combined power generation system are respectively set; f. of ₄ 、f ₅ 、f ₆ Respectively subsidizing the benefits for the energy interaction cost, the energy storage electric quantity control cost and the new energy.

4. The power grid partition configuration method based on the photovoltaic-mountain gravity energy storage combined power generation system as claimed in claim 3, wherein the initial installation cost, the operation maintenance cost and the replacement cost of the photovoltaic-mountain gravity energy storage combined power generation system are respectively:

z(r,l)＝r(1+r) ^l /((1+r) ^l -1)；

wherein z is a cost recovery function, r is a discount rate, and l is the service life of equipment; z is a radical of formula _rep As a capital debt coefficient, l _rep The equipment remanufacturing age limit; c _GBESS Is the installation cost of the gravity energy storage equipment; c _pv Installation cost of photovoltaic apparatus, C _rb 、C _rpv Installation cost of energy storage and photovoltaic equipment, C _gr 、C _sr The cost of the generator and the motor is replaced.

5. The power grid partition configuration method based on the photovoltaic-mountain gravity energy storage combined power generation system as claimed in claim 3, wherein the energy interaction cost, the energy storage electric quantity control cost and the new energy subsidy profit are respectively as follows:

in the formula, C _buy (t)、C _sell (t) the price of electricity purchased and sold at the moment t; p _buy (t)、P _sell (t) purchasing and selling power at time t; p _g (t) and P _s (t) respectively obtaining discharge power and charging power of the energy storage system at the moment t; gamma is an electric quantity control coefficient;

P _pv (t) is the actual output of the photovoltaic power station at the moment t, and comprises the following steps:

P _pv (t)＝P′ _pv (t)+ε _pv (t)；

P′ _pv (t) predicted output at time t of photovoltaic power station, ε _pv (t) is the standard deviation of the output error of the photovoltaic power station at the moment t;

6. the power grid partition configuration method based on the photovoltaic-mountain gravity energy storage combined power generation system according to claim 3, wherein the reliability function of the photovoltaic-mountain gravity energy storage combined power generation system in the region is as follows:

in the formula, E _self,i Power supply per se in the i-th subarea of the grid, E _total,i The load demand of the power grid in the partition I is self-load demand.

7. The power grid partition configuration method based on the photovoltaic-mountain gravity energy storage combined power generation system, according to claim 2, wherein the constraint conditions include a power balance constraint condition, a power output and interaction power constraint condition, and a capacity configuration constraint condition;

the power balance constraint conditions are as follows:

N _pv P _pv (t)+P _g (t)+P _buy (t)＝P _load (t)+P _selll (t)+P _s (t)；

wherein, P _load (t) is the actual load demand of the photovoltaic power station at the moment t, and comprises the following steps:

P _load (t)＝P′ _load (t)+ε _load (t)；

wherein σ _load (t) is the standard deviation of the load demand error, which is:

σ _load (t)＝0.04×P _load (t)；

the constraint conditions of the power output and the interactive power are as follows:

the capacity configuration constraint conditions are as follows:

h _min ≤h≤h _max ；

θ _min ≤θ≤θ _max ；

N _pv ,N _wt ,n _m ,n _rail ,n _z ∈N；

in the formula, N is a non-negative integer set; r is a real number set; h is _max The maximum height for the gravity energy storage installation of the mountain; theta _max Is the maximum tilt angle.

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