CN109088443A - The mistake of field regulator encourages limitation optimization method and system - Google Patents
The mistake of field regulator encourages limitation optimization method and system Download PDFInfo
- Publication number
- CN109088443A CN109088443A CN201810914015.7A CN201810914015A CN109088443A CN 109088443 A CN109088443 A CN 109088443A CN 201810914015 A CN201810914015 A CN 201810914015A CN 109088443 A CN109088443 A CN 109088443A
- Authority
- CN
- China
- Prior art keywords
- excitation
- result
- numerical value
- calculation result
- comparison
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 33
- 238000005457 optimization Methods 0.000 title claims abstract description 20
- 230000005284 excitation Effects 0.000 claims abstract description 145
- 238000004364 calculation method Methods 0.000 claims description 103
- 230000000670 limiting effect Effects 0.000 claims description 57
- 238000004590 computer program Methods 0.000 claims description 11
- 238000012545 processing Methods 0.000 claims description 9
- 230000009466 transformation Effects 0.000 claims description 4
- 238000012360 testing method Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 5
- 238000013461 design Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000006399 behavior Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- 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
- H02J3/50—Controlling the sharing of the out-of-phase component
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
- H02P9/14—Arrangements for controlling electric generators for the purpose of obtaining a desired output by variation of field
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Eletrric Generators (AREA)
Abstract
The mistake that the present invention provides a kind of field regulator encourages limitation optimization method and system.The mistake of the field regulator encourages limitation optimization method and comprises determining that inertia time constant；The exciting current for acquiring generator calculates the first calculated result according to inertia time constant and exciting current；The size for comparing the first calculated result and the first fiducial value obtains the first comparison result, determines output result according to the first comparison result；When exporting result is second value, started and encourages the adjusting of limitation inverse time lag to reduce exciting current to the first preset value, different time inverse time lag can be adjusted according to initial excitation electric current different before failure, i.e. in underrun, make unit have it is higher encourage ability by force, in heavy-duty service, have unit and lower encourage ability by force, abundant reactive power support appropriate is provided to guarantee power grid in multiple cascading failure, maintains electric power netting safe running.
Description
Technical Field
The invention relates to the field of excitation regulation, in particular to an excitation limit optimization method and system of an excitation regulator.
Background
Insufficient voltage reactive support capability under severe fault impact may induce system voltage instability accidents. The action behavior of Over Excitation Limit (OEL) of the generator in the middle and long-term fault process plays an important role in maintaining the stability of the power grid and preventing large-area power failure accidents.
At present, a great deal of research is carried out on the influence of overexcitation limitation on cascading blackout accidents, the problems of overexcitation protection coordination and the like. The inverse time limit time in the existing design is irrelevant to the initial value of the exciting current and only relevant to the exciting current value during strong excitation, so that when the initial exciting current of the generator is lower than the rated exciting current, the strong excitation capability or over-current potential capability of the generator is far higher than that of the existing conventional excitation design, and the supporting capability of a unit to a power grid cannot be fully exerted; when the initial excitation current of the generator is higher than the rated excitation current, the strong excitation capacity of the generator is smaller than that of the conventional excitation design, and the safety of the unit can be endangered.
Disclosure of Invention
The embodiment of the invention mainly aims to provide an excitation limiting optimization method and system of an excitation regulator, so as to ensure that a power grid provides sufficient and appropriate reactive support when multiple cascading failures occur, and maintain the safe operation of the power grid.
In order to achieve the above object, an embodiment of the present invention provides a method for optimizing an excitation limit of an excitation regulator, including:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with the first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein, the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the excitation current to the first preset value.
The embodiment of the invention also provides an excitation limit optimization system of the excitation regulator, which comprises the following steps:
a determination unit for determining an inertia time constant;
the first calculation unit is used for acquiring the exciting current of the generator and calculating a first calculation result according to the inertia time constant and the exciting current;
the comparison unit is used for comparing the first calculation result with the first comparison value to obtain a first comparison result;
an output result unit for determining an output result according to the first comparison result; wherein, the output result is a first numerical value or a second numerical value;
and the over-excitation limiting adjusting unit is used for starting the over-excitation limiting inverse time limit adjustment to reduce the exciting current to a first preset value.
The embodiment of the present invention further provides a computer device, which includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor, and when the processor executes the computer program, the following steps are implemented:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with the first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein, the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the excitation current to the first preset value.
An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the following steps:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with the first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein, the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the excitation current to the first preset value.
