Power system cost optimization method, device, equipment and medium

Abstract

The invention relates to an electric power system cost optimization method and device, equipment and a medium, and the method comprises the steps: constructing a target function according to various operation costs in the operation process of an electric power system; determining various constraint conditions in the operation process of the power system to determine the load power of the operation of the power system at the target moment; according to various constraint conditions, the target function is calculated, the minimum value of the total operation cost of the electric power system in the target period is obtained, the operation state of each power generation main body in the electric power system when the total operation cost is the minimum value is obtained, and each power generation main body comprises a thermal power generating unit, a wind power generating unit and a photovoltaic unit; and according to the operation state of each power generation main body, the operation state of each power generation main body is adjusted in the next period of the target period, so that the operation cost of the whole power system is reduced, and economic operation of the power system is realized.

Description

Technical Field

[0001] The present disclosure relates to the field of power systems, and in particular to a method, device, equipment and medium for optimizing power system costs. Background Art

[0002] With the proposal of the "dual carbon" goals, renewable energy will gradually become the main power source for future power systems. However, wind and solar power generation, which is highly dependent on meteorological and weather conditions, will bring great randomness and uncertainty to the operation of the power system. Therefore, the gradual increase in the proportion of renewable resources will have an important impact on the safe and stable operation of the power system. In recent years, many ways and methods have been proposed to increase the flexibility of the power system to cope with the randomness and uncertainty of renewable energy, such as the flexibility transformation of thermal power, the expansion of power transmission lines, and the addition of multiple types of energy storage, which are all helpful to achieve the flexibility balance of the power system. However, in this process, a lot of costs are added to the power system as a whole.

[0003] As the proportion of new energy access continues to increase, the construction of new power systems with new energy as the main body is accelerating. We should accelerate the process of source-grid-load-storage integration to better serve the new energy system. In the process of building a new power system, while ensuring the stable operation of the system, the economic feasibility of system construction should also be considered to obtain the sustainable and healthy development of the new power system. In order to ensure the sustainable development of the power system, it is necessary to optimize all aspects of the power system operation process. Summary of the invention

[0004] In order to overcome the problems existing in the related art, the present disclosure provides a method, device, equipment and medium for optimizing power system cost.

[0005] According to a first aspect of an embodiment of the present disclosure, there is provided a method for optimizing power system costs, including:

[0006] According to various operating costs in the operation of the power system, an objective function is constructed, wherein the various operating costs include thermal power operation cost, thermal power pollutant emission cost, penalty cost for abandoned new energy and abandoned electricity, thermal power carbon trading cost, energy storage system operation cost and interrupted load compensation cost;

[0007] Determine various constraints during the operation of the power system to determine the load power of the power system at the target time, wherein the various constraints include the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, the discharge power and charging power of the energy storage system at the target time, and standby constraints;

[0008] According to the various constraints, the objective function is calculated to obtain the minimum value of the total operating cost of the power system in the target period, and the operating state of each power generation entity in the power system when the total operating cost is the minimum value is obtained, wherein each power generation entity includes a thermal power unit, a wind power unit and a photovoltaic unit;

[0009] According to the operating status of each power generation entity, the operating status of each power generation entity is adjusted in a cycle next to the target cycle.

[0010] In some possible implementations, the thermal power operation cost is the sum of the thermal power peak regulation cost and the thermal power start-up and shutdown cost;

[0011] The thermal power carbon trading cost is set to be the product of the carbon emissions purchased in the carbon market to meet the carbon emission standards and the carbon trading price in the carbon market;

[0012] Thermal power pollutants include multiple types of pollutants, and the thermal power pollutant emission cost is set to the sum of the emission costs of each type of pollutant, wherein the emission cost of each type of pollutant is the product of the unit emission cost of each type of pollutant and the emission coefficient of this type of pollution in the total thermal power generation and the unit power generation of thermal power.

[0013] The penalty cost for abandoning renewable energy and abandoned electricity is the sum of the penalty cost for abandoned wind power and the penalty cost for abandoned photovoltaic power;

[0014] The penalty cost for wind power curtailment is the sum of the first penalty costs at each moment in the preset duration, and the first penalty cost is the product of the difference between the maximum wind power generation power and the actual wind power grid-connected power and the penalty cost for wind power unit curtailment;

[0015] Among them, the penalty cost for photovoltaic power abandonment is the sum of the second penalty costs at each moment in the preset time period, and the second penalty cost is the product of the difference between the maximum photovoltaic power generation power and the actual photovoltaic grid-connected power and the penalty cost for photovoltaic unit power abandonment.

[0016] The energy storage system operating cost is set as the sum of the operating costs of each single discharge cycle of the energy storage devices in the energy storage system within the target period;

[0017] The single discharge cycle operating cost is the product of the cost of the energy storage device performing a charge and discharge cycle at a 100% discharge depth and the number of cycles converted to an equivalent number of cycles at a 100% discharge depth at a preset discharge depth.

[0018] The interruption load compensation cost is the product of the sum of the total load power provided by the interruptible load resources at the response terminal within a preset time period and the unit interruption power compensation coefficient of the interruptible load resources.

[0019] The backup constraint is set to that the sum of the backup power of the load, the backup power of the wind turbine generator set and the backup power of the photovoltaic generator set is less than or equal to the first parameter and the second parameter respectively;

[0020] Wherein, the first parameter is the difference between the maximum value outputted by the thermal power unit at the target time and the actual outputted by the thermal power unit at the target time;

[0021] The second parameter is the difference between the actual output of the thermal power unit at the target time and the minimum output of the thermal power unit at the target time.

[0022] The calculating the objective function according to the various constraints and the various operating costs includes:

[0023] The objective function and the various constraints are input into a preset solver for operation. If the operation result converges, the operation result includes the minimum value of the total operation cost of the power system within the target period.

[0024] According to a second aspect of an embodiment of the present disclosure, there is provided a power system cost optimization device, comprising: a function construction module, a constraint determination module, a function calculation module and a state adjustment module:

[0025] The function construction module is used to construct an objective function according to various operating costs during the operation of the power system, wherein the various operating costs include thermal power operation costs, thermal power pollutant emission costs, penalty costs for abandoned new energy and abandoned electricity, thermal power carbon trading costs, energy storage system operation costs and interrupted load compensation costs;

[0026] The constraint determination module is used to determine various constraint conditions during the operation of the power system to determine the load power of the power system at the target time, wherein the various constraint conditions include the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, the discharge power and charging power of the energy storage system at the target time, and the standby constraint;

[0027] The function calculation module is used to calculate the objective function according to the various constraints, obtain the minimum value of the total operating cost of the power system in the target period, and obtain the operating state of each power generation entity in the power system when the total operating cost is the minimum value, wherein the power generation entities include thermal power units, wind power units and photovoltaic units;

[0028] The state adjustment module is used to adjust the operating state of each power generation entity in the next cycle of the target cycle according to the operating state of each power generation entity.

[0029] According to a third aspect of an embodiment of the present disclosure, there is provided an electronic device, comprising a power output device and a memory for storing processor executable instructions, wherein the processor is configured to: execute the steps of the power system cost optimization method as described in the first aspect.

[0030] According to a fourth aspect of an embodiment of the present disclosure, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed, implements the steps of the power system cost optimization method as described in the first aspect.

[0031] The technical solution provided by the embodiments of the present disclosure may include the following beneficial effects: the power system cost optimization method in the present disclosure constructs an objective function according to the costs that need to be considered during the operation of the power system, and determines the constraints that need to be met during the operation of the power system; on the basis of satisfying the constraints, calculates the minimum operating cost of the power system within the target period, and obtains the operating status of each power generation entity in the power system when the operating cost is minimum; according to the operating status, adjusts each power generation entity in the power system in the next period to reduce the operating cost of the entire power system and realize the economical operation of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0033] Figure 1 The present invention is a flowchart of a method for optimizing power system cost according to an exemplary embodiment.

[0034] Figure 2 The present invention is a block diagram of a power system cost optimization device according to an exemplary embodiment. DETAILED DESCRIPTION

[0035] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0036] In the power system, the proportion of new resource power generation entities is increasing, and the construction of new power systems based on new energy is accelerating. Since new energy power resources such as wind power and photovoltaic power have great instability, it is necessary to improve the flexibility of the power system to cope with the randomness and instability of these renewable resources. In the process of improving the flexibility balance of the power system, the operating cost of the power system also increases.

