阅读说明：本技术 带转子匝间短路故障运行的发电机运行控制系统及方法 (Generator operation control system and method with rotor inter-turn short circuit fault operation ) 是由 胡相余 王健 孟涛 王锐 阮柏松 陈涛 毛思锋 姜彤 张庆 陈功 于 2021-08-13 设计创作，主要内容包括：本发明属于汽轮发电机运行控制和发电机运行管理技术领域,是一种考虑带发电机转子匝间短路故障运行的发电机运行控制系统,包括：数据采集模块、数据分析处理模块、判断模块和绘图模块；数据采集模块,每过时间间隔T,获取汽轮发电机运行时励磁绕组的励磁电流数据；数据分析处理模块,利用获取的汽轮发电机运行时励磁绕组的励磁电流数据,计算时间间隔T内发电机励磁电流变化率；用于当输出匝间短路运行状态故障信号时,得到不同的匝间短路后发电机P-Q曲线变化率μ＝{μ-(1),μ-(2),μ-(3),…,μ-(N)}；判断模块,对计算得到的每个发电机励磁电流变化率进行判断；绘图模块,根据比例缩小法,绘制缩小μ倍的带匝间短路故障运行的发电机运行极限图。(The invention belongs to the technical field of turbo generator operation control and generator operation management, and relates to a generator operation control system considering turn-to-turn short circuit fault operation of a rotor with a generator, which comprises the following components: the device comprises a data acquisition module, a data analysis processing module, a judgment module and a drawing module; the data acquisition module acquires excitation current data of an excitation winding when the turbonator operates at each time interval T; the data analysis processing module is used for calculating the change rate of the excitation current of the generator within a time interval T by using the obtained excitation current data of the excitation winding when the turbonator operates; the method is used for obtaining the P-Q curve change rate mu of the generator after different turn-to-turn short circuits when outputting the turn-to-turn short circuit operation state fault signal 1 ,μ 2 ,μ 3 ,…,μ N }; the judgment module is used for judging the change rate of the excitation current of each generator obtained through calculation; a drawing module for drawing according to a scaling methodAnd (4) making a generator operation limit diagram with mu-fold reduced operation with turn-to-turn short circuit faults.)

1. An operation control system of a generator with rotor turn-to-turn short circuit fault operation, which is characterized by comprising: the device comprises a data acquisition module, a data analysis processing module, a judgment module and a drawing module;

the data acquisition module is used for acquiring exciting current data of an exciting winding when the turbonator operates at each time interval T; wherein the excitation current data comprises excitation current measurements;

the data analysis processing module is used for calculating the change rate of the excitation current of the generator within a time interval T by using the obtained excitation current data of the excitation winding when the turbonator runs;

and the data analysis processing module is used for calculating different turn-to-turn short circuit percentages when a turn-to-turn short circuit operation state fault signal is output, and looking up a P-Q operation limit change rate comparison table of the short circuit turn percentage of the generator rotor winding according to the different turn-to-turn short circuit percentages obtained by calculation to obtain different turn-to-turn short circuit back generator P-Q curve change rates which are recorded as mu- { mu ═ mu { (mu) }₁,μ₂,μ₃,…,μ_N}；

The judging module is used for judging the change rate of the excitation current of each generator obtained by calculation;

if the calculated exciting current change rate is larger than the set value of the exciting current deviation rate&Outputting a turn-to-turn short circuit operation state fault signal, calculating different turn-to-turn short circuit percentages by using a data analysis processing module, looking up a P-Q operation limit change rate comparison table of the short circuit turn percentage of a generator rotor winding according to the different turn-to-turn short circuit percentages obtained by calculation, obtaining different turn-to-turn short circuit back generator P-Q curve change rates, and recording the change rates as mu ═ mu₁,μ₂,μ₃,…,μ_N}；

If the calculated exciting current change rate is less than or equal to the exciting current deviation rate set value &, outputting a normal operating state signal;

and the drawing module is used for drawing a mu-time reduced generator operation limit diagram with turn-to-turn short circuit fault operation according to a scale reduction method.

