CN108964089B - Power system load frequency control method and related product - Google Patents

Abstract

The present invention provides a load frequency control method for a power system, comprising: acquiring power error and frequency deviation of a power network; using the power error and the frequency deviation to obtain a control amount by using a full-order sliding mode control method; The control quantity controls the governor of the power station to regulate the load, frequency of the power network. The present invention uses the full-order sliding mode control method to control the governor. Compared with the reduced-order sliding mode control method in the prior art, the sliding mode surface method is full-order. In the frequency load regulation of the power system, Reduce singularity and reduce chattering. The power system load frequency control device, system, computer equipment and computer-readable storage medium provided by the present invention also have the above beneficial effects, which will not be repeated here.

Description

A power system load frequency control method and related products

technical field

The invention relates to the technical field of power system regulation and control, in particular to a power system load frequency control method and related products.

Background technique

With the increase of electricity consumption year by year, people put forward higher and higher requirements for the stability and quality of electric energy. Therefore, load frequency control is one of the important topics in the design and operation of power systems. For the power system, the load is always changing, and various faults may occur at any time. It is necessary to design a load frequency control system, so that the power system can control the load of the generator depending on the frequency; How to control the frequency within an acceptable range is always a very challenging research topic for a certain power system.

The models for load frequency control of the power system in the prior art are all based on linear models, and even if they include nonlinearity, there is only one model. However, in practical systems, the power system is an interconnected, complex, coupled nonlinear system. Therefore, the linear system can not really represent the load frequency control model of the power system, and it becomes very necessary to use the nonlinear model to represent the load frequency control model of the power system. Sliding mode control has the ability to resist external disturbances and parameter changes, so sliding mode control has a large number of applications in nonlinear systems, stochastic systems, power electronics, motors, etc. At home and abroad, sliding mode control is also used in load frequency control of power systems. However, most of the sliding mode surfaces of the sliding mode control based on the load frequency control are reduced-order sliding mode surfaces, and the reduced-order sliding mode surfaces are prone to singularity.

Therefore, how to provide a frequency load control scheme of the power system that can reduce singularity and reduce the degree of chattering in the frequency load regulation of the power system is a technical problem to be solved by those skilled in the art.

SUMMARY OF THE INVENTION

In view of this, the purpose of the present invention is to provide a power system load frequency control method and related products, which can reduce singularity and reduce the degree of chattering in the frequency load regulation of the power system. Its specific plan is as follows:

In a first aspect, the present invention provides a method for controlling load frequency of a power system, including:

Obtain the power error and frequency deviation of the power network;

Using the power error and the frequency deviation, the full-order sliding mode control method is used to calculate the control amount;

The governor of the power station is controlled by the control variable to adjust the load and frequency of the power network.

Preferably,

The full-order sliding mode control method is a full-order terminal sliding mode control method;

The nonlinear equation of the full-order terminal sliding mode control method is:

Wherein, the x is a vector, the f(x, t) and the a(x, t) are both nonlinear equations, the d is an external disturbance, and the u is a control variable;

And the equation of the terminal sliding surface is:

Both β _i and λ _i in the above formula are constants; the selection of β _i makes the solutions of the polynomial p ⁿ +β _n p ^n-1 +β _n-1 p ^n-2 +…β ₂ p+β ₁ all negative ;

The selection of the λ _i refers to the following formula:

Among them, λ _n+1 =1, λ _n =λ, λ∈(0,1);

Let the equation of the terminal sliding surface be equal to zero, the control quantity is obtained:

u=a ^-1 (u _eq +u _n )=u' _eq +u' _n

in,

The u _n is:

Wherein, the v is:

Among them, l is a positive preset coefficient, s is a sliding mode surface equation, and ξ is a preset positive number.

Preferably,

The full-order sliding mode control method is a full-order linear sliding mode control method;

The nonlinear equation of the full-order linear sliding mode control method is:

Wherein, the x is a vector, the f(x, t) and the a(x, t) are both nonlinear equations, the d is an external disturbance, and the u is a control variable;

The equation for the linear sliding surface is:

Both β _i and λ _i in the above formula are constants; the selection of β _i makes the solutions of the polynomial p ⁿ +β _n p ^n-1 +β _n-1 p ^n-2 +…β ₂ p+β ₁ all negative ;

The selection of the λ _i refers to the following formula:

in,

λ _n+1 =1, λ _n =λ, λ∈(0,1);

Set the sliding surface equal to zero to get the control quantity:

u=a ^-1 (u _eq +u _n )=u' _eq +u' _n

in,

u _eq =-f(x,t)-β _n x _n -…-β ₁ x ₁

The u _n is:

Wherein, the v is:

Among them, l is a positive preset coefficient, s is a sliding mode surface equation, and ξ is a preset positive number.

Preferably, the control quantity is limited by two nonlinearities of GDB and/or GRC of the generator.

In a second aspect, the present invention provides a power system load frequency control device, comprising:

The deviation acquisition module is used to obtain the power error and frequency deviation of the power network;

a control quantity calculation module, configured to use the power error and the frequency deviation to calculate the control quantity by adopting a full-order sliding mode control method;

The governor control module is used to control the governor of the power station by using the control quantity, so as to adjust the load and frequency of the power network.

In a third aspect, the present invention provides a power system load frequency control system, which is applied to a power network in which two regions are interconnected, the power network comprising: a first power network and a second power network connected by a tie line;

The first regional power grid is provided with a first load frequency control device, and the second regional power grid is provided with a second load frequency control device;

The first load frequency control device includes:

a first deviation obtaining module, configured to obtain a first power error and a first frequency deviation of the first power network;

a first control quantity calculation module, configured to use the first power error, the first frequency deviation, and the second frequency deviation to calculate the first control quantity by adopting the first full-order sliding mode control method;

a first governor control module, configured to use the first control variable to control the governor of the first power station to adjust the load and frequency of the first power network;

The second load frequency control device includes:

a second deviation obtaining module, configured to obtain the second power error and the second frequency deviation of the second power network;

a second control variable calculation module, configured to use the second power error, the second frequency deviation, and the first frequency deviation to calculate the second control variable by using the second full-order sliding mode control method;

a second governor control module, configured to use the second control variable to control the governor of the second power station to adjust the load and frequency of the second power network;

Preferably, the first full-order sliding mode control method and the second full-order sliding mode control method are both full-order terminal sliding mode control methods.

Preferably, the first full-order sliding mode control method and the second full-order sliding mode control method are both full-order linear sliding mode control methods.

In a fourth aspect, the present invention provides a computer device, comprising:

memory for storing computer programs;

The processor is configured to implement the steps of any one of the power system load frequency control methods described in the first aspect above when executing the computer program.

In a fifth aspect, the present invention provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, implements any one of the power systems described in the first aspect above The steps of the load frequency control method.

The present invention provides a load frequency control method for a power system, comprising: acquiring power error and frequency deviation of a power network; using the power error and the frequency deviation to obtain a control amount by using a full-order sliding mode control method; The control variable controls the governor of the power station to regulate the load, frequency of the power network. The present invention uses the full-order sliding mode control method to control the governor. Compared with the reduced-order sliding mode control method in the prior art, the sliding mode surface method is full-order. In the frequency load regulation of the power system, Reduce singularity and reduce chattering.

The power system load frequency control device, system, computer equipment and computer-readable storage medium provided by the present invention also have the above beneficial effects, which will not be repeated here.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to the provided drawings without creative work.

Fig. 1 is a kind of power system load frequency control method provided by a specific embodiment of the present invention;

FIG. 2 is a schematic diagram of the composition of a power system load frequency control device provided by another specific embodiment of the present invention;

3 is a schematic diagram of the composition of a power system load frequency control system provided by a specific embodiment of the present invention;

4 is a comparison diagram of the frequency difference between a terminal full-order sliding mode control method and a traditional sliding mode control method in a specific embodiment of the present invention;

5 is a comparison diagram of the power difference of the tie line using the terminal full-order sliding mode control method and the traditional sliding mode control method in a specific embodiment of the present invention;

FIG. 6 is a comparison diagram of regional control difference using a terminal full-order sliding mode control method and a traditional sliding mode sliding mode control method in a specific embodiment of the present invention;

7 is a comparison diagram of the frequency difference using a linear full-order sliding mode control method and a traditional sliding mode control method in a specific embodiment of the present invention;

8 is a comparison diagram of a power difference of a tie line using a linear full-order sliding mode control method and a traditional sliding mode control method in a specific embodiment of the present invention;

9 is a comparison diagram of the regional control difference using a linear full-order sliding mode control method and a traditional sliding mode control method in a specific embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a computer device provided by another specific embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Please refer to FIG. 1 . FIG. 1 is a method for controlling load frequency of a power system provided by a specific embodiment of the present invention.

In a specific implementation manner of the present invention, an embodiment of the present invention provides a method for controlling load frequency of a power system, including:

S11: Obtain the power error and frequency deviation of the power network;

S12: Using the power error and the frequency deviation, a full-order sliding mode control method is used to calculate and obtain a control amount;

S13: Use the control variable to control the governor of the power station to adjust the load and frequency of the power network.

In the embodiment of the present invention, the power error and rate deviation of the power network need to be obtained first, and the frequency deviation refers to the difference between the actual value and the nominal value of the system frequency under normal operating conditions of the power system. The rate deviation expression is: frequency deviation = actual frequency - nominal frequency (the nominal frequency of the system in my country is 50HZ, and there are 60HZ in foreign countries); the allowable value of the normal frequency deviation of my country's power system is ±0.2HZ, when the system capacity is small, The frequency deviation value can be relaxed to ±0.5HZ; the unbalance of system active power is the root cause of frequency deviation.

所示，而终端滑模面的方程为

线性滑模面的方程为

因此，本发明使用采用全阶滑模面方程的全阶滑模控制方法，对采集到的功率误差和频率偏差进行计算，得到调节发电站的调速器的控制量，从而能够对电力网络的负荷平衡和频率稳定进行调节。Therefore, the power error and frequency deviation are closely linked and can be adjusted by the governor of the power station. In sliding mode control, the general traditional sliding mode surface is as

, while the equation for the terminal sliding surface is

The equation for the linear sliding surface is

Therefore, the present invention uses the full-order sliding mode control method using the full-order sliding mode surface equation to calculate the collected power error and frequency deviation, and obtains the control amount for adjusting the governor of the power station, so that the power network can be adjusted. Load balance and frequency stability are adjusted.

Further, in a specific implementation manner, the full-order sliding mode control method may be a full-order terminal sliding mode control method; the nonlinear equation of the full-order terminal sliding mode control method is:

Wherein, the x is a vector, the f(x, t) and the a(x, t) are both nonlinear equations, the d is an external disturbance, and the u is a control variable;

And the equation of the terminal sliding surface is:

Both β _i and λ _i in the above formula are constants; the selection of β _i makes the solutions of the polynomial p ⁿ +β _n p ^n-1 +β _n-1 p ^n-2 +…β ₂ p+β ₁ all negative ;

The selection of the λ _i refers to the following formula:

Among them, λ _n+1 =1, λ _n =λ, λ∈(0,1);

Let the equation of the terminal sliding surface be equal to zero, the control quantity is obtained:

u=a ^-1 (u _eq +u _n )=u' _eq +u' _n

in,

The u _n is:

Wherein, the v is:

Among them, l is a positive preset coefficient, s is a sliding mode surface equation, and ξ is a preset positive number.

Of course, a full-order linear sliding mode control method can also be used, that is, the full-order sliding mode control method is a full-order linear sliding mode control method; the nonlinear equation of the full-order linear sliding mode control method is:

Wherein, the x is a vector, the f(x, t) and the a(x, t) are both nonlinear equations, the d is an external disturbance, and the u is a control variable;

The equation for the linear sliding surface is:

Both β _i and λ _i in the above formula are constants; the selection of β _i makes the solutions of the polynomial p ⁿ +β _n p ^n-1 +β _n-1 p ^n-2 +…β ₂ p+β ₁ all negative ;

The selection of the λ _i refers to the following formula:

in,

λ _n+1 =1, λ _n =λ, λ∈(0,1);

Set the sliding surface equal to zero to get the control quantity:

u=a ^-1 (u _eq +u _n )=u' _eq +u' _n

in,

u _eq =-f(x,t)-β _n x _n -…-β ₁ x ₁

The u _n is:

Wherein, the v is:

Among them, l is a positive preset coefficient, s is a sliding mode surface equation, and ξ is a preset positive number. Generally, ξ is taken as a number close to zero, which can be set to 0.1, 0.01, 0.001 or a smaller number according to actual needs.

It is worth noting that when the full-order sliding mode calculation method in the above-mentioned embodiment is used to calculate the control two of the governor, it is possible to calculate the control amount that exceeds the adjustment range of the generator. , the control quantity is limited by two nonlinearities of the generator's GDB and/or GRC. That is, if the calculated control amount exceeds the maximum regulation threshold of the generator, the control amount may be controlled to be equal to the maximum regulation threshold. The maximum regulation threshold of the generator is limited by the generator's GDB (generator control deadband) and/or GRC (generator rate of change nonlinearity) nonlinearity.

The present invention provides a load frequency control method for a power system, comprising: acquiring power error and frequency deviation of a power network; using the power error and the frequency deviation to obtain a control amount by using a full-order sliding mode control method; The control variable controls the governor of the power station to regulate the load, frequency of the power network. The present invention uses the full-order sliding mode control method to control the governor. Compared with the reduced-order sliding mode control method in the prior art, the sliding mode surface method is full-order. In the frequency load regulation of the power system, Reduce singularity and reduce chattering.

Please refer to FIG. 2 . FIG. 2 is a schematic diagram of the composition of a power system load frequency control device according to another specific embodiment of the present invention.

In a second aspect, the present invention provides a power system load frequency control device 200, including:

The deviation obtaining module 210 is used to obtain the power error and frequency deviation of the power network;

a control quantity calculation module 220, configured to use the power error and the frequency deviation to calculate and obtain the control quantity by adopting a full-order sliding mode control method;

The governor control module 230 is used to control the governor of the power station by using the control quantity, so as to adjust the load and frequency of the power network.

Please refer to FIG. 3 , which is a schematic diagram of the composition of a power system load frequency control system according to an embodiment of the present invention.

In a third aspect, the present invention provides a power system load frequency control system, which is applied to a power network in which two regions are interconnected, the power network comprising: a first power network 311 and a second power network 321 connected by a tie line;

The first regional power grid is provided with a first load frequency control device 312, and the second regional power grid is provided with a second load frequency control device 322;

The first load frequency control device 312 includes:

a first deviation obtaining module, configured to obtain the first power error and the first frequency deviation of the first power network 311;

a first control quantity calculation module, configured to use the first power error, the first frequency deviation, and the second frequency deviation to calculate the first control quantity by adopting the first full-order sliding mode control method;

a first governor control module, configured to use the first control variable to control the governor 313 of the first power station to adjust the load and frequency of the first power network;

The second load frequency control device 322 includes:

a second deviation obtaining module, configured to obtain the second power error and the second frequency deviation of the second power network;

a second control variable calculation module, configured to use the second power error, the second frequency deviation, and the first frequency deviation to calculate the second control variable by using the second full-order sliding mode control method;

a second governor control module, configured to use the second control variable to control the governor of the second power station to adjust the load and frequency of the second power network 321;

In the specific implementation, please refer to Figure 3, the outputs of ACE1 and ACE2 are respectively the control variable u ₁ or u ₂ , where T _G1 and T _G2 are the time constants of the governor, T _t1 and T _t2 are the time constants of the steam box, and k _R is the high voltage rating, T _RH is the high voltage to low voltage stage time, K _p1 , K _p2 are the generator constants, T _p1 , T _p2 are the generator time constants, T ₁₂ , T ₂₁ are the tie line coefficients, ACE ₁ , ACE ₂ is the regional control error, B ₁ , B ₂ are the frequency response coefficients, R ₁ , R ₂ are the speed droop coefficients, ΔP _tie1 , ΔP _tie2 are the tie line power errors, Δf ₁ , Δf ₂ are the frequency deviations, ΔP _L1 , ΔP _L2 is the load disturbance, Δx _g1 , Δx _g2 are the valve position changes, ΔP _g1 , ΔP _g2 represent the mechanical energy (where i=1, 2 represent different regions), where the symbol 1 represents the upper half of the region in Figure 3, Reference numeral 2 represents the lower half area in FIG. 3 .

The load frequency control in Figure 3 includes two interconnected areas, each of which consists of a regulator, a steam turbine and a generator. Steam turbines include the same type: non-reheat steam turbines, and this system takes into account the governor deadband and the nonlinear constraints of the generator rate of change.

Specifically, when calculating the control variable, set Δx=Δf, and then finally obtain the third-order derivative of the frequency difference according to the transfer function of the power system. Design the sliding mode surface of the linear sliding mode control, and then bring the obtained frequency difference or its several order derivatives into the sliding mode surface of the linear sliding mode control, and finally the control amount can be obtained. Specifically, reference may be made to the setting manners in the foregoing specific implementation manner.

On the basis of the above-mentioned specific embodiment, in a specific embodiment, the third-order derivative of the frequency difference is:

where i=1 or 2.

The sliding surface can be designed as:

u _eq can be designed as:

u _n can be designed as:

The total control quantity can be designed as:

u=a ^-1 (u _eq +u _n ), as for the meaning of the parameters in this embodiment and the settings of other parts, reference may be made to the relevant content in the above-mentioned specific implementation manner.

In specific implementation, in order to achieve the adjustment consistency of the two regions and reduce the possible asynchronous conflict between different adjustment methods, the full-order sliding mode control method of the power network in the two regions can be set to the same control method. , that is to say, both the first full-order sliding mode control method and the second full-order sliding mode control method can be set as full-order terminal sliding mode control methods; , the second full-order sliding mode control method are set as full-order linear sliding mode control method.

Please refer to FIG. 4 to FIG. 9. FIG. 4 is a comparison diagram of the frequency difference between the terminal full-order sliding mode control method and the traditional sliding mode control method in a specific embodiment of the present invention; FIG. 5 is a specific embodiment of the present invention. The comparison diagram of the power difference of the tie line using the terminal full-order sliding mode control method and the traditional sliding mode control method; FIG. 6 is a specific embodiment of the present invention using the terminal full-order sliding mode control method and the traditional sliding mode sliding mode control method. The comparison diagram of the regional control difference of the present invention; FIG. 7 is the comparison diagram of the frequency difference using the linear full-order sliding mode control method and the traditional sliding mode control method in a specific embodiment of the present invention; FIG. 8 is a specific embodiment of the present invention. The comparison diagram of the power difference of the tie line using the linear full-order sliding mode control method and the traditional sliding mode control method in FIG. Contrast plot of poor zone control.

It can be seen from Fig. 4-Fig. 9 that the full-order sliding mode control method can achieve the control effect well. And compared with the traditional sliding mode control, the response time, overshoot and chattering are significantly reduced.

Please refer to FIG. 10. FIG. 10 is a schematic structural diagram of a computer device provided by another specific embodiment of the present invention.

In another specific implementation manner of the present invention, an embodiment of the present invention provides a computer device, including:

memory for storing computer programs;

The processor is configured to implement the steps of the power system load frequency control method according to any one of the above specific embodiments when executing the computer program.

Referring next to FIG. 10 , it shows a schematic structural diagram of a computer device suitable for implementing the embodiments of the present application. The computer device shown in FIG. 10 is only an example, and should not impose any limitations on the functions and scope of use of the embodiments of the present application.

As shown in FIG. 10, a computer system 1000 includes a processor (CPU) 1001, which can be executed according to a program stored in a read only memory (ROM) 1002 or a program loaded from a storage section 1008 into a random access memory (RAM) 1003 Various appropriate actions and processes are performed. In the RAM 1003, various programs and data necessary for the operation of the system 1000 are also stored.

The CPU 1001 , the ROM 1002 , and the RAM 1003 are connected to each other through a bus 1004 . An input/output (I/O) interface 1003 is also connected to the bus 1004 .

The following components are connected to the I/O interface 1005: an input section 1006 including a keyboard, a mouse, etc.; an output section 1007 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section 1008 including a hard disk, etc. ; and a communication section 1009 including a network interface card such as a LAN card, a modem, and the like. The communication section 1009 performs communication processing via a network such as the Internet. A drive 1010 is also connected to the I/O interface 1007 as needed. A removable medium 1011, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is mounted on the drive 1010 as needed so that a computer program read therefrom is installed into the storage section 1008 as needed.

In particular, according to embodiments of the present disclosure, the processes described above with reference to the flowcharts may be implemented as computer software programs. For example, embodiments of the present disclosure include a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for performing the method illustrated in the flowchart. In such an embodiment, the computer program may be downloaded and installed from the network via the communication portion 1009, and/or installed from the removable medium 1011. When the computer program is executed by the processor (CPU) 1001, the above-described functions defined in the method of the present application are performed. It should be noted that the computer-readable medium described in this application may be a computer-readable signal medium or a computer-readable medium, or any combination of the above two. The computer readable medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus or device, or a combination of any of the above. More specific examples of computer readable media may include, but are not limited to, electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read only memory (ROM), erasable programmable Read only memory (EPROM or flash memory), fiber optics, portable compact disk read only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above. In this application, a computer-readable medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, however, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code therein. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the foregoing. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable medium that can transmit, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. Program code embodied on a computer readable medium may be transmitted using any suitable medium including, but not limited to, wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

Computer program code for performing the operations of the present application may be written in one or more programming languages, including object-oriented programming languages—such as Java, Smalltalk, C++, but also conventional Procedural programming language - such as "C" language or similar programming language. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer, or entirely on the remote computer or server.

In the case of a remote computer, the remote computer may be connected to the user's computer through any kind of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (eg, using an Internet service provider through Internet connection).

The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code that contains one or more logical functions for implementing the specified functions executable instructions. It should also be noted that, in some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It is also noted that each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented in dedicated hardware-based systems that perform the specified functions or operations , or can be implemented in a combination of dedicated hardware and computer instructions.

As another specific implementation manner of the present invention, an embodiment of the present invention provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, any of the foregoing specific implementation manners are implemented. Steps of a method for controlling load frequency in a power system.

The computer-readable medium may be included in the computer or the terminal device described in the above embodiments; it may also exist alone without being assembled into the computer device. The above-mentioned computer-readable medium carries one or more programs, and when the above-mentioned one or more programs are executed by the computer equipment, the computer equipment: acquires the power error and frequency deviation of the power network; uses the power error, the The frequency deviation is calculated by using the full-order sliding mode control method to obtain the control amount; the control amount is used to control the governor of the power station to adjust the load and frequency of the power network. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory, ROM), random access memory (Random Access Memory, RAM), magnetic disk or optical disk and other media that can store program codes .

Finally, it should also be noted that in this document, relational terms such as first and second are used only to distinguish one entity or operation from another, and do not necessarily require or imply these entities or that there is any such actual relationship or sequence between operations. Moreover, the terms "comprising", "comprising" or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device that includes a list of elements includes not only those elements, but also includes not explicitly listed or other elements inherent to such a process, method, article or apparatus. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in a process, method, article or apparatus that includes the element.

A method for controlling load frequency of a power system and related products provided by the present invention have been described above in detail. The principles and implementations of the present invention are described with specific examples in this paper. The descriptions of the above embodiments are only used to help understanding The method of the present invention and its core idea; at the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be It is construed as a limitation of the present invention.

Claims (6)

1. a power system load frequency control method, is characterized in that, comprises: Obtain the power error and frequency deviation of the power network; Using the power error and the frequency deviation, the full-order sliding mode control method is used to calculate the control amount; Using the control variable to control the governor of the power station to adjust the load and frequency of the power network; The full-order sliding mode control method is a full-order linear sliding mode control method; The nonlinear equation of the full-order linear sliding mode control method is:

Among them, the

is the vector, the

and the stated

are nonlinear equations, the

for external disturbances, the

for the control amount; The equation for the linear sliding surface is:

; in the above formula

and

are constants;

The choice of makes the polynomial

The solutions are all negative; said

The selection refers to the following formula:

in,

,

,

; Set the sliding surface equal to zero to get the control quantity:

in,

said

for:

Among them, the

for:

, in,

is a positive preset coefficient,

is the sliding surface equation,

is the default positive number; When the power system load frequency control method is applied to a power network in which two regions are interconnected, the power network includes: a first regional power grid and a second regional power grid connected by a tie line; the first regional power grid is provided with a first load a frequency control device, the second regional power grid is provided with a second load frequency control device; When calculating the control amount, set

; According to the transfer function of the power system, the third derivative of the frequency difference is finally obtained; the sliding mode surface of the linear sliding mode control is designed; the obtained frequency difference or its derivatives are brought into the sliding mode surface of the linear sliding mode control, The control quantity is obtained; among them, the third derivative of the frequency difference is:

in

=1 or 2; The sliding surface is designed as:

Designed to:

Designed to:

The total control quantity is designed as:

; in

,

The outputs are the control quantities

or

,in

,

is the governor time constant,

,

is the steam box time constant,

is the high voltage rating,

is the high pressure to low pressure stage time,

,

is the generator constant,

,

is the generator time constant,

,

is the contact line coefficient,

,

is the regional control error,

,

is the frequency response coefficient,

,

is the speed droop coefficient,

,

is the tie line power error,

,

is the frequency deviation,

,

is the load disturbance,

,

is the valve position change,

,

represents mechanical energy,

is the first load frequency control device,

is the second load frequency control device, wherein,

represent different regions. 2 . The power system load frequency control method according to claim 1 , wherein the control amount is limited by the generator control dead zone of the generator and/or the non-linearity of the generator change rate. 3 . 3. A power system load frequency control device, characterized in that, comprising: The deviation acquisition module is used to obtain the power error and frequency deviation of the power network; a control quantity calculation module, configured to use the power error and the frequency deviation to calculate the control quantity by adopting a full-order sliding mode control method; a governor control module, used to control the governor of the power station by using the control quantity to adjust the load and frequency of the power network; The full-order sliding mode control method is a full-order linear sliding mode control method; The nonlinear equation of the full-order linear sliding mode control method is:

Among them, the

is the vector, the

and the stated

are nonlinear equations, the

for external disturbances, the

for the control amount; The equation for the linear sliding surface is:

; in the above formula

and

are constants;

The choice of makes the polynomial

The solutions are all negative; said

The selection refers to the following formula:

in,

,

,

; Set the sliding surface equal to zero to get the control quantity:

in,

said

for:

Among them, the

for:

, in,

is a positive preset coefficient,

is the sliding surface equation,

is the default positive number; When the power system load frequency control method is applied to a power network in which two regions are interconnected, the power network includes: a first regional power grid and a second regional power grid connected by a tie line; the first regional power grid is provided with a first load a frequency control device, the second regional power grid is provided with a second load frequency control device; When calculating the control amount, set

; According to the transfer function of the power system, the third derivative of the frequency difference is finally obtained; the sliding mode surface of the linear sliding mode control is designed; the obtained frequency difference or its derivatives are brought into the sliding mode surface of the linear sliding mode control, The control quantity is obtained; among them, the third derivative of the frequency difference is:

in

=1 or 2; The sliding surface is designed as:

Designed to:

Designed to:

The total control quantity is designed as:

; in

,

The outputs are the control quantities

or

,in

,

is the governor time constant,

,

is the steam box time constant,

is the high voltage rating,

is the high pressure to low pressure stage time,

,

is the generator constant,

,

is the generator time constant,

,

is the contact line coefficient,

,

is the regional control error,

,

is the frequency response coefficient,

,

is the speed droop coefficient,

,

is the tie line power error,

,

is the frequency deviation,

,

is the load disturbance,

,

is the valve position change,

,

represents mechanical energy,

is the first load frequency control device,

is the second load frequency control device, wherein,

represent different regions. 4. A power system load frequency control system, characterized in that it is applied to a power network in which two regions are interconnected, the power network comprising: a first regional power grid and a second regional power grid connected by a tie line; The first regional power grid is provided with a first load frequency control device, and the second regional power grid is provided with a second load frequency control device; The first load frequency control device includes: a first deviation obtaining module, configured to obtain a first power error and a first frequency deviation of the first regional power grid; a first control quantity calculation module, configured to use the first power error, the first frequency deviation, and the second frequency deviation to calculate the first control quantity by adopting the first full-order sliding mode control method; a first governor control module, configured to use the first control variable to control the governor of the first power station to adjust the load and frequency of the first regional power grid; The second load frequency control device includes: A second deviation obtaining module, configured to obtain a second power error and a second frequency deviation of the second regional power grid; a second control variable calculation module, configured to use the second power error, the second frequency deviation, and the first frequency deviation to calculate the second control variable by using the second full-order sliding mode control method; a second governor control module, configured to use the second control variable to control the governor of the second power station to adjust the load and frequency of the second regional power grid; The first full-order sliding mode control method and the second full-order sliding mode control method are both full-order linear sliding mode control methods; The nonlinear equation of the full-order linear sliding mode control method is:

Among them, the

is the vector, the

and the stated

are nonlinear equations, the

for external disturbances, the

for the control amount; The equation for the linear sliding surface is:

; in the above formula

and

are constants;

The choice of makes the polynomial

The solutions are all negative; said

The selection refers to the following formula:

in,

,

,

; Set the sliding surface equal to zero to get the control quantity:

in,

said

for:

Among them, the

for:

, in,

is a positive preset coefficient,

is the sliding surface equation,

is the default positive number; When calculating the control amount, set

; According to the transfer function of the power system, the third derivative of the frequency difference is finally obtained; the sliding mode surface of the linear sliding mode control is designed; the obtained frequency difference or its derivatives are brought into the sliding mode surface of the linear sliding mode control, The control quantity is obtained; among them, the third derivative of the frequency difference is:

in

=1 or 2; The sliding surface is designed as:

Designed to:

Designed to:

The total control quantity is designed as:

; in

,

The outputs are the control quantities

or

,in

,

is the governor time constant,

,

is the steam box time constant,

is the high voltage rating,

is the high pressure to low pressure stage time,

,

is the generator constant,

,

is the generator time constant,

,

is the contact line coefficient,

,

is the regional control error,

,

is the frequency response coefficient,

,

is the speed droop coefficient,

,

is the tie line power error,

,

is the frequency deviation,

,

is the load disturbance,

,

is the valve position change,

,

represents mechanical energy,

is the first load frequency control device,

is the second load frequency control device, wherein,

represent different regions. 5. A computer equipment, characterized in that, comprising: memory for storing computer programs; The processor is configured to implement the steps of the power system load frequency control method according to any one of claims 1 to 2 when executing the computer program. 6. A computer-readable storage medium, wherein a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the power system according to any one of claims 1 to 2 is implemented The steps of the load frequency control method.

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