A method and system for damping power system active power control of disturbances

Abstract

The application relates to a power system active power control method and system for weakening disturbance, comprising the following steps: determining feedforward power of a power system according to frequency modulation power withdrawn by a demand side in the power system; and adjusting active power of the power system according to the feedforward power of the power system. The technical scheme provided by the application can mobilize power generation side resources in advance through a feedforward control method when dynamic demand response resources are withdrawn, provide active power compensation for the power system, reduce power system disturbance caused when the dynamic demand response resources are withdrawn, and improve the steady-state performance of the power system.

Description

Technical Field

[0001] The present invention relates to the technical field of power system automation, and in particular to a power system active power control method and system for weakening disturbances. Background Art

[0002] In traditional power system frequency control, primary frequency regulation and secondary frequency regulation are two very important frequency regulation methods.

[0003] With the improvement of demand-side management and the increase of demand-side resource controllability, dynamic demand response participates in the frequency control of the power system, which can contribute to reducing the maximum frequency deviation of the system under conditions such as large power shortage and improving system stability. The typical dynamic demand response participates in the power system frequency control block diagram, such as Figure 1 However, this inevitably leads to some problems. For example, when dynamic demand response resources are withdrawn, it will cause disturbances to the power system and aggravate the active power imbalance of the system.

[0004] Currently, there is no technology that can utilize dynamic demand response resources to improve system stability while also mitigating disturbances caused by resource withdrawal. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the purpose of the present invention is to propose an active power control method for an electric power system for weakening the power system disturbance caused by the withdrawal of dynamic demand response resources. When the dynamic demand response resources are withdrawn, the method mobilizes the power generation side resources in advance through a feedforward control method to provide active power compensation for the power system, reduce the power system disturbance caused by the withdrawal of dynamic demand response resources, and improve the steady-state performance of the power system.

[0006] The purpose of the present invention is achieved by adopting the following technical solutions:

[0007] The present invention provides a method for controlling active power of an electric power system for weakening disturbances, wherein the method comprises:

[0008] Determine the feedforward power of the power system based on the frequency regulation power withdrawn from the demand side of the power system;

[0009] The active power of the power system is adjusted according to the feedforward power of the power system.

[0010] Preferably, determining the feedforward power of the power system according to the frequency regulation power withdrawn from the demand side of the power system includes:

[0011] Calculate the frequency regulation power withdrawn from the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn from the demand side of the power system at the time t+Δt;

[0012] Determine whether the difference between the frequency regulation power withdrawn on the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt is 0. If so, end the operation; if not, calculate the feedforward power of the power system at the current time t based on the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt;

[0013] Where Δt is the response time difference between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system.

[0014] Furthermore, the calculation of the frequency regulation power withdrawn by the demand side in the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side in the power system at the time t+Δt includes:

[0015] The frequency regulation power P withdrawn by the demand side in the power system at the current time t is determined as follows: DDRL,t :

[0016]

[0017] Where, P DDRM The demand-side frequency regulation power before the dynamic demand response resource of the power system is withdrawn; f t is the frequency of the power system at the current moment t;

[0018] The frequency regulation power P expected to be withdrawn on the demand side of the power system at time t+Δt is determined by the following formula: DDRL,t+Δt :

[0019]

[0020] Where, f t+Δt is the frequency of the power system at time t+Δt;

[0021] The frequency f of the power system at time t+Δt is determined as follows: t+Δt :

[0022] f t+Δt =f t +Δt(f t '+αP DDR )

[0023] Where, f t ' is the derivative of the frequency of the power system at the current time t; α is the frequency coefficient of the power system; P DDR is the demand-side frequency regulation power of the power system at the current moment t.

[0024] The demand-side frequency regulation power P of the power system at the current moment t is determined as follows: DDR :

[0025] P DDR (t) = P DDRM-P DDRL,t

[0026] Where, P DDRM It is the demand-side frequency regulation power before the dynamic demand response resources of the power system are withdrawn.

[0027] Furthermore, the calculation of the feedforward power of the power system at the current time t according to the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt includes:

[0028] The feedforward power P of the power system at the current time t is determined as follows: FF (t):

[0029]

[0030] Where K f is the static amplification factor in the demand side transfer function; K0 is the static amplification factor in the power generation side transfer function; P DDRL,t+Δt is the frequency regulation power expected to be withdrawn on the demand side of the power system at time t+Δt.

[0031] Furthermore, the response time difference Δt between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system is determined as follows:

[0032] Δt=4.75T t -4T d

[0033] Where, T t is the time constant of the turbine; T d is the response time constant on the demand side.

[0034] Preferably, regulating the active power of the power system according to the feedforward power of the power system includes:

[0035] Determine the active power P of the power system at the current time t by the following formula: t :

[0036] P t =[ΔP S (t)-ΔP P (t)+P FF (t)]·H1(s)+P DDR (t)·H2(s)-ΔP L

[0037] Where ΔP S (t) is the secondary frequency regulation power on the power generation side of the power system at the current time t; ΔP P (t) is the primary frequency regulation power of the power generation side of the power system at the current time t; P FF(t) is the feedforward power of the power system at the current moment t; H1(s) is the transfer function of the power system generation side; P DDR (t) is the demand-side frequency regulation power of the power system at the current time t; H2(s) is the demand-side transfer function of the power system; ΔP L is the self-disturbance power of the power system;

[0038] The power system generation side transfer function H1(s) is determined as follows:

[0039]

[0040] Where s is the Laplace operator; K0 is the static amplification factor in the transfer function on the power generation side; T g is the time constant of the speed regulator; T t is the time constant of the turbine;

[0041] The power system demand side transfer function H2(s) is determined as follows:

[0042]

[0043] Where K f is the static amplification coefficient in the demand side transfer function; T d is the response time constant on the demand side.

[0044] The present invention provides an electric power system active power control system for weakening disturbances, wherein the improvement is that the system comprises:

[0045] A determination module, configured to determine the feedforward power of the power system according to the frequency regulation power withdrawn from the demand side of the power system;

[0046] The regulating module is used to regulate the active power of the power system according to the feedforward power of the power system.

[0047] Preferably, the determining module includes:

[0048] The first calculation unit is used to calculate the frequency regulation power withdrawn by the demand side in the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side in the power system at the time t+Δt;

[0049] The second calculation unit is used to determine whether the difference between the frequency regulation power withdrawn by the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side of the power system at the time t+Δt is 0, and if so, terminate the operation; if not, calculate the feedforward power of the power system at the current time t based on the frequency regulation power expected to be withdrawn by the demand side of the power system at the time t+Δt;

[0050] Where Δt is the response time difference between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system.

[0051] Furthermore, the first computing unit is configured to:

[0052] The frequency regulation power P withdrawn by the demand side in the power system at the current time t is determined as follows: DDRL,t :

[0053]

[0054] Where, P DDRM The demand-side frequency regulation power before the dynamic demand response resource of the power system is withdrawn; f t is the frequency of the power system at the current moment t;

[0055] The frequency regulation power P expected to be withdrawn on the demand side of the power system at time t+Δt is determined by the following formula: DDRL,t+Δt :

[0056]

[0057] Where, f t+Δt is the frequency of the power system at time t+Δt;

[0058] The frequency f of the power system at time t+Δt is determined as follows: t+Δt :

[0059] f t+Δt =f t +Δt(f t '+αP DDR )

[0060] Where, f t ' is the derivative of the frequency of the power system at the current time t; α is the frequency coefficient of the power system; P DDR is the demand-side frequency regulation power of the power system at the current moment t.

[0061] The demand-side frequency regulation power P of the power system at the current moment t is determined as follows: DDR :

[0062] P DDR (t) = P DDRM -P DDRL,t

[0063] Where, P DDRM It is the demand-side frequency regulation power before the dynamic demand response resources of the power system are withdrawn.

[0064] Furthermore, the calculation of the feedforward power of the power system at the current time t according to the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt includes:

[0065] The feedforward power P of the power system at the current time t is determined as follows: FF (t):

[0066]

[0067] Where K f is the static amplification factor in the demand side transfer function; K0 is the static amplification factor in the power generation side transfer function; P DDRL,t+Δt is the frequency regulation power expected to be withdrawn on the demand side of the power system at time t+Δt.

