A flexible incentive method for ensuring real-time balance of power system

Abstract

This invention discloses a flexibility incentive method for ensuring real-time power system balance, belonging to the field of power system real-time balancing technology. It includes: one week before real-time operation, renewable energy entities and flexibility entities conduct autonomous coordination based on predictable renewable energy deviations, with flexibility entities reserving flexible adjustment space in advance. When renewable energy entities face power supply shortages or curtailment risks due to prediction deviations, flexibility entities utilize reserved adjustment capacity to balance renewable energy output deviations; 30 minutes before real-time operation, the remaining deviation is calculated and centrally balanced; a day-ahead energy-flexibility joint optimization model for renewable energy across provinces / regions is constructed; power delivery is performed; and after real-time power delivery, imbalance settlement is conducted based on the utilization of flexibility resources. This invention can incentivize flexibility entities to autonomously provide flexible adjustment capabilities while reducing the pressure on real-time system balance; it is beneficial for directly alleviating the pressure on real-time power system balance.

Description

Technical Field

[0001] This invention relates to the field of real-time power system balancing technology, and in particular to a flexible incentive method for ensuring real-time power system balancing. Background Technology

[0002] China's resource endowment and energy demand are inversely distributed, making the optimized allocation of new energy resources on a larger scale an inherent requirement for the construction of China's new power system. As the share of new energy generation transmitted between provinces continues to increase, its inherent random fluctuations in power generation have led to a significant year-on-year increase in the scale of new energy power deviation. To address this, during the real-time operation phase, a unified purchase of flexibility services is used to balance system power deviation, ensuring real-time system power balance. New energy entities fulfill their economic responsibility for deviation balancing through imbalance settlements but do not participate in the physical deviation balancing process. Considering the importance of power supply and demand balance for system security, this centralized balancing management model has the advantage of ensuring the efficiency and robustness of the deviation balancing process. However, with the continuous growth of power deviation under a high proportion of new energy power systems, the centralized balancing model will significantly increase the pressure on real-time system balancing.

[0003] Currently, there is limited research on power balance management under high-proportion renewable energy integration. Existing balance management methods mainly rely on unified scheduling of flexible resources to balance the uncertainty of renewable energy output, ensuring real-time system power balance. For example, Chinese patent CN117878941A describes a power system scheduling method and device that considers decision-dependent uncertainty. By constructing and solving long-term and real-time scheduling models, it fully considers the decision-dependent uncertainty of flexible load incentive response, achieving long-term real-time power balance of the power system. However, the uncertainty brought about by high-proportion renewable energy leads to a year-on-year increase in system deviation, significantly increasing the demand for flexible adjustment resources. This balance management method weakens the vitality of renewable energy entities in deviation reduction, putting significant pressure on the system to achieve real-time balance.

[0004] Therefore, a flexible incentive method is needed to ensure the real-time balance of the power system and fully incentivize flexible resources to autonomously provide regulation capabilities in order to address the surge in real-time balance pressure caused by the uncertainty of high proportion of new energy sources. Summary of the Invention

[0005] The purpose of this invention is to propose a flexible incentive method to ensure real-time balance of a power system, comprising the following steps:

[0006] Step 1: One week before real-time operation, the renewable energy entity and the flexible energy entity conduct autonomous coordination based on the foreseeable renewable energy deviation. The flexible energy entity reserves flexible adjustment space in advance. When the renewable energy entity faces the risk of insufficient power supply or curtailment due to prediction deviation, the flexible energy entity uses the reserved adjustment capacity to balance the renewable energy output deviation.

[0007] Step 2: In the first 30 minutes of real-time operation, calculate the remaining deviation based on the actual system deviation and the flexibility reserve of autonomous coordination, and then perform centralized balancing of the remaining deviation.

[0008] Step 3: Construct a day-ahead power-flexibility joint optimization model for new energy sources across provinces and regions to achieve coordinated and optimized operation of inter-provincial power transmission and flexibility reserves;

[0009] Step 4: Conduct power handover;

[0010] Step 5: After the real-time power delivery, perform imbalance settlement based on the availability of flexible resources.

[0011] The joint optimization model for power and flexibility in step 3 includes:

[0012] Objective function:

[0013]

[0014] In the formula, F E With F R These represent the model's total energy and flexibility, respectively; P t,n With λ t,n These are the electrical energy and energy coefficient of the main renewable energy source; P t,c With λ t,c These refer to the main electrical energy of thermal power plants and their energy coefficients; and These refer to adjusting the flexibility of the main body of thermal power plants and their flexibility coefficients. and These refer to the reduction of flexibility of the main body of thermal power plants and their flexibility coefficients; and These refer to adjusting the flexibility of the energy storage entity and its flexibility coefficient. and These refer to adjusting the flexibility of the energy storage entity and its flexibility coefficient.

[0015] Constraints:

[0016] Power balance constraints

[0017]

[0018] In the formula, P t To meet the needs of inter-provincial power transmission, ξl Transmission loss due to inter-provincial communication lines;

[0019] Inter-provincial channel transmission capacity constraints

[0020]

[0021] In the formula, A l This represents the maximum transmittable capacity of the inter-provincial transmission channel.

[0022] Inter-provincial renewable energy transmission ratio constraints

[0023]

[0024] In the formula, ε is the minimum new energy transmission ratio required for inter-provincial transmission channels;

[0025] Flexibility Balance Constraints

[0026]

[0027] In the formula, and These refer to the flexibility of autonomous and coordinated upward and downward adjustments; and These refer to the flexibility of adjusting unified reserves both upwards and downwards; and These refer to the flexibility requirements for inter-provincial adjustments, both upward and downward.

[0028] Renewable energy output constraints

[0029] 0≤P t,n ≤P n,max

[0030] In the formula, P n,max This is the upper limit for inter-provincial power transmission, which is the main source of new energy sources.

[0031] Power generation capacity constraints

[0032]

[0033] In the formula, P c,min This is the lower limit of the generating capacity of thermal power units; Apply for inter-provincial power transmission limits for thermal power plants;

[0034] Flexibility and capacity constraints

[0035]

[0036] In the formula, P c,max This is the upper limit of the generating capacity of thermal power units;

[0037] Thermal power plant ramping constraints

[0038]

[0039] In the formula, and These are the upper limits of the uphill and downhill ramp rates for thermal power units, respectively.

[0040] Charge and discharge power constraints

[0041]

[0042] In the formula, and Let P be the 0 and 1 variables representing the charge and discharge states of the energy storage device, respectively; s,max η is the upper limit of the charging and discharging power of energy storage devices. s To improve the charging and discharging efficiency of energy storage devices;

[0043] Charge and discharge capacity constraints

[0044]

[0045] 0≤Q t,s ≤Q s,max

[0046]

[0047] In the formula, Q t,s The energy stored in the energy storage device at time t; Q s,max This represents the maximum storage capacity of the energy storage device.

[0048] Step 4 specifically includes: During the power delivery process, when new energy entities face insufficient power supply or the risk of power curtailment due to uncertainties in power generation, the flexibility entity compensates for the deviation generated by the new energy entities during the real-time delivery process; in terms of flexibility call selection, priority is given to calling the flexibility reserves of new energy entities through self-coordination to balance; if the self-coordination flexibility reserves are insufficient to cover the deviation of new energy, the flexibility service of unified reserves is called to balance the remaining deviation.

[0049] The beneficial effects of this invention are as follows:

[0050] 1. This invention can incentivize flexible entities to autonomously provide flexible adjustment capabilities while reducing the real-time balancing pressure on the system; at the same time, new energy entities can reduce system deviations in advance through autonomous coordination, which is beneficial to directly reduce the real-time balancing pressure on the power system.

