Application of Levenberg-Marquardt Method for Optimizing Gate Driving Signals of a DC/DC Converter to Reduce Switching Resonances

In power electronic systems often serious electro-magnetic emissions are caused by the fast switching power transistors. RF oscillations may be triggered by the switching events and parasitic capacitances and inductances. In the frequency spectrum a narrowband peak can be seen. A common countermeasure is to decrease the switching slopes steepness of the gate drive signal by, e.g., inserting an additional gate resistor. This leads to decreased disturbances but also to a reduced efficiency of the system. Optimized gate control signals can improve the electromagnetic compatibility without seriously affecting the system efficiency. In this paper, a target signal-oriented gate control is applied to reduce narrow-band disturbances while maintaining fast switching slopes. The gate drive signal is optimized in the frequency domain by the Levenberg-Marquardt method. The approach is applied to a DC/DC boost converter in simulation and a laboratory setup. The benefits of the proposed method regarding to the reduction of electromagnetic disturbances and maintaining a high system efficiency are discussed.