CN111550415B - Driving system and driving control method of steam turbine-motor driven water feeding pump - Google Patents
Driving system and driving control method of steam turbine-motor driven water feeding pump Download PDFInfo
- Publication number
- CN111550415B CN111550415B CN202010401448.XA CN202010401448A CN111550415B CN 111550415 B CN111550415 B CN 111550415B CN 202010401448 A CN202010401448 A CN 202010401448A CN 111550415 B CN111550415 B CN 111550415B
- Authority
- CN
- China
- Prior art keywords
- converter
- steam turbine
- motor
- driving device
- pump
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 131
- 238000000034 method Methods 0.000 title claims abstract description 23
- 238000010248 power generation Methods 0.000 claims abstract description 35
- 230000004907 flux Effects 0.000 claims description 52
- 230000005540 biological transmission Effects 0.000 claims description 6
- 239000003990 capacitor Substances 0.000 claims description 3
- 230000001276 controlling effect Effects 0.000 description 16
- 230000003068 static effect Effects 0.000 description 8
- 238000010586 diagram Methods 0.000 description 7
- 230000008569 process Effects 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000002457 bidirectional effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D13/00—Pumping installations or systems
- F04D13/02—Units comprising pumps and their driving means
- F04D13/06—Units comprising pumps and their driving means the pump being electrically driven
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D15/00—Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby
- F01D15/08—Adaptations for driving, or combinations with, pumps
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
- F01D21/00—Shutting-down of machines or engines, e.g. in emergency; Regulating, controlling, or safety means not otherwise provided for
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D13/00—Pumping installations or systems
- F04D13/02—Units comprising pumps and their driving means
- F04D13/04—Units comprising pumps and their driving means the pump being fluid driven
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D15/00—Control, e.g. regulation, of pumps, pumping installations or systems
- F04D15/0066—Control, e.g. regulation, of pumps, pumping installations or systems by changing the speed, e.g. of the driving engine
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J3/00—Circuit arrangements for ac mains or ac distribution networks
- H02J3/38—Arrangements for parallely feeding a single network by two or more generators, converters or transformers
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Control Of Turbines (AREA)
Abstract
The invention discloses a driving system and a driving control method of a steam turbine-motor driven feed pump, wherein the system comprises: a plurality of current transformers; the steam turbine-motor driving device is connected with the water feeding pump through a first converter and a second converter; the electric driving device is connected with the water feeding pump through a third converter and a second converter, and the electric driving device is connected with the steam turbine-motor driving device through the third converter and the first converter; the steam turbine-motor driving device is used for driving the water feeding pump and grid-connected power generation in a steam turbine driving water feeding pump and power generation operation mode, and the electric driving device is used for driving the water feeding pump in an electric driving water feeding pump starting mode. The invention can ensure that the steam turbine works at the highest efficiency point while realizing the control of the rotating speed of the feed pump, thereby improving the thermal efficiency of the system, and carrying out grid-connected power generation on surplus energy of the system so as to improve the utilization rate of comprehensive energy.
Description
Technical Field
The invention relates to the technical field of drive control of a feed pump, in particular to a drive system of a steam turbine-motor driven feed pump and a drive control method of the steam turbine-motor driven feed pump.
Background
In the current thermal power generation, a boiler feed pump is the most main energy consumption equipment for factories. The common water feeding pump driving mode is the variable speed driving of a small steam turbine or the driving of a motor, and particularly, for medium and large-sized units in a thermal power plant, a small steam turbine driving strategy is widely adopted.
However, the above driving strategy has the following problems, for example, because the load of the feed pump is changed correspondingly due to the change of the working condition of the power plant, the rotating speed of the power generation system is changed in a large range, and the overall efficiency of the system is affected.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the art described above. Therefore, an object of the present invention is to provide a driving system of a steam turbine-motor driven feed pump, which can ensure that a steam turbine operates at the highest efficiency point while controlling the rotation speed of the feed pump, so as to improve the thermal efficiency of the system, and can perform grid-connected power generation on surplus energy of the system, so as to improve the comprehensive energy utilization rate.
The second purpose of the invention is to provide a driving control method of the steam turbine-motor driven feed water pump.
In order to achieve the above object, a first embodiment of the present invention provides a driving system of a steam turbine-motor driven feed pump, comprising: a plurality of current transformers; the steam turbine-motor driving device is connected with the water feeding pump through a first converter and a second converter; the electric driving device is connected with the water feeding pump through a third converter and the second converter, and the electric driving device is connected with the steam turbine-motor driving device through the third converter and the first converter; the steam turbine-motor driving device is used for driving the water feeding pump and grid-connected power generation in a steam turbine driving water feeding pump and power generation operation mode, and the electric driving device is used for driving the water feeding pump in an electric driving water feeding pump starting mode.