[0068] Furthermore, the response time difference Δt between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system is determined as follows:

[0069] Δt=4.75T t -4T d

[0070] Where, T t is the time constant of the turbine; T d is the response time constant on the demand side.

[0071] Preferably, the adjustment module is used to:

[0072] Determine the active power P of the power system at the current time t by the following formula: t :

[0073] P t =[ΔP S (t)-ΔP P (t)+P FF (t)]·H1(s)+P DDR (t)·H2(s)-ΔP L

[0074] Where ΔP S (t) is the secondary frequency regulation power on the power generation side of the power system at the current time t; ΔP P (t) is the primary frequency regulation power of the power generation side of the power system at the current time t; P FF (t) is the feedforward power of the power system at the current moment t; H1(s) is the transfer function of the power system generation side; P DDR (t) is the demand-side frequency regulation power of the power system at the current time t; H2(s) is the demand-side transfer function of the power system; ΔP L is the self-disturbance power of the power system;

[0075] The power system generation side transfer function H1(s) is determined as follows:

[0076]

[0077] Where s is the Laplace operator; K0 is the static amplification factor in the transfer function on the power generation side; T g is the time constant of the speed regulator; T t is the time constant of the turbine;

[0078] The power system demand side transfer function H2(s) is determined as follows:

[0079]

[0080] Where K f is the static amplification coefficient in the demand side transfer function; T d is the response time constant on the demand side.

[0081] Compared with the closest prior art, the present invention has the following beneficial effects:

[0082] The technical solution provided by the present invention determines the feedforward power of the power system according to the frequency regulation power withdrawn on the demand side of the power system; adjusts the active power of the power system according to the feedforward power of the power system; and mobilizes the power generation side resources in advance through the feedforward control method when the dynamic demand response resources are withdrawn, and provides active power compensation for the power system. The advantage of reducing the maximum deviation of the grid frequency brought about by the addition of dynamic demand response resources can be retained, while shortening the power system frequency recovery time extended by the continuous withdrawal of dynamic demand response resources, reducing the frequency drop caused by the withdrawal of dynamic demand response resources, and enhancing the stability performance of the power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 This is a block diagram of the dynamic demand response resources participating in power system frequency control when feedforward control is not added;

[0084] Figure 2 This is a block diagram of dynamic demand response resources participating in power system frequency control when feedforward control is added;

[0085] Figure 3 A flow chart of a method for controlling active power of an electric power system for weakening disturbances;

[0086] Figure 4 It is a schematic diagram of the simulation results of the present invention;

[0087] Figure 5 The present invention is a structural diagram of an active power control system of an electric power system for weakening disturbances. DETAILED DESCRIPTION

[0088] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0089] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0090] Traditional power system frequency regulation methods such as Figure 1 As shown in the figure, the frequency regulation methods of the power system include primary frequency regulation and secondary frequency regulation on the generation side, and dynamic demand response resource frequency regulation on the demand side. Primary frequency regulation is regulated by the automatic speed regulation system installed on the generator set, and secondary frequency regulation is achieved by calculating ACE and adjusting the output of each generator according to a certain strategy. The calculation formula of ACE is generally:

[0091] ACE=ΔP Tie -10B·Δf (1)

[0092] Where ΔP Tie is the deviation between the actual transmission power of the control area tie line and the planned value, with output being positive and input being negative; B is the frequency response coefficient of the system control area, which is a negative value (MW / 0.1Hz); Δf is the deviation between the actual system frequency and the rated frequency; ΔP S (t) is the secondary frequency regulation power on the power generation side of the power system at the current time t; ΔP P (t) is the primary frequency regulation power of the power generation side of the power system at the current time t; P DDR (t) is the demand-side frequency regulation power of the power system at the current time t;

[0093] This method can contribute to reducing the maximum frequency deviation of the system under conditions such as large power shortages and improving system stability when dynamic demand response participates in the frequency control of the power system. However, when dynamic demand response resources are withdrawn, it will cause disturbances to the power system and aggravate the active power imbalance of the system.

