CN116805792B - Method and system for determining thermal power-energy storage regulation demand in high-proportion new energy systems - Google Patents

Abstract

The invention discloses a thermal power-energy storage regulation demand judging method in a high-proportion new energy system, which comprises the steps of obtaining data information of a target power system; constructing a power balance expression; judging the electric quantity balance state of the target electric power system under a typical day; constructing a power demand constraint condition of the target power system when the peak load is met; constructing a supporting power supply capacity benefit index and a supporting power supply capacity replacement benefit index; and finishing judgment of thermal power-energy storage regulation requirements in the high-proportion new energy system. The invention also discloses a system for realizing the thermal power-energy storage regulation demand judging method in the high-proportion new energy system. The invention not only realizes the judgment of the thermal power-energy storage regulation requirement in a high-proportion new energy system through the innovative judgment process and calculation index, but also has high reliability, good accuracy and objectivity and science based on objective power system data and calculated indexes.

Description

Method and system for determining thermal power-energy storage regulation demand in high-proportion new energy systems

Technical Field

The present invention belongs to the field of electrical automation, and in particular relates to a method and system for determining thermal power-energy storage regulation demand in a high-proportion new energy system.

Background technique

With the development of economy and technology and the improvement of people's living standards, electricity has become an indispensable secondary energy source in people's production and life, bringing endless convenience to people's production and life. Therefore, ensuring the stable and reliable supply of electricity has become one of the most important tasks of the power system.

At present, with the integration of new energy power generation systems into the power grid, the penetration rate of new energy power generation is constantly increasing; however, the intermittent, volatile and random characteristics of new energy power generation will cause the net load of the power grid to fluctuate, which brings great challenges to the safe and stable operation of the power system.

With the construction of new power systems and the increase in the proportion of new energy sources, the basic supporting power sources of the power system may have insufficient capacity, which will lead to insufficient cross-time and cross-season allocation capabilities. The continuous peak operation pressure of the power system is high and insufficient to meet the needs of power balance, thus affecting the safe and stable operation of the power system. At present, traditional thermal power units are undergoing corresponding performance improvement and flexibility transformation, and the application of energy storage technology has also brought practical solutions to the "peak shaving and valley filling" of thermal power units. However, excessive configuration of energy storage will not only fail to effectively reduce the installed capacity of supporting power sources such as thermal power units, but also reduce the economy and efficiency of system operation.

Therefore, the existing power system often uses thermal power-energy storage to adjust the power system load. However, the current method for determining the thermal power-energy storage adjustment method of the power system still adopts a simple human subjective judgment scheme; obviously, the human subjective judgment scheme not only has poor reliability and consistency, but also is highly subjective and lacks corresponding judgment basis.

Summary of the invention

One of the purposes of the present invention is to provide a method for determining thermal power-energy storage regulation demand in a high-proportion new energy system with high reliability, good accuracy, and objectivity and science.

A second object of the present invention is to provide a system for realizing the method for determining the thermal power-energy storage regulation demand in the high-proportion new energy system.

The method for determining the thermal power-energy storage regulation demand in the high-proportion new energy system provided by the present invention comprises the following steps:

S1. Obtain data information of the target power system;

S2. Construct a power balance expression based on the data information obtained in step S1;

S3. Determine the power balance state of the target power system on a typical day;

S4. Construct the power demand constraint conditions of the target power system when meeting the peak load;

S5. Based on the obtained data results, construct supporting power capacity benefit indicators and supporting power capacity substitution benefit indicators;

S6. Based on the indicators obtained in step S5, the thermal power-energy storage regulation demand in the high-proportion new energy system is determined.

The step S2 of constructing a power balance expression according to the data information obtained in step S1 specifically includes the following steps:

The following formula is used as the power balance expression:

P _thermal (t)＝ _PL (t) _-PESS (t)

Where P _thermal (t) is the output of the thermal power unit; P _ESS (t) is the energy storage power. When the energy storage device is charging, P _ESS (t) is a negative value, and when the energy storage device is discharging, P _ESS (t) is a positive value; _PL (t) is the required load of the target power system, and the expression is _PL (t) = P _load (t) - (P _hydro (t) + P _RES (t) + P _DC (t) + P _region (t) + P _gas (t)), P _load (t) is the system load power, P _hydro (t) is the output of the hydropower unit, P _RES (t) is the output of wind power and photovoltaic power, P _DC (t) is the DC power, when DC power is sent into the power system, P _DC (t) is positive, when DC power is sent out of the power system, P _DC (t) is negative, P _region (t) is the power of the AC interconnection line between regional power grids, and P _gas (t) is the gas power. When gas power is sent into the power system, P _gas (t) is positive, when gas power is sent out of the power system, P _gas (t) is negative.

The step S3 of determining the power balance state of the target power system on a typical day specifically includes the following steps:

The following rules are used to determine the power balance state of the target power system on a typical day:

Where P _thermal.max is the maximum output of the thermal power unit in the system; Δt is the set time period; N is the total number of time periods; δ is the energy storage efficiency; (P _thermal.max -P _L (t)) _{> 0} means that the value of P _thermal.max -P _L (t) is greater than 0; (P _thermal.max -P _L (t)) _{< 0} means that the value of P _thermal.max -P _L (t) is less than 0;

If the target power system meets the above rules, it means that under the existing thermal power installed capacity, the target power system can meet the power balance on a typical day through energy storage configuration;

If the target power system does not meet the above rules, it means that the target power system needs to increase the installed capacity of thermal power units in order to meet the power balance of the target power system on a typical day.

The step S4 of constructing the power demand constraint condition of the target power system when meeting the peak load specifically includes the following steps:

The following formula is used to construct the power demand constraint during peak load:

P _L (t)-P _thermal.max ≤P _ESS (t)≤0

P _ESS (t) ≥ max (P _L (t) - P _{thermal, max} ) > 0

-P _ESS,max ≤P _ESS (t)≤P _ESS,max

P _thermal (t)≥βP _thermal,max

W _peak ≤t _t ·P _ESS,max

Where β is the minimum output ratio of the thermal power unit; P _ESS,max is the maximum value of the energy storage charging or discharging power; W _peak is the power shortage during the peak load period; t _t is the charging or discharging time of the energy storage at full power.

According to the obtained data results, the step S5 constructs the supporting power capacity benefit index and the supporting power capacity substitution benefit index, which specifically includes the following steps:

The supporting power capacity benefit index η is calculated using the following formula:

Where ΔP _thermal is the increased capacity of thermal power installed capacity calculated by theoretical analysis; ΔP′ _thermal is the actual increased capacity of thermal power installed capacity;

If the target power system still cannot meet the power balance constraint requirements after increasing the capacity of thermal power units, the power balance problem of the system under typical load days can be solved by configuring energy storage devices;

After adding the energy storage device, the supporting power capacity substitution benefit index α is calculated using the following formula:

Where P _ESS,in,max is the maximum charging power of the energy storage; P _ESS,out,max is the maximum discharging power of the energy storage; and P _ESS,max is the configured capacity of the energy storage.

Step S6, according to the index obtained in step S5, completes the determination of the thermal power-energy storage regulation demand in the high-proportion new energy system, and specifically includes the following steps:

The supporting power source substitution benefit rate index λ is calculated using the following formula:

Where α is the supporting power capacity replacement benefit index; η is the supporting power capacity benefit index;

According to the calculated supporting power source substitution benefit rate index λ, the judgment is made:

The value of λ is equal to 1, indicating that the capacity benefits of energy storage and thermal power units are the same;

The closer the value of λ is to 1, the higher the supporting power source replacement efficiency of energy storage is;

The further away the value of λ is from 1, the lower the supporting power source replacement efficiency of energy storage is.

The present invention also provides a system for realizing the method for determining the thermal power-storage regulation demand in the high-proportion new energy system, comprising a data acquisition module, a balance expression module, a balance determination module, a constraint construction module, an index construction module and a determination module; the data acquisition module, the balance expression module, the balance determination module, the constraint construction module, the index construction module and the determination module are connected in series in sequence; the data acquisition module is used to acquire data information of the target power system, and upload the data to the balance expression module; the balance expression module is used to construct a power balance expression according to the received data, and upload the data to the balance determination module; the balance determination module is used to determine the power balance state of the target power system on a typical day according to the received data, and upload the data to the constraint construction module; the constraint construction module is used to construct the power demand constraint conditions of the target power system when meeting the peak load according to the received data, and upload the data to the index construction module; the index construction module is used to construct a supporting power capacity benefit indicator and a supporting power capacity substitution benefit indicator according to the received data, and upload the data to the determination module; the determination module is used to complete the determination of the thermal power-storage regulation demand in the high-proportion new energy system according to the received data.

The method and system for determining the thermal power-storage regulation demand in a high-proportion new energy system provided by the present invention not only realizes the determination of the thermal power-storage regulation demand in a high-proportion new energy system through an innovative determination process and calculation indicators, but also the present invention is based on objective power system data and calculated indicators, and is highly reliable, accurate, objective and scientific.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of a method flow chart of the method of the present invention.

FIG2 is a schematic diagram of a full-element curve of the power system of a provincial power grid on a typical high-load day in 2015 according to an embodiment of the method of the present invention.

FIG3 is a schematic diagram of a full-factor curve of a power system after increasing the installed capacity of thermal power plants according to an embodiment of the method of the present invention.

4 is a schematic diagram of a power generation load curve required by the system after deducting the output of hydropower, new energy, AC/DC interconnection lines, and gas-fired power generation according to an embodiment of the method of the present invention.

FIG. 5 is a schematic diagram of the functional modules of the system of the present invention.

Detailed ways

FIG1 is a schematic diagram of the method flow of the method of the present invention: The method for determining the thermal power-energy storage regulation demand in the high-proportion new energy system disclosed in the present invention comprises the following steps:

S1. Obtain data information of the target power system;

S2. Construct a power balance expression based on the data information obtained in step S1; specifically comprising the following steps:

With the large-scale development of new energy, new energy will be an important provider of electricity and have a considerable degree of "grid building" capability, while thermal power, as a conventional power source, will gradually shift to regulation and support. The power balance mode will shift from "source follows load" power generation/consumption balance to energy storage and multi-energy conversion to participate in buffering in a larger space and a larger time scale. Therefore, energy storage, as a key technology to solve the problem of large-scale access and absorption of renewable energy, needs to participate in power balance analysis and grid regulation capacity analysis. For this purpose, it is necessary to comprehensively consider the impact of thermal power-energy storage configuration on system power balance.

The following formula is used as the power balance expression:

P _thermal (t)＝ _PL (t) _-PESS (t)

Wherein, P _thermal (t) is the output of the thermal power unit; P _ESS (t) is the energy storage power. When the energy storage device is charging, P _ESS (t) is a negative value, and when the energy storage device is discharging, P _ESS (t) is a positive value; _PL (t) is the load required by the target power system, and the expression is _PL (t) = P _load (t) - (P _hydro (t) + P _RES (t) + P _DC (t) + P _region (t) + P _gas (t)), P _load (t) is the system load power, P _hydro (t) is the output of the hydropower unit, P _RES (t) is the output of wind power and photovoltaic power, P _DC (t) is the DC power, when the DC power is sent into the power system, P _DC (t) is positive, when the DC power is sent out of the power system, P _DC (t) is negative, P _region (t) is the power of the AC interconnection line between regional power grids, P _gas (t) is the gas power, when the gas power is sent into the power system, P _gas (t) is positive, when the gas power is sent out of the power system, P _gas (t) is negative;