According to the driving system of the steam turbine-motor driven feed pump of the embodiment of the invention, a plurality of converters, a steam turbine-motor driving device and an electric driving device are arranged, wherein the steam turbine-motor driving device is connected with the feed pump through a first converter and a second converter and can be used for driving the feed pump in the starting mode of the electric driving feed pump, the steam turbine-motor driving device is connected with the feed pump through a third converter and a second converter, the electric driving device is connected with the steam turbine-motor driving device through a third converter and the first converter and can be used for driving the feed pump in the steam turbine driving feed pump and generating operation mode and carrying out grid-connected power generation, therefore, the rotating speed control of the feed pump can be realized, the steam turbine can be ensured to work at the highest efficiency point, the thermal efficiency of the system can be improved, and the surplus energy of the system can be carried out grid-connected power generation, so as to improve the utilization rate of comprehensive energy.
In addition, the driving system of the steam turbine-motor driven feed water pump according to the above embodiment of the present invention may further have the following additional technical features:
according to one embodiment of the invention, when the steam turbine drives a water feeding pump and the power generation operation mode is that the steam turbine-motor driving device works normally under the starting working condition, the generated energy is transmitted to the second converter through the first converter to drive the water feeding pump to operate, and is transmitted to the third converter through the first converter to be connected to the grid for power generation; the electric drive water feed pump starting mode is that when the steam turbine-motor drive device does not work normally under the starting working condition, the electric drive device drives the second converter through the third converter to start the water feed pump.
According to one embodiment of the invention, the first converter employs rotor flux linkage directional control, the control outer loop employs rotational speed closed-loop control to maintain an optimal speed ratio for high cycle efficiency, and the control inner loop employs current closed-loop control to regulate the first motor flux linkage and electromagnetic torque; the second converter adopts rotor flux linkage directional control, a control outer ring of the second converter adopts rotating speed closed-loop control to determine the coaxial rotating speed of the water feeding pump and the second motor according to the water supply requirement of a boiler in a driving system of a steam turbine-motor driven water feeding pump, and a control inner ring of the second converter adopts current closed-loop control to adjust the flux linkage and the electromagnetic torque of the second motor; the third converter adopts directional control of the voltage of the power grid, the outer ring of the third converter adopts a direct current voltage loop to stabilize direct current voltage to adjust the transmission power and the flowing direction, and the inner ring of the third converter adopts an alternating current loop to adjust the grid-connected power factor as a unit power factor.
Further, the first converter and the second converter are both PWM rectifiers, and share a direct current bus and are connected in parallel; the third converter is a PWM inverter, and the third converter, the first converter and the second converter are connected back to back through capacitors.
Further, the steam turbine-motor driving device comprises a steam turbine and a first motor, wherein the rotor side of the first motor is coaxially connected with the steam turbine, and the stator side of the first motor is connected with the first converter.
Furthermore, the electric driving device comprises a filter, a transformer and a second motor, the filter is connected with a power grid through the transformer, the filtering device is connected with the second motor through the third converter and the second converter, and the second motor is connected with the water feeding pump.
According to one embodiment of the invention, the second motor is coaxially connected to the feed pump.
According to one embodiment of the invention, the first inverter is used for controlling the coaxial rotation speed of the steam turbine and the first motor, and the second inverter is used for controlling the coaxial rotation speed of the feed water pump and the second motor.
In order to achieve the above object, a second aspect of the present invention provides a method for controlling the driving of a steam turbine-motor driven feed pump, including the steps of: judging whether the steam turbine-motor driving device works normally under the starting working condition; if the steam turbine-motor driving device normally works under the starting working condition, the energy generated by the steam turbine-motor driving device is transmitted to the second converter through the first converter to drive the water feeding pump to operate, and meanwhile, the energy is transmitted to the third converter through the first converter to be connected to the grid for power generation; and if the steam turbine-motor driving device does not work normally under the starting working condition, the second converter is driven by the electric driving device through the third converter to start the water feeding pump.
According to the drive control method of the steam turbine-motor driven water feeding pump, whether the steam turbine-motor driving device normally works under the starting working condition is judged, if the steam turbine-motor driving device normally works under the starting working condition, the energy generated by the steam turbine-motor driving device is transmitted to the second converter through the first converter to drive the water feeding pump to operate, and meanwhile, the energy is transmitted to the third converter through the first converter to be connected to the grid for power generation; if the steam turbine-motor driving device does not work normally under the starting working condition, the electric driving device drives the second converter through the third converter to start the water feeding pump, so that the steam turbine can work at the highest efficiency point while the rotating speed of the water feeding pump is controlled, the heat efficiency of the system can be improved, surplus energy of the system can be subjected to grid-connected power generation, and the comprehensive energy utilization rate is improved.
