Inverter design output/ fan speed

[mord]

I am into inverter design, I noticed that when a fan is connected, the speed is usually low. My oscillator is an SG3525 IC, I have seen several designs using the same IC with same configuration but when a fan is connected, it rotate very fast though still buzzing, I removed the filter cap from the other design but the speed still remains, what have they done differently, I think this has to do with the peak voltage(?). Please I need answer urgently. Thanks as you help

 

[FvM]

Are you talking about an inverter (AC output) or a converter (DC output)? In the latter case, does it use a storage inductor and filter capacitor, voltage feedback?

 

[mord]

Are you talking about an inverter (AC output) or a converter (DC output)? In the latter case, does it use a storage inductor and filter capacitor, voltage feedback?

. yes, am refering to inverter (AC). There is no choke in the designs have been seeing. am still wandering about the difference

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Feedback is usually included

 

[BradtheRad]

Motors often buzz loudly when the AC supply has a waveform that is square-ish.

A sinewave causes only slight buzzing.

 

[mord]

Motors often buzz loudly when the AC supply has a waveform that is square-ish.

A sinewave causes only slight buzzing.

Yeah you right, but these inverters uses square wave oscillators, still they run fans fast only with slight buzzing