阅读说明：本技术 一种火电厂发电机组运行故障处理方法及系统 (Method and system for processing operation fault of power generating unit of thermal power plant ) 是由 田颖东 邹毅辉 易晓坚 陈超 刘丹 伍志文 于 2021-07-23 设计创作，主要内容包括：一种火电厂发电机组运行故障处理方法及系统,火电厂发电机组运行故障处理方法包括：获取故障控制信号,故障控制信号对应有多种不同的故障工况,多种故障工况具有不同的控制参数组；依据故障控制信号确认对应的故障工况；依据与已确认故障工况对应的控制参数组控制汽轮机、发电机、电网的运行,以使得汽轮机的热负荷降低至预设的热负荷比例阈值、发电机和汽轮机不出现停机。本发明通过针对不同的故障工况利用相应的控制参数组控制火力发电机组运行,使得在故障发生时火力发电机组不会直接停机,而是会通过降低汽轮机热负荷以及控制发电机分离负荷等方式来维持汽轮机、发电机的稳定运行,从而可以让整个火力发电机组尽快的恢复到可并网状态。(A method and a system for processing the operation fault of a generator set of a thermal power plant are provided, wherein the method for processing the operation fault of the generator set of the thermal power plant comprises the following steps: acquiring a fault control signal, wherein the fault control signal corresponds to multiple different fault working conditions, and the multiple fault working conditions have different control parameter sets; confirming a corresponding fault working condition according to the fault control signal; and controlling the operation of the steam turbine, the generator and the power grid according to the control parameter group corresponding to the confirmed fault working condition so as to reduce the heat load of the steam turbine to a preset heat load proportion threshold value and prevent the generator and the steam turbine from stopping. The invention controls the thermal generator set to operate by utilizing the corresponding control parameter group aiming at different fault conditions, so that the thermal generator set cannot be directly stopped when a fault occurs, and the stable operation of the steam turbine and the generator can be maintained by reducing the thermal load of the steam turbine, controlling the separation load of the generator and the like, thereby the whole thermal generator set can be recovered to a grid-connected state as soon as possible.)

1. A method for processing the operation fault of a generator set of a thermal power plant is characterized by comprising the following steps:

acquiring a fault control signal; the fault control signal corresponds to a plurality of different fault working conditions, and the plurality of fault working conditions have different control parameter sets;

confirming the corresponding fault working condition according to the fault control signal;

and controlling the operation of a steam turbine, a generator and a power grid according to the control parameter group corresponding to the confirmed fault working condition so as to reduce the heat load of the steam turbine to a preset heat load proportion threshold value and prevent the generator and the steam turbine from being shut down.

2. The method for processing the operation fault of the generator set of the thermal power plant according to claim 1, wherein the plurality of fault conditions at least comprise a power grid fault condition, a generator fault condition and a turbine fault condition, and the power grid fault condition, the generator fault condition and the turbine fault condition respectively correspond to different control parameter sets.

3. The method for processing the operation fault of the generator set of the thermal power plant as claimed in claim 2, wherein the fault condition is determined to be the grid fault condition, and the operation of the steam turbine, the generator and the grid is controlled according to the control parameter group corresponding to the determined fault condition, comprising the following steps:

disconnecting a high side switch between a main transformer and the grid to disconnect the generator from a load in the grid;

and opening a bypass valve bank and a pressure relief valve bank in a thermodynamic system of the steam turbine, and stopping N coal mills to reduce the heat load of the steam turbine to a heat load proportion threshold, wherein M coal mills are provided, and M is greater than N.

4. The method for processing the operation fault of the generator set of the thermal power plant as claimed in claim 2, wherein the fault condition is determined to be the fault condition of the generator, and the operation of the steam turbine, the generator and the power grid is controlled according to the control parameter group corresponding to the determined fault condition, comprising the following steps:

opening an output side switch of the generator to enable the generator to run in an idle state;

opening a bypass valve group and a pressure relief valve group in a thermodynamic system of the steam turbine, and stopping N coal mills, so that the heat load of the steam turbine is reduced to a heat load proportion threshold value, the rotating speed of the steam turbine is kept at a preset first standby rotating speed value, the number of the coal mills is M, and M is greater than N.

5. The method for processing the operation fault of the generator set of the thermal power plant according to claim 2, wherein the fault condition is determined to be the fault condition of the steam turbine, and the operation of the steam turbine, the generator and the power grid is controlled according to the control parameter group corresponding to the determined fault condition, comprising the following steps:

opening an output side switch of the generator to enable the generator to run in an idle state;

and opening a bypass valve group and a pressure relief valve group in a thermodynamic system of the steam turbine, and stopping N coal mills, so that the heat load of the steam turbine is reduced to the heat load proportion threshold value, the rotating speed of the steam turbine is recovered to a preset second standby rotating speed value and is kept, wherein M coal mills are provided, and M is greater than N.

6. The method for processing the operation fault of the generator set of the thermal power plant according to claim 1, wherein the fault control signal at least comprises a grid fault control signal, a generator fault control signal and a turbine fault control signal, wherein the grid fault control signal is generated when an output side switch of the generator is turned off, the grid fault control signal is generated by receiving grid fault information sent by a grid monitoring device, and the turbine fault control signal is generated by receiving a turbine trip signal sent by a control system of the turbine.

7. The method for processing the operation fault of the generator set of the thermal power plant as claimed in claim 1, wherein if the steam turbine cannot provide enough steam to drive the operation of the steam feed pump, the method for processing the operation fault of the generator set of the thermal power plant further comprises the following steps:

stopping supplying steam to the steam-driven water-feeding pump by using steam in the steam turbine;

controlling a reheater to directly output high-pressure steam to drive the steam-driven water-feeding pump;

controlling the auxiliary steam header to output low-pressure steam to drive the steam-driven water feeding pump;

and gradually reducing the high-pressure steam directly output to the steam-driven feed water pump by the reheater according to the rotating speed value of the steam-driven feed water pump, so that the steam-driven feed water pump stably operates only under the driving of the low-pressure steam.

8. An operation fault handling system for a generator set of a thermal power plant, comprising:

the fault signal acquisition module is used for acquiring a fault control signal; the fault control signal corresponds to a plurality of different fault working conditions, and the plurality of fault working conditions have different control parameter sets;

the working condition confirming module is used for confirming the corresponding fault working condition according to the fault control signal;

and the unit operation control module is used for controlling the operation of the steam turbine, the generator and the power grid according to the control parameter group corresponding to the confirmed fault working condition so as to reduce the heat load of the steam turbine to a preset heat load proportion threshold value and prevent the generator and the steam turbine from stopping.

9. The thermal power plant generator set operation fault handling system of claim 8, wherein the plurality of fault conditions include at least a grid fault condition, a generator fault condition, and a turbine fault condition, and the grid fault condition, the generator fault condition, and the turbine fault condition correspond to different sets of the control parameters, respectively.

10. The thermal power plant generator set operation fault handling system of claim 8, further comprising an emergency steam supply control module, wherein the emergency steam supply control module is configured to control a reheater to output high pressure steam and an auxiliary steam header to output low pressure steam to drive the steam feed pump to operate when the steam turbine fails to provide enough steam to drive the steam feed pump to operate.

Technical Field

The invention belongs to the field of generating sets of thermal power plants, and particularly relates to a method and a system for processing operation faults of generating sets of thermal power plants.

Background

With the construction of large power plants and extra-high voltage power grids in China accelerating, more and more power equipment are provided, and the number of thermal power generating units is increased as one of main power sources. However, with the increase of the number of thermal power generating units, the problems are increased, the fault conditions are more and more old, and after serious fault conditions such as load shedding and tripping of a steam turbine occur, the whole unit is stopped. However, the time from the shutdown of the thermal generator set to the restart of the grid-belt loading is more than 4 hours, the actual benefit of the generator set is seriously lost, and even part of system equipment fails due to sudden high-load shutdown, so that the shutdown time of the whole generator set is longer.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the invention provides a thermal power plant generator set operation fault processing method, which solves the problem that a thermal generator set can directly cause unit shutdown when part of major fault working conditions occur. The invention further provides a system for processing the operation fault of the generator set of the thermal power plant.

According to the embodiment of the first aspect of the invention, the method for processing the operation fault of the generating set of the thermal power plant comprises the following steps:

acquiring a fault control signal; the fault control signal corresponds to a plurality of different fault working conditions, and the plurality of fault working conditions have different control parameter sets;

confirming the corresponding fault working condition according to the fault control signal;

and controlling the operation of a steam turbine, a generator and a power grid according to the control parameter group corresponding to the confirmed fault working condition so as to reduce the heat load of the steam turbine to a preset heat load proportion threshold value and prevent the generator and the steam turbine from being shut down.

The method for processing the operation fault of the generator set of the thermal power plant, provided by the embodiment of the invention, at least has the following technical effects: the thermal power generator set is controlled to operate by confirming specific fault conditions of the thermal power generator set and utilizing corresponding control parameter sets according to different fault conditions, so that the thermal power generator set cannot be directly stopped when a fault occurs, and the stable operation of a steam turbine and a generator can be maintained by reducing the thermal load of the steam turbine and controlling the separation load of the generator and the like. The method for processing the operation fault of the thermal power generating unit can effectively maintain the operation stability of the thermal power generating unit when the fault occurs, and ensure that a steam turbine and a generator cannot be directly stopped, thereby enabling the whole thermal power generating unit to be recovered to a grid-connectable state as soon as possible.

According to some embodiments of the present invention, the plurality of fault conditions at least include a power grid fault condition, a generator fault condition, and a turbine fault condition, and the power grid fault condition, the generator fault condition, and the turbine fault condition respectively correspond to different sets of the control parameters.

According to some embodiments of the present invention, determining that the fault condition is the grid fault condition, and controlling the operation of the steam turbine, the generator, and the grid according to the control parameter group corresponding to the determined fault condition includes:

disconnecting a high side switch between a main transformer and the grid to disconnect the generator from a load in the grid;

and opening a bypass valve bank and a pressure relief valve bank in a thermodynamic system of the steam turbine, and stopping N coal mills to reduce the heat load of the steam turbine to a heat load proportion threshold, wherein M coal mills are provided, and M is greater than N.

According to some embodiments of the present invention, determining that the fault condition is the generator fault condition, and controlling the operation of the steam turbine, the generator and the power grid according to the control parameter group corresponding to the determined fault condition comprises the following steps:

opening an output side switch of the generator to enable the generator to run in an idle state;

opening a bypass valve group and a pressure relief valve group in a thermodynamic system of the steam turbine, and stopping N coal mills, so that the heat load of the steam turbine is reduced to a heat load proportion threshold value, the rotating speed of the steam turbine is kept at a preset first standby rotating speed value, the number of the coal mills is M, and M is greater than N.

According to some embodiments of the present invention, determining that the fault condition is the turbine fault condition, and controlling the operation of the turbine, the generator, and the power grid according to the control parameter group corresponding to the determined fault condition includes:

opening an output side switch of the generator to enable the generator to run in an idle state;

and opening a bypass valve group and a pressure relief valve group in a thermodynamic system of the steam turbine, and stopping N coal mills, so that the heat load of the steam turbine is reduced to the heat load proportion threshold value, the rotating speed of the steam turbine is recovered to a preset second standby rotating speed value and is kept, wherein M coal mills are provided, and M is greater than N.

According to some embodiments of the present invention, the fault control signal includes at least a grid fault control signal, a generator fault control signal, and a turbine fault control signal, wherein the grid fault control signal is generated when an output side switch of the generator is turned off, the grid fault control signal is generated by receiving grid fault information sent by a grid monitoring device, and the turbine fault control signal is generated by receiving a turbine trip signal sent by a control system of the turbine.

According to some embodiments of the present invention, if the steam turbine cannot provide enough steam to drive the operation of the steam feed pump, the method for processing the operation fault of the power plant generating set further comprises the following steps:

stopping supplying steam to the steam-driven water-feeding pump by using steam in the steam turbine;

controlling a reheater to directly output high-pressure steam to drive the steam-driven water-feeding pump;

controlling the auxiliary steam header to output low-pressure steam to drive the steam-driven water feeding pump;

and gradually reducing the high-pressure steam directly output to the steam-driven feed water pump by the reheater according to the rotating speed value of the steam-driven feed water pump, so that the steam-driven feed water pump stably operates only under the driving of the low-pressure steam.

According to the embodiment of the second aspect of the invention, the system for processing the operation fault of the generating set of the thermal power plant comprises:

the fault signal acquisition module is used for acquiring a fault control signal; the fault control signal corresponds to a plurality of different fault working conditions, and the plurality of fault working conditions have different control parameter sets;

the working condition confirming module is used for confirming the corresponding fault working condition according to the fault control signal;

and the unit operation control module is used for controlling the operation of the steam turbine, the generator and the power grid according to the control parameter group corresponding to the confirmed fault working condition so as to reduce the heat load of the steam turbine to a preset heat load proportion threshold value and prevent the generator and the steam turbine from stopping.

The thermal power plant generator set operation fault processing system provided by the embodiment of the invention at least has the following technical effects: the specific fault working condition of the thermal power generator unit is confirmed through the fault signal acquisition module and the working condition confirmation module, and then the unit operation control module controls the thermal power generator unit to operate according to different fault working conditions by utilizing corresponding control parameter sets, so that the thermal power generator unit cannot be directly stopped when a fault occurs, and the stable operation of a steam turbine and a generator can be maintained by reducing the thermal load of the steam turbine, controlling the separation load of the generator and the like. The method for processing the operation fault of the thermal power generating unit can effectively maintain the operation stability of the thermal power generating unit when the fault occurs, and ensure that a steam turbine and a generator cannot be directly stopped, thereby enabling the whole thermal power generating unit to be recovered to a grid-connectable state as soon as possible.

According to some embodiments of the present invention, the plurality of fault conditions at least include a power grid fault condition, a generator fault condition, and a turbine fault condition, and the power grid fault condition, the generator fault condition, and the turbine fault condition respectively correspond to different sets of the control parameters.

According to some embodiments of the invention, the system for processing the operation fault of the generator set of the thermal power plant further comprises an emergency steam supply control module, wherein the emergency steam supply control module is used for controlling the reheater to output high-pressure steam and the auxiliary steam header to output low-pressure steam to drive the steam feed pump to operate when the steam turbine cannot provide enough steam to drive the steam feed pump to operate.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a simplified flow diagram of a method for handling operational faults of a power generating unit of a thermal power plant in accordance with an embodiment of the present invention;

FIG. 2 is a block diagram of a system for processing operating faults of a power generating unit of a thermal power plant according to an embodiment of the invention;

FIG. 3 is a system diagram of a turbine thermodynamic system;

FIG. 4 is a system schematic of a feedwater pump drive system;

FIG. 5 is a system diagram of a fume system;

fig. 6 is a system diagram of a power distribution system.

Reference numerals:

an output side switch 110, a high voltage side switch 120,

A high pressure cylinder 210, an intermediate pressure cylinder 220, a low pressure cylinder 230, a condenser 240, a pressure relief valve set 250, a first bypass valve 261, a second bypass valve 262,

The four-extraction steam inlet valve 310, the main steam valve 320, the low-pressure regulating valve 330, the cold-end steam inlet valve 340, the high-pressure regulating valve 350 and the auxiliary steam inlet valve 360.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the directional descriptions, such as the directions of upper, lower, front, rear, left, right, etc., are referred to only for convenience of describing the present invention and for simplicity of description, and are not intended to indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

In the description of the present invention, the meaning of a plurality of means is one or more, the meaning of a plurality of means is two or more, and larger, smaller, larger, etc. are understood as excluding the number, and larger, smaller, inner, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless otherwise explicitly limited, terms such as arrangement, installation, connection and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present invention in combination with the specific contents of the technical solutions.

In order to better describe the thermal power plant generating set operation fault processing method according to the first aspect of the invention, a thermal power generation system for executing the thermal power plant generating set operation fault processing method according to the embodiment of the invention is provided.

Referring to fig. 3-6, there are included a power distribution system, a flue system, a turbine thermal system, and a feed pump drive system.

Referring to fig. 6, in the power distribution system, the generator is used for generating power, an output side switch 110 is disposed on an output side of the generator, and the generator is respectively connected to an auxiliary transformer and a main transformer through the output side switch 110, the auxiliary transformer is used for supplying power to equipment in an auxiliary plant, and the main transformer is connected to a power grid bus through a high-voltage side switch 120 to supply power to a load in a power grid. Here, a main transformer and two service transformers are provided.

Referring to fig. 5, in the wind smoke system, 6 coal mills are provided, and coal ground by the 6 coal mills is combusted with the aid of the wind smoke system to generate enough heat energy for a boiler or other equipment needing heating in a turbine thermodynamic system.

Referring to fig. 3, in a steam turbine thermodynamic system, a steam feed water pump in a water supply system supplies water to an economizer and a superheater, and then superheated steam (high-pressure steam) is generated by the economizer and the superheater, which needs to be described herein that the economizer can use heat of flue tail gas to heat the water. After the superheated steam is generated, the superheated steam is output to the high pressure cylinder 210 of the turbine, then input to the reheater, then input from the reheater to the intermediate pressure cylinder 220 and the low pressure cylinder 230 of the turbine, finally enter the condenser 240 to be changed into water again, and then wait for the steam to be converted into steam from the economizer and the superheater. Here, a pressure relief valve group 250 is provided on the boiler side (i.e., on the side where the superheater is located) for pressure relief, a first bypass valve 261 is provided on the turbine high pressure cylinder 210 side, a second bypass valve 262 is provided between the reheater outlet and the condenser 240, and the first bypass valve 261 and the second bypass valve 262 are bypass valve groups. When the bypass valve set and the pressure relief valve set 250 are opened, the pressure in the steam turbine can be quickly relieved.

Referring to fig. 4, in the feed water pump driving system, a steam feed water pump is normally driven by using steam (i.e., four-extraction steam) in the turbine intermediate pressure cylinder 220 to supply water to the turbine thermal system, and in fig. 4, the four-extraction steam passes through a four-extraction steam inlet valve 310 and then is sequentially supplied to the steam feed water pump through a main steam valve 320 and a low pressure regulating valve 330. In fig. 4, the reheater cold-end steam is superheated steam, and is output by the reheater, and reaches the main steam valve 320 through the cold-end steam admission valve 340 and the high-pressure regulating valve 350. In fig. 4, the auxiliary steam is low-pressure steam, which is output from the reheater through the auxiliary steam header and reaches the main steam valve 320 through the auxiliary steam inlet valve 360.

The thermal power generation system and the application scenario described in the embodiment of the present invention are for more clearly illustrating the technical solution of the embodiment of the present invention, and do not limit the technical solution provided in the embodiment of the present invention, and it can be known by those skilled in the art that the technical solution provided in the embodiment of the present invention is also applicable to similar technical problems along with the evolution of the thermal power generation system technology and the occurrence of new application scenarios.

An operating fault handling method for a thermal power plant generator set according to an embodiment of the first aspect of the invention is described below with reference to fig. 1 to 6.

The method for processing the operation fault of the generator set of the thermal power plant comprises the following steps:

acquiring a fault control signal; the fault control signal corresponds to a plurality of different fault working conditions, and the plurality of fault working conditions have different control parameter sets;

confirming a corresponding fault working condition according to the fault control signal;

and controlling the operation of the steam turbine, the generator and the power grid according to the control parameter group corresponding to the confirmed fault working condition so as to reduce the heat load of the steam turbine to a preset heat load proportion threshold value and prevent the generator and the steam turbine from stopping.

Referring to fig. 1 to 6, the fault control signal includes a plurality of different control signals, which respectively correspond to a plurality of different fault conditions. When the fault condition happens, a corresponding fault control signal can be generated, and then the specific fault condition after the fault control signal is received can be confirmed, then the steam turbine, the generator and the power grid are controlled by utilizing the control parameter set which is set in advance and stored, namely, the heat load of the steam turbine is quickly reduced to an expected heat load proportion threshold value by controlling the operation state of a power distribution system, a wind and smoke system, a steam turbine thermodynamic system and a water supply pump driving system, so that the steam turbine cannot be directly shut down, the output load of the generator can be reduced, the generator cannot be shut down and can be stably operated, meanwhile, along with the reduction of the output load of the generator, the required output power of the steam turbine is smaller, and the heat load can be reduced more quickly and more stably. Therefore, the heat load of the steam turbine and the output load of the generator are effectively reduced by controlling the power distribution system, the air and smoke system, the thermal system of the steam turbine and the water feeding pump driving system, so that the steam turbine and the generator can be quickly stabilized again, and after a follow-up operator confirms that the whole thermal generator set is free of faults, the steam turbine and the generator can be quickly put into grid connection again.

According to the method for processing the operation fault of the generator unit of the thermal power plant, the thermal generator unit is controlled to operate by confirming the specific fault working condition of the thermal generator unit and utilizing the corresponding control parameter group according to different fault working conditions, so that the thermal generator unit cannot be directly stopped when a fault occurs, and the stable operation of a steam turbine and a generator can be maintained by reducing the thermal load of the steam turbine, controlling the separation load of the generator and the like. The method for processing the operation fault of the thermal power generating unit can effectively maintain the operation stability of the thermal power generating unit when the fault occurs, and ensure that a steam turbine and a generator cannot be directly stopped, thereby enabling the whole thermal power generating unit to be recovered to a grid-connectable state as soon as possible.

In some embodiments of the present invention, the plurality of fault conditions at least include a power grid fault condition, a generator fault condition, and a turbine fault condition, and the power grid fault condition, the generator fault condition, and the turbine fault condition respectively correspond to different sets of control parameters. The method mainly comprises the steps that a plurality of fault conditions are provided, a power grid fault condition is mainly set for a fault of a power grid needing to be separated, a generator fault condition is set for a fault of a generator output side switch 110 needing to be disconnected, a turbine fault condition is set for turbine tripping, and a corresponding control parameter set is set for a control process needing to be executed under each fault condition for control. The control parameter set is mainly used for controlling valve members, switches and the like in a power distribution system, a wind and smoke system, a turbine thermodynamic system and a water supply pump driving system.

It should be noted that the thermal load ratio threshold needs to be set according to the thermal load of the turbine, the load of the generator and the usage requirements of the peripheral system, and in some embodiments, the thermal load ratio threshold is set at fifty percent, which is enough to meet the requirements in most cases.

In some embodiments of the present invention, determining that the fault condition is a grid fault condition, and controlling the operation of the steam turbine, the generator, and the grid according to the control parameter group corresponding to the determined fault condition includes the following steps:

disconnecting the high side switch 120 between the main transformer and the grid to disconnect the generator from the load in the grid;

and opening a bypass valve set and a pressure relief valve set 250 in a thermodynamic system of the steam turbine, and stopping N coal mills to reduce the heat load of the steam turbine to a heat load proportion threshold, wherein M coal mills are provided, and M is greater than N.

After the grid fault condition is determined, the corresponding control parameter set is executed, at this time, the high-voltage side switch 120 between the main transformer and the grid is disconnected, the load of the generator is reduced, and the generator and the steam turbine are prevented from being directly stopped by high load. Because the fault is in the power grid, the generator can carry plant equipment to perform isolated island operation without separating the plant transformer. After the sudden unloading of the load of the generator, the heat load of the steam turbine needs to be reduced as soon as possible, so that the running state adaptation of the steam turbine and the generator is ensured, a bypass valve group in a thermodynamic system is opened, superheated steam can be quickly released by a pressure release valve group 250, the heat load is quickly reduced, meanwhile, N coal mills can be stopped, an air smoke system can be automatically adjusted, the input of heat energy in the thermodynamic system of the steam turbine is reduced, the heat load of the steam turbine can be quickly reduced to a heat load proportion threshold value, and the stable running of the steam turbine and the generator is ensured. The specific number of the stopped coal mills can be properly adjusted according to actual conditions. In some embodiments of the invention, there are 6 coal mills, and the service requirement of the steam turbine can be well assisted by stopping 3 coal mills.

In some embodiments of the present invention, determining that the fault condition is a generator fault condition, and controlling the operation of the steam turbine, the generator, and the power grid according to the control parameter group corresponding to the determined fault condition includes the following steps:

the output side switch 110 of the generator is opened to allow the generator to run idle;

opening a bypass valve set and a pressure relief valve set 250 in a thermodynamic system of the steam turbine, and stopping N coal mills to reduce the heat load of the steam turbine to a heat load proportion threshold value and keep the rotating speed of the steam turbine at a preset first standby rotating speed value, wherein M coal mills are provided, and M is greater than N.

After the working condition of the generator fault is determined, the corresponding control parameter set is executed, at this time, the output side switch 110 of the generator is firstly switched off, the generator is in an idle state, and the generator and the steam turbine are prevented from being directly stopped under a high load. After the sudden unloading of the load of the generator, the heat load of the steam turbine needs to be reduced as soon as possible, so that the running state adaptation of the steam turbine and the generator is ensured, a bypass valve group in a thermodynamic system is opened, superheated steam can be quickly released by a pressure release valve group 250, the heat load is quickly reduced, meanwhile, N coal mills can be stopped, an air smoke system can be automatically adjusted, the input of heat energy in the thermodynamic system of the steam turbine is reduced, the heat load of the steam turbine can be quickly reduced to a heat load proportion threshold value, and the stable running of the steam turbine and the generator is ensured. At this time, because the generator is in an idling state, the steam turbine needs to be maintained at the first standby rotating speed value, so that the whole generator set can be recovered to a grid-connected state as soon as possible. In some embodiments of the invention, the turbine may be maintained at 3000 rpm. The specific number of the stopped coal mills can be properly adjusted according to actual conditions. In some embodiments of the invention, there are 6 coal mills, and the service requirement of the steam turbine can be well assisted by stopping 3 coal mills. In addition, in an actual situation, when a generator fault condition or a turbine fault condition occurs, the output side switch 110 is turned off, the high-voltage side switch 120 is not turned off, service power is sent back from the main transformer, and after the fault is eliminated, the output side switch 110 is directly turned on to perform system grid connection.

In some embodiments of the present invention, determining that the fault condition is a turbine fault condition, and controlling the operation of the turbine, the generator, and the grid according to the set of control parameters corresponding to the determined fault condition includes the following steps:

the output side switch 110 of the generator is opened to allow the generator to run idle;

and opening a bypass valve set and a pressure relief valve set 250 in a thermodynamic system of the steam turbine, and stopping N coal mills to reduce the heat load of the steam turbine to a heat load proportion threshold value, and recovering the rotating speed of the steam turbine to a preset second standby rotating speed value and keeping the rotating speed, wherein M coal mills are provided, and M is greater than N.

When the working condition of the steam turbine fault is determined, the corresponding control parameter set is executed, at this time, the output side switch 110 of the generator is firstly switched off, the generator is in an idle state, and the generator and the steam turbine are prevented from being directly stopped under a high load. After the sudden unloading of the load of the generator, the heat load of the steam turbine needs to be reduced as soon as possible, so as to ensure the stable operation of the steam turbine and the generator, the bypass valve bank in the thermodynamic system is opened, the pressure relief valve bank 250 can quickly release superheated steam, the heat load is quickly reduced, meanwhile, N coal mills can be stopped, the air smoke system can be automatically adjusted, the input of heat energy in the thermodynamic system of the steam turbine is reduced, the heat load of the steam turbine can be quickly reduced to a heat load proportion threshold value, and the stable operation of the steam turbine and the generator is ensured. Meanwhile, because of the occurrence of a steam turbine fault working condition, the steam turbine is in a trip state, and the rotating speed of the steam turbine needs to be rapidly rushed to a second standby rotating speed value after the thermal load of the steam turbine is reduced so as to ensure the normal operation of the generator and further ensure that the whole generator set can be rapidly recovered to a grid-connected state. In some embodiments of the present invention, the second standby rotational speed value may be set to 3000 revolutions per minute. The specific number of the stopped coal mills can be properly adjusted according to actual conditions. In some embodiments of the invention, there are 6 coal mills, and the service requirement of the steam turbine can be well assisted by stopping 3 coal mills. In addition, in actual conditions, after the thermal generator set recovers stable operation under the working condition of steam turbine fault, the output side switch 110 of the generator is closed firstly to bring service power to operate, so that the grid can be quickly put into connection when grid connection is needed, and the generator can be prevented from no-load operation for a long time.

In some embodiments of the present invention, the fault control signal at least includes a grid fault control signal, a generator fault control signal, and a turbine fault control signal, wherein the grid fault control signal is generated when the output side switch 110 of the generator is turned off, the grid fault control signal is generated by receiving grid fault information sent by a grid monitoring device, and the turbine fault control signal is generated by receiving a turbine trip signal sent by a control system of the turbine. The fault determination of the generator fault control signal is simple, and only the output side switch 110 of the generator needs to be segmented or not, and in actual engineering, the grid fault information can be obtained by directly communicating with a generator control system. The power grid fault needs to be confirmed in an auxiliary mode through the power grid monitoring device, the power grid monitoring device can monitor the operation of the power grid, when the power grid fails, data such as voltage and current of a power grid bus can be suddenly changed, the power grid monitoring device can generate power grid fault information, after the power grid fault information sent by the power grid monitoring device is received, the power grid fault condition can be confirmed, the high-voltage side switch 120 can be disconnected at the moment, and the power grid is separated. When the steam turbine has a tripping fault, the control system of the steam turbine can generate a tripping signal of the steam turbine, and after the tripping signal of the steam turbine is received, the working condition of the steam turbine fault can be determined. It should be noted here that the judgment of whether the turbine trips is simple, and when the turbine valve is closed and the rotation speed is reduced, the control system of the turbine can confirm that a trip fault occurs.

In some embodiments of the present invention, if the steam turbine cannot provide enough steam to drive the operation of the steam feed water pump, the method for processing the operation fault of the power generating unit in the thermal power plant further comprises the following steps:

stopping supplying steam to the steam-driven water-feeding pump by using steam in the steam turbine;

controlling a reheater to directly output high-pressure steam to drive a steam-driven water feeding pump;

controlling the auxiliary steam header to output low-pressure steam to drive the steam-driven water feeding pump;

according to the rotating speed value of the steam-driven feed water pump, high-pressure steam directly output to the steam-driven feed water pump by the reheater is gradually reduced, so that the steam-driven feed water pump can stably operate only under the driving of the low-pressure steam.

After the fault condition appears, because the heat load needs to be sharply reduced, steam pressure in a medium-pressure cylinder of the steam turbine is likely to be insufficient at the moment, and then the steam turbine cannot directly use four-pumping steam to drive the steam feed pump, and once the steam feed pump cannot operate, the whole thermodynamic system is likely to be failed, and then the steam turbine is stopped. At this time, the reheater and the auxiliary steam header of the reheater are needed to output double-path steam to ensure the normal operation of the steam feed pump.

As described with reference to fig. 3 and 4, when the pressure of the four-extraction steam is insufficient, the four-extraction steam inlet valve 310 is directly closed, so that the four-extraction steam is stopped from being used for steam supply. At this time, since the bypass valve set is closed in the reheater, high-pressure steam still exists, and then, after the cold-end steam inlet valve 340 and the high-pressure regulating valve 350 are opened, the high-pressure steam in the reheater can be input to the steam feed pump. Meanwhile, the reheater can output low-pressure steam through the auxiliary steam header, and the low-pressure steam can be input into the steam-driven water-feeding pump after the auxiliary steam inlet valve is opened. Therefore, the steam-driven water feeding pump realizes double-steam-source control through high-pressure steam and low-pressure steam. Then, the high pressure regulating valve 350 is gradually closed until finally the steam feed pump is driven to operate stably only by the low pressure steam. It should be noted that the low-pressure steam control is more stable than the high-pressure steam control, and therefore the low-pressure steam is finally used for realizing the stable control, and it is considered that the pressure shortage occurs at the moment when the four-pumping steam valve is closed, so the high-pressure steam is firstly used as the main force for driving to keep the rotating speed of the steam-driven water-feeding pump, if the high-pressure steam is continuously used for driving, the rotating speed is continuously increased to exceed the rated rotating speed of the steam-driven water-feeding pump, and therefore, the input of the high-pressure steam is gradually reduced until the low-pressure steam is finally used for keeping the operation of the steam-driven water-feeding pump.

In addition, it should be noted that after the steam turbine recovers the stable operation, the pressure in the medium-pressure cylinder of the steam turbine is certainly enough, so that the auxiliary steam inlet valve 360 cannot be directly closed and the four-extraction steam inlet valve cannot be opened, the four-extraction steam is used for driving the steam-driven water feeding pump, and the auxiliary steam inlet valve 360 cannot be closed and the four-extraction steam inlet valve cannot be opened until the load of the steam turbine increases, and the four-extraction steam is used for driving the steam-driven water feeding pump after the pressure in the medium-pressure cylinder is enough.

The thermal power plant generator set operation fault processing system comprises a fault signal acquisition module, a working condition confirmation module and a generator set operation control module.

The fault signal acquisition module is used for acquiring a fault control signal; the fault control signal corresponds to a plurality of different fault working conditions, and the plurality of fault working conditions have different control parameter sets;

the working condition confirming module is used for confirming the corresponding fault working condition according to the fault control signal;

and the unit operation control module is used for controlling the operation of the steam turbine, the generator and the power grid according to the control parameter group corresponding to the confirmed fault working condition so as to reduce the heat load of the steam turbine to a preset heat load proportion threshold value and prevent the generator and the steam turbine from stopping.

Referring to fig. 1 to 6, the fault control signal includes a plurality of different control signals, which respectively correspond to a plurality of different fault conditions. When the fault working condition occurs, the corresponding fault control signal is generated, and then the specific fault working condition can be confirmed through the working condition confirmation module after the fault control signal is received by the unit operation control module, then the unit operation control module controls the operation of the steam turbine, the generator and the power grid by utilizing the control parameter group which is set in advance and stored, namely, the heat load of the steam turbine is quickly reduced to an expected heat load proportion threshold value by controlling the running states of a power distribution system, a wind and smoke system, a steam turbine thermodynamic system and a feed pump driving system, so that the steam turbine cannot be directly stopped, meanwhile, the generator can reduce the output load, the generator can not stop and can stably run, meanwhile, along with the reduction of the output load of the generator, the power required to be output by the steam turbine is smaller, and the reduction of the heat load can be completed more quickly and stably. Therefore, the heat load of the steam turbine and the output load of the generator are effectively reduced by controlling the power distribution system, the air and smoke system, the thermal system of the steam turbine and the water feeding pump driving system, so that the steam turbine and the generator can be quickly stabilized again, and after a follow-up operator confirms that the whole thermal generator set is free of faults, the steam turbine and the generator can be quickly put into grid connection again.

The thermal power plant generator set operation fault processing system provided by the embodiment of the invention at least has the following technical effects: the specific fault working condition of the thermal power generator unit is confirmed through the fault signal acquisition module and the working condition confirmation module, and then the unit operation control module controls the thermal power generator unit to operate according to different fault working conditions by utilizing corresponding control parameter sets, so that the thermal power generator unit cannot be directly stopped when a fault occurs, and the stable operation of a steam turbine and a generator can be maintained by reducing the thermal load of the steam turbine, controlling the separation load of the generator and the like. The method for processing the operation fault of the thermal power generating unit can effectively maintain the operation stability of the thermal power generating unit when the fault occurs, and ensure that a steam turbine and a generator cannot be directly stopped, thereby enabling the whole thermal power generating unit to be recovered to a grid-connectable state as soon as possible.

In some embodiments of the present invention, the plurality of fault conditions at least include a power grid fault condition, a generator fault condition, and a turbine fault condition, and the power grid fault condition, the generator fault condition, and the turbine fault condition respectively correspond to different sets of control parameters. The method mainly comprises the steps that a plurality of fault conditions are provided, a power grid fault condition is mainly set for a fault of a power grid needing to be separated, a generator fault condition is set for a fault of a generator output side switch 110 needing to be disconnected, a turbine fault condition is set for turbine tripping, and a corresponding control parameter set is set for a control process needing to be executed under each fault condition for control. The control parameter set is mainly used for controlling valve members, switches and the like in a power distribution system, a wind and smoke system, a turbine thermodynamic system and a water supply pump driving system.

It should be noted that the thermal load ratio threshold needs to be set according to the thermal load of the turbine, the load of the generator and the usage requirements of the peripheral system, and in some embodiments, the thermal load ratio threshold is set at fifty percent, which is enough to meet the requirements in most cases.

In some embodiments of the present invention, the system for processing an operation failure of a power generating unit in a thermal power plant further includes an emergency steam supply control module, where the emergency steam supply control module is configured to control the reheater to output high-pressure steam and the auxiliary steam header to output low-pressure steam to drive the steam feed pump to operate when the steam turbine cannot provide enough steam to drive the steam feed pump to operate.

After the fault condition appears, because the heat load needs to be sharply reduced, steam pressure in a medium-pressure cylinder of the steam turbine is likely to be insufficient at the moment, and then the steam turbine cannot directly use four-pumping steam to drive the steam feed pump, and once the steam feed pump cannot operate, the whole thermodynamic system is likely to be failed, and then the steam turbine is stopped. At the moment, the emergency steam supply control module is used for controlling the reheater and the auxiliary steam header of the reheater to output double-path steam to ensure the normal operation of the steam-driven feed water pump.

As described with reference to fig. 3 and 4, when the pressure of the four-extraction steam is insufficient, the four-extraction steam inlet valve 310 is directly closed, so that the four-extraction steam is stopped from being used for steam supply. At this time, since the bypass valve set is closed in the reheater, high-pressure steam still exists, and then, after the cold-end steam inlet valve 340 and the high-pressure regulating valve 350 are opened, the high-pressure steam in the reheater can be input to the steam feed pump. Meanwhile, the reheater can output low-pressure steam through the auxiliary steam header, and the low-pressure steam can be input into the steam-driven water-feeding pump after the auxiliary steam inlet valve is opened. Therefore, the steam-driven water feeding pump realizes double-steam-source control through high-pressure steam and low-pressure steam. Then, the high pressure regulating valve 350 is gradually closed until finally the steam feed pump is driven to operate stably only by the low pressure steam. It should be noted that the low-pressure steam control is more stable than the high-pressure steam control, and therefore the low-pressure steam is finally used for realizing the stable control, and it is considered that the pressure shortage occurs at the moment when the four-pumping steam valve is closed, so the high-pressure steam is firstly used as the main force for driving to keep the rotating speed of the steam-driven water-feeding pump, if the high-pressure steam is continuously used for driving, the rotating speed is continuously increased to exceed the rated rotating speed of the steam-driven water-feeding pump, and therefore, the input of the high-pressure steam is gradually reduced until the low-pressure steam is finally used for keeping the operation of the steam-driven water-feeding pump.

In addition, it should be noted that after the steam turbine recovers the stable operation, the pressure in the medium-pressure cylinder of the steam turbine is certainly enough, so that the auxiliary steam inlet valve 360 cannot be directly closed and the four-extraction steam inlet valve cannot be opened, the four-extraction steam is used for driving the steam-driven water feeding pump, and the auxiliary steam inlet valve 360 cannot be closed and the four-extraction steam inlet valve cannot be opened until the load of the steam turbine increases, and the four-extraction steam is used for driving the steam-driven water feeding pump after the pressure in the medium-pressure cylinder is enough.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to the embodiments, and those skilled in the art will understand that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.