In addition, the drive control method of the steam turbine-motor driven feed water pump according to the above embodiment of the present invention may further have the following additional technical features:
according to one embodiment of the invention, the first converter employs rotor flux linkage directional control, the control outer loop employs rotational speed closed-loop control to maintain an optimal speed ratio for high cycle efficiency, and the control inner loop employs current closed-loop control to regulate the first motor flux linkage and electromagnetic torque; the second converter adopts rotor flux linkage directional control, a control outer ring of the second converter adopts rotating speed closed-loop control to determine the coaxial rotating speed of the water feeding pump and the second motor according to the water supply requirement of a boiler in a driving system of the steam turbine-motor driven water feeding pump, and a control inner ring of the second converter adopts current closed-loop control to adjust the flux linkage and the electromagnetic torque of the second motor; the third converter adopts directional control of the voltage of the power grid, the outer ring of the third converter adopts a direct current voltage loop to stabilize direct current voltage to adjust the transmission power and the flowing direction, and the inner ring of the third converter adopts an alternating current loop to adjust the grid-connected power factor as a unit power factor.
Drawings
FIG. 1 is a schematic diagram of a drive system for a steam turbine-motor driven feedwater pump according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of an operational mode of a drive system for a steam turbine-motor driven feed pump in an electric driven feed pump startup mode in accordance with an embodiment of the present invention;
FIG. 3 is a schematic diagram of the operational mode of a steam turbine-motor driven feedwater pump drive system in a steam turbine driven feedwater pump and generating mode of operation in accordance with one embodiment of the present invention;
FIG. 4 is a schematic diagram of a first inverter control process in a steam turbine-motor driven feedwater pump drive system according to one embodiment of the present invention;
FIG. 5 is a schematic diagram of a second inverter control process in a steam turbine-motor driven feedwater pump drive system according to one embodiment of the present invention;
FIG. 6 is a schematic diagram of a third inverter control process in a steam turbine-motor driven feedwater pump drive system according to one embodiment of the present invention;
fig. 7 is a flowchart of a method for controlling the drive of a steam turbine-motor driven feed pump according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Fig. 1 is a schematic structural diagram of a drive system of a steam turbine-motor driven feed water pump according to an embodiment of the present invention.
As shown in fig. 1, the driving system of the steam turbine-motor driven feed water pump according to the embodiment of the present invention includes a plurality of inverters 10, a steam turbine-motor driving apparatus 20, and an electric driving apparatus 30, wherein the plurality of inverters 10 include a first inverter 101, a second inverter 102, and a third inverter 103, and the steam turbine-motor driving apparatus 20 is connected to a feed water pump 400 through the first inverter 101 and the second inverter 102; the electric drive 30 is connected to the feed pump 400 via a third converter 103 and a second converter 102, and the electric drive 30 is connected to the steam turbine-motor drive 20 via the third converter 103 and a first converter 101.
Among them, the turbine-motor driving device 20 is used to drive the feed water pump 400 and to perform grid-connected power generation in the turbine-driven feed water pump and power generation operation mode, and the motor driving device 30 is used to drive the feed water pump 400 in the motor-driven feed water pump start mode.
In an embodiment of the present invention, the first converter 101 and the second converter 102 may be both PWM rectifiers, and the third converter 103 may be a PWM inverter, wherein, as shown in fig. 1, the first converter 101 and the second converter 102 may be connected in parallel through a common dc bus, and the third converter 103 and the first converter 101 and the second converter 102 may be connected back to back through capacitors.
In one embodiment of the present invention, the first converter 101, the second converter 102 and the third converter 103 may be of a two-level voltage source type structure.
In another embodiment of the present invention, the first converter 101, the second converter 102 and the third converter 103 may be a three-level voltage source type structure.
In addition, the converter can also be in a modular multilevel structure and a cascaded H-bridge multilevel structure.
In one embodiment of the present invention, as shown in fig. 1, the steam turbine-motor driving apparatus 20 may include a steam turbine 201 and a first electric machine 202, wherein a rotor side of the first electric machine 202 may be coaxially connected to the steam turbine 201, and a stator side of the first electric machine 202 may be connected to the first converter 101. The rotor side of the first motor can be coaxially connected with the steam turbine to enable the steam turbine to carry out matching of rotating speed parameters, and the stator side of the first motor can be connected with the first converter to enable the first converter to carry out voltage and current grade matching.
In one embodiment of the present invention, as shown in fig. 1, the electric drive device 30 may include a filter 301, a transformer 302 and a second electric machine 303, wherein the filter may be connected to the grid 500 via the transformer 302 and may be connected to the second electric machine 303 via a third converter 103 and a second converter 102, the second electric machine 303 may be connected to a feed water pump, specifically, the rotor side of the second electric machine 303 may be coaxially connected to the feed water pump 400, and the stator side of the second electric machine 303 may be connected to the second converter 102. The rotor side of the second motor can be coaxially connected with the water feeding pump to enable the water feeding pump to carry out matching of rotating speed parameters, and the stator side of the second motor can be connected with the second converter to enable the water feeding pump to carry out voltage and current grade matching.
In another embodiment of the present invention, the electric drive device 30 may include a filter and a large reactance, wherein the filter may be embodied as an LCL filter and the large reactance may be embodied as a smoothing reactor.
In one embodiment of the present invention, the first motor 202 and the second motor 303 may be synchronous motors, wherein the second motor 303 may also be connected to the feed pump 400 through a gearbox 600, as shown in fig. 1. The second motor can adapt to the requirement of medium and low rotating speed by arranging the gear box.
In another embodiment of the present invention, the first electric machine 202 and the second electric machine 303 may be asynchronous machines.
It should be noted that the first converter 101 can control the coaxial rotation speeds of the steam turbine 201 and the first electric machine 202, the second converter 102 can control the coaxial rotation speeds of the feedwater pump 400 and the second electric machine 303, and the decoupling of the coaxial rotation speeds of the steam turbine 201 and the first electric machine 202 from the coaxial rotation speeds of the feedwater pump 400 and the second electric machine 303 can be realized through the first converter 101 and the second converter 102, wherein the first converter 101 specifically maintains the optimal speed ratio of the steam turbine 201 according to the relationship between the inter-stage annular efficiency and the rotation speed in the steam turbine 201, and the second converter 102 maintains the boiler feedwater demand in the driving system of the steam turbine-electric machine driven feedwater pump according to the relationship between the flow rate and the rotation speed of the feedwater pump 400. In addition, the first converter 101, the second converter 102 and the third converter 103 can have energy bidirectional flow capability and have a path for energy to be connected to the network.
Based on the structure, the driving system of the steam turbine-motor driven feed pump provided by the embodiment of the invention can realize the driving control of the feed pump under different driving modes, namely an electric driven feed pump starting mode and a steam turbine driven feed pump and power generation running mode.
The starting mode of the electric drive water feed pump is that the steam turbine-motor drive device 20 does not normally work under the starting working condition, namely, the steam turbine 201 has no steam admission when the driving system of the steam turbine-motor drive water feed pump is under the starting working condition; the steam turbine-driven feed pump and power generation operation mode is that the steam turbine-motor driving device 20 normally operates under the starting condition, that is, the steam turbine 201 enters steam to operate when the driving system of the steam turbine-motor driven feed pump is under the starting condition.
Further, as shown in fig. 2, if the drive system of the steam turbine-motor driven feed water pump is in the electric driven feed water pump start mode, the steam turbine-motor drive device 20 does not operate, the air intake valve 2011 of the steam turbine 201 is closed, and the first inverter 101 is locked, at which time the electric drive device 30 can drive the second inverter 102 through the third inverter 103 to start the feed water pump 400.
Further, as shown in fig. 3, if the drive system of the steam turbine-motor driven feed water pump is in the steam turbine driven feed water pump and power generation operation mode, the steam turbine-motor drive device 20 operates, the air intake valve 2011 of the steam turbine 201 is opened, and the rotation speed of the steam turbine 201 is set to the optimum rotation speed ratio, and at this time, the generated energy can be transmitted to the second converter 102 through the first converter 101 to drive the feed water pump 400 to operate, and can be transmitted to the third converter 103 through the first converter 101 to perform grid-connected power generation.
From the above, it can be seen that the driving system of the steam turbine-motor driven feed pump according to the embodiment of the present invention can drive the feed pump in different driving modes by controlling the first converter, the second converter, and the third converter.
Specifically, the driving system of the steam turbine-motor driven feed water pump according to the embodiment of the present invention can adjust the generated power and the operating power generated by the steam turbine 201 by controlling the first converter 101, the second converter 102, and the third converter 103, and adjust the rotation speed of the feed water pump 400, so as to realize the multi-directional flow of the generated power, so that the driving system of the steam turbine-motor driven feed water pump can drive the feed water pump in different driving modes.
More specifically, the driving system of the steam turbine-motor driven feed water pump according to the embodiment of the present invention can adjust the electromagnetic torque and the system input power of the first motor 201 by controlling the first converter 101 to keep the steam turbine 201 running at a constant speed, adjust the electromagnetic torque of the second motor 303 and the input power of the feed water pump 400 by controlling the second converter 102 to adjust the rotation speed of the feed water pump according to the boiler water supply requirement in the driving system of the steam turbine-motor driven feed water pump, and adjust the grid-connected power factor and the dc-side bus voltage by controlling the third converter 103 to connect the surplus power to the network to maintain the dc-bus voltage stable.
