CN102570470A - Transient stability-based generator phase advancing depth determination method - Google Patents

Transient stability-based generator phase advancing depth determination method Download PDF

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CN102570470A
CN102570470A CN2012100331698A CN201210033169A CN102570470A CN 102570470 A CN102570470 A CN 102570470A CN 2012100331698 A CN2012100331698 A CN 2012100331698A CN 201210033169 A CN201210033169 A CN 201210033169A CN 102570470 A CN102570470 A CN 102570470A
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generator
angle
disturbance
power
depth
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CN102570470B (en
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蒋宇
胡鹤轩
张晔
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Hohai University HHU
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Abstract

The invention discloses a transient stability-based generator phase advancing depth determination method, and belongs to a calculation method for maximum phase advancing depth under the condition of transient stability of a turbine generator. The method comprises the following steps of: during a transient process of the turbine generator, calculating an accelerating area and a slow-down area swept by a rotor power angle through integration by using a difference value between mechanical power and electromagnetic power of the generator; and finally determining the limit phase advancing depth of the generator under the condition of transient stability by using the property that the accelerating area is equal to the slow-down area. According to the transient stability-based generator phase advancing depth determination method, the conventional phase advancing depth determination method which is conservative can be changed, and the phase advancing depth of the turbine generator can be increased on the premise of not influencing the safety, so that more reactive power compensation capacity is economically achieved.

Description

Advance the phase degree of depth based on the generator of transient stability and confirm method
Technical field
The present invention relates to a kind of generator and advance the phase degree of depth and confirm method, belong to the computational methods that maximum under the turbo generator transient stability is advanced the phase degree of depth based on transient stability.
Background technology
The leading phase operation mode of generator is owing to the too high quality of power supply that influences of system voltage, and a kind of reactive voltage control method of taking.Adopt the purpose of technology mutually; Be under the prerequisite that does not increase huge investment; Lean on a large amount of absorption system reactive powers of generator; Thereby reach the effect that reduces system voltage, " the current domestic meaning of leading phase operation and the problem of existence of carrying out " (Chen Qun, etc. big motor technology .2000 (2): 14-18) etc. a series of documents have been done argumentation to this.In addition, " unit through leading phase operation test can need leading phase operation by electrical network to " Jiangsu electrical network tracking electricity power enterprise evaluation method " the 31 regulation, rewards 10,000 yuan at every turn.", " compensate during according to 15 yuan/megavar behind " No. 113, Jiangsu electrical network tracking generating set auxiliary management implementing method (the electric prison valency (2011) of reviving) " the 15 regulation generating set leading phase operation.", so the generator leading phase operation can produce huge direct economic benefit to the power plant.From " high-rating generator advances phase safe operation analysis of finite element method " (all fish hawks; Hu Minqiang. the journal .1995 of Southeast China University; The 83-90 page or leaf) etc. 25 (4): the achievement in research of a series of documents can be found out; Confirm the size (maximum is advanced the phase degree of depth) of generator leading phase operation ability in the engineering; The main limits value of considering steady stability limits value, generator machine end heating in winding limits value and the generator unit stator winding overcurrent of generator's power and angle lacks the restrictive condition of taking into account generator transient stability (generating prow pendulum is stable).Because electric power system is a dynamical system that constantly has disturbance to take place; Therefore when definite generator maximum is advanced the phase degree of depth; The transient stability constraints of considering generator is necessary, and this " power system security guide rule (DL/T 755-2001) " the 4th chapter and appendix A 2.2, A3 money have been done regulation and explanation.
Summary of the invention
The present invention proposes a kind of generator based on transient stability (generating prow pendulum stable) advances the phase degree of depth and confirms method; Remedied that existing unstability, single transient stability extreme value are not that the generator of restrictive condition advances the phase degree of depth and confirms method with generator static state; Perfect generator maximum is advanced the computational methods system of the phase degree of depth; Not only can also bring enormous profits for electricity power enterprise for power grid enterprises practice thrift huge reactive apparatus capital fund.
The present invention adopts following technical scheme for solving its technical problem:
A kind of generator based on transient stability advances the phase degree of depth and confirms method, confirms that through the first pendulum stability of analyzing generator's power and angle under the disturbance generator advances the degree of depth limit value of phase, comprises the steps:
1) according under the generator leading phase operation operating mode, disturbed back generator amature electromagnetism-mechanical output is the physical process of balance again, sets up Mathematical Modeling and does
Figure 232529DEST_PATH_IMAGE001
formula 3
According to relation between formula 3 described each physical quantity and preset generator's power and angle steady stability limit value
Figure 783596DEST_PATH_IMAGE002
(known quantity); Under generator amature disturbance post acceleration area and constraints that retardation area equates; Utilize numerical computation method; Like Newton interpolating method, Lagrange's interpolation, Hermite interpolation method, piecewise low-order interpolation method, spline method, solve the maximum work angle that the preceding generator leading phase operation state of disturbance allows down;
2) according to turbo generator leading phase operation vector constraints:
Figure 870424DEST_PATH_IMAGE004
formula 1
And the maximum work angle
Figure 97006DEST_PATH_IMAGE003
that allows under the generator leading phase operation state that step 1) solved, find the solution and draw system impedance angle
Figure 338632DEST_PATH_IMAGE005
;
3) advance phase degree of depth expression formula according to turbo generator:
Figure 941651DEST_PATH_IMAGE006
formula 2
And step 2) the system impedance angle that solves
Figure 381860DEST_PATH_IMAGE005
calculates the maximum of describing under the generator transient stability and advances phase degree of depth Q;
Wherein:
Figure 982606DEST_PATH_IMAGE007
is the unloaded electromotive force of generator;
Figure 9730DEST_PATH_IMAGE008
is Infinite bus system voltage;
Figure 478757DEST_PATH_IMAGE009
is the generator unit stator electric current;
Figure 39051DEST_PATH_IMAGE010
is the synchronous reactance of generator; is generator operation merit angle, and
Figure 384506DEST_PATH_IMAGE005
is the system impedance angle; T is the mechanical output of prime mover, the reactive power that the Q generator sends, and promptly maximum is advanced the phase degree of depth;
Figure 267011DEST_PATH_IMAGE012
is the maximum electrical magnetic power of generator before disturbance takes place;
Figure 681812DEST_PATH_IMAGE013
is the maximum electrical magnetic power of disturbance excision back generator;
Figure 421098DEST_PATH_IMAGE003
is the maximum work angle that allows under the generator leading phase operation state;
Figure 485131DEST_PATH_IMAGE014
is the balance merit angle after the generator disturbance excision;
Figure 233644DEST_PATH_IMAGE015
is the maximum work angle of arranging after the generator disturbance; is the generator's power and angle steady stability limit value of presetting;
Figure 239570DEST_PATH_IMAGE016
is the interconnection reactance before the disturbance,
Figure 227118DEST_PATH_IMAGE017
be the interconnection reactance after the disturbance excision.
Beneficial effect of the present invention is following:
The present invention has remedied existing only with generator static state not unstability, single transient stability extreme value, confirms method system for the generator of restrictive condition advances the phase degree of depth; Perfect generator maximum is advanced the computational methods system of the phase degree of depth, and it is more accurate to make turbo generator advance the result of calculation of the phase degree of depth.The present invention can improve the phase degree of depth of advancing that routine is tending towards guarding and confirm method, can be under the prerequisite that does not influence fail safe, and that improves turbo generator advances the phase degree of depth, thus the economic more reactive power compensation capacity of acquisition.
Description of drawings
Fig. 1 is a generator leading phase operation vectogram.
Fig. 2 is generator operation (advancing phase) state diagram before the disturbance.
Fig. 3 is the instantaneous generator vectogram of external disturbance.
Fig. 4 is generating prow pendulum running orbit figure behind the external disturbance.
Fig. 5 is generating prow pendulum running orbit-acceleration-deceleration area contact figure behind the external disturbance.
Embodiment
Below in conjunction with accompanying drawing the invention is explained further details.
At first the correlation between each electric parameters of generator after advancing is mutually analyzed, conclusion is as shown in Figure 1.Wherein
Figure 688951DEST_PATH_IMAGE007
is the unloaded electromotive force of generator;
Figure 835899DEST_PATH_IMAGE008
is generator terminal voltage;
Figure 926214DEST_PATH_IMAGE009
is the generator unit stator electric current;
Figure 170114DEST_PATH_IMAGE020
is total reactance;
Figure 625366DEST_PATH_IMAGE011
is generator operation merit angle, and
Figure 587506DEST_PATH_IMAGE005
is the system impedance angle.Through the equal dot product in three limits
Figure 714468DEST_PATH_IMAGE021
with vector triangle among Fig. 1; Obtain
Figure 750558DEST_PATH_IMAGE022
=
Figure 439028DEST_PATH_IMAGE023
=
Figure 622885DEST_PATH_IMAGE024
, characterize electromagnetic power; =
Figure 211178DEST_PATH_IMAGE026
=
Figure 572014DEST_PATH_IMAGE027
characterizes the absorbable maximum reactive capability when being zero of gaining merit.
Next sets up the state model under the generator leading phase operation steady working condition, and conclusion is as shown in Figure 2.A wherein 0The nominal operation state point of some representative generator, A 1Point is the initialization state point of generator behind the leading phase operation, and T is the mechanical output of prime mover, P 1Be the active power of generator output,
Figure 243167DEST_PATH_IMAGE011
=90 ° is the steady state stability limit value of generator operation,
Figure 151080DEST_PATH_IMAGE002
It is the generator's power and angle steady stability limit value of presetting.
Set up disturbed instantaneous electric parameters variation model behind the generator leading phase operation once more, conclusion is as shown in Figure 3.Wherein the duty point of back generator takes place in the A2 point for disturbance.
Set up once more that the head under the disturbance puts process model behind the generator leading phase operation, conclusion is as shown in Figure 4.Wherein, The A2 point is the initial launch point of generator after the disturbance; is corresponding system impedance angle, be corresponding generator's power and angle; The A3 point is the new balance movement point of exterior mechanical power after the disturbance and electromagnetic power, and
Figure 350483DEST_PATH_IMAGE030
,
Figure 622939DEST_PATH_IMAGE031
are corresponding system impedance angle, merit angle; The A4 point is the maximum operating point in generator amature angle under the effect of inertia after the disturbance, and
Figure 816023DEST_PATH_IMAGE032
,
Figure 954881DEST_PATH_IMAGE033
are corresponding system impedance angle, merit angle.
Set up at last according to above-mentioned each submodel, the generating prow pendulum running orbit-acceleration-deceleration area model under the disturbance that comprehensively obtains, as shown in Figure 5.C wherein 1, C 2, C 3, C 4The point in power integration coordinate system (left side) with P-Q coordinate system (right side) in A 1, A 2, A 3, A 4Point is corresponding respectively.
Under generator leading phase operation operating mode shown in Figure 5, disturbed back generator amature electromagnetism-mechanical output is the physical process model of balance again, sets up Mathematical Modeling and does
Figure 335046DEST_PATH_IMAGE001
formula 3
According to the relation between formula 3 described each known physical amount (
Figure 912658DEST_PATH_IMAGE007
,
Figure 897932DEST_PATH_IMAGE008
,
Figure 771472DEST_PATH_IMAGE034
,
Figure 638934DEST_PATH_IMAGE016
,
Figure 692341DEST_PATH_IMAGE035
, T), and known generator's power and angle steady stability pre-set limit ; Under generator amature disturbance post acceleration area and constraints that retardation area equates, utilize numerical computation method (like Newton interpolating method, Lagrange's interpolation, Hermite interpolation method, piecewise low-order interpolation method, spline method) to solve the maximum work angle that allows under the generator leading phase operation state.
According to formula 1
And the maximum work angle that allows under the generator leading phase operation state that is solved, find the solution and draw system impedance angle
Figure 932305DEST_PATH_IMAGE005
.
According to
Figure 646183DEST_PATH_IMAGE006
formula 2
And system impedance angle
Figure 989702DEST_PATH_IMAGE005
, calculate and describe the reactive power Q that the generator maximum is advanced the phase degree of depth.
Wherein:
Figure 447228DEST_PATH_IMAGE007
is the unloaded electromotive force of generator;
Figure 323917DEST_PATH_IMAGE008
is Infinite bus system voltage; is the generator unit stator electric current;
Figure 60019DEST_PATH_IMAGE010
is the synchronous reactance of generator;
Figure 321236DEST_PATH_IMAGE011
is generator operation merit angle, and
Figure 990115DEST_PATH_IMAGE005
is the system impedance angle; T is the mechanical output of prime mover, the reactive power that the Q generator sends, and promptly maximum is advanced the phase degree of depth;
Figure 45796DEST_PATH_IMAGE012
is the maximum electrical magnetic power of generator before disturbance takes place;
Figure 862442DEST_PATH_IMAGE013
is the maximum electrical magnetic power of disturbance excision back generator; is the maximum work angle that allows under the generator leading phase operation state;
Figure 76834DEST_PATH_IMAGE014
is the balance merit angle after the generator disturbance excision;
Figure 303416DEST_PATH_IMAGE015
is the maximum work angle of arranging after the generator disturbance;
Figure 105893DEST_PATH_IMAGE002
is the generator's power and angle steady stability limit value of presetting; is the interconnection reactance before the disturbance,
Figure 149121DEST_PATH_IMAGE017
be the interconnection reactance after the disturbance excision.

Claims (1)

1. the generator based on transient stability advances the phase degree of depth and confirms method, it is characterized in that confirming that through the first pendulum stability of analyzing generator's power and angle under the disturbance generator advances the degree of depth limit value of phase, comprises the steps:
1) according under the generator leading phase operation operating mode, disturbed back generator amature electromagnetism-mechanical output is the physical process of balance again, sets up Mathematical Modeling and does
formula 3
According to relation between formula 3 described each physical quantity and preset generator's power and angle steady stability limit value
Figure 783259DEST_PATH_IMAGE002
; Under generator amature disturbance post acceleration area and constraints that retardation area equates, utilize numerical computation method to solve the maximum work angle
Figure 984433DEST_PATH_IMAGE003
that allows under the generator leading phase operation state;
2) according to turbo generator leading phase operation vector constraints:
formula 1
And the maximum work angle
Figure 879894DEST_PATH_IMAGE003
that allows under the generator leading phase operation state that step 1) solved, find the solution and draw system impedance angle
Figure 927484DEST_PATH_IMAGE005
;
3) advance phase degree of depth expression formula according to turbo generator:
formula 2
And step 2) the system impedance angle that solves
Figure 931136DEST_PATH_IMAGE005
calculates the maximum of describing under the generator transient stability and advances phase degree of depth Q;
Wherein:
Figure 984543DEST_PATH_IMAGE007
is the unloaded electromotive force of generator;
Figure 886640DEST_PATH_IMAGE008
is Infinite bus system voltage;
Figure 429616DEST_PATH_IMAGE009
is the generator unit stator electric current;
Figure 722057DEST_PATH_IMAGE010
is the synchronous reactance of generator;
Figure 142937DEST_PATH_IMAGE011
is generator operation merit angle, and
Figure 837223DEST_PATH_IMAGE005
is the system impedance angle; T is the mechanical output of prime mover, the reactive power that the Q generator sends, and promptly maximum is advanced the phase degree of depth;
Figure 551101DEST_PATH_IMAGE012
is the maximum electrical magnetic power of generator before disturbance takes place;
Figure 658735DEST_PATH_IMAGE013
is the maximum electrical magnetic power of disturbance excision back generator;
Figure 53944DEST_PATH_IMAGE003
is the maximum work angle that allows under the generator leading phase operation state;
Figure 665054DEST_PATH_IMAGE014
is the balance merit angle after the generator disturbance excision;
Figure 753096DEST_PATH_IMAGE015
is the maximum work angle of arranging after the generator disturbance;
Figure 580981DEST_PATH_IMAGE002
is the generator's power and angle steady stability limit value of presetting;
Figure 576619DEST_PATH_IMAGE016
is the interconnection reactance before the disturbance, be the interconnection reactance after the disturbance excision.
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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014117582A1 (en) * 2013-02-04 2014-08-07 国家电网公司 Real-time emergency control method of relative kinetic energy-based power system transient stability
CN105375487A (en) * 2015-12-11 2016-03-02 东南大学 Modeling method for phase advance capability of generator set
CN106099979A (en) * 2016-07-19 2016-11-09 国网河北省电力公司电力科学研究院 A kind of unit under-excitation ability considering that the stabilization of power grids limits analyzes method
CN112910008A (en) * 2021-01-11 2021-06-04 中国电力科学研究院有限公司 Method for optimizing phase advance depth of synchronous unit and preventing high voltage from occurring
CN113484575A (en) * 2021-07-23 2021-10-08 国网重庆市电力公司电力科学研究院 Power angle search-based generator phase advance capability pre-evaluation method, equipment and medium

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CN101588072A (en) * 2008-01-11 2009-11-25 北京博旺天成科技发展有限公司 Novel energy-saving power regulator

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CN101588072A (en) * 2008-01-11 2009-11-25 北京博旺天成科技发展有限公司 Novel energy-saving power regulator

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014117582A1 (en) * 2013-02-04 2014-08-07 国家电网公司 Real-time emergency control method of relative kinetic energy-based power system transient stability
CN105375487A (en) * 2015-12-11 2016-03-02 东南大学 Modeling method for phase advance capability of generator set
CN105375487B (en) * 2015-12-11 2018-01-12 东南大学 A kind of modeling method of generating set under-excitation ability
CN106099979A (en) * 2016-07-19 2016-11-09 国网河北省电力公司电力科学研究院 A kind of unit under-excitation ability considering that the stabilization of power grids limits analyzes method
CN112910008A (en) * 2021-01-11 2021-06-04 中国电力科学研究院有限公司 Method for optimizing phase advance depth of synchronous unit and preventing high voltage from occurring
CN112910008B (en) * 2021-01-11 2023-08-25 中国电力科学研究院有限公司 Method for optimizing phase advance depth of synchronous unit to prevent high voltage
CN113484575A (en) * 2021-07-23 2021-10-08 国网重庆市电力公司电力科学研究院 Power angle search-based generator phase advance capability pre-evaluation method, equipment and medium

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