阅读说明：本技术 星型两级式自主谐振协同限速系统及设有该系统的风机 (Star two-stage type autonomous resonance cooperative speed limiting system and fan with same ) 是由 张赞 殷志锋 吕存杰 秦涛 吴鑫鑫 马军磊 栗伟周 申鑫 臧佳宁 马超洋 于 2021-01-08 设计创作，主要内容包括：本发明涉及一种星型两级式自主谐振协同限速系统及设有该系统的风机,星型两级式自主谐振协同限速系统包括转子结构、定子结构和RLC谐振电路；所述定子结构包括星形连接的三相定子绕组；所述转子结构包括永磁转子,永磁转子用于与风机同轴设置；所述RLC谐振电路的结构包括三个星形连接的谐振电容器和三个星形连接的谐振电感,各谐振电容器和谐振电感分别连接定子结构中相应的绕组,并在连接的线路上分别设置有相应的谐振电阻。本发明所提供的技术方案中,由于限速系统能够防止风机的转速过大,所以风机不会工作在极限工况下,从而提高风机的安全性和使用寿命,并且能够减少对制动摩擦片的损耗,降低风机制动系统的成本。(The invention relates to a star two-stage type autonomous resonance cooperative speed limiting system and a fan with the same, wherein the star two-stage type autonomous resonance cooperative speed limiting system comprises a rotor structure, a stator structure and an RLC (radio link control) resonant circuit; the stator structure comprises three-phase stator windings in star connection; the rotor structure comprises a permanent magnet rotor, and the permanent magnet rotor is coaxially arranged with the fan; the structure of the RLC resonant circuit comprises three star-connected resonant capacitors and three star-connected resonant inductors, wherein each resonant capacitor and each resonant inductor are respectively connected with corresponding windings in the stator structure, and corresponding resonant resistors are respectively arranged on the connected circuits. In the technical scheme provided by the invention, the speed limiting system can prevent the fan from rotating at an overlarge speed, so that the fan cannot work under a limit working condition, the safety and the service life of the fan are improved, the loss of a brake friction plate can be reduced, and the cost of a fan braking system is reduced.)

1. The star-shaped two-stage autonomous resonance cooperative speed limiting system is characterized by comprising a rotor structure, a stator structure and an RLC resonance circuit; the stator structure comprises three-phase stator windings in star connection; the rotor structure comprises a permanent magnet rotor, and the permanent magnet rotor is coaxially arranged with the fan; the structure of the RLC resonant circuit comprises three star-connected resonant capacitors and three star-connected resonant inductors, each resonant capacitor and each resonant inductor are respectively connected with a corresponding winding in the stator structure, and corresponding resonant resistors are respectively arranged on the connected circuits;

the star-shaped two-stage autonomous resonance cooperative speed limiting system is used for:

the output braking torque increases along with the increase of the rotating speed of the fan; and outputting the maximum braking torque when the rotating speed of the fan reaches the protection rotating speed.

2. The self-resonating two-stage speed-limiting motor according to claim 1, wherein the rotor structure further comprises a synchronous reluctance rotor.

3. The fan provided with the star two-stage autonomous resonance cooperative speed limiting system comprises a fan body and is characterized by further comprising the star two-stage autonomous resonance cooperative speed limiting system;

the star-shaped two-stage autonomous resonance cooperative speed limiting system comprises a rotor structure, a stator structure and an RLC resonance circuit; the stator structure comprises three-phase stator windings in star connection; the rotor structure comprises a permanent magnet rotor, and the permanent magnet rotor and the fan body are coaxially arranged; the structure of the RLC resonant circuit comprises three star-connected resonant capacitors and three star-connected resonant inductors, each resonant capacitor and each resonant inductor are respectively connected with a corresponding winding in the stator structure, and corresponding resonant resistors are respectively arranged on the connected circuits;

the star-shaped two-stage autonomous resonance cooperative speed limiting system is used for:

the output braking torque increases along with the increase of the rotating speed of the fan; and outputting the maximum braking torque when the rotating speed of the fan reaches the protection rotating speed.

4. The wind turbine provided with the star-shaped two-stage autonomous resonant cooperative speed limiting system according to claim 3, wherein the rotor structure further comprises a synchronous reluctance rotor.

Technical Field

The invention relates to the technical field of fan brake control, in particular to a star-shaped two-stage type autonomous resonance cooperative speed limiting system and a fan with the same.

Background

With the decrease of traditional fossil energy such as coal, petroleum and the like and the increasing problem of generated environmental pollution, the research and utilization of renewable energy are more and more emphasized in all countries in the world, and wind power generation gradually becomes one of the important ways for energy utilization in all countries in the world due to the advantages of low price, cleanness, environmental protection and abundant resources. Due to the pressure of environmental pollution, the countries in Europe and America have been vigorously developing wind power generation, and the installed capacity of wind power generation is increasing day by day.

The biggest difficult problem faced by wind driven generators is the reliability problem, namely the speed limit protection problem in case of strong wind. According to the regulations of safety agencies in the wind power plant standards Association: for a wind turbine not less than 1kW, the safety mechanism can limit the maximum working speed of the wind wheel not to exceed 125% of the rated speed; for a wind turbine with the power less than 1kW, the safety mechanism can limit the maximum working speed of the wind wheel to not exceed 150% of the rated speed. The brake of the fan is a mechanical device for braking the wind driven generator, and the types of the common brakes include a block brake, a disc brake and the like. The German HSW-250T wind turbine adopts two mechanical disc brake systems of rotor brake and safety brake, and the two brakes are hydraulic caliper disc brakes. The domestic brake hydraulic system has the effect of 'soft braking' by adding the damping tube, so that the brake can achieve 'flexible' contact (larger impact force is avoided), but the reaction time of the hydraulic cylinder is prolonged, and the thrust of a brake pad on the basis of the reduction of hydraulic pressure is gradually increased. The scholars in China have proposed that the braking performance is improved by improving the structure of the braking system, an automatic anti-lock braking system is applied to the braking system of the wind driven generator, and the braking system is respectively arranged on a high-speed shaft and a low-speed shaft and is realized by combining certain control measures. In addition, the fan can be caused to execute safe shutdown under the condition of power failure of a power grid by changing a brake program, but the system needs to be additionally provided with a UPS system to temporarily supply power to a control system after the power failure of the power grid so as to realize the purpose.

The fan brake system should apply a larger braking force to meet the requirement of rapid braking, however, when the fan rotates at a high speed, considerable vibration and an overlarge dynamic load peak may be caused in the system to be braked, which may damage the system, cause larger material fatigue and aging, further increase the operation and maintenance cost, for example, an electromagnetic disc type friction brake matched with a certain 50KW medium-sized wind driven generator at present, the wear resistance of a friction plate is insufficient, and the friction plate may be seriously worn in less than three years, so that the brake regulation failure is easily caused, and the safe operation of the wind driven generator set is seriously affected. In addition, the disc type friction brake not only is easy to cause sudden locking and impact a power grid, but also is easy to splash sparks to cause fire.

Disclosure of Invention

The invention aims to provide a star-shaped two-stage type autonomous resonance cooperative speed limiting system and a fan with the same, and aims to solve the problems of high cost and poor safety of a fan braking system in the prior art.

In order to achieve the purpose, the invention adopts the following technical scheme:

the star-shaped two-stage autonomous resonance cooperative speed limiting system comprises a rotor structure, a stator structure and an RLC resonance circuit; the stator structure comprises three-phase stator windings in star connection; the rotor structure comprises a permanent magnet rotor, and the permanent magnet rotor is coaxially arranged with the fan; the structure of the RLC resonant circuit comprises three star-connected resonant capacitors and three star-connected resonant inductors, each resonant capacitor and each resonant inductor are respectively connected with a corresponding winding in the stator structure, and corresponding resonant resistors are respectively arranged on the connected circuits;

the star-shaped two-stage autonomous resonance cooperative speed limiting system is used for:

the output braking torque increases along with the increase of the rotating speed of the fan; and outputting the maximum braking torque when the rotating speed of the fan reaches the protection rotating speed.

Further, the rotor structure further comprises a synchronous reluctance rotor.

The fan provided with the star two-stage autonomous resonance cooperative speed limiting system comprises a fan body and the star two-stage autonomous resonance cooperative speed limiting system;

the star-shaped two-stage autonomous resonance cooperative speed limiting system comprises a rotor structure, a stator structure and an RLC resonance circuit; the stator structure comprises three-phase stator windings in star connection; the rotor structure comprises a permanent magnet rotor, and the permanent magnet rotor and the fan body are coaxially arranged; the structure of the RLC resonant circuit comprises three star-connected resonant capacitors and three star-connected resonant inductors, each resonant capacitor and each resonant inductor are respectively connected with a corresponding winding in the stator structure, and corresponding resonant resistors are respectively arranged on the connected circuits;

the star-shaped two-stage autonomous resonance cooperative speed limiting system is used for:

the output braking torque increases along with the increase of the rotating speed of the fan; and outputting the maximum braking torque when the rotating speed of the fan reaches the protection rotating speed.

Further, the rotor structure further comprises a synchronous reluctance rotor or an asynchronous reluctance rotor.

The invention has the beneficial effects that:

according to the technical scheme provided by the invention, the star-shaped two-stage autonomous resonance cooperative speed limiting system is arranged in the fan, autonomous intervention can be carried out when the rotating speed of the fan exceeds a limited speed, the braking torque is increased instantaneously, and further speed limiting protection of the fan is realized. In the technical scheme provided by the invention, the speed limiting system can prevent the fan from rotating at an overlarge speed, so that the fan cannot fly due to the overlarge rotating speed of the fan, such as galloping and the like, the loss of the fan can be reduced, and the safety of the fan is improved; meanwhile, the brake friction plate does not need to be braked when the rotating speed of the fan is too high, so that the loss of the brake friction plate can be reduced, the frequency of replacing the brake friction plate is reduced, and the use cost of the fan is reduced.

