电机的选型方法（Motor Selection Method）

最佳选择需要考虑到电源、控制、运转条件等因素来选择单相串励电机、有刷电机或是无刷电机。如果希望由敝公司代为选择的话，请确认好下述各项条件。                                                                                 

Power supply, control option, operational environment, etc are factors need to be considered when select the optimal motor solution, including universal motor, dc brushed motor and dc brushless motor. The following information need to be provided if clients require our company to suggest motor solution.

• 电源的条件：使用电压范围、整流电源或者电池、电流限制有无。                                                                                             
  Power Supply：Range of voltage, rectified power supply or battery, any limitation of current flow.

• 是否需要编码器、减速箱、刹车等配件？                                                                                                                                                     
  Do you need encoder, gearbox, brake and other accessories？

• 运转情况：连续、间歇、正逆、驱动时间、加锁、短路制动。                                                                                                       
  Operation Condition: Continuous, intermittent, clockwise or counter clockwise, working time, locking and short-circuit braking.
  

• 环境状态：温度、湿度等。                                                                                                                                                                           
  The state of the environment ：The State of Environment.   

• 包括齿轮箱、编码器、刹车在内的尺寸限制。                                                                                                                                           

  Size limits including gearbox, encoder, and brake.

直流电机技术参数说明 ( DC Motor technical parameter description )

1、技术用语 ( Technical words )



2、空载电流 ( No load current )

电机在额定电压下，空载达到稳定状态时所消耗的电流，此参数受温度影响。

The current consumed after stable under the rated voltage when there is no loaded. This parameter will be affected by different temperatures.

3、空载转速 ( No load speed )
电机在额定电压下，空载达到稳定状态时获得的最高转速。                                                                                                           
The highest speed obtained after stable under the rated voltage.

4、堵转力矩 ( Stall torque )
电机在额定电压下，转速为零时输出的力矩。                                                                                                                                   
Stall Torque is the torque produced by the motor whose output rotation speed is zero under the rated voltage.

5、起动电流 ( Stall current )
在额定电压下，起动时和加锁时流过的最大电流。                                                                                                                           
Stall current is the current that the motor draws when its shaft if prevented from moving.

6、最大输出功率 ( Maximum output power )--Pmax
电机在额定电压下，能输出的最大机械功率。                                                                                                                               
The maximum output power of the motor at the rated voltage.

7、最大输出效率 ( Maximum output efficiency )--ηmax

电机输出的机械功率与消耗的电功率的最高比率。                                                                                                                             
The maximum ratio of output power of the motor to the consumption of electrical power.

8、电动势常数 ( Back - EMF constant )----KE ( mV/rpm )
此常数反映了转子的感应电压和旋转速度之间的关系。                                                                                                                   
The constant corresponding to the relationship between the induced voltage in the rotor and the speed of rotation.

9、转矩常数 ( Torque constant )--Kt ( g.cm/A )
此常数反映了电机产生的转矩和电流消耗之间的关系。                                                                                                                             
 The constant corresponding to the relationship between the torque developed by the motor and the current drawn.

10、速度常数 ( Speed constant )--Kn ( rpm/V )
当电机负载恒定时，加在电机上每伏电压引起的速度变化。                                                                                                                       
The speed variation per volt applied to the motor terminals at the constant load.

11、机械时间常数 ( Mechanical time constant )--tm （ms）
电机从静止状态加速到最终空载转速的63%所需要的时间。                                                                                                                         
The time required for the motor to reach a speed of 63% of its final no load speed, from standstil.

国际单位换算表( Internationalunit conversion table )

电机温升 ( Motor temperature rises )

电机通流后产生电流热效应，随着时间的推移，电机表面的温度不断地上升直至稳定。稳定的条件是在3个小时内前后温差不超过2℃，此时 测得电机表面的温度为此电机的最终温度，温度的单位为度（℃）。上升的温度中超过周围空气的温度（环境温度）的这一部分温度称为温升，温 升的单位为开氏（K）。温升就是电机温度比周围环境温度高出的数值。                                                                                                    

The motor will heat up when it is powered on. The temperature of the motor's surface will continue to rise until it is stable. Within 3 hours after the temperature is stable, the temperature is allowed to change within 2 degrees Celsius.The part at which temperature rises above the ambient air temperature (ambient temperature) is called the temperature rises. The unit of temperature rises is kelvin (K). The temperature rise is the value that higher than the ambient temperature.          

额定温升：是指在设计规定的环境温度(十40℃)下，电动机绕组的最高允许温升，它取决于绕组的绝缘等级。                      

Rated temperature rises: refers to when the environmental temperature is under , the maximum allowable temperature rise of the motor winding. It depends on the winding insulation grade.

计算公式( Calculation formula )： θ=T2-T1
θ——温升( Temperature rises )                                                                                                                               
T1——实际冷却状态下的绕组温度 ( 即环境温度,室温不允许超过40℃ )                                                                       
Winding temperature in actual cooling condition ( that is ambient temperature, room temperature not exceeding 40℃ )                                                                                                                                                     
T2——发热状态下绕组温度 ( Winding temperature in heating condition )


绝缘等级 ( Insulation class )

电动机的绝缘等级是指其所用绝缘材料的耐热等级，分A、E、B、F、H、C、N、R级，一般电机绝缘等级多采用B、F、H级。

Insulation class of motor refers to the heating resistance class of insulation material including A, E, B, F, H, C, N, R. Insulation class of motor is using B, F, H mostly.

If you have any questions about the above information, please feel free to send an email to BG motor's sales engineer at info@china-bgmotor.com； BG motor's professional sales engineers will provide you with professional help and services, and will recommend and customize motors suitable for your equipment according to your specific requirements.