An alternating current (ac) variable pitch system

Abstract

The utility model discloses an alternating current variable pitch system, including three integrated alternating current drivers, three groups of super capacitor module and three alternating current permanent magnet synchronous motors, three integrated alternating current drivers are electrically connected cabin main controller, and integrated alternating current driver has integrated pitch controller, pitch driver and capacitor charger, and integrated alternating current driver is built -in with brake resistance, three groups of super capacitor module are electrically connected three integrated alternating current drivers respectively, three alternating current permanent magnet synchronous motors are electrically connected three integrated alternating current drivers respectively, in the utility model, after direct current variable pitch motor changes into alternating current permanent magnet synchronous motor, can fundamentally avoid carbon deposit and carbon brush wear and tear problem, and is favorable to prolonging the service life of bearing, simultaneously, integrated alternating current driver can reduce intermediate link failure point after integration, namely is favorable to reducing failure rate, in addition, brake resistance can consume the inertia energy generated in the working process, to avoid the harm brought about by inertia energy.

Description

Technical Field

[0001] This utility model belongs to the field of wind turbine pitch technology, and in particular relates to an AC pitch system. Background Technology

[0002] Most wind turbines are equipped with DC pitch systems. A DC pitch system includes a DC pitch motor and a battery, as well as a separately located pitch controller, pitch driver, and pitch charger for charging the battery.

[0003] However, due to the frequent braking and rotational movements of the DC pitch system, carbon buildup on the carbon brushes and bearing damage in the DC pitch motor are common. This leads to increased load and abnormally high current in the DC pitch motor, potentially causing burnout of the DC pitch motor, driver, and control circuit. Furthermore, the DC pitch system involves numerous components, resulting in a relatively large installation space required within the corresponding cabinets. Utility Model Content

[0004] To overcome the shortcomings of existing technologies, this utility model provides an AC pitch system that can reduce the failure rate and the installation space required.

[0005] The objective of this utility model is achieved through the following technical solution: An AC pitch system comprising: Three integrated AC drives are electrically connected to the nacelle main controller. Each integrated AC drive integrates a pitch controller, a pitch driver, and a capacitor charger. The integrated AC drive also has a built-in braking resistor. Three sets of supercapacitor modules, each electrically connected to one of three integrated AC drivers; Three AC permanent magnet synchronous motors are electrically connected to three integrated AC drives.

[0006] Furthermore, the integrated AC driver incorporates a filter and a switching power supply.

[0007] Furthermore, the AC pitch system includes a first temperature sensor for detecting the temperature around the integrated AC drive, the first temperature sensor being electrically connected to the integrated AC drive.

[0008] Furthermore, the AC pitch system includes a second temperature sensor for detecting the temperature around the supercapacitor module, the second temperature sensor being electrically connected to an integrated AC driver.

[0009] Furthermore, the AC pitch system includes three brakes, each electrically connected to one of the three integrated AC drives.

[0010] Furthermore, the AC pitch system includes three main limit switches and three redundant limit switches. The three main limit switches are electrically connected to three integrated AC drives, and the three redundant limit switches are electrically connected to three integrated AC drives, respectively.

[0011] Furthermore, power and signal lines are provided between the three integrated AC drives and the cabin main controller.

[0012] Furthermore, CANopen communication lines are provided between the two integrated AC drives and between the integrated AC drives and the cabin main controller.

[0013] Furthermore, a communication relay controller is provided on the CANopen communication line between the integrated AC drive and the cabin main controller; and / or a communication relay controller is provided on the signal line between the integrated AC drive and the cabin main controller. Furthermore, a motor power line and a motor feedback line for feeding back temperature information within the AC permanent magnet synchronous motor are provided between the integrated AC drive and the AC permanent magnet synchronous motor.

[0014] The beneficial effects of this utility model are as follows: Replacing the DC pitch motor with an AC permanent magnet synchronous motor can fundamentally avoid carbon buildup and carbon brush wear problems, and help extend the service life of the bearings. At the same time, the integration of the AC drive can reduce intermediate failure points, which helps to reduce the failure rate and reduce the installation space occupied. In addition, the braking resistor can consume the inertial energy generated during operation, so as to avoid the inertial energy from damaging the integrated AC drive or even the entire wind turbine. Attached Figure Description

[0015] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings. Wherein: Figure 1 A system diagram of this utility model is shown; Figure 2 The diagram shows the electrical connections of the integrated AC driver in this invention. In the accompanying drawings, the same parts use the same reference numerals. The drawings are not to scale.

[0016] Figure label: 1. Cabin main controller; 2. Slip ring system; 3. Communication relay controller; 4. Integrated AC driver; 5. Supercapacitor module; 6. AC permanent magnet synchronous motor; 7. First temperature sensor; 8. Second temperature sensor; 9. Braking resistor. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings.

[0018] This utility model provides an AC pitch system, such as Figure 1 and Figure 2 As shown, it includes: Three integrated AC drives 4 are electrically connected to the nacelle main controller 1 via a slip ring system 2. The integrated AC drive 4 integrates a pitch controller, a pitch drive and a capacitor charger. The integrated AC drive 4 has a built-in braking resistor 9. Three sets of supercapacitor modules 5 are electrically connected to three integrated AC drivers 4 respectively. The supercapacitor modules 5 serve as backup power sources. Each supercapacitor module 5 consists of three supercapacitors. The integrated AC drivers 4 charge the three supercapacitors. Three AC permanent magnet synchronous motors 6 are electrically connected to three integrated AC drivers 4 respectively. The power supply for the AC permanent magnet synchronous motors 6 is three-phase AC + PE.

[0019] Understandably, after the DC pitch motor is replaced with the AC permanent magnet synchronous motor 6, the AC permanent magnet synchronous motor 6 achieves energy conversion through electromagnetic induction, eliminating the need for carbon brushes to contact the commutator. This fundamentally avoids problems such as carbon buildup, electrical sparks, and carbon brush wear, and helps extend the service life of the bearings. At the same time, the integration of the integrated AC drive 4 reduces intermediate failure points, which helps lower the failure rate and reduces the installation space required. In addition, the braking resistor 9 can dissipate the inertial energy generated during operation, thus preventing the inertial energy from harming the integrated AC drive 4 or even the entire wind turbine.

[0020] It should be noted that, compared to the traditional DC pitch system, this AC pitch system completely eliminates the safety and reliability risks present in the traditional DC pitch system by replacing the pitch driver, pitch motor, and battery with an integrated AC driver 4, an AC permanent magnet synchronous motor 6, and a supercapacitor module 5, respectively. Only some usable low-voltage components, connecting cables, and limit switches are retained. This is conducive to improving the availability and power generation of wind turbine units, thereby improving the quality and efficiency of wind farms.

[0021] Understandably, the braking resistor 9 can dissipate the inertial energy generated during operation, converting the regenerated energy into heat energy; specifically, it can dissipate the energy generated by the AC permanent magnet synchronous motor 6 in generator mode, during deceleration of the AC permanent magnet synchronous motor 6, and during grid overvoltage.

[0022] In one embodiment, the integrated AC driver 4 incorporates a filter and a switching power supply to suppress electromagnetic interference, stabilize power output, and achieve efficient power conversion, thereby ensuring stable operation of the driver and the AC permanent magnet synchronous motor 6.

[0023] In one embodiment, the AC pitch system includes a first temperature sensor 7 for detecting the ambient temperature of the integrated AC drive 4 and a second temperature sensor 8 for detecting the ambient temperature of the supercapacitor module 5, the first temperature sensor 7 and the second temperature sensor 8 being electrically connected to the integrated AC drive 4.

[0024] Understandably, the first temperature sensor 7 and the second temperature sensor 8 can detect the temperature around key components such as the integrated AC drive 4 and the supercapacitor module 5, respectively, to ensure that the integrated AC drive 4 and the supercapacitor module 5 operate within the normal temperature range, thereby preventing wind turbine failure due to overheating.

[0025] In one embodiment, the AC pitch system includes three brakes, which are electrically connected to three integrated AC drives 4, and the brakes are powered by 24V; wherein the three brakes act on three AC permanent magnet synchronous motors 6 respectively.

[0026] In one embodiment, the AC pitch system includes three main limit switches and three redundant limit switches. The three main limit switches are electrically connected to three integrated AC drives 4, and the three redundant limit switches are electrically connected to the three integrated AC drives 4, respectively.

[0027] It should be noted that when the blade angle reaches 92°, the normal limit position for blade retraction, the main limit switch is triggered, which can trigger a first-level protection signal. The integrated AC driver 4 can immediately stop the AC permanent magnet synchronous motor 6 to prevent the blade from continuing to rotate. The redundant limit switch serves as the ultimate protection. When the main limit switch fails, specifically when the blade angle reaches 95°, the redundant limit switch is triggered, which can trigger a second-level protection signal. This allows the integrated AC driver 4 to use a brake or other means to forcibly stop the blade rotation.

[0028] In one embodiment, power lines and signal lines are provided between the three integrated AC drives 4 and the cabin main controller 1.

