阅读说明：本技术 永磁耦合器异轴布置的汽电气三源动力总成及其工作方法 (Steam-electricity three-source power assembly with permanent magnet coupler arranged in different shafts and working method thereof ) 是由 王林 杨博 赵景涛 高景辉 宋晓辉 张亚夫 王红雨 孟颖琪 于 2020-07-22 设计创作，主要内容包括：本发明公开了一种永磁耦合器异轴布置的汽电气三源动力总成及其工作方法,汽轮机的输出轴通过第一调速型永磁耦合器与减速机的第一输入轴相连接,电动机的输出轴通过第二调速型永磁耦合器与减速机的第二输入轴相连接,气动马达的输出轴通过第三调速型永磁耦合器与减速机的第三输入轴相连接,减速机的输出轴与外界的转动机械相连接；控制系统与汽轮机、第一调速型永磁耦合器、电动机、第二调速型永磁耦合器、气动马达及第三调速型永磁耦合器相连接,该动力总成及其工作方法具有节省电能、启动及停机操作简单、耗时较短的特点。(The invention discloses a steam-electricity three-source power assembly with a permanent magnet coupler arranged in a different shaft manner and a working method thereof.A steam turbine output shaft is connected with a first input shaft of a speed reducer through a first speed regulation type permanent magnet coupler, an electric motor output shaft is connected with a second input shaft of the speed reducer through a second speed regulation type permanent magnet coupler, an air motor output shaft is connected with a third input shaft of the speed reducer through a third speed regulation type permanent magnet coupler, and the output shaft of the speed reducer is connected with an external rotating machine; the control system is connected with the steam turbine, the first speed-regulating permanent magnet coupler, the motor, the second speed-regulating permanent magnet coupler, the pneumatic motor and the third speed-regulating permanent magnet coupler.)

1. A steam-electric three-source power assembly with permanent magnet couplers arranged in different shafts is characterized by comprising a control system, a steam turbine (1), a first speed-regulating permanent magnet coupler (2), a motor (3), a second speed-regulating permanent magnet coupler (4), a pneumatic motor (7) and a third speed-regulating permanent magnet coupler (6);

an output shaft of the steam turbine (1) is connected with a first input shaft of the speed reducer (5) through a first speed regulation type permanent magnet coupler (2), an output shaft of the motor (3) is connected with a second input shaft of the speed reducer (5) through a second speed regulation type permanent magnet coupler (4), an output shaft of the pneumatic motor (7) is connected with a third input shaft of the speed reducer (5) through a third speed regulation type permanent magnet coupler (6), and an output shaft of the speed reducer (5) is mechanically connected with external rotating machinery;

the control system is connected with the steam turbine (1), the first speed-regulating permanent magnet coupler (2), the motor (3), the second speed-regulating permanent magnet coupler (4), the pneumatic motor (7) and the third speed-regulating permanent magnet coupler (6).

2. The steam-electric three-source power assembly with the permanent magnet coupler coaxially arranged according to claim 1, wherein the speed reducer (5) is a spiral bevel speed reducer or a helical tooth speed reducer.

3. A working method of a steam-electric three-source power assembly with a permanent magnet coupler arranged in a different shaft mode is characterized by comprising the following steps:

at the initial stage of starting, the load carried by the rotating machinery is light, the output of the rotating machinery is required to be not more than 30% of the rated output, and the motor (3) is used as a power source at the stage;

in the normal operation stage, the output of the rotating machine is required to be within the range of 30% -100% of rated output and can be continuously adjusted, and a steam turbine (1) is used as a power source in the stage;

in the shutdown stage, the load of the rotating machinery is 0, only low-speed rotation of the equipment is required at the moment, the normal turning of the steam turbine (1) is ensured, and the pneumatic motor (7) is used as a power source in the stage.

