The Difference Between Variable Frequency Power and Frequency Converter

The whole circuit of the variable frequency power is composed of AC - DC - AC - filter and other parts, so its output voltage and current, waveform are pure sine wave, very close to the ideal AC power supply. It can output grid voltage and frequency of any country in the world. The frequency converter is composed of AC - DC - AC (modulated wave) and other circuits, and the standard name of the frequency converter should be frequency conversion governor. The waveform of the output voltage is a pulse square wave, and the harmonic components are many, the voltage and frequency change proportionally at the same time, can not be adjusted separately, does not meet the requirements of AC power supply, in principle can not be used as a power supply, generally only for the speed regulation of three-phase asynchronous motors.

Point of Distinction:

1. The frequency converter generally does not contain an output filter circuit and outputs PWM pulse width waves.

2. The output voltage of the frequency converter is approximately proportional to the frequency.

3. The output frequency of the frequency converter is arbitrarily variable.

4. The variable frequency power generally outputs a fixed frequency, such as 50HZ, 60hz, 400HZ, etc.

5. The output voltage of the variable frequency power is a constant value, such as 380V, 660v and so on.

6. The variable frequency power contains a filter loop, and the output is a standard sine wave.

7. The output voltage of the variable frequency power is closed-loop control, which is basically not affected by the voltage fluctuation of the power supply (Generally, the voltage needs to be raised first, and then the dynamic voltage regulation).

8. The special variable frequency power also has some other characteristics.