Method for designing DC/DC converters based on Zeta topology

Objectives. The work set out to develop a new design method for DC/DC converters based on the Zeta topology to calculate the ratings of inductors and capacitors of the Zeta converter with magnetically coupled inductors and verify the accuracy of the ultimate continuous mathematical model and design method based on it using SPICE simulation in the Multisim computer-aided design (CAD) system. Methods. The proposed method analyzes an ultimate continuous mathematical model to calculate the ratings of coupled inductors and capacitors of the converter. Results. The simulation of the Zeta converter with coupled inductors was carried out using the Multisim CAD system, during which the load and transfer characteristics of the converter were obtained. These characteristics show the dependencies of the currents flowing through the coupled inductors and voltages across the capacitors on the input voltage, as well as the dependence of the output voltage on the load current. The presented design method is shown to be accurate and in full agreement with the simulation results. A correlation between the transfer and load characteristics of currents and voltages obtained by simulation and calculation is established. The differences between the values calculated using the ultimate continuous mathematical model and the results of simulation in the Multisim CAD system are comparable to measurement errors. Conclusions. The proposed design method is used calculate element ratings for the Zeta topology both with and without taking the inductive coupling into account. The method can also be used to calculate the steady-state values and ripple currents of the inductors and voltages across the capacitors. The design method for DC/DC converters presented in the paper can be used for both preliminary evaluation calculations and more detailed calculations, including analysis of the device operation under various input voltages and load resistances.