A regular motor can be used directly after having a frequency converter installed. If a regular motor can work with a frequency converter, then why use special frequency-converter driven motors?
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Our factory’s ordinary motors can be used directly after installing frequency converters. If ordinary motors can work with frequency converters, then why use special frequency-driven motors? Although frequency-driven motors are a bit more expensive, for our company’s energy-saving initiatives, it seems that installing frequency converters directly is a better option. Someone has applied it – could you help analyze why a regular motor can be used after installing an inverter? I posted a thread before, and some people said that regular motors cannot be used with inverters
This post was last edited by wang*nhua77020 on 2017-11-1 20:29. Variable-frequency motors can have their speed adjusted arbitrarily within their speed control range without causing any damage to the motor. Ordinary motors can also have their speed reduced or increased, but the range of such adjustments is limited; especially at low speeds, as this can cause the motor to overheat or even get damaged. In ordinary fans, the cooling fan and the fan motor share the same wire, whereas in variable-frequency fans, these two components are separated. Therefore, when the frequency conversion of a regular fan is set too low, it may burn out due to overheating. Therefore, ordinary motors cannot be driven using frequency converters. However, in practice, to save costs, ordinary motors are used in place of frequency-driven motors in many applications where speed control is required. The speed control accuracy of ordinary motors is not high, and this approach is often adopted in energy-saving upgrades of fans and water pumps. Although we do this frequently, it does not necessarily mean that ordinary motors can replace frequency-driven motors.
Poor heat dissipation. Different insulating paints result in different steel-silicon wafers.
Since variable-frequency motors have to withstand high-frequency magnetic fields, their insulation rating must be higher than that of ordinary motors. These motors feature enhanced slot insulation; this is achieved either by using stronger insulation materials or by increasing the thickness of the slot insulation, in order to improve their ability to withstand high-frequency voltages. The operating point of a conventional motor is generally at the magnetic saturation point; when used for frequency conversion, it tends to saturate, resulting in high excitation currents. In contrast, variable-frequency motors are designed with an increased electromagnetic load, which prevents the magnetic circuit from saturating easily.