Reactive type : The stator of the reactive stepping motor has windings and the rotor consists of soft magnetic materials. 1.2 °、但动态性能差、效率低、发热大，可靠性难保证。 Simple structure, low cost, small step angle, up to 1.2 °, but poor dynamic performance, low efficiency, large heat generation, and difficult to guarantee reliability.
Permanent magnet : The rotor of the permanent magnet stepper motor is made of permanent magnet material, and the number of poles of the rotor is the same as that of the stator. 7.5 °或 15 °）。 Its characteristics are good dynamic performance and large output torque, but this motor has poor accuracy and large step angle (generally 7.5 ° or 15 °).
Hybrid : Hybrid stepper motors combine the advantages of reactive and permanent magnet types. The stator has multi-phase windings, the rotor uses permanent magnet materials, and the rotor and stator have multiple small teeth to improve step accuracy. Its characteristics are large output torque, good dynamic performance, small step angle, but complex structure and relatively high cost.
Divided by the windings on the stator, there are two phases, three phases and five equal series. 97% 以上的市场份额，其原因是性价比高，配上细分驱动器后效果良好。 The most popular is the two-phase hybrid stepper motor, which accounts for more than 97% of the market share. The reason is that it is cost-effective and works well with a subdivided driver. 1.8 ° / 步，配上半步驱动器后，步距角减少为 0.9 °，配上细分驱动器后其步距角可细分达 256 倍（ 0.007 ° / 微步）。 The basic step angle of this type of motor is 1.8 ° / step. After the half-step driver is used, the step angle is reduced to 0.9 °, and the step angle can be subdivided by 256 times ( 0.007 ° / micro) step). Due to friction and manufacturing accuracy, the actual control accuracy is slightly lower. The same stepper motor can be equipped with different subdivided drivers to change the accuracy and effect.
Advantages of stepper motors
、优秀的起停和反转响应； 1. Excellent start-stop and reverse response;
、电机旋转的角度正比于脉冲数； 2. The rotation angle of the motor is proportional to the number of pulses;
、由于速度正比于脉冲频率，因而有比较宽的转速范围； 3 , because the speed is proportional to the pulse frequency, there is a relatively wide range of speed;
、电机停转的时候具有最大的转矩（当绕组激磁时）； 4. The motor has the maximum torque when the motor is stopped (when the winding is excited);
、由于每步的精度在百分之三到百分之五，而且不会将一步的误差积累到下一步因而有较好的位置精度和运动的重复性； 5. Since the accuracy of each step is 3% to 5%, and it does not accumulate the error of one step to the next step, it has better position accuracy and repeatability of movement;
、电机的响应仅由数字输入脉冲确定，因而可以采用开环控制，这使得电机的结构可以比较简单而且控制成本； 6. The response of the motor is determined only by digital input pulses, so open loop control can be used, which makes the structure of the motor simpler and control costs;
、仅仅将负载直接连接到电机的转轴上也可以极低速的同步旋转； 7. Simply connect the load directly to the motor's shaft can also rotate at a very low speed;
、由于没有电刷，可靠性较高，因此电机的寿命仅仅取决于轴承的寿命。 8. Since there is no brush, the reliability is high, so the life of the motor depends only on the life of the bearing.
Disadvantages of stepper motors
、难以运转到较高的转速； 1. It is difficult to run to a high speed;
、难以获得较大的转矩； 2. It is difficult to obtain a large torque;
、如果控制不当容易产生共振； 3. Resonance is easy to occur if it is not controlled properly;
、超过负载时容易丢步，高速工作时会发出振动和噪声； 4. It is easy to lose steps when exceeding the load, and it will emit vibration and noise when working at high speed;
、在体积重量方面没有优势，能源利用率低。 5. There is no advantage in volume and weight, and energy efficiency is low.