CN109921381B - Chopper protection action criterion method for double-fed motor - Google Patents
Chopper protection action criterion method for double-fed motor Download PDFInfo
- Publication number
- CN109921381B CN109921381B CN201910248078.8A CN201910248078A CN109921381B CN 109921381 B CN109921381 B CN 109921381B CN 201910248078 A CN201910248078 A CN 201910248078A CN 109921381 B CN109921381 B CN 109921381B
- Authority
- CN
- China
- Prior art keywords
- rotor
- fault
- stator
- double
- terminal voltage
- 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.)
- Active
Links
- 238000000034 method Methods 0.000 title claims abstract description 16
- 230000001052 transient effect Effects 0.000 claims description 14
- 230000004907 flux Effects 0.000 claims description 7
- 238000004804 winding Methods 0.000 claims description 6
- 230000008878 coupling Effects 0.000 claims description 4
- 238000010168 coupling process Methods 0.000 claims description 4
- 238000005859 coupling reaction Methods 0.000 claims description 4
- 230000001939 inductive effect Effects 0.000 claims description 4
- 238000013178 mathematical model Methods 0.000 claims description 4
- 230000005284 excitation Effects 0.000 claims description 3
- 230000001360 synchronised effect Effects 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
Images
Landscapes
- Control Of Eletrric Generators (AREA)
Abstract
The invention discloses a Chopper protection action criterion method for a double-fed motor, which is characterized in that when the double-fed motor has a short-circuit fault, the terminal voltage after the fault is taken as a Chopper protection action criterion.
Description
Technical Field
The invention relates to the field of wind power plant safety, in particular to a judgment method for a protection action of a doubly-fed motor Chopper.
Background art:
at present, Chopper protection is added to most double-fed wind turbine generators, the low-voltage ride through capability of a double-fed motor is improved, and the safe and stable operation of a wind power plant is guaranteed. The protection action criterion refers to the basis for judging whether Chopper protection acts after disturbance occurs. After a fault occurs, Chopper protection is usually put into use when the voltage of a direct-current bus is set to be larger than a certain value in order to avoid damage to a converter, but researchers are difficult to judge whether Chopper protection acts from external data, so that parameters which are easy to obtain are needed to serve as criteria for Chopper protection action of a double-fed motor at present.
Disclosure of Invention
The invention aims to provide a Chopper protection action criterion method for a double-fed motor, so as to solve the defects in the prior art.
A Chopper protection action criterion method for a double-fed motor specifically comprises the following steps:
step 1, analyzing a double-fed wind driven generator mathematical model and transient characteristics thereof after a fault;
step 2, deducing a rotor voltage expression of the doubly-fed motor when Chopper protection is not put into operation according to the mathematical model of the doubly-fed wind generator and the transient characteristic of the doubly-fed wind generator;
step 3, making the rotor voltage equal to the direct current bus voltage limiting threshold value, and obtaining a set of terminal voltage and time { (K)di,ti) Get K in the setdThe minimum value of (2) is the limit value of the calculated terminal voltage drop coefficient;
step 4, obtaining a limit value of Chopper protection action fault post-terminal voltage according to the coefficient, wherein the limit value is a Chopper protection action criterion of the doubly-fed wind driven generator disclosed by the invention,
the expression for the rotor voltage is:
where t is time, t0For the occurrence of short-circuit fault, RrAs rotor resistance, ωp＝ωs–ωrIs the slip angular velocity, omegarIs the angular speed, omega, of the rotorsFor synchronizing the rotational speeds, s ═ ωp/ωsIn order to obtain a slip ratio,
is rotor transient equivalent inductance, LsIs equivalent inductance of stator winding, LrIs equivalent inductance of rotor winding, LmIs an excitation inductor;
Making the rotor voltage equal to a defined threshold value of the DC bus voltage, i.e.
