company news

Question: Can the frequency inverter be used to control and adjust the speed of the single phase motor?
Answer: No. In most cases the frequency inverter cannot be used for single phase motors. Any casual use of the frequency inverter will cause damage to the equipment.
The reason is explained as below: 95% of the single phase motors found in the market are single phase capacitor split phase AC motors, which start the rotor by changing the phase difference between the winding current through the capacitance.
Diagrams: (1)(2) Single-phase capacitance operation ; (3) Single-phase two-value capacitance operation

Therefore this is big difference between the starting principles of the single phase motor and the three phase motor and another more capacitance in the motor construction will bring latent problems to the frequency inverter:
(1) The problem of high frequency resistance of capacitance. Inverter output waveform is SPWM wave. The high frequency harmonics which have a certain damage to the capacitance of several hundred Hertz, make the capacitor heated and even explode.
(2) The effect of operating capacitance on frequency conversion. With the application of the frequency inverter,the absorption and release of the power supply of the running capacitor will block the "dead zone" in waveform of the frequency inverter, resulting in the public conduction between upper bridge and lower bridge, that is, short circuit, and resulting in the burning of the power parts of the inverter.