4. The working method of the steam-electric three-source power assembly with the permanent magnet coupler arranged in the different shafts is characterized by comprising the following steps:

air gaps between conductor discs and magnet discs in a first speed-regulating permanent magnet coupler (2), a second speed-regulating permanent magnet coupler (4) and a third speed-regulating permanent magnet coupler (6) are positioned at the maximum position, and torque transmission among a steam turbine (1), an electric motor (3), a pneumatic motor (7) and a speed reducer (5) is 0;

starting the motor (3), gradually reducing an air gap between a conductor disc and a magnet disc in the second speed-regulating permanent magnet coupler (4), gradually increasing the torque transmitted between the motor (3) and the speed reducer (5) to a rated value from zero, continuously adjusting the output of the rotating machinery within the range of 0-30% of the rated output at the moment, and meeting the requirement of the initial starting stage, wherein the steam turbine (1) performs pipe warming and impulse rotation at the same time, and after the steam turbine (1) runs stably, the power source is required to be switched to the steam turbine (1), and the steam turbine (1) is used as the power source;

in the normal operation stage, when the steam turbine (1) is in fault tripping, the motor (3) is started, and the air gap between the conductor disc and the magnet disc in the second speed-regulating permanent magnet coupler (4) is directly regulated to the minimum value so as to transmit the maximum torque;

in the shutdown stage, when the motor (3) works at the moment, the air gap between the conductor disc and the magnet disc in the second speed regulation type permanent magnet coupler (4) is increased so as to disconnect the elastic connection between the motor (3) and the speed reducer (5); when the steam turbine (1) works at the moment, the steam turbine (1) is gradually stopped, meanwhile, the pneumatic motor (7) starts to be gradually started, and in the period, the air gaps between the conductor discs and the magnet discs in the first speed regulation type permanent magnet coupler (2) and the third speed regulation type permanent magnet coupler (6) are adjusted according to the rotating speed required by turning, so that the steam turbine (1) can be guaranteed to be capable of maintaining the normal turning rotating speed.

Technical Field

The invention relates to a steam-electric three-source power assembly and a working method thereof, in particular to a steam-electric three-source power assembly with a permanent magnet coupler arranged in a different shaft mode and a working method thereof.

Background

The power production process of coal-fired power plants determines that a large number of fans, water pumps and various rotating machines need to be arranged in the power plants. Typically, these fans or pumps are driven by electric motors. The motor driving mode has the advantages of being fast in starting and stopping, stable and reliable, but with stricter energy consumption index assessment of the thermal power generating units, reduction of plant power consumption rate becomes a problem which has to be considered by many thermal power plants.

The small steam turbine is used for replacing a motor to drive equipment with larger electric power, such as a draught fan, a feed pump and the like, so that the power consumption of the equipment in a plant can be obviously reduced, and the small steam turbine is widely applied to a power plant at present. The steam-driven equipment utilizes the steam produced by the boiler of the unit as an energy source, can effectively improve the energy consumption level of the unit, but also has the following defects:

1. the starting process is complicated, the consumed time is long, and the load speed of the unit and the net belt is influenced. In the starting process of the small steam turbine, 4-5 hours are often needed until a fan, a water pump and the like reach normal operation rotating speed through turning, pipe warming, rushing, warming and speed fixing. Compared with the switching-on of an electric equipment switch, the equipment can be started within several minutes, the time and the labor are obviously wasted, and the starting grid-connected speed of the unit is tired.

2. The shutdown process is complicated and takes a long time. A steam turbine turning motor needs to be additionally equipped. After the steam-driven equipment is normally stopped or is stopped in an accident, in order to ensure that the main shaft of the steam turbine is not damaged, the shaft seal needs to be maintained and a turning gear is put into the shaft seal, the main shaft is kept at a rotating speed, the machine can be completely stopped after 2-3 hours, and the whole stopping process takes a long time.