[0051] 2. This invention can compensate for system deviations during real-time operation, ensuring the robustness of the power system balance management process.

[0052] 3. The flexible incentive method of the present invention is simple to operate and has high adaptability to current balancing methods. Attached Figure Description

[0053] Figure 1 This is a flowchart of a flexible incentive method for ensuring real-time balance of a power system according to the present invention;

[0054] Figure 2 A schematic diagram of a flexible incentive method for autonomous coordination and unified reserves. Detailed Implementation

[0055] This invention proposes a flexible incentive method to ensure the real-time balance of a power system. The invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0056] Figure 1 This is a flowchart of a flexibility incentive method for ensuring real-time power system balance according to the present invention. The flexibility incentive method for ensuring real-time power system balance in this embodiment includes two parts: First, before real-time operation, new energy entities and flexibility entities autonomously conduct flexibility reserves to pre-balance the foreseeable new energy deviations; this is called autonomous flexibility coordination. Second, since the true scale of system deviations cannot be determined, the flexibility services provided by the autonomous flexibility coordination reserves may not fully cover the actual system deviations, i.e., there is a "residual" deviation. Compensating for this residual deviation is called unified flexibility reserves.

[0057] The implementation steps of the flexibility incentive method include: 1. One week before real-time operation, the new energy entity and the flexibility entity carry out autonomous coordination of flexibility based on the foreseeable new energy deviation. The flexibility entity reserves flexible adjustment space in advance. When the new energy entity faces the risk of insufficient power supply or curtailment due to prediction deviation, the flexibility entity uses the reserved adjustment capacity to balance the new energy output deviation.

[0058] 2. In the first 30 minutes of real-time operation, consider the flexibility requirements caused by the uncertainty of new energy sources to organize inter-provincial power transmission. Calculate the remaining deviation based on the actual system deviation and the flexibility reserve of autonomous coordination, and centrally balance the remaining deviation during the real-time operation phase.

[0059] 3. The proposed "autonomous coordination + unified reserve" flexibility incentive method is incorporated into the inter-provincial power transmission model to construct a joint optimization model of new energy inter-provincial day-ahead power energy and flexibility, so as to realize the coordinated optimization operation of inter-provincial power transmission and flexibility reserve. Figure 2 A schematic diagram of a flexible incentive method for autonomous coordination and unified reserves.

[0060] 1) Objective function

[0061]

[0062] In the formula, F E With F R These represent the model's total energy and flexibility, respectively; P t,n With λ t,n These are the electrical energy and energy coefficient of the main renewable energy source; P t,c With λ t,c These refer to the main electrical energy of thermal power plants and their energy coefficients; and These refer to adjusting the flexibility of the main body of thermal power plants and their flexibility coefficients. and These refer to the reduction of flexibility of the main body of thermal power plants and their flexibility coefficients; and These refer to adjusting the flexibility of the energy storage entity and its flexibility coefficient. and These refer to adjusting the flexibility of the energy storage entity and its flexibility coefficient.

[0063] 2) Constraints

[0064] 2-1) Power balance constraints

[0065] The power output of inter-provincial generator sets needs to meet the electricity load demand.

[0066]

[0067] In the formula, P t To meet the needs of inter-provincial power transmission, ξ l This refers to the transmission loss of inter-provincial communication lines.

[0068] 2-2) Inter-provincial channel transmission capacity constraints

[0069] The power transmission capacity between provinces shall not exceed the available transmission capacity of the inter-provincial channel.

[0070]

[0071] In the formula, A l This represents the maximum transmittable capacity of the inter-provincial transmission channel.

[0072] 2-3) Inter-provincial renewable energy transmission ratio constraints

[0073] The proportion of new energy transmission between provinces shall not be lower than the proportion of new energy transmission required by inter-provincial power transmission channels.

[0074]

[0075] In the formula, ε is the minimum new energy transmission ratio required for inter-provincial transmission channels.

