GB/T 47557-2026Wind energy generation systems - Technical specification for wind turbine braking systems (English PDF)

5.1.1 Control System Design Requirements

5.1.1.1 The design of the braking system shall comply with the working load requirements in Table 2 of GB/T 18451.1-2022.

5.1.1.2 The braking system shall be equipped with at least two independent braking devices, typically consisting of a pneumatic braking device and a mechanical braking device. The system is complete, with the pneumatic braking device serving as the primary braking stage and the mechanical braking device as the secondary braking stage. Each braking stage can operate independently or be used during engagement. Coordinate actions in terms of timing or entry speed.

5.1.1.3 The braking system should be equipped with at least one wind turbine locking device, which should be located close to the hub. If this cannot be achieved, a portable locking device should be provided. The wind turbine locking device can be installed at any time when needed. Even when the mechanical braking device is in the open state during wind turbine locking, it still reliably ensures the wind turbine's stability. It does not rotate.

5.1.1.4 During the braking process from the operating state to the shutdown of the wind turbine generator set, the first-level brake should be engaged first to decelerate the wind turbine. When the brake disc rotates... Secondary braking can be engaged after the following limiting conditions (including but not limited to) are met.

---Maximum braking temperature limit. To prevent brake fade and failure caused by excessively high temperatures in the friction pairs, a maximum braking temperature limit should be set. Thermal balance calculation and verification at high speeds; when the brake pads are made of organic composite materials, the braking temperature of the friction pair is usually controlled at... Below.200°C (instantaneous value not exceeding 250°C); when the brake pads are made of sintered metal material, the braking temperature of the friction pair is usually... Keep it below 650°C (instantaneous value not higher than 900°C).

---Limitation of Braking Spark Stream. To avoid the risk of fire caused by continuous spark streams generated by the friction pair, spark testing should be performed at the target braking speed. Beam verification.

5.1.1.5 The braking system shall have fail-safe protection functionality. In the event of a major fault, the braking system shall be able to bring the wind turbine generator to a safe braking position. Dynamic state.

5.1.1.6 The braking system shall be designed with different operating modes, including at least normal braking, rapid braking, emergency braking, and... The wind turbine locking method should be specified, along with the conditions for engaging various operating modes and the sequence for engaging the braking devices; the emergency braking method should have a high efficiency. Priority should be shifted from normal braking to emergency braking, and even during normal braking, it can transition to emergency stop as needed. model.

5.1.1.7 The braking system shall adopt a redundant control method, and shall be designed with at least normal control logic and safety control logic, and various control methods shall be specified. The triggering conditions for control logic; the priority level of security control logic should be higher than that of normal control logic.

5.1.1.8 The braking system shall have both manual operation mode and automatic control mode. These two operation modes shall be independent of each other. Manual operation shall have... Priority is set, and the operating mode can be switched at any time as needed; different operating modes cannot be activated simultaneously under any conditions.

5.1.1.9 The braking system shall have a complete system self-protection function, and the system shall be able to protect itself in the event of overcurrent, overheating and overpressure.

5.1.2 Other design requirements

5.1.2.1 The rated static braking torque of the braking system should be greater than the minimum static braking torque required by the wind turbine generator set. The braking torque should be determined based on extreme operating conditions. The rated dynamic braking torque of the braking system should be greater than the minimum dynamic braking torque required by the wind turbine generator set. The dynamic braking torque is less than the maximum allowable braking torque of the wind turbine generator set.

5.1.2.2 The high-strength fasteners used in the braking system and its components shall meet the requirements of GB/T 33628.

5.1.2.3 The selection and design of the drive unit of the braking system should facilitate the automatic control function of the wind turbine generator braking system.

5.1.2.4 Important components of the braking system should adopt a safety redundancy design; a single component failure should not trigger a failure in more than one braking device. This can lead to a breakdown in security features, resulting in the loss of the entire security function.

5.1.2.5 The braking speed and acceleration capabilities of the pneumatic braking device shall meet the requirements of normal braking, rapid braking and emergency braking.

5.1.2.6 All sensor signals of the braking system can be obtained by the control system.

5.2 Functional and Performance Requirements

5.2.1 Manual braking function In manual control mode, the system should be able to read system status information and perform parameter settings and calibrations. In manual control mode, it should be able to perform air braking and mechanical braking operations respectively, so as to decelerate and stop the wind turbine and maintain the stopped state. In manual control mode, if a system failure occurs, the braking system should be able to keep the wind turbine shaft or wind turbine in its original position until the failure is resolved.