Get { (K)di,ti) K in the setdiMinimum value of (K)dminI.e. the calculated terminal voltage drop coefficient Kd。
Therefore, the Chopper protection action criterion of the doubly-fed wind generator disclosed by the invention is as follows:
us1＝(1-Kd)us0
us1the voltage at the end of the fault is the Chopper protection action criterion of the doubly-fed wind generator, and if the actual voltage after the fault is less than or equal to us1The Chopper protection is put in, otherwise, the Chopper protection is not put in.
The invention has the advantages that: compared with the Chopper protection action criterion method of the existing double-fed wind generating set, on one hand, the criterion belongs to an external easy-to-observe parameter and is easy to obtain; on the other hand, the criterion is simple and clear, so that researchers can very easily judge whether Chopper protection acts or not, and the method has important significance for deeply developing fault current analysis of the wind power plant.
Drawings
Fig. 1 is an equivalent circuit diagram of the present invention.
Fig. 2 is a transient equivalent circuit diagram of the doubly-fed motor of the present invention.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.
As shown in fig. 1 and fig. 2, a method for determining Chopper protection action of a doubly-fed motor includes the following steps:
step 1, suppose when t0When a three-phase short circuit fault occurs on the stator side, analyzing the transient characteristic after the fault according to the electromagnetic transient equation of the doubly-fed wind generator under the space rotating coordinate system;
the classical voltage flux linkage equation is:
the voltage expression of the rotor of the doubly-fed motor when Chopper protection is not put into operation can be deduced from the equation set;
step 2, according to an electromagnetic transient equation of the doubly-fed wind generator under a space rotating coordinate system, deducing a voltage expression of a rotor of the doubly-fed motor when Chopper protection is not put into operation:
where t is time, t0For the occurrence of short-circuit fault, RrAs rotor resistance, ωp＝ωs–ωrIs the slip angular velocity, omegarIs the angular speed, omega, of the rotorsFor synchronizing the rotational speeds, s ═ ωp/ωsIn order to obtain a slip ratio,
is rotor transient equivalent inductance, LsIs equivalent inductance of stator winding, LrIs equivalent inductance of rotor winding, LmIs an excitation inductor;
Step 3, making the rotor voltage equal to the direct current bus voltage limiting threshold value, namely
Get { (K)di,ti) K in the setdiMinimum value of (K)dminI.e. the calculated terminal voltage drop coefficient Kd。
Step 4, obtaining a limit value of Chopper protection action fault post-terminal voltage according to the coefficient, wherein the limit value is a Chopper protection action criterion of the doubly-fed wind driven generator disclosed by the invention, namely
us1＝(1-Kd)us0
us1The voltage at the end of the fault is the Chopper protection action criterion of the doubly-fed wind generator, and if the actual voltage after the fault is less than or equal to us1The Chopper protection is put in, otherwise, the Chopper protection is not put in.
During research, the Chopper protection action condition is obtained through the method, and then subsequent short-circuit current calculation or related research is carried out.
Based on the above, when judging whether Chopper protection acts, the terminal voltage after the fault is used as Chopper protection action criterion, compared with the Chopper protection action criterion method of the existing double-fed wind generating set, on one hand, the new criterion belongs to an external easy-to-observe parameter and is easy to obtain; on the other hand, the criterion disclosed by the invention is simple and clear, so that a researcher can very easily judge whether Chopper protection acts or not, and the method has important significance for deeply developing fault current analysis of the wind power plant.
It will be appreciated by those skilled in the art that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The embodiments disclosed above are therefore to be considered in all respects as illustrative and not restrictive. All changes which come within the scope of or equivalence to the invention are intended to be embraced therein.
Claims (2)
1. A Chopper protection action criterion method for a double-fed motor is characterized by comprising the following steps:
analyzing a double-fed motor mathematical model and transient characteristics thereof after a fault;
obtaining a double-fed motor rotor voltage expression when Chopper protection is not put into operation according to the mathematical model and the transient characteristic;
calculating to obtain a machine terminal voltage drop coefficient through a rotor voltage expression;
obtaining a fault post-machine terminal voltage value of Chopper protection action according to the machine terminal voltage drop coefficient, namely a criterion of the Chopper protection action of the double-fed motor;
the Chopper protection action criterion method for the double-fed motor comprises the following formula:
us1＝(1-Kd)us0 (3)
us1for fault backend voltage, KdIs the terminal voltage drop coefficient u of the dual-feeder machines0For the voltage amplitude at the end of the fault, if the actual voltage after the fault is less than or equal to us1If yes, the Chopper protection is put into the device, otherwise, the Chopper protection is not put into the device;
the rotor voltage expression is:
where t is time, t0For the occurrence of a short-circuit fault, j denotes the imaginary part in the complex domain, RrAs rotor resistance, ωp＝ωs–ωrIs the slip angular velocity, omegarIs the angular speed, omega, of the rotorsFor synchronizing the rotational speeds, s ═ ωp/ωsIs slip ratio, L'rFor rotor transient equivalent inductance, irIs a rotor current space vector under dq synchronous rotation coordinate system, dq represents the coordinate system, d represents a direct axis, q represents a quadrature axis, KdIs the terminal voltage drop coefficient of the dual-feeder machine, e2For the direct-current component of the rotor-induced electromotive force e after a fault, us0For the voltage amplitude of the machine terminal before the fault, ksRepresenting the stator inductive coupling coefficient;
l 'in the rotor voltage expression'rThe equivalent formula of (a) is:
wherein L issIs equivalent inductance of stator winding, LrIs equivalent inductance of rotor winding, LmIs an excitation inductor;
i in the rotor voltage expressionrThe calculation formula of (2) is as follows:
wherein,
is a rotor current reference value, Ps,refAnd Qs,refRespectively an active power reference value and a reactive power reference value, KdFor the terminal voltage drop coefficient, psi, of the dual-feed machinesmAs the amplitude of the stator flux linkage,
is the decay time constant of the dc component of the rotor induced electromotive force e after the fault,
for the direct-current component of the rotor-induced electromotive force e after a fault, us0For the pre-fault terminal voltage magnitude, μ ═ Rr+kp+jωpL'r)/L'rAnd λ ═ ki/L'rAs a parameter variable, kpAnd kiRespectively are a proportionality coefficient and an integral time constant of the rotor current inner loop PI controller,
which is the characteristic root of some ordinary differential equation,
is the initial value of the current of the rotor,
and
respectively represent the inductive coupling coefficients of the stator and the rotor,
is an initial value of the magnetic linkage of the stator,
is an initial value of rotor flux linkage, RsAs the impedance of the stator,
is stator equivalent transient inductance, Is0Is the initial value of the stator current before the fault.
2. The Chopper protection action criterion method of the double-fed motor according to claim 1, characterized in that: the method for calculating the terminal voltage drop coefficient comprises the following steps:
when the rotor voltage amplitude is equal to the direct-current bus voltage limiting threshold value, obtaining a set of terminal voltage drop coefficients and time t at the moment, namely { (K)di,ti) The formula is:
get { (K)di,ti) K in the setdiMinimum value of (K)dminI.e. the calculated terminal voltage drop coefficient Kd，Udc.thA threshold value is defined for the dc bus voltage.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910248078.8A CN109921381B (en) | 2019-03-29 | 2019-03-29 | Chopper protection action criterion method for double-fed motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910248078.8A CN109921381B (en) | 2019-03-29 | 2019-03-29 | Chopper protection action criterion method for double-fed motor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109921381A CN109921381A (en) | 2019-06-21 |
| CN109921381B true CN109921381B (en) | 2020-12-01 |
Family
ID=66967644
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910248078.8A Active CN109921381B (en) | 2019-03-29 | 2019-03-29 | Chopper protection action criterion method for double-fed motor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109921381B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105356520A (en) * | 2015-11-24 | 2016-02-24 | 上海电力学院 | Control method for improving low voltage ride through capability of wind power plant |
| CN106777600A (en) * | 2016-12-02 | 2017-05-31 | 河海大学 | Consider the double feedback electric engine short-circuit current calculation method of Chopper protections |
| CN109444737A (en) * | 2018-09-11 | 2019-03-08 | 昆明理工大学 | It is a kind of meter and crow bar operating time of protection double-fed blower three short circuit current analytic method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2338224B1 (en) * | 2008-10-20 | 2019-10-02 | Woodward Kempen GmbH | Protection system of a doubly-fed induction machine |
| CN105259462B (en) * | 2015-11-06 | 2018-01-19 | 河海大学 | A kind of double feedback electric engine Calculation Method of Three-phase Short-circuit Current |
-
2019
- 2019-03-29 CN CN201910248078.8A patent/CN109921381B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105356520A (en) * | 2015-11-24 | 2016-02-24 | 上海电力学院 | Control method for improving low voltage ride through capability of wind power plant |
| CN106777600A (en) * | 2016-12-02 | 2017-05-31 | 河海大学 | Consider the double feedback electric engine short-circuit current calculation method of Chopper protections |
| CN109444737A (en) * | 2018-09-11 | 2019-03-08 | 昆明理工大学 | It is a kind of meter and crow bar operating time of protection double-fed blower three short circuit current analytic method |
Non-Patent Citations (1)
| Title |
|---|
| 综合Crowbar和Choppe保护的双馈风机低电压穿越仿真研究;曹鹏飞;《华北电力技术》;20170225(第2期);第49-54页，图7-9 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN109921381A (en) | 2019-06-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104836503B (en) | Double-fed aerogenerator stator short-circuit current calculation method under unbalanced fault | |
| CN108599256B (en) | Low voltage ride through control method of direct drive type wind turbine generator based on rotation speed regulation | |
| CN107425539B (en) | Enhanced low-voltage ride-through control method of doubly-fed wind turbine generator under asymmetric power grid fault | |
| WO2015035892A1 (en) | Method for calculating transient short circuit current of dfig set | |
| CN105259462B (en) | A kind of double feedback electric engine Calculation Method of Three-phase Short-circuit Current | |
| WO2013118370A1 (en) | Control device for wind turbine generator, wind turbine generator, and control method for wind turbine generator | |
| CN102570957B (en) | Control method for doubly-fed electric generator | |
| CN106777600B (en) | Consider the double feedback electric engine short-circuit current calculation method of Chopper protection | |
| CN107732969B (en) | Double-fed wind turbine generator short-circuit current calculation method considering low-voltage ride through overall process | |
| CN106452234B (en) | A kind of double-fed aerogenerator stator turn-to-turn short circuit negative-sequence current suppressing method | |
| CN104809265B (en) | Meter and the double-fed generator analogue system and method for crow bar protection | |
| CN108462207B (en) | Doubly-fed motor short-circuit current calculation method considering transient regulation and control of converter | |
| CN107918695B (en) | Doubly-fed wind turbine generator short-circuit current calculation method considering crowbar action | |
| CN110034578B (en) | Double-fed motor crowbar protection action criterion method | |
| CN104865523A (en) | Doubly-fed generator simulation system and method | |
| CN105938515A (en) | Doubly-fed motor three-phase short-circuit current practical calculation method | |
| CN109888837B (en) | Wind power plant short-circuit current calculation method based on double-fed motor crowbar protection new criterion | |
| CN109921381B (en) | Chopper protection action criterion method for double-fed motor | |
| CN105846459B (en) | The adaptive distance protection method combined based on intrinsic frequency with characteristic frequency | |
| CN117081066A (en) | Method and system for analyzing transient voltage instability of load of induction motor by considering large disturbance | |
| CN115603306A (en) | Rotor transient current-based doubly-fed wind turbine generator rotor voltage compensation method | |
| CN113285639B (en) | Method and system for determining negative sequence impedance of base frequency of double-fed induction generator system | |
| CN107069802A (en) | Double-fed fan motor unit net side current transformer current calculation method under generator terminal symmetric fault | |
| CN107480406A (en) | A kind of dynamic vector method for establishing model of double-fed fan motor unit calculation of short-circuit current | |
| CN107681940B (en) | Rotating speed monitoring method based on synchronous generator terminal electrical signal extraction |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |