Inertia support control method and system based on flywheel array frequency response characteristics

Abstract

The invention discloses a flywheel array frequency response characteristic-based inertia support control method and system. The method comprises the following steps of: acquiring a real-time frequency signal and real-time system power of a flywheel energy storage system grid-connected point; determining a real-time frequency deviation value generated by source load fluctuation according to the real-time frequency signal and a rated value; if the real-time frequency deviation value exceeds the power grid dead zone constraint, the flywheel energy storage system calculates the frequency fluctuation change rate of a grid-connected point where the flywheel energy storage system is located according to the real-time frequency signal; calculating a virtual inertia time constant according to the frequency fluctuation change rate; according to the virtual inertia time constant and the real-time frequency signal, calculating the power demand of the flywheel energy storage system participating in inertia support; and based on the power demand of the wheel energy storage system participating in inertia support, flywheel array frequency response characteristics are aggregated, and the action for controlling the flywheel array is determined. And the technical effect of maximally utilizing and flexibly adjusting resources to improve the inertia supporting capability of the power grid is achieved.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology and power system auxiliary services, and in particular to an inertial support control method and system based on the frequency response characteristics of a flywheel array. Background Art

[0002] The high proportion of renewable energy generation has posed a challenge to the stability of the grid frequency. First, the volatility, intermittency and anti-regulation of renewable energy generation affect the balance of power consumption and power generation in the grid, thereby affecting the stability of the grid frequency. On the other hand, the high penetration of renewable energy reduces the inherent inertia of the grid, making the frequency regulation of the system more difficult. Therefore, new regulation methods are urgently needed to support the frequency stability of the grid and promote the realization of the dual carbon goals.

[0003] In recent years, the demonstration and application of flywheel energy storage has been gradually promoted at home and abroad. Flywheel energy storage technology has advantages in inertia support and primary frequency regulation due to its fast response and high power density. Under the time scale of electromechanical transients, the inertia process of the power grid significantly affects the dynamic frequency characteristics of the traditional power system after disturbance. Existing research on virtual inertia support and control methods of flywheel energy storage systems is relatively rare. Summary of the invention

[0004] In view of the above technical problems, the present invention provides an inertial support control method and system based on the frequency response characteristics of a flywheel array, the method comprising:

[0005] Obtain the real-time frequency signal and real-time system power of the flywheel energy storage system grid connection point;

[0006] According to the real-time frequency signal and the rated value, a real-time frequency deviation value generated by source-load fluctuation is determined; if the real-time frequency deviation value exceeds the grid dead zone constraint, the flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal;

[0007] Calculating a virtual inertia time constant according to the frequency fluctuation change rate;

[0008] Calculating the power demand of the flywheel energy storage system participating in inertia support according to the virtual inertia time constant and the real-time frequency signal;

[0009] Based on the power demand of the wheel energy storage system participating in inertia support, the frequency response characteristics of the flywheel array are aggregated to determine the action of controlling the flywheel array.

[0010] Further, determining a real-time frequency deviation value caused by source load fluctuation according to the real-time frequency signal and the rated value includes:

[0011] The real-time frequency signal f iSubtract the rated value to determine the real-time frequency deviation Δf caused by source load fluctuation i , the specific formula is:

[0012] Δf i =f e -f i

[0013] Where Δf i Indicates the frequency deviation caused by load fluctuation; f i represents the real-time frequency value collected at the bus where the flywheel energy storage system is located, f e Indicates the rated frequency.

[0014] Furthermore, the flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal. The specific formula is:

[0015]

[0016] Among them, λ i represents the frequency change rate at the grid connection point of the flywheel energy storage system; t represents the time window corresponding to the frequency change rate.

[0017] Furthermore, according to the frequency fluctuation change rate, the virtual inertia time constant is calculated, and the specific formula is:

[0018]

[0019] Among them, H F represents the virtual inertia time constant of the flywheel energy storage system; P e Indicates the rated power of the flywheel energy storage system; Indicates that at t a The power of the flywheel grid connection point when the frequency exceeds the FM control dead zone; Indicates that at t a The frequency of the flywheel grid connection point when the frequency crosses the FM control dead zone.

[0020] Furthermore, the power demand of the flywheel energy storage system participating in inertia support is calculated according to the virtual inertia time constant and the real-time frequency signal. The specific formula is:

[0021]

[0022] Among them, ΔP i It represents the inertia power demand supported by the flywheel energy storage system at the grid connection point at all times.