5.2.2 Automatic braking function In automatic control mode, the braking system should be able to accept commands from the control system to brake.

5.2.3 Normal braking function Normal braking should ensure a smooth transition of the wind turbine generator to a shutdown state. The braking force should be applied gradually to avoid damage during the braking process. The equipment caused damage. Normal braking should be able to be activated by control function commands, manual operation commands, and fail-safe function commands. When normal braking is activated, the pneumatic braking device brakes at normal speed. Under safe conditions for the unit, the mechanical braking device may not be engaged. brake.

5.2.4 Rapid braking function Rapid braking should ensure that the wind turbine generator can transition to a shutdown state quickly and controllably, and avoid damage to the equipment due to excessive speed. Rapid braking should be able to be activated by manual operation commands and fail-safe commands. When rapid braking is activated, the pneumatic braking device applies rapid braking, while the mechanical braking device may not be involved in braking if the unit is safe.

5.2.7 Failure Protection Function

5.2.7.1 High and Low Temperature Protection. When the internal temperature of the braking system is too low/high, the braking system should be able to automatically brake to keep the wind turbine generator set in a safe position. Safe braking state.

5.2.7.2 Backup Power Supply Failure. When the voltage, temperature, or capacity of the backup power supply to the braking system exceeds limits, the braking system may still fail to function properly. The wind turbine generator is in a safe braking state.

5.2.7.3 Watchdog Failure. After a watchdog failure is triggered, the system should be able to brake normally, bringing the wind turbine generator set into a safe braking state.

5.2.7.4 Lightning protection fault. The surge protection device in the power supply circuit should be able to brake normally in case of a fault, so that the wind turbine generator set is in a safe braking state. The driver failure is as follows (5.2.7.10).

a) In the event of a motor failure in a hydraulically driven braking system, the system should be able to implement rapid braking via an accumulator to bring the wind turbine generator to a safe braking position. Dynamic state.

b) In the event of a motor failure in the electromagnetically driven braking system, all blades should be able to feather to the braking position, or the faulty blade should engage the brake, and the other blades should engage the brake. The propeller blades should be feathered to the braking position to put the wind turbine generator in a safe braking state.

c) If one blade of the variable pitch turbine jams, the other blades and the mechanical braking device should be able to apply emergency braking to ensure the wind turbine generator is in a safe condition. Braking state.

d) If one tip spoiler of a fixed-pitch wind turbine becomes stuck, the other tip spoilers and mechanical braking devices should be able to apply emergency braking to allow the wind turbine to generate electricity. The unit is in a safe braking state.

e) In the event of a mechanical braking device failure, the variable pitch wind turbine should be able to idle using air braking. Status; In the event of a fault in a constant pitch wind turbine generator, if one brake fails to operate, the other brake can work in conjunction with the blade tip disturbance. The flow meter stops the wind turbine.

5.2.7.11 Locking Failure. In non-locking mode, if the locking device loses its unlocking signal, the braking system can implement the braking strategy according to the host control policy. Appropriate braking.

5.2.8 Communication Interface Requirements The communication interface of the braking system shall comply with the provisions of

5.2.9 in GB/T 32077-2025.

5.2.9 Performance Requirements

5.2.9.1 The braking system shall operate quickly and reliably, with a response time not exceeding 0.2s.

5.2.9.2 The mechanical braking device should be able to maintain the clamping force for no less than 2 minutes under maximum clamping force, and the pneumatic braking device should be able to maintain the clamping force for no less than 2 minutes under maximum load torque. The continuous operating time should not be less than 3 seconds, and no damage or harmful deformation should occur.

5.2.9.3 At room temperature, the mechanical braking device should be able to withstand at least 5000 opening and closing tests under the applied clamping force, and the pneumatic braking device should be able to continuously meet the required standards. The load test should not be less than 72 hours, and no damage or harmful deformation should occur.

5.2.9.4 The tolerance of the rated power test value of the mechanical braking device shall not exceed ±10% of the design value.

5.2.9.5 When the mechanical braking device is not braking, the release clearance of the friction pair should not be less than 1mm, except for electromagnetic disc brakes.