The first converter 101 may employ a rotor flux linkage directional control, the outer control loop may employ a rotational speed closed-loop control to maintain an optimal speed ratio for high cycle efficiency, and the inner control loop may employ a current closed-loop control to adjust the flux linkage and electromagnetic torque of the first electric machine 202. Further, as shown in fig. 4, for the first converter 101, the current rotation speed set value can be determined through the turbine optimal speed ratio curve, and then the rotation speed set value can be compared with the rotation speed of the first motor 202, and the comparison difference value is input into the rotation speed regulator without static difference, so that the output rotation speed can follow the given rotation speed value, meanwhile, according to the given rotation speed value, the flux linkage set value of the first motor 202 can be determined based on a constant flux or weak flux mode, and then the flux linkage set value can be compared with the motor flux linkage, and the comparison difference value is input into the flux linkage regulator without static difference, and finally, the output value according to the rotation speed regulator and the flux linkage regulator can be input into the first converter 101 as a control signal, so as to realize the rotation speed control of the turbine 201, and thus adjust and obtain the maximum wheel shaft power.
The second converter 102 can adopt rotor flux linkage directional control, the control outer ring of the second converter can adopt rotating speed closed-loop control to determine the coaxial rotating speed of the feed water pump and the second motor according to the water supply requirement of a boiler in a driving system of a steam turbine-motor driven feed water pump, and the control inner ring can adopt current closed-loop control to adjust the flux linkage and the electromagnetic torque of the second motor 303. Further, as shown in FIG. 5, the current speed set point is determined for the current feed water flow and operating condition curve of the feed water pump 400 of the second converter 102, further, the given value of the rotating speed can be compared with the current rotating speed of the second motor 303, and the comparison difference value is input into a rotating speed regulator without static difference, so that the output rotating speed can follow the given rotating speed value, meanwhile, the flux linkage set value of the second motor 303 can be determined based on a constant flux or weak flux mode according to the set rotating speed value, further, the flux set value can be compared with the flux of the second motor 303, the comparison difference value is input into a flux regulator without static difference, and finally the output value of the rotation speed regulating machine and the flux regulator can be used as a control signal to be input into the second converter 102 so as to realize the rotation speed control of the water feed pump 400, thereby meeting the water supply requirement of the boiler in the driving system of the steam turbine-motor driven water feeding pump.
The third converter 103 may adopt grid voltage directional control, the control outer loop may adopt a dc voltage loop to stabilize the dc voltage and adjust the transmission power and the flow direction, and the control inner loop may adopt an ac current loop to adjust the grid-connected power factor as the unit power factor. Further, as shown in fig. 6, for the third converter 103, the given value of the dc voltage and the actual value of the dc voltage may be compared, and the comparison difference may be input to the active regulator, and the third converter 103 is controlled by matching with the output of the reactive regulator, so as to implement the unit power factor regulation and the surplus energy absorption grid connection. Direct current voltage is adjusted through the current transformer, and the surplus power of the system can be connected to the grid for power generation, so that energy siltation of the system can be avoided, utilization of comprehensive energy is realized, and efficiency and operation economy of the system are improved.
According to the driving system of the steam turbine-motor driven feed pump provided by the embodiment of the invention, a plurality of converters, a steam turbine-motor driving device and an electric driving device are arranged, wherein the steam turbine-motor driving device is connected with the feed pump through a first converter and a second converter and can be used for driving the feed pump in a starting mode of the electric driving feed pump, the steam turbine-motor driving device is connected with the feed pump through a third converter and a second converter, the electric driving device is connected with the steam turbine-motor driving device through a third converter and the first converter and can be used for driving the feed pump in a steam turbine driving feed pump and generating operation mode and grid-connected power generation, therefore, the rotating speed control of the feed pump can be realized, the steam turbine can be ensured to work at the highest efficiency point, the thermal efficiency of the system can be improved, and surplus energy of the system can be subjected to grid-connected power generation, so as to improve the utilization rate of comprehensive energy.
In response to the drive system of the steam turbine-motor driven feed pump provided in the above embodiment, the embodiment of the present invention provides a drive control method of a steam turbine-motor driven feed pump.
As shown in fig. 7, the method for controlling the drive of the steam turbine-motor driven feed water pump according to the embodiment of the present invention includes the steps of:
and S1, judging whether the steam turbine-motor driving device works normally under the starting working condition.
And S2, if the steam turbine-motor driving device works normally under the starting working condition, transmitting the energy generated by the steam turbine-motor driving device to the second converter through the first converter to drive the water feeding pump to run, and simultaneously transmitting the energy to the third converter through the first converter to be connected to the grid for power generation.
And S3, if the steam turbine-motor driving device does not work normally under the starting working condition, the electric driving device drives the second converter through the third converter to start the feed water pump.
Specifically, whether the steam turbine-motor driving device works normally can be judged according to whether the steam turbine enters steam under the starting working condition, wherein if the steam turbine enters steam under the starting working condition, the normal work of the steam turbine-motor driving device can be judged, otherwise, the abnormal work of the steam turbine-motor driving device can be judged, and the water feeding pump is started in the starting mode of the electrically driven water feeding pump.
Further, as shown in fig. 2, if the driving system of the steam turbine-motor driven feed water pump is in the electric driven feed water pump start mode, the steam turbine-motor driving apparatus does not operate, the air intake valve 2011 of the steam turbine 201 is closed, and the first converter is locked, and at this time, the electric driving apparatus can drive the second converter through the third converter to start the feed water pump.
Further, as shown in fig. 3, if the driving system of the steam turbine-motor driven feed water pump is in the steam turbine driven feed water pump and power generation operation mode, the steam turbine-motor driving device operates, the air inlet valve of the steam turbine is opened, and the rotating speed of the steam turbine is set to the optimal rotating speed ratio, and at this time, the generated energy can be transmitted to the second converter through the first converter to drive the feed water pump to operate, and can be transmitted to the third converter through the first converter to be connected to the grid for power generation.
From the above, it can be seen that the drive control method for the steam turbine-motor driven feed water pump according to the embodiment of the present invention can realize the drive of the feed water pump in different drive modes by controlling the first converter, the second converter, and the third converter.
Specifically, according to the drive control method of the steam turbine-motor driven feed water pump provided by the embodiment of the invention, the generated power and the working power generated by the steam turbine can be adjusted by controlling the first converter, the second converter and the third converter, and the rotation speed of the feed water pump is adjusted at the same time, so that the multidirectional flow of the generated power is realized, and the drive control method of the steam turbine-motor driven feed water pump can drive the feed water pump in different drive modes.
More specifically, according to the drive control method of the steam turbine-motor driven feed water pump provided by the embodiment of the invention, the electromagnetic torque and the system input power of the first motor can be adjusted by controlling the first converter to keep the steam turbine running at a constant speed, the electromagnetic torque of the second motor and the input power of the feed water pump can be adjusted by controlling the second converter to adjust the rotation speed of the feed water pump according to the boiler water supply requirement in the drive control method of the steam turbine-motor driven feed water pump, and meanwhile, the grid-connected power factor and the direct-current side bus voltage can be adjusted by controlling the third converter to connect the surplus power to the network to maintain the direct-current bus voltage stable.
The first converter can adopt rotor flux linkage orientation control, the control outer ring can adopt rotating speed closed-loop control to maintain the optimal speed ratio of high cycle efficiency, and the control inner ring can adopt current closed-loop control to adjust the flux linkage and the electromagnetic torque of the first motor. Further, as shown in fig. 4, for the first converter, the current rotation speed set value can be determined through the optimal speed ratio curve of the steam turbine, and then the rotation speed set value can be compared with the rotation speed of the first motor, and the comparison difference value is input into the rotation speed regulator without static difference, so that the output rotation speed can follow the given rotation speed value, meanwhile, according to the given rotation speed value, the flux linkage set value of the first motor can be determined based on a constant flux or weak flux mode, and then the flux linkage set value can be compared with the flux linkage of the motor, and the comparison difference value is input into the flux linkage regulator without static difference, and finally, the output value according to the rotation speed regulator and the flux linkage regulator can be input into the first converter as a control signal, so as to realize the rotation speed control of the steam turbine, and further adjust and obtain the maximum shaft power.
The second converter can adopt rotor flux linkage directional control, the control outer ring of the second converter can adopt rotating speed closed-loop control to determine the coaxial rotating speed of the water feeding pump and the second motor according to the water supply requirement of a boiler in a driving control method of driving the water feeding pump by a steam turbine-motor, and the control inner ring of the second converter can adopt current closed-loop control to adjust the flux linkage and the electromagnetic torque of the second motor. Further, as shown in fig. 5, the current set value of the rotating speed is determined according to the current feed water flow and the working condition curve of the feed water pump available by the second converter, further, the given value of the rotating speed can be compared with the current rotating speed of the second motor, and the comparison difference value is input into a rotating speed regulator without static difference, so that the output rotating speed can follow the given rotating speed value, meanwhile, the flux linkage set value of the second motor can be determined based on a constant flux or weak flux mode according to the set rotating speed value, then the given value of the flux linkage can be compared with the flux linkage of the second motor, the comparison difference value is input into a flux linkage regulator without static difference, finally the output value of the rotation speed regulating machine and the flux linkage regulator can be used as control signals to be input into the second converter so as to realize the rotation speed control of the water feeding pump, thereby meeting the water supply requirement of the boiler in the driving control method of the steam turbine-motor driven water feeding pump.
The third converter can adopt power grid voltage directional control, the control outer ring can adopt a direct current voltage loop to stabilize direct current voltage and adjust the transmission power and the flow direction, and the control inner ring can adopt an alternating current loop to adjust grid-connected power factor as unit power factor. Further, as shown in fig. 6, for the third converter, the given value of the dc voltage and the actual value of the dc voltage may be compared, and the comparison difference may be input to the active regulator, and the third converter may be controlled by matching with the output of the reactive regulator, so as to implement unit power factor regulation and remaining energy consumption grid connection.
According to the drive control method of the steam turbine-motor driven water feeding pump provided by the embodiment of the invention, whether the steam turbine-motor driving device normally works under the starting working condition is judged, and if the steam turbine-motor driving device normally works under the starting working condition, the energy generated by the steam turbine-motor driving device is transmitted to the second converter through the first converter to drive the water feeding pump to operate, and is transmitted to the third converter through the first converter to be connected to the grid for power generation; if the steam turbine-motor driving device does not work normally under the starting working condition, the electric driving device drives the second converter through the third converter to start the water feeding pump, so that the steam turbine can work at the highest efficiency point while the rotating speed of the water feeding pump is controlled, the heat efficiency of the system can be improved, surplus energy of the system can be subjected to grid-connected power generation, and the comprehensive energy utilization rate is improved.
In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. The meaning of "plurality" is two or more unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "above," and "over" a second feature may be directly on or obliquely above the second feature, or simply mean that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., 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 are not necessarily intended to 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. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (2)
1. A drive system for a steam turbine-motor driven feed pump, comprising:
a plurality of current transformers;
the steam turbine-motor driving device is connected with the water feeding pump through a first converter and a second converter;
the electric driving device is connected with the water feeding pump through a third converter and the second converter, and the electric driving device is connected with the steam turbine-motor driving device through the third converter and the first converter;
the system comprises a steam turbine-motor driving device, a water supply pump, a power generation running mode, an electric driving device and a control device, wherein the steam turbine-motor driving device is used for driving the water supply pump and grid-connected power generation in the steam turbine driving water supply pump and power generation running mode, and the electric driving device is used for driving the water supply pump in the electric driving water supply pump starting mode;
the first converter adopts rotor flux linkage directional control, a control outer ring of the first converter adopts rotating speed closed-loop control to maintain the optimal speed ratio of high cycle efficiency, and a control inner ring of the first converter adopts current closed-loop control to adjust flux linkage and electromagnetic torque of a first motor in the steam turbine-motor driving device;
the second converter adopts rotor flux linkage directional control, a control outer ring adopts rotating speed closed-loop control to determine the coaxial rotating speed of the water feeding pump and a second motor in the electric driving device according to the water supply requirement of a boiler in a driving system of a steam turbine-motor driven water feeding pump, and a control inner ring adopts current closed-loop control to adjust the flux linkage and the electromagnetic torque of the second motor;
the third converter adopts the directional control of the voltage of the power grid, the control outer ring of the third converter adopts a direct current voltage loop to stabilize the direct current voltage and adjust the transmission power and the flowing direction, the control inner ring adopts an alternating current loop to adjust the grid-connected power factor as the unit power factor,
wherein,
when the steam turbine drives the water feeding pump and the power generation operation mode is that the steam turbine-motor driving device works normally under the starting working condition, the energy generated by the steam turbine-motor driving device is transmitted to the second converter through the first converter to drive the water feeding pump to operate, and is transmitted to the third converter through the first converter to be connected to the grid for power generation;
the electric drive water feed pump starting mode is that when the steam turbine-motor drive device does not work normally under the starting working condition, the electric drive device drives the second converter through the third converter to start the water feed pump,
wherein,
the first converter and the second converter are both PWM rectifiers, and share a direct current bus and are connected in parallel;
the third converter is a PWM inverter, the third converter and the first converter are connected with the second converter back to back through capacitors,
the steam turbine-motor driving device also comprises a steam turbine, the rotor side of the first motor is coaxially connected with the steam turbine, the stator side of the first motor is connected with the first converter,
the electric driving device also comprises a filter and a transformer, the filter is connected with a power grid through the transformer, the filter device is connected with the second motor through the third converter and the second converter, the second motor is connected with the water feeding pump,
wherein the second motor is coaxially connected with the water feeding pump,
the first converter is used for controlling the coaxial rotating speeds of the steam turbine and the first motor, and the second converter is used for controlling the coaxial rotating speeds of the feed water pump and the second motor.
