THD Increase in SVPWM Controlled Inverter When Switching Frequency Raised from 5kHz to 10kHz

Hi,

Im studying about the SVPWM control of inverter for reactive power compensation. When I increased the switching frequency 2 to 5 kHZ the THD of current harmonics is reduced. But when I increased the switching frequency 5 to 10 kHz THD of current harmonics is increased according to 5 kHz values. How can we explain this situation?

It is known that when frequency is increased the THD values are reduce. But this is opposite.

Hi Mustafa.

THD-Frequency concept varies with the kind of loads you have. There are two types of loads, the linear and nonlinear loads. Linear loads are loads that changes its impedance when there is an applied voltage and the nonlinear loads are just the opposite of linear loads.

The good example of it is when power up a system with high current but low voltage. The system will heat up easily because of the excessive current flow which also produce THD. Currents does not deliver power to a system, it is the voltage.

check some detailed information on IEEE 519

Good Luck ^^