Active support control method and system for hybrid new energy station of following construction network

Abstract

The invention discloses an active support control method and system for a follow-up network hybrid new energy station, and the method comprises the steps: collecting the operation state data of a high-voltage side of a grid-connected point of the new energy station, and calculating the short-circuit ratio of the new energy station; according to the station short-circuit ratio, switching an operation mode of a unit with a network following / constructing power generation mode; obtaining the active margin of each unit, calculating the active increment of the primary frequency modulation of the whole field, and carrying out the distribution according to the obtained active margin of the network tracking / constructing unit; calculating a full-field inertia frequency modulation active increment, judging an autonomous inertia supporting effect of the network-building type unit according to an active margin of the network-building type unit, and coordinating with the network-building type unit to jointly complete inertia frequency modulation; the reactive power margin of each unit is obtained, the autonomous voltage regulation supporting effect of the network-building type unit is judged according to the reactive power margin of the network-building type unit, and the network-building type unit is coordinated to carry out residual reactive power distribution according to the reactive power margin, so that economical and efficient cooperative operation of the hybrid new energy station and friendly power grid is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of renewable energy power generation research, and in particular to an active support control method and system for a hybrid renewable energy station. Background Art

[0002] Grid-following and grid-building technologies are two popular grid-connected control technologies in the current new energy industry. Grid-following technology uses phase-locked synchronization to control the output current of the converter. It is more mature, has more product types and lower costs. It is the mainstream grid-connected control technology in the current new energy industry. It has higher dynamic performance and stronger stability under strong power grids, but does not have the ability to actively support frequency and voltage, and it is difficult to operate stably under weak power grids. Grid-building technology does not use PLL for grid synchronization, but uses power self-synchronization control. Under weak power grid conditions, the grid-building type has strong support for grid frequency and voltage, large control stability margin, and can be separated from the large power grid and independently networked and operated. It has developed rapidly in recent years. At the same time, the grid-building type grid-connected control has slow power response under weak power grids, making it difficult to accurately achieve maximum power point tracking, poor economy, and the risk of low-frequency oscillation under high power grid strength. The power immunity between multiple machines is poor and the coupling is strong. It can be seen that hybrid grid-following / grid-building is an important networking form of future power grids, and hybrid new energy stations are important members of future new energy stations.

[0003] During operation, hybrid stations have a series of problems such as switching logic with the grid when the grid strength fluctuates greatly, coordination of active support regulation, and poor synchronization due to the strong autonomy of the grid-forming units, which seriously affect the stable operation of the grid. Summary of the invention

[0004] In view of the above existing problems, the present invention is proposed.

[0005] Therefore, the present invention provides an active support control method and system for a hybrid new energy station following a grid, which solves the problem of poor synchronization caused by the switching logic between the following grid type and the grid-building type grid-connected technologies of the hybrid new energy station when the grid strength fluctuates greatly, the coordination of the active support adjustment amount, and the autonomy of the grid-building type units.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] In the first aspect, the present invention provides an active support control method for a hybrid new energy station with a grid connection, including: collecting operating status data on the high-voltage side of the grid connection point of the new energy station, and calculating the short-circuit ratio of the new energy station based on the operating status data; switching the operating mode of the unit with a grid connection / grid connection mode according to the short-circuit ratio of the new energy station; obtaining the active margin and reactive margin of each unit based on the operating status of the unit; when the frequency on the high-voltage side of the grid connection point of the new energy station exceeds the set frequency dead zone range, calculating a frequency of the new energy station The secondary frequency regulation active power target value is distributed equally among the units according to the active margin and the primary frequency regulation active power target value of the new energy station; the autonomous inertia support effect of the grid-forming type units is judged according to the active margin of the grid-forming type units, and the grid-following type units are coordinated to distribute the remaining active power according to the active margin, and the inertia frequency regulation is jointly completed; the autonomous voltage regulation support effect of the grid-forming type units is judged according to the reactive margin of the grid-forming type units, and the grid-following type units are coordinated to distribute the remaining reactive power according to the reactive margin, and the reactive target value is jointly implemented.

[0008] As a preferred solution of the active support control method of the hybrid grid-following new energy station described in the present invention, wherein: according to the short-circuit ratio of the new energy station, switching the operation mode of the unit with the grid-following / grid-following power generation mode includes:

[0009] Collect the frequency, voltage, active power value, reactive power value and system impedance of the high-voltage side of the grid connection point of the new energy station. The system impedance is the impedance of the internal step-up transformer and internal lines of the station, and the impedance of the lines from the grid connection point of the station to the key nodes of the power grid;

[0010] The short-circuit ratio of the new energy station is calculated based on the collected no-load operating voltage before the new energy is connected to the grid, the nominal voltage of the new energy grid connection point, the voltage change caused by the new energy grid connection, the reactive power change during the operation of the new energy, the grid connection voltage change during the operation of the new energy, and the impedance value between the key nodes. The formula is expressed as follows:

[0011]

[0012] Among them, OSCR is the short-circuit ratio of the new energy station calculated online, U N is the rated system voltage at the grid connection point, It is the open circuit voltage of the grid connection point before the new energy is connected to the grid. is the voltage change caused by the connection of new energy to the grid, The voltage at the grid connection point of the new energy station;

[0013] Comparing the short-circuit ratio of the new energy station with the critical short-circuit ratio of system stability;

[0014] When the short-circuit ratio of the new energy station is less than the critical short-circuit ratio for stability of the system, the operating mode of the unit with the following / grid-building power generation mode will be switched to the grid-building mode; when the short-circuit ratio of the new energy station recovers to the stable operating short-circuit ratio, the operating mode of the unit with the following / grid-building power generation mode will be switched to the following mode.

[0015] As a preferred solution of the active support control method of the hybrid new energy station with a grid-connected structure described in the present invention, obtaining the active margin of each unit includes:

[0016] The upper adjustment active power margin of the wind turbine generator set is expressed as follows under the condition of unlimited power:

[0017]

[0018] The power limit regulation is expressed as:

[0019]

[0020] in, K is the effective capacity of wind turbines. s is the fan rotor kinetic energy utilization coefficient, E is the kinetic energy stored in the fan rotor, J is the fan rotational inertia, ω is the rotor speed, To adjust the effective capacity of wind turbines, The load reduction for wind turbines is is the output power of the wind turbine during maximum wind power tracking;

[0021] The downward adjustment active power margin of the wind turbine is expressed as:

[0022]

[0023] in, To adjust the wind turbines to lower their functional capacity, The current active power of the fan, It is the minimum output power for stable operation of the fan;

[0024] The active margin of the photovoltaic unit is 0 under unlimited power regulation and is expressed as:

[0025]

[0026] in, To adjust the functional capacity of photovoltaic units, The load reduction for photovoltaic units is is the output power of the photovoltaic unit during maximum light power tracking;

[0027] The active power margin of the photovoltaic unit is expressed as:

[0028]

[0029] in, To adjust the photovoltaic unit to have functional capacity, The current active power of the PV inverter, It is the minimum output power for stable operation of the photovoltaic unit.

