good performance cheap high efficient ac induction motor

7.Why stepper motor torque will vary with the increase of rotational speed down? When stepping motor rotation,the motor of each phase winding inductance will form a reverse electromotive force;The higher the frequency,reverse electric The greater the potential.Under the function of it,the motor with frequency (or speed) and the phase current decreases,which leads to torque decline.8.Why can generator rotor and stator operate properly when stepping motor at low speed,but above a certain speed won't be able to start,accompanied by whistler? Step motor has a technical parameters: no-load start frequency,namely step by step Motor under no-load condition can normal boot pulse frequency,if the pulse frequency is higher than the value,the motor does not start properly,may be lost or blocked.In a load Under the condition,Start frequency should be lower.If you want to make the motor to achieve high-speed rotation,the pulse frequency should be to accelerate the process,the start frequency rate is low,and then in a certain high frequency acceleration to want (electricity Machine speed from low speed to high speed).9.How to overcome the two-phase hybrid stepping motor vibration and noise during low speed? 

Stepper motor rotates at low speed vibration and noise is its inherent shortcomings,can adopt the following solutions to commonly Overcome: a.if the stepper motor work on resonant zone,but by changing the reduction ratio and other mechanical transmission to avoid the resonance region;B.using with the function of subdivision drive,this is the most commonly used,The easiest way;C.to step away from the Angle brake rotor of smaller stepper motor,such as three-phase or five phase stepper motor;D.for ac servo motor,can almost completely overcome the vibration and noise,but become This is higher;E.add magnetic damper on the motor shaft,on the market for this product,but the mechanical structure change is bigger.10.The fine fraction of subdivision driver can represent accuracy? Stepping motor subdivision technology is essentially an electronic damping technology (please refer to the relevant literature),its main purpose is to reduce or eliminate the weak Eliminate the low-frequency vibration of the stepping motor,improve the operation precision of the machine is only a supplementary function of subdivision technology.

Such as in the step Angle is 1.8 ° two-phase hybrid stepping motor,if fine Points drives the fine fraction of set to 4,then the motor running resolution for each pulse 0.45 °,the precision of the machine can achieve or close to 0.45 °,still depends on the subdivision driver segmentation Other factors such as current control accuracy.Different manufacturers of subdivision drive accuracy

may vary widely;The more difficult it is to fine grade,the greater the precision control.11.With four

phase hybrid stepping motor drives the series connection and and what is the difference between the

connecting method? Generally consists of two phase four phase hybrid stepping motor driver to

drive,therefore,the connection can be used Series connection or parallel connection to connect two

phase using four phase motor.In series connection in place of motor speed electricalmotor1.blogspot.com is used commonly,the need to drive the output current for the motor phase current of 0.7 Times,thus motor heating small;And connection generally use in motor speed higher occasions (also called high speed connection),needed to drive the output current for the motor phase current of 1.4 times,and electricity Fever is relatively large.