A Yaw Protection Method and System for a Wind Turbine Generator

Abstract

The present invention discloses a yaw protection method and system for a wind turbine generator. Substantially, the method is a yaw slip suppression method. When the yaw slip starts, a controllable DC braking current is input to the yaw motor through the yaw frequency converter, and an additional electromagnetic braking torque is provided by the yaw motor to suppress the slip in all directions to protect the yaw system, thereby effectively realizing yaw slip suppression, and the whole process is safe and reliable. The present invention provides an additional electromagnetic braking torque through the yaw frequency converter and the yaw motor, and the electromagnetic braking torque is controllable, which can effectively protect the yaw transmission mechanism.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power generation, and in particular to a yaw protection method and system for a wind turbine generator set. Background Art

[0002] At present, when a wind turbine generator set is in non-yaw standby, a hydraulic brake and an electromagnetic brake are generally used to brake the yaw system. In strong winds or sudden load changes, when the resistance of the yaw system is insufficient to balance the load, yaw slip (referred to as yaw slip) is likely to occur. Frequent yaw slip will gradually reduce the system resistance and ultimately cause wear and even damage to the yaw system. Summary of the Invention

[0003] The first object of the present invention is to overcome the deficiencies of the prior art and provide a safe and reliable yaw protection method for a wind turbine generator set, which can effectively suppress yaw slip.

[0004] The second object of the present invention is to provide a yaw protection system for a wind turbine generator set.

[0005] The first object of the present invention is achieved by the following technical solution: A yaw protection method for a wind turbine generator set, which is a yaw slip suppression method. When yaw slip starts, a controllable DC braking current is input to the yaw motor through the yaw frequency converter, and an additional electromagnetic braking torque is provided by the yaw motor to suppress slip in all directions to protect the yaw system, thereby effectively realizing yaw slip suppression.

[0006] Preferably, the yaw slip is the slip during yaw standby, and the suppression thereof is called slip suppression during yaw standby. The process is divided into slip angle judgment, frequency converter mode switching, DC braking output, and DC output control, as follows:

[0007] a1. Slip angle judgment: Determine that it is in the yaw standby state at this time, calculate the difference in the yaw encoder angle for each sampling period, and when the difference / period value is greater than the set slip threshold, confirm that the unit is in the slip state;

[0008] a2. Frequency converter mode switching: After the main controller confirms the slip state, issue a braking command through communication / DI signals;

[0009] a3. DC braking output: The yaw frequency converter outputs a DC voltage to form a DC braking current;

[0010] a4. DC output control: According to the feedback DC braking current and the torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage.

[0011] Preferably, the yaw slip is the slip during a yaw fault, and suppressing it is called yaw fault slip suppression. The process is divided into fault state judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows:

[0012] b1. Fault state judgment: Judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter fault state at this time;

[0013] b2. Frequency converter mode switching: The main controller issues a yaw frequency converter reset command and simultaneously issues a braking command through communication / DI signals;

[0014] b3. DC braking output: The yaw frequency converter outputs DC voltage starting from zero or a set value to form a DC braking current;

[0015] b4. DC output control: According to the feedback DC braking current and the torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage.

[0016] Preferably, the yaw slip includes slip during yaw standby and slip during yaw fault. Suppressing it is called yaw standby slip suppression and yaw fault slip suppression; where:

[0017] The process of yaw standby slip suppression is divided into slip angle judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows:

[0018] a1. Slip angle judgment: Judge that it is in the yaw standby state at this time. Subtract the yaw encoder angles of each sampling period. When the difference / period value is greater than the set slip threshold, confirm that the unit is in the slip state;

[0019] a2. Frequency converter mode switching: After the main controller confirms the slip state, issue a braking command through communication / DI signals;

[0020] a3. DC braking output: The yaw frequency converter outputs DC voltage to form a DC braking current;

[0021] a4. DC output control: According to the feedback DC braking current and the torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage;

[0022] The process of yaw fault slip suppression is divided into fault state judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows:

[0023] b1. Fault state judgment: Judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter fault state at this time;

[0024] b2. Inverter mode switching: The main controller issues a yaw inverter reset command and simultaneously issues a braking command through communication / DI signals.

[0025] b3. DC braking output: The yaw inverter outputs a DC voltage starting from zero or a set value to form a DC braking current.

[0026] b4. DC output control: Based on the feedback of the DC braking current and the torque protection threshold, the output of the yaw inverter is adjusted in real time to prevent overcurrent during braking or mechanical damage.

[0027] The second object of the present invention is achieved through the following technical solution: A yaw protection system for a wind turbine generator. When yaw slippage starts, a controllable DC braking current is input to the yaw motor through the yaw inverter, and an additional electromagnetic braking torque is provided by the yaw motor to suppress slippage in all directions to protect the yaw system, thereby effectively realizing yaw slippage suppression.

[0028] Preferably, it is a yaw slippage suppression system during standby, that is, the yaw slippage suppression it realizes is yaw slippage suppression during standby. This system is divided into four functional modules: a slip angle judgment module, a first inverter mode switching module, a first DC braking output module, and a first DC output control module, specifically as follows:

[0029] The slip angle judgment module is used to judge that it is in the yaw standby state at this time, and take the difference of the yaw encoder angles in each sampling period. When the difference / period value is greater than the set slip threshold, it is confirmed that the unit is in the slip state.

[0030] After the main controller confirms the slip state, the first inverter mode switching module issues a braking command through communication / DI signals.

[0031] The first DC braking output module outputs a DC voltage through the yaw inverter to form a DC braking current.

[0032] The first DC output control module adjusts the output of the yaw inverter in real time according to the feedback of the DC braking current and the torque protection threshold to prevent overcurrent during braking or mechanical damage.

[0033] Preferably, it is a yaw slippage suppression system during a yaw fault, that is, the yaw slippage suppression it realizes is yaw slippage suppression during a yaw fault. This system is divided into four functional modules: a fault state judgment module, a second inverter mode switching module, a second DC braking output module, and a second DC output control module, specifically as follows:

[0034] The fault state judgment module is used to judge that it is in the yaw state at this time and judge that it is in the yaw inverter fault state.

[0035] The second frequency converter mode switching module issues a yaw frequency converter reset command under the master controller, and at the same time issues a braking command through the communication / DI signal;

[0036] The second DC braking output module outputs a DC voltage starting from zero or a set value through the yaw frequency converter to form a DC braking current;

[0037] The second DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and the torque protection threshold to prevent overcurrent braking or mechanical damage.

[0038] Preferably, the system includes a slip suppression module during yaw standby and a slip suppression module during yaw failure; where:

[0039] The slip suppression module during yaw standby is divided into four functional modules: a slip angle judgment module, a first frequency converter mode switching module, a first DC braking output module, and a first DC output control module, specifically as follows:

[0040] The slip angle judgment module is used to judge that it is in the yaw standby state at this time, subtract the yaw encoder angles of each sampling period, and when the difference / cycle value is greater than the set slip threshold, confirm that the unit is in the slip state;

[0041] The first frequency converter mode switching module issues a braking command through the communication / DI signal after the master controller confirms the slip state;

[0042] The first DC braking output module outputs a DC voltage through the yaw frequency converter to form a DC braking current;

[0043] The first DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and the torque protection threshold to prevent overcurrent braking or mechanical damage;

[0044] The slip suppression module during yaw failure is divided into four functional modules: a fault state judgment module, a second frequency converter mode switching module, a second DC braking output module, and a second DC output control module, specifically as follows:

[0045] The fault state judgment module is used to judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter fault state;

[0046] The second frequency converter mode switching module issues a yaw frequency converter reset command under the master controller, and at the same time issues a braking command through the communication / DI signal;

[0047] The second DC braking output module outputs a DC voltage starting from zero or a set value through the yaw frequency converter to form a DC braking current;

[0048] The second DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and torque protection threshold to prevent overcurrent braking or mechanical damage.

[0049] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0050] 1. The present invention can effectively suppress yaw slip, and the whole process is safe and reliable.

[0051] 2. The present invention provides an additional electromagnetic braking torque through the yaw frequency converter and the yaw motor. The electromagnetic braking torque is controllable, which can effectively protect the yaw transmission mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 is the architecture diagram of the yaw system of the wind turbine generator.

[0053] Figure 2 is the standby slip timing diagram.

[0054] Figure 3 is the fault slip timing diagram.

[0055] Figure 4 is the architecture diagram of the yaw protection system of the wind turbine generator in Embodiment 4.

[0056] Figure 5 is the architecture diagram of the yaw protection system of the wind turbine generator in Embodiment 5.

[0057] Figure 6 is the architecture diagram of the yaw protection system of the wind turbine generator in Embodiment 6. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0058] The present invention will be further described in detail below in conjunction with the embodiments and the drawings, but the embodiments of the present invention are not limited thereto.

[0059] See Figure 1 As shown, the yaw system of the wind turbine generator includes: a main controller, a yaw frequency converter, a yaw motor, a yaw speed reducer, a yaw ring gear, a yaw motor brake, a yaw hydraulic brake, a yaw encoder, etc. The present invention discloses a yaw protection method for a wind turbine generator, which is essentially a yaw slip suppression method. When the yaw slip starts, a controllable DC braking current is input to the yaw motor through the yaw frequency converter, and an additional electromagnetic braking torque is provided by the yaw motor to suppress the slip in all directions to protect the yaw system, thereby effectively realizing the suppression of yaw slip.

[0060] Embodiment 1

[0061] The yaw slip addressed in this embodiment is the slip during yaw standby, and its suppression is called the slip suppression during yaw standby. The process is divided into slip angle judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows:

[0062] a1. Slip angle judgment: Judge that it is in the yaw standby state at this time, calculate the difference in the yaw encoder angle for each sampling period, and confirm that the unit is in the slip state when the difference / period value is greater than the set slip threshold;

[0063] a2. Frequency converter mode switching: After the main controller confirms the slip state, send a braking command through communication / DI signals;

[0064] a3. DC braking output: The yaw frequency converter outputs a DC voltage to form a DC braking current;

[0065] a4. DC output control: According to the feedback DC braking current and torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage.

[0066] Among them, the standby slip time sequence is shown in Figure 2 as follows.

[0067] Embodiment 2

[0068] The yaw slip addressed in this embodiment is the slip during yaw failure, and its suppression is called the slip suppression during yaw failure. The process is divided into failure state judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows:

[0069] b1. Failure state judgment: Judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter failure state;

[0070] b2. Frequency converter mode switching: The main controller sends a reset command to the yaw frequency converter and simultaneously sends a braking command through communication / DI signals;

[0071] b3. DC braking output: The yaw frequency converter starts to output a DC voltage from zero or a small value to form a DC braking current;

[0072] b4. DC output control: According to the feedback DC braking current and torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage.

[0073] Among them, the failure slip time sequence is shown in Figure 3 as follows.

[0074] Embodiment 3

[0075] The yaw slip addressed in this embodiment includes the slip during yaw standby and the slip during yaw failure, and its suppression is called the slip suppression during yaw standby and the slip suppression during yaw failure; among them:

[0076] The process of slip suppression during yaw standby is divided into slip angle judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows:

[0077] a1. Slip angle judgment: Determine that it is in the yaw standby state at this time, calculate the difference in the yaw encoder angle for each sampling period, and when the difference / period value is greater than the set slip threshold, confirm that the unit is in the slip state;

[0078] a2. Frequency converter mode switching: After the main controller confirms the slip state, send a braking command through communication / DI signals;

[0079] a3. DC braking output: The yaw frequency converter outputs a DC voltage to form a DC braking current;

[0080] a4. DC output control: According to the feedback DC braking current and torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage.

[0081] The process of slip suppression during yaw failure is divided into failure state judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows:

[0082] b1. Failure state judgment: Determine that it is in the yaw state at this time and judge that it is in the yaw frequency converter failure state;

[0083] b2. Frequency converter mode switching: The main controller issues a reset command for the yaw frequency converter and simultaneously sends a braking command through communication / DI signals;

[0084] b3. DC braking output: The yaw frequency converter starts to output a DC voltage from zero or a small value to form a DC braking current;

[0085] b4. DC output control: According to the feedback DC braking current and torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage.

[0086] Among them, the standby slip time sequence is shown in Figure 2 as shown, and the fault slip time sequence is shown in Figure 3 as shown.