2. The system of claim 1, further comprising: and the fault processing module is used for processing the turn-to-turn short circuit fault on line in real time according to the turn-to-turn short circuit fault severity index and the drawn generator operation limit diagram with the turn-to-turn short circuit fault operation reduced by mu times.

3. The generator operation control system with rotor turn-to-turn short circuit fault operation of claim 1, characterized in that the data analysis processing module comprises: the device comprises a reading unit, a first analysis processing unit and a second analysis processing unit;

the reading unit is used for acquiring the excitation current data of the excitation winding when the turbonator operates;

the first analysis processing unit is used for calculating the change rate of the excitation current of the generator within a time interval T according to the obtained excitation current data of the excitation winding when the turbonator runs;

wherein, a_nThe change rate of the generator exciting current in a time interval T;is T_nExciting current data of an exciting winding when the turbonator operates at any moment;is T_n+1Exciting current data of an exciting winding when the turbonator operates at any moment;

the second analysis processing unit is used for calculating turn-to-turn short circuit percentage k by using the data analysis processing module when outputting a turn-to-turn short circuit operation state fault signal;

wherein, Delta N is the number of turns of the rotor winding with turn-to-turn short circuit at the moment T; n is the number of turns of the rotor winding;the measured value of the exciting current of the excitation winding of the turbonator at the moment T;the measured value is the exciting current value of the exciting winding when the turbonator does not generate turn-to-turn short circuit;

and obtaining different turn-to-turn short circuit percentages k ═ k according to calculation₁,k₂,k₃,…,k_NLooking up a comparison table of the P-Q operation limit change rate of the short-circuit turn percentage of the generator rotor winding to obtain the P-Q curve change rate of the generator after different turn-to-turn short circuits, and recording the change rate as mu-m-mu₁,μ₂,μ₃,…,μ_N}; wherein, each turn-to-turn short circuit percentage corresponds to the P-Q curve change rate of the generator after one turn-to-turn short circuit.

4. The system of claim 1, wherein the time interval T is 0.04 s.

5. A method for controlling the operation of a generator with rotor turn-to-turn short circuit fault operation, which is implemented based on the system for controlling the operation of a generator with rotor turn-to-turn short circuit fault operation according to any one of claims 1 to 4, and which comprises:

step S1, acquiring exciting current data of an exciting winding when the turbonator operates by using a data acquisition module at each time interval T; wherein the time interval T is 0.04 s; the excitation current data includes: a measured value of an excitation current;

step S2, calculating the change rate of the generator exciting current in the time interval T by using the exciting current data of the exciting winding obtained in the step S1 when the turbonator runs through a data analysis processing module;

step S3, judging the calculated change rate of the generator exciting current by using a judging module;

if the calculated exciting current change rate is greater than the exciting current deviation rate set value &, outputting a turn-to-turn short circuit operation state fault signal, and performing the next step S4;

if the calculated exciting current change rate is less than or equal to the exciting current deviation rate set value &, outputting a normal operating state signal;

step S4, when the turn-to-turn short circuit operation state fault signal is output, the data analysis processing module is used for calculating the turn-to-turn short circuit percentage, and the turn percentage of the short circuit is used as the severity index of the turn-to-turn short circuit fault;

step S5, according to the different turn-to-turn short circuit percentages obtained through calculation, consulting the generator rotor winding short circuit turn percentage P-Q operation limit change rate comparison table to obtain the different turn-to-turn short circuit generator P-Q curve change rates, and recording as mu- { mu ═ mu [ [ the percentage of the short circuit between the two turns of the generator₁,μ₂,μ₃,…,μ_N}；

And step S6, generating a generator operation limit diagram with mu times of reduced operation of turn-to-turn short circuit faults according to a scale reduction method through a data drawing module.

6. The method of controlling operation of a generator with rotor turn-to-turn short circuit fault operation of claim 5, further comprising: and the fault processing module takes the percentage of the number of short circuit turns as the severity index of turn-to-turn short circuit faults, and processes the turn-to-turn short circuit faults in real time on line according to the severity index of the turn-to-turn short circuit faults and the drawn running limit diagram of the generator with the turn-to-turn short circuit faults running reduced by mu times, so that the normal running of a power plant is ensured.

7. The method for controlling the operation of a generator with rotor turn-to-turn short circuit operation according to claim 5, wherein the step S2 specifically comprises:

calculating the change rate of the excitation current of the generator within a time interval T according to the obtained excitation current data of the excitation winding when the turbonator operates;

wherein, a_nThe change rate of the generator exciting current in a time interval T;is T_nExciting current data of an exciting winding when the turbonator operates at any moment;is T_n+1And (3) exciting current data of the exciting winding when the turbonator operates at any time.

8. The method for controlling the operation of a generator with rotor turn-to-turn short circuit operation according to claim 5, wherein the step S5 specifically comprises:

when a turn-to-turn short circuit operation state fault signal is output, calculating a turn-to-turn short circuit percentage k by using a data analysis processing module;

wherein, Delta N is the number of turns of the rotor winding with turn-to-turn short circuit at the moment T; n is the number of turns of the rotor winding;the measured value of the exciting current of the excitation winding of the turbonator at the moment T;for exciting windings of turbonators without turn-to-turn short-circuitsA measured value of an excitation current;

and obtaining different turn-to-turn short circuit percentages k ═ k according to calculation₁,k₂,k₃,…,k_NLooking up a comparison table of the P-Q operation limit change rate of the short-circuit turn percentage of the generator rotor winding to obtain the P-Q curve change rate of the generator after different turn-to-turn short circuits, and recording the change rate as mu-m-mu₁,μ₂,μ₃,…,μ_N}。

Technical Field

The invention belongs to the technical field of operation control and generator operation management of a steam turbine generator, and particularly relates to a generator operation control system and method with rotor turn-to-turn short circuit fault operation.

Background

Rotor winding turn-to-turn short circuit faults are one of the most common forms of electrical faults in turbonators. When the number of short circuit turns is less, the fault unit can still continue to operate; however, once the number of short circuit turns is increased, the rotor may have one-point grounding and two-point grounding faults, so that the power plant must be shut down and maintained, a large amount of manpower and material resources are wasted, the cost is increased, and the working efficiency of the turbonator is reduced. Therefore, the method is necessary for carrying out online monitoring and online diagnosis on the turn-to-turn short circuit fault of the rotor winding of the turbonator, and can be used for quickly and accurately detecting the turn-to-turn short circuit fault of the rotor winding, shortening the fault processing time and reducing the shutdown cost.

In recent years, diagnosis of a short-circuit fault of a rotor winding of a steam turbine generator has been rapidly developed, and existing control methods can be generally classified into an offline detection method and an online detection method. The online detection method has the characteristic of finding faults in time, but the sensitivity of diagnosis is not high, the popularization rate is not high, the universality is poor, and the working efficiency is low. Although the off-line detection method is completed in a shutdown state, various interferences can be effectively eliminated, and the detection reliability is high, the off-line detection method can be performed only in a shutdown environment, so that the defect of a fault cannot be timely discovered.

Disclosure of Invention

In order to solve the defects in the prior art, the invention provides the generator operation control method for the operation with the rotor turn-to-turn short circuit fault, the method improves the on-line diagnosis level of the turn-to-turn short circuit fault of the rotor winding of the turbonator, provides an on-line control method for the turbonator when the turbine generator generates the turn-to-turn short circuit fault, and ensures the normal operation of the turbonator.

The invention provides a generator operation control system considering turn-to-turn short circuit fault operation of a belt rotor, which comprises: the device comprises a data acquisition module, a data analysis processing module, a judgment module and a drawing module;

the data acquisition module is used for acquiring exciting current data of an exciting winding when the turbonator operates at each time interval T; wherein the excitation current data comprises excitation current measurements;

the data analysis processing module is used for calculating the change rate of the excitation current of the generator within a time interval T by using the obtained excitation current data of the excitation winding when the turbonator runs;

and the data analysis processing module is used for calculating different turn-to-turn short circuit percentages when a turn-to-turn short circuit operation state fault signal is output, and looking up a P-Q operation limit change rate comparison table of the short circuit turn percentage of the generator rotor winding according to the different turn-to-turn short circuit percentages obtained by calculation to obtain different turn-to-turn short circuit back generator P-Q curve change rates which are recorded as mu- { mu ═ mu { (mu) }₁,μ₂,μ₃,…,μ_N}；

