CN108023362A - The computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure - Google Patents
The computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure Download PDFInfo
- Publication number
- CN108023362A CN108023362A CN201711448501.6A CN201711448501A CN108023362A CN 108023362 A CN108023362 A CN 108023362A CN 201711448501 A CN201711448501 A CN 201711448501A CN 108023362 A CN108023362 A CN 108023362A
- Authority
- CN
- China
- Prior art keywords
- stability
- region
- cluster system
- failure
- time constant
- 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.)
- Pending
Links
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
- H02J3/36—Arrangements for transfer of electric power between ac networks via a high-tension dc link
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/08—Locating faults in cables, transmission lines, or networks
- G01R31/088—Aspects of digital computing
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/60—Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Power Engineering (AREA)
- Mathematical Physics (AREA)
- Theoretical Computer Science (AREA)
- General Physics & Mathematics (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Abstract
The invention discloses a kind of computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure, the computational methods comprise the following steps：Receiving end power grid will be sent to be reduced to two cluster system, and two cluster system are expanded into three cluster system, i.e. including three regions；Generator rotor angle when determining that the receiving end electric network fault of three cluster system is cut off by runge kutta method is poor, calculates according to generator rotor angle difference and maximum excision angle and accelerates area and retardation area, and then determines stability margin；The method further includes：Inertia time constant, the duration of failure and the relation of stability margin are analyzed, obtains influence of the duration of inertia time constant, failure to system stability.Two cluster system are expanded to three actual cluster system by the present invention, are determined critical clearing angle using runge kutta method, are calculated the stability margin of electric system, meet a variety of needs in practical application.
Description
Technical field
Transient stability the present invention relates to system after electrical engineering field, more particularly to a kind of multiple-circuit line commutation failure is commented
The computational methods of valency index.
Background technology
In recent years, quickly increased in the North China Power Telecommunication Network and Northwest Grid in China, wind-powered electricity generation, photovoltaic installed capacity, make China by
Step promotes transferring electricity from the west to the east, builds a plurality of UHVDC Transmission Lines, and by the end of the year 2015, southwestern power grid shares brocade Soviet Union, guest's gold, gives again
3 times ± 800kV extra-high voltage direct-currents to load center East China Power Grid power transmission, Central China Power Grid share 4 times ± 500kV superhigh voltage DCs to
Load center East China Power Grid power transmission, the general power of 7 times direct currents reach 31760MW[1].According to China's Electric Power Network Planning, will also in recent years
Put into operation the more times extra-high voltage direct-currents such as Shanxi North-south capital, Xi Meng-Taizhou, Ling Zhou-Shaoxing, quasi- east-Wan Nan[2-3].Extra-high voltage direct-current transmits
Being continuously increased for capacity and transmission range, gradually forms the power grid characteristic of " tetanic weak friendship ", direct current is sent between receiving end AC system
Coupling and influencing each other gradually highlight.The advantage (buffer action) during extra-high voltage direct-current is built under initial stage " handing over by force weak straight "
Progressively disappear, send the asynchronous interconnected network of receiving end on the contrary using direct current as medium, event is realized by the dc power response after failure
Barrier transmits[4]。
Receiving-end system failure trigger multiple-circuit line at the same time commutation failure cause sending stability disruption be using direct current as
Medium carries out the typical case of failure transmission.At present, the research for this failure mode is broadly divided into two group of planes methods and three group of planes
Method[5-7]：Two group of planes methods are that the real system being analysed to is equivalent to two cluster system to carry out stable mechanism and influence factor point
Analysis, can be equivalent to two cluster system by real system by law of equal areas and trigger stability to destroy to analyze direct-current commutation failure
Stable mechanism[5], stable mechanism can be intuitively analyzed from physical essence, but difficult, second order is realized in the quantitative calculating of complication system
Linear system shock response model is easy to quantitative calculating[6], but the adaptation for stablizing essence and interconnection high power situation can not be annotated
Property is poor；In order to describe the complex state of actual sending, " three China " system is equivalent to three cluster system[7], can preferably annotate
The stable mechanism that receiving-end system failure causes sending stability to be destroyed is released, but the existing document on three cluster system stresses
In the mechanism that analysis stability is destroyed, and be still not perfect in terms of quantitative assessing index calculating, can not quantitative evaluation index,
Therefore still needed in terms of quantitative calculating further perfect.
Bibliography
[1] Wang Chunming, influence [J] the electric power network techniques of Liu Bing's regional internet multiple-circuit line commutation failures to sending,
2013,37 (4)：1052-1057.
[2] Guo Xiaojiang, Shao Yao, Zhou Qinyong, wait multi-infeed HVDC area power grid safety and stability Journal of Sex Research [R] Beijing：In
Electric Power Research Institute of state, 2010.
[3] Shao Yao, Tang Yong, Guo Xiaojiang, waits .2015 extra-high voltages planning power grid North China and East China multi-infeed HVDC defeated
Commutation failure analysis [J] electric power network techniques of electric system, 2011,35 (10)：9-15.
[4] Li Ming saves the extensive extra-high voltage alternating current-direct current serial-parallel power grid specificity analysises of and operation control [J] electric power network techniques,
2016,40 (4)：985-991.
[5] Tu Jingzhe, Zhang Jian, Wang Jianming, wait the asynchronous interacted system receiving end failure of large-scale direct currents to trigger sending end to stablize broken
Bad Analysis on Mechanism [J] Proceedings of the CSEEs, 2015,35 (21)：5492-5499.
[6] He Jian, Zhang Jian, Guo Qiang, wait two regional exchange interconnection tie power fluctuation peaks under the impact of direct-current commutation failures
Calculate [J] Proceedings of the CSEEs, 2015,35 (4)：804-810.
[7] Tu Jingzhe, Zhang Jian, Jia Junchuan, wait three cluster system stable mechanism of sending end and shadow after multiple-circuit line commutation failures
Ring Elements research [J] electric power network techniques, 2017,41 (03)：683-691.
The content of the invention
The present invention provides a kind of computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure, sheet
Two machine systems are expanded to three actual cluster system by invention, are determined critical clearing angle using runge kutta method, are calculated power train
The stability margin of system, it is described below：
The computational methods of the transient stability evaluation index of system after a kind of multiple-circuit line commutation failure, the computational methods bag
Include following steps：
Receiving end power grid will be sent to be reduced to two cluster system, and two cluster system are expanded into three cluster system, i.e. including three
A region；
By runge kutta method determine three cluster system receiving end electric network fault cut off when generator rotor angle it is poor, according to generator rotor angle difference and
Maximum excision angle, which calculates, accelerates area and retardation area, and then determines stability margin；
Inertia time constant, the duration of failure and the relation of stability margin are analyzed, obtains inertia time constant, failure
Influence of the duration to system stability.
It is described that receiving end power grid will be sent to be reduced to two cluster system, and it is specific that two cluster system are expanded to three cluster system
For：
1) receiving end power grid will be sent to be reduced to 2 rank models of two cluster system, and obtains the equation of motion of rotor relative rotation speed；
2) the three cluster system equations of motion are converted into two two cluster system equations of motion.
It is described by runge kutta method determine three cluster system receiving end electric network fault cut off when generator rotor angle it is poor, according to generator rotor angle
Difference and maximum excision angle calculate and accelerate area and retardation area, and then determine that stability margin is specially：
1) generator rotor angle when failure removal is determined by runge kutta method is poor：
2) maximum excision angle is obtained according to generator rotor angle difference, is calculated according to maximum excision angle and accelerate area and retardation area；
3) difference of the retardation area in region 1,2 and region 2,3 with accelerating area is obtained respectively, by difference and deceleration face
Product is removed, respectively the stability margin using business as region 1,2 and region 2,3；
4) stability margin using the smaller value of region 1,2 and the stability margin in region 2,3 as whole system.
The analysis inertia time constant, the duration of failure and the relation of stability margin, obtain inertia time constant,
Influence of the duration of failure to system stability be specially：
1 generator inertia time constant of region is bigger, and system stability margin is bigger, and 1 generator inertia time of region is with being
The system proportional relation of maintenance level；
3 generator inertia time constant of region is bigger, and system stability margin is smaller, 3 generator inertia time constant of region
It is in inverse relation with system maintenance level；
The duration of failure is longer, and system stability margin is smaller, and the stability of trouble duration and system is in inverse ratio
Relation.
The beneficial effect of technical solution provided by the invention is：
(1) since three cluster system of sending end of the prior art is there are two stable modes to intercouple, solution can not be used
The mode of analysis decouples, but of the invention according to the intrinsic period proportional relation of two stable modes of particular system, can be approximate real
Interactional Decoupling Analysis between existing pattern；
(2) present invention analyzes the relation that influences each other between 2 patterns, such as：After the impact of multiple-circuit line commutation failure,
Coupling between sending end three cluster system, two stable modes will cause respective stable mode to accelerate area increase, deceleration face
Product reduces, therefore influencing each other between pattern is so that the bad stability of system；
(3) present invention can obtain the influence that different ballasts produce, such as a three cluster system failure side group of planes of sending end
Rotary inertia is bigger, and opposite side group of planes rotary inertia is smaller, and system maintenance level is higher；And medial side group of planes rotary inertia is with being
The relation of system maintenance level can also influence the maintenance level of system there are key factors such as flex point, trouble durations.
Brief description of the drawings
Fig. 1 be a kind of multiple-circuit line commutation failure after system transient stability evaluation index computational methods flow chart；
Fig. 2 is the wiring diagram of the valve systems such as two machine alternating current-direct currents；
Fig. 3 is the wiring diagram of the valve systems such as three machine alternating current-direct currents；
Fig. 4 is the schematic diagram of runge kutta method；
Fig. 5 is the calculation flow chart of fourth-order Runge-Kutta method；
Fig. 6 is influence schematic diagram of the change of inertia time constant M2 to system stability margin.
Embodiment
To make the object, technical solutions and advantages of the present invention clearer, embodiment of the present invention is made below further
It is described in detail on ground.
Embodiment 1
The transient stability evaluation index computational methods of system after a kind of multiple-circuit line commutation failure, referring to Fig. 1, the calculating side
Method comprises the following steps：
101：Receiving end power grid will be sent to be reduced to two cluster system, and two cluster system are expanded into three cluster system, i.e. bag
Include three regions；
102：Generator rotor angle when determining that the receiving end electric network fault of three cluster system is cut off by runge kutta method is poor, according to generator rotor angle
Difference and maximum excision angle calculate and accelerate area and retardation area, and then determine stability margin；
103：Analyze inertia time constant, the duration of failure and the relation of stability margin, obtain inertia time constant,
Influence of the duration of failure to system stability.
Wherein, in step 101 receiving end power grid will be sent to be reduced to two cluster system, and two cluster system is expanded into three machines
Group system be specially：
1) receiving end power grid will be sent to be reduced to 2 rank models of two cluster system, and obtains the equation of motion of rotor relative rotation speed；
2) the three cluster system equations of motion are converted into two two cluster system equations of motion.
Wherein, work(when determining that the receiving end electric network fault of three cluster system is cut off by runge kutta method in step 102
Angular difference, calculates according to generator rotor angle difference and maximum excision angle and accelerates area and retardation area, and then determines that stability margin is specially：
1) generator rotor angle when failure removal is determined by runge kutta method is poor：
2) maximum excision angle is obtained according to generator rotor angle difference, is calculated according to maximum excision angle and accelerate area and retardation area；
3) difference of the retardation area in region 1,2 and region 2,3 with accelerating area is obtained respectively, by difference and deceleration face
Product is removed, respectively the stability margin using business as region 1,2 and region 2,3；
4) stability margin using the smaller value of region 1,2 and the stability margin in region 2,3 as whole system.
Wherein, the analysis inertia time constant in step 103, the duration of failure and the relation of stability margin, obtain
The influence of inertia time constant, the duration of failure to system stability is specially：
1 generator inertia time constant of region is bigger, and system stability margin is bigger, and 1 generator inertia time of region is with being
The system proportional relation of maintenance level；
3 generator inertia time constant of region is bigger, and system stability margin is smaller, 3 generator inertia time constant of region
It is in inverse relation with system maintenance level；
The duration of failure is longer, and system stability margin is smaller, and the stability of trouble duration and system is in inverse ratio
Relation.
In conclusion two machine systems are expanded to actual three by the embodiment of the present invention by above-mentioned steps 101- steps 103
Cluster system, critical clearing angle is determined using runge kutta method, is calculated the stability margin of electric system, is met in practical application
A variety of needs.
Embodiment 2
The scheme in embodiment 1 is further introduced with reference to specific calculation formula, Fig. 1-Fig. 6, example,
It is described below：
201：Receiving end power grid will be sent to be reduced to two cluster system, and two cluster system are expanded into three cluster system；
Wherein, which is specially：
1) receiving end power grid will be sent to be reduced to 2 rank models of two cluster system, and obtains the equation of motion of rotor relative rotation speed；
In practical power systems, for the ease of analyze stable problem physical essence, will send receiving end power grid be reduced to as
Two cluster system shown in Fig. 1.
In Fig. 2, region 1,2 is equivalent sending and receiving-end system, E1、E2For sending end, the equivalent generator of receiving-end system
Built-in potential, ∠ δ1、∠δ2It is then sending end, the equivalent generator rotor angle of receiving-end system, U1、U2For sending end, the equivalent generator end of receiving-end system
Voltage, x1、x2For sending end, the equivalent generator internal reactance of receiving-end system, PM1、PM2For sending end, the equivalent generator of receiving-end system
Mechanical output, PL1、PL2For sending end, the duty value power of receiving-end system, x12For equivalent line reactance, PD1For three times direct currents
General power.
Using the simplified analysis model shown in Fig. 2 as research object, analyze sending end power grid and receiving end interconnecting ties generator rotor angle is steady
Determine the Physical Mechanism of problem, formula (1) is 2 rank models of two cluster system：
In formula：For the rotor angle rotating speed of unit i；ωiFor the rotating speed of unit i；For the acceleration of unit i；MiFor unit
The inertia time constant of i；PMiFor the mechanical output of unit i；PEiFor the electromagnetic power of unit i.The equivalent power generation of sending end AC network
The electromagnetic power of machine is：
PE1=PL1+PD1+Pac
(2)
Wherein, PL1For the load power of sending end power grid, PD1For the transmission power of direct current transportation passage, PacJoin for extra-high voltage
The transmission power of winding thread.The dynamical equation of sending end power grid is as follows：
Can similarly obtain receiving end power grid electromagnetic power and receiving end network equivalence machine dynamical equation it is as follows：
PE2=PL2-Pac
(4)
Wherein, PL2For the load power of receiving end power grid, dominant eigenvalues maximum is represented by：
Pacmax=E1E2/(x1+x12+x2)
(6)
Then transmission power can be expressed as on interconnection：
Pac=Pacmaxsin(δ1-δ2)
(7)
Simultaneous formula (1)~(7), abbreviation can must send the equation of motion of the relative rotation speed of receiving end unit rotor：
In formula：M1、M2The respectively inertia time constant of generator 1,2, PM1、PM2The respectively mechanical work of generator 1,2
Rate, δ12=δ1-δ2Generator's power and angle for region 1,2 is poor, and t is the time, PL1、PL2The load power of receiving end power grid is respectively sent,
PD1For the transmission power of direct current transportation passage, PacFor the transmission power of extra-high voltage interconnection.
2) two cluster system are expanded into three cluster system, the three cluster system equations of motion is converted into two two group of planes systems
The system equation of motion.
Large-sized connection electrified wire netting system is expanded into three cluster system from two cluster system, due between large-sized connection electrified wire netting
Influence each other more complicated, two cluster system can not meet to influence each other between large-sized connection electrified wire netting the analysis need of mechanism
Ask, therefore cause multiple-circuit line commutation failure to three cluster system of sending end to more accurately analyze receiving end failure from mechanism
Influence, large-sized connection electrified wire netting is expanded into three cluster system from two cluster system of step 1), receiving end failure is analyzed in mechanism
Influence of the caused multiple-circuit line commutation failure to three group of planes AC system of sending end, three cluster system are as shown in Figure 3.