2. A drive control method of a steam turbine-motor driven feed water pump including the drive system of the steam turbine-motor driven feed water pump according to claim 1, characterized by comprising the steps of:
judging whether the steam turbine-motor driving device works normally under the starting working condition;
if the steam turbine-motor driving device normally works under the starting working condition, transmitting the energy generated by the steam turbine-motor driving device to the second converter through the first converter to drive the water feeding pump to operate, and transmitting the energy to the third converter through the first converter to be connected to the grid for power generation;
if the steam turbine-motor driving device does not work normally under the starting working condition, the second converter is driven by the electric driving device through the third converter to start the water feeding pump;
the first converter adopts rotor flux linkage directional control, a control outer ring of the first converter adopts rotating speed closed-loop control to maintain the optimal speed ratio of high cycle efficiency, and a control inner ring of the first converter adopts current closed-loop control to adjust first motor flux linkage and electromagnetic torque in the steam turbine-motor driving device;
the second converter adopts rotor flux linkage directional control, a control outer ring of the second converter adopts rotating speed closed-loop control to determine the coaxial rotating speed of the water feeding pump and a second motor in the electric driving device according to the water supply requirement of a boiler in a driving system of the steam turbine-motor driven water feeding pump, and a control inner ring of the second converter adopts current closed-loop control to adjust the flux linkage and the electromagnetic torque of the second motor;
the third converter adopts directional control of the voltage of the power grid, the outer ring of the third converter adopts a direct current voltage loop to stabilize direct current voltage to adjust the transmission power and the flowing direction, and the inner ring of the third converter adopts an alternating current loop to adjust the grid-connected power factor as a unit power factor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010401448.XA CN111550415B (en) | 2020-05-13 | 2020-05-13 | Driving system and driving control method of steam turbine-motor driven water feeding pump |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010401448.XA CN111550415B (en) | 2020-05-13 | 2020-05-13 | Driving system and driving control method of steam turbine-motor driven water feeding pump |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111550415A CN111550415A (en) | 2020-08-18 |
| CN111550415B true CN111550415B (en) | 2022-05-03 |
Family
ID=72004679
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010401448.XA Active CN111550415B (en) | 2020-05-13 | 2020-05-13 | Driving system and driving control method of steam turbine-motor driven water feeding pump |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111550415B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113482729B (en) * | 2021-07-19 | 2022-10-11 | 内蒙古京泰发电有限责任公司 | Motor intelligent synchronous switching water supply system based on turbo generator set |
| CN113431639B (en) * | 2021-07-28 | 2023-09-29 | 华能秦煤瑞金发电有限责任公司 | Water supply pump speed regulating device and method |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5818595A (en) * | 1981-07-23 | 1983-02-03 | Hitachi Ltd | Driving of variable speed hydrauric rotary machine |
| CN205936721U (en) * | 2016-08-20 | 2017-02-08 | 济南永泉节能环保科技有限公司 | Joint drive arrangement of steam turbine and motor |
| CN108278131A (en) * | 2017-01-06 | 2018-07-13 | 山东电力工程咨询院有限公司 | A kind of power-balance power generation vapour electricity coaxial pair of drive feed-water pump and method |
| CN108397242B (en) * | 2017-02-08 | 2024-04-23 | 中国电力工程顾问集团华东电力设计院有限公司 | Control system and method for speed regulating small steam turbine based on asynchronous motor full-power converter |
| CN110500142A (en) * | 2019-08-01 | 2019-11-26 | 大唐郓城发电有限公司 | A kind of ultra supercritical double reheat power generation sets water supply mercury vapour electricity hybrid drive and method |
-
2020
- 2020-05-13 CN CN202010401448.XA patent/CN111550415B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN111550415A (en) | 2020-08-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1992496B (en) | Control structure of double-fed AC-DC-AC converter for wind power generation | |
| CN101136582B (en) | Control method of DC side-discharging circuit of full power convertor | |
| US6954004B2 (en) | Doubly fed induction machine | |
| US20030057703A1 (en) | Method of controlling electrical rotating machines connected to a common shaft | |
| CN111550415B (en) | Driving system and driving control method of steam turbine-motor driven water feeding pump | |
| WO2009082326A1 (en) | Method, system and device for controlling wind power plants | |
| CN101304234A (en) | Power converters | |
| CN101917013B (en) | Double-feed wind power generating system with energy storage function | |
| Holmes et al. | Cycloconvertor-excited divided-winding doubly-fed machine as a wind-power convertor | |
| CN107147103A (en) | Electrical Propulsion Ship direct current networking power system | |
| CN108054967B (en) | Brushless double-fed motor-based diesel power generation system and control method thereof | |
| CN105977984A (en) | Variable-frequency main power source ship power station | |
| CN102522777A (en) | Wind driven generator set | |
| CN107332484A (en) | A kind of converters | |
| CN206874493U (en) | A kind of auxiliary power system for two-shipper backheat | |
| Wegiel et al. | Variable speed small hydropower plant | |
| Spee et al. | Adaptive control strategies for variable-speed doubly-fed wind power generation systems | |
| CN202261153U (en) | Control device of variable speed constant frequency generator for hydroelectric power generation | |
| CN106655625A (en) | Generalized frequency conversion system with forepump | |
| CN201191814Y (en) | AC electric motor speed regulating control device | |
| CN205882706U (en) | Frequency conversion main power source ship power station | |
| CN105162168A (en) | Wind generator system grid connection control method | |
| CN212616118U (en) | Transmission device capable of running at variable speed or constant speed and having external oil supply function and transmission system | |
| CN204886644U (en) | Power generation system is taken to magnetic coupling axle | |
| CN105119464A (en) | Magnetic coupling shaft generation system and application of magnetic coupling shaft generation system in ship |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |