| Abstract |
The paper proposes a new method to measure the High Frequency (HF) current components in electronic converters and defines a model able to address the converter operation on a wide frequency range (100 kHz ÷ 30 MHz). Main features of the proposed approach are that the developed model is calculated by a suitable automatic procedure that performs the measurements during the normal operations of the converter, instead of using HF circuital sub-models of the power devices, only related to the parasitic inner parameters, connection wires, and diodes, and therefore regardless the modulation technique. In this way, the HF admittance of the converter has been calculated taking to account the instantaneous switches configuration and, therefore on the basis of the switching PWM strategy. According to the proposed approach, the proposed dynamic HF model of the power converter is composed by several black boxes, each related to a single converter status or to a groups of states with the same response. Each box acts differently to a HF voltage excitation, according to the number of devices that are contemporary on and off, while the converter is modulated. By knowing the PWM modulation strategy, the sequence of the states is unambiguous and therefore the model of the converter is entirely definite. Simulations and experimental results are presented in order to evaluate the consistence of the proposed approach. |