In Fig. 3, region 1,2,3 is three group of planes of equivalent large regional grid, and region 1 represents Chongqing of Sichuan power grid, and region 2 represents Central China
Power grid, region 3 represent North China Power Telecommunication Network.E1、E2、E3The respectively equivalent generator built-in potential in region 1,2,3, ∠ δ1、∠δ2、∠δ3For
The equivalent generator's power and angle in region 1,2,3, U1、U2、U3For equivalent generator voltage, x1、x2、x3For equivalent generator internal reactance,
PM1、PM2、PM3For equivalent generator mechanical power, PL1、PL2、PL3For duty value power, x12、x23Respectively region 1,2 and area
The equivalent line reactance in domain 2,3, PD1、PD2Respectively 1 direct current of region, 2 direct current general power of region.
Due to equivalent line reactance x12、x23Much larger than equivalent generator internal reactance x1、x2、x3, then between region 1,2,3
Interconnect reactance X1-2、X2-3、X1-3Respectively：
Therefore, the three cluster system equations of motion of the equivalent generator in region 1,2,3 are：
Wherein, M1、M2、M3For equivalent generator inertia time constant, t is the time.
In order to which Reduced mechanisms are analyzed, it is assumed that generator built-in potential, mechanical output and load power are protected in dynamic process
Hold constant, δ12=δ1-δ2、δ23=δ2-δ3Generator's power and angle for region 1,2 and region 2,3 is poor, above-mentioned three cluster system movement
Equation can be converted into two two cluster system equations of motion：
Wherein, the 1st, the right of two equation of rotor motion is respectively equivalent mechanical power PM12(i.e.)、
PM23(i.e.), the 2nd is respectively equivalent electromagnetic power PE12(i.e. residual term on the right of first equation), PE23(i.e.
Residual term on the right of second equation).
When cycle ratio is 1 in three cluster system:It during T, can decouple as two oscillation modes, and then realize that region 1,2 is stablized
Pattern and region 2, the quantitative calculating of 3 stable modes, wherein
202：Generator rotor angle when determining that receiving end electric network fault is cut off by runge kutta method is poor, according to generator rotor angle difference and maximum excision
Angle, which calculates, accelerates area and retardation area, and then determines stability margin；
1) generator rotor angle when failure removal is determined by runge kutta method is poor：
The basic thought of Runge-Kutta method (Runge-Kutta) be using f (t, δ) at some points functional value it is linear
Multinomial is established in combination, is unfolded by Taylor's formula and is relatively determined parameter with the Taylor expansion of Initial Value Solution, so that it is guaranteed that having
Higher computational accuracy.The basic principle of runge kutta method is as shown in figure 4, SP is transverse axis in t=t in figurenWhen functional value
Initial value, TP are transverse axis in t=tnFunctional value, that is, end point values during+Δ h, EP are transverse axis in t=tnEstimate dragon during+Δ h
The estimate of Ge Kutafa, k1, k4Respectively transverse axis is in t=tnAnd t=tnSlope of curve during+Δ h, k2, k3It is transverse axis in t=
tnSlope of curve during+Δ h/2, the slope of curve of SP to EP is G-bar.
G-bar is denoted as：Wherein 0 ＜ θh＜ Δ h, Δ h are step-length, thenReferred to as section
[tn, tn+ Δ h] on G-bar.In Euler's formula, point t=t is takennWhen slope k1=f (tn,δn) it is used as G-bar
Precision it is very low.Euler's formula is rewritten into equalization formula：
Use t=tnWith t=tnSlope value k at+Δ h1With k2Average as G-barAnd t=tnIt is oblique at+Δ h
Rate value k2Then pass through Given information δnTo predict.It is as follows so as to construct p grades of Runge-Kutta method formula：
In formula：cj, ajAnd bjlIt is undetermined coefficient, and ajAnd bjlMeet
Fourth-order Runge-Kutta method has diversified forms, and this method uses most common quadravalence classics Runge-kutta formula：
Have precision high based on the Runge-Kutta method of Taylor series construction, particularly fourth-order Runge-Kutta method, program is simple
Single, calculating process is stablized, and the advantages that can easily be accommodated step-length, in view of the advantage of the algorithm uses it for electric power system transient stability
Generator rotor angle difference δ when in quantitative target to failure removal12cAnd δ23cCalculated, can accurately calculate the transient state of electric system
Stable state.Calculation flow chart is as shown in figure 5, n is iterations in Fig. 5, and N is the iteration upper limit, tnAnd δnRespectively initial time
With initial angle angle value, δn+1Poor for the generator rotor angle of output, h is trouble duration.
2) stability margin analysis is carried out to the stable mode in region 1,2：
By formula (11) the 1st, the acceleration area and retardation area that can calculate stable mode 1,2 are：
In formula, S121And S122Respectively accelerate area and retardation area, PM12For equivalent mechanical power, PE121max、PE122max、
PE123The three parts of respectively equivalent electromagnetic power, δ120、δ230The respectively generator's power and angle in region 1,2 and region 2,3 difference is first
Value, δ12cGenerator rotor angle when being cut off for region 1,2 generator failures is poor, δ12uFor region 1, the maximum excision in the 1st cycle of 2 generator
Angle.
And then obtain region 1, the stability margin A of 2 stable modes12For：
A12=(S122-S121)/S122 (17)
3) stability margin analysis is carried out to the stable mode in region 2,3：
By formula (15) the 2nd, the acceleration area and retardation area that can calculate stable mode 2,3 are：
In formula, S231And S232Respectively accelerate area and retardation area, PM23For equivalent mechanical power, PE231max、PE232max、
PE233The three parts of respectively equivalent electromagnetic power, δ23cFor region 2,3 generators failure removal when generator rotor angle it is poor, δ23s、δ23uPoint
Wei not region 2, the maximum excision angle in the 1st cycle of 3 generator and the 2nd cycle.
Therefore, region 2, the stability margin A of 3 patterns can be tried to achieve23For：
A23=(S232-S231)/S232 (20)
4) the monolithic stability nargin of three cluster system is determined.
Three cluster system inclusion regions 1,2 and 2,3 two, region stable mode, therefore the stability margin A of whole system takes
The respective stability margin A of two patterns12、A23Minimum value：
A=min (A12,A23)
(21)
203：Analyze inertia time constant, the duration of failure and the relation of stability margin, obtain inertia time constant,
Influence of the duration of failure to system stability.
1st, for two machine systems, if fault disturbance occurs in region 1, for region 1,2 patterns, 1 generator of region
Inertia time constant is bigger, 2 generator inertia time constant of region is smaller, and system stability margin is bigger, then region 1,2 patterns
Maintenance level is higher；
2nd, for three machine systems, 1 generator inertia time constant of region is bigger, and system stability margin is bigger, region 1
Generator inertia time and the proportional relation of system maintenance level, 3 generator inertia time constant of region is bigger, and system is stablized abundant
Spend smaller, 3 generator inertia time constant of region and system maintenance level are in inverse relation.
3rd, the duration of failure is longer, and system stability margin is smaller, and the stability of trouble duration and system is in anti-
The relation of ratio.
In conclusion former two machine system of sending end is expanded to reality by the embodiment of the present invention by above-mentioned steps 201- steps 203
Three cluster system on border, critical clearing angle is determined using runge kutta method, is calculated the stability margin of electric system, is met reality
A variety of needs in.
Embodiment 3
Feasibility verification is carried out to the scheme in Examples 1 and 2 with reference to specific experimental data, table 1- tables 4, is referred to
It is described below：
First, the transient stability of two machine systems is analyzed
Using the PSD-BPA of Chinese DianKeYuan exploitation, (simulated program is those skilled in the art institute as simulated program
Known, the embodiment of the present invention does not repeat this), three phase short circuit fault occurs for receiving-end system, triggers direct current PD1Generation commutation is lost
Lose, the stability of electric system has system stabilization and the unstable two states of system, and system, which is stablized, refers to all hairs after failure
The opposite generator rotor angle difference maximum Δ δ of motormax360 ° of ＜, system is unstable to refer to that the opposite generator rotor angle of all generators after failure is poor
Maximum Δ δmax>=360 °, the influence of analysis rotary inertia and trouble duration to system stability.
(1) influence of the unit set inertia time constant to transient stability
When influences of the different inertia time constant M1 to stability is analyzed in two machine systems, the inertial time of generator 2 is taken
Between constant M2=20, during analysis influences of the inertia time constant M2 to stability, take the inertia time constant M1=of generator 1
20, other parameters are constant.Two machine system generator inertia time constants are as shown in table 1 to stability influence.
Influence of the 1 liang of machine system inertia time constant of table to stability margin
As shown in Table 1：First, influences of the inertia time constant M1 to stability margin is analyzed, as inertia time constant M1=
It is 0.9400 to accelerate area when 10, and retardation area 1.4986, power system stability nargin minimum 0.5943, works as inertia time
It is 0.0345 to accelerate area during constant M1=100, and retardation area 1.6111, power system stability nargin is up to 45.6986,
It can be seen that inertia time constant M1 is bigger, the generator rotor angle difference of generator 1 is smaller, accelerates area to reduce, retardation area is bigger, inertia time
Influences of the constant M1 to stability is proportional；Then, influences of the inertia time constant M2 to stability margin is analyzed, works as inertia
It is 0.3885 to accelerate area during time constant M2=10, and retardation area 1.5498, power system stability nargin is up to
2.9892, it is 1.0064 to accelerate area as inertia time constant M2=100, retardation area 1.5569, power system stability
Nargin minimum 2.9892, it is seen that when inertia time constant M1 is bigger, the generator rotor angle difference of generator 1 is bigger, accelerates area increase, subtracts
Fast area is smaller, and influences of the inertia time constant M2 to stability is inversely.
(2) influence of the trouble duration to stability
As inertia time constant M1=20, M2=20, when other specification is constant, the acceleration-deceleration of different faults duration
Area is as shown in table 2.
Influence of 2 trouble duration of table to stability margin
As shown in Table 2：When trouble duration is 0.1s, it is 0.6135 to accelerate area, retardation area 1.5503, electricity
Force system stability margin is more than zero for 1.5270, and system is stablized；When trouble duration is 0.2s, acceleration area is
1.9672, retardation area 0.8124, power system stability nargin is less than zero for -0.5870, system unstability.Understand with failure
The increase of duration, acceleration area is bigger, and retardation area is smaller, and retardation area, which is more than, when system is stablized accelerates area, system
Retardation area, which is less than, during unstability accelerates area.
The analysis of two machine system examples more than, this method is preferable in the analytical effect of two group of planes, it could be assumed that：
The increase of sending inertia time constant can improve stability, proportional；Receiving-end system inertia time constant increase makes surely
Qualitative reduction, inversely.It is but synchronous by actual bulk power grid operation characteristic and emulation experience, sending end North China-Central China
Power grid includes Chongqing of Sichuan, Central China Dong Sisheng, three, North China Coherent Generator Group, and a Chongqing of Sichuan group of planes, Central China Dong Sisheng group of planes, a North China group of planes are formed
Sending end three group of planes AC system of one series connection, Chongqing Hubei Province section of Chongqing of Sichuan-Central China group of planes and the long south of Central China-North China group of planes
Line is the weak interconnection weakness section of North China-Central China synchronised grids.Therefore traditional two group of planes analysis methods can not be fully met
The analysis requirement of actual electric network.In view of two machine systems can not determine Chongqing of Sichuan, Central China and three group of planes inertia time constant of North China to being
The influence situation and stable mechanism problem for stability of uniting, propose stable mechanism analysis and quantitative assessing index based on three machine systems
Definite method.
2nd, the transient stability of three machine systems is analyzed
Using the PSD-BPA of Chinese DianKeYuan exploitation as simulated program, the system wiring figure according to Fig. 6, builds
The valve system examples such as three machine alternating current-direct currents.Fault type triggers direct current 1 and direct current 2 commutation failure at the same time for three-phase shortcircuit, and then
Analyze the influence of three machine system inertia time constants and trouble duration to stability.
(1) influence of the turbine generator inertia to transient stability
In three machine systems, when analyzing influences of the inertia time constant M1 to stability, the inertial time of generator 2 and 3 is taken
Between constant M2=120s, M3=180s, when analyzing influences of the different inertia time constant M2 to stability, take generator 1 and 3
Inertia time constant is respectively M1=60s, M3=180s, when analyzing influences of the different inertia time constant M3 to stability, is taken
The inertia time constant of generator 1 and 2 is respectively M1=60s, M2=60s, and other parameters are constant.Three machine system generator inertia
Time constant is as shown in table 3 to stability influence.
The correspondence of 3 inertia time constant M1 of table and acceleration-deceleration area
First, influences of the inertia time constant M1 to stability margin, the stable mode as inertia time constant M1=60s are analyzed
Formula A12With stable mode A23Stability margin it is smaller, monolithic stability nargin min (A12,A23) minimum 3.39, as M1=90s
Stable mode A12With stable mode A23Stability margin it is larger, monolithic stability nargin min (A12,A23) minimum 6.35, it is seen that send
The changing rule of end system inertia time constant M1 is similar to two machine systems, and inertia time constant M1 values are bigger, stable mode A12
With stable mode A23Generator rotor angle difference it is smaller, stability margin increase, stability margin depends on stable mode A23, inertia time constant
Influences of the M1 to stability is proportional.
Secondly, influences of the analysis inertia time constant M2 to stability margin, stablizes as inertia time constant M2=100s
Mode A12With stable mode A23Stability margin it is larger, monolithic stability nargin min (A12,A23) depend on A23For 3.28, when used
Stable mode A during property time constant M2=120s12With stable mode A23Stability margin be respectively 3.39 and 3.40 basic phases
Deng monolithic stability nargin min (A12,A23) depend on A12For 3.39, if stable mode A during inertia time constant M2=140s12
With stable mode A23Stability margin be respectively 2.51 and 4.12, monolithic stability nargin min (A12,A23) depend on A12For 2.51,
It can be seen that inertia time constant M2 is bigger, stable mode A12The bigger stability margin of generator rotor angle difference reduce, stable mode A23Generator rotor angle it is poor
Smaller stability margin increase, monolithic stability nargin is by A12, A23Alternately determining, the critical value of inertia time constant is M2=120s,
Situation directly perceived is as shown in Figure 6.
Finally, influences of the inertia time constant M3 to stability margin is analyzed, is stablized as inertia time constant M3=120s
Mode A12With stable mode A23Stability margin it is maximum be respectively 12.57 and 4.26, monolithic stability nargin min (A12,A23) minimum
For 4.26, the stable mode A as inertia time constant M3=220s12With stable mode A23Stability margin minimum be respectively
12.01 and 2.89, monolithic stability nargin min (A12,A23) minimum 2.89, it is seen that the change of receiving-end system inertia time constant M3
Law is similar to two machine systems, and inertia time constant M3 values are bigger, stable mode A12With stable mode A23Generator rotor angle difference get over
Small, stability margin reduces, and stability margin depends on stable mode A23, influences of the inertia time constant M3 to stability be inversely proportional pass
System.
(2) influence of the trouble duration to transient stability
When the inertia time constant of generator 1,2 and 3 is respectively 60s, 120s and 180s, in trouble duration
When changing between [0.1s 0.3s], influence of the different faults duration to three machine system stability margins is as shown in table 4
The acceleration-deceleration area correspondence of 4 different faults duration of table
As shown in Table 4：When trouble duration is 0.1s, the stability margin of stable mode A12 and stable mode A23 is most
Big is respectively 17.76 and 16.37, monolithic stability nargin min (A12,A23) minimum 16.37, with the increasing of trouble duration
Add, the stability margin of two stable modes all decreases；Stable mode A12 and stable mode when trouble duration is 0.2s
The of substantially equal stability margin of A23 is respectively 3.39 and 3.40, monolithic stability nargin min (A12,A23) it is 3.39；Failure continues
It is respectively 0.32 and 0.93 that the stability margin of stable mode A12 and stable mode A23 is minimum when time is 0.3s, and monolithic stability is abundant
Spend min (A12,A23) it is 0.32.It can be seen that with the increase of system failure duration, stable mode A12With stable mode A23It is steady
Determine nargin all reducing, and stable mode A12Reduction speed be faster than stable mode A23。
This method have studied the quantitative calculation method of three group of planes stability of sending end after multiple-circuit line commutation failure, obtain following
Main Conclusions：
(1) the quantitative calculating of electric power system transient stability index can be realized with runge kutta method, there is higher assessment essence
Degree, the quantitative analysis available for actual electric network stability.
(2) three cluster system of sending end can not use the method for parsing to decouple, still there are two stable modes to intercouple
, can interactional decoupling between approximate implementation pattern according to the intrinsic period proportional relation of two stable modes of particular system
Analysis.
(3) three cluster system failure side group of planes rotary inertia of sending end is bigger, and opposite side group of planes rotary inertia is smaller, and system is steady
It is fixed horizontal higher, and there are the pass such as flex point, trouble duration for the relation of medial side group of planes rotary inertia and system maintenance level
Key factor can also influence system maintenance level.
In conclusion this method expands to three machine systems on the basis of two machine system stable mechanisms, runge kutta method is used
Determine critical clearing angle, and then calculate the stability margin of electric system, so as to preferably analyze stable mechanism, and realize multiple
The quantitative calculating of miscellaneous system.
To the model of each device in addition to specified otherwise is done, the model of other devices is not limited the embodiment of the present invention,
As long as the device of above-mentioned function can be completed.
It will be appreciated by those skilled in the art that attached drawing is the schematic diagram of a preferred embodiment, the embodiments of the present invention
Sequence number is for illustration only, does not represent the quality of embodiment.
The foregoing is merely presently preferred embodiments of the present invention, is not intended to limit the invention, it is all the present invention spirit and
Within principle, any modification, equivalent replacement, improvement and so on, should all be included in the protection scope of the present invention.
Claims (4)
1. the computational methods of the transient stability evaluation index of system, its feature are being after a kind of multiple-circuit line commutation failure, institute
Computational methods are stated to comprise the following steps：
Receiving end power grid will be sent to be reduced to two cluster system, and two cluster system are expanded into three cluster system, i.e. including three areas
Domain；
Generator rotor angle when determining that the receiving end electric network fault of three cluster system is cut off by runge kutta method is poor, according to generator rotor angle difference and maximum
Cut off angle and calculate and accelerate area and retardation area, and then determine stability margin；
Analyze inertia time constant, the duration of failure and the relation of stability margin, obtain inertia time constant, failure is held
Continuous influence of the time to system stability.
2. the calculating side of the transient stability evaluation index of system after a kind of multiple-circuit line commutation failure according to claim 1
Method, it is characterised in that it is described that receiving end power grid will be sent to be reduced to two cluster system, and two cluster system are expanded into three cluster system
Specially：
1) receiving end power grid will be sent to be reduced to 2 rank models of two cluster system, and obtains the equation of motion of rotor relative rotation speed；
2) the three cluster system equations of motion are converted into the equation of motion of the rotor relative rotation speed of two two cluster system.
3. the calculating side of the transient stability evaluation index of system after a kind of multiple-circuit line commutation failure according to claim 1
Method, it is characterised in that it is described by runge kutta method determine three cluster system receiving end electric network fault cut off when generator rotor angle it is poor, root
Calculate according to generator rotor angle difference and maximum excision angle and accelerate area and retardation area, and then determine that stability margin is specially：
1) generator rotor angle when failure removal is determined by runge kutta method is poor：
2) maximum excision angle is obtained according to generator rotor angle difference, is calculated according to maximum excision angle and accelerate area and retardation area；
3) difference of the retardation area in region 1,2 and region 2,3 with accelerating area is obtained respectively, and difference and retardation area are done
Remove, the stability margin using business as region 1,2 and region 2,3；
4) stability margin using the smaller value of region 1,2 and the stability margin in region 2,3 as whole system.
4. the calculating side of the transient stability evaluation index of system after a kind of multiple-circuit line commutation failure according to claim 3
Method, it is characterised in that analysis inertia time constant, the duration of failure and the relation of stability margin, obtain inertial time
Between the influence of constant, the duration of failure to system stability be specially：
1 generator inertia time constant of region is bigger, and system stability margin is bigger, and 1 generator inertia time of region and system are steady
Fixed horizontal proportional relation；
3 generator inertia time constant of region is bigger, and system stability margin is smaller, and 3 generator inertia time constant of region is with being
Maintenance level of uniting is in inverse relation；
The duration of failure is longer, and system stability margin is smaller, and the stability of trouble duration and system is in inverse relation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711448501.6A CN108023362A (en) | 2017-12-27 | 2017-12-27 | The computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711448501.6A CN108023362A (en) | 2017-12-27 | 2017-12-27 | The computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108023362A true CN108023362A (en) | 2018-05-11 |
Family
ID=62071814
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711448501.6A Pending CN108023362A (en) | 2017-12-27 | 2017-12-27 | The computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108023362A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109802450A (en) * | 2019-01-10 | 2019-05-24 | 东北电力大学 | The method of AC system interconnection ability to transmit electricity is improved under multiple-circuit line failure |
| CN109888814A (en) * | 2019-03-21 | 2019-06-14 | 重庆大学 | Suppressing method is latched based on the continuous commutation failure direct current for perfecting direct-current emergency support |
| CN110086206A (en) * | 2019-03-11 | 2019-08-02 | 昆明理工大学 | A kind of extension one machine infinity bus system Transient angle stability analysis method containing blower |
| CN110187201A (en) * | 2019-04-24 | 2019-08-30 | 中国电力科学研究院有限公司 | Consider the direct-current commutation failure method of discrimination of alternating current-direct current interaction |
| CN111162557A (en) * | 2020-01-17 | 2020-05-15 | 华北电力大学 | Sending end system transient stability margin adjusting method and system |
| CN113193598A (en) * | 2021-05-31 | 2021-07-30 | 重庆大学 | New energy grid-connected inverter transient stability margin evaluation method |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103605871A (en) * | 2013-12-03 | 2014-02-26 | 国家电网公司 | Large power system emulation analysis method based on direct-current external characteristic fitting |
| JP2017112709A (en) * | 2015-12-16 | 2017-06-22 | 株式会社日立製作所 | Voltage stability monitoring device and method |
-
2017
- 2017-12-27 CN CN201711448501.6A patent/CN108023362A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103605871A (en) * | 2013-12-03 | 2014-02-26 | 国家电网公司 | Large power system emulation analysis method based on direct-current external characteristic fitting |
| JP2017112709A (en) * | 2015-12-16 | 2017-06-22 | 株式会社日立製作所 | Voltage stability monitoring device and method |
Non-Patent Citations (4)
| Title |
|---|
| 屠竞哲，等: "多回直流换相失败后送端三机群系统稳定机理及影响因素研究", 《电网技术》 * |
| 屠竞哲，等: "大规模直流异步互联系统受端故障引发送端稳定破坏的机理分析", 《中国电机工程学报》 * |
| 张辉: "电力系统暂态稳定性的数值仿真研究", 《计算机仿真》 * |
| 汪闻涛，等: "华北－华中特高压交直流线路相互作用解析分析", 《电力建设》 * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109802450A (en) * | 2019-01-10 | 2019-05-24 | 东北电力大学 | The method of AC system interconnection ability to transmit electricity is improved under multiple-circuit line failure |
| CN109802450B (en) * | 2019-01-10 | 2022-04-22 | 东北电力大学 | Method for improving power transmission capacity of alternating current system tie line under multi-circuit direct current fault |
| CN110086206A (en) * | 2019-03-11 | 2019-08-02 | 昆明理工大学 | A kind of extension one machine infinity bus system Transient angle stability analysis method containing blower |
| CN109888814A (en) * | 2019-03-21 | 2019-06-14 | 重庆大学 | Suppressing method is latched based on the continuous commutation failure direct current for perfecting direct-current emergency support |
| CN110187201A (en) * | 2019-04-24 | 2019-08-30 | 中国电力科学研究院有限公司 | Consider the direct-current commutation failure method of discrimination of alternating current-direct current interaction |
| CN110187201B (en) * | 2019-04-24 | 2021-11-16 | 中国电力科学研究院有限公司 | Direct current commutation failure judgment method considering alternating current and direct current interaction |
| CN111162557A (en) * | 2020-01-17 | 2020-05-15 | 华北电力大学 | Sending end system transient stability margin adjusting method and system |
| CN111162557B (en) * | 2020-01-17 | 2021-03-23 | 华北电力大学 | Sending end system transient stability margin adjusting method and system |
| CN113193598A (en) * | 2021-05-31 | 2021-07-30 | 重庆大学 | New energy grid-connected inverter transient stability margin evaluation method |
| CN113193598B (en) * | 2021-05-31 | 2022-09-30 | 重庆大学 | New energy grid-connected inverter transient stability margin evaluation method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108023362A (en) | The computational methods of the transient stability evaluation index of system after multiple-circuit line commutation failure | |
| Wu et al. | Design-oriented transient stability analysis of grid-connected converters with power synchronization control | |
| Yan et al. | PMU-based monitoring of rotor angle dynamics | |
| Farantatos et al. | A predictive generator out-of-step protection and transient stability monitoring scheme enabled by a distributed dynamic state estimator | |
| CN108092304A (en) | Power system transient stability method of discrimination based on phase path Yu relative kinetic energy change rate | |
| CN107526901B (en) | Power system step-out center positioning and oscillation center tracking system and method thereof | |
| Sun et al. | An adaptive power system equivalent for real-time estimation of stability margin using phase-plane trajectories | |
| Farantatos et al. | A predictive out of step protection scheme based on PMU enabled dynamic state estimation | |
| WO2014107997A1 (en) | Method for real-time discrimination of transient power angle destabilization based on actually-measured response information | |
| CN110135039A (en) | Wind-powered electricity generation collects regional non-equilibrium among three phase voltages and determines method and device | |
| CN104316827B (en) | Positioning method for oscillation center of electric power system | |
| Wang et al. | Fault diagnosis based on current signature analysis for stator winding of Doubly Fed Induction Generator in wind turbine | |
| Pan et al. | A practical short-circuit current calculation method for DFIG-based wind farm considering voltage distribution | |
| CN109617061A (en) | The fast evaluation method of stability margin in the case of a kind of unbalanced fault | |
| Echeverría et al. | Comprehensive approach for prediction and assessment of power system transient stability in real-time | |
| CN105244887A (en) | Closed-loop control method for transient power angle instability of power system | |
| Lei et al. | Efficient Power System Transient Simulation Based on Frequency Response Optimized Integrators Considering Second Order Derivative | |
| CN109301841A (en) | Electric power system transient stability comprehensive distinguishing method and system based on WAMS actual measurement track | |
| CN108988320A (en) | Electrical Power System Dynamic element responds characteristic is to Enhancement of Transient Voltage Stability impact analysis method | |
| CN104866973A (en) | Rapid setting method for transient stability control strategy table of power system | |
| Pinto et al. | A fast methodology for solving power flows in hybrid ac/dc networks: The European North Sea Supergrid case study | |
| Cao et al. | Faster-than-real-time hardware emulation of extensive contingencies for dynamic security analysis of large-scale integrated AC/DC grid | |
| Gurusinghe et al. | Co-simulation of power system and synchrophasor communication network on a single simulation platform | |
| Padhi et al. | Solution of swing equation for transient stability analysis in dual-machine system | |
| CN105305392A (en) | Symmetrical component method for short circuit calculation of voltage-controlled type IIDG included power distribution network |
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 | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20180511 |
|
| WD01 | Invention patent application deemed withdrawn after publication |