The permanent magnet coupler is also called a magnetic coupling and a permanent magnet transmission device. The magnetic rotor mainly comprises a conductor rotor, a magnetic rotor and a controller. Generally, the conductor rotor is connected to the motor shaft, the permanent magnet rotor is connected to the shaft of the working machine, there is an air gap (called air gap) between the conductor rotor and the permanent magnet rotor, and there is no mechanical connection for transmitting torque. Therefore, a soft (magnetic) connection is formed between the motor and the working machine, and the torque and the rotating speed of the working machine shaft are changed by adjusting the air gap. Because of the difference of air gap adjusting modes, the permanent magnet eddy current transmission device is divided into different types such as a standard type, a delay type, a speed regulation type and the like.

The permanent magnet coupler integrates non-contact and super-elastic (soft) transmission, can greatly reduce impact and vibration, and reduces the starting current of equipment. Meanwhile, the transmission efficiency is high, and the service life is long.

How to effectively combine the power saving advantage of the pneumatic equipment and the quick characteristic of the electric equipment and give full play to the advantages of the two is a problem worthy of research.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a steam-electric three-source power assembly with a permanent magnet coupler arranged in a different shaft mode and a working method thereof.

In order to achieve the purpose, the steam-electric three-source power assembly with the permanent magnet couplers arranged in different shafts comprises a control system, a steam turbine, a first speed-regulating permanent magnet coupler, a motor, a second speed-regulating permanent magnet coupler, a pneumatic motor and a third speed-regulating permanent magnet coupler;

an output shaft of the steam turbine is connected with a first input shaft of the speed reducer through a first speed-regulating permanent magnet coupler, an output shaft of the motor is connected with a second input shaft of the speed reducer through a second speed-regulating permanent magnet coupler, an output shaft of the pneumatic motor is connected with a third input shaft of the speed reducer through a third speed-regulating permanent magnet coupler, and an output shaft of the speed reducer is connected with external rotating machinery;

the control system is connected with the steam turbine, the first speed-regulating permanent magnet coupler, the motor, the second speed-regulating permanent magnet coupler, the pneumatic motor and the third speed-regulating permanent magnet coupler.

The speed reducer is a spiral umbrella speed reducer or a helical gear speed reducer.

The working method of the steam-electric three-source power assembly with the permanent magnet coupler arranged in different shafts comprises the following steps:

in the initial starting stage, the load of the rotating machinery is light, the output of the rotating machinery is required to be not more than 30% of the rated output, and the motor is used as a power source in the stage;

in the normal operation stage, the output of the rotating machine is required to be within the range of 30% -100% of rated output and can be continuously adjusted, and a steam turbine is used as a power source in the stage;

and in the shutdown stage, the load of the rotating machinery is 0, the equipment is only required to rotate at a low speed at the moment, the normal turning of the steam turbine is ensured, and the pneumatic motor is used as a power source in the stage.

The method specifically comprises the following steps:

setting air gaps between conductor discs and magnet discs in a first speed-regulating permanent magnet coupler, a second speed-regulating permanent magnet coupler and a third speed-regulating permanent magnet coupler at the maximum position, and enabling torque transmission among a steam turbine, an electric motor, a pneumatic motor and a speed reducer to be 0;

starting the motor, gradually reducing an air gap between a conductor disc and a magnet disc in the second speed-regulating permanent magnet coupler to enable torque transmitted between the motor and the speed reducer to gradually increase from zero to a rated value, continuously adjusting the output of the rotating machinery within a range of 0-30% of the rated output at the moment to meet the requirement of the initial starting stage, simultaneously warming and turning the steam turbine, requesting to switch a power source to the steam turbine after the steam turbine runs stably, and taking the steam turbine as the power source;

in the normal operation stage, when the steam turbine is in fault tripping, the motor is started, and the air gap between the conductor disc and the magnet disc in the second speed-regulating permanent magnet coupler is directly regulated to the minimum value so as to transmit the maximum torque;

in the shutdown stage, when the motor works at the moment, the air gap between the conductor disc and the magnet disc in the second speed regulation type permanent magnet coupler is increased so as to disconnect the elastic connection between the motor and the speed reducer; when the steam turbine works at the moment, the steam turbine is gradually stopped, meanwhile, the pneumatic motor starts to be gradually started, and in the period, the air gaps between the conductor discs and the magnet discs in the first speed-regulating permanent magnet coupler and the third speed-regulating permanent magnet coupler are adjusted according to the rotating speed required by the turning, so that the steam turbine can maintain the normal turning rotating speed.

The invention has the following beneficial effects:

the steam-electric three-source power assembly with the permanent magnet couplers arranged in a different-shaft mode and the working method thereof utilize the steam turbine, the electric motor and the pneumatic motor as power sources in different stages during specific operation, namely, the electric motor is used as the power source in the initial starting stage, the steam turbine is used as the power source in the normal operation stage, and the pneumatic motor is used as the power source in the shutdown stage, so that the advantages of quick starting and stopping of the electric motor drive and low plant rate of the steam turbine drive can be exerted, the steam-electric three-source power assembly has remarkable excellent comprehensive efficiency, saves electric energy, and simultaneously realizes thorough intervention and quitting of the steam turbine, the electric motor and the pneumatic motor by utilizing the three speed-regulating permanent magnet couplers.

Furthermore, when the steam turbine is in fault tripping, the motor is started, the function of steam-driven switching and electric driving under the accident condition is achieved, and the availability and the reliability of the equipment are greatly improved.

Furthermore, the pneumatic motor is used as a turbine stopping and turning device, and compared with an independent small motor, the energy-saving and cost-saving device has obvious energy-saving and cost advantages.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Wherein, 1 is a steam turbine, 2 is a first speed-regulating permanent magnet coupler, 3 is a motor, 4 is a second speed-regulating permanent magnet coupler, 5 is a speed reducer, 6 is a third speed-regulating permanent magnet coupler, and 7 is a pneumatic motor.

Detailed Description

The invention is described in further detail below with reference to the accompanying drawings:

referring to fig. 1, the steam-electric three-source power assembly with the different-axis arrangement of the permanent magnet couplers comprises a control system, a steam turbine 1, a first speed-regulating permanent magnet coupler 2, a motor 3, a second speed-regulating permanent magnet coupler 4, a pneumatic motor 7 and a third speed-regulating permanent magnet coupler 6; an output shaft of the steam turbine 1 is connected with a first input shaft of a speed reducer 5 through a first speed regulation type permanent magnet coupler 2, an output shaft of a motor 3 is connected with a second input shaft of the speed reducer 5 through a second speed regulation type permanent magnet coupler 4, an output shaft of a pneumatic motor 7 is connected with a third input shaft of the speed reducer 5 through a third speed regulation type permanent magnet coupler 6, and an output shaft of the speed reducer 5 is mechanically connected with external rotating machinery; the control system is connected with the steam turbine 1, the first speed-regulating permanent magnet coupler 2, the motor 3, the second speed-regulating permanent magnet coupler 4, the pneumatic motor 7 and the third speed-regulating permanent magnet coupler 6, and preferably, the speed reducer 5 is a spiral bevel speed reducer or a helical tooth speed reducer.

The working method of the steam-electric three-source power assembly with the permanent magnet coupler arranged in different shafts comprises the following steps:

the steam turbine 1 utilizes the self-produced steam of the boiler as the energy source, drives the impeller rotatory to produce power, rethread first speed governing type permanent magnet coupler 2 and speed reducer 5 finally drive and rotate mechanical work, and the theory of operation of first speed governing type permanent magnet coupler 2 is: the torque transmitted to the speed reducer 5 by the steam turbine 1 is adjusted by adjusting the size of the air gap between the conductor disc and the magnet disc, wherein the torque continuously changes from 0 to a rated value range, and the stable intervention and stable exit of a power source are realized.