The invention discloses an over-excitation limit optimization method and system of an excitation regulator, which comprises the steps of firstly determining an inertia time constant, then collecting excitation current of a generator, calculating a first calculation result according to the inertia time constant and the excitation current, finally comparing the first calculation result with a first comparison value to obtain a first comparison result, determining an output result according to the first comparison result, starting over-excitation limit inverse time limit regulation to reduce the excitation current to a first preset value when the output result is a second value, adjusting different inverse time limit times according to different initial excitation currents before a fault, namely enabling a unit to have higher strong excitation capacity when in low-load operation, enabling the unit to have lower strong excitation capacity when in high-load operation, and ensuring that a power grid provides fully proper reactive support when multiple cascading faults exist so as to maintain safe operation of the power grid.
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 will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained based on these drawings without creative efforts.
FIG. 1 is a flow chart of a method for optimizing an over-excitation limit of an excitation regulator in an embodiment of the present invention;
FIG. 2 is a detailed flowchart of S104 in the embodiment of the present invention;
FIG. 3 is a logic diagram of a method of optimizing the overdrive limit of an excitation regulator in accordance with an embodiment of the present invention;
FIG. 4 is a chart of the excitation current waveform for a voltage step test;
FIG. 5 is a table of the inverse time-limited actuation of the overdriving limit for different excitation currents;
FIG. 6 is a graph of the terminal voltage waveform under the cascading failure test;
FIG. 7 is a recording diagram of the exciting current under the cascading failure test;
FIG. 8 is a block diagram of an overdrive limiting optimization system for an excitation regulator in an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. 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.
In view of the fact that the prior art cannot fully exert the supporting capability of the unit on the power grid and possibly endanger the safety of the unit, the embodiment of the invention provides the over-excitation limiting optimization method of the excitation regulator, so that the power grid can be guaranteed to provide fully proper reactive power support when multiple cascading failures happen, and the safe operation of the power grid can be maintained. The present invention will be described in detail below with reference to the accompanying drawings.
FIG. 1 is a flow chart of a method for optimizing the over-excitation limit of an excitation regulator in an embodiment of the present invention. As shown in fig. 1, the method for optimizing the over-excitation limit of the field regulator includes:
s101: an inertial time constant is determined.
S102: the method comprises the steps of collecting the exciting current of the generator, and calculating a first calculation result according to an inertia time constant and the exciting current.
S103: and comparing the first calculation result with the first comparison value to obtain a first comparison result.
S104: and determining an output result according to the first comparison result, wherein the output result is a first numerical value or a second numerical value.
S105: and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the excitation current to the first preset value.
The execution subject of the method of optimizing the excitation limit of the field regulator shown in fig. 1 may be the field regulator. As can be seen from the flowchart shown in fig. 1, the method for optimizing the over-excitation limit of the field regulator according to the embodiment of the present invention determines the inertia time constant first, then collecting the exciting current of the generator, calculating a first calculation result according to the inertia time constant and the exciting current, finally comparing the first calculation result with a first comparison value to obtain a first comparison result, determining an output result according to the first comparison result, starting overexcitation limit inverse time limit adjustment to reduce the excitation current to a first preset value when the output result is a second value, adjusting different inverse time limit times according to different initial excitation currents before a fault, namely, the unit has higher strong excitation capacity when in low-load operation and has lower strong excitation capacity when in high-load operation, the system can ensure that the power grid provides sufficient and proper reactive support when multiple cascading failures occur, and the safe operation of the power grid is maintained.
In one embodiment, the time constant of inertia is determined by the following equation:
wherein T is an inertia time constant, TIs time of day, IfExcitation current at positive infinity, (∞)f(0-) Excitation current at time 0, IfthIs 1.1 times of rated exciting current.
In an embodiment, S102 specifically includes:
carrying out Laplace transformation on the exciting current; a first calculation result is calculated from the Laplace-transformed excitation current and the inertia time constant.
Wherein the first calculation result is calculated by the following formula:
wherein,as a result of the first calculation, If(s) is the Laplace transformed excitation current, T is the inertia time constant, and s is the Laplace operator.
Fig. 2 is a detailed flowchart of S104 in the embodiment of the present invention. As shown in fig. 2, S104 includes:
s201: and performing gain processing and amplitude limiting processing on the first comparison result to obtain an amplitude limiting result.
S202: and obtaining a second calculation result according to the amplitude limiting result and the condition parameter.
S203: and comparing the second calculation result with the second preset value to obtain an output result.
In one embodiment, the condition parameter is a third value or a fourth value. S202 specifically includes:
when the machine terminal voltage meets the secondary forced excitation adjusting condition, the condition parameter is a third numerical value, and a second calculation result is obtained according to the amplitude limiting result and the third numerical value; and when the machine terminal voltage does not meet the secondary forced excitation regulation condition, the condition parameter is a fourth numerical value, and a second calculation result is obtained according to the amplitude limiting result and the fourth numerical value.
And multiplying the amplitude limiting result by the condition parameter to obtain a second calculation result, wherein the third value is 0, the fourth value is 1, and the amplitude limiting result is 0 or 1.
In one embodiment, when the second calculation result is smaller than a second preset value, the output result is a first numerical value; and when the second calculation result is greater than or equal to a second preset value, outputting a result as a second numerical value. Wherein the second preset value is 0.99. The second calculation result is 0 or 1, the first value is 0, and the second value is 1.
In one embodiment, when the output result is the second value, the first calculation result at the current time is compared with the second comparison value, when the first calculation result at the current time is smaller than the second comparison value, the output result is the first value, and at this time, the overdrive limit inverse time limit reset is started.
In one embodiment, when the first calculation result at the current moment is greater than or equal to the second comparison value and the generator terminal voltage meets the secondary forced excitation regulation condition, the forced excitation regulation is started to increase the excitation current.
Wherein, the secondary forced excitation adjusting conditions are as follows:Utthe terminal voltage of the generator at time t.
FIG. 3 is a logic diagram of a method of optimizing the overdrive limit of an excitation regulator in accordance with an embodiment of the present invention. As shown in fig. 3, the specific process of the embodiment of the present invention is as follows:
1. the time constant of inertia is determined by the following equation:
wherein,Ifnis rated exciting current. When the invention can meet the condition that the initial exciting current is IfnAt 2 times IfnWhen the strong excitation lasts for 10s, t is 10s, and the time is
2. For exciting current IfPerforming a laplace transform; calculating a first calculation result from the Laplace-transformed excitation current and the inertia time constant
3. At the initial normal time, the result S is outputOELWhen the first calculation result is compared with the first comparison value, the first comparison result is obtained. Wherein the first comparison result is a first calculation resultAnd a first comparison valueThe first comparison value is 1.21. When the first calculation result is greater than or equal to the first comparison value, the first comparison result is greater than 0. When the first calculation result is smaller than the first comparison value, the first comparison result is smaller than 0.
4. as shown in fig. 3, the value of the gain K is very large, when the first comparison result is greater than 0, the value obtained by multiplying the first comparison result by K is greater than 1, and the amplitude-limiting result △ I obtained through the amplitude-limiting processing isf 2is 1, when the first comparison result is less than 0, the value obtained by multiplying the first comparison result by K is less than 0, and the amplitude limiting result △ I is obtained by amplitude limiting treatmentf 2Is 0.
5. Obtaining a second calculation result according to the amplitude limiting result and the condition parameter. Under normal working conditions, the terminal voltage does not meet the secondary forced excitation regulation condition,at this time, the condition parameter SUtIs 1. Comparing the second calculation result with a second preset value (0.99), and when the second calculation result is 0, outputting a result of 0, wherein the system is normal; when the second calculation result is 1, the output result is 1.
6. When outputting the result SOELWhen the time is 1, the inverse time limit timing is shown to meet the overexcitation limiting action condition, and the overexcitation limiting regulation link is started to reduce the excitation current If1.1p.u. to a first preset value to protect the generator equipment; at the same time, the first comparison value is comparedSwitch to the second comparison valueThe second comparison value is 1.12, the first calculation result is greater than or equal to the second comparison value, and the result S is outputOELRemains at 1.
7. When the fault is recovered, the exciting current IfReducing the first calculation result, outputting the result to be 0 when the first calculation result is smaller than the second comparison value, starting the overdrive limit inverse time limit reset, and comparing the second comparison valueSwitch to the first comparison value
When the original system fault is not recovered and the fault (cascading fault) occurs again, the first calculation result is greater than or equal to the second comparison value and the terminal voltage meets the secondary forced excitation regulation condition,the conditions are as followsNumber SUtChanging from 1 to 0, outputting 0, switching the second comparison value to the first comparison value, and switching back to the strong excitation regulation from the over excitation limitation inverse time limit regulation to increase the excitation current If. And when the first calculation result is greater than or equal to the first comparison value and the terminal voltage does not meet the secondary forced excitation regulation condition, changing the output result from 0 to 1, starting the over-excitation limiting inverse time limit regulation again, and repeating the step 6.
