CN108448582B - Harmonic detection system and harmonic processing system - Google Patents
Harmonic detection system and harmonic processing system Download PDFInfo
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- H—ELECTRICITY
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
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Abstract
The invention provides a harmonic detection system and a harmonic processing system, which relate to the technical field of new energy power generation and comprise a wind speed analysis module and a new energy machine component analysis module; the wind speed analysis module is used for analyzing the acquired wind speed data to obtain the wind speed and the wind speed type, and extracting first harmonic law information and second harmonic law information from the first packaging module and the second packaging module according to the wind speed and the wind speed type respectively; the new energy unit analysis module is used for analyzing the new energy unit information to obtain unit types, proportions and capacities, and third harmonic rule information is extracted from the third packaging module according to the unit types, proportions and capacities, so that harmonic characteristics in the system can be obtained in advance on the basis of the known wind speed condition in a future period of time or the new energy grid-connected unit information.
Description
Technical Field
The invention relates to the technical field of new energy power generation, in particular to a harmonic detection system and a harmonic processing system.
Background
Wind energy is used as inexhaustible clean pollution-free renewable energy, so that the installed capacity of the fan in China is rapidly increased. Meanwhile, the installed capacity of the wind power plant is larger and larger, the influence on the system is more and more obvious, and then the serious problem of the power quality of the wind power plant is brought to a power grid.
The harmonic detection method of the wind power system at the present stage is generally suitable for detecting the harmonic in the operation of the wind power plant. And then, performing corresponding harmonic compensation by adopting an active power filter or a hybrid power filter. The existing harmonic wave processing in the wind power system is to respectively detect the harmonic wave of the wind power plant under different operating conditions on the basis of the built wind power plant, and then compensate in real time. Therefore, corresponding compensation can not be carried out at the design stage that the wind power plant is connected into the power grid, the later-stage input equipment transformation and detection compensation engineering can bring the conditions of time consumption, labor consumption, financial consumption and the like, but the operation efficiency is low, a large amount of economic loss can be brought, and the development of the wind power industry is limited to a certain extent.
Disclosure of Invention
In view of the above, the present invention provides a harmonic detection system and a harmonic processing system, which can effectively predict wind farm harmonics at a wind farm design stage or under a known wind speed condition in a future period of time, and then adopt corresponding effective measures to make a power grid more stable.
In a first aspect, an embodiment of the present invention provides a harmonic detection system, including a wind speed analysis module and a new energy component analysis module;
the wind speed analysis module is used for analyzing the acquired wind speed data to obtain the wind speed and the wind speed type, and extracting first harmonic law information and second harmonic law information from the first encapsulation module and the second encapsulation module according to the wind speed and the wind speed type respectively;
and the new energy unit analysis module is used for analyzing the new energy unit information to obtain the unit type, proportion and capacity, and extracting third harmonic rule information from the third packaging module according to the unit type, proportion and capacity.
With reference to the first aspect, an embodiment of the present invention provides a first possible implementation manner of the first aspect, where the wind speed sensing system is further included to sense wind speed data and send the wind speed data to the wind speed analysis module.
With reference to the first aspect, an embodiment of the present invention provides a second possible implementation manner of the first aspect, where the first encapsulation module, the second encapsulation module, and the third encapsulation module are respectively encapsulated with multiple kinds of harmonic law information generated by inputting multiple kinds of wind speed data into a simulation model.
With reference to the first aspect, an embodiment of the present invention provides a third possible implementation manner of the first aspect, where the first harmonic law information includes:
for the grid-connected double-fed wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the current harmonic distortion rate of the grid-side converter side, the current harmonic distortion rate of the stator side and the current harmonic distortion rate of the double-fed wind power generation grid-connected point all show a descending trend; when the rated wind speed is reached and the wind speed is continuously increased, the harmonic distortion rate of the current at the side of the grid-side converter, the harmonic distortion rate of the current at the side of the stator and the harmonic distortion rate of the current at the grid-connected point of the double-fed wind power generation tend to be stable.
With reference to the first aspect, an embodiment of the present invention provides a fourth possible implementation manner of the first aspect, where the first harmonic law information further includes:
for the grid-connected direct-drive wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the current harmonic distortion rate of each bus is in a descending trend; when the rated wind speed is reached and the wind speed is continuously increased, the harmonic current distortion rate of each bus is in an increasing trend.
With reference to the first aspect, an embodiment of the present invention provides a fifth possible implementation manner of the first aspect, where the second harmonic law information includes:
the more severe the wind speed change, the more the influence on the harmonic distortion rate of the wind turbine grid-connected system, wherein the wind speed types include basic wind, gust wind, slowly changing and gradually changing wind, rapidly changing and gradually changing wind and random wind.
With reference to the first aspect, an embodiment of the present invention provides a sixth possible implementation manner of the first aspect, where the third harmonic law information includes:
the harmonic characteristics of the wind power system are not influenced by the photovoltaic hybrid new energy power generation system; when the double-fed type and the direct-drive type fans are simultaneously connected to the power generation system in a grid mode, the harmonic characteristic influence of the double-fed type wind power system on the wind power system is larger than the harmonic characteristic influence of the double-fed type wind power system on the wind power system when the double-fed type and the direct-drive type fans are connected to the grid mode independently, and the harmonic characteristic influence of the direct-drive type wind power system on the wind power system is smaller than the harmonic characteristic influence of the direct-drive type wind power system on the wind power system when.
In a second aspect, an embodiment of the present invention further provides a harmonic processing system, including the harmonic detection system as described above, and further including a harmonic compensation system for acquiring harmonic law information.
With reference to the second aspect, an embodiment of the present invention provides a first possible implementation manner of the second aspect, where the harmonic compensation system is further configured to generate a harmonic compensation amount according to the harmonic law information.
With reference to the first aspect, an embodiment of the present invention provides a second possible implementation manner of the second aspect, wherein the harmonic processing system is disposed at a common connection point of the new energy power generation system and the power grid.
The invention provides a harmonic detection system and a harmonic processing system, and relates to the technical field of new energy power generation.A wind speed analysis module can analyze and judge the size change and the type change of wind speed and then call first harmonic rule information and second harmonic rule information corresponding to the size change and the type change of the wind speed; the new energy source unit analysis module analyzes the new energy grid-connected unit information, can judge the type, proportion and capacity of the new energy source unit, and then calls third harmonic law information corresponding to the unit information. The three kinds of harmonic law information can be used as a harmonic compensation system operation basis, the whole harmonic detection compensation structure is packaged into a harmonic processing system and is connected to a public connection point of a wind power plant and a power grid, so that the harmonic characteristics in the system can be obtained in advance on the basis of the known wind speed condition or new energy grid-connected unit information in a future period of time, the harmonic detection compensation after the wind power plant is in grid-connected operation is avoided, the time is saved, the high operation efficiency is achieved, meanwhile, excessive harmonic pollution is avoided to a certain extent, the grid-connected electric energy quality is improved, the installation of excessive harmonic detection devices is avoided, and the high economical efficiency is achieved.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, preferred embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
FIG. 1 is a functional block diagram of a harmonic detection system according to an embodiment of the present invention;
FIG. 2 is a diagram illustrating the basic wind effect of a superimposed random wind according to an embodiment of the present invention;
fig. 3 is a gust effect diagram of a superimposed random wind according to an embodiment of the present invention;
FIG. 4 is a diagram illustrating the effect of a gradual change of a superimposed random wind according to an embodiment of the present invention;
fig. 5 is a functional block diagram of a harmonic processing system according to an embodiment of the present invention.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is apparent that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
At present, harmonic detection methods of wind power systems at present mainly include a harmonic detection method based on fourier transform, a harmonic detection method based on an instantaneous reactive power theory, a harmonic detection method based on a neural network, a harmonic detection method based on an adaptive cancellation principle, and a harmonic detection method based on wavelet analysis, and these methods are generally suitable for detecting harmonics in the operation of a wind power plant. And then, performing corresponding harmonic compensation by adopting an active power filter or a hybrid power filter.
The existing harmonic wave processing in the wind power system is to respectively detect the harmonic wave of the wind power plant under different operating conditions on the basis of the built wind power plant, and then compensate in real time. Therefore, corresponding compensation can not be carried out at the design stage that the wind power plant is connected into the power grid, the later-stage input equipment transformation and detection compensation engineering can bring the conditions of time consumption, labor consumption, financial consumption and the like, but the operation efficiency is low, a large amount of economic loss can be brought, and the development of the wind power industry is limited to a certain extent.
Based on the harmonic detection system and the harmonic processing system provided by the embodiment of the invention, the harmonic of the wind power plant can be effectively predicted at the design stage of the wind power plant or under the condition of the wind speed in a known future period of time, and then the power grid can be more stable by taking corresponding effective measures.
In order to facilitate understanding of the embodiment, a harmonic detection system disclosed in the embodiment of the present invention is first described in detail;
fig. 1 is a functional block diagram of a harmonic detection system according to an embodiment of the present invention.
Referring to fig. 1, the harmonic detection system includes a wind speed analysis module and a new energy component analysis module;
the wind speed analysis module is used for analyzing the acquired wind speed data to obtain the wind speed and the wind speed type, and extracting first harmonic law information and second harmonic law information from the first packaging module and the second packaging module according to the wind speed and the wind speed type respectively;
and the new energy unit analysis module is used for analyzing the new energy unit information to obtain the unit type, the proportion and the capacity, and extracting third harmonic rule information from the third packaging module according to the unit type, the proportion and the capacity.
Specifically, the embodiment of the invention is based on harmonic wave influence factors of a wind power system, experimental summary and induction are carried out on influence rules of wind speed, wind conditions (wind speed types), a new energy unit and the like on system harmonic waves, and the influence rules are independently packaged in a small module.
Furthermore, the wind speed sensing system is used for sensing wind speed data and sending the wind speed data to the wind speed analysis module.
Specifically, the wind speed sensing system can sense the change of wind speed and transmit wind speed data to the wind speed analysis module, the wind speed analysis module can analyze and judge the change of the wind speed and the change of the type of the wind speed, and then first harmonic law information and second harmonic law information corresponding to the change of the wind speed and the change of the type of the wind speed are called;
furthermore, the first packaging module, the second packaging module and the third packaging module are respectively packaged with various harmonic law information generated by inputting various wind speed data into the simulation model.
The first harmonic law information, the second harmonic law information and the third harmonic law information are respectively packaged in separate packaging modules, and then the first packaging module, the second packaging module and the third packaging module are embedded into the harmonic detection system, so that the corresponding harmonic law information in the packaging modules can be called at any time according to the condition of the wind power system and can be used as the basis for the operation of the harmonic compensation system.
In the actual project, because the harmonic distribution condition of the wind power system can not be predicted, the compensation measures can not be taken in advance, the conditions of time consumption, labor consumption, financial consumption and the like are brought by equipment transformation and detection compensation projects in the later period, the operation efficiency is low, the economic loss is serious, and the quality of the electric energy transmitted to a power grid by the wind power plant can not be guaranteed. The method has good economy;
the method comprises the following steps of taking wind speed data of various conditions as input of a simulation model to obtain harmonic law information of various conditions;
further, the first harmonic law information includes:
for the grid-connected double-fed wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the current harmonic distortion rate of the grid-side converter side, the current harmonic distortion rate of the stator side and the current harmonic distortion rate of the double-fed wind power generation grid-connected point all show a descending trend; when the rated wind speed is reached and the wind speed is continuously increased, the harmonic distortion rate of the current at the side of the grid-side converter, the harmonic distortion rate of the current at the side of the stator and the harmonic distortion rate of the current at the grid-connected point of the double-fed wind power generation tend to be stable.
Further, the first harmonic law information further includes:
for the grid-connected direct-drive wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the current harmonic distortion rate of each bus is in a descending trend; when the rated wind speed is reached and the wind speed is continuously increased, the harmonic current distortion rate of each bus is in an increasing trend.
First harmonic law information of wind speed to harmonic waves of a double-fed and direct-drive wind power system is obtained through simulation experiments, wherein for internal harmonic characteristics of the grid-connected double-fed wind power system, the harmonic waves are mainly concentrated in 6k +/-1 (k is 1,2 and 3.) times, low-order harmonic waves occupy the main part, the higher the harmonic frequency is, the lower the amplitude is, and the harmonic amplitudes near the switching frequency and the integral multiple frequency are relatively large.
For a grid-connected Double-fed wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the current THD (Total harmonic Distortion) at the side of a grid-side converter is large and shows a remarkable descending trend, and the harmonic Distortion of the current at the grid-connected point of a stator side and a DFIG (Double-fed-asynchronous wind power Generator) is small and slightly reduced;
when the rated wind speed is reached and the wind speed is continuously increased, the current harmonic distortion rates of the grid-side converter side, the stator side and the doubly-fed wind power generation grid-connected point tend to be stable, the harmonic current distortion rates of the stator side and the doubly-fed wind power generation grid-connected point current harmonic distortion rates are extremely small, and the current distortion rate of the grid-side converter side is maintained to be near 5%;
for the grid-connected direct-drive wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the harmonic distortion rate of each bus current is gradually reduced, the wind speed is continuously increased after the rated wind speed is reached, and the harmonic current distortion rate of each bus is slightly increased.
Further, the second harmonic law information includes:
the more severe the wind speed type changes, the more the influence on the harmonic distortion rate of the wind turbine grid-connected system is, wherein the wind speed type comprises basic wind, gust wind, slowly and gradually changing wind, rapidly and gradually changing wind and random wind.
The second harmonic law information of the influence of wind conditions on the harmonic waves of the wind power generation system is obtained through a simulation experiment, and wind based on the nature has the characteristics of randomness, intermittence, uncertainty and the like, and the change characteristic of the wind speed is described by a four-component model in theoretical research, namely the wind speed is decomposed into: basic wind, gust wind, gradual wind and random wind. The wind in the nature can be generally expressed by four typical wind speeds, namely basic wind accompanying random wind, slowly-changing gradual wind (the wind speed can reach v at time T, which is conveniently called as 'type I gradual wind' in a table), rapidly-changing gradual wind (the wind speed can reach v at time T, T is less than T, which is conveniently called as 'type II gradual wind' in a table), gust and the like.
The rule of influence of wind conditions on harmonic characteristics of the grid-connected direct-drive wind power system is that gust and II-type gradual change wind have large influence. The current distortion condition of the grid-side converter is mainly influenced by class II gradient wind, the current harmonic distortion rate at the access point of the wind power plant and the power grid is the maximum when the input wind condition is gust, the class II gradient wind frequency, the class I gradient wind and the basic wind accompanying random wind are smaller, and the more severe the wind speed change is, the larger the influence on the harmonic distortion rate of a wind turbine grid-connected system is.
Here, the fluctuation of the wind speed can cause disturbance of the grid-connected power quality of the wind power generation system, and a corresponding wind speed model needs to be established for researching the harmonic characteristics of the grid-connected wind power generation system, so that correct source parameters are provided for the simulation research of the subject. Wind has randomness and volatility, and in order to describe the varying characteristics of wind speed in theoretical studies, it is now common to base a four-component model, i.e. the wind speed V is decomposed into: the basic wind, gust, gradual wind and random wind are defined as follows:
V(t)＝Vb+Vg(t)+Vr(t)+Vn(t) (1)
wherein, V in the formula (1)b-basic wind speed (m/s);
Vg-wind gust speed (m/s);
Vr-gradual wind speed (m/s);
Vn-random wind speed (m/s).
The embodiment of the invention is based on an MATLAB/Simulink platform, a four-component model is utilized to model a plurality of practical typical wind speed types, a foundation is laid for the follow-up study of the influence of the wind speed types on the harmonic characteristics of a grid-connected wind power generation system, and the simulation results of various wind speed types are shown in FIGS. 2-4;
here, fig. 2 shows the basic wind effect of the superimposed random wind, which is present in the whole normal operation process of the wind farm and does not change with time, and determines the rated power output by the wind power system. The wind speed data is obtained by calculation through a maximum likelihood estimation algorithm according to wind speed data detected in a wind power plant for a long time, and a formula (2) is as follows:
wherein C and K are parameters of the Weibull distribution. In theoretical studies, it is generally assumed that the fundamental wind is constant, taking a constant;
fig. 3 is a gust effect of superimposed random wind, the gust is used to describe a process of a sudden change of wind speed, and a turbulent airflow generates an instantaneous peak wind speed, which is easy to cause a dynamic change of an electrical quantity of a grid-connected wind power system, and the characteristic is generally described by a cosine function. Equation (3) is as follows:
t in formula (3)g1-gust start time(s);
Vgmax-peak value of gust wind speed (m/s);
Tg-gust periods(s).
Here, fig. 4 is a diagram of the effect of a gradual wind by superimposing random winds, which is used to describe the gradual change (rising or falling) characteristic of the wind speed. Equation (4) is as follows:
v in formula (4)rmax-maximum value of the gradient wind speed (m/s);
tr1-a gradual wind start time(s);
tr2-gradual wind end time(s), where tr2>tr1。
Here, random wind is used to describe the characteristic of continuous and irregular variation of wind speed, and the fluctuation of such wind speed is usually represented by a random noise wind component superimposed on the average wind speed. Equation (5) is as follows:
v in formula (5)n_max-the amplitude of the random component;
Ramrandom numbers between (-1,1) -1 and 1, subject to uniform distribution;
wvthe average interval of wind speed fluctuation is generally 0.5 pi to 2 pi (rad/s);
Further, the third harmonic law information includes:
the harmonic characteristics of the wind power system are not influenced by the photovoltaic hybrid new energy power generation system; when the double-fed type and the direct-drive type fans are simultaneously connected to the grid in the power generation system, the harmonic characteristic of the wind power system is influenced more greatly by the double-fed type wind power system than by independent grid connection of the double-fed type wind power system, and the harmonic characteristic of the wind power system is influenced less by the direct-drive type wind power system than by independent grid connection of the direct-drive type wind power system.