The motor 3 is connected with the speed reducer 5 through the second speed regulation type permanent magnet coupler 4, and the second speed regulation type permanent magnet coupler 4 mainly functions to reduce large torque impact at the moment of starting, reduce starting current of equipment and realize stable intervention and exit of a power source.

The pneumatic motor 7 uses compressed air as a power source, then uses high-pressure compressed air to push the inner impeller to rotate, then transmits power to the speed reducer 5 through the output shaft and the third speed-regulating permanent magnet coupler 6, finally drives the rotating machinery to rotate at a low speed, and simultaneously drives the low-speed turning gear of the steam turbine 1.

The specific working process of the invention is as follows:

during working, the system is divided into a starting initial stage, a normal operation stage and a shutdown stage;

in the initial stage of starting, the load carried by the rotating machine is light, the output of the rotating machine is required to be not more than 30% of the rated output, and the low-power motor 3 is used as a power source in the stage.

In the normal operation stage, the output of the rotating machine is required to be within the range of 30-100% of rated output and can be continuously adjusted, and the steam turbine 1 is used as a power source in the stage.

And in the shutdown stage, the load of the rotating machinery is 0, the equipment is only required to rotate at a low speed at the moment, the normal turning of the steam turbine 1 is ensured, and the pneumatic motor 7 is used as a power source in the stage.

The specific application process is as follows:

1) air gaps between conductor discs and magnet discs in the first speed-regulating permanent magnet coupler 2, the second speed-regulating permanent magnet coupler 4 and the third speed-regulating permanent magnet coupler 6 are positioned at the maximum position, and the torque transmission among the steam turbine 1, the electric motor 3, the pneumatic motor 7 and the speed reducer 5 is 0;

2) starting the motor 3, gradually reducing the air gap between the conductor disc and the magnet disc in the second speed-regulating permanent magnet coupler 4, so that the torque transmitted between the motor 3 and the speed reducer 5 is gradually increased from zero to a rated value, the output of the rotating machine is continuously adjusted within the range of 0-30% of the rated output at the moment, the requirement of the initial starting stage is met, meanwhile, the steam turbine 1 performs pipe warming and impulse rotation, after the steam turbine 1 operates stably, the power source switching is requested, and the switching process is as follows: firstly, the rotating speed of the steam turbine 1 is increased to be 10r/min-20r/min higher than the rotating speed of the motor 3, then the air gap between the conductor disc and the magnet disc in the first speed-regulating permanent magnet coupler 2 is gradually reduced, the power of the steam turbine 1 starts to intervene, when the rotating speed of the rotating machine starts to increase, the motor 3 is stopped, the air gap between the conductor disc and the magnet disc in the second speed-regulating permanent magnet coupler 4 is increased, the motor 3 completely exits, and at the moment, the power source of the rotating machine is switched to the steam turbine 1 without interference by the motor 3.

In the normal operation stage, when the steam turbine 1 is in fault trip, the motor 3 is started, and the air gap between the conductor disc and the magnet disc in the second speed-regulating permanent magnet coupler 4 is directly regulated to the minimum value so as to transmit the maximum torque;

when the equipment needs to be shut down, when the motor 3 works at the moment, the air gap between the conductor disc and the magnet disc in the second speed regulation type permanent magnet coupler 4 is increased to disconnect the elastic connection between the motor 3 and the speed reducer 5, when the steam turbine 1 works at the moment, as the turning after the shutdown is involved, the pneumatic motor 7 is started when the steam turbine 1 starts to be shut down gradually, and during the period, the air gaps between the conductor disc and the magnet disc in the first speed regulation type permanent magnet coupler 2 and the third speed regulation type permanent magnet coupler 6 are adjusted according to the rotating speed required by the turning, so that the normal turning rotating speed of the steam turbine 1 can be maintained.