Why can not the frequency converter be used as a variable frequency power supply?
The entire circuit of the variable frequency power supply is composed of AC-DC-AC-filter and so on. Therefore, the output voltage and current waveform are pure sine wave, which is very close to the ideal AC power supply. Can output any grid voltage and frequency of any country in the world. The inverter is composed of alternating current and an alternating current (modulation wave) and other circuits, the inverter standard called the frequency converter. The output voltage of the waveform for the pulse square wave, and harmonic components, voltage and frequency at the same time in proportion to change, can not be adjusted separately, does not meet the requirements of AC power. In principle, can not do the use of power supply, generally only for three-phase asynchronous motor speed.