And obtaining third harmonic rule information of the new energy type to the wind power generation system harmonic through a simulation experiment.
Specifically, at the present stage, with the development of a photovoltaic grid connection technology, the utilization rate of photovoltaic is gradually improved, and the photovoltaic grid connection technology is not only limited to wind power single grid connection, but also is more and more common to wind and light hybrid grid connection. The rule of the influence of the new energy type on the harmonic characteristics of the wind power generation system is that in the hybrid new energy power generation system with photovoltaic, the photovoltaic is kept relatively independent, the harmonic characteristics of the wind power system cannot be influenced, and the harmonic content of the photovoltaic is low; in a double-fed type and direct-drive type fan simultaneous grid-connected power generation system, the harmonic of a double-fed wind power system is more distorted than that of the double-fed wind power system during independent grid connection due to the existence of the direct-drive fan, and the distortion of the direct-drive wind power system is smaller than that of the direct-drive wind power system during independent grid connection, namely, the mutual harmonic content can be influenced by the interconnection of the double-fed wind power system and the direct-drive fan; the grid-connected system and the double-fed direct-drive grid-connected system are similar in grid-connected condition.
Further, as shown in fig. 5, an embodiment of the present invention further provides a harmonic processing system, which includes the harmonic detection system as described above, and further includes a harmonic compensation system for acquiring harmonic law information.
Further, the harmonic compensation system is also used for generating harmonic compensation quantity according to the harmonic rule information.
The harmonic supplementing system adopts an active power filter, corresponding harmonic rule information is obtained by calling a harmonic detection module to detect wind speed, and then an amount opposite to the predicted generated harmonic phase is generated, so that the aim of reducing harmonic waves is fulfilled;
further, the harmonic processing system is arranged at a public connection point of the new energy power generation system and the power grid.
Here, the harmonic detection system and the harmonic compensation system are packaged in one module and are used as a harmonic processing system and connected to a common connection point of new energy grid-connected power generation.
Aiming at the defects of the conventional scheme in the aspects of solving the harmonic detection and suppression of a wind power system, the embodiment of the invention provides a method for effectively predicting the harmonic of a wind power plant at the design stage of the wind power plant or under the condition of the wind speed within a known future period of time, and then a power grid is more stable by adopting corresponding effective measures;
firstly, simulating the operation of a wind power system in a real situation by using simulation software based on harmonic influence factors in the wind power system, analyzing harmonic data through a large number of simulation experiments, seeking characteristic harmonics and change rules under specific conditions, summarizing and concluding the rules, and taking the rules as the basis of harmonic prediction evaluation of the wind power system in actual engineering under different operation conditions; the method is beneficial to achieving the purpose of pre-judging the harmonic waves of the wind power system by considering the type and the installation proportion of the fan or under the condition of the known wind speed in a future period of time in the design stage of the wind power plant;
the wind speed sensing system can sense the change of wind speed and transmit wind speed data to the wind speed analysis module, and the wind speed analysis module can analyze and judge the size change and the type change of the wind speed and then call first harmonic law information and second harmonic law information corresponding to the size change and the type change of the wind speed; and manually inputting the information of the new energy grid-connected unit to a new energy unit analysis module, judging the type, proportion and capacity of the new energy unit, and calling third harmonic law information corresponding to the information of the unit. The three kinds of harmonic law information can be used as the operating basis of a harmonic compensation system. The whole harmonic detection compensation structure is packaged into a harmonic processing system and is connected to a public connection point of a wind power plant and a power grid, so that the harmonic characteristics in the system can be obtained in advance on the basis of the known wind speed condition in a future period or new energy grid-connected unit information, the harmonic detection compensation after the wind power plant is in grid-connected operation is avoided, the time is saved, the operation efficiency is higher, excessive harmonic pollution is avoided to a certain extent, the grid-connected electric energy quality is improved, the installation of excessive harmonic detection devices is avoided, and the harmonic detection compensation method has good economy.
