阅读说明：本技术 分散式风电机组液压变桨距装置及变桨控制方法 (Hydraulic variable pitch device of distributed wind turbine generator and pitch control method ) 是由 常亚民 易伟峰 姚晓丽 朱壮华 赵昕 王文彦 梁俊平 冉建军 王立新 殷志刚 赵 于 2021-10-30 设计创作，主要内容包括：一种分散式风电机组液压变桨距装置及变桨控制方法。现有技术采用的电动变桨距其传输扭矩矩小,低温下蓄电池存能量降低较快,结构复杂,液压变桨距,桨叶和塔架等部件的载荷不均匀,桨距角使输出功率不平稳,可靠性较差。本发明其组成包括：变桨距控制器(5),所述的变桨距控制器与变桨机构(6)连接,所述的变桨机构与风轮(1)的桨叶连接,所述的风轮通过连接轴与齿轮增速装置(2)连接,所述的齿轮增速装置通过连接轴与发电机(3)连接,所述的发电机分别连接电网、功率传感器(4),所述的功率传感器与所述的变桨距控制器连接,所述的变桨距控制器具有速度控制器(7)、功率控制器(8)。本发明用于分散式风电机组液压变桨距装置。(A hydraulic variable pitch device and a variable pitch control method for a distributed wind turbine generator are disclosed. The electric variable pitch adopted by the prior art has the advantages of small transmission torque moment, quick reduction of the stored energy of a storage battery at low temperature, complex structure, uneven load of components such as a hydraulic variable pitch, a blade, a tower and the like, unstable output power caused by the pitch angle and poor reliability. The invention comprises the following components: the variable pitch control device comprises a variable pitch controller (5), the variable pitch control device is connected with a variable pitch mechanism (6), the variable pitch mechanism is connected with blades of a wind wheel (1), the wind wheel is connected with a gear speed increasing device (2) through a connecting shaft, the gear speed increasing device is connected with a generator (3) through the connecting shaft, the generator is respectively connected with a power grid and a power sensor (4), the power sensor is connected with the variable pitch control device, and the variable pitch control device is provided with a speed controller (7) and a power controller (8). The hydraulic variable pitch device is used for the distributed wind turbine generator hydraulic variable pitch device.)

1. The utility model provides a distributed wind turbine generator system hydraulic pressure variable pitch device which constitutes and includes: the pitch controller is characterized in that: the variable pitch controller is connected with a variable pitch mechanism, the variable pitch mechanism is connected with blades of a wind wheel, the wind wheel is connected with a gear speed increasing device through a connecting shaft, the gear speed increasing device is connected with a generator through the connecting shaft, the generator is respectively connected with a power grid and a power sensor, the power sensor is connected with the variable pitch controller, the variable pitch controller is provided with a speed controller and a power controller, the speed controller controls a given rotating speed, and the power controller controls given power.

2. The distributed wind turbine hydraulic pitch control device and the pitch control method according to claim 1, wherein: the method comprises the following steps:

firstly, before an engine is merged into a power grid, a speed controller carries out variable pitch control according to a rotating speed feedback signal of the engine, the blade of a wind wheel is determined to be in a standby or feathering position according to a rotating speed and a wind speed signal, a power controller acts after the engine is merged into the power grid, a power regulator is usually controlled by pi or pid, and a power error signal is subjected to pi operation to obtain a pitch angle position;

a power signal of the generator is input to the plc in an analog quantity form by a high-speed power transmitter, namely 0-10 v corresponds to 0-800 kw of power, a pitch angle feedback signal, namely 0-10 v corresponds to 0-90 degrees of pitch angle, is input to an analog input unit of the plc in an analog quantity form, and a hydraulic sensor is input in an analog quantity form;

when the wind speed is increased, the variable pitch hydraulic cylinder pushes the blades to rotate towards the increasing direction of the pitch angle, so that the wind energy absorbed by the blades is reduced, the wind wheel is maintained to operate within the range of rated rotating speed, when the wind speed is reduced, reverse operation is carried out, the power absorbed by the wind wheel is basically kept constant, and the blades are adjusted to the preset pitch more quickly and accurately;

when the wind turbine is in a shutdown state, the pitch angle is at a 90-degree position, the airflow does not generate torque to the blades, the pitch angle is reduced to 15 degrees from 90 degrees at a certain speed, if the wind speed reaches the grid-connected wind speed, the pitch angle is continuously reduced to a 3-degree generator and is connected with a power grid, and when the wind speed is less than the rated wind speed, the pitch angle is kept unchanged at 3 degrees;

when the wind speed is higher than the rated wind speed, the controller outputs-10V- +10V voltage to the proportional valve according to the power feedback signal, the direction and the size of the output flow of the proportional valve are controlled, the pitch angle of the blade is controlled by the pitch-variable hydraulic cylinder according to the flow and the direction output by the proportional valve, the output power is maintained near the rated power, and if a fault occurs or a shutdown command exists, the controller outputs a rapid feathering command, so that the wind turbine can be rapidly shut down.

Technical Field

The invention relates to the technical field of wind power generation, in particular to a hydraulic variable pitch device of a distributed wind turbine generator and a variable pitch control method.

Background

The electric load center of the distributed wind power generation is not used for large-scale long-distance power transmission, the generated power is connected to a power grid nearby, the electric variable pitch adopted by the existing variable pitch actuating mechanism is complex in structure and not suitable for application of large-scale wind power generators, the transmission torque moment of the electric variable pitch is transmitted, the stored energy of a storage battery is reduced quickly at low temperature, the service life of the battery is short, the existing hydraulic variable pitch is not consistent with the application of the large-scale wind power generators, the loads of components such as blades and towers are not uniform, the output power is unstable due to the pitch angle, and the reliability is poor.

Disclosure of Invention

The invention aims to provide a hydraulic variable pitch device and a variable pitch control method for a distributed wind turbine generator, which adopt a hydraulic variable pitch control variable pitch structure to solve the problem of uneven load of components such as blades, towers and the like, and have the advantages of compact and simple structure, easy application of various controls, high reliability and the like.

The above purpose is realized by the following technical scheme:

the utility model provides a distributed wind turbine generator system hydraulic pressure variable pitch device which constitutes and includes: the variable pitch control device is connected with the variable pitch mechanism, the variable pitch mechanism is connected with blades of a wind wheel, the wind wheel is connected with a gear speed increasing device through a connecting shaft, the gear speed increasing device is connected with a generator through a connecting shaft, the generator is respectively connected with a power grid and a power sensor, the power sensor is connected with the variable pitch control device, the variable pitch control device is provided with a speed controller and a power controller, the speed controller controls the given rotating speed, and the power controller controls the given power.

A hydraulic variable pitch device and a variable pitch control method for a distributed wind turbine generator set comprise the following steps: firstly, before an engine is merged into a power grid, a speed controller carries out variable pitch control according to a rotating speed feedback signal of the engine, the blade of a wind wheel is determined to be in a standby or feathering position according to a rotating speed and a wind speed signal, a power controller acts after the engine is merged into the power grid, a power regulator is usually controlled by pi or pid, and a power error signal is subjected to pi operation to obtain a pitch angle position;

a power signal of the generator is input to the plc in an analog quantity form by a high-speed power transmitter, namely 0-10 v corresponds to 0-800 kw of power, a pitch angle feedback signal, namely 0-10 v corresponds to 0-90 degrees of pitch angle, is input to an analog input unit of the plc in an analog quantity form, and a hydraulic sensor is input in an analog quantity form;

when the wind speed is increased, the variable pitch hydraulic cylinder pushes the blades to rotate towards the increasing direction of the pitch angle, so that the wind energy absorbed by the blades is reduced, the wind wheel is maintained to operate within the range of rated rotating speed, when the wind speed is reduced, reverse operation is carried out, the power absorbed by the wind wheel is basically kept constant, and the blades are adjusted to the preset pitch more quickly and accurately;

when the wind turbine is in a shutdown state, the pitch angle is at a 90-degree position, the airflow does not generate torque to the blades, the pitch angle is reduced to 15 degrees from 90 degrees at a certain speed, if the wind speed reaches the grid-connected wind speed, the pitch angle is continuously reduced to a 3-degree generator and is connected with a power grid, and when the wind speed is less than the rated wind speed, the pitch angle is kept unchanged at 3 degrees;

when the wind speed is higher than the rated wind speed, the controller outputs-10V- +10V voltage to the proportional valve according to the power feedback signal, the direction and the size of the output flow of the proportional valve are controlled, the pitch angle of the blade is controlled by the pitch-variable hydraulic cylinder according to the flow and the direction output by the proportional valve, the output power is maintained near the rated power, and if a fault occurs or a shutdown command exists, the controller outputs a rapid feathering command, so that the wind turbine can be rapidly shut down.

Has the advantages that:

1. the invention relates to a hydraulic variable pitch device of a distributed wind turbine generator and a pitch control method thereof, wherein the hydraulic variable pitch control pitch structure solves the problem of uneven load of components such as blades, a tower and the like, has the advantages of compact and simple structure, high reliability and the like, can ensure the safe and reliable operation of the wind turbine generator, prolongs the service life of a wind turbine, ensures the output power to be stable, reduces the torque oscillation and the cabin oscillation by controlling the pitch angle, not only optimizes the output power, but also effectively reduces the noise, stabilizes the output power of the generator, improves the stress condition of the blades and the whole machine, and is suitable for the control of the variable pitch of a large wind turbine generator.

2. The speed regulating device reduces the trend that the rotating speed of the impeller is accelerated due to the increase of the wind speed by increasing the pitch angle, when the wind speed is increased, the pitch-variable hydraulic cylinder acts to push the blades to rotate towards the direction of increasing the pitch angle so as to reduce the wind energy absorbed by the blades, the wind wheel is maintained to operate within the range of rated rotating speed, and when the wind speed is reduced, the opposite operation is carried out, so that the power absorbed by the wind wheel can be basically kept constant.

3. The hydraulic control system has the advantages of large transmission torque, light weight, high rigidity, accurate positioning, high dynamic response speed of the hydraulic actuating mechanism and the like, and can ensure that the blades are adjusted to the preset pitch more quickly and accurately.

Description of the drawings:

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

FIG. 2 is a control block diagram of a variable pitch wind turbine according to the present invention.

FIG. 3 is a diagram of a hydraulic pitch control system of the present invention.

Wherein: 1. the wind wheel, 2, the gear speed increasing device, 3, the generator, 4, the power sensor, 5, the variable pitch controller, 6, the variable pitch mechanism, 7, the speed controller, 8 and the power controller.

The specific implementation mode is as follows:

example 1:

the utility model provides a distributed wind turbine generator system hydraulic pressure variable pitch device which constitutes and includes: the variable-pitch control device comprises a variable-pitch controller 5, the variable-pitch controller is connected with a variable-pitch mechanism 6, the variable-pitch mechanism is connected with blades of a wind wheel 1, the wind wheel is connected with a gear speed increasing device 2 through a connecting shaft, the gear speed increasing device is connected with a generator 3 through the connecting shaft, the generator is respectively connected with a power grid and a power sensor 4, the power sensor is connected with the variable-pitch controller, the variable-pitch controller is provided with a speed controller and a power controller, the speed controller controls a given rotating speed, and the power controller controls given power.

Example 3:

the method for controlling the pitch of the hydraulic pitch device of the distributed wind turbine generator system according to the embodiment 1-2 comprises the following steps: firstly, before an engine is merged into a power grid, a speed controller carries out variable pitch control according to a rotating speed feedback signal of the engine, the blade of a wind wheel is determined to be in a standby or feathering position according to a rotating speed and a wind speed signal, a power controller acts after the engine is merged into the power grid, a power regulator is usually controlled by pi or pid, and a power error signal is subjected to pi operation to obtain a pitch angle position;

a power signal of the generator is input to the plc in an analog quantity form by a high-speed power transmitter, namely 0-10 v corresponds to 0-800 kw of power, a pitch angle feedback signal, namely 0-10 v corresponds to 0-90 degrees of pitch angle, is input to an analog input unit of the plc in an analog quantity form, and a hydraulic sensor is input in an analog quantity form;

when the wind speed is increased, the variable pitch hydraulic cylinder pushes the blades to rotate towards the increasing direction of the pitch angle, so that the wind energy absorbed by the blades is reduced, the wind wheel is maintained to operate within the range of rated rotating speed, when the wind speed is reduced, reverse operation is carried out, the power absorbed by the wind wheel is basically kept constant, and the blades are adjusted to the preset pitch more quickly and accurately;

when the wind turbine is in a shutdown state, the pitch angle is at a 90-degree position, the airflow does not generate torque to the blades, the pitch angle is reduced to 15 degrees from 90 degrees at a certain speed, if the wind speed reaches the grid-connected wind speed, the pitch angle is continuously reduced to a 3-degree generator and is connected with a power grid, and when the wind speed is less than the rated wind speed, the pitch angle is kept unchanged at 3 degrees;

when the wind speed is higher than the rated wind speed, the controller outputs-10V- +10V voltage to the proportional valve according to the power feedback signal, the direction and the size of the output flow of the proportional valve are controlled, the pitch angle of the blade is controlled by the pitch-variable hydraulic cylinder according to the flow and the direction output by the proportional valve, the output power is maintained near the rated power, and if a fault occurs or a shutdown command exists, the controller outputs a rapid feathering command, so that the wind turbine can be rapidly shut down;

the speed of propeller feeding or propeller withdrawing can be changed by changing the voltage of the hydraulic proportional valve, when a wind turbine fails or is in emergency shutdown, the electromagnetic valves j-b can be controlled to be closed, and the j-a and the j-c can be controlled to be opened, so that hydraulic oil in the pressure storage tank A can rapidly enter the variable pitch cylinder to push the blades to reach the feathering position of 90 degrees, the output power can be kept at the rated power by adjusting the pitch angle, and when a fault shutdown or emergency shutdown signal occurs, the electromagnetic valves j-a and j-c are controlled to be opened, and the j-b is controlled to be closed, so that the blades can be rapidly changed to the position of 90 degrees.