[0023] Furthermore, based on the power demand of the wheel energy storage system participating in the inertia support, the frequency response characteristics of the flywheel array are aggregated to determine the action of controlling the flywheel array, including:

[0024] Considering the power constraints of each array in the flywheel energy storage system, the frequency response characteristics of the array are aggregated and the action depth of each flywheel array participating in the inertia support is determined according to the following formula:

[0025]

[0026] Among them, P F.n.i represents the power output value of the nth array of the flywheel energy storage system at time i; ΔP F.n.i represents the output value of the standby power of the nth array of the flywheel energy storage system at time i; P F.n.max represents the maximum output power of the nth array of the flywheel energy storage system; P F.n.comma.i It represents the inertia support power output command value of the nth array of the flywheel energy storage system at time i.

[0027] The present invention also provides an inertial support control system based on the frequency response characteristics of a flywheel array, comprising:

[0028] A signal and power acquisition module is used to obtain the real-time frequency signal and real-time system power of the flywheel energy storage system grid connection point;

[0029] A frequency fluctuation change rate calculation module is used to determine the real-time frequency deviation value caused by source-load fluctuation according to the real-time frequency signal and the rated value; if the real-time frequency deviation value exceeds the grid dead zone constraint, the flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal;

[0030] A time constant calculation module, used for calculating a virtual inertia time constant according to the frequency fluctuation change rate;

[0031] A power demand calculation module, used to calculate the power demand of the flywheel energy storage system participating in inertia support according to the virtual inertia time constant and the real-time frequency signal;

[0032] The flywheel array action control module is used to aggregate the frequency response characteristics of the flywheel array based on the power demand of the wheel energy storage system participating in the inertia support, and determine the action of controlling the flywheel array.

[0033] Furthermore, the frequency fluctuation change rate calculation module includes:

[0034] The frequency deviation value calculation submodule is used to convert the real-time frequency signal f i Subtract the rated value to determine the real-time frequency deviation Δf caused by source load fluctuation i , the specific formula is:

[0035] Δf i =f e-f i

[0036] Where Δf i Indicates the frequency deviation caused by load fluctuation; f i represents the real-time frequency value collected at the bus where the flywheel energy storage system is located, f e Indicates the rated frequency.

[0037] Furthermore, the frequency fluctuation change rate calculation module includes:

[0038] The frequency fluctuation change rate calculation submodule has the following calculation formula:

[0039]

[0040] Among them, λ i represents the frequency change rate at the grid connection point of the flywheel energy storage system; t represents the time window corresponding to the frequency change rate.

[0041] Furthermore, the flywheel array motion control module includes:

[0042] The action depth determination submodule is used to consider the power constraints of each array in the flywheel energy storage system, apply the frequency response characteristics of the array to aggregate, and determine the action depth of each flywheel array participating in the inertia support according to the following formula:

[0043]

[0044] Among them, P F.n.i represents the power output value of the nth array of the flywheel energy storage system at time i; ΔP F.n.i represents the output value of the standby power of the nth array of the flywheel energy storage system at time i; P F.n.max represents the maximum output power of the nth array of the flywheel energy storage system; P F.n.comma.i It represents the inertia support power output command value of the nth array of the flywheel energy storage system at time i.

[0045] The present invention provides an inertia support control method and system based on the frequency response characteristics of a flywheel array, which determines the power demand of the flywheel energy storage system for inertia support, combines the power constraints of the flywheel energy storage array, and uses the frequency response characteristics of the array to aggregate and adjust the actual action depth of the flywheel array. The present invention solves the control problem in the prior art that the flywheel energy storage output cannot be optimized and adjusted based on the frequency response characteristics of the flywheel array to support the inertia application, and achieves the technical effect of maximizing the use of flexible adjustment resources to enhance the inertia support capacity of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1It is a flow chart of an inertial support control method based on the frequency response characteristics of a flywheel array provided by an embodiment of the present invention;

[0047] Figure 2 It is a block diagram of primary frequency modulation control of flywheel energy storage based on variable droop coefficient involved in an embodiment of the present invention;

[0048] Figure 3 is a schematic diagram of the SOC region of the flywheel energy storage array involved in the embodiment of the present invention;

[0049] Figure 4 It is a structural schematic diagram of an inertial support control system based on the frequency response characteristics of a flywheel array provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0050] Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention, so the present invention is not limited to the specific implementation disclosed below.