[0037] In the process of building a new power system, while ensuring the stability of the system operation, the economic feasibility of the system operation should also be considered to ensure the sustainable and healthy development of the new power system. In order to ensure the sustainable development of the power system, it is necessary to optimize all aspects of the power system operation process.

[0038] To this end, the present disclosure provides a method for optimizing power system costs. Figure 1 is a flowchart of a method for optimizing power system cost according to an exemplary embodiment. Figure 1 , power system cost optimization methods include:

[0039] Step S11, constructing an objective function according to various operating costs during the operation of the power system, wherein the various operating costs include thermal power operation costs, thermal power pollutant emission costs, penalty costs for abandoning new energy and power, thermal power carbon trading costs, energy storage system operation costs and interrupted load compensation costs.

[0040] Step S12, determining various constraints during the operation of the power system to determine the load power of the power system at the target time, wherein the various constraints include the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, the discharge power and charging power of the energy storage system at the target time, and standby constraints.

[0041] Step S13, calculating the objective function according to the various constraints, obtaining the minimum value of the total operating cost of the power system within the target period, and obtaining the operating status of each power generation entity in the power system when the total operating cost is the minimum value, wherein the power generation entities include thermal power units, wind power units and photovoltaic units.

[0042] Step S14, adjusting the operating status of each power generation entity in a cycle next to the target cycle according to the operating status of each power generation entity.

[0043] In step S11, during the overall stable operation of the power system, various types of costs are involved, such as thermal power operation costs, thermal power pollutant emission costs, penalty costs for abandoned new energy and abandoned electricity, thermal power carbon trading costs, energy storage system operation costs, and interrupted load compensation costs. Based on these costs, an objective function is constructed, which is used to represent the total cost required by the entire power system during operation. For example, the objective function can be constructed as follows:

[0044]

[0045] Among them C all Represents the overall operating cost of the power system; C TP represents the operating cost of thermal power; C W is the cost of pollutant emissions from thermal power generation; C Q It represents the penalty cost for abandoning renewable energy and electricity; represents the carbon trading cost; C jl represents the interruption load compensation cost; C c Represents the operating cost of the energy storage system. This formula is combined with the subsequent constraints to calculate the minimum operating cost of the power system as a whole, i.e., minC all .

[0046] Among them, the thermal power operation cost refers to the cost consumed by the thermal power units in the power system during operation, which can include the thermal power peak regulation cost and the thermal power start-up and shutdown cost. Thermal power peak regulation refers to controlling the thermal power generation according to the electricity demand, and its cost can be expressed by the following formula:

[0047]

[0048]

[0049] Among them C m ,i, t Refers to the power generation cost of a thermal power unit i at a certain time t, where P i , t It represents the output of thermal power unit i at time t, that is, the power generated at that time. i , b i , c i is the coal consumption characteristic coefficient of thermal power unit i, which can be set according to the specific conditions of the thermal power unit; C mIt refers to the operating cost of all thermal power units within the target cycle T, that is, the power generation cost of all thermal power units at a certain time t is obtained, and then the power generation cost of all thermal power units within the entire target cycle T is summed. I refers to all thermal power units in the power system. The target cycle T is generally 24 hours. The time t can refer to a specific hour, because the specific formula in the present disclosure is to sum the cost obtained for each t when calculating, so the time t is equivalent to a time period. For example, t=1 can refer to the first hour. By calculating the cost required for each hour, each t in the total target cycle T, that is, each hour within 24 hours, is summed. Of course, the unit of the time t can also be half an hour, one minute or even one second, which can be set according to actual conditions.

[0050] The start-stop cost of thermal power refers to the cost required to switch a thermal power unit from a stopped state to an on state during the operation of the power system, which can be expressed by the following formula:

[0051]

[0052] Among them C u represents the start-up and shutdown costs of all thermal power units during operation, z i，t Indicates whether the thermal power unit is in the on state or the off state at time t. When the thermal power unit is in the on state, it takes 1, and when the thermal power unit is in the off state, it takes 0; z i，t-1 is the corresponding state of the thermal power unit at time t-1; i，t (1-z i，t-1 ) means that if the thermal power unit was in shutdown state at the last moment, that is, z i，t-1 is 0, and is in the power-on state at the current moment, i.e. z i，t is 1, then it is necessary to start the thermal power unit, z i，t (1-z i，t-1 ) is 1, which is equivalent to calculating the start-stop cost once. i It is expressed as the cost of a single start and stop. By calculating the start and stop costs of all units at time t and summing them up over the entire target period, we can get C u , that is, the start-up and shutdown costs of the entire thermal power unit within the target cycle are obtained.

[0053] The operating cost of a thermal power unit can be expressed by the following formula:

[0054] C TP =C m +C u

[0055] Among them C TP Expressed as the operating cost of thermal power units, Cm is the peak load regulation cost of thermal power units, C u is the start-up and shutdown cost of the thermal power unit. Through this formula and the above specific calculation formula, the operating cost of the entire thermal power unit in the target period T can be obtained.

[0056] The pollutant emission cost of thermal power generation refers to the cost required to discharge pollutants generated during the operation of thermal power units. The specific calculation formula is as follows:

[0057]

[0058] Among them, C W Refers to the cost of pollutant emissions from thermal power generation, c w,k Refers to the cost per unit of emission of the kth type of pollutant, P M Refers to the total power generation of thermal power in the entire target period, β k Refers to the emission coefficient of the kth type of pollutant in the unit power generation of thermal power, which can be understood as the emission of the kth type of pollutant generated by the unit power generation of thermal power. This formula can be used to calculate the amount of various pollutants generated by the total emission of thermal power, and multiply it by the cost required for the unit emission of various pollutants, and then sum the costs required for the emission of various pollutants, and finally get the total cost of thermal power pollutant emissions, that is, C W .

[0059] The carbon trading cost of thermal power refers to the product of the carbon emissions purchased in the carbon market to meet the carbon emission standards and the carbon trading price in the carbon market. Thermal power units will emit carbon during operation, so it is necessary to purchase a certain amount of carbon quotas in the carbon market to compensate for the carbon emissions caused. The specific calculation formula is as follows:

[0060]

[0061] in, is the carbon trading cost. CT refers to the carbon emissions purchased in the carbon market to meet the carbon emission standards. Its specific value is related to the total power of the thermal power unit in the target period. c It is the price of carbon trading in the carbon market.

[0062] The penalty cost for abandoning renewable energy includes the penalty cost for abandoned wind power and the penalty cost for abandoned photovoltaic power. For example, the actual maximum power generation of wind power is 10,000W, but the actual grid power is only 7,000W, which is equivalent to abandoning 3,000W of power generation. Therefore, a penalty is required. The specific penalty cost is the product of the penalty cost for abandoned wind power per unit and the total abandoned wind power. The penalty for abandoned photovoltaic power generation is the product of the penalty cost for abandoned photovoltaic per unit and the total abandoned photovoltaic power. The specific formula for the penalty cost for abandoned renewable energy is as follows:

[0063]

[0064] Among them, C Q The penalty cost for abandoning renewable energy and electricity, θ f is the penalty cost for wind power unit curtailment, θ g P is the penalty cost for photovoltaic power abandonment; f.t , P g,t Respectively represent the maximum power generation of wind power and photovoltaic power at the moment; P F,t , P G,t They represent the actual grid-connected power of wind power and photovoltaic power at time t respectively.

[0065] The penalty cost of wind power curtailment is the sum of the first penalty costs at each moment in the preset duration. The first penalty cost is the product of the difference between the maximum wind power generation power and the actual wind power grid-connected power and the penalty cost of wind power unit curtailment, that is, θ f (P f.t -P F,t ).

[0066] The penalty cost of photovoltaic power abandonment is the sum of the second penalty cost at each moment in the preset duration. The second penalty cost is the product of the difference between the maximum photovoltaic power generation power and the actual photovoltaic grid-connected power and the penalty cost of photovoltaic unit power abandonment, that is, θ g (P g,t -P G,t ).

[0067] The operating cost of the energy storage system refers to the sum of the operating costs of each single-discharge cycle of the energy storage equipment in the energy storage system within the target period, wherein the operating cost of a single discharge cycle is the product of the cost of the energy storage device performing a charge and discharge cycle at 100% discharge depth and the number of cycles converted to the equivalent number of cycles at 100% discharge depth at the preset discharge depth. During the operation of the power system, the energy storage equipment of the energy storage system also assumes the functions of receiving and generating electricity, and the energy storage equipment will generate losses in the process of power generation. This loss cost is the operating cost of the energy storage system. The specific calculation method is as follows:

[0068]

[0069]

[0070]

[0071] where c DOD,E The calculation is the cost required for the energy storage device to perform a charge and discharge cycle with a 100% discharge depth, m p 、m yare the investment and construction cost and operation and maintenance cost per unit power of battery energy storage, m s P is the investment and construction cost per unit capacity of battery energy storage; NC , S NC are the rated power and rated capacity of the battery energy storage configuration; N E It is the number of cycles when the battery energy storage reaches the end of its life at 100% discharge depth. The total construction cost of the battery energy storage equipment is divided by the total number of cycles to get the cost of a charging cycle with 100% discharge depth.