The harmonic processing system provided by the embodiment of the invention has the same technical characteristics as the harmonic detection system provided by the embodiment, so that the same technical problems can be solved, and the same technical effects can be achieved.
The harmonic detection system and the computer program product of the harmonic processing system provided in the embodiments of the present invention include a computer-readable storage medium storing program codes, where instructions included in the program codes may be used to execute the methods described in the foregoing method embodiments, and specific implementations may refer to the method embodiments and are not described herein again.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the system and the apparatus described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In addition, in the description of the embodiments of the present invention, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present invention may be embodied in the form of a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The embodiment of the present invention further provides an electronic device, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the processor executes the computer program, the steps of the harmonic detection and processing method provided in the foregoing embodiment are implemented.
The embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the harmonic detection and processing method of the above embodiment are performed.
Finally, it should be noted that: the above-mentioned embodiments are only specific embodiments of the present invention, which are used for illustrating the technical solutions of the present invention and not for limiting the same, and the protection scope of the present invention is not limited thereto, although the present invention is described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: any person skilled in the art can modify or easily conceive the technical solutions described in the foregoing embodiments or equivalent substitutes for some technical features within the technical scope of the present disclosure; such modifications, changes or substitutions do not depart from the spirit and scope of the embodiments of the present invention, and they should be construed as being included therein. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (7)
1. A harmonic detection system is characterized by comprising a wind speed analysis module and a new energy machine analysis module;
the wind speed analysis module is used for analyzing the acquired wind speed data to obtain the wind speed and the wind speed type, and extracting first harmonic law information and second harmonic law information from the first encapsulation module and the second encapsulation module according to the wind speed and the wind speed type respectively;
the new energy unit analysis module is used for analyzing the new energy unit information to obtain unit type, proportion and capacity, and extracting third harmonic rule information from the third packaging module according to the unit type, proportion and capacity;
the first harmonic law information includes:
for the grid-connected double-fed wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the current harmonic distortion rate of the grid-side converter side, the current harmonic distortion rate of the stator side and the current harmonic distortion rate of the double-fed wind power generation grid-connected point all show a descending trend; when the rated wind speed is reached and the wind speed is continuously increased, the harmonic distortion rate of the current at the side of the grid-side converter, the harmonic distortion rate of the current at the side of the stator and the harmonic distortion rate of the current at the grid-connected point of the double-fed wind power generation tend to be stable;
the second harmonic law information includes:
the more severe the wind speed type changes, the more the influence on the harmonic distortion rate of the wind turbine grid-connected system is, wherein the wind speed type comprises basic wind, gust wind, slowly and gradually changed wind, rapidly and gradually changed wind and random wind;
the third harmonic law information includes:
the harmonic characteristics of the wind power system are not influenced by the photovoltaic hybrid new energy power generation system; when the double-fed type and the direct-drive type fans are simultaneously connected to the power generation system in a grid mode, the harmonic characteristic influence of the double-fed type wind power system on the wind power system is larger than the harmonic characteristic influence of the double-fed type wind power system on the wind power system when the double-fed type and the direct-drive type fans are connected to the grid mode independently, and the harmonic characteristic influence of the direct-drive type wind power system on the wind power system is smaller than the harmonic characteristic influence of the direct-drive type wind power system on the wind power system when.
2. The harmonic detection system of claim 1 further comprising a wind speed sensing system for sensing wind speed data and sending the wind speed data to the wind speed analysis module.
3. The harmonic detection system according to claim 1, wherein the first encapsulation module, the second encapsulation module, and the third encapsulation module are respectively encapsulated with a plurality of kinds of harmonic law information generated by a plurality of kinds of wind speed data input simulation models.
4. The harmonic detection system of claim 1 wherein the first harmonic regularity information further comprises:
for the grid-connected direct-drive wind power system, when the wind speed is lower than the rated wind speed and continuously increases, the current harmonic distortion rate of each bus is in a descending trend; when the rated wind speed is reached and the wind speed is continuously increased, the harmonic current distortion rate of each bus is in an increasing trend.
5. A harmonic processing system comprising the harmonic detection system of any one of claims 1 to 4, further comprising a harmonic compensation system for obtaining harmonic law information.
6. The harmonic processing system of claim 5 wherein the harmonic compensation system is further configured to generate a harmonic compensation amount based on the harmonic rule information.
7. The harmonic processing system of claim 5 wherein the harmonic processing system is disposed at a point of common connection of a new energy power generation system to a power grid.
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