S3. Determine the power balance state of the target power system on a typical day; specifically, the steps include:

In order to meet the peak load power support, energy storage must not only meet the power demand at the peak load moment, but also have sufficient power (power) to be charged, that is, a power supply of a certain scale is required to provide the required power (power); the chargeable amount is greater than or equal to the power demand of the system at the peak load moment, and the energy storage efficiency needs to be considered during the calculation; the following rules are used to determine the power balance state of the target power system on a typical day:

Where P _thermal.max is the maximum output of the thermal power unit in the system; Δt is the set time period; N is the total number of time periods; δ is the energy storage efficiency, which is usually between 0.7 and 0.9; (P _thermal.max -P _L (t)) _{> 0} means that the value of P _thermal.max -P _L (t) is greater than 0; (P _thermal.max -P _L (t)) _{< 0} means that the value of P _thermal.max -P _L (t) is less than 0;

In specific implementation, Δt is generally taken as 0.25h, so N is taken as 96;

If the target power system meets the above rules, it means that under the existing thermal power installed capacity, the target power system can meet the power balance on a typical day through energy storage configuration;

If the target power system does not meet the above rules, it means that the target power system needs to increase the installed capacity of thermal power units to meet the target power system's power balance on a typical day;

S4. Construct the power demand constraint conditions of the target power system when meeting the peak load; specifically, the steps include:

The following formula is used to construct the power demand constraint during peak load:

P _L (t)-P _thermal.max ≤P _ESS (t)≤0

P _ESS (t) ≥ max (P _L (t) - P _{thermal, max} ) > 0

-P _ESS,max ≤P _ESS (t)≤P _ESS,max

P _thermal (t)≥βP _thermal,max

W _peak ≤t _t ·P _ESS,max

Where β is the minimum output ratio of the thermal power unit; P _ESS,max is the maximum value of the energy storage charging or discharging power; W _peak is the power shortage during the peak load period; t _t is the charging or discharging time of the energy storage at full power, which is generally 2 hours, 4 hours or 6 hours;

Among them, the first constraint condition indicates that the actual charging power of the energy storage is less than or equal to the system surplus power during the load valley period, combined with the energy storage configuration requirements for power supply during the peak load period, thus avoiding the economic problems of the energy storage system caused by excessive configuration of energy storage; the second constraint condition indicates that the actual discharge power of the energy storage must be greater than or equal to the maximum power shortage at the peak load moment, thus meeting the power balance requirements during the peak load period; the third constraint condition represents the power constraint of energy storage charging and discharging;

S5. Based on the obtained data results, construct supporting power capacity benefit indicators and supporting power capacity substitution benefit indicators; specifically including the following steps:

The supporting power capacity benefit index η is calculated using the following formula:

Where ΔP _thermal is the increased capacity of thermal power installed capacity calculated by theoretical analysis; ΔP _t ' _hermal is the actual increased installed capacity of thermal power;

In specific implementation, considering that the capacity of a single unit is usually 600 MW or 1000 MW when new thermal power generation capacity is installed in the current power system, the calculation formula of the supporting power capacity benefit index η can be modified as follows: a is the number of additional 600 MW thermal power units, and b is the number of additional 1000 MW thermal power units;

For the supporting power capacity efficiency index η:

The closer η is to 1, the better the system power balance can be achieved by increasing the capacity of thermal power units without considering the configuration of energy storage, and the better the capacity benefit;

The closer η is to 0, it means that although the capacity of thermal power units is increased to meet the power balance of the system, the capacity efficiency is poor;

If the target power system still cannot meet the power balance constraint requirements after increasing the capacity of thermal power units, the power balance problem of the system under typical load days can be solved by configuring energy storage devices;

After adding the energy storage device, the supporting power capacity substitution benefit index α is calculated using the following formula:

Where P _ESS,in,max is the maximum charging power of the energy storage; P _ESS,out,max is the maximum discharging power of the energy storage; P _ESS,max is the energy storage configuration capacity;

S6. According to the index obtained in step S5, the determination of the thermal power-storage regulation demand in the high-proportion new energy system is completed; specifically, the following steps are included:

The supporting power source substitution benefit rate index λ is calculated using the following formula:

Where α is the supporting power capacity replacement benefit index; η is the supporting power capacity benefit index;

According to the calculated supporting power source substitution benefit rate index λ, the judgment is made:

The value of λ is equal to 1, which means that the capacity benefits of energy storage and thermal power units are the same. From the perspective of safe and stable operation of the system, the power balance of the system can be maintained by increasing the capacity of thermal power units.

The closer the value of λ is to 1, the higher the efficiency of supporting power source substitution of energy storage is. At the same time, the configuration of energy storage is also conducive to improving the new energy consumption capacity;

The further away the value of λ is from 1, the lower the supporting power source replacement efficiency of energy storage is.

The method of the present invention is further described below in conjunction with an embodiment:

Taking the operation of a provincial power grid on a typical high-load day in 2015 as an example, the power balance and required energy storage capacity of the system in 2015 are analyzed. The system curve of the provincial power grid on a typical high-load day in 2015 is shown in Figure 2, with 15-minute points as intervals. The minimum output ratio of the system's thermal power units β = 33%, and the energy storage efficiency δ = 75%.

Under the initial conditions, the maximum output of the thermal power installed capacity is 23000MW. Under this condition, the system can be charged 10179.3MWh, while the discharge power during the peak load period of a typical heavy load day is 28914.5MWh. Therefore, under the existing thermal power installed capacity, the system's power balance cannot be met, and the power balance cannot be met at the same time. It is necessary to increase the thermal power installed capacity to meet the constraint conditions, that is, the power balance constraint under a typical heavy load day.

After calculation, it can be seen that when the installed capacity of 1000MW thermal power plant is increased, the full factor curve of the system is shown in Figure 3. From the curve analysis in the figure, it can be seen that the system can be charged on a typical high-load day for 19929.3MWh, and the required discharge power during the peak load period is 14664.5MWh. Considering the efficiency of energy storage charging and discharging, the discharge power based on the chargeable capacity is 14946.9MWh, which can meet the power balance constraint on a typical high-load day.

The required power generation load curve of the system after deducting the output of hydropower, new energy, AC/DC interconnection lines, and gas-fired power generation is shown in Figure 4.

As shown in Figure 4, the maximum power shortage of the system during the peak load period is 1940.47MW. The minimum load value of the power generation load curve required by the system after deduction is 20869.08MW, which is greater than the minimum output constraint of 8000MW of the thermal power unit at this time.

When energy storage is not considered, the theoretically calculated additional thermal power installed capacity is the maximum power shortage value. According to the existing thermal power unit types, the system needs to add two 1000MW thermal power units to meet the power demand under typical high-load days in 2025. Therefore, it can be calculated that

When considering the configuration of energy storage, according to the maximum power shortage during the peak load period, the initial energy storage capacity is configured to be at least 1940MW, so as to meet the power balance constraint during the peak load period. However, it is also necessary to meet the power balance constraint. Therefore, according to the power shortage during the peak load period, the energy storage configuration capacity after considering the energy storage conversion efficiency δ = 75% is 3320MW;

Then, according to the actual curve analysis, after configuring the energy storage, the maximum charging power during the energy storage charging process is 3130MW, and the maximum discharge power is 1940MW, which can meet the power balance constraint of the system during the peak load period, and the energy storage charging and discharging also meet the power constraint conditions. Therefore, the supporting power supply capacity substitution benefit index α and the supporting power supply substitution benefit rate index λ can be calculated:

