CN114188946A - Method and system for processing abnormal frequency of new energy station under broadband harmonic working condition - Google Patents

Method and system for processing abnormal frequency of new energy station under broadband harmonic working condition Download PDF

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Publication number
CN114188946A
CN114188946A CN202111395099.6A CN202111395099A CN114188946A CN 114188946 A CN114188946 A CN 114188946A CN 202111395099 A CN202111395099 A CN 202111395099A CN 114188946 A CN114188946 A CN 114188946A
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new energy
energy station
instantaneous voltage
time interval
frequency modulation
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樊熠
秦世耀
李少林
曲春辉
张梅
贺敬
李春彦
苗风麟
杨宁宁
刘厦
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State Grid Corp of China SGCC
China Electric Power Research Institute Co Ltd CEPRI
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State Grid Corp of China SGCC
China Electric Power Research Institute Co Ltd CEPRI
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/01—Arrangements for reducing harmonics or ripples
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/24—Arrangements for preventing or reducing oscillations of power in networks
    • H02J3/241—The oscillation concerning frequency
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J3/00—Circuit arrangements for ac mains or ac distribution networks
    • H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
    • H02J3/46—Controlling of the sharing of output between the generators, converters, or transformers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y02E10/56—Power conversion systems, e.g. maximum power point trackers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/70—Wind energy
    • Y02E10/76—Power conversion electric or electronic aspects
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
    • Y02E40/40—Arrangements for reducing harmonics

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  • Power Engineering (AREA)
  • Supply And Distribution Of Alternating Current (AREA)

Abstract

The invention provides a method and a system for processing abnormal frequency of a new energy station under a broadband harmonic working condition, wherein the method comprises the following steps: acquiring instantaneous voltages of different electrical position measurement points of the new energy station; calculating the number of zero crossings of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero crossings when the number of the zero crossings of the voltage is abnormal; and determining whether to lock the fast frequency modulation function of the new energy station based on the time interval between two adjacent zero-crossing points and a set threshold value. According to the invention, whether the fast frequency modulation function of the new energy station is locked or not is rapidly judged through whether the number of the zero crossing points in the power frequency period is abnormal or not and the time interval between the two zero crossing points, so that the misoperation of the frequency modulation device is effectively prevented, the frequency modulation action times of the new energy station are reduced, and the safety and stability of a power grid and the economy of a power generation unit/an energy storage device in the station are improved.

Description

Method and system for processing abnormal frequency of new energy station under broadband harmonic working condition
Technical Field
The invention relates to the field of new energy access and control, in particular to a new energy station abnormal frequency processing method and system under a broadband harmonic working condition.
Background
With the proposal of the important strategic goals of carbon peak reaching, carbon neutralization, a large number of wind power plants and photovoltaic power stations (hereinafter referred to as new energy plants) are merged into a power grid for a long time in the future, and new energy is gradually becoming a main power source. The new energy station power generation unit is connected to a power grid through a power electronic device, and the characteristics of low inertia, weak support, broadband harmonic and the like are further highlighted, so that the new energy station is required to actively take measures to overcome existing adverse effects, such as active participation in power system frequency adjustment, broadband harmonic suppression and the like. The wind power plant has the capability of fast frequency adjustment/response, and gives specific requirements on related inertia response and primary frequency modulation. For example, the inertia response active rise time of the wind power plant is required to be not more than 1s, the primary frequency modulation active rise time is required to be not more than 9s, and the steady state deviation is required to be not more than +/-1% Pn(PnRated power for new energy station), for new energy stationThe real-time and accuracy of the fast frequency adjustment of the station put high demands on the system. This places higher demands on the accuracy of the frequency measurement.
However, the broadband harmonic existing in the frequency measurement result affects the accuracy of the measurement result, and may cause malfunction of the existing wind farm fast frequency adjustment device (including inertia response and primary frequency modulation control), and one effective method for preventing the malfunction in the prior art is to add a band-pass filter (the band-pass filter is usually set to be 0-100 Hz) at the front end of data processing. However, the existence of harmonics within 100Hz causes a large error in the frequency calculation result. Under the condition, if a rapid frequency modulation mechanism of the new energy station is triggered due to large frequency calculation error, the grid-connected point of the new energy station will have large power fluctuation, which is not beneficial to the safety and stability of the power grid and the economic operation of the new energy station, and even may cause the off-grid of part of the power generation units of the new energy station. Therefore, under the actual conditions of high-proportion renewable energy sources and high-proportion power electronization, the main reason of power grid frequency fluctuation is quickly identified, and it is very important to obtain more accurate power grid frequency.
The defects exist at present: under the working condition of voltage waveform distortion of the power system, particularly when 0-100Hz frequency band harmonic waves (including subharmonic waves and ultralow frequency harmonic waves) exist, frequency calculation errors are increased; the existence of the broadband harmonic easily generates a frequency out-of-limit event, so that a fast frequency control strategy (primary frequency modulation and inertia response) of the new energy station malfunctions.
Disclosure of Invention
In order to solve the problem that the frequency calculation result has a large error due to the adoption of a band-pass filter in the prior art under the broadband harmonic working condition, and further the power fluctuation of a new energy station grid-connected point is large in amplitude, the invention provides a new energy station abnormal frequency processing method under the broadband harmonic working condition, which comprises the following steps of:
acquiring instantaneous voltages of different electrical position measurement points of the new energy station;
calculating the number of zero crossings of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero crossings when the number of the zero crossings of the voltage is abnormal;
and determining locking and opening of the fast frequency modulation function of the new energy station based on the time interval between two adjacent zero-crossing points and a set threshold value.
Preferably, the acquiring instantaneous voltages of different electrical position measurement points of the new energy station includes:
and acquiring instantaneous voltage of a grid-connected point of the new energy station, instantaneous voltage of a bus in the station and instantaneous voltage of an outlet side of a power generation unit.
Preferably, the determining of locking and unlocking of the new energy station fast frequency modulation function based on the time interval between two adjacent zero-crossing points, the set minimum threshold and the set maximum threshold includes:
determining whether to temporarily lock a new energy station fast frequency modulation function based on the time interval of the grid-connected point instantaneous voltage and a set minimum threshold;
when the new energy station rapid frequency modulation function is temporarily locked, determining whether the new energy station rapid frequency modulation function is continuously locked or not based on the time interval of the instantaneous voltage of the bus in the station and/or the instantaneous voltage at the outlet side of the power generation unit and the set minimum threshold;
when the rapid frequency modulation function of the new energy station is continuously locked, determining whether to start the rapid frequency modulation function of the new energy station based on the time interval of the instantaneous voltage of the grid-connected point and a set maximum threshold;
wherein the set threshold comprises a set minimum threshold and a set maximum threshold.
Preferably, the determining whether to temporarily lock the new energy station fast frequency modulation function based on the time interval of the grid-connected point instantaneous voltage and a set threshold includes:
and temporarily locking the function of quickly modulating the frequency of the new energy station when the time interval of the instantaneous voltage of the grid-connected point is continuously less than a preset threshold value for at least two times.
Preferably, when the new energy station fast frequency modulation function is temporarily locked, determining whether to continuously lock the new energy station fast frequency modulation function based on whether a time interval of a bus instantaneous voltage and/or a power generation unit outlet side instantaneous voltage in the station is smaller than the set threshold includes:
and when the time interval of the instantaneous voltage of the bus in the station and/or the instantaneous voltage at the outlet side of the power generation unit is smaller than the set threshold value, the rapid frequency modulation function of the new energy station is continuously locked.
Preferably, when the new energy station fast frequency modulation function is continuously locked, determining whether to start the new energy station fast frequency modulation function based on the time interval of the grid-connected point instantaneous voltage and a set maximum threshold value, includes:
and when the time interval of the instantaneous voltage of the grid-connected point is continuously greater than the set maximum threshold value for at least two times, starting the rapid frequency modulation function of the new energy station.
Preferably, the step of determining that the number of zero-crossing points of the voltage is abnormal includes:
and when the zero crossing point number of the instantaneous voltage of the grid-connected point, the instantaneous voltage of the bus in the station and the instantaneous voltage at the outlet side of the power generation unit is greater than the zero crossing point number corresponding to the power frequency cycle, judging that the zero crossing point number of the voltage is abnormal.
Preferably, the number of zero-crossing points corresponding to the power frequency cycle is calculated according to the following formula:
SX＝2N+1
in the formula, N is the number of power frequency cycles.
Based on the same invention concept, the invention also provides a system for processing the abnormal frequency of the new energy station under the broadband harmonic working condition, which comprises the following steps:
the acquisition module is used for acquiring instantaneous voltages of different electrical position measurement points of the new energy station;
the calculation module is used for calculating the number of the zero-crossing points of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero-crossing points when the number of the zero-crossing points of the voltage is abnormal;
and the regulating and controlling module is used for determining locking and opening of the fast frequency modulation function of the new energy station based on the time interval between the two adjacent zero crossing points and a set threshold value.
Preferably, the regulatory module comprises:
the temporary locking submodule is used for determining whether to lock the quick frequency modulation function of the new energy station temporarily or not based on the time interval of the instantaneous voltage of the grid-connected point and a set threshold;
the continuous locking sub-module is used for determining whether to continuously lock the rapid frequency modulation function of the new energy station based on the time interval of the instantaneous voltage of the bus in the station and/or the instantaneous voltage at the outlet side of the power generation unit and the set minimum threshold when the rapid frequency modulation function of the new energy station is temporarily locked;
the starting submodule is used for determining whether to start the rapid frequency modulation function of the new energy station or not based on the time interval of the instantaneous voltage of the grid-connected point and a set maximum threshold value when the rapid frequency modulation function of the new energy station is continuously locked;
wherein the set threshold comprises a set minimum threshold and a set maximum threshold.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a method for processing abnormal frequency of a new energy station under a broadband harmonic working condition, which comprises the following steps: acquiring instantaneous voltages of different electrical position measurement points of the new energy station; calculating the number of zero crossings of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero crossings when the number of the zero crossings of the voltage is abnormal; and determining locking and opening of the fast frequency modulation function of the new energy station based on the time interval between two adjacent zero-crossing points and a set threshold value. According to the invention, whether the fast frequency modulation function of the new energy station is locked or not is rapidly judged through whether the number of the zero crossing points in the power frequency period is abnormal or not and the time interval between the two zero crossing points, so that the false frequency modulation operation is effectively prevented, the frequency modulation action times of the new energy station are reduced, and the safety and stability of a power grid and the economy of a wind turbine generator/energy storage device in the station are improved.
Drawings
FIG. 1 is a flowchart of a new energy station abnormal frequency processing method under a broadband harmonic working condition according to the present invention;
FIG. 2 is a schematic diagram of different electrical position measurement points of the new energy station according to the present invention;
fig. 3 is a flowchart of a new energy station abnormal frequency identification method under a broadband harmonic working condition according to the present invention.
Detailed Description
According to the method and the system for processing the abnormal frequency of the new energy station under the broadband harmonic working condition, when the frequency result of the new energy station is abnormally changed due to broadband harmonics, the new energy station is quickly identified, and whether to lock the quick frequency response control of the new energy station and whether to put into broadband harmonic suppression measures of the new energy station or not is determined. The voltage is not subjected to filtering processing, the change trend of the real power grid frequency is identified, and the rapid frequency control strategy investment or locking of the new energy station is favorably and accurately judged; according to the processing results of voltage data of different electrical positions in a new energy station grid-connected point and a new energy station grid-connected point, synchronously judging out-of-limit dominant factors of frequency, locking or keeping fast frequency control of the new energy station according to needs, putting in a broadband harmonic suppression strategy if necessary, reducing misjudgment and misoperation, and ensuring economic operation and safe and stable operation of an electric power system of the new energy station; the method does not need to increase hardware, can run in parallel with the existing frequency calculation processing method, and has good portability.
Compared with the prior art, the method does not actively filter the collected voltage, shortens the calculation processing time, has no phase angle deviation, is beneficial to quick intervention of a frequency control strategy or prevention of maloperation, and ensures safe, stable and economic operation of the power system/new energy station.
Example 1:
a method for processing abnormal frequency of a new energy station under a broadband harmonic working condition is disclosed, as shown in FIG. 1:
s1: acquiring instantaneous voltages of different electrical position measurement points of the new energy station;
s2: calculating the number of zero crossings of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero crossings when the number of the zero crossings of the voltage is abnormal;
s3: and determining locking and opening of the fast frequency modulation function of the new energy station based on the time interval between two adjacent zero-crossing points and a set threshold value.
The invention provides a method for processing abnormal frequency of a new energy station under a broadband harmonic working condition, which comprises the following steps:
the collecting of the instantaneous voltages of the different electrical position measurement points of the new energy station in the S1 specifically includes:
different electrical position measuring points of the new energy station are shown in fig. 2 and comprise new energy station grid-connected points, 35kV/10kV buses and power generation unit (wind turbine generator/photovoltaic inverter) outlet sides.
Acquisition of new energy field station instantaneous voltage U with fixed sampling rateHInstantaneous voltage U of bus in stationMAnd the instantaneous voltage UL at the outlet side of the power generation unit (wind turbine generator/photovoltaic inverter), wherein the instantaneous voltage of the bus in the station is 35kV/10kV bus instantaneous voltage.
In S2, the power frequency is used as a period, the number of zero-crossing points of the instantaneous voltage is calculated, and when the number of zero-crossing points of the voltage is abnormal, a time interval between two adjacent zero-crossing points is calculated, which specifically includes:
calculating instantaneous voltage U by using power frequency as periodH、UMAnd ULThe number of zero crossing points is preliminarily judged whether the abnormity exists;
if the number of zero crossing points is abnormal, calculating UH、UMAnd ULTime interval T between two adjacent zero crossingsH、TMAnd TL。
In S3, determining locking and unlocking of the new energy station fast frequency modulation function based on the time interval between two adjacent zero-crossing points and the set threshold specifically includes:
judgment of THWhether it is less than the set threshold value Tx(e.g. T)xSet to 0.5ms) if T occurs at least 2 consecutive timesHIf the frequency of the new energy station is less than the set minimum threshold value, the quick frequency modulation function of the new energy station is temporarily locked for 0.2s, so that the false operation of frequency modulation is effectively prevented, and the frequency of the new energy station participating in the frequency modulation action is reduced;
simultaneously combined with TMAnd TLJudging whether to continuously lock the rapid frequency modulation function of the new energy station or not according to the calculation result, if T is judgedMAnd TLAny one of them is storedIn the same case (i.e. T)MOr TLLess than Tx) Continuously locking the function and considering the input of a broadband harmonic suppression strategy;
judging instantaneous voltage U of grid-connected pointHTime interval T between two adjacent zero crossingsHWhether the maximum threshold value T is larger than the set maximum threshold value T for 2 timesy(e.g. T)ySet to 9.5ms), if it is greater than the set maximum threshold TyThen, the rapid frequency modulation function of the new energy station is recovered;
the above steps are repeatedly executed.
As shown in fig. 3, a flowchart of a method for identifying an abnormal frequency of a new energy station under a broadband harmonic working condition specifically includes the following steps:
step 1: acquiring instantaneous voltage of a grid-connected point of a new energy station, instantaneous voltage of a 35kV/10kV bus in the station and instantaneous voltage of an outlet of a power generation unit at a fixed sampling rate, and recording the instantaneous voltages as UH、UMAnd UL；
Step 2: using the power frequency as a period and the next zero crossing point as a starting point to calculate the voltage instantaneous value U of the previous N power frequency periodsH、UMAnd UL(A, B, C three-phase voltage all need to be monitored) zero crossing number SH-、SM-、SL-If S isH-＝SM-＝SL-＝SXReturning to the step 1; if SH-＞SXEntering step 3; calculating S using equation (1)X. If the power frequency is set to 10 power frequency periods, SX＝21；
SX＝2N+1 (1)
Wherein N is the number of power frequency cycles, SXThe number of zero-crossing points in N power frequency periods.
And step 3: calculating the voltage instantaneous value U of the next power frequency period by taking the power frequency as a period and taking the next zero-crossing point as a starting pointH、UMAnd UL(A, B, C three-phase voltage all need to be monitored) zero crossing number SH+、SM+And SL+. If SH+＝SM+＝SL+And S isH+＝SXReturning to the step 1; if SH+＞SXEntering step 4;
and 4, step 4: calculating the time interval T between the voltage zero crossings of different electrical positions of the new energy station according to the formula (2)H+，TM+And TL+Calculating according to the formula (2);
TH+＝TH1+-TH2+ (2)
wherein, TH1+And TH2+Respectively the time coordinates of two adjacent zero crossings.
And 5: judgment of TH+Whether or not it is less than a set minimum threshold value Tx. If TH+＜TXTemporarily locking the function of fast frequency adjustment of the new energy station;
step 6: calculating TMAnd TLIf T is presentM＜TXOr TL＜TXContinuously locking the rapid frequency modulation adjusting function of the new energy station, and considering the broadband harmonic suppression strategy;
and 7: calculating the next power frequency period, THWhether it is greater than a set maximum threshold value Ty. If TH＞TyThen, the rapid frequency modulation and adjustment function of the new energy station is restarted;
and 8: and repeatedly executing the step 1 to the step 7.
The invention achieves the following effects:
(1) the method comprises the steps of quickly judging whether the main reason of frequency abnormality of the new energy station is power unbalance of a power system or broadband harmonic, and judging whether control strategies such as locking/inputting quick frequency modulation control, broadband harmonic suppression and the like are adopted;
(2) the acquired voltage instantaneous value is not subjected to filtering processing, and the frequency calculation result is closer to an actual value. When broadband harmonic waves (particularly 0-100Hz frequency band harmonic waves) exist in the system, the accuracy of frequency calculation is superior to the result of filtering processing, and reliable support is provided for fast frequency adjustment (inertia response and primary frequency modulation) of a wind power plant;
(3) and when the broadband harmonic is judged to be the leading factor, temporarily locking the rapid frequency modulation control strategy of the new energy station to avoid misoperation. The frequency of the new energy station participating in frequency modulation is effectively reduced, and the economy of the wind turbine generator, the energy storage device and the like is improved;
(4) the method is realized by optimizing a control strategy in software without increasing system hardware, and is convenient for field implementation;
(5) the method has good expansibility, can run in parallel with the existing frequency modulation control strategy, and has good portability.
Example 2:
the following is a description by a specific case.
The method runs in parallel with the existing fast frequency control strategy of the new energy station, and the 20kHz acquisition of the instantaneous voltage U of the grid-connected point of the new energy station is adopted in the embodiment by using a fixed sampling rateH35kV bus instantaneous voltage U in stationMAnd instantaneous voltage U at the outlet side of the power generation unit (wind turbine generator/photovoltaic inverter)LAnd the collected instantaneous voltage U of the grid-connected pointH35kV bus instantaneous voltage U in stationMAnd instantaneous voltage U at the outlet side of the power generation unit (wind turbine generator/photovoltaic inverter)LThe wind power plant fast frequency modulation controller is stored for standby;
the power frequency period is taken as the period, in the embodiment, 0.2s is taken as the power frequency period, and the instantaneous voltage U is calculatedH、UMAnd ULAnd preliminarily judging whether the abnormity exists or not; if the number of the zero crossing points is abnormal, entering the next step, otherwise returning to the previous step;
in the next power frequency period, U is calculated respectivelyH、UMAnd ULTime interval T between two adjacent zero crossingsH、TMAnd TL；
Judgment of THWhether it is less than the set minimum threshold value TxIn this embodiment, TxSet to 0.5ms if THIf the frequency is smaller than the set minimum threshold value, temporarily locking the rapid frequency modulation function of the new energy station for 0.02 s;
binding TMAnd TLJudging whether to continuously lock the rapid frequency modulation function of the new energy station according to the calculation result, if T is judgedMAnd TLAny 1 of themExceeds a set minimum threshold value TxIf yes, the function is locked continuously, and a trigger signal for inputting a broadband harmonic suppression strategy is given;
judge UHWhether the calculation result is greater than the set maximum threshold value T for 2 times continuouslyy(e.g. T)ySet to 9.5 ms); if the maximum threshold value is larger than the set maximum threshold value TyThen, the rapid frequency modulation function of the new energy station is recovered;
and repeating the steps.
Example 3
The invention based on the same inventive concept also provides a system for processing the abnormal frequency of the new energy station under the broadband harmonic working condition, which comprises:
the acquisition module is used for acquiring instantaneous voltages of different electrical position measurement points of the new energy station;
the calculation module is used for calculating the number of the zero-crossing points of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero-crossing points when the number of the zero-crossing points of the voltage is abnormal;
and the regulating and controlling module is used for determining locking and opening of the fast frequency modulation function of the new energy station based on the time interval between the two adjacent zero crossing points and a set threshold value.
The regulatory module comprises:
the temporary locking submodule is used for determining whether to lock the quick frequency modulation function of the new energy station temporarily or not based on the time interval of the instantaneous voltage of the grid-connected point and a set threshold;
the continuous locking sub-module is used for determining whether to continuously lock the new energy station rapid frequency modulation function or not based on the time interval of the instantaneous voltage of the bus in the station and/or the instantaneous voltage at the outlet side of the power generation unit and the set minimum threshold when the new energy station rapid frequency modulation function is temporarily locked;
the starting submodule is used for determining whether to start the rapid frequency modulation function of the new energy station or not based on the time interval of the instantaneous voltage of the grid-connected point and a set maximum threshold when the rapid frequency modulation function of the new energy station is continuously locked;
wherein the setting of the threshold value comprises setting a minimum threshold value and setting a maximum threshold value.
For convenience of description, each part of the above apparatus is separately described as each module or unit by dividing the function. Of course, the functionality of the various modules or units may be implemented in the same one or more pieces of software or hardware when implementing the present application.
Based on the same inventive concept, in yet another embodiment of the present invention, a computing device is provided, which includes a processor and a memory, the memory storing a computer program, the computer program including program instructions, the processor executing the program instructions stored by the computer storage medium. The Processor may be a Central Processing Unit (CPU), or may be other general-purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf Programmable gate array (FPGA) or other Programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, etc., which is a computing core and a control core of the terminal, and is specifically adapted to load and execute one or more instructions in a computer storage medium to implement a corresponding method flow or a corresponding function; the processor provided by the embodiment of the invention can be used for executing the steps of the new energy station abnormal frequency processing method under the broadband harmonic working condition.
Based on the same inventive concept, in yet another embodiment of the present invention, the present invention further provides a storage medium, specifically a computer-readable storage medium (Memory), which is a Memory device in a computer device and is used for storing programs and data. It is understood that the computer readable storage medium herein can include both built-in storage media in the computer device and, of course, extended storage media supported by the computer device. The computer-readable storage medium provides a storage space storing an operating system of the terminal. Also, one or more instructions, which may be one or more computer programs (including program code), are stored in the memory space and are adapted to be loaded and executed by the processor. It should be noted that the computer-readable storage medium may be a high-speed RAM memory, or may be a non-volatile memory (non-volatile memory), such as at least one disk memory. The processor may load and execute one or more instructions stored in the computer-readable storage medium to implement the corresponding steps of the method for processing the abnormal frequency of the new energy station under the broadband harmonic condition in the foregoing embodiments.
As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The present invention is not limited to the above embodiments, and any modifications, equivalent substitutions, improvements, etc. within the spirit and principle of the present invention are included in the scope of the claims of the present invention.

Claims (10)

1. A method for processing abnormal frequency of a new energy station under a broadband harmonic working condition is characterized by comprising the following steps:
acquiring instantaneous voltages of different electrical position measurement points of the new energy station;
calculating the number of zero crossings of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero crossings when the number of the zero crossings of the voltage is abnormal;
and determining locking and opening of the fast frequency modulation function of the new energy station based on the time interval between two adjacent zero-crossing points and a set threshold value.
2. The method of claim 1, wherein the acquiring instantaneous voltages of different electrical location measurement points of the new energy station comprises:
and acquiring instantaneous voltage of a grid-connected point of the new energy station, instantaneous voltage of a bus in the station and instantaneous voltage of an outlet side of a power generation unit.
3. The method according to claim 2, wherein the determining of the locking and unlocking of the new energy station fast frequency modulation function based on the time interval between the two adjacent zero-crossing points and the set minimum threshold value and the set maximum threshold value comprises:
determining whether to temporarily lock a new energy station fast frequency modulation function based on the time interval of the grid-connected point instantaneous voltage and a set minimum threshold;
when the new energy station rapid frequency modulation function is temporarily locked, determining whether the new energy station rapid frequency modulation function is continuously locked or not based on the time interval of the instantaneous voltage of the bus in the station and/or the instantaneous voltage at the outlet side of the power generation unit and the set minimum threshold;
when the rapid frequency modulation function of the new energy station is continuously locked, determining whether to start the rapid frequency modulation function of the new energy station based on the time interval of the instantaneous voltage of the grid-connected point and a set maximum threshold;
wherein the set threshold comprises a set minimum threshold and a set maximum threshold.
4. The method of claim 3, wherein determining whether to temporarily block a new energy station fast frequency tuning function based on the time interval of the grid-tie point instantaneous voltage and a set threshold comprises:
and temporarily locking the function of quickly modulating the frequency of the new energy station when the time interval of the instantaneous voltage of the grid-connected point is continuously less than a preset threshold value for at least two times.
5. The method according to claim 3, wherein the determining whether to continuously lock the new energy station fast frequency tuning function based on whether a time interval of a bus instantaneous voltage and/or a power generation unit outlet side instantaneous voltage in the station is less than the set threshold when the new energy station fast frequency tuning function is temporarily locked comprises:
and when the time interval of the instantaneous voltage of the bus in the station and/or the instantaneous voltage at the outlet side of the power generation unit is smaller than the set threshold value, the rapid frequency modulation function of the new energy station is continuously locked.
6. The method of claim 3, wherein determining whether to turn on the new energy station fast frequency modulation function based on the time interval of the grid-connected point instantaneous voltage and a set maximum threshold while continuously locking the new energy station fast frequency modulation function comprises:
and when the time interval of the instantaneous voltage of the grid-connected point is continuously greater than the set maximum threshold value for at least two times, starting the rapid frequency modulation function of the new energy station.
7. The method of claim 2, wherein the step of determining that the number of zero-crossing voltage points is abnormal comprises:
and when the zero crossing point number of the instantaneous voltage of the grid-connected point, the instantaneous voltage of the bus in the station and the instantaneous voltage at the outlet side of the power generation unit is greater than the zero crossing point number corresponding to the power frequency cycle, judging that the zero crossing point number of the voltage is abnormal.
8. The method of claim 7, wherein the number of zero-crossing points corresponding to the power frequency cycle is calculated as follows:
SX＝2N+1
in the formula, N is the number of power frequency cycles.
9. The utility model provides a new forms of energy field station abnormal frequency processing system under wide band harmonic operating mode which characterized in that includes:
the acquisition module is used for acquiring instantaneous voltages of different electrical position measurement points of the new energy station;
the calculation module is used for calculating the number of the zero-crossing points of the instantaneous voltage by taking the power frequency as a period, and calculating the time interval between two adjacent zero-crossing points when the number of the zero-crossing points of the voltage is abnormal;
and the regulating and controlling module is used for determining locking and opening of the fast frequency modulation function of the new energy station based on the time interval between the two adjacent zero crossing points and a set threshold value.
10. The system of claim 9, wherein the regulatory module comprises:
the temporary locking submodule is used for determining whether to lock the quick frequency modulation function of the new energy station temporarily or not based on the time interval of the instantaneous voltage of the grid-connected point and a set threshold;
the continuous locking sub-module is used for determining whether to continuously lock the rapid frequency modulation function of the new energy station based on the time interval of the instantaneous voltage of the bus in the station and/or the instantaneous voltage at the outlet side of the power generation unit and the set minimum threshold when the rapid frequency modulation function of the new energy station is temporarily locked;
the starting submodule is used for determining whether to start the rapid frequency modulation function of the new energy station or not based on the time interval of the instantaneous voltage of the grid-connected point and a set maximum threshold value when the rapid frequency modulation function of the new energy station is continuously locked;
wherein the set threshold comprises a set minimum threshold and a set maximum threshold.
CN202111395099.6A 2021-11-23 2021-11-23 Method and system for processing abnormal frequency of new energy station under broadband harmonic working condition Pending CN114188946A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115166585A (en) * 2022-09-08 2022-10-11 石家庄科林电气股份有限公司 Ground fault detection anti-misjudgment method and device and electronic equipment

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115166585A (en) * 2022-09-08 2022-10-11 石家庄科林电气股份有限公司 Ground fault detection anti-misjudgment method and device and electronic equipment
CN115166585B (en) * 2022-09-08 2022-11-29 石家庄科林电气股份有限公司 Ground fault detection anti-misjudgment method and device and electronic equipment

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