Drawings

Fig. 1 is a schematic structural diagram of a star-shaped two-stage autonomous resonance cooperative speed limiting system in an embodiment of a wind turbine.

Detailed Description

The embodiment of the fan is as follows:

the embodiment provides a fan with a star two-stage autonomous resonance cooperative speed limiting system, which structurally comprises a fan body and the star two-stage autonomous resonance cooperative speed limiting system, wherein the structure of the star two-stage autonomous resonance cooperative speed limiting system is shown in fig. 1 and comprises a rotor structure, a stator structure and an RLC (radio link control) resonant circuit.

The rotor structure comprises a permanent magnet rotor, the permanent magnet rotor and the fan body are coaxially arranged, and the permanent magnet rotor is driven to rotate when the fan body rotates.

The stator structure comprises A, B, C three-phase windings which are connected in a star shape; when the permanent magnet rotor rotates, an alternating magnetic field is generated, and a three-phase winding of the stator structure generates induced potential.

The RLC resonant circuit includes three star-connected resonant inductors LA, LB, LC, and three star-connected resonant capacitors CA, CB, CC, and three-phase resonant resistors RA, RB, and RC.

And each resonance inductor and each resonance capacitor are respectively connected with a three-phase winding in the stator structure, and the three-phase resonance resistor is respectively connected on a line connecting each phase resonance capacitor and the resonance inductor with the corresponding phase winding.

In the running process of the fan body, the permanent magnet rotor and the synchronous reluctance rotor coaxially rotate along with the fan body, the stator winding is connected with the resistor and the capacitor load in series, and the rotating speed of the fan body determines whether the star-shaped two-stage type autonomous resonance cooperative speed limiting system enters an RLC resonance state or not. The coordination has two levels, namely, the coordination is in the function coordination between two rotors in a star two-stage autonomous resonance coordination speed limiting system and between the star two-stage autonomous resonance coordination speed limiting system and an RLC resonance circuit.

The fan that is equipped with star two-stage formula autonomous resonance speed limit system in coordination that this embodiment provided, its theory of operation is:

the fan body rotates to drive the permanent magnet rotor to rotate, an alternating magnetic field is generated, and a three-phase winding of the stator structure generates induced potential;

when the rotating speed of the fan body is lower than the protection rotating speed, namely when the difference value between the rotating speed of the fan and the protection rotating speed is not smaller than a first set value, the amplitude and the frequency of the induced potential of the stator winding are smaller, the RLC resonance circuit is in a non-resonance state, the braking torque of the star two-stage type autonomous resonance cooperative speed limiting system is close to zero, namely the star two-stage type autonomous resonance cooperative speed limiting system does not output the braking torque;

when the rotating speed of the fan body is increased, the induced potential amplitude and the frequency of the three-phase winding of the stator structure are increased;

when the rotating speed of the fan body is close to the protection rotating speed, namely the difference between the rotating speed of the fan body and the protection rotating speed is smaller than a second set value, the induced potential frequency is close to the resonance frequency of the RLC resonance circuit, the induced current of the stator winding is greatly increased, the braking torque output by the star-type two-stage autonomous resonance cooperative speed limiting system is correspondingly and rapidly increased, the induced potential frequency of the stator winding reaches the resonance frequency of the RLC resonance current, and the braking torque output by the star-type two-stage autonomous resonance cooperative speed limiting system reaches the peak value, so that the rotating speed of the fan is limited, and the rotating speed of the fan is prevented from being. In the process, the star-type two-stage autonomous resonance cooperative speed limiting system can autonomously perform active intervention limitation on the rotating speed of the fan without manual intervention.

The protection speed is determined by the parameters of a resonant capacitor, a resonant inductance and a resonant resistance in the RLC resonant circuit.

As other implementation modes, the rotor structure further comprises a synchronous reluctance rotor, the synchronous reluctance rotor is arranged coaxially with the fan body, when the three-phase winding of the rotor structure generates induced potential, an alternating magnetic field is also generated, and the synchronous reluctance rotor rotates in the alternating magnetic field in an induced mode to limit the speed of the fan.

The embodiment of the system is as follows:

the present embodiment provides a star two-stage autonomous resonant cooperative speed limiting system, which has the same structure as the star two-stage autonomous resonant cooperative speed limiting system in the above fan embodiment, and the system is described in detail in the above fan embodiment, and will not be described here.

The embodiments of the present invention disclosed above are intended merely to help clarify the technical solutions of the present invention, and it is not intended to describe all the details of the invention nor to limit the invention to the specific embodiments described. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the corresponding technical solutions.