[0094] Unlike the unpredictability of daily disturbances in the power system, the frequency modulation power withdrawn by the demand side of the power system is predetermined, and this disturbance can be considered known. In this regard, the present invention provides a power system active power control method that reduces the disturbance caused by the withdrawal of dynamic demand response resources. The control principle block diagram is shown in FIG. Figure 2 As shown, in Figure 1A feedforward compensator is added to the control block diagram shown. For power system disturbances caused by the withdrawal of dynamic demand response resources, the frequency regulation resources can be mobilized in advance through the feedforward control method. When the dynamic demand response resources are withdrawn, active power compensation (feedforward power) is provided to the power system, so that the active power of the power system is balanced and the stability of the power system is maintained.

[0095] The flow chart of this method is as follows Figure 3 As shown, the method includes:

[0096] Step 101: Determine the feedforward power of the power system according to the frequency regulation power withdrawn from the demand side of the power system;

[0097] Step 102: Regulate the active power of the power system according to the feedforward power of the power system.

[0098] Specifically, step 101 includes:

[0099] Calculate the frequency regulation power withdrawn from the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn from the demand side of the power system at the time t+Δt;

[0100] Determine whether the difference between the frequency regulation power withdrawn by the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side of the power system at the time t+Δt is 0. If so, end the operation. This indicates that the power system has not withdrawn the dynamic demand response frequency regulation resources at the current time t and the time t+Δt, that is, there is no need to require the power system to provide additional active power compensation (feedforward power)

[0101] If not, the feedforward power of the power system at the current time t is calculated based on the frequency regulation power expected to be withdrawn on the demand side of the power system at time t+Δt;

[0102] Where Δt is the response time difference between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system.

[0103] Furthermore, the calculation of the frequency regulation power withdrawn by the demand side in the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side in the power system at the time t+Δt includes:

[0104] The frequency regulation power P withdrawn by the demand side in the power system at the current time t is determined as follows: DDRL,t :

[0105]

[0106] Where, P DDRM The demand-side frequency regulation power before the dynamic demand response resource of the power system is withdrawn; f t is the frequency of the power system at the current moment t;

[0107] The withdrawal of dynamic demand response resources is carried out in steps until all dynamic demand response resources are completely withdrawn; the dispatching system monitors the frequency changes of the system and the withdrawal of dynamic demand response resources at regular intervals.

[0108] The frequency regulation power P expected to be withdrawn on the demand side of the power system at time t+Δt is determined by the following formula: DDRL,t+Δt :

[0109]

[0110] Where, f t+Δt is the frequency of the power system at time t+Δt;

[0111] The frequency f of the power system at time t+Δt is determined as follows: t+Δt :

[0112] f t+Δt =f t +Δt(f t '+αP DDR )

[0113] Where, f t ' is the derivative of the frequency of the power system at the current time t; α is the frequency coefficient of the power system; P DDR is the demand-side frequency regulation power of the power system at the current moment t.

[0114] The demand-side frequency regulation power P of the power system at the current moment t is determined as follows: DDR :

[0115] P DDR (t) = P DDRM -P DDRL,t

[0116] Where, P DDRM It is the demand-side frequency regulation power before the dynamic demand response resources of the power system are withdrawn.

[0117] Furthermore, the calculation of the feedforward power of the power system at the current time t according to the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt includes:

[0118] The feedforward power P of the power system at the current time t is determined as follows: FF (t):

[0119]

[0120] Where K f is the static amplification factor in the demand side transfer function; K0 is the static amplification factor in the power generation side transfer function; P DDRL,t+Δtis the frequency regulation power expected to be withdrawn on the demand side of the power system at time t+Δt.

[0121] Specifically, the response time difference Δt between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system is determined as follows:

[0122] Δt=4.75T t -4T d

[0123] Where, T t is the time constant of the turbine; T d is the response time constant on the demand side.

[0124] Specifically, step 102 includes:

[0125] Determine the active power P of the power system at the current time t by the following formula: t :

[0126] P t =[ΔP S (t)-ΔP P (t)+P FF (t)]·H1(s)+P DDR (t)·H2(s)-ΔP L

[0127] Where ΔP S (t) is the secondary frequency regulation power on the power generation side of the power system at the current time t; ΔP P (t) is the primary frequency regulation power of the power generation side of the power system at the current time t; P FF (t) is the feedforward power of the power system at the current moment t; H1(s) is the transfer function of the power system generation side; P DDR (t) is the demand-side frequency regulation power of the power system at the current time t; H2(s) is the demand-side transfer function of the power system; ΔP L is the self-disturbance power of the power system;

[0128] The power system generation side transfer function H1(s) is determined as follows:

[0129]

[0130] Where s is the Laplace operator; K0 is the static amplification factor in the transfer function on the power generation side, with a typical value of 1; T g is the time constant of the speed regulator, with a typical value of 0.2; T t is the time constant of the turbine, with a typical value of 0.3;

[0131] The power system demand side transfer function H2(s) is determined as follows:

[0132]

[0133] Where K f is the static amplification factor in the demand side transfer function, with a typical value of 1; T d is the response time constant on the demand side, with a typical value of 0.3.

[0134] like Figure 4 As shown in the figure, it is a schematic diagram of the withdrawal of dynamic demand response resources at a certain node in the system. It can be seen from the figure that in the power system without the addition of a feedforward compensator, the frequency change of the power grid is aggravated after the dynamic demand response resources are withdrawn; in the power system with the addition of a feedforward compensator, the frequency change of the power grid can be slowed down after the dynamic demand response resources are withdrawn.

[0135] The present invention provides an active power control system for a power system for weakening disturbances, such as Figure 5 As shown, the system includes:

[0136] A determination module, configured to determine the feedforward power of the power system according to the frequency regulation power withdrawn from the demand side of the power system;

[0137] The regulating module is used to regulate the active power of the power system according to the feedforward power of the power system.

[0138] Specifically, the determination module includes:

[0139] The first calculation unit is used to calculate the frequency regulation power withdrawn by the demand side in the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side in the power system at the time t+Δt;

[0140] The second calculation unit is used to determine whether the difference between the frequency regulation power withdrawn by the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side of the power system at the time t+Δt is 0, and if so, terminate the operation; if not, calculate the feedforward power of the power system at the current time t based on the frequency regulation power expected to be withdrawn by the demand side of the power system at the time t+Δt;

[0141] Where Δt is the response time difference between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system.

[0142] Specifically, the first computing unit is configured to:

[0143] The frequency regulation power P withdrawn by the demand side in the power system at the current time t is determined as follows: DDRL,t :

[0144]

[0145] Where, P DDRMThe demand-side frequency regulation power before the dynamic demand response resource of the power system is withdrawn; f t is the frequency of the power system at the current moment t;

[0146] The frequency regulation power P expected to be withdrawn on the demand side of the power system at time t+Δt is determined by the following formula: DDRL,t+Δt :

[0147]

[0148] Where, f t+Δt is the frequency of the power system at time t+Δt;

[0149] The frequency f of the power system at time t+Δt is determined as follows: t+Δt :

[0150] f t+Δt =f t +Δt(f t '+αP DDR )

[0151] Where, f t ' is the derivative of the frequency of the power system at the current time t; α is the frequency coefficient of the power system; P DDR is the demand-side frequency regulation power of the power system at the current moment t.

[0152] The demand-side frequency regulation power P of the power system at the current moment t is determined as follows: DDR :

[0153] P DDR (t) = P DDRM -P DDRL,t

[0154] Where, P DDRM It is the demand-side frequency regulation power before the dynamic demand response resources of the power system are withdrawn.

[0155] Specifically, the calculation of the feedforward power of the power system at the current time t according to the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt includes:

[0156] The feedforward power P of the power system at the current time t is determined as follows: FF (t):

[0157]

[0158] Where K f is the static amplification factor in the demand side transfer function; K0 is the static amplification factor in the power generation side transfer function; P DDRL,t+Δt is the frequency regulation power expected to be withdrawn on the demand side of the power system at time t+Δt.

[0159] Specifically, the response time difference Δt between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system is determined as follows:

[0160] Δt=4.75T t -4T d

[0161] Where, T t is the time constant of the turbine; T d is the response time constant on the demand side.

[0162] Specifically, the adjustment module is used to:

[0163] Determine the active power P of the power system at the current time t by the following formula: t :

[0164] P t =[ΔP S (t)-ΔP P (t)+P FF (t)]·H1(s)+P DDR (t)·H2(s)-ΔP L

[0165] Where ΔP S (t) is the secondary frequency regulation power on the power generation side of the power system at the current time t; ΔP P (t) is the primary frequency regulation power of the power generation side of the power system at the current time t; P FF (t) is the feedforward power of the power system at the current moment t; H1(s) is the transfer function of the power system generation side; P DDR (t) is the demand-side frequency regulation power of the power system at the current time t; H2(s) is the demand-side transfer function of the power system; ΔP L is the self-disturbance power of the power system;

[0166] The power system generation side transfer function H1(s) is determined as follows:

[0167]

[0168] Where s is the Laplace operator; K0 is the static amplification factor in the transfer function on the power generation side; T g is the time constant of the speed regulator; T t is the time constant of the turbine;

[0169] The power system demand side transfer function H2(S) is determined as follows:

[0170]

[0171] Where K fis the static amplification coefficient in the demand side transfer function; T d is the response time constant on the demand side.

[0172] 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 a complete hardware embodiment, a complete software embodiment, or an embodiment 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 magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0173] 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 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 steps in the process. 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.

[0174] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work 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 The function specified in one or more boxes.

[0175] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0176] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A method for controlling active power of an electric power system for weakening disturbances, characterized in that: The method comprises: Determine the feedforward power of the power system based on the frequency regulation power withdrawn from the demand side of the power system; regulating the active power of the power system according to the feedforward power of the power system; The determining of the feedforward power of the power system according to the frequency regulation power withdrawn from the demand side of the power system includes: Calculate the frequency regulation power withdrawn from the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn from the demand side of the power system at the time t+Δt; Determine whether the difference between the frequency regulation power withdrawn on the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt is 0. If so, end the operation; if not, calculate the feedforward power of the power system at the current time t based on the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt; Where Δt is the response time difference between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system; The calculation of the frequency regulation power withdrawn by the demand side in the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side in the power system at the time t+Δt includes: The frequency regulation power P withdrawn by the demand side in the power system at the current time t is determined as follows: DDRL,t : Where, P DDRM The demand-side frequency regulation power before the dynamic demand response resource of the power system is withdrawn; f t is the frequency of the power system at the current moment t; The frequency regulation power P expected to be withdrawn on the demand side of the power system at time t+Δt is determined by the following formula: DDRL,t+Δt : Where, f t+Δt is the frequency of the power system at time t+Δt; The frequency f of the power system at time t+Δt is determined as follows: t+Δt : f t+Δt =f t +Δt(f t '+αP DDR ) Where, f t ' is the derivative of the frequency of the power system at the current time t; α is the frequency coefficient of the power system; P DDR is the demand-side frequency regulation power of the power system at the current moment t; The demand-side frequency regulation power P of the power system at the current moment t is determined as follows: DDR : P DDR (t)=P DDRM -P DDRL,t Where, P DDRM It is the demand-side frequency regulation power before the dynamic demand response resources of the power system are withdrawn.

2. The method according to claim 1, wherein The calculating of the feedforward power of the power system at the current time t according to the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt includes: The feedforward power P of the power system at the current time t is determined as follows: FF (t): Where K f is the static amplification factor in the demand side transfer function; K0 is the static amplification factor in the power generation side transfer function; P DDRL,t+Δt is the frequency regulation power expected to be withdrawn on the demand side of the power system at time t+Δt.

3. The method according to claim 1, wherein The response time difference Δt between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system is determined by the following formula: Δt=4.75T t -4T d Where, T t is the time constant of the turbine; T d is the response time constant on the demand side.

4. The method according to claim 1, wherein The adjusting the active power of the power system according to the feedforward power of the power system includes: Determine the active power P of the power system at the current time t by the following formula: t : P t =[ΔP S (t)-ΔP P (t)+P FF (t)]·H1(s)+P DDR (t)·H2(s)-ΔP L Where ΔP S (t) is the secondary frequency regulation power on the power generation side of the power system at the current time t; ΔP P (t) is the primary frequency regulation power of the power generation side of the power system at the current time t; P FF (t) is the feedforward power of the power system at the current moment t; H1(s) is the transfer function of the power system generation side; P DDR (t) is the demand-side frequency regulation power of the power system at the current time t; H2(s) is the demand-side transfer function of the power system; ΔP L is the self-disturbance power of the power system; The power system generation side transfer function H1(s) is determined as follows: Where s is the Laplace operator; K0 is the static amplification factor in the transfer function on the power generation side; T g is the time constant of the speed regulator; T t is the time constant of the turbine; The power system demand side transfer function H2(s) is determined as follows: Where K f is the static amplification coefficient in the demand side transfer function; T d is the response time constant on the demand side.

5. An active power control system for a power system for weakening disturbances, characterized in that: The system comprises: A determination module, configured to determine the feedforward power of the power system according to the frequency regulation power withdrawn from the demand side of the power system; a regulating module, configured to regulate the active power of the power system according to the feedforward power of the power system; The determining module includes: The first calculation unit is used to calculate the frequency regulation power withdrawn by the demand side in the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side in the power system at the time t+Δt; The second calculation unit is used to determine whether the difference between the frequency regulation power withdrawn by the demand side of the power system at the current time t and the frequency regulation power expected to be withdrawn by the demand side of the power system at the time t+Δt is 0, and if so, terminate the operation; if not, calculate the feedforward power of the power system at the current time t based on the frequency regulation power expected to be withdrawn by the demand side of the power system at the time t+Δt; Where Δt is the response time difference between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system; The first computing unit is configured to: The frequency regulation power P withdrawn by the demand side in the power system at the current time t is determined as follows: DDRL,t : Where, P DDRM The demand-side frequency regulation power before the dynamic demand response resource of the power system is withdrawn; f t is the frequency of the power system at the current moment t; The frequency regulation power P expected to be withdrawn on the demand side of the power system at time t+Δt is determined by the following formula: DDRL,t+Δt : Where, f t+Δt is the frequency of the power system at time t+Δt; The frequency f of the power system at time t+Δt is determined as follows: t+Δt : f t+Δt =f t +Δt(f t '+αP DDR ) Where, f t ' is the derivative of the frequency of the power system at the current time t; α is the frequency coefficient of the power system; P DDR is the demand-side frequency regulation power of the power system at the current moment t; The demand-side frequency regulation power P of the power system at the current moment t is determined as follows: DDR : P DDR (t)=P DDRM -P DDRL,t Where, P DDRM It is the demand-side frequency regulation power before the dynamic demand response resources of the power system are withdrawn.

6. The system according to claim 5, wherein: The calculating of the feedforward power of the power system at the current time t according to the frequency regulation power expected to be withdrawn on the demand side of the power system at the time t+Δt includes: The feedforward power P of the power system at the current time t is determined as follows: FF (t): Where K f is the static amplification factor in the demand side transfer function; K0 is the static amplification factor in the power generation side transfer function; P DDRL,t+Δt is the frequency regulation power expected to be withdrawn on the demand side of the power system at time t+Δt.

7. The system according to claim 5, wherein: The response time difference Δt between the frequency regulation on the generation side and the frequency regulation on the demand side in the power system is determined by the following formula: Δt=4.75T t -4T d Where, T t is the time constant of the turbine; T d is the response time constant on the demand side.

8. The system according to claim 5, wherein: The adjustment module is used to: Determine the active power P of the power system at the current time t by the following formula: t : P t =[ΔP S (t)-ΔP P (t)+P FF (t)]·H1(s)+P DDR (t)·H2(s)-ΔP L Where ΔP S (t) is the secondary frequency regulation power on the power generation side of the power system at the current time t; ΔP P (t) is the primary frequency regulation power of the power generation side of the power system at the current time t; P FF (t) is the feedforward power of the power system at the current moment t; H1(s) is the transfer function of the power system generation side; P DDR (t) is the demand-side frequency regulation power of the power system at the current time t; H2(s) is the demand-side transfer function of the power system; ΔP L is the self-disturbance power of the power system; The power system generation side transfer function H1(s) is determined as follows: Where s is the Laplace operator; K0 is the static amplification factor in the transfer function on the power generation side; T g is the time constant of the speed regulator; T t is the time constant of the turbine; The power system demand side transfer function H2(s) is determined as follows: Where K f is the static amplification coefficient in the demand side transfer function; T d is the response time constant on the demand side.

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