A method and system for rapid frequency response in new energy power plants

Abstract

This invention relates to the field of new energy frequency regulation technology, and discloses a fast frequency response method and system for new energy power plants. The method obtains the grid frequency value of the new energy power plant. If the grid frequency value exceeds a preset primary frequency regulation dead zone, the power adjustment direction of the new energy power plant is determined based on the grid frequency value and the primary frequency regulation droop curve in which the new energy power plant participates. Based on the power adjustment direction, the corresponding power generation unit group for closed-loop control is determined, and the power target value of the new energy power plant is calculated. Based on the power target value, a fast discrete control adjustment method is used to allocate power to each power generation unit in the corresponding power generation unit group, obtaining a power allocation execution strategy. This strategy is then distributed to each power generation unit in the corresponding power generation unit group for frequency regulation response operations. This allows for frequency regulation response only to a portion of the power generation units, avoiding communication delays at the power plant and improving the start-up time and frequency response speed of the frequency regulation response.

Description

Technical Field

[0001] This invention relates to the field of new energy frequency regulation technology, and in particular to a fast frequency response method and system for new energy power stations. Background Technology

[0002] Frequency is a crucial indicator of power quality and a vital parameter reflecting the operating status of a power system. Generally, the system frequency reflects the basic balance between active power supply and demand in the power system, and it varies slowly within a small range with load fluctuations. Under stable operating conditions, generator output power remains balanced with system load and losses, and the power system frequency is at its nominal value. However, large-capacity loads, generator switching, and imperfect control equipment can all cause frequency deviations, thereby affecting the stable operation of the power system and the normal operation of user equipment. When power generation and user demand are unbalanced, and power consumption exceeds the generator's load capacity, resulting in low-frequency operation of the power grid, the rebalancing between power supply and load at low frequencies is very unstable, easily leading to grid collapse and seriously threatening the safe operation of the grid. Lower frequencies also cause a decrease in generator and motor speeds, resulting in reduced generator terminal voltage and motor output, thus affecting the quality and output of user products, increasing scrap rates for industrial users, and increasing the consumption of raw materials and energy. This can even lead to the burnout of power generation equipment and motors, as well as damage to other equipment. Automated equipment with strict frequency requirements often malfunctions, causing inaccurate clocks, increased errors in electrical measuring instruments, and malfunctions in automatic safety devices and relay protection. High-frequency operation of the power system refers to an abnormal operating condition where the system's power output exceeds the load's nominal frequency. This condition is mostly caused by power units suddenly shedding a large amount of load due to various reasons. When the power grid experiences high frequencies, it also poses significant hazards to the power system and users, especially in terms of safety.

[0003] Among them, new energy power stations include wind farms and photovoltaic power stations, which also need to participate in primary frequency regulation. The existing method is to control the power of all power generation units through the management system of the new energy power station to respond as required, such as controlling the power of all wind turbines or photovoltaic inverters. However, due to the large number of constituent units, wind farms / photovoltaic power stations are composed of dozens or hundreds of wind turbines / photovoltaic inverter units, and communication delays exist, making it difficult to improve their start-up time and frequency response speed. Summary of the Invention

[0004] This invention provides a method and system for rapid frequency response in new energy power plants, solving the technical problem of difficulty in improving the frequency response speed of new energy power plants.

[0005] In view of the above, the first aspect of the present invention provides a fast frequency response method for a new energy power station, wherein the new energy power station includes a first power generation unit group and a second power generation unit group, both of which contain multiple power generation units, wherein the output power of each power generation unit in the first power generation unit group is set to a minimum rated power limit, and the output power of each power generation unit in the second power generation unit group is set to a maximum rated power limit, the method comprising the following steps:

[0006] Obtain the grid frequency value of new energy power plants;

[0007] Determine whether the power grid frequency value exceeds the preset primary frequency regulation dead zone. If the power grid frequency value exceeds the preset primary frequency regulation dead zone, proceed to the next step.

[0008] The power adjustment direction of the new energy power station is determined based on the grid frequency value and the droop curve of the primary frequency regulation of the grid in which the new energy power station participates. The power adjustment direction includes increasing power and decreasing power.

[0009] The corresponding power generation unit group for closed-loop control is determined according to the power adjustment direction. If the power adjustment direction is increasing power, then the first power generation unit group is subjected to closed-loop control. If the power adjustment direction is decreasing power, then the second power generation unit group is subjected to closed-loop control.

[0010] Obtain the real-time active power of the new energy power station, and calculate the power target value of the new energy power station based on the power adjustment direction and the real-time active power;

[0011] Based on the power target value, the power is allocated to each power generation unit in the corresponding power generation unit group through a fast discrete control adjustment method to obtain the power allocation execution strategy.

[0012] The power allocation execution strategy is distributed to each power generation unit in the corresponding power generation unit group for frequency regulation response operation.

[0013] Preferably, the step of determining the power adjustment direction of the renewable energy power station based on the grid frequency value and the primary frequency regulation droop curve of the renewable energy power station, wherein the power adjustment direction includes increasing power and decreasing power, specifically includes:

[0014] The upper limit frequency and lower limit frequency of the primary frequency regulation operation zone are obtained from the primary frequency regulation droop curve of the power grid participating in the new energy power station.

[0015] The grid frequency value is compared with the upper limit frequency and the lower limit frequency of the primary frequency regulation zone. If the grid frequency value is greater than the upper limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be a decrease in power. If the grid frequency value is less than the lower limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be an increase in power.

[0016] Preferably, the step of obtaining the real-time active power of the renewable energy power station and calculating the power target value of the renewable energy power station based on the power adjustment direction and the real-time active power specifically includes:

[0017] Obtain the real-time active power of the renewable energy power station, denoted as P0, and use the following formula to determine the target power value of the renewable energy power station:

[0018]

[0019] In the formula, P* represents the power target value, δ represents the primary frequency regulation droop coefficient of new energy, and P N This represents the rated power, and f represents the grid frequency. d Indicates the first frequency modulation dead zone, f N This indicates the rated frequency of the power grid.

[0020] Preferably, the step of allocating power to each power generation unit in the corresponding power generation unit group according to the power target value using a fast discrete control adjustment method to obtain the power allocation execution strategy specifically includes:

[0021] Obtain the real-time power of the power generation unit group, denoted as P;

[0022] The power deviation is calculated based on the real-time power of the power generation unit group and the target power value.

[0023] ΔP=P*-P

[0024] In the formula, ΔP represents the power deviation;

[0025] The corresponding power distribution coefficient is calculated based on the power deviation using the following formula:

[0026]

[0027] In the formula, KP n K represents the power distribution factor. n Indicates the overshoot coefficient;

[0028] The power allocation value of the corresponding power generation unit is calculated using the power allocation coefficient.

[0029]

[0030] In the formula, Indicates the power allocation value;

[0031] The average response lag time of the power generation unit group is obtained. Based on the average response lag time of the power generation unit group, the command issuance interval is calculated using the following formula:

[0032]

[0033] In the formula, t0 represents the interval between command issuances and the average response lag time of the power generation unit group.

[0034] A power allocation execution strategy is formed based on the instruction issuance interval and the power allocation value corresponding to each power generation unit.

[0035] Preferably, after the step of distributing the power allocation execution strategy to each power generation unit in the corresponding power generation unit group for frequency regulation response operation, the method further includes:

[0036] Obtain the actual power value of the power grid after frequency regulation response operation at the new energy power station;

[0037] The actual power deviation is calculated based on the actual power value and the target power value. It is then determined whether the actual power deviation is greater than a preset deviation value. If the actual power deviation is greater than the preset deviation value, the overshoot coefficient is readjusted, and the corresponding power allocation coefficient is calculated based on the power deviation of each power generation unit using the following formula. If the actual power deviation is not greater than the preset deviation value, the frequency modulation operation ends.

[0038] Secondly, the present invention provides a rapid frequency response system for a new energy power station, wherein the new energy power station includes a first power generation unit group and a second power generation unit group, both of which contain multiple power generation units. The output power of each power generation unit in the first power generation unit group is set to a minimum rated power limit, and the output power of each power generation unit in the second power generation unit group is set to a maximum rated power limit. The system includes:

[0039] The frequency acquisition module is used to acquire the grid frequency value of new energy power plants;

[0040] The first judgment module is used to determine whether the power grid frequency value exceeds the preset primary frequency regulation dead zone;

[0041] The adjustment direction determination module is used to determine the power adjustment direction of the new energy power station based on the grid frequency value and the droop curve of the primary frequency regulation of the grid in which the new energy power station participates. The power adjustment direction includes increasing power and decreasing power.

[0042] A closed-loop control module is used to determine the power generation unit group corresponding to the closed-loop control according to the power adjustment direction. If the power adjustment direction is increasing power, then the first power generation unit group is subjected to closed-loop control; if the power adjustment direction is decreasing power, then the second power generation unit group is subjected to closed-loop control.

[0043] The target power calculation module is used to obtain the real-time active power of the new energy power station and calculate the target power value of the new energy power station based on the power adjustment direction and the real-time active power.

[0044] The frequency allocation module is used to allocate power to each power generation unit in the corresponding power generation unit group according to the power target value through a fast discrete control adjustment method, so as to obtain the power allocation execution strategy.

[0045] The frequency modulation response module is used to distribute the power allocation execution strategy to each power generation unit in the corresponding power generation unit group for frequency modulation response operation.

[0046] Preferably, the adjustment direction determination module specifically includes:

[0047] The limit acquisition module is used to obtain the upper limit frequency and the lower limit frequency of the primary frequency regulation operation zone based on the droop curve of the primary frequency regulation of the power grid in which the new energy power plants participate.

[0048] The direction determination module is used to compare the grid frequency value with the upper limit frequency and the lower limit frequency of the primary frequency regulation action zone, respectively. If the grid frequency value is greater than the upper limit frequency of the primary frequency regulation action zone, the power adjustment direction of the new energy power station is determined to be a decrease in power. If the grid frequency value is less than the lower limit frequency of the primary frequency regulation action zone, the power adjustment direction of the new energy power station is determined to be an increase in power.

[0049] Preferably, the target power calculation module specifically includes:

[0050] The active power acquisition module is used to acquire the real-time active power of the renewable energy power plant, denoted as P0. The target power value of the renewable energy power plant is obtained through the following formula:

[0051]

[0052] In the formula, P* represents the power target value, δ represents the primary frequency regulation droop coefficient of new energy, and P N This represents the rated power, and f represents the grid frequency. d Indicates the first frequency modulation dead zone, f N This indicates the rated frequency of the power grid.

[0053] Preferably, the frequency modulation allocation module specifically includes:

[0054] The unit power acquisition module is used to acquire the real-time power of the power generation unit group, denoted as P;

[0055] The deviation calculation module is used to calculate the power deviation based on the real-time power of the power generation unit group and the target power value.

[0056] ΔP=P*-P

[0057] In the formula, ΔP represents the power deviation;

[0058] The first coefficient calculation module is used to calculate the corresponding power allocation coefficient based on the power deviation using the following formula:

[0059]

[0060] In the formula, KP n K represents the power distribution factor. n Indicates the overshoot coefficient;

[0061] The power allocation calculation module is used to calculate the power allocation value of the corresponding power generation unit based on the power allocation coefficient.

[0062]

[0063] In the formula, Indicates the power allocation value;

[0064] The interval time calculation module is used to obtain the average response lag time of the power generation unit group, and calculates the command issuance interval time based on the average response lag time of the power generation unit group using the following formula:

[0065]

[0066] In the formula, t0 represents the interval between command issuances and the average response lag time of the power generation unit group.

[0067] The strategy construction module is used to form a power allocation execution strategy based on the instruction issuance interval and the power allocation value corresponding to each power generation unit.

[0068] Preferably, the system further includes:

[0069] The actual power acquisition module is used to acquire the actual power value of the power grid after frequency regulation response operation at the renewable energy power station;

[0070] The deviation comparison module is used to calculate the actual power deviation value based on the actual power value and the power target value, and determine whether the actual power deviation value is greater than a preset deviation value. If the actual power deviation value is greater than the preset deviation value, the overshoot coefficient is readjusted. If the actual power deviation value is not greater than the preset deviation value, the frequency modulation operation is terminated.

[0071] As can be seen from the above technical solutions, the present invention has the following advantages:

[0072] This invention obtains the grid frequency value of a new energy power station. If the grid frequency value exceeds the preset primary frequency regulation dead zone, the power adjustment direction of the new energy power station is determined based on the grid frequency value and the primary frequency regulation droop curve in which the new energy power station participates. Based on the power adjustment direction, the corresponding power generation unit group for closed-loop control is determined, and the power target value of the new energy power station is calculated. Based on the power target value, power is allocated to each power generation unit in the corresponding power generation unit group using a fast discrete control adjustment method to obtain a power allocation execution strategy. The power allocation execution strategy is then sent to each power generation unit in the corresponding power generation unit group to perform frequency regulation response operations. This allows frequency regulation response to be performed only on a portion of the power generation units, avoiding delays in power station communication and improving the start-up time and frequency response speed of the frequency regulation response. Attached Figure Description

[0073] Figure 1 A flowchart of a fast frequency response method for a new energy power station provided in an embodiment of the present invention;

[0074] Figure 2 This is a structural schematic diagram of a fast frequency response system for a new energy power station provided in an embodiment of the present invention. Detailed Implementation

[0075] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0076] For easier understanding, please refer to Figure 1 The present invention provides a fast frequency response method for a new energy power station, wherein the new energy power station includes a first power generation unit group and a second power generation unit group, both of which contain multiple power generation units. The output power of each power generation unit in the first power generation unit group is set to a minimum rated power limit, and the output power of each power generation unit in the second power generation unit group is set to a maximum rated power limit.

[0077] It should be noted that the proportion of generator units in the first and second power generation unit groups is not limited. In one example, the proportion of the first power generation unit group is 10% of all units. The power is set to the minimum; for example, in a wind farm, the power of the wind turbines is controlled to the minimum operating power without shutdown; in a photovoltaic power station, the power of the photovoltaic inverter modules is controlled to the minimum operating power without shutdown, typically 0, to leave sufficient room for power escalation in the commands. The proportion of the second power generation unit group depends on the requirements for rapid frequency regulation and the situation of the new energy power station; for example, the proportion of the second power generation unit group is 10% of all units. The power is set to the maximum power that can be generated. The remaining power generation units operate at normal power. Therefore, when the grid frequency changes, only the first or second power generation unit group needs to be controlled to achieve the goal of rapid frequency response.

[0078] The power generation unit refers to the wind turbine in a wind farm or the photovoltaic inverter in a photovoltaic power station. A wind farm uses dozens or even hundreds of wind power generation units to convert wind energy into electrical energy and transmit it to the power grid. When the wind speed is high, the wind turbine generates more power; when the wind speed is low, the wind turbine generates less power.

[0079] A photovoltaic power station uses dozens or even hundreds of photovoltaic inverter units to convert solar energy into electrical energy and transmit it to the power grid. When the sunlight is strong, the photovoltaic inverters generate more power; when the sunlight is weak, the photovoltaic inverters generate less power.

[0080] The method includes the following steps:

[0081] S1. Obtain the grid frequency value of the new energy power station;

[0082] S2. Determine whether the grid frequency value exceeds the preset primary frequency regulation dead zone. If the grid frequency value exceeds the preset primary frequency regulation dead zone, proceed to the next step.

[0083] In a typical example, the primary frequency dead zone is set to 0.05Hz.

[0084] S3. Determine the power adjustment direction of the new energy power station based on the grid frequency value and the primary frequency regulation droop curve of the new energy power station. The power adjustment direction includes increasing power and decreasing power.

[0085] S4. Determine the power generation unit group corresponding to the closed-loop control according to the power adjustment direction. If the power adjustment direction is increasing power, then the first power generation unit group is subject to closed-loop control. If the power adjustment direction is decreasing power, then the second power generation unit group is subject to closed-loop control.

[0086] S5. Obtain the real-time active power of the new energy power station, and calculate the power target value of the new energy power station based on the power adjustment direction and the real-time active power.

[0087] S6. Based on the power target value, power is allocated to each power generation unit in the corresponding power generation unit group using a fast discrete control adjustment method to obtain the power allocation execution strategy.

[0088] S7. Distribute the power allocation execution strategy to each power generation unit in the corresponding power generation unit group for frequency regulation response operation.

[0089] This embodiment provides a fast frequency response method for new energy power plants. By acquiring the grid frequency value of the new energy power plant, if the grid frequency value exceeds the preset primary frequency regulation dead zone, the power adjustment direction of the new energy power plant is determined based on the grid frequency value and the primary frequency regulation droop curve in which the new energy power plant participates. Based on the power adjustment direction, the corresponding power generation unit group for closed-loop control is determined, and the power target value of the new energy power plant is calculated. Based on the power target value, the power is allocated to each power generation unit in the corresponding power generation unit group through a fast discrete control adjustment method to obtain a power allocation execution strategy. The power allocation execution strategy is then sent to each power generation unit in the corresponding power generation unit group to perform frequency regulation response operations, thereby only performing frequency regulation response on some power generation units, avoiding delays in power plant communication, and improving the start time and frequency response speed of frequency regulation response.

[0090] In one specific embodiment, step S3 specifically includes:

[0091] S301. Obtain the upper limit frequency and lower limit frequency of the primary frequency regulation operation zone based on the droop curve of the primary frequency regulation of the power grid in which new energy power plants participate.

[0092] S302. Compare the grid frequency value with the upper limit frequency and the lower limit frequency of the primary frequency regulation zone, respectively. If the grid frequency value is greater than the upper limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be decreasing power. If the grid frequency value is less than the lower limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be increasing power.

[0093] In one specific embodiment, step S5 specifically includes:

[0094] S501. Obtain the real-time active power of the renewable energy power station, denoted as P0. The target power value of the renewable energy power station is obtained through the following formula:

[0095]

[0096] In the formula, P* represents the power target value, δ represents the primary frequency regulation droop coefficient of new energy, and P NThis represents the rated power, and f represents the grid frequency. d Indicates the first frequency modulation dead zone, f N This indicates the rated frequency of the power grid.

[0097] In one example, the differential coefficient is set to 5%, and the maximum power limit for primary frequency modulation is set to 6%. N The maximum power limit for frequency modulation is set to 10% P. N Where, when increased power is required, then ff d If it is a negative value, then ff is used when power needs to be reduced. d It is a positive value.

[0098] In one specific embodiment, step S6 specifically includes:

[0099] S601. Obtain the real-time power of the power generation unit group, denoted as P;

[0100] S602. Calculate the power deviation based on the real-time power of the power generation unit group and the target power value.

[0101] ΔP=P*-P

[0102] In the formula, ΔP represents the power deviation;

[0103] S603. The corresponding power distribution coefficient is calculated based on the power deviation using the following formula:

[0104]

[0105] In the formula, KP n K represents the power distribution factor. n Indicates the overshoot coefficient;

[0106] The overshoot coefficient is typically set to 1.2 to 2.

[0107] S604. Calculate the power allocation value of the corresponding power generation unit using the power allocation factor.

[0108]

[0109] In the formula, Indicates the power allocation value;

[0110] S605. Obtain the average response lag time of the power generation unit group, and calculate the command issuance interval time based on the average response lag time of the power generation unit group using the following formula.

[0111]

[0112] In the formula, t0 represents the interval between command issuances and the average response lag time of the power generation unit group.

[0113] The instruction issuance interval is used to represent the interval between each power generation unit's response to the instruction. Faster measurement response helps the power system's power supply to adjust quickly according to the grid frequency, thereby improving the grid's frequency stability.

[0114] S607. A power allocation execution strategy is formed based on the instruction issuance interval and the power allocation value corresponding to each power generation unit.

[0115] In one specific embodiment, step S7 is followed by:

[0116] S8. Obtain the actual power value of the power grid after frequency regulation response operation of the new energy power station;

[0117] S9. Calculate the actual power deviation value based on the actual power value and the power target value, and determine whether the actual power deviation value is greater than the preset deviation value. If the actual power deviation value is greater than the preset deviation value, readjust the overshoot coefficient and execute step S603. If the actual power deviation value is not greater than the preset deviation value, end the frequency modulation operation.

[0118] The above is a detailed description of an embodiment of a fast frequency response method for a new energy power station provided by the present invention. The following is a detailed description of an embodiment of a fast frequency response system for a new energy power station provided by the present invention.

[0119] For easier understanding, please refer to Figure 2 This invention provides a fast frequency response system for a new energy power station, wherein the new energy power station includes a first power generation unit group and a second power generation unit group, each containing multiple power generation units. The output power of each power generation unit in the first power generation unit group is set to a minimum rated power limit, and the output power of each power generation unit in the second power generation unit group is set to a maximum rated power limit. The system includes:

[0120] Frequency acquisition module 100 is used to acquire the grid frequency value of new energy power plants;

[0121] The first judgment module 200 is used to determine whether the power grid frequency value exceeds the preset primary frequency regulation dead zone;

[0122] The adjustment direction judgment module 300 is used to determine the power adjustment direction of the new energy power station based on the grid frequency value and the droop curve of the primary frequency regulation of the grid in which the new energy power station participates. The power adjustment direction includes increasing power and decreasing power.

[0123] The closed-loop control module 400 is used to determine the corresponding power generation unit group for closed-loop control based on the power adjustment direction. If the power adjustment direction is increasing power, then the first power generation unit group is subjected to closed-loop control; if the power adjustment direction is decreasing power, then the second power generation unit group is subjected to closed-loop control.

[0124] The target power calculation module 500 is used to obtain the real-time active power of the new energy power station and calculate the power target value of the new energy power station based on the power adjustment direction and the real-time active power.

[0125] The frequency allocation module 600 is used to allocate power to each power generation unit in the corresponding power generation unit group according to the power target value through a fast discrete control adjustment method, so as to obtain the power allocation execution strategy.

[0126] The frequency regulation response module 700 is used to distribute the power allocation execution strategy to each power generation unit in the corresponding power generation unit group for frequency regulation response operation.

[0127] In one specific embodiment, the direction determination module specifically includes:

[0128] The limit acquisition module is used to obtain the upper limit frequency and the lower limit frequency of the primary frequency regulation operation zone based on the droop curve of the primary frequency regulation of the power grid in which the new energy power plants participate.

[0129] The direction determination module compares the grid frequency value with the upper limit frequency and the lower limit frequency of the primary frequency regulation zone, respectively. If the grid frequency value is greater than the upper limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be decreasing power. If the grid frequency value is less than the lower limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be increasing power.

[0130] In one specific embodiment, the target power calculation module specifically includes:

[0131] The active power acquisition module is used to acquire the real-time active power of the renewable energy power plant, denoted as P0. The target power value of the renewable energy power plant is obtained through the following formula:

[0132]

[0133] In the formula, P* represents the power target value, δ represents the primary frequency regulation droop coefficient of new energy, and P N This represents the rated power, and f represents the grid frequency. d Indicates the first frequency modulation dead zone, f N This indicates the rated frequency of the power grid.

[0134] In one specific embodiment, the frequency modulation allocation module specifically includes:

[0135] The unit power acquisition module is used to acquire the real-time power of the power generation unit group, denoted as P;

[0136] The deviation calculation module is used to calculate the power deviation based on the real-time power of the power generation unit group and the target power value.

[0137] ΔP=P*-P

[0138] In the formula, ΔP represents the power deviation;

[0139] The first coefficient calculation module is used to calculate the corresponding power allocation coefficient based on the power deviation using the following formula:

[0140]

[0141] In the formula, KP n K represents the power distribution factor. n Indicates the overshoot coefficient;

[0142] The power allocation calculation module is used to calculate the power allocation value of the corresponding power generation unit based on the power allocation coefficient.

[0143]

[0144] In the formula, Indicates the power allocation value;

[0145] The interval time calculation module is used to obtain the average response lag time of the power generation unit group, and calculates the command issuance interval time based on the average response lag time of the power generation unit group using the following formula:

[0146]

[0147] In the formula, t0 represents the interval between command issuances and the average response lag time of the power generation unit group.

[0148] The strategy construction module is used to form a power allocation execution strategy based on the instruction issuance interval and the power allocation value corresponding to each power generation unit.

[0149] In one specific embodiment, the system further includes:

[0150] The actual power acquisition module is used to acquire the actual power value of the power grid after frequency regulation response operation at the renewable energy power station;

[0151] The deviation comparison module is used to calculate the actual power deviation value based on the actual power value and the power target value, and to determine whether the actual power deviation value is greater than the preset deviation value. If the actual power deviation value is greater than the preset deviation value, the overshoot coefficient is readjusted. If the actual power deviation value is not greater than the preset deviation value, the frequency modulation operation is terminated.

[0152] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0153] In the several embodiments provided by this invention, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0154] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0155] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0156] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fast frequency response method for new energy power stations, characterized in that, in, The new energy power station includes a first power generation unit group and a second power generation unit group. Both the first and second power generation unit groups contain multiple power generation units. The output power of each power generation unit in the first power generation unit group is set to a minimum rated power limit, and the output power of each power generation unit in the second power generation unit group is set to a maximum rated power limit. The method includes the following steps: Obtain the grid frequency value of new energy power plants; Determine whether the power grid frequency value exceeds the preset primary frequency regulation dead zone. If the power grid frequency value exceeds the preset primary frequency regulation dead zone, proceed to the next step. The power adjustment direction of the new energy power station is determined based on the grid frequency value and the droop curve of the primary frequency regulation of the grid in which the new energy power station participates. The power adjustment direction includes increasing power and decreasing power. The corresponding power generation unit group for closed-loop control is determined according to the power adjustment direction. If the power adjustment direction is increasing power, then the first power generation unit group is subjected to closed-loop control. If the power adjustment direction is decreasing power, then the second power generation unit group is subjected to closed-loop control. Obtain the real-time active power of the new energy power station, and calculate the power target value of the new energy power station based on the power adjustment direction and the real-time active power; Based on the power target value, a fast discrete control adjustment method is used to allocate power to each power generation unit in the corresponding power generation unit group, resulting in a power allocation execution strategy, including: Obtain the real-time power of the power generation unit group, denoted as P; The power deviation is calculated based on the real-time power of the power generation unit group and the target power value. ΔP=P*-P In the formula, ΔP represents the power deviation; The corresponding power distribution coefficient is calculated based on the power deviation using the following formula: In the formula, KP n K represents the power distribution factor. n Indicates the overshoot coefficient; The power allocation value of the corresponding power generation unit is calculated using the power allocation coefficient. In the formula, Indicates the power allocation value; The average response lag time of the power generation unit group is obtained. Based on the average response lag time of the power generation unit group, the command issuance interval is calculated using the following formula: In the formula, t0 represents the interval between command issuances and the average response lag time of the power generation unit group. A power allocation execution strategy is formed based on the instruction issuance interval and the power allocation value corresponding to each power generation unit. The power allocation execution strategy is distributed to each power generation unit in the corresponding power generation unit group for frequency regulation response operation.

2. The fast frequency response method for new energy power stations according to claim 1, characterized in that, The power adjustment direction of the renewable energy power plants is determined based on the grid frequency value and the primary frequency regulation droop curve of the power grid in which the renewable energy power plants participate. The power adjustment direction includes the steps of increasing power and decreasing power, specifically including: The upper limit frequency and lower limit frequency of the primary frequency regulation operation zone are obtained from the primary frequency regulation droop curve of the power grid participating in the new energy power station. The grid frequency value is compared with the upper limit frequency and the lower limit frequency of the primary frequency regulation zone. If the grid frequency value is greater than the upper limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be a decrease in power. If the grid frequency value is less than the lower limit frequency of the primary frequency regulation zone, the power adjustment direction of the new energy power station is determined to be an increase in power.

3. The fast frequency response method for new energy power stations according to claim 2, characterized in that, The steps of obtaining the real-time active power of the renewable energy power station and calculating the target power value of the renewable energy power station based on the power adjustment direction and the real-time active power specifically include: Obtain the real-time active power of the renewable energy power station, denoted as P0, and use the following formula to determine the target power value of the renewable energy power station: In the formula, P* represents the power target value, δ represents the primary frequency regulation droop coefficient of new energy, and P N This represents the rated power, and f represents the grid frequency. d Indicates the first frequency modulation dead zone, f N This indicates the rated frequency of the power grid.

4. The fast frequency response method for new energy power stations according to claim 1, characterized in that, After the step of distributing the power allocation execution strategy to each power generation unit in the corresponding power generation unit group for frequency regulation response, the method further includes: Obtain the actual power value of the power grid after frequency regulation response operation at the new energy power station; The actual power deviation is calculated based on the actual power value and the target power value. It is then determined whether the actual power deviation is greater than a preset deviation value. If the actual power deviation is greater than the preset deviation value, the overshoot coefficient is readjusted, and the corresponding power allocation coefficient is calculated based on the power deviation of each power generation unit using the following formula. If the actual power deviation is not greater than the preset deviation value, the frequency modulation operation ends.

5. A fast frequency response system for new energy power stations, characterized in that, in, The new energy power station includes a first power generation unit group and a second power generation unit group. Both groups contain multiple power generation units. The output power of each power generation unit in the first group is set to a minimum rated power limit, and the output power of each power generation unit in the second group is set to a maximum rated power limit. The system includes: The frequency acquisition module is used to acquire the grid frequency value of new energy power plants; The first judgment module is used to determine whether the power grid frequency value exceeds the preset primary frequency regulation dead zone; The adjustment direction determination module is used to determine the power adjustment direction of the new energy power station based on the grid frequency value and the droop curve of the primary frequency regulation of the grid in which the new energy power station participates. The power adjustment direction includes increasing power and decreasing power. A closed-loop control module is used to determine the power generation unit group corresponding to the closed-loop control according to the power adjustment direction. If the power adjustment direction is increasing power, then the first power generation unit group is subjected to closed-loop control; if the power adjustment direction is decreasing power, then the second power generation unit group is subjected to closed-loop control. The target power calculation module is used to obtain the real-time active power of the new energy power station and calculate the target power value of the new energy power station based on the power adjustment direction and the real-time active power. The frequency allocation module is used to allocate power to each power generation unit in the corresponding power generation unit group according to the power target value through a fast discrete control adjustment method, so as to obtain the power allocation execution strategy. The frequency modulation allocation module specifically includes: The unit power acquisition module is used to acquire the real-time power of the power generation unit group, denoted as P; The deviation calculation module is used to calculate the power deviation based on the real-time power of the power generation unit group and the target power value. ΔP=P*-P In the formula, ΔP represents the power deviation; The first coefficient calculation module is used to calculate the corresponding power allocation coefficient based on the power deviation using the following formula: In the formula, KP n K represents the power distribution factor. n Indicates the overshoot coefficient; The power allocation calculation module is used to calculate the power allocation value of the corresponding power generation unit based on the power allocation coefficient. In the formula, Indicates the power allocation value; The interval time calculation module is used to obtain the average response lag time of the power generation unit group, and calculates the command issuance interval time based on the average response lag time of the power generation unit group using the following formula: In the formula, t0 represents the interval between command issuances and the average response lag time of the power generation unit group. The strategy construction module is used to form a power allocation execution strategy based on the instruction issuance interval and the power allocation value corresponding to each power generation unit. The frequency modulation response module is used to distribute the power allocation execution strategy to each power generation unit in the corresponding power generation unit group for frequency modulation response operation.

6. The rapid frequency response system for new energy power stations according to claim 5, characterized in that, The adjustment direction determination module specifically includes: The limit acquisition module is used to obtain the upper limit frequency and the lower limit frequency of the primary frequency regulation operation zone based on the droop curve of the primary frequency regulation of the power grid in which the new energy power plants participate. The direction determination module is used to compare the grid frequency value with the upper limit frequency and the lower limit frequency of the primary frequency regulation action zone, respectively. If the grid frequency value is greater than the upper limit frequency of the primary frequency regulation action zone, the power adjustment direction of the new energy power station is determined to be a decrease in power. If the grid frequency value is less than the lower limit frequency of the primary frequency regulation action zone, the power adjustment direction of the new energy power station is determined to be an increase in power.

7. The rapid frequency response system for new energy power stations according to claim 6, characterized in that, The target power calculation module specifically includes: The active power acquisition module is used to acquire the real-time active power of the renewable energy power plant, denoted as P0. The target power value of the renewable energy power plant is obtained through the following formula: In the formula, P* represents the power target value, δ represents the primary frequency regulation droop coefficient of new energy, and P N This represents the rated power, and f represents the grid frequency. d Indicates the first frequency modulation dead zone, f N This indicates the rated frequency of the power grid.

8. The rapid frequency response system for new energy power stations according to claim 5, characterized in that, Also includes: The actual power acquisition module is used to acquire the actual power value of the power grid after frequency regulation response operation at the renewable energy power station; The deviation comparison module is used to calculate the actual power deviation value based on the actual power value and the power target value, and determine whether the actual power deviation value is greater than a preset deviation value. If the actual power deviation value is greater than the preset deviation value, the overshoot coefficient is readjusted. If the actual power deviation value is not greater than the preset deviation value, the frequency modulation operation is terminated.

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