ABB KUC755AE106 3BHB005243R0106 励磁单元

ABB  KUC755AE106 3BHB005243R0106 励磁单元

ABB  KUC755AE106 3BHB005243R0106 励磁单元是一种宽调速电机，它结合了永磁同步电机和电励磁同步电机的优点，又克服了它们各自的缺点。因此，它在宽速度运行范围的风力发电系统和电驱动系统具有广阔的应用前景。 混合励磁同步电机的基本由于混合励磁电机在结构上实现了电机气隙磁场的直接调节与控制，突破了传统永磁电机通过电枢电流矢量控制实现弱磁或增磁的局限，结构上可有多种实现方式。 按照转子（动子）的运动方向可分为旋转式混合励磁电机和直线式混合励磁电机；从电机永磁体放置位置可分为转子永磁型混合励磁电机和定子永磁型混合励磁电机。

ABB  KUC755AE106 3BHB005243R0106 励磁单元是一种综合了永磁体和励磁线圈的电机，其结构和原理如下： 结构 混合励磁电机主要由定子和转子两部分组成。定子由电机的外壳、定子绕组、励磁线圈和传感器等部分组成。转子由永磁体和绕组组成，其中永磁体通常采用高能磁体材料，绕组则连接电枢和励磁线圈。 工作原理 混合励磁电机通过控制励磁电流和电枢电流的大小和方向，从而实现电机的转速和转矩控制。 在正常运行时，混合励磁电机的励磁线圈会被外部直流电源激励，产生磁场，同时电枢电流也会经过电枢绕组，并产生旋转磁场，进而与励磁磁场相互作用，从而实现电机转动。 在低速和高扭矩的情况下，通过增加励磁磁场的强度可以增加电机的输出扭矩。而在高速和低扭矩的情况下，通过降低励磁磁场的强度可以降低电机的转矩。 混合励磁电机的优点在于可以实现高扭矩、高效率和高精度控制，同时由于采用了永磁体和励磁线圈的结合，可以实现更加灵活的控制方式。缺点是电机结构相对复杂，成本较高，同时需要对励磁线圈进行精密控制，因此对控制器的要求较高。 

类型 混合励磁电机主要有两种类型：永磁励磁型和电磁励磁型。其中，永磁励磁型混合励磁电机采用永磁体和励磁线圈的组合结构，较为常见；而电磁励磁型混合励磁电机则采用电磁体和励磁线圈的组合结构，优点是可以通过改变励磁电流实现控制。 应用 混合励磁电机广泛应用于各种需要高扭矩、高精度控制和高效率的场合，例如：自动驾驶汽车、机器人、航空航天、医疗设备、电动工具等。同时，混合励磁电机也可以通过调整励磁电流和电枢电流的控制方式，实现高速运行和大功率输出，因此也适用于电动汽车、电动船舶等领域。

 发电机励磁回路中的灭磁电阻起什么作用 发电机励磁回路中的灭磁电阻主要作用有两点：一是防止转子绕组间的过电压，使其不超过允许值，二是将磁场的能量变为热能，加速灭磁过程。 转子绕组的过电压是因为转子电流突然断开，磁场发生突变引起的，当用整流器励磁的同步发电机出现故障，在过渡过程中励磁电流变负时，由于整流器不能使励磁电流反向流动，励磁回路像开路一样，从而导致绕组产生可达额定电压10倍以上的过电压。 将磁场的能量变为热能是因为在灭磁开关断开后，会将灭磁电阻自动并接在发电机转子绕组两端构成一个通路，使转子磁场中储存的能量通过灭磁电阻时消耗在其上，因此也就加速灭磁过程。

ABB  KUC755AE106 3BHB005243R0106 励磁单元

ABB KUC755AE106 3BHB005243R0106 excitation unit is a wide speed regulation motor, which combines the advantages of permanent magnet synchronous motor and electric excitation synchronous motor, but also overcome their respective shortcomings. Therefore, it has broad application prospects in wind power generation system and electric drive system with wide speed operating range. The basic of hybrid excitation synchronous motor Because the hybrid excitation motor realizes the direct adjustment and control of the motor air gap magnetic field in the structure, breaking through the traditional permanent magnet motor through the armature current vector control to achieve weak or increased magnetic limitations, the structure can be realized in a variety of ways. According to the movement direction of the rotor, it can be divided into rotary hybrid excitation motor and linear hybrid excitation motor. From the position of permanent magnet, the motor can be divided into rotor permanent magnet mixed excitation motor and stator permanent magnet mixed excitation motor.

ABB KUC755AE106 3BHB005243R0106 excitation unit is a combination of permanent magnet and excitation coil motor, its structure and principle are as follows: Structure hybrid excitation motor is mainly composed of stator and rotor two parts. The stator consists of the shell of the motor, the stator winding, the excitation coil and the sensor. The rotor consists of a permanent magnet, usually a high-energy magnet material, and a winding that connects the armature and the exciting coil. By controlling the size and direction of the excitation current and armature current, the speed and torque of the motor can be controlled. In normal operation, the excitation coil of the hybrid excitation motor will be excited by the external DC power supply to generate a magnetic field, while the armature current will also pass through the armature winding and generate a rotating magnetic field, and then interact with the excitation magnetic field to achieve motor rotation. In the case of low speed and high torque, the output torque of the motor can be increased by increasing the strength of the exciting field. In the case of high speed and low torque, the torque of the motor can be reduced by reducing the strength of the exciting magnetic field. The advantages of hybrid excitation motors are that they can achieve high torque, high efficiency and high precision control, and at the same time, thanks to the combination of permanent magnets and excitation coils, more flexible control can be achieved. The disadvantage is that the motor structure is relatively complex, the cost is high, and the excitation coil needs to be precisely controlled, so the controller has higher requirements.

There are two main types of hybrid excitation motors: permanent magnet and electromagnetic excitation. Among them, permanent magnet hybrid excitation motor adopts the combination structure of permanent magnet and excitation coil, which is more common. The electromagnetic hybrid excitation motor uses the combination structure of electromagnetic and excitation coil, which can be controlled by changing the excitation current. Hybrid excitation motors are widely used in a variety of applications requiring high torque, high-precision control and high efficiency, such as: autonomous vehicles, robotics, aerospace, medical equipment, power tools, etc. At the same time, the hybrid excitation motor can also achieve high-speed operation and high-power output by adjusting the control mode of the excitation current and armature current, so it is also suitable for electric vehicles, electric ships and other fields.

The main role of the magnetic resistance in the generator excitation circuit is two points: one is to prevent the overvoltage between the rotor windings, so that it does not exceed the allowable value, and the other is to change the energy of the magnetic field into heat energy to accelerate the magnetic process. The overvoltage of the rotor winding is caused by the sudden disconnection of the rotor current and the sudden change of the magnetic field. When the synchronous generator excited by the rectifier fails, the excitation current becomes negative during the transition process, because the rectifier can not make the excitation current flow in reverse, the excitation loop is like an open circuit, resulting in the overvoltage of the winding up to 10 times the rated voltage. The energy of the magnetic field is changed into heat because after the magnetic switch is turned off, the magnetic resistance is automatically connected to both ends of the generator rotor winding to form a path, so that the energy stored in the rotor magnetic field is consumed on the magnetic resistance when it passes through the magnetic resistance, so that the magnetic field is accelerated.

ABB  KUC755AE106 3BHB005243R0106 励磁单元