[0076] 2-4) Flexibility Balance Constraints

[0077] The flexibility of independent coordination and unified reserves needs to meet the requirements of inter-provincial flexibility adjustment.

[0078]

[0079] In the formula, and These refer to the flexibility of autonomous and coordinated upward and downward adjustments; and These refer to the flexibility of adjusting unified reserves both upwards and downwards; and These are respectively the flexibility requirements for inter-provincial adjustments.

[0080] 2-5) Renewable energy output constraints

[0081] The electrical energy of new energy generating units must not exceed their power generation capacity limit.

[0082] 0≤P t,n ≤P n,max

[0083] In the formula, P n,max This is the upper limit for inter-provincial power transmission, which is the main source of new energy.

[0084] 2-6) Power generation capacity constraints of thermal power units

[0085] 2-6-1) Power generation capacity constraints

[0086] The electrical energy of thermal power units must not exceed their power generation capacity limit.

[0087]

[0088] In the formula, P c,min This is the lower limit of the generating capacity of thermal power units; This is the upper limit for inter-provincial power transmission of thermal power plants.

[0089] 2-6-2) Flexibility Capacity Constraints

[0090] Thermal power units use the remaining output capacity of inter-provincial electrical energy as the upper and lower limits of their flexibility capacity.

[0091]

[0092] In the formula, P c,max This is the upper limit of the generating capacity of thermal power units.

[0093] 2-6-3) Thermal power plant ramping constraints

[0094] The increase or decrease in output of thermal power units in adjacent time periods shall not exceed the ramp-up rate of the thermal power units.

[0095]

[0096] In the formula, and These are the upper limits for the uphill and downhill climbing speeds of thermal power units, respectively.

[0097] 2-7) Constraints of Energy Storage Equipment

[0098] 2-7-1) Charge and discharge power constraints

[0099] The charging and discharging power of the storage equipment must not exceed the maximum charging and discharging power, and charging and discharging must not be performed simultaneously during the adjustment process.

[0100]

[0101] In the formula, and Let P be the 0 and 1 variables representing the charge and discharge states of the energy storage device, respectively; s,max η is the upper limit of the charging and discharging power of energy storage devices. s The charging and discharging efficiency of energy storage devices.

[0102] 2-7-2) Charge / discharge capacity constraints

[0103] The cumulative charge and discharge of an energy storage device at any given time must not exceed its maximum storage capacity.

[0104]

[0105] 0≤Q t,s ≤Q s,max

[0106]

[0107] In the formula, Q t,s The energy stored in the energy storage device at time t; Q s,max This represents the maximum storage capacity of the energy storage device.

[0108] During the real-time operation phase, the above-mentioned optimization model is used to make flexible unified reserves, and the remaining deviation is centrally balanced to ensure the real-time power balance of the power system.

[0109] 4. During the power delivery process, when renewable energy entities face power supply shortages or curtailment risks due to uncertainties in power generation, the flexibility provider adjusts unit output to compensate for deviations incurred by the renewable energy entity during real-time delivery. In selecting flexibility allocation options, priority is given to using the flexibility reserves independently coordinated by the renewable energy entity for balancing. If the independently coordinated flexibility reserves are insufficient to cover the renewable energy deviation, the unified flexibility reserve service is used to balance the remaining deviation.

[0110] 5. After the real-time power delivery, an imbalance settlement will be conducted based on the availability of flexible resources.

[0111] The method proposed in this invention explores the synergistic and complementary relationship between renewable energy sources and flexible energy sources, encouraging flexible energy sources to balance renewable energy deviations using their own adjustment capabilities before real-time operation. This solves the problem of surged real-time balancing pressure caused by the uncertainty of high-proportion renewable energy sources. Furthermore, the proposed flexibility incentive method is incorporated into the inter-provincial power transmission model, constructing a joint optimization model of day-ahead power and flexibility for renewable energy across provinces and regions, achieving coordinated and optimized operation of inter-provincial power transmission and flexibility reserves.

