ZJSHUYI Influence of switching frequency on inverter output current.www....

Influence of switching frequency on inverter output current The inverter (DC/AC conversion) part of the inverter is formed by the IGBT through the sine pulse width modulation SPWM, and then through the motor winding to form a sine wave current waveform. Then the size of the switching frequency directly affects the quality of the current waveform, as well as the size of the interference, and the size of the switching frequency is more sensitive and direct. Consider adding various harmonic suppression devices, such as AC reactors, DC reactors, filters, additional sequence reactors, as well as installation wiring, grounding and other measures. This approach is more reasonable and effective, and must not be reversed. To deal with the problem, this is a very important principle. When the switching frequency is high, the current waveform is sinusoidal and smooth. In this way, the harmonics are small, the interference is small, and vice versa, when the switching frequency is too low, the effective torque of the motor decreases, the loss increases, and the temperature increases. On the contrary, when the switching frequency is too high, the loss of the inverter itself increases. , IGBT temperature rises, and the rate of change of output voltage dv/dt increases, which has a greater impact on motor insulation. www.shuyitop.com; Tel/Fax: 0086-577-62840011 WhatsApp: 008613355775769 #inverter #frequencydrive #ACvfd #frequencyinverter

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