5.2.9.6 The backup power source for the braking system should be able to guarantee at least one emergency braking operation, and under defined maintenance conditions, the mechanical braking device should be able to... After the action is performed, the wind turbine should be able to come to a complete stop for at least 1 hour.

5.2.9.7 Electromagnetic compatibility shall comply with the provisions of

5.3.1 in GB/T 32077-2025.

5.2.9.8 The insulation performance shall comply with the requirements of

5.3.2 in GB/T 32077-2025.

5.2.9.9 The mechanical properties shall conform to the requirements of

5.3.3 in GB/T 32077-2025.

5.2.9.10 The enclosure protection (IP code) shall comply with the provisions of

5.3.4 in GB/T 32077-2025.

5.3.1 Pneumatic Braking Device

5.3.1.1 The pneumatic braking device should be able to limit the wind turbine speed within a safe range or allow the wind turbine to idle without having to bring it to a complete stop.

5.3.1.2 The electrical control of the pneumatic braking device shall comply with the provisions of GB/T 18451.1-2022 and NB/T 31017.

5.3.1.3 The pneumatic brake device shall have a fail-safe function, preventing damage to the blades of the variable pitch blades and the tip disturbance of the fixed pitch blades when the drive unit loses power. The impeller should be able to rotate to the braking position under the action of aerodynamic force, centrifugal force or spring force, limiting the speed of the impeller to a safe range.

5.3.1.4 Pneumatic braking devices should have the ability to maintain the braking position when the machine stops. Variable pitch blades and fixed pitch blade tip spoilers should not... When the vehicle leaves the set braking position under the action of wind torque, its holding torque should meet the design requirements of the braking system; during typhoons or hurricanes... In this case, variable pitch turbine units can be equipped with blade locking devices to keep the blades in the braking position.

5.3.1.5 The sampling period for the blade angle of the variable pitch should not exceed 25ms.

5.3.2 Mechanical braking device

5.3.2.1 The mechanical braking device acting on the wind turbine or drive shaft should be able to ensure that the wind turbine is in a stopped state.

5.3.2.2 The control of the mechanical braking device should be able to meet the requirements of the braking system loading mode.

5.3.2.3 The rated static braking torque and rated dynamic braking torque shall meet the design requirements of the braking system.

5.3.2.4 The determination of the maximum and minimum braking torque should be based on the brake working pressure, friction pair temperature rise, wear, and braking impact load. Based on factors such as the lotus and other conditions.

5.3.2.5 The friction pairs of the mechanical braking device shall not be subject to the ingress of rain, snow, sand, or contamination by oil.

5.3.2.6 Mechanical braking devices shall be protected by splash guards to prevent operators from accidentally coming into contact with the rotating brake disc.

5.3.2.7 It should have wear compensation function to ensure that effective braking can still be performed after the friction material is worn within a certain range.

5.3.2.8 The selection of friction material composition should take into account the impact of wear debris on surrounding equipment. Friction materials should not contain harmful substances such as asbestos. Installation... In mechanical braking devices near permanent magnet generators, the friction material should not contain conductive metallic materials.

5.3.2.9 The braking device and exposed materials within the temperature-affected zone of the brake system shall be non-flammable. If this cannot be achieved, self-extinguishing materials shall be used. Fire-resistant materials and smokeless or low-smoke materials shall meet the requirements of Class A and Class B1(B) in GB 8624-2012.

6.1 Test Conditions

6.1.1 The wind speed at the test site should be within the range of 2 m/s to the rated wind speed, and complex terrain and obstacles should be avoided.

6.1.2 Experiments should avoid being conducted under special climatic conditions (such as rain, snow, ice, etc.).

6.1.3 The instruments and meters used for testing shall comply with the provisions of Chapter 6 of GB/T 13729-2019 and Chapter 3 of JB/T 5777.3-2002.

6.1.4 A structural and visual inspection should be conducted before the test.

6.2 Functional and Performance Tests

6.2.1 Manual Braking Function Test The manual braking function test shall be conducted according to the following procedure.

a) When the wind turbine generator is running normally, set the operating mode to manual mode, first manually engage the pneumatic brake, then engage the mechanical brake. The system records the response of each braking device.

b) When the wind turbine generator is shut down, set the operation mode to manual mode, perform jogging operation on each braking device, and make corresponding adjustments. Record; perform manual calibration of blade (or blade tip) angle sensors, position sensors, etc.

c) If the pitch control system uses speed control or position control, then each blade is manually controlled for speed or position individually. Verification.

6.2.2 Automatic braking function test The automatic braking function test shall be conducted according to the following procedure.

a) Communication Test. After normal power-on, observe the internal workings of the braking system via the human-machine interface or PC. The braking system and the wind turbine generator set... The control systems should communicate normally;

b) Automatic braking. During normal operation of the wind turbine generator set, braking commands are issued through the human-machine interface of the wind turbine generator set control system. Order, observe and record the response of the braking system.

6.2.3 Normal braking test During normal operation of the wind turbine generator set, the control system issues a normal shutdown command, observes and records the braking process status and total braking. Time, unit vibration acceleration, hydraulic pressure (if applicable), and braking torque loading method; observe and record the blades or... The braking speed and position of the blade tip spoiler; if mechanical braking is triggered, observe and record the braking speed, braking temperature and braking spark.

6.2.4 Rapid braking test During normal operation of the wind turbine generator set, manually operate the control system to issue a rapid shutdown command, observe and record its braking process. Observe and record the state, total braking time, unit vibration acceleration, hydraulic pressure (if applicable), and braking torque loading method; observe and record the pneumatic braking device. The braking speed and position of the blades or blade tip spoilers; if mechanical braking is triggered, observe and record the braking speed, braking temperature, and braking force. spark.

6.2.5 Emergency Braking Test During operation at wind speeds above rated power without additional malfunctions, press the emergency stop button, observe and record the braking process and its status. Total braking time, unit vibration acceleration, hydraulic pressure (if applicable), and braking torque loading method; observe and record the pneumatic braking device. Braking speed and braking position of blades or blade tip spoilers; observe and record braking speed, braking temperature and braking sparks of mechanical braking devices. After the mechanical braking device is activated, the time it takes for the wind turbine to come to a complete stop is detected and recorded.

6.2.6 Wind turbine locking test When the wind turbine generator is in maintenance mode, perform a rotor locking operation; coordinate with the mechanical braking device or turning gear mechanism to lock and unlock. Lock the wind turbine, check and record the locking and unlocking times; check for any rotational displacement of the wind turbine while it is locked. For units requiring single-blade hoisting, detect and record the rotor locking position.

6.2.7 Failure Protection Function Test

6.2.7.1 High and Low Temperature Protection Adjust the temperature sensor's sampling value to exceed the high/low temperature alarm setpoint of the control system, observe and record the alarm status and braking system. The system's response.

6.2.7.2 Backup power supply failure The backup power failure test shall be conducted according to the following procedure.

a) Change the sampling value of the backup power supply cabinet temperature sensor or change the temperature over-limit threshold so that the actual sampling temperature exceeds the threshold, and observe. It also records the alarm status and the braking system response;

b) Disconnect the voltage input terminal of the backup power supply voltage monitoring module or increase the undervoltage setting value so that the actual sampled voltage value is lower than the undervoltage setting. Press the set value, observe and record the fault alarm status and the braking system response.

6.2.7.3 Watchdog Failure Trigger the watchdog output signal, observe and record the fault alarm status and the braking system response.

6.2.7.4 Lightning protection fault Disconnect the feedback signal of the surge protection device in the power supply circuit, observe and record the fault alarm status and the response of the braking system.

6.2.7.5 Braking system sensor failure Braking system sensor failure testing includes...

6.2.7.7 Communication failure Disconnect the communication line and observe and record the fault alarm status and the braking system response.

6.2.7.8 Power supply failure Power failure testing includes.

---For hydraulically driven braking system units, disconnect one phase of a variable pitch motor, observe and record the fault alarm status and braking system status. System response;

---For electromagnetically driven variable pitch turbine units, disconnect one phase of a variable pitch motor, observe and record the fault alarm status and braking system. The response.

6.2.7.9 Safety Protection At wind speeds exceeding rated power, disconnect the wind turbine's hardware safety chain (this should at least trigger rotor overspeed and vibration faults), and observe and... Record whether the braking system applied emergency braking.

6.2.7.10 Driver Failure Drive failure testing includes...

---Grid Fault Ride Test. During normal operation of the wind turbine generator set, a grid simulation system is used to input data conforming to GB/T 19963.1- In accordance with the requirements of 9.2,

6.2.9 Performance Test

6.2.9.1 Response Time The time from receiving a command to starting to act is measured for pneumatic and mechanical braking devices.

6.2.9.2 Maximum Load Test The maximum load test for mechanical braking devices takes the spindle disc brake test as an example; other tests should be conducted similarly. The maximum load of the spindle disc brake... The load test shall be performed in accordance with the method in

6.2.4 of NB/T 31023-2021. The maximum load test of the pneumatic braking device takes the pitch system test as an example, and other tests should be performed in the same manner; the maximum load test of the pitch system is conducted according to... Perform the procedure according to the method in section 6.3.3.3.3 of GB/T 32077-2025.

6.2.9.3 Stability Test The stability test of mechanical braking devices takes the spindle disc brake test as an example; other tests should be conducted in the same manner. The test shall be performed in accordance with the method in

6.2.5 of NB/T 31023-2021. The stability test of the pneumatic braking device takes the variable pitch system test as an example, and other tests should be conducted in the same manner; the stability test of the variable pitch system should be performed according to... The method specified in 6.3.3.3.4 of GB/T 32077-2025 shall be followed.

6.2.9.4 Braking force test The braking force test of mechanical braking devices takes the spindle disc brake test as an example; other tests should be performed similarly. The braking force test of the spindle disc brake... The test shall be performed in accordance with the method in

6.2.1 of NB/T 31023-2021.

6.2.9.5 Gate opening gap detection When the mechanical braking device is not braking, the clearance of the friction pair is checked with a feeler gauge and the value of the release clearance is recorded.

6.2.9.6 Backup power source braking test When the power grid is cut off at wind speeds above rated power, observe and record the braking process and the wind turbine's braking status after the mechanical braking device is activated. Maintain a complete stop time.

6.2.9.7 Electromagnetic compatibility test Electromagnetic compatibility testing shall be performed in accordance with the method in

6.3.1 of GB/T 32077-2025.

6.2.9.8 Insulation performance test The insulation performance test shall be performed in accordance with the method in

6.3.2 of GB/T 32077-2025.

6.2.9.9 Mechanical property test Mechanical performance tests shall be performed in accordance with the method in

7.2 Type Testing

7.2.1 A type test shall be conducted on a product under any of the following circumstances.

a) During product type certification;

b) If, after normal production begins, there are significant changes in structure, materials, components, or processes that may affect product performance;

c) When there is an unacceptable deviation between the sampling inspection results and the type test results;

d) When production resumes after a period of shutdown exceeding the prescribed time limit;

e) Other requirements (inspection items shall be in accordance with the relevant regulations).

7.2.2 The type test items shall comply with the provisions of Table 1.

7.2.3 The sampling quantity for the product is one set of braking system, and it will not be grouped during inspection.

7.2.4 The sample shall meet all the requirements specified in Chapter

5.One adjustment to adjustable parts is permitted during inspection; otherwise, no further adjustments are allowed. Replace the components.

7.3 Factory Inspection

7.3.1 Each product shall undergo factory inspection before leaving the factory.

7.3.2 The factory inspection items shall conform to the provisions of Table

1.If all inspection items are qualified, the factory inspection shall be deemed qualified.

8.1 Packaging

8.1.1 The packaging of the product shall comply with the provisions of GB/T 13384.

8.1.2 Before packaging, the movable parts of the product should be secured.

8.1.3 Except for products with waterproof function, each product shall be wrapped with waterproof material and then placed in a packaging box with a certain shockproof capability.

8.1.4 Product-as-a-product documents, accessories, and consumable parts shall be packaged and supplied together in accordance with the specifications in the instruction manual.

8.2 Transportation Packaged indoor products must meet the requirements of section

4.1 regarding extreme temperatures and relative humidity during transportation. Product transportation process... During transport, there should be no severe vibration, impact, or inversion. Any special requirements for certain components during transport should be specified so that appropriate measures can be taken.

8.3 Storage The packaged product should be stored at a temperature and humidity that meet the requirements of 4.1, and should be stored in an environment free from corrosive, flammable, and explosive substances. Indoor storage of sexually explicit substances. Long-term storage...