The judging module is used for judging the change rate of the excitation current of each generator obtained by calculation;

if the calculated exciting current change rate is larger than the set value of the exciting current deviation rate&Outputting a turn-to-turn short circuit operation state fault signal, calculating different turn-to-turn short circuit percentages by using a data analysis processing module, looking up a P-Q operation limit change rate comparison table of the short circuit turn percentage of a generator rotor winding according to the different turn-to-turn short circuit percentages obtained by calculation, obtaining different turn-to-turn short circuit back generator P-Q curve change rates, and recording the change rates as mu ═ mu₁,μ₂,μ₃,…,μ_N}；

If the calculated exciting current change rate is less than or equal to the exciting current deviation rate set value &, outputting a normal operating state signal;

and the drawing module is used for drawing a mu-time reduced generator operation limit diagram with turn-to-turn short circuit fault operation according to a scale reduction method.

As an improvement of the above technical solution, the system further includes: and the fault processing module is used for processing the turn-to-turn short circuit fault on line in real time according to the turn-to-turn short circuit fault severity index and the drawn generator operation limit diagram with the turn-to-turn short circuit fault operation reduced by mu times.

As an improvement of the above technical solution, the data analysis processing module includes: the device comprises a reading unit, a first analysis processing unit and a second analysis processing unit;

the reading unit is used for acquiring the excitation current data of the excitation winding when the turbonator operates;

the first analysis processing unit is used for calculating the change rate of the excitation current of the generator within a time interval T according to the obtained excitation current data of the excitation winding when the turbonator runs;

wherein, a_nThe change rate of the generator exciting current in a time interval T;is T_nExciting current data of an exciting winding when the turbonator operates at any moment;is T_n+1Exciting current data of an exciting winding when the turbonator operates at any moment;

the second analysis processing unit is used for calculating turn-to-turn short circuit percentage k by using the data analysis processing module when outputting a turn-to-turn short circuit operation state fault signal;

wherein, Delta N is the number of turns of the rotor winding with turn-to-turn short circuit at the moment T; n is the number of turns of the rotor winding;the measured value of the exciting current of the excitation winding of the turbonator at the moment T;the measured value is the exciting current value of the exciting winding when the turbonator does not generate turn-to-turn short circuit;

and obtaining different turn-to-turn short circuit percentages k ═ k according to calculation₁,k₂,k₃,…,k_NLooking up a comparison table of the P-Q operation limit change rate of the short-circuit turn percentage of the generator rotor winding to obtain the P-Q curve change rate of the generator after different turn-to-turn short circuits, and recording the change rate as mu-m-mu₁,μ₂,μ₃,…,μ_N}; wherein, each turn-to-turn short circuit percentage corresponds to the P-Q curve change rate of the generator after one turn-to-turn short circuit.

As one improvement of the above technical solution, the time interval T is 0.04 s.

The invention also provides a generator operation control method with rotor turn-to-turn short circuit fault operation, which comprises the following steps:

step S1, acquiring exciting current data of an exciting winding when the turbonator operates by using a data acquisition module at each time interval T; wherein the time interval T is 0.04 s; the excitation current data includes: a measured value of an excitation current;

step S2, calculating the change rate of the generator exciting current in the time interval T by using the exciting current data of the exciting winding obtained in the step S1 when the turbonator runs through a data analysis processing module;

step S3, judging the calculated change rate of the generator exciting current by using a judging module;

if the calculated exciting current change rate is greater than the exciting current deviation rate set value &, outputting a turn-to-turn short circuit operation state fault signal, and performing the next step S4;

if the calculated exciting current change rate is less than or equal to the exciting current deviation rate set value &, outputting a normal operating state signal;

step S4, when the turn-to-turn short circuit operation state fault signal is output, the data analysis processing module is used for calculating the turn-to-turn short circuit percentage, and the turn percentage of the short circuit is used as the severity index of the turn-to-turn short circuit fault;

step S5, according to the different turn-to-turn short circuit percentages obtained through calculation, consulting the generator rotor winding short circuit turn percentage P-Q operation limit change rate comparison table to obtain the different turn-to-turn short circuit generator P-Q curve change rates, and recording as mu- { mu ═ mu [ [ the percentage of the short circuit between the two turns of the generator₁,μ₂,μ₃,…,μ_N}；

And step S6, generating a generator operation limit diagram with mu times of reduced operation of turn-to-turn short circuit faults according to a scale reduction method through a data drawing module.

As an improvement of the above technical solution, the method further includes: and the fault processing module takes the percentage of the number of short circuit turns as the severity index of turn-to-turn short circuit faults, and processes the turn-to-turn short circuit faults in real time on line according to the severity index of the turn-to-turn short circuit faults and the drawn running limit diagram of the generator with the turn-to-turn short circuit faults running reduced by mu times, so that the normal running of a power plant is ensured.

As one improvement of the above technical solution, the step S2 specifically includes:

calculating the change rate of the excitation current of the generator within a time interval T according to the obtained excitation current data of the excitation winding when the turbonator operates;

wherein, a_nThe change rate of the generator exciting current in a time interval T;is T_nExciting current data of an exciting winding when the turbonator operates at any moment;is T_n+1Exciting current data of an exciting winding when the turbonator operates at any moment;

as one improvement of the above technical solution, the step S5 specifically includes:

when a turn-to-turn short circuit operation state fault signal is output, calculating a turn-to-turn short circuit percentage k by using a data analysis processing module;

wherein, Delta N is the number of turns of the rotor winding with turn-to-turn short circuit at the moment T; n is the number of turns of the rotor winding;the measured value of the exciting current of the excitation winding of the turbonator at the moment T;the measured value is the exciting current value of the exciting winding when the turbonator does not generate turn-to-turn short circuit;

and obtaining different turn-to-turn short circuit percentages k ═ k according to calculation₁,k₂,k₃,…,k_NLooking up a comparison table of the P-Q operation limit change rate of the short-circuit turn percentage of the generator rotor winding to obtain the P-Q curve change rate of the generator after different turn-to-turn short circuits, and recording the change rate as mu-m-mu₁,μ₂,μ₃,…,μ_N}。

Compared with the prior art, the invention has the following effects:

the system can visually find out whether the running state of the generator at each moment has turn-to-turn short circuit fault or not when the generator runs, and can clearly and accurately judge the running state of the generator at each moment; the diagnosis sensitivity is greatly improved, the popularization rate is high, the universality is good, the working efficiency is high, the diagnosis can be carried out in a shutdown environment, and faults can be found in time.

Drawings

FIG. 1 is a flow chart of a method for controlling the operation of a generator with inter-turn short circuit fault operation of a rotor according to the present invention;

FIG. 2 is a graph of P-Q of the generator after a turn-to-turn short circuit plotted in the method of FIG. 1.

Detailed Description

The invention will now be further described with reference to the accompanying drawings and examples.

The invention provides a generator operation control system considering turn-to-turn short circuit fault operation of a belt rotor, which comprises: the device comprises a data acquisition module, a data analysis processing module, a judgment module and a drawing module;

the data acquisition module is used for acquiring exciting current data of an exciting winding when the turbonator operates at each time interval T;

the data analysis processing module is used for calculating the change rate of the excitation current of the generator within a time interval T by using the obtained excitation current data of the excitation winding when the turbonator runs;

the turn-to-turn short circuit monitoring device is also used for calculating the turn-to-turn short circuit percentage by using the data analysis processing module when outputting a turn-to-turn short circuit operation state fault signal, and looking up a P-Q operation limit change rate comparison table of the short circuit turn percentage of the generator rotor winding according to different turn-to-turn short circuit percentages obtained by calculation to obtain different turn-to-turn short circuit back generator P-Q curve change rates;

specifically, the data analysis processing module includes: the device comprises a reading unit, a first analysis processing unit and a second analysis processing unit;

the reading unit is used for acquiring the excitation current data of the excitation winding when the turbonator operates;

the first analysis processing unit is used for calculating the change rate of the excitation current of the generator within a time interval T according to the obtained excitation current data of the excitation winding when the turbonator runs;

wherein, a_nThe change rate of the generator exciting current in a time interval T;is T_nExciting current data of an exciting winding when the turbonator operates at any moment;is T_n+1Exciting current data of an exciting winding when the turbonator operates at any moment;

the second analysis processing unit is used for calculating turn-to-turn short circuit percentage k by using the data analysis processing module when outputting a turn-to-turn short circuit operation state fault signal;

wherein, Delta N is the number of turns of the rotor winding with turn-to-turn short circuit at the moment T; n is the number of turns of the rotor winding;the measured value of the exciting current of the excitation winding of the turbonator at the moment T;the measured value is the exciting current value of the exciting winding when the turbonator does not generate turn-to-turn short circuit;

and obtaining different turn-to-turn short circuit percentages k ═ k according to calculation₁,k₂,k₃,…,k_NLooking up a comparison table of the P-Q operation limit change rate of the short-circuit turn percentage of the generator rotor winding to obtain the P-Q curve change rate of the generator after different turn-to-turn short circuits, and recording the change rate as mu-m-mu₁,μ₂,μ₃,…,μ_N}; wherein, each turn-to-turn short circuit percentage corresponds to the P-Q curve change rate of the generator after one turn-to-turn short circuit.

The judging module is used for judging the calculated change rate of the generator exciting current;

if the calculated exciting current change rate is greater than the exciting current deviation rate set value &, outputting a turn-to-turn short circuit operation state fault signal, and performing the next step S4; in this example, & ═ 2%;

if the calculated exciting current change rate is less than or equal to the exciting current deviation rate set value &, outputting a normal operating state signal;

and the drawing module is used for generating a mu-time reduced generator operation limit diagram with turn-to-turn short circuit fault operation according to a scaling method.

The system further comprises: and the fault processing module is used for processing the turn-to-turn short circuit fault on line in real time according to the turn-to-turn short circuit fault severity index and the drawn generator operation limit diagram with the turn-to-turn short circuit fault operation reduced by mu times, and ensuring the normal operation of a power plant.

As shown in fig. 1, the present invention also provides a generator operation control method considering turn-to-turn short circuit fault operation of a rotor, including:

step S1, acquiring exciting current data of an exciting winding when the turbonator operates by using a data acquisition module at each time interval T; wherein the time interval T is 0.04 s; the excitation current data includes: excitation current measurement value:

step S2, calculating the change rate of the generator exciting current in the time interval T by using the exciting current data of the exciting winding obtained in the step S1 when the turbonator runs through a data analysis processing module;

in particular, the amount of the solvent to be used,

wherein, a_nThe change rate of the generator exciting current in a time interval T;is T_nExciting current data of an exciting winding when the turbonator operates at any moment;is T_n+1Exciting current data of an exciting winding when the turbonator operates at any moment;

step S3, judging the calculated change rate of the generator exciting current by using a judging module;

if the calculated exciting current change rate is greater than the exciting current deviation rate set value &, outputting a turn-to-turn short circuit operation state fault signal, and performing the next step S4;

if the calculated exciting current change rate is less than or equal to the exciting current deviation rate set value &, outputting a normal operating state signal;

step S4, when the turn-to-turn short circuit operation state fault signal is output, the data analysis processing module is used for calculating the turn-to-turn short circuit percentage, and the turn percentage of the short circuit is used as the severity index of the turn-to-turn short circuit fault;

step S5, according to the different turn-to-turn short circuit percentages obtained through calculation, consulting the generator rotor winding short circuit turn percentage P-Q operation limit change rate comparison table to obtain the different turn-to-turn short circuit generator P-Q curve change rates, and recording as mu- { mu ═ mu [ [ the percentage of the short circuit between the two turns of the generator₁,μ₂,μ₃,…,μ_N}；

Specifically, when a turn-to-turn short circuit operation state fault signal is output, calculating a turn-to-turn short circuit percentage k by using a data analysis processing module;

wherein, Delta N is the number of turns of the rotor winding with turn-to-turn short circuit at the moment T; n is the number of turns of the rotor winding;the measured value of the exciting current of the excitation winding of the turbonator at the moment T;the measured value is the exciting current value of the exciting winding when the turbonator does not generate turn-to-turn short circuit;

and obtaining different turn-to-turn short circuit percentages k ═ k according to calculation₁,k₂,k₃,…,k_NLooking up a comparison table of the P-Q operation limit change rate of the short-circuit turn percentage of the generator rotor winding to obtain the P-Q curve change rate of the generator after different turn-to-turn short circuits, and recording the change rate as mu-m-mu₁,μ₂,μ₃,…,μ_N}。

The acquisition process of the comparison table of the P-Q operation limit change rate of the short circuit turn percentage of the generator rotor winding is as follows:

step A, utilizing the relationship that the reactance of the excitation winding is in direct proportion to the square of the number of turns of the winding, and according to the following formula:

converting the above formula to the following formula:

wherein x is_fThe reactance value of the excitation winding before the turn-to-turn short circuit occurs;

calculating the reactance value of the excitation winding after the inter-turn short circuit occurs by the formula

Step B, according to a calculation formula of the direct-axis synchronous reaction reactance of the generator, calculating to obtain the direct-axis synchronous reaction reactance x of the generator_d：

Wherein the content of the first and second substances,the leakage reactance of the excitation winding is known generator parameters; x is the number of_δIs stator leakage reactance;

step C see FIG. 2, according to the formula

Drawing a voltage and current phasor diagram during the operation of the generator, and amplifying coordinate axis data in the diagramMultiplying, so as to obtain a new operation limit diagram of the generator after the turn-to-turn short circuit occurs; the figure is a generator operation limit diagram with turn-to-turn short circuit fault operation;

wherein the content of the first and second substances,marking the no-load potential for rated operation of the generator as a per unit value;is the generator terminal voltage; j is an imaginary unit;is the generator terminal current;

step D, through a data analysis processing module, according to a formula

Wherein the content of the first and second substances,the no-load potential for the actual operation of the generator;

and calculating to obtain the P-Q curve change rate of the generator after turn-to-turn short circuit.

And respectively calculating the P-Q curve change rate mu of the generator when the percentage of the number of short circuit turns in the N turns of windings is k turns by the data analysis processing device according to the steps A-D, and making the P-Q curve change rate mu into a table to obtain a comparison table of the P-Q operation limit change rate of the percentage of the number of short circuit turns of the rotor windings of the generator.

I.e. in a generator with N turns of winding, the look-up table is obtained by the following steps:

when the number of short circuit turns is 1, the change rate of the P-Q curve is calculated to be mu through the process of the step A, B, C, D₁.

When the number of short circuit turns is 2, the change rate of the P-Q curve is calculated to be mu through the process of the step A, B, C, D₂.

……

When the number of short circuit turns is N, the change rate of the P-Q curve at the time is calculated to be mu through the process of the step A, B, C, D_N.

And the number of short circuit turns and the calculated change rate mu of the P-Q curve are in one-to-one correspondence to obtain the comparison table.

And step S6, generating a generator operation limit diagram with mu times of reduced operation of turn-to-turn short circuit faults according to a scale reduction method through a data drawing module.

The method further comprises the following steps: and the fault processing module takes the percentage of the number of short circuit turns as the severity index of turn-to-turn short circuit faults, and processes the turn-to-turn short circuit faults in real time on line according to the severity index of the turn-to-turn short circuit faults and the drawn running limit diagram of the generator with the turn-to-turn short circuit faults running reduced by mu times, so that the normal running of a power plant is ensured.

Referring to FIG. 2, curve AC is the excitation winding temperature rise constraint, passing through O₁C winding point O₁The rotation is obtained, a curve BC is stator current temperature rise constraint and is obtained by rotating around a point O through OC, a curve CD is prime mover power constraint, the position of the CD is obtained through prime mover maximum power, a curve DE is generator stable operation limit and is obtained through stable operation calculation. P and Q are active power and reactive power respectively;

the PQ operation limit diagram is a relation curve diagram of active power and reactive power under the condition of steady-state operation of the unit, is one of tools for analyzing the static operation stability of the generator, and is used for expressing the operation state of the unit at a certain moment and the influence of each constraint condition on an operation point. By using fig. 2, it can be seen visually whether the running state of the generator at each moment has the turn-to-turn short circuit fault or not when the generator is running, and the running state of the generator at each moment can be clearly and accurately judged.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and are not limited. Although the present invention has been described in detail with reference to the embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.