Taking PSASP simulation software as an example, a single-computer infinite simulation system is built to verify the superiority of the invention. Fig. 4 is a graph of the excitation current waveform in the voltage step test. As shown in FIG. 4, the initial excitation currents were 1.05I, respectivelyfn、1.0Ifn、0.75Ifn、0.5Ifn(IfnCorresponding to ordinate 2.7p.u. in fig. 4), voltage step tests were carried out at the same time, so that the excitation currents all rose to 2.0Ifn. As can be seen from FIG. 4, after different back-time periods, the over-excitation limiting back-time period is normally adjusted to limit the exciting current to 1.1Ifn. Fig. 5 is a table of the over-excitation limit inverse time-limited action time at different initial excitation currents. As shown in fig. 5, under the same excitation current over-excitation multiple, the actual operation time of the embodiment of the present invention depends on the initial excitation current, and compared with the scheme that the theoretical inverse time limit operation times of the prior art are all 10s, the present invention fully considers the overheating capability of the generator rotor under different excitation currents, and can adjust different inverse time limit times according to different initial excitation currents before the fault, that is, when the unit is in low-load operation, the unit has higher strong excitation capability, and when the unit is in high-load operation, the unit has lower strong excitation capability, so as to ensure that the grid provides sufficient and appropriate reactive support when multiple cascading faults occur, and maintain the safe operation of the grid.
Fig. 6 is a graph of the terminal voltage waveform under the cascading failure test. Fig. 7 is a waveform chart of the excitation current in the cascading failure test. As shown in fig. 6 and 7, under the full-load condition of the generator, at the 5 th simulated system voltage step, the terminal voltage drops to 0.84p.u., at which time the excitation system is excited by force, and the excitation current rises to 2.0IfnAfter 10.9s, OEL (over-excitation limiting) operation was performed, and the terminal voltage was reduced to 0.69p.u. rotor current return to 1.1Ifn. On the basis, a second fault is simulated, namely a three-phase instantaneous short-circuit fault of 100ms occurs at 80% of a certain power transmission line at the moment of 40s, so that the fault is causedAt the moment, the over-excitation limiting inverse time limit adjustment is switched back to the forced excitation adjustment for secondary forced excitation, and the terminal voltage and the exciting current stably run after the instantaneous short circuit; and if the secondary forced excitation function is shielded, the terminal voltage and the excitation current oscillation at the instant short circuit end are dispersed, so that the system is broken down. Therefore, when cascading failure occurs, the invention can provide strong excitation current in a short time, improve the stability of the system and ensure the safe and stable operation of the power grid.
To sum up, the method for optimizing the overexcitation limit of the excitation regulator according to the embodiment of the present invention determines an inertia time constant, acquires an excitation current of the generator, calculates a first calculation result according to the inertia time constant and the excitation current, compares the first calculation result with a first comparison value to obtain a first comparison result, determines an output result according to the first comparison result, starts the overexcitation limit inverse time limit adjustment to reduce the excitation current to a first preset value when the output result is a second value, and can adjust different inverse time limit times according to different initial excitation currents before a fault, that is, when the unit operates at a low load, the unit has a high overexcitation capability, and when the unit operates at a high load, the unit has a low overexcitation capability to ensure that a power grid provides sufficient and appropriate reactive support when multiple times of cascading faults, and maintain safe operation of the power grid.
According to the excitation regulator over-excitation limiting optimization method, secondary strong excitation is carried out when the system has cascading failure, so that terminal voltage and excitation current stably operate, the stability of the system is improved, and the safe and stable operation of a power grid is guaranteed.
Based on the same inventive concept, the embodiment of the invention also provides an excitation limiting optimization system of the excitation regulator, and as the principle of solving the problems of the system is similar to the excitation limiting optimization method of the excitation regulator, the implementation of the system can refer to the implementation of the method, and repeated parts are not described again.
FIG. 8 is a block diagram of an overdrive limiting optimization system for an excitation regulator in an embodiment of the present invention. As shown in fig. 8, the excitation limit optimizing system of the excitation regulator includes:
a determination unit for determining an inertia time constant;
the first calculation unit is used for acquiring the exciting current of the generator and calculating a first calculation result according to the inertia time constant and the exciting current;
the comparison unit is used for comparing the first calculation result with the first comparison value to obtain a first comparison result;
an output result unit for determining an output result according to the first comparison result; wherein, the output result is a first numerical value or a second numerical value;
and the over-excitation limiting adjusting unit is used for starting the over-excitation limiting inverse time limit adjustment to reduce the exciting current to a first preset value.
In one embodiment, the inertial time constant is determined by the following equation:
wherein T is an inertia time constant, T is a time, IfExcitation current at positive infinity, (∞)f(0-) Excitation current at time 0, IfthIs 1.1 times of rated exciting current.
In one embodiment, the first computing unit is specifically configured to:
carrying out Laplace transformation on the exciting current;
calculating a first calculation result according to the excitation current subjected to Laplace transform and an inertia time constant;
wherein the first calculation result is calculated by the following formula:
wherein,as a result of the first calculation, If(s) is the Laplace transformed excitation current, T is the inertia time constant, and s is the Laplace operator.
In one embodiment, the output result unit includes:
the amplitude limiting result subunit is used for performing gain processing and amplitude limiting processing on the first comparison result to obtain an amplitude limiting result;
the second calculation subunit is used for obtaining a second calculation result according to the amplitude limiting result and the condition parameter;
and the output result unit subunit is used for comparing the second calculation result with the second preset value to obtain an output result.
In one embodiment, the condition parameter is a third value or a fourth value;
the second calculating subunit is specifically configured to:
obtaining a second calculation result according to the amplitude limiting result and the third numerical value;
and obtaining a second calculation result according to the amplitude limiting result and the fourth value.
In one embodiment, when the second calculation result is smaller than a second preset value, the output result is a first numerical value;
and when the second calculation result is greater than or equal to a second preset value, outputting a result as a second numerical value.
In one embodiment, the method further comprises the following steps: an overdriving limitation inverse time limit reset unit;
the overdriving limit adjusting unit is also used for: switching the first comparison value to a second comparison value;
the comparison unit is further configured to: comparing the first calculation result at the current moment with the second comparison value;
the overdriving limitation inverse time limit reset unit is used for: and starting the overdriving limit inverse time limit reset, and switching the second comparison value to the first comparison value.
In one embodiment, the method further comprises the following steps:
and the forced excitation adjusting unit is used for starting forced excitation adjustment to increase the excitation current.
To sum up, the overexcitation limit optimization system of the excitation regulator in the embodiment of the present invention first determines an inertia time constant, then collects an excitation current of the generator, calculates a first calculation result according to the inertia time constant and the excitation current, and finally compares the first calculation result with a first comparison value to obtain a first comparison result, determines an output result according to the first comparison result, and when the output result is a second value, starts overexcitation limit inverse time limit adjustment to reduce the excitation current to a first preset value, and can adjust different inverse time limit times according to different initial excitation currents before a fault, that is, when the unit operates at a low load, the unit has a high overexcitation capability, and when the unit operates at a high load, the unit has a low overexcitation capability, so as to ensure that a power grid provides sufficient and appropriate reactive support when multiple times of cascading faults, and maintain safe operation of the power grid.
The over-excitation limiting optimization system of the excitation regulator provided by the embodiment of the invention performs secondary strong excitation when the system has cascading failure, so that the terminal voltage and the excitation current stably operate, the stability of the system is improved, and the safe and stable operation of a power grid is ensured.
The embodiment of the present invention further provides a computer device, which includes a memory, a processor, and a computer program stored in the memory and capable of running on the processor, and when the processor executes the computer program, the following steps are implemented:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with the first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein, the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the excitation current to the first preset value.
To sum up, the computer device of the embodiment of the present invention first determines an inertia time constant, then collects an excitation current of a generator, calculates a first calculation result according to the inertia time constant and the excitation current, and finally compares the first calculation result with a first comparison value to obtain a first comparison result, determines an output result according to the first comparison result, when the output result is a second value, starts an overexcitation limitation inverse time limit adjustment to reduce the excitation current to a first preset value, and can adjust different inverse time limit times according to different initial excitation currents before a fault, that is, when the computer device operates at a low load, the computer device enables the computer device to have a higher overexcitation capability, when the computer device operates at a high load, the computer device ensures that a power grid provides a fully appropriate reactive support when multiple cascading faults, and maintains safe operation of the power grid.
An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the following steps:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with the first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein, the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the excitation current to the first preset value.
To sum up, the computer-readable storage medium of the embodiment of the present invention first determines an inertia time constant, then collects an excitation current of a generator, calculates a first calculation result according to the inertia time constant and the excitation current, and finally compares the first calculation result with a first comparison value to obtain a first comparison result, determines an output result according to the first comparison result, when the output result is a second value, starts an overexcitation limitation inverse time limit adjustment to reduce the excitation current to a first preset value, and can adjust different inverse time limit times according to different initial excitation currents before a fault, that is, when the unit operates at a low load, the unit has a high overexcitation capability, and when the unit operates at a high load, the unit has a low overexcitation capability to ensure that a power grid provides a sufficient and appropriate reactive support when multiple cascading faults occur, and to maintain safe operation of the power grid.
The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (18)
1. A method of optimizing an overdrive limit of an excitation regulator, comprising:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with a first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the exciting current to a first preset value.
2. The method of optimizing the overdrive restriction of the field regulator according to claim 1, wherein the inertia time constant is determined by the following formula:
wherein T is an inertia time constant, T is a time, IfExcitation current at positive infinity, (∞)f(0-) Excitation current at time 0, IfthIs 1.1 times of rated exciting current.
3. The method for optimizing the overexcitation limit of an excitation regulator according to claim 1, wherein the calculating a first calculation result from the inertia time constant and the excitation current includes:
performing Laplace transformation on the excitation current;
calculating a first calculation result according to the excitation current subjected to the Laplace transform and the inertia time constant;
wherein the first calculation result is calculated by the following formula:
wherein,as a result of the first calculation, If(s) is the Laplace transformed excitation current, T is the inertia time constant, and s is the Laplace operator.
4. The method for optimizing the overdrive restriction of an excitation regulator according to claim 1, wherein determining an output result according to the first comparison result specifically includes:
performing gain processing and amplitude limiting processing on the first comparison result to obtain an amplitude limiting result;
obtaining a second calculation result according to the amplitude limiting result and the condition parameter;
and comparing the second calculation result with a second preset value to obtain an output result.
5. The method of optimizing an over-excitation limit of an excitation regulator according to claim 4,
the condition parameter is a third numerical value or a fourth numerical value;
obtaining a second calculation result according to the amplitude limiting result and the condition parameter, specifically comprising:
when the machine terminal voltage meets the secondary forced excitation adjusting condition, the condition parameter is the third numerical value, and the second calculation result is obtained according to the amplitude limiting result and the third numerical value;
and when the machine terminal voltage does not meet the secondary forced excitation regulation condition, the condition parameter is the fourth numerical value, and the second calculation result is obtained according to the amplitude limiting result and the fourth numerical value.
6. The method of optimizing an over-excitation limit of an excitation regulator according to claim 4,
when the second calculation result is smaller than the second preset value, the output result is the first numerical value;
and when the second calculation result is greater than or equal to the second preset value, the output result is the second numerical value.
7. The method of optimizing an over-excitation limit of an excitation regulator according to claim 1,
and when the output result is the second numerical value, comparing the first calculation result and the second comparison value at the current moment, and when the first calculation result is smaller than the second comparison value, the output result is the first numerical value, and starting the overdrive limit inverse time limit reset.
8. The method of optimizing an over-excitation limit of an excitation regulator according to claim 7,
and when the first calculation result at the current moment is greater than or equal to the second comparison value and the terminal voltage meets the secondary forced excitation regulation condition, starting forced excitation regulation to increase the excitation current.
9. An over-excitation limit optimization system for an excitation regulator, comprising:
a determination unit for determining an inertia time constant;
the first calculation unit is used for acquiring the exciting current of the generator and calculating a first calculation result according to the inertia time constant and the exciting current;
the comparison unit is used for comparing the first calculation result with a first comparison value to obtain a first comparison result;
the output result unit is used for determining an output result according to the first comparison result; wherein the output result is a first numerical value or a second numerical value;
and the over-excitation limiting adjusting unit is used for starting the over-excitation limiting inverse time limit adjustment so as to reduce the exciting current to a first preset value.
10. The over-excitation limit optimization system of the field regulator according to claim 9, wherein the inertia time constant is determined by the following formula:
wherein T is an inertia time constant, T is a time, IfExcitation current at positive infinity, (∞)f(0-) Excitation current at time 0, IfthIs 1.1 times of rated exciting current.
11. The system of claim 9, wherein the first computing unit is specifically configured to:
performing Laplace transformation on the excitation current;
calculating a first calculation result according to the excitation current subjected to the Laplace transform and the inertia time constant;
wherein the first calculation result is calculated by the following formula:
wherein,as a result of the first calculation, If(s) is the Laplace transformed excitation current, T is the inertia time constant, and s is the Laplace operator.
12. The system of claim 9, wherein the output result unit comprises:
the amplitude limiting result subunit is used for performing gain processing and amplitude limiting processing on the first comparison result to obtain an amplitude limiting result;
the second calculation subunit is used for obtaining a second calculation result according to the amplitude limiting result and the condition parameter;
and the output result unit subunit is used for comparing the second calculation result with a second preset value to obtain an output result.
13. The excitation regulator over-excitation limit optimization system according to claim 12,
the condition parameter is a third numerical value or a fourth numerical value;
the second calculating subunit is specifically configured to:
obtaining the second calculation result according to the amplitude limiting result and the third numerical value;
and obtaining the second calculation result according to the amplitude limiting result and the fourth numerical value.
14. The excitation regulator over-excitation limit optimization system according to claim 12,
when the second calculation result is smaller than the second preset value, the output result is the first numerical value;
and when the second calculation result is greater than or equal to the second preset value, the output result is the second numerical value.
15. The system of claim 9, further comprising: an overdriving limitation inverse time limit reset unit;
the comparison unit is further configured to: comparing the first calculation result at the current moment with the second comparison value;
the overdriving limitation inverse time limit reset unit is used for: an overdrive limited inverse time limit reset is initiated.
16. The system of claim 15, further comprising:
and the forced excitation adjusting unit is used for starting forced excitation adjustment to increase the excitation current.
17. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor when executing the computer program implements the steps of:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with a first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the exciting current to a first preset value.
18. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of:
determining an inertia time constant;
collecting the exciting current of the generator, and calculating a first calculation result according to the inertia time constant and the exciting current;
comparing the first calculation result with a first comparison value to obtain a first comparison result, and determining an output result according to the first comparison result; wherein the output result is a first numerical value or a second numerical value;
and when the output result is the second numerical value, starting the over-excitation limiting inverse time limit adjustment to reduce the exciting current to a first preset value.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810914015.7A CN109088443B (en) | 2018-08-13 | 2018-08-13 | Over-excitation limit optimization method and system for excitation regulator |
| PCT/CN2018/119090 WO2020034491A1 (en) | 2018-08-13 | 2018-12-04 | Overexcitation limiting method and system for excitation regulator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810914015.7A CN109088443B (en) | 2018-08-13 | 2018-08-13 | Over-excitation limit optimization method and system for excitation regulator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109088443A true CN109088443A (en) | 2018-12-25 |
| CN109088443B CN109088443B (en) | 2020-06-05 |
Family
ID=64834385
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810914015.7A Active CN109088443B (en) | 2018-08-13 | 2018-08-13 | Over-excitation limit optimization method and system for excitation regulator |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN109088443B (en) |
| WO (1) | WO2020034491A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110932626A (en) * | 2019-12-05 | 2020-03-27 | 国网冀北电力有限公司电力科学研究院 | Auxiliary limit control method and device for alternating current excitation system of variable-speed pumping and storage unit |
| CN112467754A (en) * | 2019-09-06 | 2021-03-09 | 南京南瑞继保电气有限公司 | Phase modulator excitation feed-forward type forced excitation control method |
| CN113037156A (en) * | 2021-03-09 | 2021-06-25 | 南京航空航天大学 | Control method of hybrid excitation generator |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102255594A (en) * | 2011-08-05 | 2011-11-23 | 国电南瑞科技股份有限公司 | Main and auxiliary link cooperative control method for generator excitation system |
| CN103516278A (en) * | 2013-09-26 | 2014-01-15 | 国家电网公司 | Excitation system full-function-performance simulation system based on MATLAB |
| CN103516274A (en) * | 2013-09-26 | 2014-01-15 | 国家电网公司 | Generator excitation system comprising multi-type limiting units |
| CN106533290A (en) * | 2016-11-24 | 2017-03-22 | 华北电力科学研究院有限责任公司 | Stator current limiting method and apparatus for generator automatic voltage regulator |
| CN107834922A (en) * | 2017-11-08 | 2018-03-23 | 华北电力科学研究院有限责任公司 | A kind of condition control method and device of the limitation of field regulator stator current |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102364801A (en) * | 2011-05-04 | 2012-02-29 | 国网电力科学研究院 | Four-quadrant reactive power control method for excitation system of pumped storage unit |
| CN103248301A (en) * | 2012-02-09 | 2013-08-14 | 武汉洪山电工科技有限公司 | Microcomputer excitation regulator capable of automatically setting control parameter |
| CN104428989B (en) * | 2012-09-19 | 2017-06-23 | 三菱电机株式会社 | Field winding type rotary electric machine |
| CN107104448B (en) * | 2017-05-18 | 2020-10-02 | 辽宁石油化工大学 | Power system stabilizer and method |
-
2018
- 2018-08-13 CN CN201810914015.7A patent/CN109088443B/en active Active
- 2018-12-04 WO PCT/CN2018/119090 patent/WO2020034491A1/en active Application Filing
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102255594A (en) * | 2011-08-05 | 2011-11-23 | 国电南瑞科技股份有限公司 | Main and auxiliary link cooperative control method for generator excitation system |
| CN103516278A (en) * | 2013-09-26 | 2014-01-15 | 国家电网公司 | Excitation system full-function-performance simulation system based on MATLAB |
| CN103516274A (en) * | 2013-09-26 | 2014-01-15 | 国家电网公司 | Generator excitation system comprising multi-type limiting units |
| CN106533290A (en) * | 2016-11-24 | 2017-03-22 | 华北电力科学研究院有限责任公司 | Stator current limiting method and apparatus for generator automatic voltage regulator |
| CN107834922A (en) * | 2017-11-08 | 2018-03-23 | 华北电力科学研究院有限责任公司 | A kind of condition control method and device of the limitation of field regulator stator current |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112467754A (en) * | 2019-09-06 | 2021-03-09 | 南京南瑞继保电气有限公司 | Phase modulator excitation feed-forward type forced excitation control method |
| CN112467754B (en) * | 2019-09-06 | 2022-07-22 | 南京南瑞继保电气有限公司 | Phase modulator excitation feed-forward type forced excitation control method |
| CN110932626A (en) * | 2019-12-05 | 2020-03-27 | 国网冀北电力有限公司电力科学研究院 | Auxiliary limit control method and device for alternating current excitation system of variable-speed pumping and storage unit |
| CN110932626B (en) * | 2019-12-05 | 2021-06-18 | 国网冀北电力有限公司电力科学研究院 | Auxiliary limit control method and device for alternating current excitation system of variable-speed pumping and storage unit |
| CN113037156A (en) * | 2021-03-09 | 2021-06-25 | 南京航空航天大学 | Control method of hybrid excitation generator |
| CN113037156B (en) * | 2021-03-09 | 2022-06-14 | 南京航空航天大学 | Control method of hybrid excitation generator |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109088443B (en) | 2020-06-05 |
| WO2020034491A1 (en) | 2020-02-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109088443B (en) | Over-excitation limit optimization method and system for excitation regulator | |
| Li et al. | Enhanced FRT and postfault recovery control for MMC-HVDC connected offshore wind farms | |
| US20210216698A1 (en) | Insulation coordination method and system for a series compensation apparatus, storage medium and electronic device | |
| Yan et al. | Frequency response and its enhancement using synchronous condensers in presence of high wind penetration | |
| CN107834922B (en) | A kind of condition control method and device of the limitation of field regulator stator current | |
| CN114039499A (en) | Commutation control method and device of converter, electronic equipment and readable storage medium | |
| Bera et al. | Sizing of energy storage systems for grid inertial response | |
| CN106921177B (en) | Low voltage ride through control method and device of wind generating set and simulation system | |
| Pajuelo et al. | Coordination of overexcitation limiter, field overcurrent protection and generator control | |
| Tzelepis et al. | Impact of synchronous condensers on transmission line protection in scenarios with high penetration of renewable energy sources | |
| Yagami et al. | Transient stability assessment of synchronous generator in power system with high-penetration photovoltaics (Part 2) | |
| CN116865252A (en) | Transient stability control and analysis method based on network-structured VSC current limiting strategy | |
| Safavizadeh et al. | Investigation of torque-angle characteristics of synchronous generators for transient stability analysis using equal area criterion | |
| Nguyen-Duc et al. | Effect of DFIG wind farm fault currents on the transformer differential relaying performance | |
| CN110867828B (en) | Method and device for positioning turn-to-turn fault of energy-pumping reactor | |
| Huang et al. | Optimal capacity allocation for supercapacitor energy storage system in power grid primary frequency regulation | |
| Shazon et al. | Frequency response and its improvement using bess in a low inertia power system | |
| Spallarossa et al. | Underfrequency load shedding scheme for systems with large penetration renewable variable generation | |
| Coelho et al. | A test-bed for protection studies of synchronous generators and its interaction with the underexcitation and overexcitation limiters | |
| Trevisan et al. | Analysis of low frequency interactions between DFIG wind turbines and series compensated systems | |
| CN108649782B (en) | Parameter setting method and device of dynamic energy leakage device and simulation equipment | |
| Shazon et al. | Over-frequency mitigation using coordinated generator shedding scheme in a low inertia power system | |
| Nakas et al. | Investigation of the impact of load tap changers and automatic generation control on cascading events | |
| Saha et al. | Improving frequency response of a low inertia grid via an appropriate load shedding scheme | |
| Tirtashi et al. | Long-term voltage collapse analysis on a reduced order nordic system model |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |