CN108736444B - Phase modulator field loss protection method and system - Google Patents
Phase modulator field loss protection method and system Download PDFInfo
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- CN108736444B CN108736444B CN201810338072.5A CN201810338072A CN108736444B CN 108736444 B CN108736444 B CN 108736444B CN 201810338072 A CN201810338072 A CN 201810338072A CN 108736444 B CN108736444 B CN 108736444B
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
- H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
- H02H7/06—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric generators; for synchronous capacitors
- H02H7/065—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric generators; for synchronous capacitors against excitation faults
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Abstract
The invention discloses a phase modulator field loss protection method and system, and the methodThe method comprises the following steps: collecting and processing parameters of a phase modulator to obtain the loss-of-field protection parameters of the phase modulator; judgment confirmation UstWhether the voltage is within a first preset interval of the system voltage or not; if the U isstRespectively comparing E and U in a first preset interval of the system voltagerWith a predetermined threshold coefficient K, if E and UrWhen all the coefficients are smaller than the corresponding preset threshold coefficients K, the actions are protected; if said E and U arerIf any one of the threshold coefficients is not less than the corresponding preset threshold coefficient K, protection is returned; judging the UstWhether the voltage is within a second preset interval of the system voltage or not; if the U isstIn a second preset interval of the system voltage; judgment of E and UrWhether the judgment result meets a reverse criterion or a high-voltage criterion or not, and if the judgment result meets any one of the reverse criterion or the high-voltage criterion, protecting the action; if E and UrIf said reverse criterion and said high voltage criterion are not met, protection is returned.
Description
Technical Field
The invention relates to the technical field of electricity, in particular to a phase modulator magnetic loss protection method and system.
Background
In recent years, with the development of technologies such as direct current transmission, new energy, large power grids, extra-high voltage and the like and the application of a large number of power electronic equipment, the operation characteristics of power grids are greatly changed, the reactive power required by the system is increased day by day, the reactive power and voltage problems of the power grids need to be solved, and the reactive power compensation and regulation capacity needs to be enhanced. The synchronous phase modulator is a special reactive power source, can comprehensively improve the dynamic reactive power reserve of the system, can solve various voltage stability problems of insufficient dynamic reactive power of a receiving-end power grid, insufficient short-circuit capacity support of a weak transmitting-end power grid and the like, and enhances the voltage support and operation flexibility of the system. Compared with dynamic reactive power compensation devices based on power electronic technology, such as SVC (static var compensator), STATCOM (static synchronous compensator) and the like, the synchronous phase modulator not only provides short-circuit capacity for a system, but also has better reactive power output characteristic, and has unique advantages in reducing transient overvoltage of a direct current sending end, inhibiting commutation failure of a direct current receiving end, improving system stability by using forced excitation and the like.
When the synchronous phase modulator has a loss-of-field fault, the phase modulator does not send reactive power, but absorbs reactive power in a system, and voltage fluctuation of a power system is aggravated. If the loss of field fault is not detected and checked in time, when the direct current has phase change failure and the receiving-end power grid needs reactive support, the synchronous phase modulator absorbs the reactive power of the system because the loss of field fault still exists, further accelerates the voltage breakdown of the receiving-end power grid, and generates serious damage.
The current synchronous phase modulator is provided with two-section protection for field loss protection, wherein the protection I section is formed and logic by phase-entering reactive power and system low voltage, and the phase-entering reactive power is lower than a fixed value of the I section and the system voltage is lower than a fixed value of the voltage, so that an outlet is protected to act and the synchronous phase modulator is isolated; and the protection II section is formed by and logic of phase-entering reactive power and excitation low voltage, and the phase-entering reactive power is lower than the fixed value of the II section and the excitation voltage is lower than the fixed value, so that the outlet is protected to act and the synchronous phase modulator is isolated. However, when a loss-of-field fault occurs under the condition of high voltage of the system, the two-stage protection has a dead zone in a certain area. In order to reliably detect the loss-of-field fault of the isolated phase modulator and avoid the absorption of reactive power of the phase modulator due to the loss-of-field fault when the system needs reactive support, the loss-of-field protection of the phase modulator with high sensitivity must be configured.
Disclosure of Invention
In order to solve the problem that the existing protection mode of a phase modulator in the prior art has a dead zone in a certain area, the invention provides a phase modulator magnetic loss protection method and a phase modulator magnetic loss protection system, wherein the method and the system set criteria through regulating the internal potential of a stator and the excitation voltage of a rotor and judge whether the phase modulator is magnetic loss or not according to preset rules; the phase modulator loss-of-field protection method comprises the following steps:
collecting and processing parameters of a phase modulator to obtain the loss-of-field protection parameters of the phase modulator; the magnetic loss protection parameters comprise machine end parameters, excitation parameters and system parameters; the machine isThe end parameter comprises a per unit value E of an effective value of the potential in the stator of the phase modulator; the excitation parameter comprises per unit value U of excitation voltager(ii) a The system parameter comprises a per unit value U of an effective value of the system voltagest；
Judgment confirmation UstWhether the voltage is within a first preset interval of the system voltage or not;
if the U isstRespectively comparing E and U in a first preset interval of the system voltagerWith a predetermined threshold coefficient K, if E and UrWhen all the coefficients are smaller than the corresponding preset threshold coefficients K, the actions are protected;
if said E and U arerIf any one of the threshold coefficients is not less than the corresponding preset threshold coefficient K, the protection returns.
Further, the judgment confirms UstAfter the system voltage is within the first preset interval, the method further comprises the following steps:
judging the UstWhether the voltage is within a second preset interval of the system voltage or not;
if the U isstIn a second preset interval of the system voltage; judgment of E and UrWhether the judgment result meets a reverse criterion or a high-voltage criterion or not, and if the judgment result meets any one of the reverse criterion or the high-voltage criterion, protecting the action;
if E and UrIf the reverse criterion and the high-voltage criterion are not met, protection is returned;
further, the protection action comprises a delayed t protection action;
further, the first preset interval of the system voltage is 0-lambda1(ii) a The second preset interval of the system voltage is lambda1～λ2(ii) a Said lambda1Is a breakover voltage, λ2Is the maximum voltage of which 0<λ1<1、1<λ2<1.5; the value range of the preset threshold coefficient K is 0<K<1.2, presetting the threshold coefficient K according to the operation condition of a phase modulator before loss of magnetism;
further, the reverse criterion includes:
wherein C is an inverse coefficient, and C is more than or equal to 0 and less than or equal to 1; b is1For inverse shift coefficients, B1Is greater than 0; the high pressure criteria include:
wherein, B2Is a high voltage offset coefficient, B2＞0；
Further, the high pressure criteria further include rate start criteria, the rate start criteria including:
wherein, Delta t is a certain time interval,
terminal current before Δ t time interval, IeRated current for the generator end; n is1As a current start coefficient, 0<n1<1；Ur-ΔtAn excitation voltage before a delta t time interval; n is2For excitation voltage start-up factor, 0<n2<1；
The phase modifier magnetic loss protection system comprises:
the data acquisition unit is used for acquiring and processing parameters of the phase modulator to obtain the loss-of-field protection parameters of the phase modulator; the magnetic loss protection parameters comprise machine end parameters, excitation parameters and system parameters; the machine end parameter comprises a per unit value E of an effective value of the electric potential in the stator of the phase modulator; the excitation parameter comprises per unit value U of excitation voltager(ii) a The system parameter comprises a per unit value U of an effective value of the system voltagest；
A section judgment unit for judging the confirmation UstWhether the voltage is within a first preset interval of the system voltage or not;
a first interval criterion unit for comparing E and U, respectivelyrAnd the magnitude of a preset threshold coefficient K is compared with the magnitude of the preset threshold coefficient K, and the loss of excitation and the protection are output according to a criterion resultProtecting the instruction; if E and UrIf the output magnetic loss protection instructions are smaller than the corresponding preset threshold coefficients K, the output magnetic loss protection instructions are protection actions; if said E and U arerIf any one of the output loss of excitation protection instructions is not less than the corresponding preset threshold coefficient K, the output loss of excitation protection instruction is protection return;
further, the system comprises a second interval criterion unit;
the interval judgment unit is used for judging the UstWhether the voltage is within a second preset interval of the system voltage or not; if the U is judgedstStarting a second interval criterion unit within a second preset interval of the system voltage;
the second interval criterion unit is used for judging E and UrWhether the current transformer accords with a reverse criterion or a high-voltage criterion or not, and outputting a loss-of-magnetization protection instruction according to a criterion result; if the judgment result meets any one of the reverse criterion or the high-voltage criterion, the output loss-of-magnetization protection instruction is a protection action; if E and Ur do not accord with the reverse criterion and the high-voltage criterion, the output loss-of-magnetization protection instruction is protection return;
further, the protection action of the loss-of-magnetization protection instruction output by the first interval criterion unit comprises a protection action through time delay t; the protection action of the loss of excitation protection instruction output by the second interval criterion unit comprises a protection action after time delay t;
further, when the system voltage U is lower than the system voltage UstIn the interval 0-lambda1Then, the section judging unit judges the system unit UstIn a first preset interval; when the system voltage U isstIn the interval lambda1～λ2Then, the section judging unit judges the system unit UstIn a second preset interval; wherein 0<λ1<1、1<λ2<1.5；
Further, the reverse criterion includes:
wherein C is an inverse coefficient, and C is more than or equal to 0 and less than or equal to 1; b is1For inverse shift coefficients, B1Is greater than 0; the high pressure criteria include:
wherein, B2Is a high voltage offset coefficient, B2＞0；
Further, the high pressure criteria further include rate start criteria, the rate start criteria including:
wherein, Delta t is a certain time interval,
the terminal current before the time interval of delta t, Ie is the terminal rated current; n is1As a current start coefficient, 0<n1<1；Ur-ΔtAn excitation voltage before a delta t time interval; n is2For excitation voltage start-up factor, 0<n2<1。
The invention has the beneficial effects that: the technical scheme of the invention provides a phase modulator field loss protection method and system, wherein the method and system set criteria through adjusting the internal potential of a stator and the rotor excitation voltage and judge whether the phase modulator is field loss or not according to preset rules; the method and the system can reliably detect the loss-of-field fault of the isolation phase modulator, have no dead zone and high sensitivity, and solve the problem that the existing phase modulator protection has a certain zone dead zone when the system is in high voltage.
Drawings
A more complete understanding of exemplary embodiments of the present invention may be had by reference to the following drawings in which:
FIG. 1 is a flow chart of a phase modulator loss-of-field protection method according to an embodiment of the present invention;
FIG. 2 is a flow chart of a phase modulator loss-of-magnetization protection method according to various criteria implemented by a system voltage according to an embodiment of the present invention;
fig. 3 is a structural diagram of a phase modulator demagnetization protection system according to an embodiment of the present invention.
Detailed Description
The exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, however, the present invention may be embodied in many different forms and is not limited to the embodiments described herein, which are provided for complete and complete disclosure of the present invention and to fully convey the scope of the present invention to those skilled in the art. The terminology used in the exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, the same units/elements are denoted by the same reference numerals.
Unless otherwise defined, terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Further, it will be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense.
Fig. 1 is a flowchart of a phase modulator loss-of-field protection method according to an embodiment of the present invention, which sets criteria by adjusting an internal stator potential and a rotor excitation voltage and determines whether a phase modulator loses field according to preset rules; the phase modulator loss-of-field protection method comprises the following steps:
the acquisition and processing of the parameters mentioned in step 110 may be in real time, so that the system continuously obtains a set of phase modulator field loss protection parameters corresponding to time;
further, the magnetic loss protection parameters comprise machine end parameters, excitation parameters and system parameters; the machine end parameter comprises a per unit value E of an effective value of the electric potential in the stator of the phase modulator; the excitation parameter comprises per unit value U of excitation voltager(ii) a The system parameter comprises a per unit value U of an effective value of the system voltagest；
The terminal parameter also comprises terminal current;
further, the first preset interval of the system voltage is 0-lambda1(ii) a Said lambda1Is a breakover voltage of which 0<λ1<1；
Per unit value E of the effective value of the potential in the stator of the phase modulator and per unit value U of the excitation voltagerAll vary with the system voltage, when the system voltage UstUnder the breakover voltage, namely in the first preset interval, the per unit value E of the effective value of the potential in the stator of the phase modulator and the per unit value U of the excitation voltage at the momentrComparing the phase modulation with a preset threshold coefficient K to determine whether the phase modulator is in a loss-of-field state;
further, the value range of the preset threshold coefficient K is 0< K <1.2, and the threshold coefficient K is preset according to the operation condition of the phase modulation machine before magnetic loss;
further, the protection action comprises a delayed t protection action.
Further, as shown in fig. 2, fig. 2 is a flowchart of a phase modulator demagnetization protection method according to a system voltage, according to an embodiment of the present invention, for implementing multiple criteria; confirming U in the judgmentstAfter the system voltage is within the first preset interval, the method further comprises the following steps:
by regulating the breakover voltage lambda1Of the system voltage UstThe value range of (a) is divided into a first preset interval and a second preset interval, and the first preset interval is between 0 and the turning voltage as described above; the second predetermined interval is between the transition voltage and the maximum voltageTo (c) to (d); namely, the second preset interval of the system voltage is lambda1～λ2；λ2Is the maximum voltage of which 0<λ1<1、1<λ2<1.5；
further, the reverse criterion includes:
wherein C is an inverse coefficient, and C is more than or equal to 0 and less than or equal to 1; b is1For inverse shift coefficients, B1＞0；
further, the high pressure criteria include:
wherein, B2Is a high voltage offset coefficient, B2＞0；
A criterion for high-pressure regulation of the stator is set;
the criterion is the high pressure regulation criterion of the rotor;
further, the high pressure criteria may further include a rate start criterion, the rate start criterion being as follows:
wherein, Delta t is a certain time interval,
the terminal current before the time interval of delta t, Ie is the terminal rated current; n is1As a current start coefficient, 0<n1<1；Ur-ΔtAn excitation voltage before a delta t time interval; n is2For excitation voltage start-up factor, 0<n2<1；
In the normal regulation process of the system voltage, the rotor reverse regulation criterion, the stator reverse regulation criterion and the speed starting criterion are reliable and do not act, and the loss of field protection is reliable and does not act mistakenly.
When the camera has a demagnetization fault under the condition of high voltage of the system, the high voltage criterion of the stator, the high voltage criterion of the rotor and the speed starting criterion act, and the demagnetization protection acts reliably.
When the camera has a demagnetization fault under the condition of low voltage of the system, the stator reverse regulation criterion and the rotor reverse regulation criterion act, and the demagnetization protection acts reliably.
In conclusion, in the normal regulation process of the system voltage, the magnetic loss protection is reliable and does not act mistakenly, and when the camera has a magnetic loss fault under the condition of high voltage or low voltage of the system, the magnetic loss protection acts reliably, so that no dead zone exists, and the sensitivity is high.
Fig. 3 is a structural diagram of a phase modulator loss-of-magnetization protection system according to an embodiment of the present invention, and as shown in the drawing, the system includes:
the phase modulator comprises a data acquisition unit 301, wherein the data acquisition unit 301 is used for acquiring and processing phase modulator parameters to obtain phase modulator loss-of-magnetization protection parameters; the magnetic loss protection parameters comprise machine end parameters, excitation parameters and system parameters; the machine end parameter comprises a per unit value E of an effective value of the electric potential in the stator of the phase modulator; the excitation parameter comprises per unit value U of excitation voltager(ii) a The system parameter comprises a per unit value U of an effective value of the system voltagest；
A section judgment unit 302, the section judgment unit 302 being used for judging the confirmation UstWhether the voltage is within a first preset interval of the system voltage or not;
a first interval criterion unit 303, said first interval criterion unit 303 being configured to compare E and U, respectivelyrThe value of the threshold coefficient K is compared with a preset threshold coefficient K, and a loss of excitation protection instruction is output according to a criterion result; if E and UrIf the output magnetic loss protection instructions are smaller than the corresponding preset threshold coefficients K, the output magnetic loss protection instructions are protection actions; if said E and U arerIf any one of the output loss of excitation protection instructions is not less than the corresponding preset threshold coefficient K, the output loss of excitation protection instruction is protection return;
further, the system comprises a second interval criterion unit 304;
the section determining unit 302 is configured to determine the UstWhether the voltage is within a second preset interval of the system voltage or not; if the U is judgedstIn a second preset interval of the system voltage, starting a second interval criterion unit 304;
the second interval criterion unit 304 is used for judging E and UrWhether the current transformer accords with a reverse criterion or a high-voltage criterion or not, and outputting a loss-of-magnetization protection instruction according to a criterion result; if the judgment result meets any one of the reverse criterion or the high-voltage criterion, the output loss-of-magnetization protection instruction is a protection action; if E and UrIf the reverse criterion and the high-voltage criterion are not met, the output loss-of-magnetization protection instruction is a protection return;
further, the protection action of the loss-of-magnetization protection instruction output by the first interval criterion unit 303 includes a protection action by time delay t; the protection action of the loss-of-magnetization protection instruction output by the second interval criterion unit 304 includes a protection action through time delay t;
further, when the system voltage U is lower than the system voltage UstIn the interval 0-lambda1Then, the section determination unit 302 determines the system unit UstIn a first preset interval; when the system voltage U isstIn the interval lambda1～λ2Then, the section determination unit 302 determines the system unit UstIn a second preset interval; wherein 0<λ1<1、1<λ2<1.5；
Further, the reverse criterion includes:
wherein C is an inverse coefficient, and C is more than or equal to 0 and less than or equal to 1; b is1For inverse shift coefficients, B1Is greater than 0; the high pressure criteria include:
wherein, B2Is a high voltage offset coefficient, B2＞0；
Further, the high pressure criteria further include rate start criteria, the rate start criteria including:
wherein, Delta t is a certain time interval,
terminal current before Δ t time interval, IeRated current for the generator end; n is1As a current start coefficient, 0<n1<1；Ur-ΔtAn excitation voltage before a delta t time interval; n is2For excitation voltage start-up factor, 0<n2<1。
In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the disclosure may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.
Those skilled in the art will appreciate that the modules in the device in an embodiment may be adaptively changed and disposed in one or more devices different from the embodiment. The modules or units or components of the embodiments may be combined into one module or unit or component, and furthermore they may be divided into a plurality of sub-modules or sub-units or sub-components. All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or elements of any method or apparatus so disclosed, may be combined in any combination, except combinations where at least some of such features and/or processes or elements are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Reference to step numbers in this specification is only for distinguishing between steps and is not intended to limit the temporal or logical relationship between steps, which includes all possible scenarios unless the context clearly dictates otherwise.
Moreover, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the disclosure and form different embodiments. For example, any of the embodiments claimed in the claims can be used in any combination.
Various component embodiments of the disclosure may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. The present disclosure may also be embodied as device or system programs (e.g., computer programs and computer program products) for performing a portion or all of the methods described herein. Such programs implementing the present disclosure may be stored on a computer-readable medium or may be in the form of one or more signals. Such a signal may be downloaded from an internet website or provided on a carrier signal or in any other form.
It should be noted that the above-mentioned embodiments illustrate rather than limit the disclosure, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The disclosure may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several systems, several of these systems may be embodied by one and the same item of hardware.
The foregoing is directed to embodiments of the present disclosure, and it is noted that numerous improvements, modifications, and variations may be made by those skilled in the art without departing from the spirit of the disclosure, and that such improvements, modifications, and variations are considered to be within the scope of the present disclosure.
Claims (12)
1. A phase modulator loss-of-field protection method comprises the following steps:
collecting and processing parameters of a phase modulator to obtain the loss-of-field protection parameters of the phase modulator; the magnetic loss protection parameters comprise machine end parameters, excitation parameters and system parameters; the machine end parameter comprises a per unit value E of an effective value of the electric potential in the stator of the phase modulator; the excitation parameter comprises a per unit value Ur of the excitation voltage; the system parameter comprises a per unit value Ust of the effective value of the system voltage;
judging and confirming whether the Ust is in a first preset interval of the system voltage, wherein the first preset interval of the system voltage is 0-lambda1，λ1Is a breakover voltage;
if the Ust is in a first preset interval of the system voltage, respectively comparing the E and the Ur with a preset threshold coefficient K, and if the E and the Ur are both smaller than the corresponding preset threshold coefficient K, protecting the action, wherein the preset threshold coefficient K is preset according to the operating condition of the phase modulator before loss of magnetism;
and if any one of the E and the Ur is not less than the corresponding preset threshold coefficient K, returning the protection.
2. The method of claim 1, wherein after said determining determines whether Ust is within a first predetermined interval of a system voltage, the method further comprises:
judging whether the use is in a second preset interval of the system voltage;
if the Ust is in a second preset interval of the system voltage; judging whether E and Ur meet a reverse criterion or a high-voltage criterion, and protecting the action if the E and the Ur meet any one of the reverse criterion or the high-voltage criterion;
if E and Ur do not meet the reverse criterion and the high voltage criterion, protection is returned.
3. The method according to claim 1 or 2, characterized in that: the protection action comprises a delayed t protection action.
4. The method of claim 2, wherein: the second preset interval of the system voltage is lambda1～λ2；λ2Is the maximum voltage of which 0<λ1<1、1<λ2<1.5；
The value range of the preset threshold coefficient K is 0< K < 1.2.
5. The method of claim 4, wherein:
the reverse criteria include:
wherein C is an inverse coefficient, and C is more than or equal to 0 and less than or equal to 1; b is1For inverse shift coefficients, B1＞ 0 ；
The high pressure criteria include:
wherein, B2Is a high voltage offset coefficient, B2＞0。
6. The method of claim 5, wherein the high pressure criteria further comprises a rate start criteria, the rate start criteria comprising:
wherein, Delta t is a certain time interval,İ - tΔterminal current before Δ t time interval, IeRated current for the generator end; n is1As a current start coefficient, 0<n1<1；U r- tΔAn excitation voltage before a delta t time interval; n is2For excitation voltage start-up factor, 0<n2<1。
7. A phase modifier loss of field protection system, the system comprising:
the data acquisition unit is used for acquiring and processing parameters of the phase modulator to obtain the loss-of-field protection parameters of the phase modulator; the magnetic loss protection parameters comprise machine end parameters, excitation parameters and system parameters; the machine end parameter comprises a per unit value E of an effective value of the electric potential in the stator of the phase modulator; the excitation parameter comprises a per unit value Ur of the excitation voltage; the system parameter comprises a per unit value Ust of the effective value of the system voltage;
an interval judgment unit for judging whether the confirmation Ust is within a first preset interval of the system voltage, wherein the first preset interval of the system voltage is 0-lambda1，λ1Is a breakover voltage;
the first interval criterion unit is used for respectively comparing the E and the Ur with a preset threshold coefficient K and outputting a demagnetization protection instruction according to a criterion result; if both E and Ur are smaller than the corresponding preset threshold coefficient K, the output loss-of-magnetization protection instruction is a protection action; and if any one of the E and the Ur is not less than the corresponding preset threshold coefficient K, the output loss-of-magnetization protection instruction is protection return, wherein the preset threshold coefficient K is preset according to the running condition of the phase modulator before loss-of-magnetization.
8. The system of claim 7, wherein: the system comprises a second interval criterion unit;
the interval judgment unit is used for judging whether the Ust is in a second preset interval of the system voltage; if the Ust is judged to be in a second preset interval of the system voltage, a second interval criterion unit is started;
the second interval criterion unit is used for judging whether the E and the Ur accord with a reverse criterion or a high-voltage criterion or not and outputting a loss-of-magnetization protection instruction according to a criterion result; if the judgment result meets any one of the reverse criterion or the high-voltage criterion, the output loss-of-magnetization protection instruction is a protection action; and if the E and the Ur do not accord with the reverse criterion and the high-voltage criterion, the output loss-of-magnetization protection instruction is protection return.
9. The system of claim 8, wherein: the protection action of the loss of excitation protection instruction output by the first interval criterion unit comprises a protection action through time delay t; and the protection action of the loss of excitation protection instruction output by the second interval criterion unit comprises protection action through time delay t.
10. The system of claim 8, wherein: when the system voltage Ust is in the interval lambda1～λ2Then, the interval judgment unit judges that the system voltage Ust is in a second preset interval; wherein 0<λ1<1、1<λ2<1.5。
11. The system of claim 10, wherein:
the reverse criteria include:
wherein C is an inverse coefficient, and C is more than or equal to 0 and less than or equal to 1; b is1For inverse shift coefficients, B1＞ 0 ；
The high pressure criteria include:
wherein, B2Is a high voltage offset coefficient, B2＞0。
12. The system of claim 11 wherein said high pressure criteria further comprises a rate start criteria, said rate start criteria comprising:
wherein, Delta t is a certain time interval,İ - tΔterminal current before Δ t time interval, IeRated current for the generator end; n is1As a current start coefficient, 0<n1<1；U r- tΔAn excitation voltage before a delta t time interval; n is2For excitation voltage start-up factor, 0<n2<1。
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| CN109038494B (en) * | 2018-08-16 | 2019-10-22 | 国电南瑞科技股份有限公司 | Phase modifier field loss protection excitation low-voltage judgment method |
| CN110061475B (en) * | 2019-03-22 | 2022-10-11 | 中国电力科学研究院有限公司 | Phase modulator loss-of-field protection method and system based on influence degree on system |
| CN112444745A (en) * | 2019-09-03 | 2021-03-05 | 南京南瑞继保工程技术有限公司 | Method and device for judging phase modulator field loss fault caused by pulse loss |
| CN110994535B (en) * | 2019-11-08 | 2022-07-29 | 国电南瑞科技股份有限公司 | Method and system for judging disconnection of excitation voltage measurement circuit |
| CN111509668B (en) * | 2020-04-23 | 2022-06-28 | 南京南瑞继保电气有限公司 | Phase modulator loss-of-field protection method and device and electronic equipment |
| CN112290509B (en) * | 2020-09-16 | 2024-03-08 | 中国电力科学研究院有限公司 | Phase modulation loss magnetic protection method and system for preventing misoperation caused by voltage fluctuation |
| CN112952756B (en) * | 2021-03-04 | 2023-10-20 | 中国电力科学研究院有限公司 | Fixed value self-adaptive adjustment type loss-of-excitation protection method for camera |
| CN116780471B (en) * | 2023-08-24 | 2023-11-24 | 南方电网调峰调频发电有限公司 | Direct-current voltage-based symmetric loss-of-excitation protection method for variable-speed pumping and storage unit network side |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001037074A (en) * | 1999-07-16 | 2001-02-09 | Toshiba Corp | Generator field loss protector |
| CN101588153A (en) * | 2009-07-08 | 2009-11-25 | 浙江省电力公司 | Method of limiting low excitation |
| CN103454585A (en) * | 2013-08-27 | 2013-12-18 | 河海大学 | Permanent magnet synchronous motor field failure diagnosis method based on residual voltage after ac dump |
| WO2014117279A1 (en) * | 2013-02-04 | 2014-08-07 | University Of Saskatchewan | Methods and apparatus for detection of generator faults |
| CN104283191A (en) * | 2014-10-16 | 2015-01-14 | 华北电力大学 | Method and device for field loss protection of electric generator |
| CN107658847A (en) * | 2017-10-20 | 2018-02-02 | 国家电网公司华中分部 | The low fiting tuning method for encouraging limitation and field loss protection based on power planes |
| CN107689622A (en) * | 2017-10-11 | 2018-02-13 | 安徽新力电业科技咨询有限责任公司 | Relate to the generation of field loss protection acting characteristic curve and the check method of net definite value check |
-
2018
- 2018-04-16 CN CN201810338072.5A patent/CN108736444B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001037074A (en) * | 1999-07-16 | 2001-02-09 | Toshiba Corp | Generator field loss protector |
| CN101588153A (en) * | 2009-07-08 | 2009-11-25 | 浙江省电力公司 | Method of limiting low excitation |
| WO2014117279A1 (en) * | 2013-02-04 | 2014-08-07 | University Of Saskatchewan | Methods and apparatus for detection of generator faults |
| CN103454585A (en) * | 2013-08-27 | 2013-12-18 | 河海大学 | Permanent magnet synchronous motor field failure diagnosis method based on residual voltage after ac dump |
| CN104283191A (en) * | 2014-10-16 | 2015-01-14 | 华北电力大学 | Method and device for field loss protection of electric generator |
| CN107689622A (en) * | 2017-10-11 | 2018-02-13 | 安徽新力电业科技咨询有限责任公司 | Relate to the generation of field loss protection acting characteristic curve and the check method of net definite value check |
| CN107658847A (en) * | 2017-10-20 | 2018-02-02 | 国家电网公司华中分部 | The low fiting tuning method for encouraging limitation and field loss protection based on power planes |
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