High-efficiency electric motors that deliver measurable energy savings for our customers
Brief Introduction1. With the rapid development of power electronics technology and new semiconductor devices, AC speed regulation technology has been continuously improved and improved. Gradually improved frequency converters, also called VFD, are widely used in AC motors with their good output wav
1. With the rapid development of power electronics technology and new semiconductor devices, AC speed regulation technology has been continuously improved and improved. Gradually improved frequency converters, also called VFD, are widely used in AC motors with their good output waveform and excellent performance to price ratio.
For example, large electric motors and small and medium-sized roller motors used in steel mills for rolling, traction motors for railways and urban rail transit, elevator motors, lifting motors for container lifting equipment, motors for water pumps and fans, compressors, and motors for household appliances have all successively used YVF3 series VFD fan motor, and have achieved good results.
2. What are the structural differences between variable frequency motors and ordinary motors?
● Insulation level: Generally F level or higher, strengthen the strength of ground insulation and wire turn insulation, especially considering the ability of insulation to withstand impulse voltage.
● Regarding the vibration and noise issues of the motor: full consideration should be given to the rigidity of the motor components and the overall structure, and efforts should be made to increase its natural frequency to avoid resonance with various force waves.
● Cooling method: Generally, forced ventilation cooling is used, that is, the main motor cooling fan is driven by an independent motor.
● Measures to prevent shaft current: For motors with a capacity exceeding 160KW, bearing insulation measures should be adopted. Mainly, it is prone to magnetic circuit asymmetry and also generates shaft current. When the currents generated by other high-frequency components combine, the shaft current will increase significantly, leading to bearing damage. Therefore, insulation measures should generally be taken.
● For constant power variable frequency motors: When the speed exceeds 3000/min, special high-temperature resistant lubricating grease should be used to compensate for the temperature rise of the bearings.
3. For ordinary asynchronous motors, the main performance parameters to consider during redesign are overload capacity, starting performance, efficiency, and power factor. And for YVF3 series VFD fan motor, as the critical slip rate is inversely proportional to the power frequency, they can be started directly when the critical slip rate is close to 1. Therefore, overload capacity and starting performance no longer need to be considered too much.
4. For pumps and fans, the fluid flow rate is directly proportional to the first power of the speed, the torque is directly proportional to the second power of the speed, and the power is directly proportional to the third power of the speed. When the speed decreases, the power consumption of the motor decreases in a third power. Therefore, the energy-saving effect of variable frequency speed regulation is very significant.
5. YVF3 series VFD fan motor follows Chinese standard, GB755-2008 Rotating electrical machines-Rating and performance, which equals to IEC60034-1:2004.
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Standard | IEC60034 |
Voltage(V) | 220/380/400/415/440/550/660/690 |
Pole | 2/4/6/8/10 |
Speed | 3000rpm/1500rpm/1000rpm/750rpm/600rpm |
Mounting | foot-IMB3/IM1001;flange-IMB5/IM3001;face-IMB14/IM3601; vertical-IMV1/IM3011;flange-foot:IMB35/IM2001;IMV5;IMV6 |
Working duty | S1,S6,S9 |
Frame | H80~H355 |
Output range(KW) | 0.55 to 355 |
Enclosure | IP55/IP54 |
Cooling | IC416/TEFV |
Frequency(Hz) | 50/60;3～100Hz |
Application | CNC machine tools, industrial robots, various automatic mechanical equipment, flexible production lines for textile, printing, and light industry systems, steel rolling, mining, locomotive drag, aerospace, and shipbuilding,etc. |
cast iron case
The design of the cast iron case of YVF3 series VFD fan motor takes into account the heat dissipation function, which helps to remove the heat generated by the operation of the motor through appropriate heat dissipation surfaces or air cooling flowability channels, so that the motor winding operates within its rated temperature range.
vibration sensor
Vibration sensor is a single free oscillation system composed of springs, dampers, and inertial mass blocks. It converts mechanical vibrations into electrical signals that are easy to transmit, transform, process, and store through its transducer components.
terminal box
The motor terminal box is used to connect power lines and motor coils, mainly composed of a box body, terminals, screws, washers, fixing plates, and other parts.
shaft
Precision shafts are manufactured based on the tolerance of the shaft and are generally suitable for transmitting high-precision loads. The precision shaft is manufactured using high-quality materials and advanced processing technology. The tolerance control of the size and shape of the shaft is relatively strict, and it can withstand relatively large axial and radial loads.
Q: Can exhaust fans have VFDs?
A: The power of low-power exhaust fans is generally lower, usually below 100W, so using a frequency converter is not necessary. But if it is necessary to accurately adjust the speed and control the air volume of the exhaust fan, or to save electricity and extend the service life of the exhaust fan, a frequency converter can be considered. In addition, if the noise of the low-power exhaust fan is too loud during operation, the noise can also be reduced by using a frequency converter.
Q: Are VFDs bad for motors?
A: For ordinary motors, yes, there are several bad effects. For YVF3 series VFD fan motor, VFDs are not bad.
● Although we know that frequency converters can drive ordinary motors in many situations, it can cause severe heating of ordinary asynchronous motors when the output power frequency of the frequency converter is very low. Therefore, ordinary motors cannot run for a long time when the frequency is relatively low.
● We know that ordinary motors have a weakness, which is the limited ability of the silicon steel sheets of ordinary motors to convert electrical energy into magnetic energy and finally into kinetic energy, especially in the mode of frequency converter voltage frequency (U/F) control, which can easily saturate the magnetic circuit of the motor. This result is ultimately manifested in the excessive increase in motor operating temperature, which will cause the motor to rapidly heat up in the voltage frequency control mode, and over time, it will reduce the service life of the motor winding.
● The influence of high-frequency pulse waves from frequency converters on ordinary motors
We know that when the frequency converter is running, its output voltage waveform is not strictly a sine waveform. Sometimes we refer to it as sine pulse width modulation waveform (SPWM), and when outputting this waveform, higher-order harmonics will appear, and the output voltage will be much higher than the normal value. This can cause the insulation of the winding or insulation material of the ordinary motor to be broken, which is easy to cause damage to the motor.