Claims

1. A flexible incentive method for ensuring real-time balance of a power system, characterized by, Includes the following steps: Step 1: One week before real-time operation, the renewable energy entities and the flexible energy entities independently carry out flexible reserves to balance the expected renewable energy deviation in advance. When the renewable energy entities face the risk of insufficient power supply or curtailment due to prediction deviation, the flexible energy entities use the reserved adjustment capacity to balance the renewable energy output deviation. Step 2: In the first 30 minutes of real-time operation, calculate the remaining deviation based on the actual system deviation and the flexibility reserve of autonomous coordination, and use the unified flexibility reserve to centrally balance the remaining deviation. Step 3: Construct a day-ahead power-flexibility joint optimization model for new energy sources across provinces and regions to achieve coordinated and optimized operation of inter-provincial power transmission and flexibility reserves; The joint optimization model for energy and flexibility in step 3 includes: Objective function: ； In the formula, and These represent the model's total energy and flexibility, respectively. and These refer to the electrical energy and energy coefficient of the main source of new energy; and These refer to the main electrical energy of thermal power plants and their energy coefficients; and These refer to adjusting the flexibility of the main body of thermal power plants and their flexibility coefficients. and These refer to the reduction of flexibility of the main body of thermal power plants and their flexibility coefficients; and These refer to adjusting the flexibility of the energy storage entity and its flexibility coefficient. and These refer to adjusting the flexibility of the energy storage entity and its flexibility coefficient. Step 4: Conduct power handover; Step 5: After the real-time power delivery, perform imbalance settlement based on the availability of flexible resources.

2. The flexible incentive method for ensuring real-time balance of the power system according to claim 1, characterized in that, The joint optimization model for energy and flexibility in step 3 also includes: Constraints: Power balance constraints ； In the formula, To meet the needs of inter-provincial power transmission, Transmission loss due to inter-provincial communication lines; Inter-provincial channel transmission capacity constraints ； In the formula, This represents the maximum transmittable capacity of the inter-provincial transmission channel. Inter-provincial renewable energy transmission ratio constraints ； In the formula, The minimum proportion of new energy transmission required for inter-provincial transmission channels; Flexibility Balance Constraints ； In the formula, and These refer to the flexibility of autonomous and coordinated upward and downward adjustments; and These refer to the flexibility of adjusting unified reserves both upwards and downwards; and These refer to the flexibility requirements for inter-provincial adjustments, both upward and downward. Renewable energy output constraints ； In the formula, This is the upper limit for inter-provincial power transmission, which is mainly driven by new energy sources. Power generation capacity constraints ； In the formula, This is the lower limit of the generating capacity of thermal power units; Apply for inter-provincial power transmission limits for thermal power plants; Flexibility and capacity constraints ； In the formula, This is the upper limit of the generating capacity of thermal power units; Thermal power plant ramping constraints ； In the formula, and These are the upper limits of the uphill and downhill ramp rates for thermal power units, respectively. Charge and discharge power constraints ； In the formula, and These are the 0 and 1 variables representing the charging and discharging states of the energy storage device, respectively. This refers to the upper limit of the charging and discharging power of energy storage devices. To improve the charging and discharging efficiency of energy storage devices; Charge and discharge capacity constraints ； In the formula, The energy stored in the energy storage device at time t; This represents the maximum storage capacity of the energy storage device.

3. The flexible incentive method for ensuring real-time balance of the power system according to claim 1, characterized in that, Step 4 specifically includes: during the power delivery process, when the new energy entity faces insufficient power supply or the risk of power curtailment due to the uncertainty of power generation, the flexibility entity makes up for the deviation generated by the new energy entity during the real-time delivery process; in terms of flexibility call selection, priority is given to calling the flexibility of the new energy entity through self-coordinated reserve to balance; if the self-coordinated flexibility reserve is insufficient to cover the new energy deviation, the unified reserve flexibility service is called to balance the remaining deviation.

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