A fire storage combined frequency modulation method, device, medium and equipment

Abstract

The present disclosure relates to a kind of fire storage combined frequency modulation method, device, medium and equipment, method includes: receiving power grid frequency, determine the frequency deviation of power grid frequency relative to rated power grid frequency and the frequency variation rate of power grid frequency;When frequency deviation and frequency variation rate meet the trigger primary frequency modulation mode, the power instruction channel corresponding to automatic power generation control is set to the lockout state, in different time period, multiple energy storage devices are allocated frequency modulation power output task;When meeting the end condition of primary frequency modulation mode, the lockout state is released, to the reference power of automatic power generation control as the basis, based on real-time target power recovery, power instruction is issued to energy storage system and thermal power generating unit;With real-time target power as initial control point, update real-time target power based on the consumption progress of power buffer queue, generate energy storage output instruction and thermal power output instruction based on updated real-time target power, make the total output power of fire storage combined frequency modulation system track real-time target power.

Description

Technical Field

[0001] This disclosure relates to the field of power system frequency control technology, specifically to a method, apparatus, medium, and equipment for combined thermal and energy storage frequency regulation. Background Technology

[0002] As the proportion of new energy power generation in the power system continues to increase, the problem of grid frequency fluctuations is becoming increasingly prominent. The thermal power-storage combined frequency regulation system, which combines thermal power generating units with energy storage systems, utilizes the rapid response characteristics of energy storage devices to compensate for the hysteresis of mechanical inertia in thermal power units, and has become an important technical means to improve the frequency stability of the power grid.

[0003] Grid frequency regulation is divided into two levels: primary frequency regulation and Automatic Generation Control (AGC). Primary frequency regulation refers to the automatic and rapid response of energy storage systems and thermal power units based on frequency regulation characteristic coefficients when the grid frequency deviates from its rated value; the response time is typically within seconds. Automatic generation control refers to the dispatching system periodically issuing power regulation commands based on the grid operating status to eliminate steady-state frequency deviations; the regulation timescale is typically on the order of minutes.

[0004] In a combined thermal power and energy storage frequency regulation system, primary frequency regulation and automatic generation control are triggered by different control logics, exhibiting significant differences in control time scale and response characteristics. When the grid frequency changes drastically, commands from primary frequency regulation and automatic generation control may simultaneously act on the energy storage system. Without an effective coordination control mechanism, the commands from the two control modes may overlap or conflict at the energy storage system side, affecting the frequency regulation effect. Improving the coordinated control performance of primary frequency regulation and automatic generation control in a combined thermal power and energy storage frequency regulation system is a key technical problem that needs to be solved in the field of combined thermal power and energy storage frequency regulation. Summary of the Invention

[0005] To address the aforementioned technical problems, this disclosure provides a method, apparatus, medium, and equipment for combined thermal and energy storage frequency regulation, thereby resolving the technical issue of insufficient coordination between primary frequency regulation and automatic generation control in existing combined thermal and energy storage frequency regulation systems.

[0006] The first aspect of this disclosure provides a combined thermal power and energy storage frequency regulation method applied to an energy management system. The method includes: receiving the grid frequency; determining the frequency deviation of the grid frequency relative to the rated grid frequency and the frequency change rate of the grid frequency; when the frequency deviation and frequency change rate satisfy the conditions for triggering a primary frequency regulation mode, setting the power command channel corresponding to the automatic generation control to a locked state; storing the power deviation amount corresponding to the automatic generation control adjustment command received during the locked state into a power buffer queue according to the receiving time sequence; and allocating frequency regulation power output tasks to various energy storage devices at different time periods based on the response speed differences of various energy storage devices in the energy storage system; when the conditions for ending the primary frequency regulation mode are met, releasing the locked state; obtaining the real-time target power by superimposing the power deviation amount on the reference power corresponding to the automatic generation control; and resuming the issuance of power commands to the energy storage system and the thermal power generating unit based on the real-time target power; in the automatic generation control mode, using the real-time target power as the initial control point, updating the real-time target power based on the absorption progress of the power buffer queue; and generating and issuing energy storage output commands and thermal power output commands respectively based on the updated real-time target power, so that the total output power of the combined thermal power and energy storage frequency regulation system tracks the real-time target power.

[0007] Further, after determining the frequency deviation of the grid frequency relative to the rated grid frequency and the frequency change rate of the grid frequency, the process includes: when the absolute value of the frequency deviation is greater than or equal to a first deviation threshold, and the duration of the absolute value of the frequency deviation being greater than or equal to the first deviation threshold is greater than the dead zone duration; or when the absolute value of the frequency change rate is greater than or equal to a change rate threshold, and the absolute value of the frequency deviation is greater than or equal to a second deviation threshold; wherein the second deviation threshold is less than the first deviation threshold; and determining the current frequency regulation mode as a primary frequency regulation mode.

[0008] Furthermore, the power command channel corresponding to the automatic generation control is set to a locked state, and the power deviation corresponding to the automatic generation control adjustment command received during the locked state is stored in the power buffer queue according to the receiving time sequence. This includes: setting the power command channel to a locked state, causing the energy storage system to stop responding to the automatic generation control adjustment command; acquiring the automatic generation control adjustment command sent by the automatic generation control system at a preset sampling period, and parsing the automatic generation control adjustment command into a power deviation; storing the power deviation in the power buffer queue according to the time sequence; wherein, during the locked state, if the difference between the power command of the primary frequency regulation mode and the historical reference power of the automatic generation control adjustment exceeds the power limit of the energy storage system, the power over-limit protection is triggered.

[0009] Furthermore, based on the differences in response speed among various energy storage devices in the energy storage system, frequency regulation power output tasks are assigned to various energy storage devices at different time periods, including: in the initial stage of a single frequency regulation response, instructing the first energy storage device with a first response speed in the energy storage system to output the first frequency regulation power; in the continuous stage following the initial stage, instructing the second energy storage device with a second response speed in the energy storage system to output the second frequency regulation power, and instructing the first energy storage device to reduce the first frequency regulation power to a preset maintenance power at a preset derating rate; in the long-term stage following the continuous stage, instructing the thermal power generating unit to output frequency regulation power at a preset slow rate to coordinate with the second energy storage device.

[0010] Furthermore, the ratio of the first rated power corresponding to the first energy storage device to the sum of the first rated power and the second rated power corresponding to the second energy storage device is within a preset range; wherein, the energy capacity of the first energy storage device is less than that of the second energy storage device; when the state of charge of the first energy storage device is lower than the first lower limit of charge or higher than the first upper limit of charge, the first energy storage device is instructed to reduce its output power to less than the first frequency regulation power; or, when the state of charge of the second energy storage device is lower than the second lower limit of charge or higher than the second upper limit of charge, the output power of the second energy storage device is reduced to less than the second frequency regulation power; when the output power of the first energy storage device is less than the first frequency regulation power, or the output power of the second energy storage device is less than the second frequency regulation power, the total frequency regulation power deficit is calculated, and the thermal power generating unit is controlled to supplement the total frequency regulation power deficit at a preset slow adjustment rate.

[0011] Furthermore, when the conditions for ending the primary frequency regulation mode are met, the lockout state is released, and the real-time target power is obtained by superimposing the power deviation based on the reference power corresponding to the automatic generation control. Power commands are then issued to the energy storage system and thermal power generating units based on the real-time target power. This includes: releasing the lockout state of the automatic generation control mode after the end conditions have been continuously met for more than the recovery confirmation time; gradually retrieving the power deviation from the power buffer queue at a preset change rate as the upper limit, and superimposing the power deviation to the recovery reference power to obtain the current real-time target power of the automatic generation control; instructing the automatic generation control to resume issuing power commands to the energy storage system and thermal power generating units based on the real-time target power; and if the execution time for retrieving the power buffer queue exceeds a preset timeout threshold, the power buffer queue is cleared and the reference power of the automatic generation control is recalculated based on the current grid frequency deviation.

[0012] Furthermore, when the frequency regulation mode is the primary frequency regulation mode, the method also includes: calculating the primary frequency regulation total power command based on the deviation of the grid frequency from the rated frequency according to the preset frequency regulation characteristic coefficient; using the primary frequency regulation total power command as the basis for allocating the frequency regulation power output tasks of various energy storage devices, and instructing the energy storage system to output frequency regulation power according to the allocation result; when the available total power of the energy storage system is less than the primary frequency regulation total power command, the thermal power generating unit supplements the power deficit at a preset slow rate.

[0013] A second aspect of this disclosure provides a combined thermal and energy storage frequency regulation device, comprising: a receiving module configured to receive the grid frequency and determine the frequency deviation of the grid frequency relative to the rated grid frequency and the frequency change rate of the grid frequency; and an allocation module configured to, when the frequency deviation and frequency change rate satisfy the triggering of a primary frequency regulation mode, set the power command channel corresponding to the automatic generation control to a locked state, store the power deviation corresponding to the automatic generation control regulation command received during the locked state into a power buffer queue according to the receiving time sequence, and allocate frequency regulation to multiple energy storage devices at different time periods based on the response speed differences of multiple energy storage devices in the energy storage system. The power output task includes a recovery module, configured to release the lockout state when the primary frequency regulation mode termination condition is met, obtain the real-time target power by superimposing the power deviation based on the reference power corresponding to the automatic generation control, and issue power commands to the energy storage system and thermal power generating units based on the real-time target power recovery; and a control module, configured to update the real-time target power based on the absorption progress of the power buffer queue in the automatic generation control mode, using the real-time target power as the initial control point, and generate and issue energy storage output commands and thermal power output commands based on the updated real-time target power, so that the total output power of the thermal-storage joint frequency regulation system tracks the real-time target power.

[0014] According to a third aspect of this disclosure, a computer-readable storage medium is provided, the storage medium storing a computer program for executing the scheduling method of the mobile energy storage power vehicle of the first aspect described above.

[0015] According to a fourth aspect of this disclosure, an electronic device is provided, the electronic device comprising: processor; Memory used to store processor-executable instructions; A processor is configured to read executable instructions from memory and execute the instructions to implement the scheduling method for the mobile energy storage power vehicle described in the first aspect above. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a combined fire and energy storage frequency regulation system architecture provided in this disclosure.

[0017] Figure 2This is a flowchart illustrating a combined thermal and energy storage frequency regulation method provided in this disclosure.

[0018] Figure 3 This is a schematic diagram of the priority determination and state switching process of primary and secondary frequency modulation provided in this disclosure.

[0019] Figure 4 This is a schematic diagram of frequency modulation priority determination and state switching provided in this disclosure.

[0020] Figure 5 This is a schematic diagram of an AGC instruction buffer queue mechanism provided in this disclosure during a single frequency modulation period.

[0021] Figure 6 This is a schematic diagram of the three-stage output timing allocation for multi-element energy storage provided in this disclosure.

[0022] Figure 7 This is a schematic diagram of a combined fire and energy storage frequency modulation device provided in this disclosure.

[0023] Figure 8 This is a structural diagram of an electronic device provided in an exemplary embodiment of this disclosure. Detailed Implementation

[0024] To explain this disclosure, exemplary embodiments of the disclosure will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the disclosure, and not all of them. It should be understood that the disclosure is not limited to exemplary embodiments.

[0025] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this disclosure.

[0026] Exemplary System Figure 1 This is a schematic diagram of a combined fire and energy storage frequency regulation system architecture provided in this disclosure.

[0027] like Figure 1As shown, the thermal power and energy storage joint frequency regulation system is generally divided into three layers: the power grid dispatch layer, the power plant control layer, and the equipment execution layer. The power grid dispatch layer includes the provincial power dispatch control center's automatic generation control master station system and frequency acquisition devices (such as synchronous phasor measurement units (PMUs)). The provincial power dispatch control center's automatic generation control master station system is responsible for periodically issuing automatic generation control frequency regulation commands based on the power grid's operating status. The PMU frequency acquisition device acquires the power grid frequency in real time through synchronous phasor measurement technology and transmits the frequency data to the power plant control layer with millisecond-level accuracy. The core of the power plant control layer is the energy management system. The energy management system bidirectionally interfaces with the distributed control system of the thermal power generating units. It can use hard-wiring and ModbusTCP industrial Ethernet dual-redundant communication methods to transmit frequency regulation interlocking signals, status interaction signals, and core command issuance signals. It is the core decision-making unit for realizing primary and secondary frequency regulation coordinated control. The equipment execution layer includes thermal power generating units and various energy storage devices. These energy storage devices include at least a first energy storage device (such as a supercapacitor) and a second energy storage device (such as a lithium-ion battery) with different response speeds. The first energy storage device has a higher response speed than the second. Each energy storage device is independently configured with an energy storage converter connected to the plant service bus, receiving hierarchical commands from the energy management system to perform precise power regulation. The thermal power generating units adjust their output in response to the thermal power output commands from the energy management system. It should be noted that the thermal power-storage combined frequency regulation system may also include more energy storage devices, or it may include only one type of energy storage device; this disclosure does not limit this.

[0028] On the thermal-storage joint frequency regulation system side, the energy management system collects the grid frequency in real time, calculates the frequency deviation and frequency change rate, and determines the current frequency regulation mode based on the frequency deviation and frequency change rate. When it is determined that the primary frequency regulation mode has been entered, the energy management system sets the power command channel corresponding to the automatic generation control to a locked state. Based on the different response speeds of various energy storage devices in the energy storage system, it allocates frequency regulation power output tasks to various energy storage devices at different times. When it is determined that the conditions for the end of the primary frequency regulation mode are met, the energy management system unlocks the locked state, uses the reference power corresponding to the automatic generation control as a basis, and adds the power deviation temporarily stored during the lockout period to obtain the real-time target power, and resumes issuing power commands to the energy storage system and thermal power generating units. In the automatic generation control mode, the energy management system uses the real-time target power as the initial control point, updates the real-time target power based on the absorption progress of the power buffer queue, generates energy storage output commands and thermal power output commands and issues them separately, so that the total output power of the thermal-storage joint frequency regulation system tracks the real-time target power.

[0029] Exemplary methods Figure 2 This is a flowchart illustrating a combined thermal and energy storage frequency regulation method provided in this disclosure. This embodiment can be applied to energy management systems, such as... Figure 2 As shown, steps 210 to 240 are included: Step 210: Receive the grid frequency, based on the frequency deviation of the grid frequency relative to the rated grid frequency and the frequency change rate of the grid frequency.

[0030] For example, the energy management system acquires the grid frequency in real time through a frequency acquisition device, compares the acquired grid frequency with the rated grid frequency, calculates the frequency deviation, and simultaneously calculates the frequency change rate per unit time. The frequency deviation measures the degree to which the grid frequency deviates from its rated value, while the frequency change rate measures how quickly the grid frequency changes. Based on the frequency deviation and frequency change rate, the energy management system determines whether a primary frequency regulation mode needs to be triggered. In this embodiment, the frequency acquisition device can be any station-end measurement device capable of real-time acquisition of grid voltage and frequency electrical quantities, and can interact with the energy management system in real time via an industrial communication link to obtain frequency sampling data.

[0031] The grid frequency is the actual frequency value of the power system during operation, measured in real time by a frequency acquisition device. The rated grid frequency is the nominal operating frequency reference value of the power system, such as 50Hz. The frequency deviation is the algebraic difference between the grid frequency and the rated grid frequency, used to characterize the degree of frequency deviation. The rate of frequency change is the derivative of the frequency deviation with respect to time, used to characterize the rate of frequency change.

[0032] Step 220: When the frequency deviation and frequency change rate meet the conditions for triggering the primary frequency regulation mode, the power command channel corresponding to the automatic generation control is set to the locked state. The power deviation amount corresponding to the automatic generation control adjustment command received during the locked state is stored in the power buffer queue according to the receiving time sequence. Based on the response speed differences of various energy storage devices in the energy storage system, frequency regulation power output tasks are allocated to various energy storage devices at different time periods.

[0033] For example, after calculating the frequency deviation and frequency change rate, the energy management system compares them with corresponding preset thresholds to determine whether to trigger the primary frequency regulation mode. When the triggering condition is met, the energy management system sets the power command channel corresponding to the automatic generation control to a locked state, and the energy storage system stops responding to the automatic generation control adjustment commands. During the locked state, the energy management system continues to receive automatic generation control adjustment commands from the dispatch system, parses the received commands into power deviation values, and stores them in the power buffer queue according to the receiving sequence. Simultaneously, based on the differences in response speed among various energy storage devices in the energy storage system, the energy management system allocates frequency regulation power output tasks to various energy storage devices at different times during the primary frequency regulation response.

[0034] The primary frequency regulation mode refers to the emergency frequency regulation mode in which the combined thermal power and energy storage frequency regulation system automatically and rapidly responds based on its frequency regulation characteristics when the grid frequency deviates from the rated value. The primary frequency regulation mode is automatically determined and triggered by the energy management system based on the grid frequency status, without waiting for instructions from the dispatching system. In primary frequency regulation mode, the energy storage system and thermal power generating units participate in frequency regulation according to preset frequency regulation characteristics, with a response time typically within seconds.

[0035] The power command channel refers to the communication path through which the energy management system sends power regulation commands to the energy storage system. Under normal automatic generation control mode, the energy management system receives automatic generation control and regulation commands from the dispatch system via the power command channel and forwards them to the energy storage system for execution. When the energy management system sets the power command channel to a locked state, the channel is temporarily closed, and the energy management system no longer forwards automatic generation control and regulation commands to the energy storage system.

[0036] The lockout state is a temporary shutdown of the automatic generation control power command channel by the energy management system. During the lockout period, automatic generation control adjustment commands are not issued to the energy storage system for execution, but the energy management system continues to receive and temporarily store these commands. The duration of the lockout corresponds to the activation duration of the primary frequency regulation mode. Once the conditions for ending the primary frequency regulation mode are met, the energy management system releases the lockout and resumes issuing commands to the energy storage system through the power command channel.

[0037] Automatic generation control and regulation commands (AGCs) are power regulation instructions periodically issued by the dispatching system based on the grid's operating status. They are used to eliminate steady-state frequency deviations and restore the system's active power balance. AGCs are issued at fixed intervals (e.g., every 3 seconds) and include power adjustments relative to a reference power level. In a combined thermal power and energy storage frequency regulation system, the energy management system receives the AGCs and forwards them to the energy storage system and thermal power generating units for execution, ensuring that the total output power of the combined frequency regulation system tracks the target power of the AGC.

[0038] Power deviation is the incremental power adjustment of an automatic generation control (ADC) command relative to a reference power. After receiving an ADC command, the energy management system compares the target power in the command with the historical reference power to calculate the power deviation. The power deviation reflects the magnitude and direction (increase or decrease) of the power adjustment (required by the dispatch system for the joint frequency regulation system) and serves as an input parameter for subsequent power allocation calculations.

[0039] The power buffer queue is a data queue that temporarily stores power deviations during the duration of the lockout state, arranged according to the received timing. During the lockout state, the energy management system acquires automatic generation control and adjustment commands sent by the automatic generation control system at preset sampling intervals, parses the automatic generation control and adjustment commands into power deviations, and stores them in the power buffer queue in chronological order. The power buffer queue adopts a first-in, first-out (FIFO) management principle to ensure that the automatic generation control and adjustment commands received during the lockout period are not lost or confused, and are processed sequentially after the primary frequency regulation mode ends.

[0040] An energy storage system is a collection of devices used to store and release electrical energy in a combined thermal power and energy storage frequency regulation system. It is connected to the plant service bus and operates in conjunction with the thermal power generating unit via an energy storage converter. The energy storage system described in this disclosure includes multiple energy storage devices, at least a first energy storage device and a second energy storage device with different response speeds, wherein the first energy storage device has a higher response speed than the second energy storage device. For example, the first energy storage device is a supercapacitor with a response time in the millisecond range, suitable for handling instantaneous power surges; the second energy storage device is a lithium-ion battery with a response time in the second range, suitable for handling continuous power regulation. It should be noted that the type and number of energy storage devices in the energy storage system can be configured according to actual engineering needs, and this disclosure does not limit this.

[0041] Frequency regulation power output tasks are power output commands assigned by the energy management system to various energy storage devices during a single frequency regulation response. Based on the differences in response speed among the various energy storage devices in the system, the energy management system assigns frequency regulation power output tasks to multiple energy storage devices at different times during a single frequency regulation response. In the initial phase, the energy management system instructs the first energy storage device with the fastest response speed to output frequency regulation power, utilizing its fast response characteristics to suppress the initial frequency drop. In the sustained phase, the energy management system instructs the second energy storage device, with a slower response speed but larger energy capacity, to take over power output. In the long-term phase, the energy management system instructs the thermal power generating units to respond at a slower rate in coordination.

[0042] In some embodiments, the energy management system compares the calculated frequency deviation and frequency change rate with corresponding thresholds. When the absolute value of the frequency deviation is greater than or equal to a first deviation threshold, and the duration of the absolute value of the frequency deviation being greater than or equal to the first deviation threshold is greater than the dead zone duration; or, when the absolute value of the frequency change rate is greater than or equal to a change rate threshold, and the absolute value of the frequency deviation is greater than or equal to a second deviation threshold; wherein the second deviation threshold is less than the first deviation threshold; the current frequency modulation mode is determined to be a primary frequency modulation mode.

[0043] The first deviation threshold is the frequency deviation threshold that triggers the primary frequency regulation mode. When the absolute value of the frequency deviation reaches or exceeds this threshold and continues to exceed the dead zone duration, the primary frequency regulation triggering condition is determined to be met. The first deviation threshold can be set according to the power grid frequency regulation standard and the response capability of the thermal power-storage joint frequency regulation system. For example, the first deviation threshold is set to 0.033 Hz, corresponding to the frequency deviation limit specified in the national standard.

[0044] Dead time is a delayed confirmation period to prevent false frequency regulation caused by instantaneous frequency disturbances. The energy management system starts timing after detecting that the absolute value of the frequency deviation has reached a first deviation threshold; if the duration for which the absolute value of the frequency deviation exceeds the first deviation threshold exceeds the dead time, the frequency regulation trigger condition is confirmed. The dead time is set to avoid false triggering caused by instantaneous grid fluctuations or measurement noise; for example, the dead time is set to 200 milliseconds.

[0045] The rate of change threshold is the frequency change rate threshold that triggers primary frequency regulation. When the absolute value of the frequency change rate reaches or exceeds the rate of change threshold, it indicates that the grid frequency is changing rapidly and an emergency frequency regulation response is required. The rate of change threshold, as an auxiliary triggering criterion, together with the frequency deviation threshold, constitutes a dual criterion, enabling the early triggering of primary frequency regulation even when the frequency changes drastically but the deviation has not yet reached the first deviation threshold, thus shortening the response delay. For example, the rate of change threshold is set to 0.1 Hz per second.

[0046] The second deviation threshold is an auxiliary threshold value for frequency deviation used in conjunction with the rate of change threshold. In the dual criterion, when the absolute value of the rate of change of frequency reaches the rate of change threshold, only the absolute value of the frequency deviation needs to reach the second deviation threshold to trigger a primary frequency modulation mode, without needing to reach the higher first deviation threshold. Because the second deviation threshold is smaller than the first deviation threshold, this design allows for triggering primary frequency modulation with a lower frequency deviation requirement in scenarios of rapid frequency changes, improving the system's sensitivity to frequency abrupt events. For example, the second deviation threshold is set to 0.017 Hz.

[0047] For example, in step 210, the energy management system calculates a frequency deviation of -0.065 Hz and a frequency change rate of -0.35 Hz per second. The energy management system compares the absolute value of the frequency deviation (0.065 Hz) with a first deviation threshold (0.033 Hz), where 0.065 Hz is greater than 0.033 Hz; simultaneously, it detects that the duration of this state exceeds the dead zone duration (200 milliseconds). The first condition of the dual criteria is met, and the energy management system determines the current frequency modulation mode as a primary frequency modulation mode. Alternatively, if the absolute value of the frequency deviation is 0.025 Hz (not reaching the first deviation threshold), but the absolute value of the frequency change rate is 0.35 Hz per second (reaching the change rate threshold of 0.1 Hz per second), and the absolute value of the frequency deviation (0.025 Hz) is greater than the second deviation threshold (0.017 Hz), then the second condition of the dual criteria is met, and the current frequency modulation mode is also determined to be a primary frequency modulation mode.

[0048] In this embodiment, by setting a first deviation threshold and a dead time, the energy management system can reliably trigger a frequency regulation when the frequency deviation is consistently large, while avoiding false triggering caused by instantaneous disturbances. By introducing an auxiliary criterion consisting of a frequency change rate threshold and a second deviation threshold, the energy management system can trigger a frequency regulation response in advance in scenarios where the frequency changes drastically but the deviation has not yet reached the first deviation threshold. Through the synergistic effect of the dual criteria, the energy management system achieves differentiated detection and timely response to different types of frequency events, improving the triggering accuracy and response timeliness of the combined thermal power and energy storage frequency regulation system.

[0049] Step 230: If the conditions for ending the primary frequency regulation mode are met, the lockout state is released, and the real-time target power is obtained by superimposing the power deviation based on the reference power corresponding to the automatic power generation control. Based on the real-time target power, power commands are sent to the energy storage system and the thermal power generating unit.

[0050] For example, during the primary frequency regulation mode, the energy management system continuously monitors the grid frequency status and calculates the frequency deviation and frequency change rate. When the grid frequency gradually recovers and stabilizes, the absolute value of the frequency deviation remains below a preset recovery threshold, and the absolute value of the frequency change rate remains below a preset change rate threshold. If this condition persists beyond the recovery confirmation time, the energy management system determines that the primary frequency regulation mode termination condition is met. The energy management system releases the lockout on the automatic generation control power command channel and, with a preset change rate as the upper limit, gradually retrieves the power deviation from the power buffer queue in a first-in-first-out order. The retrieved power deviation is then added to the recovery reference power to obtain the real-time target power for the current automatic generation control. Based on the real-time target power, the energy management system resumes issuing power commands to the energy storage system and thermal power generating units through the power command channel. If the retrieval execution time from the power buffer queue exceeds a preset timeout threshold, the energy management system clears the power buffer queue and recalculates the reference power for automatic generation control based on the current grid frequency deviation, preventing the long-term accumulation of historical deviations from affecting the normal operation of automatic generation control.

[0051] The termination condition is the condition for determining whether the primary frequency regulation mode can be terminated, and is usually determined based on a combination of the degree of frequency deviation recovery and the duration. The termination condition requires the simultaneous fulfillment of three sub-conditions: the absolute value of the frequency deviation is below the recovery threshold, the absolute value of the frequency change rate is below the change rate threshold, and the above conditions persist for more than the recovery confirmation time. This is to prevent frequent switching of the primary frequency regulation mode due to recurring frequency fluctuations during the recovery process. The recovery threshold is the frequency deviation threshold for determining whether the frequency has recovered to the allowable range. For example, the recovery threshold is set to 0.020 Hz, which is lower than the trigger threshold, forming a hysteresis design. The recovery confirmation time is the minimum continuous observation time required to determine stable frequency recovery. For example, the recovery confirmation time is set to 3 seconds. The reference power is the power reference value in the automatic generation control mode, and is the basis for calculating the power deviation. The real-time target power is the power adjustment target value of the automatic generation control at the current moment, obtained by superimposing the reference power and the power deviation taken from the power buffer queue. The rate of change is the upper limit of the rate at which the power deviation is taken from and superimposed in the power buffer queue, used to control the rate of power change during the switching process from primary frequency regulation to automatic generation control mode, avoiding power step jumps. The timeout threshold is the maximum execution time allowed for the power cache queue depletion process. If this time is exceeded, the queue will be forcibly emptied and the baseline power will be recalculated. For example, the timeout threshold is set to 300 seconds.

[0052] In some embodiments, after the termination condition is met continuously for more than the recovery confirmation time, the lockout state of the automatic generation control mode is released. The power deviation amount is gradually retrieved from the power buffer queue at a preset change rate as the upper limit, and the power deviation amount is added to the recovery reference power to obtain the real-time target power of the current automatic generation control. The automatic generation control is instructed to resume issuing power commands to the energy storage system and the thermal power generating unit based on the real-time target power. If the retrieval execution time of the power buffer queue exceeds a preset timeout threshold, the power buffer queue is cleared and the reference power of the automatic generation control is recalculated based on the current grid frequency deviation.

[0053] The purpose of the recovery confirmation time is to ensure the continuity of the frequency recovery state and avoid frequent switching of the blocking state due to frequency fluctuations around the recovery threshold. The energy management system starts the recovery confirmation timer after detecting that both the absolute value of the frequency deviation and the absolute value of the frequency change rate are below the corresponding thresholds. Only when the above state continues for more than the recovery confirmation time is the termination condition confirmed and the unlocking operation executed. The preset change rate limits the rate of power change during the power buffer queue absorption process, ensuring a smooth transition in real-time target power and avoiding power step surges when switching from primary frequency regulation to automatic generation control mode. The timeout protection mechanism prevents the automatic generation control from deviating from normal operation due to the power buffer queue remaining unemptied for an extended period under abnormal conditions. When the absorption time exceeds the preset timeout threshold, the energy management system proactively discards historical buffer data and recalculates the reference power based on the current actual grid frequency deviation, ensuring that automatic generation control can adjust based on the latest grid conditions.

[0054] For example, the energy management system determines that the termination condition is met when it detects an absolute value of 0.015 Hz for the frequency deviation (less than the recovery threshold of 0.020 Hz) and an absolute value of 0.02 Hz per second for the frequency change rate (less than the change rate threshold of 0.1 Hz per second), and this condition persists for more than the recovery confirmation time (3 seconds). The energy management system then releases the lockout state and, with a preset change rate cap of 1 MW per second, retrieves the power deviation amount from the power buffer queue one by one and adds it to the recovery reference power. Assuming the recovery reference power is 300 MW and the cumulative power deviation amount temporarily stored in the power buffer queue is 10 MW, the energy management system gradually adjusts the real-time target power from 300 MW to 310 MW at a rate not exceeding 1 MW per second, with the entire process lasting approximately 10 seconds. Based on the updated real-time target power, the energy management system resumes issuing power commands to the energy storage system and the thermal power generating unit. If the execution time for retrieving power from the power buffer queue exceeds the preset timeout threshold (300 seconds), the energy management system will clear the power buffer queue and recalculate the base power for automatic generation control based on the current grid frequency deviation, which is 305 MW, and use this value as the new adjustment starting point.

[0055] In this embodiment, by setting termination conditions and recovery confirmation time, the energy management system can release the lockout only after the frequency is truly stable, avoiding repeated switching caused by frequency fluctuations; by gradually phasing out the power buffer queue at a preset change rate as the upper limit, a smooth switching from primary frequency regulation to automatic generation control mode is achieved, avoiding the impact of power step on the power grid; by setting an overtime protection mechanism, the long-term impact of abnormal accumulation of the power buffer queue on automatic generation control is prevented, ensuring the reliable operation of the system.

[0056] To better understand the priority determination and state switching process of primary and secondary frequency modulation, the following will combine... Figure 3 The diagram illustrating the primary and secondary frequency modulation priority determination and state switching is provided as an example.

[0057] like Figure 3As shown, the energy management system initially operates normally, monitoring the grid frequency deviation in real time. When the absolute value of the frequency deviation is greater than or equal to the trigger threshold, the energy management system triggers primary frequency regulation and enters the primary frequency regulation activation state, while simultaneously forcibly locking the automatic generation control command channel. In the primary frequency regulation activation state, the energy management system executes frequency regulation power output according to the preset multi-energy storage output allocation strategy. When the absolute value of the frequency deviation is less than the recovery threshold and the frequency change rate meets the recovery conditions, and continues to reach the recovery confirmation time, the energy management system meets the exit criteria, smoothly transitions through the unlocked buffer state, gradually eliminates the automatic generation control deviation in the power buffer queue, and finally returns to normal operation without disturbance. The transition conditions between each state form a complete directed state machine, ensuring the determinism and traceability of the priority determination logic. Among them, the frequency regulation priority system is: primary frequency regulation (highest priority) > automatic generation control (second highest priority) > day-ahead planned output (lowest priority). When a high-priority frequency regulation mode is activated, it forcibly overrides the low-priority command and retains its accumulated deviation, which is eliminated in an orderly manner after the high-priority mode exits. Primary frequency regulation has a higher priority than automatic generation control. When primary frequency regulation is activated, the automatic generation control command is forcibly locked and temporarily stored.

[0058] To better understand the priority determination and state switching process of frequency modulation, the following will combine... Figure 4 The diagram illustrating frequency modulation priority determination and state switching is provided as an example.

[0059] like Figure 4 As shown, the figure contains three time-series curves: the upper curve represents the grid frequency deviation Δf, indicating the difference between the grid frequency and the rated grid frequency; the middle curve represents the total energy storage output P, ​​representing the sum of the output power of each energy storage device in the energy storage system; and the lower curve represents the automatic generation control reference power, indicating the target power reference value issued by the energy management system to the energy storage system under automatic generation control mode. Three time points are marked in the figure: The moment when the absolute value of the frequency deviation first falls below the recovery threshold, the system enters the hysteresis observation window and begins to monitor the persistence of the frequency recovery state. When the frequency recovery state continues until the recovery confirmation time is reached, the unlock buffer operation is triggered, and the energy management system begins to gradually eliminate the power deviation temporarily stored in the power buffer queue. The moment when the power deviation converges to within the recovery threshold range, the switching is complete, and the system fully returns to the automatic power generation control master mode. to The phase is the hysteresis observation window phase (1~30s), during which the energy management system continuously monitors the frequency recovery status; to The unlocking buffer phase (greater than 30 seconds) involves the instructions in the power buffer queue gradually tracking the automatic generation control reference power at a preset rate of change. The total energy storage output curve exhibits a smooth transition without any abrupt changes. The amplitude of the frequency secondary disturbance during the entire transition process is controlled within the recovery threshold. At the moment of unlocking, the actual energy storage output at the end of the first frequency regulation is used as the benchmark. This benchmark output is the actual output of the energy storage system at the moment of unlocking, and the automatic generation control increment is superimposed on this benchmark output, thus avoiding power abrupt changes.

[0060] Step 240: In the automatic power generation control mode, the real-time target power is used as the initial control point. The real-time target power is updated based on the absorption progress of the power buffer queue. Energy storage output command and thermal power output command are generated and issued based on the updated real-time target power, so that the total output power of the thermal-storage joint frequency regulation system tracks the real-time target power.

[0061] For example, after the energy management system enters the automatic generation control mode, it uses the real-time target power obtained in step 230 as the initial control point. The energy management system continuously monitors the absorption progress of the power deviation in the power buffer queue and updates the real-time target power according to the absorption progress. Specifically, each time the energy management system completes a power buffer queue retrieval operation, it adds the retrieved power deviation to the current real-time target power to obtain the updated real-time target power. Based on the updated real-time target power, the energy management system generates energy storage output commands and thermal power output commands according to a preset power allocation strategy, and issues them to the energy storage system and the thermal power generating unit. The energy storage system adjusts the output power of each energy storage device according to the energy storage output commands, and the thermal power generating unit adjusts its output according to the thermal power output commands, so that the total output power of the thermal-storage joint frequency regulation system tracks the real-time target power, realizing the automatic generation control to track and regulate the power demand of the power grid.

[0062] The automatic generation control mode refers to the regulation mode in which the energy management system controls the output power of the combined thermal power and energy storage frequency regulation system to track the target power based on the automatic generation control and regulation commands issued by the dispatching system. In automatic generation control mode, the energy management system receives power regulation commands from the dispatching system at fixed intervals and allocates power according to the grid operating status. The initial control point is the initial power reference value when the energy management system enters the automatic generation control mode, obtained by superimposing the power deviation on the reference power in step 230. The absorption progress of the power buffer queue reflects the proportion of automatic generation control and regulation commands temporarily stored during the lockout period that are gradually executed; the absorption progress determines the update frequency and amplitude of the real-time target power. The energy storage output command is the power regulation command issued by the energy management system to the energy storage system, instructing each energy storage device to output a specified power value. The thermal power output command is the power regulation command issued by the energy management system to the thermal power generating unit, instructing the unit to adjust its output to a specified level.

[0063] The thermal energy storage joint frequency regulation method provided in this disclosure enables the energy management system to promptly perceive the grid frequency status by receiving the grid frequency and calculating the frequency deviation and frequency change rate. By setting the power command channel corresponding to automatic generation control to a locked state and storing the power deviation in a power buffer queue when trigger conditions are met, direct interference of automatic generation control commands to the energy storage system during primary frequency regulation is avoided. By allocating frequency regulation power output tasks at different times based on the response speed differences of various energy storage devices, the characteristic advantages of different energy storage devices are fully utilized. By releasing the lockout after the termination condition is met and obtaining the real-time target power by superimposing the power deviation with the reference power, a seamless switching from primary frequency regulation to automatic generation control mode is achieved. By updating the real-time target power based on the absorption progress of the power buffer queue in automatic generation control mode, the automatic generation control can smoothly continue the temporary adjustment needs stored during primary frequency regulation, thereby improving the coordinated control performance of primary frequency regulation and automatic generation control in the thermal energy storage joint frequency regulation system.

[0064] In some embodiments, step 220 may include steps 310 to 330.

[0065] Step 310: Set the power command channel to the locked state, so that the energy storage system stops responding to the automatic generation control and regulation command.

[0066] For example, after determining in step 220 that the conditions for triggering the primary frequency regulation mode are met, the energy management system immediately executes a lockout operation on the power command channel. The energy management system sends a lockout signal to the energy storage system, notifying it to stop responding to automatic generation control commands. Upon receiving the lockout signal, the energy storage system only responds to power commands in the primary frequency regulation mode and no longer executes power regulation commands in the automatic generation control mode. The lockout operation on the power command channel is completed within milliseconds, ensuring that the primary frequency regulation response is not interfered with by automatic generation control commands.

[0067] Specifically, the power command channel interlocking refers to the energy management system actively cutting off the communication path for forwarding automatic power generation control and regulation commands to the energy storage system, causing the energy storage system to receive and execute only primary frequency regulation mode power commands for a certain period of time. The timing of the interlocking operation is determined by the energy management system based on the results of frequency deviation and frequency change rate judgments, and the duration of the interlocking is consistent with the activation duration of the primary frequency regulation mode. The behavior mode of the energy storage system in the interlocked state is uniformly managed by the energy management system through preset control logic.

[0068] Step 320: Acquire the automatic power generation control adjustment command sent by the automatic power generation control system at a preset sampling period interval, and parse the automatic power generation control adjustment command into a power deviation.

[0069] For example, after setting the power command channel to a locked state, the energy management system continues to obtain regulation commands from the automatic generation control system at preset sampling intervals. During the locked state, the automatic generation control function of the dispatching system continues to operate normally and continuously generate regulation commands, but these commands are no longer directly issued to the energy storage system for execution. After receiving the automatic generation control regulation command, the energy management system first performs a validity check, then extracts the target power value from the command, compares the target power with the historical reference power, and calculates the power deviation. The sign of the power deviation indicates the direction of power adjustment; a positive value indicates a request to increase output, and a negative value indicates a request to decrease output. After each parsing, the energy management system appends a receiving timestamp and command sequence number to the power deviation, forming a complete queue record, waiting to be written into the power buffer queue.

[0070] The preset sampling period is the time interval at which the energy management system receives automatic generation control adjustment commands. For example, the preset sampling period is set to 500 milliseconds. The automatic generation control system issues adjustment commands at a fixed period (e.g., every 3 seconds). The energy management system's sampling period is shorter than the automatic generation control system's command issuance period to ensure that no adjustment command is missed. The analytical calculation of the power deviation refers to the energy management system performing algebraic operations between the target power in the automatic generation control adjustment command and the historical reference power to obtain the power increment that needs to be adjusted. The historical reference power is the power reference value in the automatic generation control mode before the blocking trigger moment, serving as the basis for calculating the power deviation.

[0071] Step 330: Store the power deviation in the power buffer queue in chronological order.

[0072] For example, after obtaining the power deviation, the energy management system stores the power deviation into a power buffer queue according to the reception sequence. The power buffer queue adopts a First-In, First-Out (FIFO) data structure, and each stored record contains the power deviation value, reception timestamp, and instruction sequence number. The energy management system writes the newly parsed power deviation from the tail of the queue, with the first received power deviation at the head and the last received at the tail, ensuring that the instruction order is not disordered. The power buffer queue has a capacity limit, for example, a capacity limit of 60 records, corresponding to approximately 1 minute of automatic generation control instruction data. When there are already 60 records in the queue, if a new power deviation is parsed as the 61st record, the energy management system automatically discards the earliest stored record at the head of the queue and writes the new record to the tail of the queue, always keeping the latest 60 scheduling instructions in the queue, avoiding the queue from growing indefinitely due to the long duration of a single frequency regulation. After the storage operation is completed, the energy management system continues to execute steps 320 and 330 repeatedly at a preset sampling period until the end condition of the single frequency regulation mode is met.

[0073] The power buffer queue is a data buffer that stores power deviations in chronological order. Each record in the queue is sorted by its received timestamp, with the earliest received power deviation at the front of the queue and the latest received at the back. During the unlocking and recovery phase after a frequency modulation mode ends, the energy management system retrieves the power deviations sequentially from the front of the queue and adds them to the recovery reference power, thus achieving the orderly elimination of temporarily stored instructions during the lockout period. The queue capacity limit is the maximum number of records that the power buffer queue can store. For example, the queue capacity limit is set to 120 records (corresponding to 1 minute of data, calculated based on a 500-millisecond sampling period).

[0074] To better understand the buffer queue mechanism of automatic generation control commands during primary frequency regulation, the following section will combine... Figure 5 The diagram shown illustrates the AGC instruction buffer queue mechanism during a single frequency modulation period.

[0075] like Figure 5 As shown, after a frequency regulation mode is triggered, the energy management system immediately sets the automatic generation control power command channel to a locked state, and the energy storage system no longer responds to the automatic generation control adjustment commands. However, the automatic generation control function of the dispatching system continues to operate, continuously generating adjustment commands. The energy management system acquires these commands at preset sampling intervals, parses each command into a power deviation, and each power deviation is represented by ΔPAGC(k), where k is the command reception sequence number. The parsed power deviations are stored in a first-in-first-out power buffer queue according to the reception sequence. The mathematical representation of the power buffer queue is Q={ΔPAGC(1), ΔPAGC(2), ..., ΔPAGC(n)}, where ΔPAGC(k) is the power deviation corresponding to the k-th received automatic generation control adjustment command, and n is the total number of commands stored in the queue. The cumulative power of the queue is represented by Pbuf, i.e., Pbuf=ΣΔPAGC(k), k=1 to n, representing the total amount of automatic generation control deviations temporarily stored during the lockout period. The power buffer queue has a maximum capacity of 60 entries, corresponding to a 1-minute automatic generation control command update cycle. When the queue reaches its maximum of 60 entries, the oldest command at the head of the queue is automatically discarded, while the most recently written scheduling command is retained, ensuring the queue does not grow indefinitely. During the unlocking and recovery phase after the primary frequency regulation mode ends, the energy management system retrieves the power deviation from the head of the queue one by one, using a preset change rate as the upper limit. The retrieved power deviation is then added to the recovery reference power, gradually absorbing the temporarily stored commands in the queue. When the power deviation converges to within the recovery threshold range, the switchover is complete, and the system fully reverts to the automatic generation control master mode. Throughout the entire process, the power commands of the primary frequency regulation and the power adjustment requirements of the automatic generation control are completely isolated in timing, avoiding the superposition or conflict of commands from the two control modes.

[0076] During the period of the lockout, if the difference between the power command of the primary frequency regulation mode and the historical reference power of the automatic generation control exceeds the power limit of the energy storage system, the power over-limit protection will be triggered.

[0077] Power over-limit protection is a safety mechanism that monitors the operational safety of the energy storage system during the continuous blocking state. The energy management system calculates in real time the difference between the power command in primary frequency regulation mode and the historical reference power of automatic generation control. This difference reflects the power deviation of the energy storage system relative to normal operation when undertaking primary frequency regulation power output. When this difference exceeds the power limit of the energy storage system, it indicates that the output demand of the energy storage system exceeds its safe operating range, which may cause equipment overload. After the power over-limit protection is triggered, the energy management system takes preset protection measures, including limiting the amplitude of the primary frequency regulation power command or switching part of the output to the thermal power generating unit, to ensure the safe operation of the energy storage system within the rated power range.

[0078] The power limit of an energy storage system is the sum of the rated power of all energy storage devices in the system, representing the maximum power that the system can continuously output. This power limit is dynamically calculated by the energy management system based on the current available power and operating status of each energy storage device. The historical reference power is the power reference value under automatic generation control mode before the blocking trigger moment, serving as the power reference point for power limit protection judgment.

[0079] For example, the energy storage system has a power limit of 30 MW and a historical reference power of 300 MW. During a primary frequency regulation response, the energy management system issues a primary frequency regulation power command of 340 MW, which differs from the historical reference power by 40 MW, exceeding the energy storage system's power limit of 30 MW. The energy management system triggers the power over-limit protection, limiting the energy storage system's output to the power limit of 30 MW. The excess 10 MW of power deficit is supplemented by thermal power generating units at a preset slow rate.

[0080] In this embodiment, by setting the power command channel to a locked state, the energy storage system stops responding to automatic generation control adjustment commands during primary frequency regulation, thus preventing the primary frequency regulation power commands and automatic generation control adjustment commands from overlapping or offsetting on the energy storage system side. By acquiring and parsing the automatic generation control adjustment commands as power deviations at preset sampling intervals, it is ensured that the adjustment intentions of the scheduling system are not lost. By storing the power deviations in a power buffer queue in chronological order, the orderly temporary storage of automatic generation control adjustment commands during the locked period is achieved, providing a data foundation for subsequent smooth absorption. Through the power over-limit protection mechanism, overload operation of the energy storage system is prevented in high-power output scenarios during primary frequency regulation, ensuring equipment safety and frequency regulation reliability.

[0081] In some other embodiments, step 220 may include steps 410 to 430.

[0082] Step 410: In the initial stage of a frequency modulation response, the first energy storage device in the energy storage system, which is instructed to have a first response speed, outputs a first frequency modulation power.

[0083] For example, after a frequency regulation response begins, the energy management system immediately enters the initial stage of power distribution control. The energy management system sends a first frequency regulation power command to the first energy storage device, instructing the first energy storage device to output the first frequency regulation power at the maximum available power. Upon receiving the command, the first energy storage device utilizes its millisecond-level response characteristics to reach the first frequency regulation power output value within 50 milliseconds, quickly providing high power support to suppress the initial frequency drop.

[0084] The initial phase is the period after the frequency regulation response begins, during which the fast-response energy storage device bears the main power output. The duration of the initial phase can be 0 to 1 second. During this period, the grid frequency drops most rapidly, requiring high-power rapid support to suppress further frequency degradation. The duration of the initial phase can be configured based on the rated energy and frequency regulation requirements of the first energy storage device. The first energy storage device is an energy storage unit with a higher response speed than the second energy storage device in the energy storage system.

[0085] like Figure 6 As shown, the first energy storage device is a supercapacitor with a power response time of no more than 10 milliseconds and a cycle life of up to one million cycles, making it suitable for handling instantaneous power surges. The first frequency regulation power is the target power output value allocated to the first energy storage device by the energy management system in the initial stage. For example, the first frequency regulation power is set to the rated power of the first energy storage device, enabling the first energy storage device to quickly respond to frequency drops at full power output.

[0086] Step 420: In the continuous phase following the initial phase, the second energy storage device in the energy storage system with the second response speed is instructed to output the second frequency regulation power, and the first energy storage device is instructed to reduce the first frequency regulation power to the preset maintenance power at a preset derating rate.

[0087] For example, after the initial phase ends, the energy management system enters the continuous phase of power distribution control. The energy management system sends a second frequency regulation power command to the second energy storage device, instructing the second energy storage device to gradually take over the output of the first energy storage device; simultaneously, the energy management system sends a derating command to the first energy storage device, instructing the first energy storage device to reduce the first frequency regulation power to a preset maintenance power at a preset derating rate. The second energy storage device increases its output power at a preset ramp rate, and the first energy storage device decreases its output power at a preset derating rate. The two power curves are smoothly connected in the continuous phase, avoiding any breaks or abrupt changes in power output.

[0088] The sustained phase is the period after the initial phase where the continuous energy storage device takes over the power output. The typical duration of the sustained phase is 1 to 30 seconds. During this period, the rate of grid frequency drop slows down, but continuous power support is required to maintain frequency stability. The second energy storage device is an energy storage device in the system with a lower response time than the first energy storage device but a larger energy capacity. For example, the second energy storage device is a lithium-ion battery with a power response time of no more than 300 milliseconds and a large energy capacity, suitable for handling continuous power regulation at the second to minute level. The second frequency regulation power is the target power output value allocated to the second energy storage device by the energy management system during the sustained phase. The value of the second frequency regulation power is dynamically calculated based on the total power demand of the primary frequency regulation and the derating progress of the first energy storage device. The preset derating rate is the rate limit for the first energy storage device to reduce its power output from the first frequency regulation power to the preset maintenance power. For example, the preset derating rate is set to 0.5 megawatts per second. The preset sustaining power is the minimum output power at which the first energy storage device maintains operation during the continuous phase, used to keep the first energy storage device in a standby response state. For example, the preset sustaining power is set to 10% of the rated power of the first energy storage device.

[0089] Step 430: In the long-term phase following the continuous phase, the thermal power generating unit is instructed to output frequency-regulated power at a preset slow rate to coordinate with the second energy storage device.

[0090] For example, after the continuous phase ends, the energy management system enters the long-term power distribution control phase. The energy management system sends a frequency regulation power command to the thermal power generating unit, instructing the unit to output frequency regulation power at a preset slow rate, working in conjunction with the second energy storage device to maintain frequency stability. During the long-term phase, the second energy storage device gradually reduces its output to standby level, while the output of the thermal power generating unit gradually increases, achieving a smooth transition in output between the energy storage device and the thermal power generating unit.

[0091] The long-duration phase is the period following the sustained phase where thermal power units work in conjunction with energy storage devices to provide power. The long-duration phase typically begins after 30 seconds. During this period, the grid frequency has stabilized, and the primary objective is for the thermal power units to undertake long-term power regulation, allowing the energy storage devices to return to standby mode to handle potential subsequent frequency events. The preset slow rate is the upper limit of the frequency regulation power output of the thermal power units. For example, the preset slow rate is set to no more than 1% of the rated power per minute. This rate setting takes into account the mechanical inertia and thermal stress limitations of the thermal power units, preventing operational safety from being affected by rapid load changes.

[0092] In this embodiment, by instructing the first energy storage device to output the first frequency regulation power in the initial stage of the frequency regulation response, the millisecond-level response characteristics of the first energy storage device are utilized to quickly suppress the initial frequency drop, thereby improving the system's response speed to frequency mutations. By instructing the second energy storage device to take over the output and instructing the first energy storage device to derating to the maintenance power in the continuous stage, a smooth transition of output between energy storage devices is achieved, avoiding power output interruptions. By instructing the thermal power generating unit to output power at a slow rate in the long stage, the energy storage devices gradually return to standby state, extending the available frequency regulation time of the energy storage devices. Through the three-stage time-sharing output allocation strategy, the technical characteristics and advantages of different types of energy storage devices are fully utilized, achieving optimal matching of full-cycle frequency regulation capabilities.

[0093] In some embodiments, when the state of charge (SOC) of the first energy storage device is below a first lower SOC limit or above a first upper SOC limit, the energy management system instructs the first energy storage device to reduce its output power to less than the first frequency regulation power; when the SOC of the second energy storage device is below a second lower SOC limit or above a second upper SOC limit, the energy management system reduces the output power of the second energy storage device to less than the second frequency regulation power. When the output power of the first energy storage device is less than the first frequency regulation power, or the output power of the second energy storage device is less than the second frequency regulation power, the energy management system calculates the total frequency regulation power deficit and controls the thermal power generating unit to supplement the total frequency regulation power deficit at a preset slow adjustment rate.

[0094] The state of charge (SBC) is the ratio of the current remaining charge of an energy storage device to its rated capacity, used to characterize the remaining energy level of the energy storage device. The first lower charge limit and the first upper charge limit are the safe operating SBC boundary values ​​for the first energy storage device; for example, the first lower charge limit is set to 20%, and the first upper charge limit is set to 90%. The second lower charge limit and the second upper charge limit are the safe operating SBC boundary values ​​for the second energy storage device; for example, the second lower charge limit is set to 15%, and the second upper charge limit is set to 90%. When the SBC of any energy storage device exceeds the safe boundary, the energy management system reduces the output power of that energy storage device to ensure device safety. The total frequency regulation power deficit is the power shortfall caused by the reduced output of energy storage devices due to SBC protection, calculated by the energy management system and allocated to the thermal power generating units for supplementation. The preset slow regulation rate is the upper limit of the rate at which the thermal power generating units supplement the total frequency regulation power deficit, consistent with the preset slow rate.

[0095] For example, during a frequency regulation response, the energy management system detects that the state of charge (SBC) of the first energy storage device has dropped to 18% (below the first lower charge limit of 20%), and instructs the first energy storage device to reduce its output power from 15 MW to 5 MW. Simultaneously, the second energy storage device maintains an output of 15 MW. The reduction in output power of the first energy storage device results in a total frequency regulation power deficit of 10 MW, which the energy management system controls the thermal power generating unit to compensate for at a preset slow regulation rate (1% of rated power per minute, i.e., 6 MW per minute).

[0096] In this embodiment, by setting a range for the ratio of the first rated power to the total power, it is ensured that the first energy storage device has sufficient power output capability in the initial stage to suppress frequency drops, while the second energy storage device has sufficient power margin to take over output in the continuous stage, thus achieving a reasonable power configuration of different energy storage devices. By reducing the output power of the first or second energy storage device when its state of charge exceeds the safety boundary, it is ensured that the energy storage devices operate within a safe operating range, avoiding damage to the equipment lifespan caused by overcharging and over-discharging. By calculating the total frequency regulation power deficit and controlling the thermal power generating unit to supplement it at a preset slow adjustment rate, it is ensured that the power gap caused by the reduction in the output of the energy storage devices is filled in a timely manner, maintaining the continuity and stability of the frequency regulation power output.

[0097] In some embodiments, when the frequency regulation mode is primary frequency regulation mode, the energy management system calculates the primary frequency regulation total power command based on the deviation of the grid frequency from the rated frequency according to the preset frequency regulation characteristic coefficient; the primary frequency regulation total power command is used as the basis for allocating the frequency regulation power output tasks of various energy storage devices, and instructs the energy storage system to output frequency regulation power according to the allocation result; when the available total power of the energy storage system is less than the primary frequency regulation total power command, the thermal power generating unit supplements the power deficit at a preset slow rate.

[0098] To better understand the control architecture of the energy management system in frequency regulation mode, the following section will combine... Figure 6 The diagram illustrating the three-tiered control architecture of the EMS is provided as an example. Figure 6As shown, the control architecture of the energy management system is divided into three layers: the scheduling decision layer (also known as the minute-level optimized scheduling layer), the coordination control layer (also known as the second-level coordination control layer), and the equipment execution layer (also known as the millisecond-level fast control layer). The scheduling decision layer, located at the top layer of the architecture, operates on a minute-level timescale. It is responsible for receiving automatic power generation control commands from the grid, executing the state-of-charge (SOC) balancing management and SOC recovery plans for energy storage devices, scheduling planned output and optimizing the coordinated output of thermal power plants, and outputting power reference commands for each energy storage unit. The coordination control layer, located in the middle layer of the architecture, operates on a second-level timescale. It implements primary and secondary frequency regulation priority determination, interlocking and unlocking state machine management, power buffer queue reading and writing, and multi-energy storage power allocation calculation. It is the core logic carrier layer of the thermal-energy storage joint frequency regulation method. The equipment execution layer, located at the bottom layer of the architecture, operates on a millisecond-level timescale. It directly drives each energy storage converter to complete real-time power tracking and feeds back real-time SOC, current, temperature, and other state variables to the upper layer. The three layers communicate using standardized interfaces, with clear boundaries of responsibility for each layer. Modular expansion and independent upgrades are supported, and higher-level control must not override activated frequency modulation protection commands of lower layers.

[0099] For example, when the frequency regulation mode is primary frequency regulation mode, the energy management system first determines the current frequency regulation mode through the primary frequency regulation priority determination module of the coordination control layer. The coordination control layer calculates the total primary frequency regulation power command based on the deviation of the grid frequency from the rated frequency, according to a preset frequency regulation characteristic coefficient. The preset frequency regulation characteristic coefficient is a coefficient characterizing the proportional relationship between frequency deviation and frequency regulation power. For example, the preset frequency regulation characteristic coefficient is set to a frequency regulation response of 3% of rated power for every 0.1 Hz deviation. The energy management system uses the calculated total primary frequency regulation power command as the basis for allocating frequency regulation power output tasks for various energy storage devices, and instructs the energy storage system to output frequency regulation power according to the allocation results, following the three-stage output allocation strategy described in steps 410 to 430. When the total available power of the energy storage system is less than the total primary frequency regulation power command, the energy management system calculates the power deficit, and the thermal power generating unit supplements the power deficit at a preset slow rate to ensure the integrity of the frequency regulation power output. The device execution layer tracks power commands in real time and feeds back the state of charge and output status of each energy storage device to the coordination and control layer. The coordination and control layer dynamically adjusts the power allocation strategy based on the feedback information.

[0100] In this embodiment, by calculating the primary frequency regulation total power command based on the grid frequency deviation according to the preset frequency regulation characteristic coefficient, the energy management system can accurately calculate the required frequency regulation power response according to the degree of frequency deviation, thus realizing the quantification of frequency regulation power demand. By using the primary frequency regulation total power command as the basis for allocating frequency regulation power output tasks of various energy storage devices, the rational allocation of frequency regulation power among different types of energy storage devices is realized, giving full play to the technical characteristics of each energy storage device. Through the EMS three-layer hierarchical control architecture, the separation of responsibilities and collaborative operation of frequency regulation decision-making, coordinated control and equipment execution are realized. Each layer communicates with each other through standardized interfaces, supporting modular expansion and independent upgrades. When the total available power of the energy storage system is insufficient, the thermal power generating unit supplements the power deficit at a preset slow rate, ensuring the integrity of frequency regulation power output and system reliability.

[0101] Exemplary device Figure 7 This is a schematic diagram of a combined thermal and energy storage frequency regulation device provided in this disclosure. Figure 4 As shown, the combined thermal power and energy storage frequency modulation device 700 includes a receiving module 710, a distribution module 720, a recovery module 730, and a control module 740. Wherein: The receiving module 710 is configured to receive the power grid frequency and determine the frequency deviation of the power grid frequency relative to the rated power grid frequency and the frequency change rate of the power grid frequency. The allocation module 720 is configured to set the power command channel corresponding to the automatic generation control to a locked state when the frequency deviation and frequency change rate meet the conditions for triggering the primary frequency regulation mode, store the power deviation amount corresponding to the automatic generation control adjustment command received during the locked state into the power buffer queue according to the receiving time sequence, and allocate frequency regulation power output tasks to multiple energy storage devices at different time periods based on the response speed differences of multiple energy storage devices in the energy storage system. The recovery module 730 is configured to release the lockout state when the conditions for the end of the primary frequency regulation mode are met, obtain the real-time target power by superimposing the power deviation based on the reference power corresponding to the automatic power generation control, and send power commands to the energy storage system and thermal power generating unit based on the real-time target power recovery. The control module 740 is configured to, in automatic generation control mode, use the real-time target power as the initial control point, update the real-time target power based on the absorption progress of the power buffer queue, and generate and issue energy storage output commands and thermal power output commands based on the updated real-time target power, so that the total output power of the thermal-storage joint frequency regulation system tracks the real-time target power.

[0102] In some embodiments, the allocation module 410 is configured to determine the current frequency modulation mode as a primary frequency modulation mode when the absolute value of the frequency deviation is greater than or equal to a first deviation threshold and the duration of the absolute value of the frequency deviation being greater than or equal to the first deviation threshold is greater than the dead time; or, when the absolute value of the frequency change rate is greater than or equal to a change rate threshold and the absolute value of the frequency deviation is greater than or equal to a second deviation threshold; wherein the second deviation threshold is less than the first deviation threshold.

[0103] In some embodiments, the allocation module 720 is configured to set the power command channel to a locked state, causing the energy storage system to stop responding to the automatic generation control adjustment command; acquire the automatic generation control adjustment command sent by the automatic generation control system at preset sampling intervals, and parse the automatic generation control adjustment command into a power deviation; store the power deviation in the power buffer queue in chronological order; wherein, during the period of the locked state, if the difference between the power command of the primary frequency regulation mode and the historical reference power of the automatic generation control adjustment exceeds the power limit of the energy storage system, the power over-limit protection is triggered.

[0104] In some embodiments, the allocation module 720 is configured to, in the initial phase of a frequency regulation response, instruct a first energy storage device with a first response speed in the energy storage system to output a first frequency regulation power; in the sustained phase following the initial phase, instruct a second energy storage device with a second response speed in the energy storage system to output a second frequency regulation power, and instruct the first energy storage device to reduce the first frequency regulation power to a preset maintenance power at a preset derating rate; and in the long-term phase following the sustained phase, instruct the thermal power generating unit to output frequency regulation power at a preset slow rate to coordinate with the second energy storage device.

[0105] In some embodiments, the allocation module 720 is configured such that the ratio of the first rated power corresponding to the first energy storage device to the sum of the first rated power and the second rated power corresponding to the second energy storage device is within a preset range; wherein the energy capacity of the first energy storage device is less than that of the second energy storage device; when the state of charge of the first energy storage device is lower than the first lower limit of charge or higher than the first upper limit of charge, the first energy storage device is instructed to reduce its output power to less than the first frequency regulation power; or, when the state of charge of the second energy storage device is lower than the second lower limit of charge or higher than the second upper limit of charge, the output power of the second energy storage device is reduced to less than the second frequency regulation power; when the output power of the first energy storage device is less than the first frequency regulation power or the output power of the second energy storage device is less than the second frequency regulation power, the total frequency regulation power deficit is calculated, and the thermal power generating unit is controlled to supplement the total frequency regulation power deficit at a preset slow adjustment rate.

[0106] In some embodiments, the recovery module 730 is configured to release the lockout state of the automatic generation control mode after the termination condition is continuously met for more than the recovery confirmation time; gradually retrieve the power deviation amount from the power buffer queue with a preset change rate as the upper limit, add the power deviation amount to the recovery reference power to obtain the real-time target power of the current automatic generation control; instruct the automatic generation control to resume the power command issuance to the energy storage system and thermal power generating unit based on the real-time target power; if the retrieval execution time of the power buffer queue exceeds a preset timeout threshold, clear the power buffer queue and recalculate the reference power of the automatic generation control with the current grid frequency deviation.

[0107] In some embodiments, the allocation module 720 is configured to calculate the primary frequency regulation total power command based on the deviation of the grid frequency from the rated frequency and according to a preset frequency regulation characteristic coefficient; use the primary frequency regulation total power command as the basis for allocating the frequency regulation power output tasks of various energy storage devices, and instruct the energy storage system to output frequency regulation power according to the allocation result; when the available total power of the energy storage system is less than the primary frequency regulation total power command, the thermal power generating unit supplements the power deficit at a preset slow rate.

[0108] The beneficial technical effects corresponding to the exemplary embodiments of this device can be found in the corresponding beneficial technical effects of the exemplary method section above, and will not be repeated here.

[0109] Exemplary electronic devices Figure 8 The present disclosure provides a structural diagram of an electronic device, which includes at least one processor 111 and a memory 112.

[0110] The processor 111 may be a central processing unit (CPU) or other form of processing unit with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device 11 to perform desired functions.

[0111] The memory 112 may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, etc. One or more computer program instructions may be stored on the computer-readable storage medium, and the processor 111 may execute one or more computer program instructions to implement the fire-storage combined frequency modulation method and / or other desired functions of the various embodiments of this disclosure described above.

[0112] In one example, the electronic device 11 may also include an input device 113 and an output device 114, which are interconnected via a bus system and / or other forms of connection mechanism (not shown).

[0113] The input device 113 may also include, for example, a keyboard, a mouse, etc.

[0114] The output device 114 can output various information to the outside, including, for example, a display, a speaker, a printer, and a communication network and its connected remote output devices, etc.

[0115] Of course, for the sake of simplicity, Figure 8 Only some of the components of the electronic device 11 relevant to this disclosure are shown, omitting components such as buses, input / output interfaces, etc. In addition, the electronic device 11 may include any other suitable components depending on the specific application.

[0116] Exemplary computer program products and computer-readable storage media In addition to the methods and apparatus described above, embodiments of this disclosure may also provide a computer program product, including computer program instructions that, when executed by a processor, cause the processor to perform the steps in the combined fire-storage frequency modulation method of the various embodiments of this disclosure described in the "Exemplary Methods" section above.

[0117] Computer program products can be written in any combination of one or more programming languages ​​to perform the operations of embodiments of this disclosure. These programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on a user's computing device, partially on a user's computing device, as a standalone software package, partially on a user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0118] Furthermore, embodiments of this disclosure may also be computer-readable storage media storing computer program instructions thereon, which, when executed by a processor, cause the processor to perform the steps in the combined fire-storage frequency modulation method of the various embodiments of this disclosure described in the "Exemplary Methods" section above.

[0119] Computer-readable storage media may take the form of any combination of one or more readable media. A readable medium may be a readable signal medium or a readable storage medium. A readable storage medium may include, but is not limited to, systems, apparatuses, or devices that are electrical, magnetic, optical, electromagnetic, infrared, or semiconductor, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: electrical connections having one or more wires, portable disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0120] The basic principles of this disclosure have been described above with reference to specific embodiments. However, the advantages, benefits, and effects mentioned in this disclosure are merely examples and not limitations, and should not be considered as essential features of each embodiment of this disclosure. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the scope of this disclosure to the necessity of employing the aforementioned specific details for implementation.

[0121] Various modifications and variations can be made to this disclosure without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this disclosure and their equivalents, this disclosure is also intended to include such modifications and variations.

Claims

1. A combined thermal and energy storage frequency regulation method, applied to an energy management system, characterized in that, The method includes: Receive the power grid frequency and determine the frequency deviation of the power grid frequency relative to the rated power grid frequency and the frequency change rate of the power grid frequency; When the frequency deviation and the frequency change rate meet the conditions for triggering a primary frequency regulation mode, the power command channel corresponding to the automatic generation control is set to a locked state. The power deviation amount corresponding to the automatic generation control adjustment command received during the locked state is stored in the power buffer queue according to the receiving time sequence. Based on the response speed differences of various energy storage devices in the energy storage system, frequency regulation power output tasks are allocated to the various energy storage devices at different time periods. If the conditions for ending the primary frequency regulation mode are met, the lockout state is released, and the real-time target power is obtained by superimposing the power deviation based on the reference power corresponding to the automatic power generation control. Based on the real-time target power, power commands are sent to the energy storage system and the thermal power generating unit. In the automatic power generation control mode, the real-time target power is used as the initial control point. The real-time target power is updated based on the absorption progress of the power buffer queue. Based on the updated real-time target power, energy storage output commands and thermal power output commands are generated and issued respectively, so that the total output power of the thermal-storage joint frequency regulation system tracks the real-time target power.

2. The method according to claim 1, characterized in that, After determining the frequency deviation of the power grid frequency relative to the rated power grid frequency and the rate of change of the power grid frequency, the method further includes: If the absolute value of the frequency deviation is greater than or equal to a first deviation threshold, and the duration for which the absolute value of the frequency deviation is greater than or equal to the first deviation threshold is greater than the dead time; or, The absolute value of the frequency change rate is greater than or equal to a change rate threshold, and the absolute value of the frequency deviation is greater than or equal to a second deviation threshold; wherein the second deviation threshold is less than the first deviation threshold. The current frequency modulation mode is determined to be the primary frequency modulation mode.

3. The method according to claim 1, characterized in that, The step of setting the power command channel corresponding to the automatic power generation control to a locked state, and storing the power deviation corresponding to the automatic power generation control adjustment command received during the locked state period into the power buffer queue according to the receiving time sequence, includes: Set the power command channel to the locked state, so that the energy storage system stops responding to the automatic power generation control and regulation command; The automatic power generation control adjustment command sent by the automatic power generation control system is acquired at a preset sampling period interval, and the automatic power generation control adjustment command is parsed into the power deviation amount; The power deviation is stored in the power cache queue in chronological order. During the duration of the lockout state, if the difference between the power command of the primary frequency regulation mode and the historical reference power of the automatic generation control exceeds the power limit of the energy storage system, then the power over-limit protection is triggered.

4. The method according to claim 1, characterized in that, The method of allocating frequency modulation power output tasks to various energy storage devices at different time periods based on the differences in response speeds within the energy storage system includes: In the initial stage of the first frequency regulation response, the first energy storage device in the energy storage system, which indicates the first response speed, outputs the first frequency regulation power. During the sustained phase following the initial phase, the second energy storage device in the energy storage system, which is instructed to have a second response speed, outputs a second frequency modulation power, and the first energy storage device is instructed to reduce the first frequency modulation power to a preset sustaining power at a preset derating rate. During a longer period following the sustained phase, the thermal power generating unit is instructed to output frequency-modulated power at a preset slow rate to coordinate with the second energy storage device.

5. The method according to claim 4, characterized in that, The method further includes: The ratio of the first rated power corresponding to the first energy storage device to the sum of the first rated power and the second rated power corresponding to the second energy storage device is within a preset range; wherein, the energy capacity of the first energy storage device is smaller than that of the second energy storage device; If the state of charge of the first energy storage device is lower than the first lower charge limit or higher than the first upper charge limit, the first energy storage device is instructed to reduce its output power to less than the first frequency modulation power; or... If the state of charge of the second energy storage device is lower than the second lower charge limit or higher than the second upper charge limit, the output power of the second energy storage device will be reduced to less than the second frequency modulation power. If the output power of the first energy storage device is less than the first frequency regulation power, or the output power of the second energy storage device is less than the second frequency regulation power, the total frequency regulation power deficit is calculated, and the thermal power generator set is controlled to supplement the total frequency regulation power deficit at a preset slow adjustment rate.

6. The method according to claim 1, characterized in that, When the conditions for ending the primary frequency regulation mode are met, the lockout state is released, and the real-time target power is obtained by superimposing the power deviation on the reference power corresponding to the automatic power generation control. Based on the real-time target power, power commands are then issued to the energy storage system and the thermal power generating unit, including: After the termination condition is met continuously for more than the recovery confirmation time, the lockout state of the automatic power generation control mode is released. With a preset rate of change as the upper limit, the power deviation in the power buffer queue is gradually retrieved, and the power deviation is added to the recovery reference power to obtain the real-time target power of the current automatic power generation control. The automatic power generation control system is instructed to resume issuing power commands to the energy storage system and the thermal power generating unit based on the real-time target power. If the retrieval execution time of the power cache queue exceeds a preset timeout threshold, the power cache queue is cleared and the reference power of the automatic generation control is recalculated based on the current grid frequency deviation.

7. The method according to claim 1, characterized in that, When the frequency modulation mode is the primary frequency modulation mode, the method further includes: Based on the deviation of the grid frequency from the rated frequency, the total power command for primary frequency regulation is calculated according to the preset frequency regulation characteristic coefficient; The primary frequency regulation total power command is used as the basis for allocating the frequency regulation power output tasks of the various energy storage devices, instructing the energy storage system to output frequency regulation power according to the allocation result; When the total available power of the energy storage system is less than the total power command of the primary frequency regulation, the thermal power generating unit supplements the power deficit at a preset slow rate.

8. A combined thermal power and energy storage frequency modulation device, characterized in that, include: The receiving module is configured to receive the power grid frequency and determine the frequency deviation of the power grid frequency relative to the rated power grid frequency and the frequency change rate of the power grid frequency. The allocation module is configured to, when the frequency deviation and the frequency change rate satisfy the triggering of the primary frequency regulation mode, set the power command channel corresponding to the automatic generation control to a locked state, store the power deviation amount corresponding to the automatic generation control adjustment command received during the locked state into the power buffer queue according to the receiving time sequence, and allocate frequency regulation power output tasks to the various energy storage devices at different time periods based on the response speed differences of various energy storage devices in the energy storage system. The recovery module is configured to release the lockout state when the primary frequency regulation mode termination condition is met, obtain the real-time target power by superimposing the power deviation based on the reference power corresponding to the automatic power generation control, and issue power commands to the energy storage system and thermal power generating unit based on the real-time target power. The control module is configured to, in the automatic power generation control mode, use the real-time target power as the initial control point, update the real-time target power based on the absorption progress of the power buffer queue, and generate and issue energy storage output commands and thermal power output commands based on the updated real-time target power, so that the total output power of the thermal-storage joint frequency regulation system tracks the real-time target power.

9. A computer-readable storage medium storing a computer program for performing the storage-coupled frequency modulation method according to any one of claims 1-7.

10. An electronic device, the electronic device comprising: processor; Memory used to store the processor's executable instructions; The processor is configured to read the executable instructions from the memory and execute the instructions to implement the memory-based frequency modulation method according to any one of claims 1-7.

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