Nowadays, frequency conversion speed control technology has become the main speed control program, which can be widely used in various industries for stepless variable speed drive. As the frequency converter is more and more widely used in the field of industrial control, it makes the use of frequency converter motors more and more widespread as well
A motor, also called an electric motor, is an electric device that converts electrical energy into power energy. When the current flows in a magnetic field, the motor that operates by receiving power for rotary motion is relatively common, but there exist many types of motors, if the motor can be roughly divided into two types, AC and DC, according to the type of drive power used, and these motors can be further divided into subtypes.
Compared with ordinary motors, inverter motors and ordinary motors in appearance is not different places, however, in terms of function or use and so on there are different places. However, many customers do not know which type of motor to choose when making purchases. Below we will take inverter motors and ordinary motors as an example and briefly introduce their differences.
Inverter motor and ordinary motor is what
Inverter motor is also called frequency conversion motor, through the frequency converter we often say, in order to control the motor. In fact, in addition to the inverter motor itself, such as three-phase asynchronous motors, by adding a frequency converter can also realize the function of an inverter motor. It is characterized by the frequency can be adjusted according to the load to change the speed, such as lower voltage, you can use inverter motors to reduce the frequency, so that the motor to get a reliable start; such as lighter loads, you can use inverter motors to reduce the frequency to achieve the purpose of lowering the current and speed, so as to save energy. Ordinary motors, also called motors, is a kind of electric device used to convert electrical energy into power energy, used in various electrical appliances or machinery, such as industrial robots, motors are the driving device of industrial robots, which can provide motion for the arm of industrial robots. Its characteristic is as long as the power is on, it can be rotated, as long as the power off it will stop rotating, and its rotation and stopping will not immediately be able to respond to, and it can not be adjusted speed, its speed can only be slowed down through the reducer.
Frequency conversion motor and ordinary motors have their own advantages, such as frequency conversion motor in the start at the same time to achieve the effect of frequency conversion, can be applied to a wider range of operating frequencies, therefore, its advantages have been recognized by the public, but also the market share of the higher proportion of products, but increased the electromagnetic load, so that the magnetic circuit is not easy to saturate; and the structure of ordinary motors is simple and easy to maintain, the price is also more than the frequency converter motors affordable, but will be used because of overheating, and it will be used for overheating. But the use will be burned because of overheating.
Frequency conversion motor and ordinary motor what is the difference
1, the heat dissipation conditions are different: ordinary motors and cooling fans use the same line, while inverter motors and cooling fans with the line is separate. Therefore, when the frequency of the ordinary motor is too low, it may be burned due to high temperature. Ordinary motors are designed in accordance with the frequency of the utility power and the corresponding power, and can only run under rated conditions, while inverter motors need to overcome the high temperature and vibration at low frequency, so inverter motors are better than ordinary motors in design.
2, insulation level is different: inverter motor is required to withstand high-frequency electromagnetic fields, so its insulation level is higher than ordinary motors. Under normal circumstances, ordinary motors can not be applied to frequency converter, but in the actual operation process, in order to save costs, in the case of the need for speed regulation, will use ordinary motors instead of frequency converter motors, but ordinary motor speed accuracy is not too high, usually used in fans and pumps in energy-saving transformation.
3, the service life is different: the service life of the frequency conversion motor is usually longer than the ordinary motor. Ordinary motor in operation, the carrier frequency can reach several thousand to more than ten kilohertz, stator windings will be subjected to higher voltages, as if it exerts a steeper shock voltage, which will make the ordinary motor turn-to-turn insulation needs to withstand a more brutal experience. The inverter motor can work under the voltage of the rectifier filter circuit, its performance will be more stable, and longer service life. Inverter motor is a kind of frequency converter to control the motor, and ordinary motors in the heat dissipation conditions, insulation level and service life and so on some not the same.
In some old equipment remodeling, in order to achieve certain results, the frequency converter is used to drive the motor. In order to save investment, three-phase asynchronous motors should be utilized as much as possible.
Under what circumstances is it recommended to use special inverter motors?
① working frequency > 50HZ or even up to 200 ~ 400HZ, generally ordinary three-phase asynchronous motor mechanical strength and bearings can not cope.
② operating frequency <10HZ, the load is large and to work continuously for a long time, ordinary three-phase asynchronous motors rely on the machine's airfoils can not meet the cooling needs of the motor, the motor will be seriously overheated, especially easy to damage the motor.
③ motor and drag the load speed ratio D ≥ 10 and frequent changes in the work of the bar (D = Nmax / Nmin).
④ The speed regulation ratio D is large, the working cycle is short, the moment of inertia GD2 is also large, the forward and reverse rotation runs alternately, and it is required to realize the working mode of energy feedback braking.
⑤ If it is more suitable to use inverter motor due to the need of transmission, use inverter motor.
Inverter motor has the following characteristics.
①Tail motor heat dissipation, which is driven by an independent constant-speed micro-motor, the air volume of the radiator is constant, independent of the speed of the inverter motor.
② The mechanical strength of the inverter motor design ensures that the motor can be used at the highest speed and is safe and reliable for a long time.
③ The dynamic frequency range of the magnetic circuit design is large, that is, it can adapt to the requirements of the highest use frequency and the lowest use frequency.
④ The designed insulation structure is much higher than the common three-phase asynchronous motor, which is more capable of withstanding high temperature and higher impact voltage.
⑤ When running at high speed, the noise, vibration and loss generated are not higher than those of ordinary three-phase asynchronous motors of the same specification model.