A method and system for coordinated frequency regulation of thermal storage based on state of charge

Abstract

The application discloses a kind of based on the state of charge of fire storage collaborative frequency control method and system, comprising: if the SOC value of energy storage system is less than optimal value, reduce the discharge power upper limit of energy storage system, increase the output target value of thermal power unit;The charging power upper limit of energy storage system is adjusted to maximum;If the SOC value of energy storage system is greater than optimal value, the discharge power upper limit of energy storage system is adjusted to maximum, reduce the charging power upper limit of energy storage system;Reduce the output target value of thermal power unit;If the SOC value of energy storage system is equal to optimal value, the discharge power upper limit of energy storage system is adjusted to maximum, and charging power upper limit is adjusted to maximum;Energy storage system output target power value cannot be greater than the charging power upper limit or discharge power upper limit corresponding to the corresponding SOC value of energy storage system.By thus, through the present application, the overall efficiency of frequency modulation can be improved.

Description

Technical Field

[0001] This application relates to the field of power grid frequency regulation control technology, and in particular to a thermal power and energy storage coordinated frequency regulation control method and system based on state of charge. Background Technology

[0002] With the large-scale integration of new energy sources and the increasing complexity of power load dynamics, the requirements for the response speed and accuracy of power system frequency regulation have significantly increased. Secondary frequency regulation (automatic generation control), as a core component in maintaining grid frequency stability, needs to quickly balance the deviation between power generation and consumption.

[0003] Traditional thermal power units, limited by the mechanical inertia of the boiler-turbine system and the hysteresis of regulation, typically have a ramp rate of only 1%-2% of rated power per minute, making it difficult to adapt to the frequent power fluctuations caused by the high proportion of renewable energy grid connection. Although thermal power plants participate in frequency regulation by reserving spinning reserve capacity, their response delay (usually >30 seconds) can easily lead to frequency overshoot, exacerbating the risk of control loop oscillation.

[0004] Electrochemical energy storage systems (such as lithium-ion batteries) have become an effective means to improve the dynamic performance of secondary frequency regulation due to their millisecond-level response speed (<500ms) and precise power point tracking capability. However, electrochemical energy storage systems are limited by capacity decay, cost constraints, and continuous discharge duration (usually <15 minutes), making it difficult for them to independently undertake long-term frequency regulation tasks. This leads to a decrease in the frequency regulation performance index (Kp value) under long-term frequency regulation conditions.

[0005] Therefore, the current market uses hybrid energy storage, specifically battery energy storage assisting thermal power units in frequency regulation, which can improve the frequency regulation performance of thermal power units. However, existing regulation strategies are implemented in the following ways:

[0006] 1) Decoupling of energy storage system from thermal power unit control;

[0007] In existing thermal power and energy storage joint frequency regulation schemes, thermal power units only control their output based on their own relevant conditions and the frequency regulation target value during secondary frequency regulation, without referring to the SOC and other conditions of the energy storage system. This decoupled control method prevents the thermal power units and energy storage system from coordinating and optimizing, thus reducing the overall efficiency of frequency regulation.

[0008] 2) SOC static threshold setting;

[0009] Existing solutions often employ fixed SOC safety ranges, meaning that within these ranges, the energy storage system outputs power according to a pre-set algorithm without dynamically adjusting based on real-time frequency regulation requirements. This lack of consideration for real-time frequency regulation leads to insufficient system endurance. Specifically, if the overall SOC of the energy storage system is too high or too low, it will exit frequency regulation; energy storage units with excessively high or low SOCs will exit frequency regulation due to protection mechanisms, leaving insufficient remaining usable capacity, resulting in decreased overall system frequency regulation accuracy and endurance. For example, after a continuous ramp-up following an AGC command, if the energy storage system's SOC reaches the lower limit of the safety range, it cannot continue participating in frequency regulation, impacting frequency regulation benefits.

[0010] Due to these issues, existing control strategies do not consider the assessment process during AGC response. Therefore, during frequency regulation of the battery-assisted generating unit, unnecessary charging and discharging can lead to wasted electricity. While the battery storage system improves the frequency regulation performance of the thermal power unit to some extent, this improvement has not achieved the expected results, leaving considerable room for further improvement and reducing frequency regulation efficiency and economy. Summary of the Invention

[0011] Based on this, and to address the aforementioned technical problems, a method and system for coordinated frequency regulation control of thermal power and energy storage based on state of charge is provided to improve frequency regulation efficiency and economy.

[0012] Firstly, a method for coordinated frequency regulation control of thermal power and energy storage based on state of charge, the method comprising:

[0013] The system receives the total target value of the joint frequency regulation command for thermal power generation and the SOC value of the energy storage system, and determines the range in which the energy storage system is located based on the SOC value of the energy storage system; the total target value of the joint frequency regulation command for thermal power generation is used as the initial output target value of the thermal power unit.

[0014] If the SOC value of the energy storage system is less than the optimal value but greater than the safety lower limit of the energy storage system, then the upper limit of the discharge power of the energy storage system is reduced according to the first preset formula, and the upper limit of the charging power of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is less than the safety lower limit of the energy storage system, then the upper limit of the discharge power of the energy storage system is set to 0, and the upper limit of the charging power of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is less than the optimal value, then the current output target value of the thermal power unit is increased.

[0015] If the SOC value of the energy storage system is greater than the optimal value but less than the safety upper limit of the energy storage system, then the discharge power upper limit of the energy storage system is adjusted to the maximum, and the charging power upper limit of the energy storage system is reduced according to the second preset formula; the output target value of the thermal power unit is reduced according to a preset ratio; if the SOC value of the energy storage system is greater than the safety upper limit of the energy storage system, then the charging power upper limit of the energy storage system is set to 0, and the discharge power upper limit of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is greater than the optimal value, the current output target value upper limit of the thermal power unit is reduced.

[0016] If the SOC value of the energy storage system is equal to the optimal value, then the upper limit of the discharge power of the energy storage system is adjusted to the maximum, and the upper limit of the charging power is adjusted to the maximum; the initial output target value of the thermal power unit is taken as the current output target value of the thermal power unit.

[0017] The target output power value of the energy storage system is obtained based on the total target value of the combined thermal power and energy storage frequency regulation command and the actual current output power value of the thermal power unit. The target output power value of the energy storage system is either the discharge power or the charging power. The target output power value of the energy storage system shall not exceed the upper limit of the charging power or the upper limit of the discharge power corresponding to the SOC value of the energy storage system. The energy storage system outputs power according to the target output power value of the energy storage system to perform AGC frequency regulation.

[0018] Optionally, in the above scheme, the method further includes: generating a charging / discharging power allocation instruction for each energy storage unit based on the total discharge power value and the upper limit of charging power of the energy storage system, and simultaneously combining the SOC information of each energy storage unit in the energy storage system, according to the following formula:

[0019]

[0020] In the formula, P i The power command is output for the i-th energy storage unit, with negative for charging and positive for discharging; P ref This represents the total discharge power of the energy storage system; charging is negative, and discharging is positive. SOC (State of Charge) i Let SOC be the SOC of the i-th energy storage unit; k is the SOC deviation adjustment coefficient, which can be adjusted according to actual needs to maintain the balance rate.

[0021] Optionally, in the above scheme, the method further includes: when the total target value of the combined fire and energy storage frequency regulation command remains unchanged for a long time, or when the combined fire and energy storage frequency regulation period is terminated, if the difference between the SOC information of the energy storage unit and the optimal value is within a certain range, then charging and discharging are performed according to the set power.

[0022] Optionally, in the above scheme, the first preset formula is:

[0023]

[0024] Among them, P ref This is the total output power command for the energy storage system; charging is negative, discharging is positive; P max This parameter represents the maximum allowable output power of the energy storage system; charging is negative, discharging is positive. SOC is the real-time value of the energy storage system. opt The optimal value for the energy storage system; SOC min The lower limit of safety for energy storage systems; SOC max is the upper limit of safety for the energy storage system; n is the exponential correction factor.

[0025] Optionally, in the above scheme, the second preset formula is:

[0026]

[0027] Among them, P ref This is the total output power command for the energy storage system; charging is negative, discharging is positive; P max This parameter represents the maximum allowable output power of the energy storage system; charging is negative, discharging is positive. SOC is the real-time value of the energy storage system. opt The optimal SOC value for the energy storage system; SOC min The lower limit of safety for energy storage systems; SOC max is the upper limit of safety for the energy storage system; n is the exponential correction factor.

[0028] In the above scheme, optionally, the optimal value is 50% of the total SOC capacity of the energy storage system; the lower limit of the safety of the energy storage system includes 30%-0% of the total SOC capacity of the energy storage system; and the upper limit of the safety of the energy storage system includes 70%-100% of the total SOC capacity of the energy storage system.

[0029] Optionally, in the above scheme, increasing the current output target value of the thermal power unit includes: adding the initial output target value of the thermal power unit to the maximum design power of the energy storage system to obtain the current output target value of the thermal power unit;

[0030] The reduction of the current output target value of the thermal power unit includes: subtracting the maximum design power of the energy storage system from the initial output target value of the thermal power unit to obtain the current output target value of the thermal power unit.

