The thesis addresses printed circuit board parasitics extraction with the Ansys Q3D Extractor® software tool and their integration into electrical simulations to examine their influence on the power transistor switching sequence. The presence of parasitics causes overvoltages on the transistor, oscillations, and electromagnetic emissions. Based on Maxwell’s equations the Q3D Extractor® numerically computes the RLGC parameters of the structure.
The extraction is based on a prototype circuit board comprising a single branch of the electric motor drive inverter. The Q3D Extractor® extracts the parasitics in the form of a SPICE equivalent subcircuit model. Then we connect the components of the functional circuit to the model and run the simulations of the obtained circuit. Using an external microcontroller development board we implement the system for testing the power transistor switching sequence while driving an inductive load by the double pulse method. The simulation and measurement results match well.
In the Matlab® program, the simulation of the electromagnetic conducted emissions is performed to observe the level of emissions caused by the parasitic effects.
|