[0072] N eq,k It means that when the energy storage device is at a discharge depth of D DOD , k The number of cycles at the time of discharge is converted to the equivalent number of cycles at 100% discharge depth, N S (D DOD,k ) refers to the DODk The equivalent number of cycles is calculated as follows: the number of cycles when the battery energy storage device reaches the end of its life at 100% discharge depth, divided by the number of cycles when the battery energy storage device reaches the end of its life at D DODk The number of cycles to reach the end of life under the discharge depth, n is the cumulative number of charge and discharge cycles of the battery energy storage within the target period.

[0073] The cost of each charge and discharge is obtained by multiplying the equivalent number of charge and discharge cycles by the cost of each 100% deep charge and discharge cycle. The cost of each charge and discharge in the target cycle is summed up to finally obtain the total operating cost of the energy storage system in the target cycle.

[0074] The interruption load compensation cost is the product of the sum of the total load power provided by the interruptible load resources at the response terminal within the preset time and the unit interruption power compensation coefficient of the interruptible load resources. The specific calculation formula is as follows:

[0075]

[0076] where c jl,t is the unit interruption power compensation coefficient of the interruptible load resource at time t, P jl,i,t represents the interruption load power provided by a certain interruptible load resource i, Δt is the time to respond to the interruption, u jl,t It is a binary 0-1 variable. The value of 1 indicates that the i-th interruptible load resource responds to the interrupt at time t, and the value of 0 indicates that no response interrupt occurs at this moment. n refers to all interruptible load resources. By calculating the interruption load power provided by each interruptible load resource in the target period and multiplying it by its corresponding compensation coefficient, the cost to be compensated is finally obtained.

[0077] Regarding interruptible loads, it is an incentive-based demand response method that uses the interrupted power provided by the user to meet the system's operating needs by compensating for the interrupted power provided by the user. The response model of interruptible load resources is:

[0078]

[0079] in, is the power required by the interruptible load resource after responding, is the power required before response, It is equivalent to the interruptible load resources contributing power by reducing the power they need for use by other demand sides in the power system.

[0080] The above content is the specific calculation method of various operating costs in this disclosure. Through the specific calculation formulas and objective functions of various costs, the total operating cost of the power system within the target period can be calculated.

[0081] In step S12, various constraints that need to be met during the operation of the power system are determined. These constraints are used to determine the load power during the operation of the power system at the target time. These constraints include: the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, the discharge power and charging power of the energy storage system at the target time, and standby constraints.

[0082] Among them, the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, and the discharge power and charging power of the energy storage system at the target time should meet the following constraints:

[0083] P TP,t +P F,t +P G,t +(P cf,t -P ch,t )=P l,t

[0084] Where P TP,t represents the power generation output of thermal power at time t; P F,t and P G,t are the power generation output of wind power and photovoltaic power at time t, which mainly depends on the natural wind and photovoltaic radiation intensity; P cf,t and P ch,t represents the discharge and charge power of the energy storage at time t; P l,t Represents the load power at time t. The purpose of this constraint is to ensure that the power generated by the power system is equal to the power required by the electricity user.

[0085] At the same time, the constraints on thermal power generation output also include:

[0086] P TP,min ≤P TP,t ≤P TP,max

[0087] Among them, P TP,max and P TP,min They are the maximum output and minimum output of the thermal power unit, which can be determined based on the historical output of the thermal power unit.

[0088] The thermal power unit should also meet the constraint that the thermal power unit should meet the climbing constraint. The specific formula is as follows:

[0089] U TP,t-1 P TP,t-1 -α dTP ≤P TP,t ≤U TP,t-1 P TP,t-1 +α uTP

[0090] Among them U TP,t-1 The start and stop status of the thermal power unit at the previous moment of the current moment, with 0 representing the stop state and 1 representing the start state. TP,t-1 refers to the power output of the thermal power unit at time t-1, α dTP and α uTP They represent the climbing rate limit values ​​of the thermal power unit climbing downward and climbing upward respectively. The climbing of the thermal power unit can be understood through an example. The output power of the thermal power at the previous moment is 1000w. If it needs to reach 1500w at the current moment, it is climbing upward. If it needs to reach 500w at the current moment, it is climbing downward. The climbing rate limit value refers to the maximum value that the difference between the previous and next moments can reach when climbing.

[0091] Thermal power units should also meet the start-stop constraints. The specific formula is as follows:

[0092]

[0093]

[0094] in, and are the continuous operation time and continuous shutdown time of the thermal power unit in the t-1 period respectively; T onTP and T offTP are the minimum continuous operation time and minimum shutdown time of thermal power units, U TP,tRefers to the start and stop state of the thermal power unit at time t. Generally, the thermal power unit is always in the start state during operation, so the above formula is in a constant state. However, when the running time at the previous moment is less than the minimum running time, and it was in the start state at the previous moment, it should also be in the start state at the current moment; if the shutdown time at the previous moment is less than the minimum shutdown time, and it was in the shutdown state at the previous moment, it should also be in the shutdown state at the current moment.

[0095] The operation constraints of energy storage equipment should be met during the operation of energy storage equipment. The specific constraints are as follows:

[0096]

[0097] μ1S NC ≤S t ≤μ2S NC

[0098] S t =S t-1 +[P ch,t η ch -P cf,t / η cf ]Δt

[0099] Where P cf,t and P ch,t Respectively represent the power generation and charging power of the energy storage device at time t; P NC Indicates the rated power of energy storage; μ cf and μ c h are all 0-1 variables, μ cf When the value is 1, it means that the energy storage is in the power generation state at this moment, and when the value is 0, it means that the energy storage is not in the power generation state at this moment. The variable representing the charging state of the energy storage, μ c h is the same. The above formula is used to constrain that the energy storage device can only be in one of the states of charging and discharging, and cannot be charged and discharged at the same time, and the charging power and discharging power cannot be greater than the rated power, and the amount of electricity in the energy storage device cannot exceed the upper and lower limits. t Indicates the state of charge of the battery energy storage at time t, that is, the amount of electricity inside the battery energy storage device at time t; S NC Represents the rated capacity of the energy storage device; μ1 and μ2 are the lower and upper coefficients of the inherent state of charge of the energy storage device; η cf,t and η c h ,t They represent the discharge efficiency coefficient and charging efficiency coefficient of the energy storage at time t, respectively, and are used to calculate the internal charge of the energy storage device at the current moment.

[0100] The constraints that the terminal power provided by the interruptible response resources in the power system should meet are as follows:

[0101] u jl,t P jl,i,t，min ≤P jl,i,t ≤u jl,t P jl,i,t，max

[0102] Where P jl,i,t，min and P jl,i,t，max The upper and lower limits of the interruption load power that can be provided by a certain interruptible load resource i can be set according to the specific situation.

[0103] Finally, in order to ensure stable operation, the power system also needs to increase a certain amount of reserve capacity to deal with errors and emergencies. The reserve constraint is set as follows: the sum of the reserve power of the load, the reserve power of the wind turbine and the reserve power of the photovoltaic unit is less than or equal to the first parameter and the second parameter respectively; wherein the first parameter is the difference between the maximum value output of the thermal power unit at the target time and the actual output of the thermal power unit at the target time; the second parameter is the difference between the actual output of the thermal power unit at the target time and the minimum value output of the thermal power unit at the target time. The specific constraint formula is as follows:

[0104]

[0105] where s d ,s f and g They are the reserve rates of load, wind turbine and photovoltaic units. Reserve power refers to the power that the unit can provide under special circumstances, which can be understood as a power output capacity. The reserve power of the load refers to the power that the load end can provide by reducing demand.

[0106] In step S13, according to the various constraints in the above process, the objective function is calculated to obtain the minimum value of the objective function within the target period, that is, the minimum value of the total operating cost of the power system within the target period. At the same time, the operating status of each subject corresponding to the minimum operating cost is obtained, for example, the output of the thermal power unit, the output of the wind power unit, the output of the photovoltaic power unit, the power that can be provided by the interruptible load resources and other information.

[0107] In one example, the objective function and the various constraints can be input into a preset solver. For example, various formulas are encoded in python, and the Gurobi solver is used for calculation and solution. If the operation results converge, the calculation results include the minimum value of the total operating cost of the power system in the target period, and also include the specific power generation conditions within the power system such as the output power of the thermal power unit and the output power of the wind power unit. The Gurobi solver supports parallel computing and definite calculation results; it also supports multiple development methods and multi-platform development, with less memory consumption, and it is more convenient and faster to solve and calculate through the solver.

[0108] In step S14, the operating status of each power generation subject in the next cycle is adjusted according to the operating status of each power generation subject obtained in step S13. For example, the power generation power of the thermal power unit obtained in step S13 when the total operating cost of the power system in the target cycle is the smallest is 10,000W per hour in the morning and 30,000W per hour in the afternoon. Then, in the next cycle, the operating status of the thermal power unit is adjusted with reference to the power generation situation. The same is true for other power generation subjects. This example is only used for explanation, and its specific power generation status is determined by the calculation result. It should be noted that the operating status of each subject obtained in the target cycle is only a basis for adjusting the next cycle, and the specific operating status of the next cycle should be determined according to the actual situation. Since the operating status of each subject in the next cycle is adjusted based on the operating status of each subject when the total operating cost of the target cycle is the smallest, the operating cost of the power system in the next cycle can be effectively reduced.

[0109] Through the above embodiments, a power system cost optimization method provided in this article constructs an objective function according to various types of costs required during the operation of the power system, and determines the constraints that need to be considered during the operation of the power system. The minimum value of the objective function is determined on the basis of satisfying the constraints, and the minimum cost required for the power system to operate within the target cycle is obtained. At the same time, the operating status of each subject in the power system at this time is obtained, and according to the operating status of each subject, each subject in the power system is adjusted in the next cycle of the target cycle, which can effectively reduce the overall operating cost of the power system and improve the operating economy of the power system.

[0110] Figure 2 is a block diagram of a power system cost optimization device according to an exemplary embodiment. Figure 2 The power system cost optimization device includes: a function construction module 201, a constraint determination module 202, a function calculation module 203 and a state adjustment module 204.

[0111] The function construction module 201 is configured to construct an objective function according to various operating costs during the operation of the power system, wherein the various operating costs include thermal power operation costs, thermal power pollutant emission costs, penalty costs for abandoning new energy and power, thermal power carbon trading costs, energy storage system operation costs and interrupted load compensation costs.

[0112] The constraint determination module 202 is configured to determine various constraint conditions during the operation of the power system to determine the load power of the power system at the target time, wherein the various constraint conditions include the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, the discharge power and charging power of the energy storage system at the target time, and standby constraints.

[0113] The function calculation module 203 is configured to calculate the objective function according to the various constraints, obtain the minimum value of the total operating cost of the power system within the target period, and obtain the operating status of each power generation entity in the power system when the total operating cost is the minimum value, wherein the power generation entities include thermal power units, wind power units and photovoltaic units.

[0114] The state adjustment module 204 is configured to adjust the operating state of each power generation entity in the next cycle of the target cycle according to the operating state of each power generation entity.

[0115] The present disclosure also provides an electronic device, which includes a processor and a memory for storing processor executable instructions, and the processor is configured to: execute the steps of the power system cost optimization method recorded in any embodiment of the present disclosure.

[0116] The present disclosure also provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed, the steps of the power system cost optimization method recorded in any embodiment of the present disclosure are implemented.

[0117] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed in this disclosure. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0118] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A method for optimizing power system cost, characterized in that: The method comprises: According to various operating costs in the operation of the power system, an objective function is constructed, wherein the various operating costs include thermal power operation cost, thermal power pollutant emission cost, penalty cost for abandoned new energy and abandoned electricity, thermal power carbon trading cost, energy storage system operation cost and interrupted load compensation cost; Determine various constraints during the operation of the power system to determine the load power of the power system at the target time, wherein the various constraints include the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, the discharge power and charging power of the energy storage system at the target time, and standby constraints; According to the various constraints, the objective function is calculated to obtain the minimum value of the total operating cost of the power system in the target period, and the operating state of each power generation entity in the power system when the total operating cost is the minimum value is obtained, wherein each power generation entity includes a thermal power unit, a wind power unit and a photovoltaic unit; According to the operating status of each power generation entity, the operating status of each power generation entity is adjusted in a cycle next to the target cycle.

2. The method according to claim 1, characterized in that The thermal power operation cost is the sum of the thermal power peak regulation cost and the thermal power start-up and shutdown cost; The thermal power carbon trading cost is set to be the product of the carbon emissions purchased in the carbon market to meet the carbon emission standards and the carbon trading price in the carbon market; Thermal power pollutants include multiple types of pollutants, and the thermal power pollutant emission cost is set to the sum of the emission costs of each type of pollutant, wherein the emission cost of each type of pollutant is the product of the unit emission cost of each type of pollutant and the emission coefficient of this type of pollution in the total thermal power generation and the unit power generation of thermal power.

3. The method according to claim 1, characterized in that The penalty cost for abandoning renewable energy and abandoned electricity is the sum of the penalty cost for abandoned wind power and the penalty cost for abandoned photovoltaic power; The penalty cost for wind power curtailment is the sum of the first penalty costs at each moment in the preset duration, and the first penalty cost is the product of the difference between the maximum wind power generation power and the actual wind power grid-connected power and the penalty cost for wind power unit curtailment; Among them, the penalty cost for photovoltaic power abandonment is the sum of the second penalty costs at each moment in the preset time period, and the second penalty cost is the product of the difference between the maximum photovoltaic power generation power and the actual photovoltaic grid-connected power and the penalty cost for photovoltaic unit power abandonment.

4. The method according to claim 1, characterized in that: The energy storage system operating cost is set as the sum of the operating costs of each single discharge cycle of the energy storage devices in the energy storage system within the target period; The single discharge cycle operating cost is the product of the cost of the energy storage device performing a charge and discharge cycle at a 100% discharge depth and the number of cycles converted to an equivalent number of cycles at a 100% discharge depth at a preset discharge depth.

5. The method according to claim 1, characterized in that The interruption load compensation cost is the product of the sum of the total load power provided by the interruptible load resources at the response terminal within a preset time period and the unit interruption power compensation coefficient of the interruptible load resources.

6. The method according to claim 1, characterized in that The backup constraint is set to that the sum of the backup power of the load, the backup power of the wind turbine generator set and the backup power of the photovoltaic generator set is less than or equal to the first parameter and the second parameter respectively; Wherein, the first parameter is the difference between the maximum value outputted by the thermal power unit at the target time and the actual outputted by the thermal power unit at the target time; The second parameter is the difference between the actual output of the thermal power unit at the target time and the minimum output of the thermal power unit at the target time.

7. The method according to claim 6, characterized in that: The calculating the objective function according to the various constraints and the various operating costs includes: The objective function and the various constraints are input into a preset solver for operation. If the operation result converges, the operation result includes the minimum value of the total operation cost of the power system within the target period.

8. A power system cost optimization device, characterized in that: The device comprises: a function construction module, a constraint determination module, a function calculation module and a state adjustment module: The function construction module is used to construct an objective function according to various operating costs during the operation of the power system, wherein the various operating costs include thermal power operation costs, thermal power pollutant emission costs, penalty costs for abandoned new energy and abandoned electricity, thermal power carbon trading costs, energy storage system operation costs and interrupted load compensation costs; The constraint determination module is used to determine various constraint conditions during the operation of the power system to determine the load power of the power system at the target time, wherein the various constraint conditions include the power generation output of thermal power at the target time, the power generation output of wind power at the target time, the power generation output of photovoltaic power at the target time, the discharge power and charging power of the energy storage system at the target time, and the standby constraint; The function calculation module is used to calculate the objective function according to the various constraints, obtain the minimum value of the total operating cost of the power system in the target period, and obtain the operating state of each power generation entity in the power system when the total operating cost is the minimum value, wherein the power generation entities include thermal power units, wind power units and photovoltaic units; The state adjustment module is used to adjust the operating state of each power generation entity in the next cycle of the target cycle according to the operating state of each power generation entity.

9. An electronic device, characterized in that: The electronic device comprises a processor and a memory for storing processor executable instructions, and the processor is configured to: execute the steps of the power system cost optimization method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the steps of the power system cost optimization method according to any one of claims 1 to 7 are implemented.

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