It can be judged that the replacement efficiency rate of supporting power supply of energy storage can reach 97%, indicating that energy storage can play a good role in the balance of power and electricity in the system. At the same time, configuring a certain scale of energy storage can also help improve the level of consumption of new energy. Therefore, the method proposed in the present invention reduces the capacity demand of thermal power installed units through energy storage configuration, improves the peak load regulation capacity and cross-time and cross-season regulation capacity of the system, solves the power and electricity imbalance caused by load characteristics and the problem of system power supply guarantee, is conducive to the construction of new power systems and thermal power-new energy-energy storage supporting power supply, and then provides scientific and reasonable analysis methods for system staff, which is of great significance in engineering practice, power grid planning and construction, and energy and power security.

As shown in Figure 5, it is a schematic diagram of the functional modules of the system of the present invention: the system disclosed in the present invention for realizing the method for determining the thermal power-storage regulation demand in the high-proportion new energy system includes a data acquisition module, a balance expression module, a balance determination module, a constraint construction module, an index construction module and a determination module; the data acquisition module, the balance expression module, the balance determination module, the constraint construction module, the index construction module and the determination module are connected in series in sequence; the data acquisition module is used to acquire data information of the target power system and upload the data to the balance expression module; the balance expression module is used to construct a power balance expression according to the received data and upload the data to the balance determination module; the balance determination module is used to determine the power balance state of the target power system on a typical day according to the received data and upload the data to the constraint construction module; the constraint construction module is used to construct the power demand constraint conditions of the target power system when meeting the peak load according to the received data and upload the data to the index construction module; the index construction module is used to construct a supporting power capacity benefit indicator and a supporting power capacity substitution benefit indicator according to the received data and upload the data to the determination module; the determination module is used to complete the determination of the thermal power-storage regulation demand in the high-proportion new energy system according to the received data.

Claims (2)

1. A thermal power-energy storage regulation demand judging method in a high-proportion new energy system comprises the following steps:

S1, acquiring data information of a target power system;

S2, constructing a power balance expression according to the data information acquired in the step S1; the method specifically comprises the following steps:

The following formula is used as the power balance expression:

P_thermal(t)＝P_L(t)-P_ESS(t)

Wherein P _thermal (t) is the output of the thermal power unit; p _ESS (t) is energy storage power, P _ESS (t) is a negative value when the energy storage device is charged, and P _ESS (t) is a positive value when the energy storage device is discharged; p _L (t) is the load required by a target power system, the expression is P_L(t)＝P_load(t)-(P_hydro(t)+P_RES(t)+P_DC(t)+P_region(t)+P_gas(t)),P_load(t), P _hydro (t) is the power of a hydroelectric generating set, P _RES (t) is the power of wind power and photovoltaic, P _DC (t) is direct current power, P _DC (t) is positive when the direct current power is sent into the power system, P _DC (t) is negative when the direct current power is sent out of the power system, P _region (t) is the power of an alternating current connecting line between regional power grids, P _gas (t) is gas electric power, P _gas (t) is positive when the gas electric power is sent into the power system, and P _gas (t) is negative when the gas electric power is sent out of the power system;

S3, judging the electric quantity balance state of the target electric power system under a typical day; the method specifically comprises the following steps:

the following rules are adopted to judge the state of charge balance of a target power system under a typical day:

Wherein P _thermal.max is the maximum output of the thermal power unit of the system; Δt is a set period of time; n is the total number of time periods; delta is energy storage efficiency; (P _thermal.max-P_L(t))_＞0 represents a value greater than 0 in P _thermal.max-P_L (t), and (P _thermal.max-P_L(t))_＜0 represents a value less than 0 in P _thermal.max-P_L (t);

if the target power system meets the rule, the electric quantity balance under the typical day can be met through the energy storage configuration under the condition that the target power system is installed in the existing thermal power installation;

if the target power system does not meet the rule, the target power system is required to increase the installed capacity of the thermal power unit so as to meet the electric quantity balance of the target power system under the typical day;

s4, constructing an electric power demand constraint condition of the target electric power system when the peak load is met; the method specifically comprises the following steps:

the power demand constraint at peak load is constructed using the following equation:

P_L(t)-P_thermal.max≤P_ESS(t)≤0

P_ESS(t)≥max(P_L(t)-P_thermal,max)＞0

-P_ESS,max≤P_ESS(t)≤P_ESS,max

P_thermal(t)≥βP_thermal,max

W_peak≤t_t·P_ESS,max

Wherein beta is the minimum output proportion of the thermal power unit; p _ESS,max is the maximum value of the stored charge or discharge power; w _peak is the electric quantity which is lack in the peak load time; t _t is the charging or discharging time of the stored energy full power;

The first constraint condition indicates that the actual power charging power of the energy storage is smaller than or equal to the surplus power of the system in the load valley period, and the energy storage configuration requirement is met by combining the power supply protection in the peak load period, so that the problem of energy storage system economy caused by excessive configuration of energy storage is avoided; the second constraint condition indicates that the actual discharge power of the energy storage must be greater than or equal to the maximum power shortage at the moment of the peak load, so as to meet the power balance requirement in the peak load period; the third constraint condition represents the power constraint of energy storage charge and discharge;

S5, constructing a supporting power supply capacity benefit index and a supporting power supply capacity replacement benefit index according to the obtained data result; the method specifically comprises the following steps:

the following formula is adopted to calculate the supporting power supply capacity benefit index eta:

wherein DeltaP _thermal is the added capacity of the thermal power installation obtained by theoretical analysis and calculation; Δp _t'_hermal is the actual increased thermal power plant capacity;

if the target power system still cannot meet the requirement of the power balance constraint condition after the capacity of the thermal power unit is increased, the problem of power and electricity balance of the system under a typical load day is solved by configuring an energy storage device;

after the energy storage device is added, the following formula is adopted to calculate the supportive power source capacity substitution benefit index alpha:

Wherein P _ESS,in,max is the maximum charging power of the stored energy; p _ESS,out,max is the energy storage maximum discharge power; p _ESS,max is the energy storage configuration capacity;

S6, finishing judgment of thermal power-energy storage regulation requirements in the high-proportion new energy system according to the indexes obtained in the step S5; the method specifically comprises the following steps:

The supporting power supply replacement benefit rate index lambda is calculated by adopting the following formula:

wherein alpha is a supporting power supply capacity substitution benefit index; η is a supportive power source capacity benefit index;

According to the calculated supported power supply replacement benefit rate index lambda, judging:

The value of lambda is equal to 1, which indicates that the capacity benefit of the energy storage unit and the thermal power unit is the same;

the closer the value of λ is to 1, the higher the backup power substitution efficiency of the stored energy;

the further the value of λ is from 1, the lower the backup power substitution efficiency of the stored energy.

2. A system for realizing the thermal power-energy storage regulation demand judging method in the high-proportion new energy system according to claim 1, which is characterized by comprising a data acquisition module, a balance expression module, a balance judging module, a constraint constructing module, an index constructing module and a judging module; the data acquisition module, the balance expression module, the balance judgment module, the constraint construction module, the index construction module and the judgment module are sequentially connected in series; the data acquisition module is used for acquiring data information of the target power system and uploading the data to the balance expression module; the balance expression module is used for constructing a power balance expression according to the received data and uploading the data to the balance judgment module; the balance judging module is used for judging the electric quantity balance state of the target power system under the typical day according to the received data, and uploading the data to the constraint construction module; the constraint construction module is used for constructing power demand constraint conditions of the target power system when the peak load is met according to the received data, and uploading the data to the index construction module; the index construction module is used for constructing a supporting power supply capacity benefit index and a supporting power supply capacity replacement benefit index according to the received data, and uploading the data to the judging module; the judging module is used for finishing judging the thermal power-energy storage regulation requirement in the high-proportion new energy system according to the received data.