PWM technology influences the characteristics of motor

Stator And Rotor ac induction motor parts 

Specifications
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

Specifications
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.

Current transformer, transformer principle

 generator Stator Rotor 
Specifications
1. 20 years manufacturing experience 
2. competitive price,high quality 
3. Accessories Series: stator and rotor
Large and small current in the power supply electric circuit voltage difference from several to tens of thousands of AnDouYou Ann. For convenience of secondary instrument measuring need into a more uniform current, in addition line voltage is high, such as direct measurement is very dangerous. Current transformer is current 3 phase ac induction motor transformer and electrical isolation effect. Earlier, most of display instrument is a pointer type current meter, so the current transformer secondary level most of the electric current is the ampere (e.g., 5 a, etc.). Now wholesalemotor.blogspot.com most of the power measurement, digital and computer sampling signal is commonly milliamperes (0 to 5 v, 4-20 ma, etc.). Micro ct (current transformer) secondary current as milliamperes, between the main transformer and sampling. Micro current transformer has also been called "instrument use current transformer". (the instrument with a current transformer with a layer of meaning is using more current than Induction motor the precision of the current transformer in the laboratory, is generally used electric motor in expanding instrument range.)

What is the switch 2

 AC fan cooling motor fan cover 
Specifications
1. Customised
2. good quality
3. Surface treatment: Galvanize
4. Type: Motor Cover 
Until 1938, invented the crossbar (cross bar) switches to solve the above problems, relative to the step by step system switches, important improvements it has two aspects: 1. The use of the contact pressure relay control connection array instead of the big action step by step, thus reducing the wear and noise, improve the reliability and the connection speed; 2. The transition from direct control to indirect control method, so that users dial pulse is not directly control switch action, and the first received by register, electric fan motor storage, and then through the marker drive connector, indirect continue to complete the users. This way of indirect control separate control part way with words, to increase the control efficiency, flexibility and picked up speed. 


Totally Enclosed Protect Feature and Three-phase Phase low rpm ac electric motor

Specifications
power range: 0.12-18.5 kW 
Centre height of frame: 63-160 mm 
Rated Voltage: 380 V 

Rated Frequency: 50Hz or 60Hz 
Because the crossbar switch has a series of advantages, so it occupies an important position in the development of the telephone exchange, has been widely used, until now, quite a number of magnet generator countries in the world and the public telephone network is still in the minority areas of China and use the switches With the birth of the semiconductor devices and computer technology and the rapid development of violently hitting the traditional electromechanical exchange structure, make it to the electronic. Bell companies in the United States after the hard work in 1965, produced the world's first commercial stored Three phase motor program control electronic switch (No. 1 ESS), which marks the telephone switches from the mechanical age into electronic age, making exchange technology in the era of change. Because the electronic switch has small volume, quick speed, easy to provide efficient and reliable service, etc, caused great interest from all over the world. In the process of development have developed various types of electronic switches.