Power plant and load-responsive positive damping frequency modulation control method, system and device

Abstract

The present invention relates to the field of automatic control technology, and specifically to a positive damping frequency modulation control method, system and equipment for power plants and response loads. The present method is for power generation of hydropower, thermal power, photovoltaic, wind power and other power plants connected to the grid, and frequency modulation participated in by response loads on the grid demand side such as electrolytic aluminum and charging stations, and proposes a positive damping primary frequency modulation and AGC superimposed frequency modulation control. By superimposing the load instruction and the final value of the primary frequency modulation positive damping instruction, a frequency modulation control method that meets the stable operation of the current and future new power systems is formed; the primary frequency modulation load initial value required by the grid is formed after the positive damping unit negative feedback PID control. The present invention uses the operating parameters of the power plant to control the load and frequency of the power plant network through the positive damping stable and fast control method, which solves potential major safety and stability problems, has the simplicity and economy of implementation, and plays an important basic supporting role in the safety and stability of the power plant network operation.

Description

Technical Field

[0001] The present invention relates to the field of automatic control technology, and in particular to a positive damping frequency modulation control method, system and equipment for a power plant and a response load. Background Art

[0002] Renewable energy plays an increasingly important role in the current development of electricity, especially photovoltaic and wind power generation of new energy, which are developing rapidly in the new power system and gradually becoming the main power generation. They have the advantages of being green, low-carbon, renewable, rich in resources and low cost. With the continuous increase in the proportion of new energy, power plants need to participate in the load frequency control of the power grid. The load control of renewable energy power generation, including hydropower, can respond quickly to the instructions of the power grid AGC, and the primary frequency control on the plant side can also respond quickly. However, the primary frequency regulation of renewable energy in coordination with the frequency control of the power grid presents a negative damping characteristic. With the development of thermal power units in coordination with the new power system and in multiple directions such as energy storage peak regulation and frequency regulation, its load frequency characteristics will also show negative damping characteristics, which will have a great impact on the stability of the power grid frequency control.

[0003] Large-load users such as electrolytic aluminum and electrolytic silicon, including rapidly developing electric vehicle charging stations, will significantly reduce the construction of high-investment energy storage power stations through demand-side load-responsive frequency control. However, these load-responsive frequency controls also show negative damping characteristics that affect the frequency stability of the power grid, and a frequency control strategy that ensures safety and stability is also needed.

[0004] Therefore, in the current and future power systems dominated by a high proportion of renewable energy, a stable frequency regulation control strategy is urgently needed to ensure the safety and stability of grid frequency operation. Summary of the invention

[0005] The purpose of the present invention is to provide a positive damping frequency modulation control method, system and equipment for power plants and responsive loads. The method can provide a positive damping primary frequency modulation control strategy for power plants and responsive loads in power systems, and simultaneously realize the superposition control algorithm of AGC and primary frequency modulation, providing an important solution for participating in frequency modulation and supporting grid load and frequency stability for the rapid development of new energy and high-proportion grid access control.

[0006] To achieve the above-mentioned object, the present invention provides a power plant and a positive damping frequency modulation control method, system and device for responding to loads, and the power plant and the positive damping frequency modulation control method, system and device for responding to loads include the following steps:

[0007] Step 1: Calculate the frequency difference Δf by measuring the high-precision grid frequency f and the rated grid frequency f0, and calculate the primary frequency modulation load instruction P from the frequency difference f2 :

[0008] P f1 =Δf / f0 / δ·P e ·G ON ·T IN ;

[0009] In the above formula, P f1 is the intermediate value calculated for the primary frequency regulation load instruction; Δf is the frequency difference between the grid frequency and the rated frequency excluding the dead zone, which is calculated as f0-f±fz for the power generation unit of the plant and station, and f-f0±f for the demand response load. z , where f z is the frequency dead zone, and the frequency difference is calculated to be 0 in the dead zone; f0 is the rated grid frequency; δ is the primary frequency difference coefficient; P e G is the rated capacity of the generating unit load or the rated capacity of the unit demand load; ON The unit load is connected to the grid; T IN The primary frequency regulation function of the unit load is in operation state;

[0010] P f2 =IF(P f1 ,0,P MIN ≤P f1 ≤P MAX )+IF(P MAX ,0,P f1 >P MAX )+IF(P MIN ,0,P f1 <P MIN );

[0011] In the above formula, P f2 is a frequency modulation load instruction, for P f1 Limit value; P MAX is the upper limit value; P MIN is the lower limit value;

[0012] Step 2: Use the proportional-integral-derivative control with unit negative feedback to calculate the final value P for the positive damping primary frequency modulation load control fc At the same time, the distribution module is used to participate in the distribution, calculate the distribution value of each unit load, and meet the load instruction P of each distribution module export i The summed value is consistent with the allocation input instruction;

[0013] Using unit negative feedback PID, calculate the final value P for positive damping primary frequency modulation load control fc :

[0014] P fc =K p ·DEV+∫DEV / T i ·dt+T d·DEV′;

[0015] In the above formula, P fc It is the final value for primary frequency modulation load control; DEV is the PID deviation input, here it is the frequency modulation load P f2 The difference with PID output value OUTPID: P f2 -OUTPID; K p is the PID proportional coefficient; T i is the PID integration time; T d is the PID differential time; DEV′ is the differential of DEV;

[0016] Using the existing method and the distribution module PAT, the distribution value of each unit load is calculated to satisfy the load instruction P of each distribution module outlet. i , satisfying ∑P i Consistent with the allocation input instruction;

[0017] Step 3: Use unit load instruction P i The command of the unit load i is superimposed with the command of the primary frequency modulation to form the command final value P of the AGC and the primary frequency modulation superimposed. ci and the final control output value O of unit load i pci :

[0018] P ci =P fci +P i ;

[0019] In the above formula, P ci is the command final value of unit load i; P fci is the final value of the primary frequency modulation instruction of unit load i; P i is the assigned load value of unit load i;

[0020] O pci =O fci +O i ;

[0021] In the above formula, O pci is the final value of the control output of unit load i; fci is the feedforward value of the final value of the primary frequency modulation instruction of unit load i, which is equal to K·P fci , K is the feedforward gain coefficient; O i is the final control output value of unit load i;

[0022] Step 4: The calculated instruction final value P corresponding to the unit load i ci And the feedforward value O corresponding to the final value of the frequency modulation instruction fci Send to the corresponding circuit;

[0023] Among them, the feedforward value O corresponding to the final value of the primary frequency modulation instruction fci The specific method of sending to the corresponding circuit is:

[0024] Unit load command final value P for power plant ci , sent to the load control system command loop of the corresponding power generation unit to control the power generation load;

[0025] The feedforward value O of the final value of the primary frequency regulation command of the corresponding power generation unit load fci , sent to the load control system output loop of the corresponding power generation unit for feedforward superposition control;

[0026] Unit load command final value P for demand response load ci , sent to the load control system command loop of the corresponding demand response load unit to perform response load control;

[0027] The corresponding feedforward value O of the final value of the primary frequency regulation instruction of the demand response load unit fci , sent to the response load control system output loop of the corresponding demand response load unit for feedforward superposition control.

[0028] Among them, G ON Indicates whether the unit load is connected to the grid. When it is connected to the grid, G ON is 1 if the value is true, otherwise it is 0.

[0029] Among them, TIN is whether the primary frequency regulation function of the unit load is in the enabled state. When it is in the enabled state, TIN is 1, otherwise it is 0.

[0030] The present invention is generally implemented in a main control DCS control system of a power plant or a response load, or in a PLC system, and can also be implemented by a programmed electronic device with a hardware IO or communication interface. The power plant or response load primary frequency modulation positive damping instruction calculated by the method is sent to the control system for load distribution instruction superposition and load control output instruction feedforward superposition, so as to realize stable and rapid control of load and frequency of the power system.

[0031] The idea of ​​the present invention is that the control functions of the AGC and primary frequency regulation at the power plant or response load side are different. The AGC adjusts each load according to the dispatching load instruction to achieve the load target value according to the principle of rapid and stable operation. The primary frequency regulation assists the AGC in controlling the grid frequency within the required deviation range quickly and stably on site. The primary frequency regulation loop adds a positive damping control loop so that the superposition of the load instruction or control output with the AGC can ensure the stability and rapidity of its grid frequency control. The correctness of the idea of ​​the present invention is verified by establishing a grid load-frequency model to simulate new energy, thermal power, hydropower and response loads. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 It is a block diagram of the positive damping frequency modulation control method of the power plant of the present invention;

[0034] Figure 2 is a block diagram of the load-responsive positive damping frequency modulation control method of the present invention;

[0035] Figure 3 It is a schematic diagram of the control flow of the solution of the present invention;

[0036] Figure 4 It is a schematic diagram of the electronic system equipment of the present invention.

[0037] In the figure: 1001 - first processing module, 1002 - second processing module, 1003 - third processing module, 1004 - transmission and interface module, 2001 - processor, 2002 - memory, 2003 - storage, 2004 - IO interface, 2005 - communication interface. DETAILED DESCRIPTION

[0038] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0039] like Figure 1 As shown, the project is implemented on the load and frequency control system of the power plant station;

[0040] like Figure 2 As shown, the project is implemented on the load and frequency control system on the response load side;

[0041] A power plant and a load-responsive positive damping frequency modulation control method, system and device, comprising the following steps:

[0042] S1: Calculate the frequency difference Δf by measuring the high-precision grid frequency f and the rated grid frequency f0, and calculate the primary frequency regulation load instruction P by the frequency difference f2 :

[0043] The primary frequency modulation load instruction calculates the intermediate value P f1The specific calculation method is:

[0044] P f1 =Δf / f0 / δ·P e ·G ON ·T IN ;

[0045] In the above formula, P f1 is the intermediate value calculated for the primary frequency regulation load instruction; Δf is the frequency difference between the grid frequency and the rated frequency excluding the dead zone, which is calculated as f0-f±fz for the power generation unit of the plant and station, and f-f0±f for the demand response load. z , where f z is the frequency dead zone, and the frequency difference is calculated to be 0 in the dead zone; f0 is the rated grid frequency; δ is the primary frequency difference coefficient; P e G is the rated capacity of the generating unit load or the rated capacity of the unit demand load; ON The unit load is connected to the grid; T IN The primary frequency regulation function of the unit load is in operation state;

[0046] P f2 =IF(P f1 ,0,P MIN ≤P f1 ≤P MAX )+IF(P MAX ,0,P f1 >P MAX )+IF(P MIN ,0,P f1 <P MIN );

[0047] In the above formula, P f2 is a frequency modulation load instruction, for P f1 Limit value; P MAX is the upper limit value; P MIN is the lower limit value;

[0048] S2: Proportional-integral-differential control with unit negative feedback is used to calculate the final value P for the primary frequency modulation load control with positive damping fc At the same time, the distribution module is used to participate in the distribution, calculate the distribution value of each unit load, and meet the load instruction P of each distribution module export i The summed value is consistent with the allocation input instruction;

[0049] Using unit negative feedback PID, calculate the final value P for positive damping primary frequency modulation load control fc At the same time, the existing method and the distribution module PAT are used to calculate the distribution value of each unit load so that it meets the load instruction P of each distribution module export i , which is consistent with the allocation input instruction;

[0050] The final value P of the primary frequency regulation load control fc The specific calculation method is:

[0051] P fc =K p ·DEV+∫DEV / T i ·dt+T d ·DEV′;

[0052] In the above formula, P fc It is the final value for primary frequency modulation load control; DEV is the PID deviation input, here it is the frequency modulation load P f2 The difference with PID output value OUTPID: P f2 -OUTPID; K p is the PID proportional coefficient; T i is the PID integration time; T d is the PID differential time; DEV′ is the differential of DEV;

[0053] S3: Through unit load instruction P i The command of the unit load i is superimposed with the command of the primary frequency modulation to form the command final value P of the AGC and the primary frequency modulation superimposed. ci and the final control output value O of unit load i pci ;

[0054] By superimposing the unit load command and the primary frequency modulation command, the final value of the AGC and primary frequency modulation superimposed control load command and the final value of the control output feedforward command are formed:

[0055] The specific calculation method of the command final value and the control output final value is:

[0056] P ci =P fci +P i ;

[0057] In the above formula, P ci is the command final value of unit load i; P fci is the final value of the primary frequency modulation instruction of unit load i; P i is the assigned load value of unit load i;

[0058] O pci =O fci +O i ;

[0059] In the above formula, O pci is the final value of the control output of unit load i; fci is the feedforward value of the final value of the primary frequency modulation instruction of unit load i, which is equal to K·P fci, K is the feedforward gain coefficient; O i is the final control output value of unit load i;

[0060] S4: The calculated unit load i command final value P ci And the feedforward value O corresponding to the final value of the frequency modulation instruction fci Send to the corresponding circuit;

[0061] The corresponding unit load instruction final value P ci And the feedforward value O corresponding to the final value of the frequency modulation instruction fci The specific method of sending to the corresponding circuit is:

[0062] Unit load command final value P for power plant ci , sent to the load control system command loop of the corresponding power generation unit to control the power generation load;

[0063] The feedforward value O of the final value of the primary frequency regulation command of the corresponding power generation unit load fci , sent to the load control system output loop of the corresponding power generation unit for feedforward superposition control;

[0064] Unit load command final value P for demand response load ci , sent to the load control system command loop of the corresponding demand response load unit to perform response load control;

[0065] The corresponding feedforward value O of the final value of the primary frequency regulation instruction of the demand response load unit fci , sent to the response load control system output loop of the corresponding demand response load unit for feedforward superposition control.

[0066] Furthermore, G ON Indicates whether the unit load is connected to the grid. When it is connected to the grid, G ON is 1 if the value is true, otherwise it is 0.

[0067] Furthermore, T IN It indicates whether the primary frequency regulation function of the unit load is in the enabled state. When it is in the enabled state, T IN is 1 if the value is true, otherwise it is 0.

[0068] It can be implemented in the main control DCS control system of the power plant or the response load, or in the PLC system, or it can be implemented through a programmed electronic device with hardware IO or communication interface. According to the above control algorithm, the logical configuration is modified, the positive damping primary frequency modulation instruction superposition value and the control output feedforward superposition value are calculated, and transmitted to the corresponding unit load instruction superposition and control output superposition. The original related primary frequency modulation control strategy is replaced by this scheme. At the same time, the final value of the positive damping instruction calculation of this primary frequency modulation is displayed on the monitoring system screen to facilitate the monitoring of the operating personnel.

[0069] like Figure 3 As shown, the power plant station and the positive damping frequency modulation control system responsive to the load provided by this solution include:

[0070] The first processing module 1001 is used to calculate the frequency difference Δf by measuring the high-precision grid frequency f and the rated grid frequency f0, and calculate the primary frequency regulation load instruction P from the frequency difference f2 :

[0071] P f1 =Δf / f0 / δ·P e ·G ON ·T IN ;

[0072] In the above formula, P f1 is the intermediate value calculated for the primary frequency regulation load instruction; Δf is the frequency difference between the grid frequency and the rated frequency excluding the dead zone, which is calculated as f0-f±fz for the power generation unit of the plant and station, and f-f0±f for the demand response load. z , where f z is the frequency dead zone, and the frequency difference is calculated to be 0 in the dead zone; f0 is the rated grid frequency; δ is the primary frequency difference coefficient; P e G is the rated capacity of the generating unit load or the rated capacity of the unit demand load; ON The unit load is connected to the grid; T IN The primary frequency regulation function of the unit load is in operation state;

[0073] P f2 =IF(P f1 ,0,P MIN ≤P f1 ≤P MAX )+IF(P MAX ,0,P f1 >P MAX )+IF(P MIN ,0,P f1 <P MIN );

[0074] In the above formula, P f2 is a frequency modulation load instruction, for Pf1 Limit value; P MAX is the upper limit value; P MIN is the lower limit value;

[0075] The second processing module 1002 uses the unit negative feedback PID to calculate the final value P for the primary frequency modulation load control of the positive damping fc :

[0076] P fc =K p ·DEV+∫DEV / T i ·dt+T d ·DEV′;

[0077] In the above formula, P fc It is the final value for primary frequency modulation load control; DEV is the PID deviation input, here it is the frequency modulation load P f2 The difference with PID output value OUTPID: P f2 -OUTPID; K p is the PID proportional coefficient; T i is the PID integration time; T d is the PID differential time; DEV′ is the differential of DEV;

[0078] Using the existing method and the distribution module PAT, the distribution value of each unit load is calculated to satisfy the load instruction P of each distribution module outlet. i The summed value is consistent with the allocation input instruction;

[0079] The third processing module 1003 forms a final value of the AGC and primary frequency modulation superimposed control load instruction and a final value of the control output feedforward instruction by superimposing the unit load instruction and the primary frequency modulation instruction:

[0080] P ci =P fci +P i ;

[0081] In the above formula, P ci is the command final value of unit load i; P fci is the final value of the primary frequency modulation instruction of unit load i; P i is the assigned load value of unit load i;

[0082] O pci =O fci +O i ;

[0083] In the above formula, O pci is the final value of the control output of unit load i; fci is the feedforward value of the final value of the primary frequency modulation instruction of unit load i, which is equal to K·Pfci , K is the feedforward gain coefficient; O i is the final control output value of unit load i;

[0084] The fourth processing module 1004 is for the unit load instruction final value P of the power plant station. ci , sent to the load control system command loop of the corresponding power generation unit for power generation load control; the feedforward value of the primary frequency regulation command final value of the corresponding power generation unit load is O fci , and sent to the load control system output loop of the corresponding power generation unit for feedforward superposition control.

[0085] Unit load command final value P for demand response load ci , sent to the load control system command loop of the corresponding demand response load unit for response load control; the feedforward value O of the final value of the primary frequency modulation command of the corresponding demand response load unit fci , sent to the response load control system output loop of the corresponding demand response load unit for feedforward superposition control.

[0086] The system provided in the embodiment of the present invention is used to execute the above-mentioned method embodiments. Please refer to the above-mentioned embodiments for the specific process and detailed contents, which will not be repeated here.

[0087] Figure 4 2 is a schematic diagram of the structure of an electronic system device according to an embodiment of the present invention. The electronic device may include: a processor 2001, a memory 2002, a storage 2003, an IO interface 2004, and a communication interface 2005. The processor 2001, the IO interface 2004, the communication interface 2005, and the storage 2003 communicate with each other through a system bus. The processor 2001 may call the logic instructions in the memory 2002 and the storage 2003 to execute the following method:

[0088] Step 1: Calculate the frequency difference Δf by measuring the high-precision grid frequency f and the rated grid frequency f0, and calculate the primary frequency regulation load instruction P from the frequency difference f2 :

[0089] P f1 =Δf / f0 / δ·P e ·G ON ·T IN ;

[0090] In the above formula, P f1 is the intermediate value calculated for the primary frequency regulation load instruction; Δf is the frequency difference between the grid frequency and the rated frequency excluding the dead zone, which is calculated as f0-f±fz for the power generation unit of the plant and station, and f-f0±f for the demand response load. z , where f zis the frequency dead zone, and the frequency difference is calculated to be 0 in the dead zone; f0 is the rated grid frequency; δ is the primary frequency difference coefficient; P e G is the rated capacity of the generating unit load or the rated capacity of the unit demand load; ON The unit load is connected to the grid; T IN The primary frequency regulation function of the unit load is in operation state;

[0091] P f2 =IF(P f1 ,0,P MIN ≤P f1 ≤P MAX )+IF(P MAX ,0,P f1 >P MAX )+IF(P MIN ,0,P f1 <P MIN );

[0092] In the above formula, P f2 is a frequency modulation load instruction, for P f1 Limit value; P MAX is the upper limit value; P MIN is the lower limit value;

[0093] Step 2: Use the proportional-integral-differential control with unit negative feedback to calculate the final value P for the primary frequency modulation load control with positive damping. fc At the same time, the distribution module is used to participate in the distribution, calculate the distribution value of each unit load, and meet the load instruction P of each distribution module export i The summed value is consistent with the allocation input instruction;

[0094] Using unit negative feedback PID, calculate the final value P for positive damping primary frequency modulation load control fc :

[0095] P fc =K p ·DEV+∫DEV / T i ·dt+T d ·DEV′;

[0096] In the above formula, P fc It is the final value for primary frequency modulation load control; DEV is the PID deviation input, here it is the frequency modulation load P f2 The difference with PID output value OUTPID: P f2 -OUTPID; K p is the PID proportional coefficient; T i is the PID integration time; T d is the PID differential time; DEV′ is the differential of DEV;

[0097] Using the existing method and the distribution module PAT, the distribution value of each unit load is calculated to satisfy the load instruction P of each distribution module outlet. i The summed value is consistent with the allocation input instruction;

[0098] Step 3: Use unit load instruction P i The command of the unit load i is superimposed with the command of the primary frequency modulation to form the command final value P of the AGC and the primary frequency modulation superimposed. ci and the final control output value O of unit load i pci ;

[0099] By superimposing the unit load command and the primary frequency modulation command, the final value of the control load command and the final value of the control output feedforward command superimposed by AGC and primary frequency modulation are formed:

[0100] P ci =P fci +P i ;

[0101] In the above formula, P ci is the command final value of unit load i; P fci is the final value of the primary frequency modulation instruction of unit load i; P i is the assigned load value of unit load i;

[0102] O pci =O fci +O i ;

[0103] In the above formula, O pci is the final value of the control output of unit load i; fci is the feedforward value of the final value of the primary frequency modulation instruction of unit load i, which is equal to K·P fci , K is the feedforward gain coefficient; O i is the final control output value of unit load i;

[0104] Step 4: calculate the final value P of the instruction corresponding to the unit load i ci And the feedforward value O corresponding to the final value of the frequency modulation instruction fci Send to the corresponding circuit;

[0105] Unit load command final value P for power plant ci , sent to the load control system command loop of the corresponding power generation unit to control the power generation load;

[0106] Step 5: The feedforward value O of the final value of the primary frequency regulation command of the corresponding power generation unit load fci , sent to the load control system output loop of the corresponding power generation unit for feedforward superposition control;

[0107] Step 6: Unit load instruction final value P for demand response load ci , sent to the load control system command loop of the corresponding demand response load unit to perform response load control;

[0108] Step 7: The feedforward value O of the final value of the primary frequency regulation instruction of the corresponding demand response load unit fci , sent to the response load control system output loop of the corresponding demand response load unit for feedforward superposition control.

[0109] In addition, the logic instructions in the above-mentioned memory 2003 can be implemented in the form of software functional units and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on such an understanding, the technical solution of the present invention can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, an embedded computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0110] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0111] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, or of course by hardware. Based on this understanding, the above technical solution, in essence or in other words, the part that contributes to the prior art, can be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for a computer device to execute the methods described in each embodiment or some parts of the embodiments.

[0112] The basic principles, main features and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which shall fall within the scope of the present invention to be protected. The scope of protection of the present invention shall be defined by the attached claims and their equivalents.

Claims

1. A power plant and a positive damping frequency modulation control method for a responsive load, characterized in that: The following steps are involved: The frequency difference Δf is calculated by measuring the high-precision grid frequency f and the rated grid frequency f0, and the primary frequency regulation load instruction P is calculated by the frequency difference f2 ; Using the proportional-integral-differential control with unit negative feedback, calculate the final value P for the primary frequency modulation load control with positive damping fc At the same time, the distribution module is used to participate in the distribution, calculate the distribution value of each unit load, and meet the load instruction P of each distribution module export i The summed value is consistent with the allocation input instruction; By unit load instruction P i The command of the unit load i is superimposed with the command of the primary frequency modulation to form the command final value P of the AGC and the primary frequency modulation superimposed. ci and the final control output value O of unit load i pci , the specific calculation method of the command final value of the unit load i and the control output final value of the unit load i is: P ci =P fci +P i ; In the above formula, P ci is the command final value of unit load i; P fci is the final value of the primary frequency modulation instruction of unit load i; P i is the assigned load value of unit load i; The pci =O fci +O i ; In the above formula, O pci is the final value of the control output of unit load i; fci is the feedforward value of the final value of the primary frequency modulation instruction of unit load i, which is equal to K·P fci , K is the feedforward gain coefficient; O i is the final control output value of unit load i; The calculated command final value P of the corresponding unit load i ci And the feedforward value O corresponding to the final value of the frequency modulation instruction fci Send to the corresponding circuit.

2. The power plant and the load-responsive positive damping frequency modulation control method according to claim 1, characterized in that: in, The intermediate value P of the primary frequency regulation load instruction calculation f1 The specific calculation method is: P f1 =Δf / f0 / δ·P e ·G ON ·T IN ; In the above formula, P f1 is the intermediate value of the primary frequency regulation load instruction calculation; Δf is the frequency difference between the grid frequency and the rated frequency excluding the dead zone, which is calculated as f0-f±f for the power generation unit of the plant z , for demand response load calculation is f-f0±f z , where f z is the frequency dead zone, and the frequency difference is calculated to be 0 in the dead zone; f0 is the rated grid frequency; δ is the primary frequency difference coefficient; P e G is the rated capacity of the generating unit load or the rated capacity of the unit demand load; ON The unit load is connected to the grid; T IN The primary frequency regulation function of the unit load is in operation state; The primary frequency modulation load instruction P f2 The specific calculation method is: P f2 =IF(P f1 ,0,P MIN ≤P f1 ≤P MAX )+IF(P MAX ,0,P f1 >P MAX )+IF(P MIN ,0,P f1 <P MIN ); In the above formula, P f2 is a frequency modulation load instruction, for P f1 Limit value; P MAX is the upper limit value; P MIN The lower limit value.

3. The power plant and the load-responsive positive damping frequency modulation control method according to claim 2, characterized in that: The final value P of the primary frequency regulation load control fc The specific calculation method is: P fc =K p ·DEV+∫DEV / T i ·dt+T d ·DEV′; In the above formula, P fc It is the final value for primary frequency modulation load control; DEV is the PID deviation input, here it is the frequency modulation load P f2 The difference with PID output value OUTPID: P f2 -OUTPID; K p is the PID proportional coefficient; T i is the PID integration time; T d is the PID differential time; DEV′ is the differential of DEV.

4. The power plant and the load-responsive positive damping frequency modulation control method according to claim 3, characterized in that: The command final value P of the unit load i ci And the feedforward value O corresponding to the final value of the frequency modulation instruction fci The specific method of sending to the corresponding circuit is: Unit load command final value P for power plant ci , sent to the load control system command loop of the corresponding power generation unit to control the power generation load; The feedforward value O of the final value of the primary frequency regulation command of the corresponding power generation unit load fci , sent to the load control system output loop of the corresponding power generation unit for feedforward superposition control; Unit load command final value P for demand response load ci , sent to the load control system command loop of the corresponding demand response load unit to perform response load control; The corresponding feedforward value O of the final value of the primary frequency regulation command of the demand response load unit fci , sent to the response load control system output loop of the corresponding demand response load unit for feedforward superposition control.

5. The power plant and the load-responsive positive damping frequency modulation control method according to claim 2, characterized in that: G ON Indicates whether the unit load is connected to the grid. When it is connected to the grid, G ON is 1 if the value is true, otherwise it is 0.

6. The power plant and the load-responsive positive damping frequency modulation control method according to claim 2, characterized in that: T IN It indicates whether the primary frequency regulation function of the unit load is in the enabled state. When it is in the enabled state, T IN is 1 if the value is true, otherwise it is 0.

7. A power plant and a load-responsive positive damping frequency modulation control system, using the power plant and a load-responsive positive damping frequency modulation control method as claimed in claim 1, characterized in that: comprising a first processing module, a second processing module, a third processing module and a fourth processing module, The first processing module calculates the frequency difference Δf by measuring the high-precision grid frequency f and the rated grid frequency f0, and calculates the primary frequency modulation load instruction P from the frequency difference f2 ; The second processing module uses a unit negative feedback PID to calculate the final value P of the positive damping primary frequency modulation load control fc At the same time, the existing method and the distribution module PAT are used to calculate the distribution value of each unit load to meet the load instruction P of each distribution module export. i The summed value is consistent with the allocation input instruction; The third processing module, through the unit load instruction P i The command of the unit load i is superimposed with the command of the primary frequency modulation to form the command final value P of the AGC and the primary frequency modulation superimposed. ci and the final control output value O of unit load i pci ; The fourth processing module calculates the final value P of the instruction of the unit load i ci And the feedforward value O corresponding to the final value of the frequency modulation instruction fci Send to the corresponding circuit.

8. A computer device, characterized in that: The method comprises a processor, a memory, an IO interface, a communication interface, a storage and a computer program running in the memory, wherein the processor executes the program generated in the memory to implement the steps of the positive damping frequency regulation control method for a power plant and a demand response load as claimed in any one of claims 1 to 4.

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