# Reasons why power transformers cannot be converted

Reasons why power transformers cannot be converted

Power Transformers can be transformed, and the improved voltage is more suitable for production and life. Many people may want to know whether the power transformer can be converted, that is, the frequency of voltage transformation. The answer is no, let's take a look at it. The reason why you can't change the frequency.

The transformer is manufactured based on the principle of electromagnetic induction. The core of electromagnetic induction is the change in the flux of the closed loop to generate voltage. The magnetic flux is transmitted in a closed core, so the rate of change is uniform, that is, the frequencies on both sides are consistent. However, since the number of turns on the two sides is different, the voltage changes, that is, the transformer is realized.

The construction of the frequency converter is generally to first convert the alternating current into a direct current through a non-controllable rectifier circuit, and then convert the voltage through the switch of the power electronic device. Therefore, the inverter is a kind of switching power supply, but the output voltage waveform is not a standard sine wave, but a PWM wave, but the corresponding current waveform is close to a sine wave. SVPWM technology is currently used for the control of power electronic devices. Of course, the inverter will also be transformed during frequency conversion, in order to keep the magnetic flux of the motor constant. The typical change is that when the frequency is lower than 50HZ, the voltage is reduced, and constant torque control is adopted; when the frequency is higher than 50HZ, the voltage is the rated voltage of the motor, and does not rise accordingly, and constant power control is adopted.

By understanding the transformer and the frequency converter, it is found that their construction is completely different. The transformer is a closed iron core, and the rate of change is the same, which cannot achieve the purpose of frequency conversion.