[0051] Example 1

[0052] The embodiment of the present invention provides an inertia support control method based on the frequency response characteristics of a flywheel array, and the process is as follows: Figure 1 As shown, in order to solve the control problem in the prior art that the flywheel energy storage output cannot be adjusted according to the flywheel array frequency response characteristics to support inertia application, the method includes the following steps:

[0053] Step S101, obtaining the real-time frequency signal and real-time system power of the flywheel energy storage system grid connection point.

[0054] Step S102, determining a real-time frequency deviation value caused by source-load fluctuations according to the real-time frequency signal and the rated value; if the real-time frequency deviation value exceeds the grid dead zone constraint, the flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal.

[0055] After determining that the grid frequency deviates from the rated value, the frequency is collected by the frequency collection device at the grid connection point where the flywheel energy storage system is located, and the real-time frequency signal f i Subtract the rated value to determine the real-time frequency deviation Δf caused by source load fluctuation i , the specific formula is:

[0056] Δf i =f e -f i

[0057] Where Δf iIndicates the frequency deviation caused by load fluctuation; f i represents the real-time frequency value collected at the bus where the flywheel energy storage system is located, f e Indicates the rated frequency.

[0058] After receiving the step signal of system startup, the frequency change rate at the grid connection point is calculated according to the frequency fluctuation magnitude of the grid connection point where the flywheel energy storage system is located. The specific formula is:

[0059]

[0060] Among them, λ i represents the frequency change rate at the grid connection point of the flywheel energy storage system; t represents the time window corresponding to the frequency change rate (t = 1s, or 2s, or t a ,or...).

[0061] Step S103, calculating a virtual inertia time constant according to the frequency fluctuation change rate.

[0062] After receiving the system frequency change rate information, the virtual inertia time constant of the flywheel energy storage system is calculated by the following formula:

[0063]

[0064] Among them, H F represents the virtual inertia time constant of the flywheel energy storage system; P e Indicates the rated power of the flywheel energy storage system; Indicates that at t a The power of the flywheel grid connection point when the frequency exceeds the FM control dead zone; Indicates that at t a The frequency of the flywheel grid connection point when the frequency crosses the FM control dead zone.

[0065] Step S104: Calculate the power demand of the flywheel energy storage system participating in inertia support according to the virtual inertia time constant and the real-time frequency signal.

[0066] After receiving the virtual inertia time constant, the power demand of the flywheel energy storage system participating in inertia support is calculated by the following formula:

[0067]

[0068] Among them, ΔP i It represents the inertia power demand supported by the flywheel energy storage system at the grid connection point at all times.

[0069] Step S105: Based on the power demand of the wheel energy storage system participating in the inertia support, the frequency response characteristics of the flywheel array are aggregated to determine the action of controlling the flywheel array.

[0070] Considering the power constraints of each array in the flywheel energy storage system, the frequency response characteristics of the array are aggregated and the action depth of each flywheel array participating in the inertia support is determined according to the following formula:

[0071]

[0072] Among them, P F.n.i represents the power output value of the nth array of the flywheel energy storage system at time i; ΔP F.n.i represents the output value of the standby power of the nth array of the flywheel energy storage system at time i; P F.n.max represents the maximum output power of the nth array of the flywheel energy storage system; P F.n.comma.i It represents the inertia support power output command value of the nth array of the flywheel energy storage system at time i.

[0073] Example 2

[0074] like Figure 2 The flywheel energy storage primary frequency modulation control block diagram based on variable droop coefficient is shown in the figure, and the specific steps of controlling the inertia support command are as follows:

[0075] Step 1, the frequency fluctuation judgment module collects the frequency signal sent by the frequency acquisition device at the grid-connected bus where the flywheel energy storage system is located, subtracts the signal from the rated value (50HZ in my country), calculates the real-time frequency deviation value caused by source-load fluctuation, and determines whether to start the frequency change rate calculation module in combination with the grid dead zone constraint. If yes, proceed to step (2), otherwise loop (1);

[0076] Step 2, the frequency change rate calculation module calculates the frequency change rate of the flywheel energy storage system grid connection point according to the frequency deviation value described in step 1 as an input signal;

[0077] Step 3, a virtual inertia time constant calculation module calculates a virtual inertia time constant of the flywheel energy storage system according to the frequency change rate value in step 2 as an input signal;

[0078] Step 4: The inertia support feedback adjustment module calculates the power demand of the flywheel energy storage system participating in the inertia support according to the virtual inertia time constant described in step (3), combines the power constraint of the flywheel array, and aggregates the frequency response characteristics of the array to calculate the action depth of the flywheel array participating in the inertia support.

[0079] Among them, in step (1), the frequency fluctuation judgment module collects the real-time frequency signal f fed back by the frequency sensing logic control loop at the bus where the flywheel energy storage system is connected to the grid i After that, the real-time frequency value f iSubtract the actual frequency from the rated frequency by 50 Hz to get the deviation Δf between the actual frequency and the rated frequency. i , that is, Δf i =f i -50, and based on Δf i Make judgment and assign value: When -0.033HZ≤Δf i ≤0.033HZ, the frequency change rate calculation module is not started, and step (1) is repeated; if 0.033HZ<Δf i <0.2HZ or -0.2HZ<Δf i <-0.033HZ, the frequency change rate calculation module is started and the real-time frequency f i , and the real-time flywheel energy storage system power P collected by the grid-connected power measurement device i Send to the frequency change rate calculation module.

[0080] In step (2), the frequency change rate calculation module is started and receives the real-time frequency signal f i , calculate the frequency fluctuation rate λ of the grid connection point where the flywheel energy storage system is located i ,Right now

[0081] (t=1s, or 2s, or t a , or ...), and f i , P i , i The parameter information is sent to the virtual inertia time constant calculation module.

[0082] In step (3), the virtual inertia time constant calculation module is started and receives the frequency change rate signal λ i , calculate the virtual inertia time constant H F ,Right now (t a indicates the moment when the frequency crosses the FM control dead zone), and f i , P i , H F Transmitted to the inertia support feedback adjustment module.

[0083] In step (4), the inertia support feedback adjustment module is started and receives the inertia time constant H F , Real-time frequency of the grid connection point f i , real-time output power P of flywheel energy storage system i , real-time acquisition of the SOC state of the flywheel array, the real-time output power P of the flywheel array F.n.i , calculate the power demand ΔP of the flywheel energy storage system participating in inertia support i ,Right now Further calculate the reserve power output value ΔP of the flywheel array F.n.i , that is, ΔP F.n.i =P F.n.max -P F.n.i .

[0084] Wherein, in step (4), the SOC of the flywheel energy storage system refers to the state of charge of each flywheel array rotor, and the state of charge value SOC i Different, divided into five areas, such as Figure 3 As shown, including:

[0085] Zone I is the upper restricted zone: SOC i >SOC max ;

[0086] Zone II is the downward tracking zone: 50% SOC e ≤SOC i ≤SOC max ;

[0087] Zone III is the regression zone: SOC i ≈50% SOC e ;

[0088] Zone IV is the upward tracking zone: SOC max ≤SOC i ≤50% SOC e ;

[0089] Zone V is the lower restricted zone: SOC i <SOC min ;

[0090] Among them, SOC min The minimum SOC value for efficient operation of the flywheel rotor. max The maximum SOC value for efficient operation of the flywheel rotor, SOC e is the rated charge state of the flywheel rotor.

[0091] In step (4), the inertia support feedback adjustment module controls the flywheel array based on the inertia power demand, and the control of power optimization distribution of each array includes the following steps:

[0092] If SOC min ≤SOC i ≤SOC max , and Flywheel energy storage system array n The size of the power released or absorbed to the grid connection point;

[0093] If SOC min ≤SOC i≤SOC max , and as well as Flywheel energy storage system array n with P F.n.comma.i =ΔP F.n.i The size of the power released or absorbed to the grid connection point;

[0094] If SOC min ≤SOC i ≤SOC max , and as well as Flywheel energy storage system array n The size of the power released or absorbed to the grid connection point;

[0095] If SOC min ≤SOC i ≤SOC max , and Flywheel energy storage system array n with P F.n.comma.i =ΔP F.n.i The size of the power released or absorbed to the grid connection point;

[0096] If SOC min ≤SOC i ≤SOC max ,and Flywheel energy storage system array n with P F.n.comma.i =ΔP F.n.i The size of the power released or absorbed to the grid connection point;

[0097] If ΔP i =0, SOC i >50%SOC e , the flywheel energy storage array n is P F.n.comma.i =1%P e.n (P e.n The power of the flywheel energy storage array is the rated power of the flywheel energy storage array) and the power is released to the bus feeder to make the SOC of the flywheel array n return to 50% SOC e Charge state, prepare for the next inertia support service;

[0098] If ΔP i =0, SOC i <50%SOC e , the energy storage system is based on P F.n.comma.i =1%P e.n (P e.n The power of the flywheel energy storage array is the rated power of the flywheel energy storage array) to absorb power from the bus feeder, so that the SOC of the flywheel array n returns to 50% SOC eCharge state, prepare for the next inertia support service;

[0099] SOC i <SOC min , then the flywheel energy storage array does not act;

[0100] SOC i >SOC max , the flywheel energy storage array does not operate.