[0029] Understandably, power can be transmitted to the integrated AC drive 4 using the power line. For example, 400V AC power can be transmitted to the integrated AC drive 4, which then converts the power to drive the AC permanent magnet synchronous motor 6 and outputs power to the supercapacitor module 5 to charge it. When power is no longer supplied to the integrated AC drive 4, the supercapacitor module 5 can reverse the power supply to the integrated AC drive 8 to drive the AC permanent magnet synchronous motor 6, thus enabling the AC permanent magnet synchronous motor 6 to continue to operate normally.

[0030] It is also understandable that signal lines can be used to transmit informational electrical signals to the integrated AC driver 4, which facilitates the control of devices such as the AC permanent magnet synchronous motor 6 in the cabin.

[0031] In one embodiment, a CANopen communication line is provided between the two integrated AC drives 4 to enable communication between them via CANopen, which facilitates data synchronization, collaborative control, fault diagnosis, and system redundancy, thereby improving the reliability, control accuracy, and maintenance efficiency of the AC pitch system. A CANopen communication line is also provided between the integrated AC drives 4 and the nacelle main controller 1, and monitoring points for the main control safety chain, pitch safety chain, and main control bypass signal are added.

[0032] In one embodiment, a communication relay controller 3 is provided on the CANopen communication line between the integrated AC drive 4 and the cabin main controller 1; and / or a communication relay controller 3 is provided on the signal line between the integrated AC drive 4 and the cabin main controller 1.

[0033] Understandably, the communication relay controller 3 ensures efficient and reliable data transmission between the integrated AC drive 4 and the cabin main controller 1.

[0034] In one embodiment, an integrated AC driver 4 and an AC permanent magnet synchronous motor 6 are provided with a motor power line and a motor feedback line for feeding back temperature information inside the AC permanent magnet synchronous motor 6.

[0035] It is understandable that the integrated AC driver 4 can provide power to the AC permanent magnet synchronous motor 6 through the motor power line, and the motor feedback line can provide feedback on the temperature information inside the AC permanent magnet synchronous motor 6; accordingly, a temperature sensor needs to be installed inside the AC permanent magnet synchronous motor 6 to detect this temperature information.

[0036] It should be noted that this AC pitch system is an improvement on the traditional DC pitch system; the redundant encoder components do not need to be replaced, and the redundant design of the traditional DC pitch system is maintained; the integrated AC drive 4 can also detect the voltage and current of the AC permanent magnet synchronous motor 6 and detect the A / B encoder; in addition, a pitch safety chain can be designed to provide dual redundancy protection of software and hardware safety chains.

[0037] In the description of this utility model, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0038] While specific embodiments of the present invention have been described herein with reference to them, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. An AC pitch system, characterized in that, include: Three integrated AC drives (4) are electrically connected to the nacelle main controller (1). The integrated AC drives (4) integrate a pitch controller, a pitch driver and a capacitor charger. The integrated AC drives (4) have built-in braking resistors (9). Three sets of supercapacitor modules (5), the three supercapacitor modules (5) are electrically connected to the three integrated AC drivers (4); Three AC permanent magnet synchronous motors (6), the three AC permanent magnet synchronous motors (6) are electrically connected to three integrated AC drivers (4) respectively. Includes a first temperature sensor (7) for detecting the ambient temperature of the integrated AC drive (4), the first temperature sensor (7) being electrically connected to the integrated AC drive (4); Power lines and signal lines are provided between the three integrated AC drives (4) and the cabin main controller (1), and a CANopen communication line is provided between the two integrated AC drives (4).

2. The AC pitch system according to claim 1, characterized in that, The integrated AC driver (4) has a built-in filter and switching power supply.

3. The AC pitch system according to claim 1, characterized in that, Includes a second temperature sensor (8) for detecting the temperature around the supercapacitor module (5), the second temperature sensor (8) being electrically connected to the integrated AC driver (4).

4. The AC pitch system according to claim 1, characterized in that, It includes three brakes, each of which is electrically connected to one of the three integrated AC drives (4).

5. An AC pitch system according to claim 1, characterized in that, It includes three main limit switches and three redundant limit switches. The three main limit switches are electrically connected to the three integrated AC drivers (4), and the three redundant limit switches are electrically connected to the three integrated AC drivers (4).

6. The AC pitch system according to claim 1, characterized in that, A CANopen communication line is provided between the integrated AC drive (4) and the cabin main controller (1).

7. An AC pitch system according to claim 6, characterized in that, A communication relay controller (3) is provided on the CANopen communication line between the integrated AC driver (4) and the cabin main controller (1); and / or a communication relay controller (3) is provided on the signal line between the integrated AC driver (4) and the cabin main controller (1).

8. An AC pitch system according to claim 1, characterized in that, A motor power line and a motor feedback line for feeding back temperature information inside the AC permanent magnet synchronous motor (6) are provided between the integrated AC driver (4) and the AC permanent magnet synchronous motor (6).

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