[0087] Embodiment 4

[0088] This embodiment discloses a yaw protection system for a wind turbine generator, which is essentially a slip suppression system during yaw standby, that is, the yaw slip suppression it realizes is the slip suppression during yaw standby, as shown in Figure 4 as shown. This system is divided into four functional modules: a slip angle judgment module, a first frequency converter mode switching module, a first DC braking output module, and a first DC output control module, which are specifically as follows:

[0089] The slip angle judgment module is used to judge that it is in the yaw standby state at this time, calculate the difference between the yaw encoder angles of each sampling period, and confirm that the unit is in the slip state when the difference / period value is greater than the set slip threshold;

[0090] After the main controller confirms the slip state, the first frequency converter mode switching module issues a braking command through communication / DI signals;

[0091] The first DC braking output module outputs a DC voltage through the yaw frequency converter to form a DC braking current;

[0092] The first DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and the torque protection threshold to prevent overcurrent braking or mechanical damage.

[0093] Among them, the standby slip timing is shown in Figure 2 as shown.

[0094] Embodiment 5

[0095] This embodiment discloses a yaw protection system for a wind turbine generator, which is essentially a slip suppression system during yaw faults, that is, the yaw slip suppression achieved is the slip suppression during yaw faults, as Figure 5 shown, this system is divided into four functional modules: a fault state judgment module, a second frequency converter mode switching module, a second DC braking output module, and a second DC output control module, specifically as follows:

[0096] The fault state judgment module is used to judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter fault state;

[0097] When the main controller issues a yaw frequency converter reset command, the second frequency converter mode switching module issues a braking command through communication / DI signals at the same time;

[0098] The second DC braking output module outputs a DC voltage starting from zero or a small value through the yaw frequency converter to form a DC braking current;

[0099] The second DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and the torque protection threshold to prevent overcurrent braking or mechanical damage.

[0100] Among them, the fault slip timing is shown in Figure 3 as shown.

[0101] Embodiment 6

[0102] This embodiment discloses a yaw protection system for a wind turbine generator, as Figure 6As shown, it includes a slip suppression module during yaw standby and a slip suppression module during yaw failure; among which:

[0103] The slip suppression module during yaw standby is divided into four functional modules: a slip angle judgment module, a first frequency converter mode switching module, a first DC braking output module, and a first DC output control module, specifically as follows:

[0104] The slip angle judgment module is used to judge the yaw standby state at this time, subtract the yaw encoder angles of each sampling period, and when the difference / period value is greater than the set slip threshold, it is confirmed that the unit is in a slip state;

[0105] After the main controller confirms the slip state, the first frequency converter mode switching module issues a braking command through communication / DI signals;

[0106] The first DC braking output module outputs a DC voltage through the yaw frequency converter to form a DC braking current;

[0107] The first DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and the torque protection threshold to prevent overcurrent braking or mechanical damage.

[0108] The slip suppression module during yaw failure is divided into four functional modules: a failure state judgment module, a second frequency converter mode switching module, a second DC braking output module, and a second DC output control module, specifically as follows:

[0109] The failure state judgment module is used to judge the yaw state at this time and judge the yaw frequency converter failure state at this time;

[0110] When the main controller issues a yaw frequency converter reset command, the second frequency converter mode switching module issues a braking command through communication / DI signals at the same time;

[0111] The second DC braking output module outputs a DC voltage from zero or a small value through the yaw frequency converter to form a DC braking current;

[0112] The second DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and the torque protection threshold to prevent overcurrent braking or mechanical damage.

[0113] Among them, the standby slip time sequence is shown in Figure 2 as shown, and the failure slip time sequence is shown in Figure 3 as shown.

[0114] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present invention shall be equivalent substitution methods and are all included in the protection scope of the present invention.

Claims

1. A yaw protection method for a wind turbine generator, characterized in that: It is a yaw slip suppression method. When yaw slip starts, a controllable DC braking current is input to the yaw motor through the yaw frequency converter, and an additional electromagnetic braking torque is provided by the yaw motor to suppress slips in all directions to protect the yaw system, thereby effectively achieving yaw slip suppression. Among them, the yaw slip is the slip during yaw standby, or the slip during yaw failure, or includes both the slip during yaw standby and the slip during yaw failure. For the slip during yaw standby, suppressing it is called yaw slip suppression during yaw standby. The process is divided into slip angle judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows: a1. Slip angle judgment: Judge that it is in the yaw standby state at this time, calculate the difference in the yaw encoder angle for each sampling period, and when the difference / period value is greater than the set slip threshold, confirm that the unit is in the slip state. a2. Frequency converter mode switching: After the main controller confirms the slip state, send a braking instruction through communication / DI signal. a3. DC braking output: The yaw frequency converter outputs a DC voltage to form a DC braking current. a4. DC output control: According to the feedback DC braking current and torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage. For the slip during yaw failure, suppressing it is called yaw slip suppression during yaw failure. The process is divided into failure state judgment, frequency converter mode switching, DC braking output, and DC output control, which are specifically as follows: b1. Failure state judgment: Judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter failure state. b2. Frequency converter mode switching: The main controller issues a yaw frequency converter reset instruction and at the same time sends a braking instruction through communication / DI signal. b3. DC braking output: The yaw frequency converter starts to output a DC voltage from zero or a set value to form a DC braking current. b4. DC output control: According to the feedback DC braking current and torque protection threshold, adjust the output of the yaw frequency converter in real time to prevent overcurrent braking or mechanical damage.

2. A yaw protection system for a wind turbine generator, characterized in that: It is used to implement the yaw protection method of the wind turbine generator set described in claim 1. When yaw slip starts, a controllable DC braking current is input to the yaw motor through the yaw frequency converter, and an additional electromagnetic braking torque is provided by the yaw motor to suppress slips in all directions to protect the yaw system, thereby effectively achieving yaw slip suppression.

3. A yaw protection system for a wind turbine generator set according to claim 2, characterized in that, It is a yaw slip suppression system during yaw standby, that is, the yaw slip suppression it realizes is the yaw slip suppression during yaw standby. This system is divided into four functional modules: slip angle judgment module, first frequency converter mode switching module, first DC braking output module, and first DC output control module, which are specifically as follows: The slip angle judgment module is used to judge that it is in the yaw standby state at this time, calculate the difference in the yaw encoder angle for each sampling period, and when the difference / period value is greater than the set slip threshold, confirm that the unit is in the slip state. The first frequency converter mode switching module sends a braking instruction through communication / DI signal after the main controller confirms the slip state. The first DC braking output module outputs a DC voltage through the yaw frequency converter to form a DC braking current. The first DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and torque protection threshold to prevent overcurrent braking or mechanical damage.

4. A yaw protection system for a wind turbine generator set according to claim 2, characterized in that: It is a yaw fault slip suppression system, that is, the yaw slip suppression it realizes is the yaw fault slip suppression. This system is divided into four functional modules: a fault state judgment module, a second frequency converter mode switching module, a second DC braking output module, and a second DC output control module, which are specifically as follows: The fault state judgment module is used to judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter fault state at this time; The second frequency converter mode switching module issues a yaw frequency converter reset command from the main controller and issues a braking command through the communication / DI signal at the same time; The second DC braking output module outputs a DC voltage from zero or a set value through the yaw frequency converter to form a DC braking current; The second DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and torque protection threshold to prevent overcurrent braking or mechanical damage.

5. A yaw protection system for a wind turbine generator set according to claim 2, characterized in that: It includes a yaw standby slip suppression module and a yaw fault slip suppression module; among them: The yaw standby slip suppression module is divided into four functional modules: a slip angle judgment module, a first frequency converter mode switching module, a first DC braking output module, and a first DC output control module, which are specifically as follows: The slip angle judgment module is used to judge that it is in the yaw standby state at this time, subtract the yaw encoder angles of each sampling period, and when the difference / period value is greater than the set slip threshold, it is confirmed that the unit is in the slip state; The first frequency converter mode switching module issues a braking command through the communication / DI signal after the main controller confirms the slip state; The first DC braking output module outputs a DC voltage through the yaw frequency converter to form a DC braking current; The first DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and torque protection threshold to prevent overcurrent braking or mechanical damage; The yaw fault slip suppression module is divided into four functional modules: a fault state judgment module, a second frequency converter mode switching module, a second DC braking output module, and a second DC output control module, which are specifically as follows: The fault state judgment module is used to judge that it is in the yaw state at this time and judge that it is in the yaw frequency converter fault state at this time; The second frequency converter mode switching module issues a yaw frequency converter reset command from the main controller and issues a braking command through the communication / DI signal at the same time; The second DC braking output module outputs a DC voltage from zero or a set value through the yaw frequency converter to form a DC braking current; The second DC output control module adjusts the output of the yaw frequency converter in real time according to the feedback DC braking current and torque protection threshold to prevent overcurrent braking or mechanical damage.

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