CN107100877A - A kind of booster fan RB control methods based on booster fan system state monitoring - Google Patents
A kind of booster fan RB control methods based on booster fan system state monitoring Download PDFInfo
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- CN107100877A CN107100877A CN201710397411.2A CN201710397411A CN107100877A CN 107100877 A CN107100877 A CN 107100877A CN 201710397411 A CN201710397411 A CN 201710397411A CN 107100877 A CN107100877 A CN 107100877A
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- booster fan
- booster
- fan
- pressure
- unit
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D27/00—Control, e.g. regulation, of pumps, pumping installations or pumping systems specially adapted for elastic fluids
- F04D27/001—Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01K—STEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
- F01K13/00—General layout or general methods of operation of complete plants
- F01K13/02—Controlling, e.g. stopping or starting
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Control Of Positive-Displacement Air Blowers (AREA)
Abstract
The present invention relates to a kind of booster fan RB control methods based on booster fan system state monitoring, including：According to booster fan inlet pressure, booster fan outlet pressure and booster fan current of electric situation of change; judge whether occur the unusual service condition that booster fan does not trip but can not exerted oneself in running; when detecting unusual service condition; a series of triggering booster fan system exception RB, and carry out protection acts in time.Compared with prior art, the present invention has judges the unusual service condition that blower fan can not exert oneself when booster fan does not trip in time, and realizes unit fast cutback, the advantages of maintaining the safe and stable operation of unit.
Description
Technical field
The present invention relates to thermal technics and protection, more particularly, to a kind of based on booster fan system state monitoring
Booster fan RB control methods.
Background technology
RB (RUNBACK) in thermal power generation unit refers to that unit major pant item fault trip causes unit output to be limited
When processed, exerted oneself to adapt to equipment, maintain unit safety stable operation, control system forces unit load reducing to auxiliary still in operation
The load desired value that machine can bear, this function is otherwise known as runback.Booster fan is thermal power generation unit wind
One important auxiliary equipment of cigarette system, when booster fan fault trip, it is necessary to which the low unit load of prompt drop is to maintain unit steady
Fixed operation.
In the prior art, triggering unit booster fan RB condition is tripped for booster fan and the power of the assembling unit is exerted oneself and is more than
50% rated load.However, when there are the failures such as connecting rod between booster fan and motor is come off or shaft coupling is broken, the supercharging wind
Machine system is not exerted oneself substantially, but because booster fan does not trip, it is impossible to reach triggering unit RB condition, it is impossible to automatic to realize
The urgent load down of unit, has a strong impact on safe and stable operation of the unit under the operating mode.And in current booster blower fan RB technologies, and
Do not consider to reduce influences of the booster fan RB to combustion chamber draft by pressure fan tripping operation, and not to a variety of operation sides of booster fan
Formula carries out system consideration.
The content of the invention
It is an object of the present invention to overcome the above-mentioned drawbacks of the prior art and provide one kind is based on booster fan
The booster fan RB control methods of system state monitoring.
The purpose of the present invention can be achieved through the following technical solutions：
A kind of booster fan RB control methods based on booster fan system state monitoring, including：Entered according to booster fan
Mouth pressure, booster fan outlet pressure and booster fan current of electric situation of change, judge whether be pressurized in running
The unusual service condition that blower fan does not trip but can not exerted oneself, when detecting unusual service condition, triggers booster fan system exception RB in time,
And a series of protection acts are carried out, unit fast cutback is realized, the safe and stable operation of unit is maintained.
Described booster fan system exception operating mode detection process is as follows：
When unit bringing normally into operation, detection unit booster fan inlet pressure, booster fan outlet pressure and booster fan
Current of electric situation of change, to judge and trigger booster fan system exception RB.
Described judgement and triggering booster fan system exception RB detailed processes is as follows：
1) booster fan electric current bust to idle electric current or two booster fan current of electric deviations is more than 15% specified electricity
During stream, and booster fan inlet pressure is higher than alarming value, is delayed 5 seconds, and direct tripping current low pressure charging blower fan triggers booster fan
System exception RB；
2) booster fan inlet pressure is higher than trip value, postpones 3 seconds shunt tripping booster fans, and such as air and flue system has two superchargings
Fan operation, then shunt tripping outlet pressure and electric current low booster fan, triggering booster fan system exception RB.
When the bad quality of any booster fan motor current signal, " two booster fan outlet pressure deviations are more than for use
10% rated pressure, and booster fan inlet pressure is higher than alarming value, is delayed 5 seconds " judged；
If unit air and flue system only has a booster fan, two booster fan current of electric deviations or outlet are not considered
The judgement of pressure divergence.
During the bad quality of booster fan electric current, the low booster fan of tripping operation outlet pressure.
Booster fan inlet pressure alarming value takes the high alarming value of unit booster fan inlet pressure, booster fan inlet pressure
Trip value is determined by the high alarming value superposition setting biasing of unit booster fan inlet pressure.
A series of described protection acts of carry out are specially：
1) when unit load is more than 50% rated load before RB triggerings：
A) trip abnormal booster fan and a pressure fan, final to protect according to setting order with 5s intervals tripping operation coal pulverizer
Stay 3 coal pulverizer operations；
If b) there is two booster fan operations before unit air and flue system RB, the booster fan movable vane closed after tripping operation surpasses
Speed to increase normal operation booster fan movable vane aperture, increase blower fan is exerted oneself, and override control puts into booster fan entrance pressure after terminating
Power is automatically controlled；If unit air and flue system is only equipped with a booster fan, by the booster fan movable vane standard-sized sheet after tripping operation, and entirely
Open booster fan bypass door
C) boiler master output is set to 50% boiler load；
2) when unit load is less than 50% rated load before RB triggerings：
A) trip abnormal booster fan and a pressure fan, if there is two booster fan operations before unit air and flue system RB,
The booster fan movable vane then closed after tripping operation, the normal operation booster fan movable vane aperture of override increase, increase blower fan is exerted oneself, override
Input booster fan inlet pressure is automatically controlled after control terminates；, will if unit air and flue system is only equipped with a booster fan
Booster fan movable vane standard-sized sheet after tripping operation, and standard-sized sheet booster fan bypass door；
B) the corresponding boiler load of the total coal-supplying amount of coal pulverizer is run after boiler master output tracking RB.
Compared with prior art, the present invention is according to booster fan inlet pressure, booster fan outlet pressure and booster fan
Current of electric situation of change, judges whether occur the booster fan that booster fan connecting rod is come off or shaft coupling is broken in running
System exception operating mode, when detecting unusual service condition, a series of triggering booster fan system exception RB, and it is dynamic to carry out protections in time
Make, realize unit fast cutback, maintain the safe and stable operation of unit.
Brief description of the drawings
Fig. 1 is the corresponding RB flow charts that air and flue system has two booster fans；
Fig. 2 is the corresponding RB flow charts that air and flue system has a booster fan.
Embodiment
Below in conjunction with the accompanying drawing in the embodiment of the present invention, the technical scheme in the embodiment of the present invention is carried out clear, complete
Site preparation is described, it is clear that described embodiment is a part of embodiment of the present invention, rather than whole embodiments.Based on this hair
Embodiment in bright, the every other reality that those of ordinary skill in the art are obtained on the premise of creative work is not made
Example is applied, should all belong to the scope of protection of the invention.
As depicted in figs. 1 and 2, the present invention is according to booster fan inlet pressure, booster fan outlet pressure and booster fan
Current of electric situation of change, judges occur the unusual service condition that booster fan does not trip but can not exerted oneself in running, works as detection
During to unusual service condition, a series of triggering booster fan system exception RB, and carry out protection acts in time realizes that unit is quickly lightened the burden
Lotus, maintains the safe and stable operation of unit：
When unit bringing normally into operation, detection unit booster fan inlet pressure, booster fan outlet pressure and booster fan
Current of electric situation of change, judges and triggers booster fan system exception RB as follows：
1) near booster fan electric current bust to idle electric current or two booster fan current of electric deviations are more than 15% volume
Determine electric current (when the bad quality of any booster fan motor current signal, using two booster fan outlet pressure deviations to be more than
10% rated pressure is judged) (such as unit air and flue system only has a booster fan, then does not consider two booster fan motors
The judgement of current deviation or outlet pressure deviations) when, and booster fan inlet pressure is higher than alarming value, is delayed 5 seconds, directly trips
Electric current low pressure charging blower fan (during the bad quality of booster fan electric current, the low booster fan of tripping operation outlet pressure), triggering booster fan system
Exception of uniting RB；
2) booster fan inlet pressure is higher than trip value, postpones 3 seconds shunt tripping booster fans, and such as air and flue system has two superchargings
Fan operation, then shunt tripping outlet pressure and the equal low pressure charging blower fan of electric current, trigger booster fan system exception RB；
3) above-mentioned two middle booster fan inlet pressure alarming values can use the high alarming value of unit booster fan inlet pressure, increase
Pressure fan inlet pressure trip value can be determined by the high certain biasing of alarming value superposition of unit booster fan inlet pressure.
Situation is acted after booster fan system exception RB triggerings：
1) when unit load is more than 50% rated load before RB triggerings：
A) trip abnormal booster fan and a pressure fan, final to protect according to setting order with 5s intervals tripping operation coal pulverizer
Stay 3 layers of bisque；
B) as there is two booster fan operations before air and flue system RB, then the booster fan movable vane closed after tripping operation, override increases
Plus normal operation booster fan movable vane aperture, increase blower fan and exert oneself, input booster fan inlet pressure is controlled automatically after override terminates
System；Such as unit air and flue system is only equipped with a booster fan, then by the booster fan movable vane standard-sized sheet after tripping operation, and standard-sized sheet supercharging wind
Machine bypass door
C) boiler master is output as 50% boiler load.
2) when unit load is less than 50% rated load before RB triggerings：
A) trip abnormal booster fan and a pressure fan, has two booster fan operations before such as air and flue system RB, then closes
The booster fan movable vane closed after tripping operation, the normal operation booster fan movable vane aperture of override increase, increase blower fan is exerted oneself, and override terminates
Input booster fan inlet pressure is automatically controlled afterwards；Such as unit air and flue system is only equipped with a booster fan, then by after tripping operation
Booster fan movable vane standard-sized sheet, and standard-sized sheet booster fan bypass door；
B) the corresponding boiler load of the total coal-supplying amount of coal pulverizer is run after boiler master output tracking RB.
Specific embodiment
Certain 660MW unit booster fan system exception RB is implemented：
1) the unit air and flue system is bypassed equipped with a booster fan and booster fan, tracking system booster fan entrance pressure
The alarm of power height and high alarm setting booster fan inlet pressure alarming value and trip value, respectively 500Pa and 1500Pa；Coal-grinding
Machine tripping operation order is set as F-E-D-C-B；
2) according to booster fan inlet pressure, booster fan outlet pressure and booster fan current of electric situation of change, press
Following method judges and triggering booster fan system exception RB：
A) booster fan electric current bust is to idle electric current 125A or so, and booster fan inlet pressure is higher than 500Pa, delay
5 seconds, tripped booster fan, triggering booster fan system exception RB；
B) booster fan inlet pressure is higher than 1500Pa, postpones 3 seconds shunt tripping booster fans, triggers booster fan system exception
RB；
Situation is acted after booster fan system exception RB triggerings：
1) when unit load is more than 50% rated load before RB triggerings：
A) trip abnormal booster fan and pressure fan A, according to setting order with 5s intervals tripping operation coal pulverizer, finally retains 3
Layer bisque；
B) by the booster fan movable vane standard-sized sheet after tripping operation, and standard-sized sheet booster fan bypass door；
C) boiler master is output as 330MW boiler loads.
2) when unit load is less than 50% rated load before RB triggerings：
A) trip abnormal booster fan and pressure fan A, by the booster fan movable vane standard-sized sheet after tripping operation, and standard-sized sheet booster fan
Bypass door；
B) the corresponding boiler load of total coal-supplying amount of coal pulverizer is run after boiler master output tracking RB.
The foregoing is only a specific embodiment of the invention, but protection scope of the present invention is not limited thereto, any
Those familiar with the art the invention discloses technical scope in, various equivalent modifications can be readily occurred in or replaced
Change, these modifications or substitutions should be all included within the scope of the present invention.Therefore, protection scope of the present invention should be with right
It is required that protection domain be defined.
Claims (7)
1. a kind of booster fan RB control methods based on booster fan system state monitoring, it is characterised in that including：According to increasing
Pressure fan inlet pressure, booster fan outlet pressure and booster fan current of electric situation of change, judge in running whether
There is the unusual service condition that booster fan does not trip but can not exerted oneself, when detecting unusual service condition, booster fan system is triggered in time
Unite exception RB, and carries out a series of protection acts, realizes unit fast cutback, maintains the safe and stable operation of unit.
2. a kind of booster fan RB control methods based on booster fan system state monitoring according to claim 1, its
It is characterised by, described booster fan system exception operating mode detection process is as follows：
When unit bringing normally into operation, detection unit booster fan inlet pressure, booster fan outlet pressure and booster fan motor
Curent change situation, to judge and trigger booster fan system exception RB.
3. a kind of booster fan RB control methods based on booster fan system state monitoring according to claim 2, its
It is characterised by, described judgement and triggering booster fan system exception RB detailed processes is as follows：
1) when booster fan electric current bust to idle electric current or two booster fan current of electric deviations is more than 15% rated current,
And booster fan inlet pressure is higher than alarming value, it is delayed 5 seconds, direct tripping current low pressure charging blower fan triggers booster fan system
Abnormal RB；
2) booster fan inlet pressure is higher than trip value, postpones 3 seconds shunt tripping booster fans, and such as air and flue system has two booster fans
Operation, then shunt tripping outlet pressure and electric current low booster fan, triggering booster fan system exception RB.
4. a kind of booster fan RB control methods based on booster fan system state monitoring according to claim 3, its
It is characterised by, when the bad quality of any booster fan motor current signal, " two booster fan outlet pressure deviations are more than for use
10% rated pressure, and booster fan inlet pressure is higher than alarming value, is delayed 5 seconds " judged；
If unit air and flue system only has a booster fan, two booster fan current of electric deviations or outlet pressure are not considered
The judgement of deviation.
5. a kind of booster fan RB control methods based on booster fan system state monitoring according to claim 3, its
It is characterised by, during the bad quality of booster fan electric current, the low booster fan of tripping operation outlet pressure.
6. a kind of booster fan RB control methods based on booster fan system state monitoring according to claim 3, its
It is characterised by, booster fan inlet pressure alarming value takes the high alarming value of unit booster fan inlet pressure, booster fan entrance pressure
Power trip value is determined by the high alarming value superposition setting biasing of unit booster fan inlet pressure.
7. a kind of booster fan RB control methods based on booster fan system state monitoring according to claim 1, its
It is characterised by, a series of described protection acts of carry out are specially：
1) when unit load is more than 50% rated load before RB triggerings：
A) trip abnormal booster fan and a pressure fan, final to retain 3 according to setting order with 5s intervals tripping operation coal pulverizer
Coal pulverizer is run；
If b) there is two booster fan operations before unit air and flue system RB, the booster fan movable vane closed after tripping operation, override increases
Plus normal operation booster fan movable vane aperture, increase blower fan and exert oneself, override control puts into booster fan inlet pressure certainly after terminating
Dynamic control；If unit air and flue system is only equipped with booster fan, by the booster fan movable vane standard-sized sheet after tripping operation, and standard-sized sheet increases
Pressure fan bypass door
C) boiler master output is set to 50% boiler load；
2) when unit load is less than 50% rated load before RB triggerings：
A) trip abnormal booster fan and a pressure fan, if there is two booster fan operations before unit air and flue system RB, closes
The booster fan movable vane closed after tripping operation, the normal operation booster fan movable vane aperture of override increase, increase blower fan is exerted oneself, override control
Booster fan inlet pressure is put into after end to automatically control；, will tripping operation if unit air and flue system is only equipped with a booster fan
Booster fan movable vane standard-sized sheet afterwards, and standard-sized sheet booster fan bypass door；
B) the corresponding boiler load of the total coal-supplying amount of coal pulverizer is run after boiler master output tracking RB.
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| CN201710397411.2A CN107100877B (en) | 2017-05-31 | 2017-05-31 | A kind of booster fan RB control methods based on booster fan system state monitoring |
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| CN201710397411.2A CN107100877B (en) | 2017-05-31 | 2017-05-31 | A kind of booster fan RB control methods based on booster fan system state monitoring |
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| CN107100877A true CN107100877A (en) | 2017-08-29 |
| CN107100877B CN107100877B (en) | 2018-08-24 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110645054A (en) * | 2018-10-18 | 2020-01-03 | 上海明华电力技术工程有限公司 | Steam turbine valve sequence switching control method suitable for unit RB working condition |
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| CN105135405A (en) * | 2015-08-17 | 2015-12-09 | 国家电网公司 | Induced draft fan RB control method of high-sodium lignite tower boiler unit |
| CN105805040A (en) * | 2014-12-30 | 2016-07-27 | 华润电力（菏泽）有限公司 | Method for triggering RB after primary air fan stalls and stall detection system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3955359A (en) * | 1973-06-20 | 1976-05-11 | Westinghouse Electric Corporation | Bearing temperature system failure detection apparatus suitable for use in power plants and like apparatus |
| EP2042743B1 (en) * | 2007-09-27 | 2014-11-05 | ABB Research Ltd. | A gas compression system and a method for controlling a gas compression system. |
| CN101650021A (en) * | 2009-08-25 | 2010-02-17 | 广州粤能电力科技开发有限公司 | Primary air fan tripping set run back control method and system |
| US20110158786A1 (en) * | 2009-12-30 | 2011-06-30 | General Electric Company | Method for operating steam turbine with transient elevated back pressure |
| CN102591201A (en) * | 2012-02-09 | 2012-07-18 | 山东电力研究院 | Control method of integral saturation resistance in auxiliary machine failure load reduction process |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110645054A (en) * | 2018-10-18 | 2020-01-03 | 上海明华电力技术工程有限公司 | Steam turbine valve sequence switching control method suitable for unit RB working condition |
| CN110645054B (en) * | 2018-10-18 | 2022-07-01 | 上海明华电力科技有限公司 | Steam turbine valve sequence switching control method suitable for RB working condition of unit |
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| Publication number | Publication date |
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| CN107100877B (en) | 2018-08-24 |
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