[0030] As a preferred solution of the active support control method of the hybrid new energy station with a grid connection according to the present invention, obtaining the reactive power margin of each unit includes:

[0031] The reactive capacity range of the doubly-fed wind turbine generator system is expressed as:

[0032]

[0033] Among them, U S is the stator voltage, X S is the stator reactance, X m is the excitation impedance, I rmax is the maximum rotor current, P S is the stator active power, S C is the apparent power of the wind power converter, s is the slip rate, Q gmax is the maximum reactive power of the doubly-fed wind turbine, Q gmin is the minimum reactive capacity of the doubly-fed wind turbine generator set;

[0034] The reactive capacity range of full-power wind turbines is expressed as:

[0035]

[0036] Among them, U g is the grid voltage, U c is the grid-side voltage of the grid-side converter, X is the grid-side voltage of the grid-side converter, P is the output active power of the wind power converter, Q Smax is the maximum powerless capacity of the full-power wind turbine, Q Smin It is the minimum dead capacity of full-power wind turbine;

[0037] The reactive power range of a photovoltaic inverter is expressed as:

[0038]

[0039] Among them, U is the inverter output voltage, I is the inverter output current, P is the inverter active power, λ max Maximum power factor, λ min is the minimum power factor, Q pmax is the maximum powerless capacity of the photovoltaic inverter, Q pmin It is the minimum non-functional capacity of the photovoltaic inverter.

[0040] As a preferred solution of the active support control method of the hybrid new energy station with a grid structure described in the present invention, the calculation of equal margin distribution among the units according to the active margin and the primary frequency modulation active power target value of the new energy station is:

[0041]

[0042] Among them, ΔP i is the primary frequency regulation active power instruction that the i-th unit needs to bear, ΔP t is the primary frequency regulation active power regulation at the current moment, P capi-inert is the remaining active power regulation capacity of the i-th unit after executing inertia frequency regulation, The remaining active power regulation capacity after inertia frequency regulation is performed for all grid-type units. It is the remaining active power regulation capability after inertia frequency regulation is performed for all grid-following units.

[0043] As a preferred solution of the active support control method of the hybrid new energy station with a network according to the present invention, the jointly completing inertia frequency modulation includes:

[0044] By obtaining the active power margin of each unit, the active power margin of the grid-connected unit and the active power target value of the station inertia frequency regulation are compared. When the frequency change rate on the high-voltage side of the grid-connected point exceeds the preset frequency change rate dead zone range, the station inertia frequency regulation active power target value during frequency disturbance is calculated based on the frequency change rate and active power value on the high-voltage side of the grid-connected point.

[0045] When the active power margin of the grid-forming unit meets the inertia frequency regulation requirements of the station, the grid-forming unit autonomously performs inertia frequency regulation;

[0046] When the active power margin of the grid-forming unit does not meet the inertia frequency regulation requirements of the station, the inertia frequency regulation action limit is sent to the grid-forming unit, and the grid-forming unit controls the active autonomous response amount not to exceed the frequency regulation action limit. At the same time, the grid-following units are coordinated to respond to the inertia instructions, and the remaining inertia frequency regulation active power target of the station is distributed equally among the grid-following units.

[0047] As a preferred solution of the active support control method of the hybrid new energy station of the grid-connected structure described in the present invention, the jointly executed reactive power target value includes:

[0048] By obtaining the reactive margin of each unit, the reactive margin of the grid-type unit and the reactive power target value of the station voltage regulation are compared, wherein, when the difference between the high-voltage side voltage of the grid-connected point and the preset voltage reference value exceeds the voltage dead zone range, the reactive power target value of the station voltage regulation when the system voltage is disturbed is calculated according to the short-circuit ratio of the new energy station, the high-voltage side voltage value of the grid-connected point, and the reactive value;

[0049] When the reactive power margin of the grid-forming unit meets the voltage regulation requirement of the station, the grid-forming unit autonomously performs voltage regulation;

[0050] When the reactive power margin of the grid-forming unit does not meet the voltage regulation requirement of the station, the reactive power limit of the voltage regulation action is sent to the grid-forming unit, and the grid-forming unit controls the autonomous reactive response amount not to exceed the reactive power limit of the voltage regulation action. At the same time, the grid-following units are coordinated to respond to the reactive power instruction of the voltage regulation, and the remaining voltage regulation reactive power target of the station is distributed equally among the grid-following units.

[0051] In a second aspect, the present invention provides a hybrid new energy station active support control system, including:

[0052] A collection and calculation module, used to collect the operating status data of the high-voltage side of the grid connection point of the new energy station, and calculate the short-circuit ratio of the new energy station based on the operating status data;

[0053] A grid-following switching module is used to switch the operation mode of the unit with grid-following / grid-following power generation mode according to the short-circuit ratio of the new energy station;

[0054] Active / reactive margin acquisition module, used to obtain active margin and reactive margin of each unit based on the unit operation status;

[0055] The active power distribution module is used to calculate the primary frequency regulation active power target value of the new energy station when the frequency of the high-voltage side of the grid connection point of the new energy station exceeds the set frequency dead zone range, and perform equal margin distribution among the units according to the active margin and the primary frequency regulation active power target value of the new energy station; judge the autonomous inertia support effect of the grid-forming unit according to the active margin of the grid-forming unit, and coordinate the grid-following unit to distribute the remaining active power according to the active margin, so as to jointly complete the inertia frequency regulation;

[0056] The reactive power distribution module is used to determine the autonomous voltage regulation support effect of the grid-forming units according to the reactive margin of the grid-forming units, and coordinate the distribution of the remaining reactive power of the grid-forming units according to the reactive margin, and jointly implement the reactive target value.

[0057] As a preferred solution of the active support control system of the hybrid new energy station with a network according to the present invention, the acquisition and calculation module includes:

[0058] The data acquisition module is used to collect the frequency, voltage, active value, reactive value and system impedance of the high-voltage side of the grid connection point of the new energy station. The system impedance is the impedance of the internal step-up transformer and internal line of the station, and the impedance of the line from the grid connection point of the station to the key nodes of the power grid;

[0059] The short-circuit ratio calculation module is used to calculate the short-circuit ratio of the new energy station based on the collected no-load operating voltage before the new energy is connected to the grid, the nominal voltage of the new energy grid connection point, the voltage change caused by the new energy grid connection, the reactive power change during the operation of the new energy, the grid connection voltage change during the operation of the new energy, and the impedance value between key nodes.

[0060] As a preferred solution of the active support control system of the hybrid new energy station with a network according to the present invention, the active power distribution module includes:

[0061] The first allocation module is used to calculate the primary frequency regulation active power target value of the new energy station when the frequency of the high-voltage side of the grid connection point of the new energy station exceeds the set frequency dead zone range, and perform equal margin allocation among the units according to the active power margin and the primary frequency regulation active power target value of the new energy station;

[0062] The first calculation module is used to obtain the active power margin of each unit and compare the active power margin of the grid-type unit with the target value of the inertia frequency modulation active power of the station. When the frequency change rate of the high-voltage side of the grid connection point exceeds the preset frequency change rate dead zone range, the target value of the inertia frequency modulation active power of the station during the frequency disturbance is calculated according to the frequency change rate and active power value of the high-voltage side of the grid connection point;

[0063] An inertia frequency regulation action module is used for the grid-forming type unit to autonomously perform inertia frequency regulation action when the active power margin of the grid-forming type unit meets the inertia frequency regulation requirements of the station;

[0064] The second allocation module is used to send an inertia frequency regulation action limit to the networking unit when the active margin of the networking unit does not meet the inertia frequency regulation requirements of the station, and the networking unit controls the active autonomous response amount not to exceed the frequency regulation action limit. At the same time, it coordinates the response of the grid-following unit to the inertia instruction, and distributes the remaining inertia frequency regulation active power target of the station with equal margin among the grid-following units.

[0065] As a preferred solution of the active support control system of the hybrid new energy station with a grid-connected network according to the present invention, the reactive power distribution module includes:

[0066] The second calculation module is used to obtain the reactive margin of each unit and compare the reactive margin of the grid-type unit with the reactive power target value of the station voltage regulation, wherein when the difference between the high-voltage side voltage of the grid-connected point and the preset voltage reference value exceeds the voltage dead zone range, the reactive power target value of the station voltage regulation when the system voltage is disturbed is calculated according to the short-circuit ratio of the new energy station, the high-voltage side voltage value of the grid-connected point, and the reactive value;

[0067] A voltage regulation action module, used for the grid-forming unit to autonomously perform voltage regulation when the reactive power margin of the grid-forming unit meets the voltage regulation requirement of the station;

[0068] The third allocation module is used to send the reactive power limit of the voltage regulation action to the networking unit when the reactive power margin of the networking unit does not meet the voltage regulation requirement of the station. The networking unit controls the reactive power autonomous response amount not to exceed the reactive power limit of the voltage regulation action, and coordinates the following network units to respond to the reactive power instruction of the voltage regulation, and distributes the remaining voltage regulation reactive power target of the station with equal margin among the following network units.

[0069] In a third aspect, the present invention provides a computing device, comprising:

[0070] Memory and processor;

[0071] The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the active support control method of the hybrid new energy station of the follow-up network are implemented.

[0072] In a fourth aspect, the present invention provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, can implement the steps of the active support control method for a hybrid new energy station with a network structure.

[0073] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention provides an active support control method and system for a hybrid new energy station with a following network. By dynamically identifying the short-circuit ratio of the new energy station, it provides a basis for adjusting the operation mode and active support parameters of a new energy unit with following / networking module switching, and formulates a frequency and voltage active support coordinated control strategy for the hybrid new energy station, thereby realizing the economical and efficient coordinated operation of the hybrid new energy station with a friendly grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0075] Figure 1 It is a schematic diagram of the overall process logic of the active support control method of the hybrid new energy station with a network according to an embodiment of the present invention;

[0076] Figure 2 It is a flow chart of real-time monitoring of the short-circuit ratio of a new energy station and switching between the following / building network operation modes of an active support control method for a hybrid new energy station of a following / building network according to an embodiment of the present invention;

[0077] Figure 3A flow chart of an active support control method for a hybrid new energy station with a grid connection according to an embodiment of the present invention for calculating active regulation quantities for inertia frequency regulation and primary frequency regulation in a hybrid station with a grid connection and for implementing active command distribution among units;

[0078] Figure 4 It is a flow chart of the active support control method for a hybrid new energy station with a grid connection according to an embodiment of the present invention, which calculates reactive regulation amount and realizes reactive command distribution among units in a hybrid station with a grid connection for rapid voltage regulation;

[0079] Figure 5 This is a schematic diagram of the overall configuration of an active support control system for a hybrid new energy station with a network / follow-up network according to an embodiment of the present invention. DETAILED DESCRIPTION

[0080] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0081] Example 1

[0082] Reference Figure 1-Figure 4 As an embodiment of the present invention, a method for active support control of a hybrid new energy station with a network is provided, such as Figure 1 The specific steps shown include:

[0083] S100: collecting the operating status data of the high-voltage side of the grid-connected point of the new energy station, and calculating the short-circuit ratio of the new energy station based on the operating status data of the high-voltage side of the grid-connected point of the new energy station;

[0084] S200: Compare the short-circuit ratio of the new energy station with the critical short-circuit ratio of system stability, and switch the operation mode of the unit with the grid-following / grid-building power generation mode according to the comparison result;

[0085] S300: When the difference between the high-voltage side voltage of the grid connection point and the preset voltage reference value exceeds the voltage dead zone range, the reactive power target value when the system voltage is disturbed is calculated according to the short-circuit ratio of the new energy station, the high-voltage side voltage value of the grid connection point, and the reactive value;

[0086] S400: When the frequency change rate of the high-voltage side of the grid connection point exceeds the preset frequency change rate dead zone range, the inertia frequency regulation active power target value of the new energy station during frequency disturbance is calculated according to the frequency change rate and active value of the high-voltage side of the grid connection point;

[0087] S500: Obtain the active power margin of each unit, and compare the active power margin of the grid-forming unit with the inertia frequency regulation active power target value; when the active power margin of the grid-forming unit meets the inertia frequency regulation requirements of the station, the grid-forming unit autonomously performs inertia frequency regulation; when the active power margin of the grid-forming unit does not meet the inertia frequency regulation requirements of the station, send the inertia frequency regulation action limit to the grid-forming unit, and the grid-forming unit controls the active power autonomous response amount not to exceed the frequency regulation action limit, and at the same time coordinates the response of the grid-following unit to the inertia instruction, and distributes the remaining inertia frequency regulation active power target of the station among the grid-following units with equal margin;

[0088] S600: When the frequency on the high-voltage side of the grid-connected point of the new energy station exceeds the set frequency dead zone range, the primary frequency regulation active power target value of the new energy station is calculated, and equal margin distribution is performed among the units according to the active margin obtained in real time and the primary frequency regulation active power target value of the new energy station;

[0089] S700: Obtain the reactive power margin of each unit, and compare the reactive power margin of the grid-forming unit with the reactive power target value of the station voltage regulation; when the reactive power margin of the grid-forming unit meets the voltage regulation requirements of the station, the grid-forming unit autonomously performs voltage regulation; when the reactive power margin of the grid-forming unit does not meet the voltage regulation requirements of the station, send the reactive power limit value of the voltage regulation action to the grid-forming unit, and the grid-forming unit controls the reactive power autonomous response amount not to exceed the reactive power limit value of the voltage regulation action, and at the same time coordinates the grid-following unit to respond to the reactive power instruction of the voltage regulation, and distributes the remaining reactive power target of the station with equal margin among the grid-following units;

[0090] It should be noted that the present invention provides an active support control method and system for a hybrid new energy station with a following network. By dynamically identifying the short-circuit ratio of the new energy station, a basis is provided for adjusting the operation mode and active support parameters of a new energy unit with following / networking module switching, and a frequency and voltage active support coordinated control strategy for the hybrid new energy station is formulated, thereby achieving economical and efficient coordinated operation of the hybrid new energy station with a friendly grid.

[0091] In the embodiment of the present application, the above step S100 includes the following sub-steps A1-A2;

[0092] In A1: collect the operating status data of the high-voltage side of the new energy station grid connection point;

[0093] In A2: the short-circuit ratio of the new energy station is calculated based on the operating status data of the high-voltage side of the new energy station grid connection point;

[0094] In an optional embodiment, the operating status data of the high voltage side of the new energy station grid connection point includes the frequency f of the high voltage side of the new energy station grid connection point. pcc , voltage U pcc , Active power value P of the grid connection point pcc, Reactive value Q of grid connection point pcc and system impedance, where the system impedance is the internal boost transformer impedance Z of the new energy station mt , Impedance Z of the internal line of the station li , the impedance Z of the line from the station connection point to the key node of the power grid ni ;

[0095] It should be noted that new energy stations are wind farms equipped with a certain proportion of converters with grid switching function or photovoltaic power stations equipped with a certain proportion of inverters with grid switching function.

[0096] In an optional embodiment, the short-circuit ratio of the new energy station is calculated based on the collected no-load operating voltage before the new energy grid is connected, the nominal voltage of the new energy grid connection point, the voltage change caused by the new energy grid connection, the reactive power change during the operation of the new energy, the grid connection voltage change during the operation of the new energy, and the impedance value between the key nodes. The formula is expressed as follows:

[0097]

[0098] Among them, OSCR is the short-circuit ratio of the new energy station calculated online, U N is the rated system voltage at the grid connection point, It is the open circuit voltage of the grid connection point before the new energy is connected to the grid. is the voltage change caused by the connection of new energy to the grid, It is the voltage at the grid connection point of the new energy station.

[0099] In the embodiment of the present application, the above step S200 is as follows Figure 2 The method includes the following sub-steps B1-B3;

[0100] In B1: compare the short-circuit ratio of the new energy station with the critical short-circuit ratio of system stability (usually configured as 2);

[0101] In B2: when the short-circuit ratio of the new energy station is less than the critical short-circuit ratio of system stability, the operation mode of the units with grid-following / grid-building generation mode will be switched to grid-building mode;

[0102] In B3: When the short-circuit ratio of the new energy station returns to the stable operating short-circuit ratio (usually configured as 2.2), the operating mode of the units with grid-following / grid-building power generation mode will be switched to the grid-following mode.

[0103] In an optional embodiment, the switching formula between the network building mode and the network following mode is expressed as:

[0104]

[0105] Among them, GF L-MThe flag position of the unit in the new energy station with the grid-following / grid-building power generation mode is switched from the grid-following mode to the grid-building mode. M-L It is a flag for the new energy station with the function of following / building the grid power generation mode, which switches from the building the grid mode to the following the grid mode. OSCR is the short-circuit ratio of the new energy station measured online. CSCR is the critical short-circuit ratio of the new energy station. SSCR is the short-circuit ratio of the new energy station in stable operation.

[0106] It should be noted that the above step S200 can intelligently switch the operation mode of the dual-mode generator set with grid-following and grid-building types by comparing the short-circuit ratio of the new energy station with the stable critical short-circuit ratio of the system, thereby optimizing the stability and dynamic response of the system under different grid strength conditions, and effectively improving the overall operation quality and reliability of the power grid; this dynamic switching mechanism not only enhances the adaptability of the system, but also can maximize the use of new energy resources and reduce the instability factors caused by changes in grid conditions.

[0107] In the embodiment of the present application, the above step S300: when the difference between the high-voltage side voltage of the grid connection point and the preset voltage reference value exceeds the voltage dead zone range, the reactive power target value when the system voltage is disturbed is calculated according to the short-circuit ratio of the new energy station, the high-voltage side voltage value of the grid connection point, and the reactive value;

[0108] In an optional embodiment, the calculation formula of the reactive power target value when the system voltage is disturbed is:

[0109]

[0110] Among them, ΔQ is the reactive power target value required for voltage regulation of the new energy station, OSCR is the short-circuit ratio of the station calculated online, Q t+1 , Q is the reactive power of the grid connection point after compensation and the voltage on the high-voltage side of the grid connection point. t , It is the reactive power and voltage of the grid connection point before compensation.

[0111] In the embodiment of the present application, the above step S400: when the frequency change rate of the high-voltage side of the grid connection point exceeds the preset frequency change rate dead zone range (49.95Hz~50.05Hz), the inertia frequency modulation active power target value of the new energy station during frequency disturbance is calculated according to the frequency change rate and active value of the high-voltage side of the grid connection point;

[0112] In an optional embodiment, the calculation of the inertia frequency modulation active power target value of the new energy station during frequency disturbance is:

[0113]

[0114] Among them, ΔP tis the active power target value required for inertia frequency regulation of new energy stations, T J is the equivalent inertia time constant of the new energy station, is the frequency change rate of the new energy station grid connection point, f N is the rated frequency of the power system, P t It is the real-time active power of new energy stations.

[0115] In the embodiment of the present application, the above step S500 is as follows Figure 3 The method includes the following sub-steps E1-E2;

[0116] In E1: obtain the active power margin of each unit;

[0117] In E2: compare the active power margin of the grid-forming units and the active power target value of the inertia frequency regulation;

[0118] In E3: When the active power margin of the grid-forming unit meets the inertia frequency regulation requirements of the station, the grid-forming unit will autonomously perform inertia frequency regulation;

[0119] In E4: When the active power margin of the grid-forming unit does not meet the inertia frequency regulation requirements of the station, the inertia frequency regulation action limit is sent to the grid-forming unit, and the grid-forming unit controls the active power autonomous response amount not to exceed the frequency regulation action limit. At the same time, the grid-following unit is coordinated to respond to the inertia instruction, and the remaining inertia frequency regulation active power target of the station is distributed equally among the grid-following units;

[0120] In an optional embodiment, obtaining the active power margin of each generator set includes:

[0121] The upper regulation active margin of the wind turbine generator set is expressed as follows under the condition of unlimited power:

[0122]

[0123] The power limit regulation is expressed as:

[0124]

[0125] in, K is the effective capacity of wind turbines. s is the fan rotor kinetic energy utilization coefficient, E is the kinetic energy stored in the fan rotor, J is the fan rotational inertia, ω is the rotor speed, To adjust the effective capacity of wind turbines, The load reduction of wind turbines is usually 10% to 20%. is the output power of the wind turbine during maximum wind power tracking;

[0126] The downward adjustment active power margin of the wind turbine is expressed as:

[0127]

[0128] in, To adjust the wind turbines to lower their functional capacity, The current active power of the fan, The minimum output power for stable operation of the fan, usually 10% to 20% of the rated power;

[0129] The active margin of the photovoltaic unit is 0 under unlimited power regulation and is expressed as:

[0130]

[0131] in, To adjust the functional capacity of photovoltaic units, The load reduction of the photovoltaic unit is usually 10% to 20%. is the output power of the photovoltaic unit during maximum light power tracking;

[0132] The active power margin of the photovoltaic unit is expressed as:

[0133]

[0134] in, To adjust the photovoltaic unit to have functional capacity, The current active power of the PV inverter, It is the minimum output power for stable operation of a photovoltaic system, usually 10% of the rated power.

[0135] In an optional embodiment, when the active power margin of the grid-forming unit meets the station inertia frequency regulation requirements, the formula is expressed as:

[0136]

[0137] In the formula, is the inertia frequency regulation active power limit that the i-th grid-type unit needs to bear, ΔP t is the active frequency regulation value of inertia at the current moment, P capi is the active power regulation capability of the i-th grid-type unit, It is the total active power regulation capability of all grid-type units.

[0138] In an optional embodiment, when the active power margin of the grid-forming unit does not meet the station inertia frequency regulation requirements, the formula is expressed as:

[0139]

[0140] In the formula, is the active limit of inertia frequency regulation that the i-th grid-type unit needs to bear, P capiis the active power regulation capability of the i-th grid-type unit, ΔP j is the inertia frequency regulation command value that the jth grid-following unit needs to bear, ΔP left In addition to the inertia frequency regulation active power borne by the grid-type units at the current moment, the active power regulation amount that needs to be borne by the grid-type units is calculated. It is the total active power regulation capability of all grid-connected units.

[0141] It should be noted that the above step S500 can realize intelligent frequency regulation allocation by comparing the active power margin of the grid-building type unit with the active power target value of the inertia frequency regulation. When the active power margin of the grid-building type unit is sufficient to meet the inertia frequency regulation requirements of the station, the unit can autonomously perform the inertia frequency regulation action; when the active power margin is insufficient, the autonomous response amount of the grid-building type unit is limited, and the remaining inertia frequency regulation requirements are supplemented by coordinating with the grid-following type unit, thereby ensuring the stability of the system frequency while improving the operational flexibility and reliability of the entire new energy station, effectively balancing the autonomy of the grid-building type unit and the coordination of the grid-following type unit, and improving the response capability and overall stability of the power grid in the face of frequency fluctuations.

[0142] In the embodiment of the present application, the above step S600: when the frequency on the high-voltage side of the grid connection point of the new energy station exceeds the set frequency dead zone range, the primary frequency regulation active power target value of the new energy station is calculated, and equal margin distribution is performed among the units according to the active margin obtained in real time and the primary frequency regulation active power target value of the new energy station;

[0143] In an optional embodiment, the calculation of the primary frequency modulation active power target value of the new energy station is:

[0144]

[0145] Where: ΔP t is the active power target value required for primary frequency regulation of the new energy station, K f is the primary frequency modulation active frequency modulation coefficient, Δf is the power system frequency deviation, f N is the rated frequency of the power system, P t It is the real-time active power of new energy stations.

[0146] In an optional embodiment, the calculation of equal margin distribution among the units based on the active margin obtained in real time and the primary frequency regulation active power target value of the new energy station is:

[0147]

[0148] Among them, ΔP i is the primary frequency regulation active power instruction that the i-th unit needs to bear, ΔP t is the primary frequency modulation active power regulation at the current moment, Pcapi-inert is the remaining active power regulation capacity of the i-th unit after executing inertia frequency regulation, The remaining active power regulation capacity after inertia frequency regulation is performed for all grid-type units. It is the remaining active power regulation capability after inertia frequency regulation is performed for all grid-following units.

[0149] It should be noted that the above step S600 can respond to changes in the frequency on the high-voltage side of the grid connection point in a timely manner, by calculating the active power target value required for the primary frequency regulation and reasonably allocating it according to the real-time active power margin of each unit, ensuring that when the frequency exceeds the set dead zone, the new energy station can quickly and effectively participate in the primary frequency regulation of the power grid and maintain the stability of the power grid frequency. It not only improves the speed and accuracy of the frequency regulation response, but also realizes load balancing between units through the equal margin allocation mechanism, thereby enhancing the stability and efficiency of the entire new energy station.

[0150] In the embodiment of the present application, the above step S700 is as follows Figure 4 The method includes the following sub-steps G1-G2;

[0151] In G1: obtain the reactive power margin of each unit;

[0152] In G2: compare the reactive power margin of grid-type units and the reactive power target value of station voltage regulation;

[0153] In G3: When the reactive power margin of the grid-forming unit meets the voltage regulation requirements of the station, the grid-forming unit will autonomously perform voltage regulation;

[0154] In G4: When the reactive power margin of the grid-forming unit does not meet the voltage regulation requirements of the station, the reactive power limit of the voltage regulation action is sent to the grid-forming unit, and the grid-forming unit controls the reactive power autonomous response amount not exceeding the reactive power limit of the voltage regulation action. At the same time, the grid-following unit is coordinated to respond to the voltage regulation reactive power instruction, and the remaining voltage regulation reactive power target of the station is distributed equally among the grid-following units;

[0155] In an optional embodiment, obtaining the reactive power margin of each generator set includes:

[0156] The reactive capacity range of the doubly-fed wind turbine generator system is expressed as:

[0157]

[0158] Among them, U S is the stator voltage, X S is the stator reactance, X m is the excitation impedance, I rmax is the maximum rotor current, P S is the stator active power, S C is the apparent power of the wind power converter, s is the slip rate, Q gmaxis the maximum reactive power of the doubly-fed wind turbine, Q gmin is the minimum reactive capacity of the doubly-fed wind turbine generator set;

[0159] The reactive capacity range of full-power wind turbines is expressed as:

[0160]

[0161] Among them, U g is the grid voltage, U c is the grid-side voltage of the grid-side converter, X is the grid-side voltage of the grid-side converter, P is the output active power of the wind power converter, Q Smax is the maximum powerless capacity of the full-power wind turbine, Q Smin It is the minimum dead capacity of full-power wind turbine;

[0162] The reactive power range of a photovoltaic inverter is expressed as:

[0163]

[0164] Among them, U is the inverter output voltage, I is the inverter output current, P is the inverter active power, λ max Maximum power factor, λ min is the minimum power factor, Q pmax is the maximum powerless capacity of the photovoltaic inverter, Q pmin It is the minimum powerless capacity of the photovoltaic inverter;

[0165] In the above units, the reactive power support capacity is:

[0166] Q capup =Q max -Q opt

[0167] Q capdown =Q opt -Q min

[0168] Among them, Q capup is the reactive power support capacity of the unit; Q capdown Q is the reactive power support capacity of the unit; max is the upper limit of reactive power of the unit; Q min The lower limit of reactive power of the unit; Q opt is the current reactive power of the unit.

[0169] In an optional embodiment, when the reactive power margin of the grid-type unit meets the voltage regulation requirements of the station, the formula is expressed as:

[0170]

[0171] in, is the reactive power limit of the rapid voltage regulation that the i-th grid-type unit needs to bear, ΔQ t Q is the reactive power regulation amount of rapid voltage regulation at the current moment, capi is the reactive power regulation capability of the i-th grid-type unit, is the total reactive power regulation capacity of all grid-connected units, ΔQ lossi is the reactive power loss value of the i-th grid-type unit.

[0172] In an optional embodiment, when the reactive power margin of the grid-type unit does not meet the voltage regulation requirements of the station, the formula is expressed as:

[0173]

[0174] in, is the reactive power limit of the rapid voltage regulation that the i-th grid-type unit needs to bear, Q capi is the reactive power regulation capability of the i-th grid-type unit, ΔQ j is the rapid voltage regulation command value that the jth grid-following unit needs to bear, ΔQ left In order to eliminate the rapid voltage regulation reactive power borne by the grid-type units at the current moment, the reactive power regulation amount that needs to be borne by the grid-type units is is the total reactive power regulation capacity of all grid-connected units, ΔQ lossj is the reactive power loss value of the jth grid-following unit.

[0175] It should be noted that the above step S700 realizes an intelligent voltage regulation strategy by comparing the reactive margin of the grid-type unit with the reactive power target value of the station voltage regulation. When the reactive margin of the grid-type unit is sufficient to meet the voltage regulation demand, the unit can autonomously perform the voltage regulation action; when the reactive margin is insufficient, the reactive response of the grid-type unit is limited, and the remaining voltage regulation demand is compensated by coordinating with the grid-following unit, thereby ensuring voltage stability while improving the operational flexibility and reliability of the entire new energy station, effectively balancing the autonomy of the grid-type unit and the coordination of the grid-following unit, and enhancing the responsiveness and overall stability of the power grid in the face of voltage fluctuations.

[0176] Example 2

[0177] Reference Figure 5 Another embodiment of the present invention provides a hybrid new energy station active support control system, including a collection and calculation module, a network switching module, an active / reactive margin acquisition module, an active power distribution module, and a reactive power distribution module;

[0178] Specifically, the collection and calculation module is used to collect the operating status data of the high-voltage side of the new energy station grid connection point, and calculate the short-circuit ratio of the new energy station based on the operating status data of the high-voltage side of the new energy station grid connection point;

[0179] Specifically, the grid-following switching module is used to switch the operation mode of the unit with grid-following / grid-following generation mode according to the short-circuit ratio of the new energy station;

[0180] Specifically, the active / reactive margin acquisition module is used to acquire the active margin and reactive margin of each unit based on the unit operation status;

[0181] Specifically, the active power distribution module is used to calculate the primary frequency regulation active power target value of the new energy station when the frequency on the high-voltage side of the grid connection point exceeds the set frequency dead zone range, and to distribute the active power between the units with equal margin according to the active margin and the primary frequency regulation active power target value of the new energy station; to judge the autonomous inertia support effect of the grid-forming unit according to the active margin of the grid-forming unit, and to coordinate the grid-following unit to distribute the remaining active power according to the active margin, so as to jointly complete the inertia frequency regulation;

[0182] Specifically, the reactive power allocation module is used to determine the autonomous voltage regulation support effect of the grid-type units according to the reactive margin of the grid-type units, and coordinate the grid-type units to distribute the remaining reactive power according to the reactive margin, and jointly implement the reactive target value.

[0183] In the embodiment of the present application, the acquisition and calculation module includes:

[0184] The data acquisition module is used to collect the frequency, voltage, active value, reactive value and system impedance of the high-voltage side of the grid connection point of the new energy station. The system impedance is the impedance of the internal step-up transformer and internal line of the new energy station, and the impedance of the line from the grid connection point of the station to the key nodes of the power grid;

[0185] The short-circuit ratio calculation module is used to calculate the short-circuit ratio of the new energy station based on the collected no-load operating voltage before the new energy is connected to the grid, the nominal voltage of the new energy grid connection point, the voltage change caused by the new energy grid connection, the reactive power change during the operation of the new energy, the grid connection voltage change during the operation of the new energy, and the impedance value between key nodes.

[0186] In an embodiment of the present application, the active power distribution module includes:

[0187] The first allocation module is used to calculate the primary frequency regulation active power target value of the new energy station when the frequency on the high-voltage side of the grid connection point of the new energy station exceeds the set frequency dead zone range, and to perform equal margin allocation among the units according to the active power margin and the primary frequency regulation active power target value of the new energy station;

[0188] The first calculation module is used to obtain the active power margin of each unit and compare the active power margin of the grid-type unit with the target value of the inertia frequency modulation active power of the station. When the frequency change rate of the high-voltage side of the grid connection point exceeds the preset frequency change rate dead zone range, the target value of the inertia frequency modulation active power of the station during the frequency disturbance is calculated according to the frequency change rate and active power value of the high-voltage side of the grid connection point;

[0189] The inertia frequency regulation action module is used for the grid-forming unit to autonomously perform inertia frequency regulation when the active power margin of the grid-forming unit meets the inertia frequency regulation requirements of the station;

[0190] The second allocation module is used to send the inertia frequency regulation action limit to the networking unit when the active power margin of the networking unit does not meet the inertia frequency regulation requirements of the station. The networking unit controls the active autonomous response amount not to exceed the frequency regulation action limit. At the same time, it coordinates the response of the grid-following unit to the inertia instruction, and distributes the remaining inertia frequency regulation active power target of the station with equal margin among the grid-following units.

[0191] In an embodiment of the present application, the reactive power distribution module includes:

[0192] The second calculation module is used to obtain the reactive margin of each unit and compare the reactive margin of the grid-type unit with the reactive power target value of the station voltage regulation. When the difference between the high-voltage side voltage of the grid-connected point and the preset voltage reference value exceeds the voltage dead zone range, the reactive power target value of the station voltage regulation when the system voltage is disturbed is calculated according to the short-circuit ratio of the new energy station, the high-voltage side voltage value of the grid-connected point, and the reactive value;

[0193] The voltage regulation action module is used for the grid-type unit to autonomously perform voltage regulation when the reactive power margin of the grid-type unit meets the voltage regulation requirements of the station;

[0194] The third allocation module is used to send the reactive power limit of voltage regulation action to the grid-building unit when the reactive power margin of the grid-building unit does not meet the voltage regulation requirement of the station. The grid-building unit controls the autonomous reactive power response amount not to exceed the reactive power limit of voltage regulation action, and coordinates the grid-following unit to respond to the reactive power instruction of voltage regulation, and distributes the remaining voltage regulation reactive power target of the station with equal margin among the grid-following units.

[0195] Embodiment 1 is a schematic scheme of an active support control method for a hybrid new energy station with a network. It should be noted that the technical solution of the system for active support control of a hybrid new energy station with a network belongs to the same concept as the technical solution of the active support control method for a hybrid new energy station with a network. For details not described in detail in the technical solution of the active support control system for a hybrid new energy station with a network in this embodiment, please refer to the description of the technical solution of the active support control method for a hybrid new energy station with a network.

[0196] It should be noted that if Figure 5 The figure shows the overall configuration principle diagram of the active support control system of the hybrid station with / building network, including the new energy station, active support controller, new energy power station main transformer, telecontrol and AGC / AVC main substation;

[0197] The active support controller obtains the status information of the new energy units of the new energy station, and updates and calculates the active and reactive support capabilities of each unit of the new energy station according to the status information of the new energy units;

[0198] The active support controller collects the no-load operating voltage before the new energy is connected to the grid, the nominal voltage of the new energy grid connection point, the voltage change caused by the new energy grid connection, the reactive power change during the operation of the new energy, the grid connection voltage change during the operation of the new energy, and the impedance value between key nodes to calculate the short-circuit ratio of the new energy station;

[0199] The active support controller obtains the voltage, frequency, and frequency change rate of the high-voltage side of the grid-connected point of the main transformer of the new energy power station, generates the reactive power demand of the grid-connected point according to the voltage of the high-voltage side of the grid-connected point, and generates the active power demand of the grid-connected point according to the frequency, frequency change rate, and active power of the high-voltage side of the grid-connected point;

[0200] The active support controller obtains the station active power set value and voltage reference value from the dispatching AGC / AVC master station through the telecontrol device, and realizes the coordination logic with the station AGC / AVC substation;

[0201] The active support controller switches the operating mode of the units with the following / structuring network switching function according to the short-circuit ratio calculated online, and coordinates the distribution among the following / structuring network units based on the active and reactive power margins of each unit and the required active and reactive power target values, so as to obtain the active and reactive power change command values ​​allocated to each unit in the new energy station, and transmit them to the converter or inverter of each unit respectively.

[0202] The above-mentioned unit modules may be embedded in or independent of a processor in a computer device in the form of hardware, or may be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to the above-mentioned modules.

[0203] This embodiment also provides a computing device, which includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless method can be implemented through WIFI, an operator network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for active support control of a hybrid new energy station with a network is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a button, trackball or touchpad set on the housing of the computer device, or an external keyboard, touchpad or mouse.

[0204] This embodiment also provides a storage medium on which a computer program is stored. When the program is executed by a processor, the method proposed in the above embodiment is implemented.

[0205] The storage medium proposed in this embodiment and the method proposed in the above embodiment belong to the same inventive concept. The technical details not fully described in this embodiment can be referred to the above embodiment, and this embodiment has the same beneficial effects as the above embodiment.

[0206] Through the above description of the implementation methods, the technicians in the relevant field can clearly understand that the present invention can be implemented by means of software and necessary general hardware, and of course can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ReadOnly, Memory, ROM), random access memory (RandomAccess Memory, RAM), flash memory (FLASH), hard disk or optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform the methods of various embodiments of the present invention.

[0207] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

[0208] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of complete hardware embodiments, complete software embodiments, or embodiments in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiments of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal scripting language JavaScript, etc.

[0209] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0210] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0211] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1The steps for the functions specified in one or more boxes.

[0212] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0213] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for active support control of a hybrid new energy station with a network, characterized in that: include: Collecting the operating status data of the high voltage side of the grid connection point of the new energy station, and calculating the short circuit ratio of the new energy station based on the operating status data; According to the short-circuit ratio of the new energy station, switching the operation mode of the unit with the grid-following / grid-building power generation mode; Obtain active power margin and reactive power margin of each unit based on the unit operation status; When the frequency of the high-voltage side of the grid connection point of the new energy station exceeds the set frequency dead zone range, the primary frequency regulation active power target value of the new energy station is calculated, and equal margin distribution is performed among the units according to the active power margin and the primary frequency regulation active power target value of the new energy station; The autonomous inertia support effect of the grid-forming units is determined according to the active power margin of the grid-forming units, and the grid-following units are coordinated to distribute the remaining active power according to the active power margin to jointly complete the inertia frequency regulation; The autonomous voltage regulation support effect of the grid-type units is judged according to the reactive margin of the grid-type units, and the grid-type units are coordinated to distribute the remaining reactive power according to the reactive margin, and the reactive target value is jointly implemented.

2. The active support control method for the hybrid new energy station with a network as claimed in claim 1 is characterized in that: According to the short-circuit ratio of the new energy station, the operation modes of the units that switch to the grid-following / grid-building generation modes include: Collect the frequency, voltage, active power value, reactive power value and system impedance of the high-voltage side of the grid connection point of the new energy station. The system impedance is the impedance of the internal step-up transformer and internal lines of the station, and the impedance of the lines from the grid connection point of the station to the key nodes of the power grid; The short-circuit ratio of the new energy station is calculated based on the collected no-load operating voltage before the new energy is connected to the grid, the nominal voltage of the new energy grid connection point, the voltage change caused by the new energy grid connection, the reactive power change during the operation of the new energy, the grid connection voltage change during the operation of the new energy, and the impedance value between the key nodes. The formula is expressed as follows: Among them, OSCR is the short-circuit ratio of the new energy station calculated online, U N is the rated system voltage at the grid connection point, It is the open circuit voltage of the grid connection point before the new energy is connected to the grid. is the voltage change caused by the connection of new energy to the grid, The voltage at the grid connection point of the new energy station; Comparing the short-circuit ratio of the new energy station with the critical short-circuit ratio of system stability; When the short-circuit ratio of the new energy station is less than the critical short-circuit ratio for stability of the system, the operating mode of the unit with the following / grid-building power generation mode will be switched to the grid-building mode; when the short-circuit ratio of the new energy station recovers to the stable operating short-circuit ratio, the operating mode of the unit with the following / grid-building power generation mode will be switched to the following mode.

3. The active support control method for the hybrid new energy station with a network as claimed in claim 2 is characterized in that: Obtaining the active margin of each unit includes: The upper regulation active margin of the wind turbine generator set is expressed as follows under the condition of unlimited power: The power limit regulation is expressed as: in, K is the effective capacity of wind turbines. s is the fan rotor kinetic energy utilization coefficient, E is the kinetic energy stored in the fan rotor, J is the fan rotational inertia, ω is the rotor speed, To adjust the effective capacity of wind turbines, The load reduction for wind turbines is is the output power of the wind turbine during maximum wind power tracking; The downward adjustment active power margin of the wind turbine is expressed as: in, To adjust the wind turbines to lower their functional capacity, The current active power of the fan, It is the minimum output power for stable operation of the fan; The active margin of the photovoltaic unit is 0 under unlimited power regulation and is expressed as: in, To adjust the functional capacity of photovoltaic units, The load reduction for photovoltaic units is is the output power of the photovoltaic unit during maximum light power tracking; The active power margin of the photovoltaic unit is expressed as: in, To adjust the photovoltaic unit to have functional capacity, The current active power of the PV inverter, It is the minimum output power for stable operation of the photovoltaic unit.

4. The active support control method for the hybrid new energy station with a network as claimed in claim 3 is characterized in that: Obtaining the reactive power margin of each unit includes: The reactive capacity range of the doubly-fed wind turbine generator system is expressed as: Among them, U S is the stator voltage, X S is the stator reactance, X m is the excitation impedance, I rmax is the maximum rotor current, P S is the stator active power, S C is the apparent power of the wind power converter, s is the slip rate, Q gmax is the maximum reactive power of the doubly-fed wind turbine, Q gmin is the minimum reactive capacity of the doubly-fed wind turbine generator set; The reactive capacity range of full-power wind turbines is expressed as: Among them, U g is the grid voltage, U c is the grid-side voltage of the grid-side converter, X is the grid-side voltage of the grid-side converter, P is the output active power of the wind power converter, Q Smax is the maximum powerless capacity of the full-power wind turbine, Q Smin It is the minimum dead capacity of full-power wind turbine; The reactive power range of a photovoltaic inverter is expressed as: Among them, U is the inverter output voltage, I is the inverter output current, P is the inverter active power, λ max Maximum power factor, λ min is the minimum power factor, Q pmax is the maximum powerless capacity of the photovoltaic inverter, Q pmin It is the minimum non-functional capacity of the photovoltaic inverter.

5. The active support control method for the hybrid new energy station with a network as claimed in claim 3 is characterized in that: The calculation of equal margin distribution among the units based on the active margin and the primary frequency regulation active power target value of the new energy station is: Where ΔP i is the primary frequency regulation active power instruction that the i-th unit needs to bear, ΔP t is the primary frequency modulation active power regulation at the current moment, P capi-inert is the remaining active power regulation capacity of the i-th unit after executing inertia frequency regulation, The remaining active power regulation capacity after inertia frequency regulation is performed for all grid-type units. It is the remaining active power regulation capability after executing inertia frequency regulation for all grid-following units.

6. The active support control method for the hybrid new energy station with a network as claimed in claim 5 is characterized in that: The jointly completing inertia frequency modulation includes: By obtaining the active power margin of each unit, the active power margin of the grid-connected unit and the active power target value of the station inertia frequency regulation are compared. When the frequency change rate on the high-voltage side of the grid-connected point exceeds the preset frequency change rate dead zone range, the station inertia frequency regulation active power target value during frequency disturbance is calculated based on the frequency change rate and active power value on the high-voltage side of the grid-connected point. When the active power margin of the grid-forming unit meets the inertia frequency regulation requirements of the station, the grid-forming unit autonomously performs inertia frequency regulation; When the active power margin of the grid-forming unit does not meet the inertia frequency regulation requirements of the station, the inertia frequency regulation action limit is sent to the grid-forming unit, and the grid-forming unit controls the active autonomous response amount not to exceed the frequency regulation action limit. At the same time, the grid-following units are coordinated to respond to the inertia instructions, and the remaining inertia frequency regulation active power target of the station is distributed equally among the grid-following units.

7. The active support control method for the hybrid new energy station with a network as claimed in claim 4 is characterized in that: The jointly executed reactive power target value includes: By obtaining the reactive margin of each unit, the reactive margin of the grid-type unit and the reactive power target value of the station voltage regulation are compared, wherein, when the difference between the high-voltage side voltage of the grid-connected point and the preset voltage reference value exceeds the voltage dead zone range, the reactive power target value of the station voltage regulation when the system voltage is disturbed is calculated according to the short-circuit ratio of the new energy station, the high-voltage side voltage value of the grid-connected point, and the reactive value; When the reactive power margin of the grid-forming unit meets the voltage regulation requirement of the station, the grid-forming unit autonomously performs voltage regulation; When the reactive power margin of the grid-forming unit does not meet the voltage regulation requirement of the station, the reactive power limit of the voltage regulation action is sent to the grid-forming unit, and the grid-forming unit controls the autonomous reactive response amount not to exceed the reactive power limit of the voltage regulation action. At the same time, the grid-following units are coordinated to respond to the reactive power instruction of the voltage regulation, and the remaining voltage regulation reactive power target of the station is distributed equally among the grid-following units.

8. A hybrid new energy station active support control system, characterized in that: include: A collection and calculation module, used to collect the operating status data of the high-voltage side of the grid connection point of the new energy station, and calculate the short-circuit ratio of the new energy station based on the operating status data; A grid-following switching module is used to switch the operation mode of the unit with grid-following / grid-following power generation mode according to the short-circuit ratio of the new energy station; Active / reactive margin acquisition module, used to obtain active margin and reactive margin of each unit based on the unit operation status; The active power distribution module is used to calculate the primary frequency regulation active power target value of the new energy station when the frequency of the high-voltage side of the grid connection point of the new energy station exceeds the set frequency dead zone range, and perform equal margin distribution among the units according to the active margin and the primary frequency regulation active power target value of the new energy station; judge the autonomous inertia support effect of the grid-forming unit according to the active margin of the grid-forming unit, and coordinate the grid-following unit to distribute the remaining active power according to the active margin, so as to jointly complete the inertia frequency regulation; The reactive power distribution module is used to determine the autonomous voltage regulation support effect of the grid-forming units according to the reactive margin of the grid-forming units, and coordinate the distribution of the remaining reactive power of the grid-forming units according to the reactive margin, and jointly implement the reactive target value.

9. An electronic device, comprising: Memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the active support control method for a hybrid new energy station with a follow-up network as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the steps of the active support control method for a hybrid new energy station with a network structure as described in any one of claims 1 to 7.

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