PWM technology influences the characteristics of motor

Stator And Rotor ac induction motor parts 

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1. 20 years manufacturing experience 
2. competitive price,high quality 

3. Material: silicon steel
After the last illustrates the chopper battery and motor current is no longer the same physical process, the following mathematical expression is used to demonstrate the PWM influences the characteristics of motor. Motor PWM control theory is a familiar formula (power tube as an ideal switch device, it does not auto spare parts cause obvious errors), namely 3 phase induction motor the VD = rho VB (1), DVD - the average voltage of the motor VB - battery voltage. As long as the filter capacitance is large enough, the battery internal resistance is small enough, VB can be considered to be stable. Rho - control pulse duty ratio (0 ≦ rho ≦ 1). Chopper state rho for a decimal. (1) show that there are chopping, voltage of the rotor motor is reduced, this is the principle of speed regulation. Chopper is stable after, motor current waveform is cyclical approximate triangular wave, can be mathematically proved that the motor current average ID (if for the brushless motor, ID should be interpreted as the average of the conduction phase within the current). ID = IB/rho or IB = rho ID (2) that the average - IB battery current in motor current be amplified to the battery current IB 1 / rho times. With the current of battery, transform the big current of motor or motor torque, this is one of the important role of the controller, so, sometimes referred to as the converter controller. 


Y2 series high power China ac motor

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1. effiency: IE2 and IE1 
2. 20 years manufacturing experience 
3. 12 months guarantee 

4. low noise and vibtration 
At this time, acmotor2.blogspot.com the motor of the electric potential equation for VD R0 = ED + ID * (3) in R0 - motor diesel generator set coil resistance ED - the counter electromotive force. ED is proportional to motor speed locked-rotor when ED is 0, if the current limit of the controller is stable chopper technology, magnetic generator the above various remains valid. Type of motor can be obtained by (3) locked-rotor current IDmax, reuse (1) get IDmax = VD/R0 = rho t VB/R0 = rho tIB0max (4), IB0max = VB/R0 -- without stalling a motor current controller, also single phase induction motor called full pressure starting current rho t - design decision control pulse duty ratio. This shows that the maximum current of a motor is unlimited flow of rho t times, be reduced, which is exactly what we expect of current limit. Using (2) and (4), can be obtained after the battery generator current stable value (not the maximum reasons shall be described below), the motor current and full pressure maximum starting current relation between IBfinal = IDmax alternator generator rho t = 2 t IB0max rho (5) ac induction motor of these three values are measurable, the above relationship can also be verified. When rho = 1, the equivalent of the motor directly connected to the battery, so (4) into a VB R0 = EB0 + IB0 * (6) (3) and (6), respectively, described the motor is chopping and no chopping the potential equilibrium equation of state of the two. (6) of the motor current and back emf with index 0, with the state of the chopper motor current and back emf value is not the same.