[0101] In step (4), the inertia support feedback adjustment module controls the flywheel array based on the inertia power demand, and the control command for optimizing the power distribution of each array includes:

[0102] If SOC min ≤SOC i ≤SOC max , -0.2HZ<Δf i <-0.033HZ, and When , the output of the flywheel energy storage system array n is P F.n.comma.i The charge and discharge status flag(i) = 1;

[0103] If SOC min ≤SOC i ≤SOC max , -0.2HZ<Δf i <-0.033HZ,

[0104] and When , the output of the flywheel energy storage system array n is P F.n.comma.i =ΔP F.n.i , P F.n.comma.i The charge and discharge status flag(i) = 1;

[0105] If SOC min ≤SOC i ≤SOC max , -0.2HZ<Δf i <-0.033HZ,

[0106] and When , the output of the flywheel energy storage system array n is P F.n.comma.i The charge and discharge status flag(i) = 1;

[0107] If SOC min ≤SOC i ≤SOC max, -0.2HZ<Δf i <-0.033HZ, and When , the output of the flywheel energy storage system array n is P F.n.comma.i =ΔP F.n.i , P F.n.comma.i The charge and discharge status flag(i) = 1;

[0108] If SOC min ≤SOC i ≤SOC max , -0.2HZ<Δf i <-0.033HZ, and When , the output of the flywheel energy storage system array n is P F.n.comma.i =ΔP F.n.i , P F.n.comma.i The charge and discharge status flag(i) = 1;

[0109] If SOC min ≤SOC i ≤SOC max , 0.033HZ<Δf i <0.2HZ, and When , the output of the flywheel energy storage system array n is P F.n.comma.i The charge and discharge status flag(i) = -1;

[0110] If SOC min ≤SOC i ≤SOC max , 0.033HZ<Δf i <0.2HZ,

[0111] and When , the output of the flywheel energy storage system array n is P F.n.comma.i =-ΔP F.n.i , P F.n.comma.i The charge and discharge status flag(i) = -1;

[0112] If SOC min ≤SOC i ≤SOC max , 0.033HZ<Δf i <0.2HZ,

[0113] and When , the output of the flywheel energy storage system array n is P F.n.comma.iThe charge and discharge status flag(i) = -1;

[0114] If SOC min ≤SOC i ≤SOC max , 0.033HZ<Δf i <0.2HZ, and When , the output of the flywheel energy storage system array n is P F.n.comma.i =-ΔP F.n.i , P F.n.comma.i The charge and discharge status flag(i) = -1;

[0115] If SOC min ≤SOC i ≤SOC max , 0.033HZ<Δf i <0.2HZ, and When , the output of the flywheel energy storage system array n is P F.n.comma.i =-ΔP F.n.i , P F.n.comma.i The charge and discharge status flag(i) = -1;

[0116] If ΔP i =0, SOC i >50%SOC e , then the output of the flywheel energy storage system array n is P F.n.comma.i =1%P e.n , P F.n.comma.i The charge and discharge status flag(i) = 1;

[0117] If ΔP i =0, SOC i <50%SOC e , then the output of the flywheel energy storage system array n is P F.n.comma.i =-1%P e.n , P F.n.comma.i The charging and discharging status flag(i) = -1.

[0118] Among them, according to P F.n.comma.i The positive and negative signs of the flywheel energy storage array n determine the charge and discharge state, P F.n.comma.i <0, flag(i)=-1 indicates that the energy storage system is charging; P F.n.comma.i >0, flag(i)=1 indicates that the energy storage system is discharging, and the power value |P F.n.comma.i | and the charge and discharge status flag(i) of the flywheel energy storage array n are sent to the inertia support feedback adjustment module, and the inertia support feedback adjustment module controls the charge and discharge support inertia adjustment demand of the flywheel energy storage array n.

[0119] Example 3

[0120] Based on the same inventive concept, the present invention also provides an inertial support control system 400 based on the frequency response characteristics of the flywheel array, such as Figure 4 As shown, including:

[0121] The signal and power acquisition module 410 is used to obtain the real-time frequency signal and real-time system power of the flywheel energy storage system grid connection point;

[0122] The frequency fluctuation change rate calculation module 420 is used to determine the real-time frequency deviation value caused by the source-load fluctuation according to the real-time frequency signal and the rated value; if the real-time frequency deviation value exceeds the grid dead zone constraint, the flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal;

[0123] A time constant calculation module 430, used to calculate a virtual inertia time constant according to the frequency fluctuation change rate;

[0124] A power demand calculation module 440, used to calculate the power demand of the flywheel energy storage system participating in inertia support according to the virtual inertia time constant and the real-time frequency signal;

[0125] The flywheel array action control module 450 is used to aggregate the frequency response characteristics of the flywheel array based on the power demand of the wheel energy storage system participating in the inertia support, and determine the action of controlling the flywheel array.

[0126] Furthermore, the frequency fluctuation change rate calculation module includes:

[0127] The frequency deviation value calculation submodule is used to convert the real-time frequency signal f i Subtract the rated value to determine the real-time frequency deviation Δf caused by source load fluctuation i , the specific formula is:

[0128] Δf i =f e -f i

[0129] Where Δf i Indicates the frequency deviation caused by load fluctuation; f i represents the real-time frequency value collected at the bus where the flywheel energy storage system is located, f e Indicates the rated frequency.

[0130] Furthermore, the frequency fluctuation change rate calculation module includes:

[0131] The frequency fluctuation change rate calculation submodule has the following calculation formula:

[0132]

[0133] Among them, λ i represents the frequency change rate at the grid connection point of the flywheel energy storage system; t represents the time window corresponding to the frequency change rate.

[0134] Furthermore, the flywheel array motion control module includes:

[0135] The action depth determination submodule is used to consider the power constraints of each array in the flywheel energy storage system, apply the frequency response characteristics of the array to aggregate, and determine the action depth of each flywheel array participating in the inertia support according to the following formula:

[0136]

[0137] Among them, P F.n.i represents the power output value of the nth array of the flywheel energy storage system at time i; ΔP F.n.i represents the output value of the standby power of the nth array of the flywheel energy storage system at time i; P F.n.max represents the maximum output power of the nth array of the flywheel energy storage system; P F.n.comma.i It represents the inertia support power output command value of the nth array of the flywheel energy storage system at time i.

[0138] The present invention provides an inertia support control method and system based on the frequency response characteristics of a flywheel array, which determines the power demand of the flywheel energy storage system for inertia support, combines the power constraints of the flywheel energy storage array, and uses the frequency response characteristics of the array to aggregate and adjust the actual action depth of the flywheel array. The present invention solves the control problem in the prior art that the flywheel energy storage output cannot be optimized and adjusted based on the frequency response characteristics of the flywheel array to support the inertia application, and achieves the technical effect of maximizing the use of flexible adjustment resources to enhance the inertia support capacity of the power grid.

[0139] Those skilled in the art will appreciate that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present invention may take 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.) containing computer-usable program code.

[0140] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks 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 produce 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.

[0141] 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 including 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.

[0142] 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 1 The steps for the functions specified in one or more boxes.

[0143] Finally, 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 above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents, and any modifications or equivalents that do not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

Claims

1. An inertial support control method based on the frequency response characteristics of a flywheel array, characterized in that: include: Obtain the real-time frequency signal and real-time system power of the flywheel energy storage system grid connection point; According to the real-time frequency signal and the rated value, a real-time frequency deviation value generated by source-load fluctuation is determined; if the real-time frequency deviation value exceeds the grid dead zone constraint, the flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal; Calculating a virtual inertia time constant according to the frequency fluctuation change rate; Calculating the power demand of the flywheel energy storage system participating in inertia support according to the virtual inertia time constant and the real-time frequency signal; Based on the power demand of the wheel energy storage system participating in inertia support, the frequency response characteristics of the flywheel array are aggregated to determine the action of controlling the flywheel array.

2. The method according to claim 1, characterized in that Determining a real-time frequency deviation value caused by source-load fluctuation according to the real-time frequency signal and the rated value includes: The real-time frequency signal f i Subtract the rated value to determine the real-time frequency deviation Δf caused by source load fluctuation i , the specific formula is: Δf i =f e -f i Where Δf i Indicates the frequency deviation caused by load fluctuation; f i represents the real-time frequency value collected at the bus where the flywheel energy storage system is located, f e Indicates the rated frequency.

3. The method according to claim 1, characterized in that The flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal. The specific formula is: Among them, λ i It represents the frequency change rate at the grid connection point of the flywheel energy storage system; t represents the time window corresponding to the frequency change rate.

4. The method according to claim 1, characterized in that: According to the frequency fluctuation change rate, the virtual inertia time constant is calculated, and the specific formula is: Among them, H F represents the virtual inertia time constant of the flywheel energy storage system; P e Indicates the rated power of the flywheel energy storage system; Indicates that at t a The power of the flywheel grid connection point when the frequency exceeds the FM control dead zone; Indicates that at t a The frequency of the flywheel grid connection point when the frequency crosses the FM control dead zone.

5. The method according to claim 1, characterized in that According to the virtual inertia time constant and the real-time frequency signal, the power demand of the flywheel energy storage system participating in the inertia support is calculated. The specific formula is: Among them, ΔP i It represents the inertia power demand supported by the flywheel energy storage system at the grid connection point at all times.

6. The method according to claim 1, characterized in that Based on the power demand of the wheel energy storage system participating in the inertia support, the frequency response characteristics of the flywheel array are aggregated to determine the action of controlling the flywheel array, including: Considering the power constraints of each array in the flywheel energy storage system, the frequency response characteristics of the array are aggregated and the action depth of each flywheel array participating in the inertia support is determined according to the following formula: Among them, P F.n.i represents the power output value of the nth array of the flywheel energy storage system at time i; ΔP F.n.i represents the output value of the standby power of the nth array of the flywheel energy storage system at time i; P F.n.max represents the maximum output power of the nth array of the flywheel energy storage system; P F.n.comma.i It represents the inertia support power output command value of the nth array of the flywheel energy storage system at time i.

7. An inertial support control system based on the frequency response characteristics of a flywheel array, characterized in that: include: A signal and power acquisition module is used to obtain the real-time frequency signal and real-time system power of the flywheel energy storage system grid connection point; A frequency fluctuation change rate calculation module is used to determine the real-time frequency deviation value caused by source-load fluctuation according to the real-time frequency signal and the rated value; if the real-time frequency deviation value exceeds the grid dead zone constraint, the flywheel energy storage system calculates the frequency fluctuation change rate of the grid connection point where the flywheel energy storage system is located according to the real-time frequency signal; A time constant calculation module, used for calculating a virtual inertia time constant according to the frequency fluctuation change rate; A power demand calculation module, used to calculate the power demand of the flywheel energy storage system participating in inertia support according to the virtual inertia time constant and the real-time frequency signal; The flywheel array action control module is used to aggregate the frequency response characteristics of the flywheel array based on the power demand of the wheel energy storage system participating in the inertia support, and determine the action of controlling the flywheel array.

8. The system according to claim 7, characterized in that Frequency fluctuation change rate calculation module, including: The frequency deviation value calculation submodule is used to convert the real-time frequency signal f i Subtract the rated value to determine the real-time frequency deviation Δf caused by source load fluctuation i , the specific formula is: Δf i =f e -f i Where Δf i Indicates the frequency deviation caused by load fluctuation; f i represents the real-time frequency value collected at the bus where the flywheel energy storage system is located, f e Indicates the rated frequency.

9. The system according to claim 7, characterized in that Frequency fluctuation change rate calculation module, including: The frequency fluctuation change rate calculation submodule has the following calculation formula: Among them, λ i It represents the frequency change rate at the grid connection point of the flywheel energy storage system; t represents the time window corresponding to the frequency change rate.

10. The system according to claim 7, characterized in that Flywheel array motion control module, including: The action depth determination submodule is used to consider the power constraints of each array in the flywheel energy storage system, apply the frequency response characteristics of the array to aggregate, and determine the action depth of each flywheel array participating in the inertia support according to the following formula: Among them, P F.n.i represents the power output value of the nth array of the flywheel energy storage system at time i; ΔP F.n.i represents the output value of the standby power of the nth array of the flywheel energy storage system at time i; P F.n.max represents the maximum output power of the nth array of the flywheel energy storage system; P F.n.comma.i It represents the inertia support power output command value of the nth array of the flywheel energy storage system at time i.

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