[0031] Secondly, a thermal power and energy storage coordinated frequency regulation control system based on dynamic state of charge optimization, the system comprising:

[0032] Data receiving and judgment module: used to receive the total target value of the joint frequency regulation command of thermal power and energy storage, and to receive the SOC value of the energy storage system, and to determine the range in which the energy storage system is located based on the SOC value of the energy storage system; and to use the total target value of the joint frequency regulation command of thermal power and energy storage as the initial output target value of the thermal power unit;

[0033] The adjustment mechanism calculation module is used to: if the SOC value of the energy storage system is less than the optimal value but greater than the safe lower limit of the SOC value of the energy storage system, reduce the upper limit of the discharge power of the energy storage system according to a first preset formula and adjust the upper limit of the charging power of the energy storage system to the maximum; if the SOC value of the energy storage system is less than the safe lower limit of the SOC value of the energy storage system, set the upper limit of the discharge power of the energy storage system to 0 and adjust the upper limit of the charging power of the energy storage system to the maximum; if the SOC value of the energy storage system is less than the optimal value, add the maximum design power of the energy storage system to the initial target value of the thermal power unit output to obtain the current target value of the thermal power unit output; if the SOC value of the energy storage system is greater than the optimal value but less than the safe upper limit of the energy storage system, reduce the upper limit of the discharge power of the energy storage system according to a first preset formula and adjust the upper limit of the charging power of the energy storage system to the maximum; if the SOC value of the energy storage system is greater than the optimal value but less than the safe upper limit of the energy storage system, reduce the upper limit of the discharge power of the energy storage system to the maximum; if the SOC value of the energy storage system is less than the optimal value but greater than the safe lower limit of the SOC value of the energy storage system, adjust the upper limit of the discharge power of the energy storage system to the maximum; if the SOC value of the energy storage system is greater than the optimal value but less than the safe upper limit ... The power limit is adjusted to the maximum, and the charging power limit of the energy storage system is reduced according to the second preset formula; the output target value of the thermal power unit is reduced according to a preset ratio; if the SOC value of the energy storage system is greater than the safe SOC limit of the energy storage system, the charging power limit of the energy storage system is set to 0, and the discharge power limit of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is greater than the optimal value, the initial output target value of the thermal power unit is added to the maximum design power of the energy storage system to obtain the current output target value of the thermal power unit; if the SOC value of the energy storage system is equal to the optimal value, the discharge power limit of the energy storage system is adjusted to the maximum; the initial output target value of the thermal power unit is used as the current output target value of the thermal power unit.

[0034] The energy storage system's discharge output target value calculation module is used to calculate the energy storage system's output target power value based on the total target value of the combined thermal and energy storage frequency regulation command and the actual current output power value of the thermal power unit. The energy storage system's output target power value is either discharge power or charging power. The energy storage system's output target power value must not exceed the upper limit of charging power or the upper limit of discharge power corresponding to the energy storage system's SOC value. The energy storage system outputs power based on the energy storage system's output target power value to perform AGC frequency regulation.

[0035] Thirdly, a computer device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the steps of the state-of-charge-based coordinated frequency modulation control method for fire and energy storage as described in the first aspect.

[0036] Fourthly, a computer program product includes a computer program / instructions that, when executed by a processor, implement the steps of the state-of-charge-based coordinated frequency modulation control method for fire and energy storage as described in the first aspect.

[0037] This application has at least the following beneficial effects:

[0038] This application addresses the issue of the energy storage system's SOC (State of Charge) being lower than its optimal value. First, it lowers the upper limit of the energy storage system's discharge power according to a first preset formula, while maximizing the upper limit of its charging power. Second, it increases the target output value of the thermal power unit according to a preset ratio. Third, when the energy storage system's SOC is greater than its optimal value, it maximizes the upper limit of the energy storage system's discharge power and lowers the upper limit of its charging power according to a second preset formula. Finally, it reduces the target output value of the thermal power unit according to a preset ratio. This ensures that the energy storage system's SOC capacity is around its optimal value, avoiding excessively high or low values ​​and minimizing the risk of it being excluded from frequency regulation. Furthermore, the interaction between the target output value of the thermal power unit and the SOC of the energy storage system allows for coordinated optimization between the thermal power unit and the energy storage system, improving the overall efficiency of frequency regulation and preventing unnecessary charging and discharging that could lead to energy waste, thus enhancing economic efficiency.

[0039] Based on the SOC information of each energy storage unit in the energy storage system, the total discharge power value and the upper limit of the charging power of the energy storage system are allocated, so that the SOC value of each storage unit is kept as close as possible to the optimal value, and will not be at a high or low level for a long time, so as not to affect the battery life and improve the frequency regulation range. Attached Figure Description

[0040] Figure 1 A flowchart of a thermal power and energy storage coordinated frequency modulation control method based on state of charge is provided for one embodiment of this application;

[0041] Figure 2 This is a diagram illustrating the control process of a thermal power unit during a single AGC frequency regulation process, as provided in one embodiment of this application. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0043] In one embodiment, such as Figure 1 As shown, a thermal power-storage coordinated frequency regulation control method based on state of charge is provided, including the following steps:

[0044] Step S1: Receive the total target value of the joint frequency regulation command for thermal power and energy storage, and receive the SOC value of the energy storage system, and determine the range in which the energy storage system is located based on the SOC value of the energy storage system; use the total target value of the joint frequency regulation command for thermal power and energy storage as the initial output target value of the thermal power unit;

[0045] Step S2: If the SOC value of the energy storage system is less than the optimal value but greater than the safety lower limit of the energy storage system, then the upper limit of the discharge power of the energy storage system is reduced according to the first preset formula, and the upper limit of the charging power of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is less than the safety lower limit of the energy storage system, then the upper limit of the discharge power of the energy storage system is set to 0, and the upper limit of the charging power of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is less than the optimal value, then the current output target value of the thermal power unit is increased.

[0046] Step S3: If the SOC value of the energy storage system is greater than the optimal value but less than the safety upper limit of the energy storage system, then the discharge power upper limit of the energy storage system is adjusted to the maximum, and the charging power upper limit of the energy storage system is reduced according to the second preset formula; the output target value of the thermal power unit is reduced according to the preset ratio; if the SOC value of the energy storage system is greater than the safety upper limit of the energy storage system, then the charging power upper limit of the energy storage system is set to 0, and the discharge power upper limit of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is greater than the optimal value, the current output target value upper limit of the thermal power unit is reduced.

[0047] Step S4: If the SOC value of the energy storage system is equal to the optimal value, then the upper limit of the discharge power of the energy storage system is adjusted to the maximum, and the upper limit of the charging power is adjusted to the maximum; the initial output target value of the thermal power unit is taken as the current output target value of the thermal power unit.

[0048] Step S5: Based on the total target value of the combined thermal and energy storage frequency regulation command and the actual current output power value of the thermal power unit, the target output power value of the energy storage system is obtained. The target output power value of the energy storage system is either discharge power or charging power. The target output power value of the energy storage system shall not exceed the upper limit of charging power or the upper limit of discharge power corresponding to the SOC value of the energy storage system. The energy storage system outputs power according to the target output power value of the energy storage system to perform AGC frequency regulation.

[0049] In this embodiment, the upper limit of charge and discharge power is adjusted according to the SOC active self-recovery algorithm. Specifically, this includes:

[0050] During frequency regulation, the output of the energy storage system is dynamically allocated based on the system's State of Charge (SOC).

[0051]

[0052] Among them, P ref This is the total output power command for the energy storage system; charging is negative, discharging is positive; P max This parameter represents the maximum allowable output power of the energy storage system; charging is negative, discharging is positive. SOC is the real-time value of the energy storage system. opt The optimal value for C in the energy storage system; SOCmin The lower limit of safety for energy storage systems; SOC max is the upper limit of safety for the energy storage system; n is the exponential correction factor.

[0053] 1) When the SOC of the energy storage system is lower than the SOC opt When SOC is greater than min Then, the upper limit of the discharge power of the energy storage system will be reduced according to the above formula, while the upper limit of the charging power will be adjusted to the maximum. When the SOC of the energy storage system is lower than the SOC min When this occurs, the upper limit of the energy storage system's discharge power is set to 0, meaning discharge is prohibited.

[0054] 2) When the SOC of the energy storage system is higher than the SOC opt But smaller than SOC max When the SOC of the energy storage system is higher than the SOC of the energy storage system, the upper limit of the charging power will be reduced according to the above formula, while the upper limit of the discharging power will be adjusted to the maximum. max When this occurs, the upper limit of the energy storage system's charging power is set to 0, meaning charging is prohibited.

[0055] Meanwhile, the output target value of thermal power units follows the thermal-storage coordinated SOC recovery strategy: specifically:

[0056] During frequency regulation, the target output value of the thermal power unit is dynamically changed according to the SOC of the energy storage system:

[0057] 1) When the SOC value of the energy storage system is lower than the optimal value (e.g., 50%):

[0058] Increase the target output value of thermal power units by a certain proportion so that after the power of thermal power units reaches the AGC command value (i.e., Figure 2 During the T4-T5 phase, the system continues to output power, allowing the energy storage system to maintain the combined power near the AGC command value through charging.

[0059] 2) When the SOC value of the energy storage system is higher than the optimal value (e.g., 50%):

[0060] The output target value of thermal power units will be reduced by a certain percentage so that the power of thermal power units can be reduced even if the AGC command value is not reached (i.e., Figure 2 During the T4 to T5 phases, the combined power remains constant, and the energy storage system can maintain the combined power near the AGC command value by discharging.

[0061] Increasing the current target output value of the thermal power unit includes: adding the initial target output value of the thermal power unit to the maximum design power of the energy storage system to obtain the current target output value of the thermal power unit;

[0062] Reducing the current output target value of the thermal power unit includes: subtracting the maximum design power of the energy storage system from the initial output target value of the thermal power unit to obtain the current output target value of the thermal power unit.

[0063] Adjusting the charging power limit to the maximum or discharging power limit to the maximum mentioned above refers to adjusting it to the maximum value of the design power range.

[0064] When the energy storage system is charging, it absorbs energy from the grid. This allows the system to replenish its power during the charging process, increasing its State of Charge (SOC) to nearly 50%.

[0065] In the aforementioned state-of-charge (SOC)-based thermal power-storage coordinated frequency regulation control method, when the SOC of the energy storage system is less than the optimal value, the upper limit of the discharge power of the energy storage system is reduced according to a first preset formula, while the upper limit of the charging power of the energy storage system is adjusted to the maximum; the target output value of the thermal power unit is increased according to a preset ratio. When the SOC of the energy storage system is greater than the optimal value, the upper limit of the discharge power of the energy storage system is adjusted to the maximum, and the upper limit of the charging power of the energy storage system is reduced according to a second preset formula; the target output value of the thermal power unit is reduced according to a preset ratio. This ensures that the SOC capacity of the energy storage system is around the optimal value, neither too high nor too low, and is less likely to result in frequency regulation withdrawal. Simultaneously, the influence between the target output value of the thermal power unit and the SOC of the energy storage system enables coordinated optimization between the thermal power unit and the energy storage system, improving the overall efficiency of frequency regulation and preventing unnecessary charging and discharging that would lead to power waste, thus improving economic efficiency.

[0066] Existing solutions often distribute the total frequency regulation power command evenly among all energy storage units, without considering the State of Charge (SOC) differences between units, resulting in an imbalance in SOC. Consequently, due to differences in capacity or historical charge / discharge depths, some units maintain a consistently high or low SOC, accelerating battery aging. Irregular deep charge / discharge cycles severely impact battery lifespan and degrade battery chemical performance, further contributing to short frequency regulation range.

[0067] In one embodiment, based on the total discharge power and charging power limit of the energy storage system, and in conjunction with the SOC information of each energy storage unit in the energy storage system, a charging / discharging power allocation instruction for each energy storage unit is generated according to the following formula:

[0068]

[0069] In the formula, P i The power command is output for the i-th energy storage unit, with negative for charging and positive for discharging; P ref This represents the total discharge power of the energy storage system; charging is negative, and discharging is positive. SOC (State of Charge) i Let SOC be the SOC of the i-th energy storage unit; k is the SOC deviation adjustment coefficient, which can be adjusted according to actual needs to maintain the balance rate.

[0070] In this embodiment, the weight of each energy storage unit in frequency regulation output is dynamically adjusted according to the SOC deviation. The energy storage unit with a SOC closer to the average value is assigned a lower output weight to maintain the SOC balance of each energy storage unit in the energy storage system.

[0071] In one embodiment, the method further includes: when the total target value of the combined thermal and energy storage frequency regulation command remains unchanged for a long time, or when the combined thermal and energy storage frequency regulation is suspended, if the difference between the SOC information of the energy storage unit and the optimal value is within a certain range, then charging and discharging are performed according to the set power.

[0072] In this embodiment, 1) if the AGC command remains unchanged for a long time, or during the period of exiting AGC frequency regulation, the system is charged and discharged at a certain power according to the optimal SOC deviation value to maintain the optimal SOC of the energy storage system.

[0073] 2) When the AGC command exceeds the output range of the thermal power unit, the system charges and discharges at a certain power according to the optimal SOC deviation value to maintain the optimal SOC of the energy storage system.

[0074] In one embodiment, the optimal value is 50% of the total SOC capacity of the energy storage system; the lower safety limit of the energy storage system includes 30%-0% of the total SOC capacity of the energy storage system; and the upper safety limit of the energy storage system includes 70%-100% of the total SOC capacity of the energy storage system.

[0075] In this embodiment, the lower and upper safety limits of the energy storage system can be adjusted according to the actual situation.

[0076] In one embodiment, such as Figure 2 As shown, this is a typical AGC frequency regulation control process for a thermal power unit within the grid. In the figure, the blue line represents the AGC command value, and the red line represents the actual power value of the thermal power unit. A typical AGC frequency regulation process can be divided into the following three stages:

[0077] (1) Response phase:

[0078] The time interval is from T0 to T1.

[0079] At time T0, the thermal power unit's AGC control program issues a target power value command of P2 to the unit, and the unit will cross the regulation dead zone at time T1.

[0080] The energy storage system determines the output direction based on the difference between the AGC command and the current unit power, and tries to get the combined power out of the regulation dead zone as soon as possible before time T1.

[0081] (2) Climbing phase:

[0082] The time interval is from T1 to T4.

[0083] During this period, the thermal power units increased their output according to a certain process. Simultaneously, the energy storage system, based on the AGC command and the difference between the current unit power, quickly increased the combined power output to the P2 target value.

[0084] (3) Stable phase:

[0085] The time interval is from T4 to T5.

[0086] During this period, the thermal power unit then oscillated slightly around the P2 target value and stabilized near it. Simultaneously, the energy storage system, based on the AGC command and the current unit power difference, minimized the error between the combined power output and the P2 target value.

[0087] This application has the following advantages compared to existing fire-storage coordinated control strategies:

[0088] 1) Improve battery life:

[0089] Energy storage systems utilize SOC self-recovery algorithms to maintain the system's SOC at around 50%, ensuring sufficient margin for secondary frequency regulation needs during both charging and discharging. This results in longer frequency regulation range and higher frequency regulation benefits.

[0090] 2) Improve performance indicators:

[0091] Some energy storage units may be unable to participate in frequency regulation control due to excessively high or low State of Charge (SOC), thus affecting the output capacity of the energy storage system and impacting frequency regulation performance. By using a dynamic SOC balancing algorithm, the SOC of each unit can be effectively maintained at the same level, thereby improving the frequency regulation performance index (Kp).

[0092] 3) Extend battery life:

[0093] Energy storage systems can maintain the system's State of Charge (SOC) at around 50% through algorithms that enable SOC self-recovery. SOC is a crucial factor affecting the lifespan of electrochemical batteries. Statistics show that lithium iron phosphate batteries stored at 100% or 0% SOC experience an annual capacity loss of approximately 3-5%, while those stored at 50% SOC experience an annual capacity loss of approximately 1-2%.

[0094] In one embodiment, a thermal power and energy storage coordinated frequency regulation control system based on dynamic state of charge optimization includes:

[0095] Data receiving and judgment module: used to receive the total target value of the joint frequency regulation command of thermal power and energy storage, and to receive the SOC value of the energy storage system, and to determine the range in which the energy storage system is located based on the SOC value of the energy storage system; and to use the total target value of the joint frequency regulation command of thermal power and energy storage as the initial output target value of the thermal power unit;

[0096] The adjustment mechanism calculation module is used to: if the SOC value of the energy storage system is less than the optimal value but greater than the safe lower limit of the SOC value of the energy storage system, reduce the upper limit of the discharge power of the energy storage system according to a first preset formula and adjust the upper limit of the charging power of the energy storage system to the maximum; if the SOC value of the energy storage system is less than the safe lower limit of the SOC value of the energy storage system, set the upper limit of the discharge power of the energy storage system to 0 and adjust the upper limit of the charging power of the energy storage system to the maximum; if the SOC value of the energy storage system is less than the optimal value, add the maximum design power of the energy storage system to the initial target value of the thermal power unit output to obtain the current target value of the thermal power unit output; if the SOC value of the energy storage system is greater than the optimal value but less than the safe upper limit of the energy storage system, reduce the upper limit of the discharge power of the energy storage system according to a first preset formula and adjust the upper limit of the charging power of the energy storage system to the maximum; if the SOC value of the energy storage system is greater than the optimal value but less than the safe upper limit of the energy storage system, reduce the upper limit of the discharge power of the energy storage system to the maximum; if the SOC value of the energy storage system is less than the optimal value but greater than the safe lower limit of the SOC value of the energy storage system, adjust the upper limit of the discharge power of the energy storage system to the maximum; if the SOC value of the energy storage system is greater than the optimal value but less than the safe upper limit ... The power limit is adjusted to the maximum, and the charging power limit of the energy storage system is reduced according to the second preset formula; the output target value of the thermal power unit is reduced according to a preset ratio; if the SOC value of the energy storage system is greater than the safe SOC limit of the energy storage system, the charging power limit of the energy storage system is set to 0, and the discharge power limit of the energy storage system is adjusted to the maximum; if the SOC value of the energy storage system is greater than the optimal value, the initial output target value of the thermal power unit is added to the maximum design power of the energy storage system to obtain the current output target value of the thermal power unit; if the SOC value of the energy storage system is equal to the optimal value, the discharge power limit of the energy storage system is adjusted to the maximum; the initial output target value of the thermal power unit is used as the current output target value of the thermal power unit.

[0097] The energy storage system's discharge output target value calculation module is used to calculate the energy storage system's output target power value based on the total target value of the combined thermal and energy storage frequency regulation command and the actual current output power value of the thermal power unit. The energy storage system's output target power value is either discharge power or charging power. The energy storage system's output target power value must not exceed the upper limit of charging power or the upper limit of discharge power corresponding to the energy storage system's SOC value. The energy storage system outputs power based on the energy storage system's output target power value to perform AGC frequency regulation.

[0098] Specific limitations regarding the thermal power-storage coordinated frequency regulation control system based on dynamic state of charge optimization can be found in the above description of the limitations of the thermal power-storage coordinated frequency regulation control method based on dynamic state of charge optimization, and will not be repeated here. Each module in the aforementioned thermal power-storage coordinated frequency regulation control system based on dynamic state of charge optimization can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the corresponding operations of each module.

[0099] In one embodiment, a computer device is provided, which may be a server. The computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it implements the aforementioned method for coordinated frequency regulation control of thermal power and energy storage based on dynamic optimization of state of charge.

[0100] In one embodiment, a computer program product is also provided, including a computer program / instructions that, when executed by a processor, relate to all or part of the processes in the methods of the above embodiments.

[0101] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, or optical storage, etc. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM), etc.

[0102] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0103] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A method for coordinated frequency regulation control of thermal power and energy storage based on state of charge, characterized in that, The method includes: Receive the total target value of the joint frequency regulation command for thermal power and energy storage, and receive the energy storage system Value, and according to the energy storage system The value determines the interval where the energy storage system is located; the total target value of the combined thermal and energy storage frequency regulation command is used as the initial output target value of the thermal power unit; If the energy storage system If the value is less than the optimal value but greater than the safety lower limit of the energy storage system, then the upper limit of the discharge power of the energy storage system is reduced according to the first preset formula, and the upper limit of the charging power of the energy storage system is adjusted to the maximum; if the energy storage system If the value is less than the safety lower limit of the energy storage system, then the upper limit of the discharge power of the energy storage system is set to 0, and the upper limit of the charging power of the energy storage system is adjusted to the maximum; if the energy storage system If the value is less than the optimal value, increase the current output target value of the thermal power unit; the first preset formula is: ， in, This is the total output power command for the energy storage system; charging is negative and discharging is positive. This is the maximum allowable output power parameter for the energy storage system; charging is negative and discharging is positive. For energy storage systems Real-time value; This is the optimal value for the energy storage system; Safety lower limit of energy storage systems; The upper limit of safety for the energy storage system; n is the exponential correction factor; If the energy storage system If the value is greater than the optimal value but less than the safety upper limit of the energy storage system, then the discharge power upper limit of the energy storage system is adjusted to the maximum, and the charging power upper limit of the energy storage system is reduced according to the second preset formula; the output target value of the thermal power unit is reduced according to a preset ratio; if the energy storage system If the value is greater than the safety limit of the energy storage system, then the charging power limit of the energy storage system is set to 0, and the discharging power limit of the energy storage system is adjusted to the maximum; if the energy storage system If the value is greater than the optimal value, lower the upper limit of the current output target value of the thermal power unit; The second preset formula is: ， in, This is the total output power command for the energy storage system; charging is negative and discharging is positive. This is the maximum allowable output power parameter for the energy storage system; charging is negative and discharging is positive. For energy storage systems Real-time value; This is the optimal value for the energy storage system; This represents the lower safety limit for energy storage systems. The upper limit of safety for the energy storage system; n is the exponential correction factor; If the energy storage system If the value equals the optimal value, then the upper limit of the discharge power of the energy storage system is adjusted to the maximum, and the upper limit of the charging power is adjusted to the maximum; the initial output target value of the thermal power unit is taken as the current output target value of the thermal power unit. The target output power value of the energy storage system is obtained based on the total target value of the combined thermal power and energy storage frequency regulation command and the actual current output power value of the thermal power unit. The target output power value of the energy storage system is either the discharge power or the charging power, and the target output power value of the energy storage system must not exceed the corresponding value of the energy storage system. The value corresponds to the upper limit of charging power or the upper limit of discharging power; the energy storage system outputs power according to the target power value of the energy storage system to perform AGC frequency regulation.

2. The thermal energy storage coordinated frequency regulation control method based on state of charge as described in claim 1, characterized in that, The method further includes: based on the total discharge power value and the upper limit of the charging power of the energy storage system, and simultaneously combining the values ​​of each energy storage unit in the energy storage system. The information is used to generate charging and discharging power allocation instructions for each energy storage unit based on the following formula: ， In the formula, Output power command to the i-th energy storage unit, with negative for charging and positive for discharging; This represents the total discharge power of the energy storage system; charging is negative, and discharging is positive. For the i-th group of energy storage units ; for The deviation adjustment coefficient can be used to adjust the balancing rate according to actual needs.

3. The thermal energy storage coordinated frequency regulation control method based on state of charge as described in claim 2, characterized in that, The method further includes: when the total target value of the combined thermal and energy storage frequency regulation command remains unchanged for a long period of time, or when the combined thermal and energy storage frequency regulation is suspended, when the energy storage unit's If the difference between the information and the optimal value is within a certain range, then charging and discharging will be performed according to the set power.

4. The thermal energy storage coordinated frequency regulation control method based on state of charge as described in claim 1, characterized in that, The optimal value is the total value of the energy storage system. The energy storage system's safety lower limit includes 30%-0% of its total SOC capacity; the energy storage system's safety upper limit includes the total SOC capacity of the energy storage system. 70%-100% of the capacity.

5. The thermal energy storage coordinated frequency regulation control method based on state of charge as described in claim 1, characterized in that, The method of increasing the current output target value of the thermal power unit includes: adding the initial target value of the thermal power unit's output to the maximum design power of the energy storage system to obtain the current target value of the thermal power unit's output; The reduction of the current output target value of the thermal power unit includes: subtracting the maximum design power of the energy storage system from the initial output target value of the thermal power unit to obtain the current output target value of the thermal power unit.

6. A thermal-storage coordinated frequency regulation control system based on dynamic state of charge optimization, characterized in that, The system includes: Data receiving and judgment module: used to receive the total target value of the joint frequency regulation command for thermal power and energy storage, and to receive the SOC value of the energy storage system, and to judge the data according to the energy storage system. The value determines the interval where the energy storage system is located; the total target value of the combined thermal and energy storage frequency regulation command is used as the initial output target value of the thermal power unit; Regulation mechanism calculation module: used for the energy storage system If the value is less than the optimal value but greater than the SOC safety lower limit of the energy storage system, then the upper limit of the discharge power of the energy storage system is reduced according to the first preset formula, and the upper limit of the charging power of the energy storage system is adjusted to the maximum; if the energy storage system The value is less than that of the energy storage system If the safety lower limit is set, the upper limit of the discharge power of the energy storage system is set to 0, and the upper limit of the charging power of the energy storage system is adjusted to the maximum. If the SOC value of the energy storage system is less than the optimal value, the current target value of the thermal power unit's output is obtained by adding the maximum design power of the energy storage system to the initial target value of the thermal power unit's output. If the energy storage system... If the value is greater than the optimal value but less than the safety upper limit of the energy storage system, then the discharge power upper limit of the energy storage system is adjusted to the maximum, and the charging power upper limit of the energy storage system is reduced according to the second preset formula; the output target value of the thermal power unit is reduced according to a preset ratio; if the energy storage system The value is greater than that of the energy storage system If the safety limit is reached, then the charging power limit of the energy storage system is set to 0, and the discharging power limit of the energy storage system is adjusted to the maximum; if the energy storage system If the value is greater than the optimal value, the initial output target value of the thermal power unit is added to the maximum design power of the energy storage system to obtain the current output target value of the thermal power unit; if the energy storage system If the value equals the optimal value, then the upper limit of the discharge power of the energy storage system is adjusted to the maximum; the initial output target value of the thermal power unit is taken as the current output target value of the thermal power unit; the first preset formula is: ， in, This is the total output power command for the energy storage system; charging is negative and discharging is positive. This is the maximum allowable output power parameter for the energy storage system; charging is negative and discharging is positive. For energy storage systems Real-time value; This is the optimal value for the energy storage system; Safety lower limit of energy storage systems; The upper limit of safety for the energy storage system; n is the exponential correction factor; The second preset formula is: ， in, This is the total output power command for the energy storage system; charging is negative and discharging is positive. This is the maximum allowable output power parameter for the energy storage system; charging is negative and discharging is positive. For energy storage systems Real-time value; This is the optimal value for the energy storage system; This represents the lower safety limit for energy storage systems. The upper limit of safety for the energy storage system; n is the exponential correction factor; The energy storage system's discharge output target value calculation module is used to calculate the energy storage system's output target power value based on the total target value of the combined thermal and energy storage frequency regulation command and the actual current output power value of the thermal power unit. The energy storage system's output target power value is either discharge power or charging power, and the energy storage system's output target power value must not exceed the upper limit of charging power or discharge power corresponding to the energy storage system's SOC value. The energy storage system outputs power based on the energy storage system's output target power value to perform AGC frequency regulation.

7. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 5.

8. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, they implement the steps of the method according to any one of claims 1 to 5.

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