The Analysis of Energy Transition Processes in Boost Converter

Abstract

Introduction. This article presents the analysis of energy transition processes in boost converter under the conditions of load changing. The boost converter laboratory layout is investigated with forms of the transient process caused by load changing. The transient currents and voltages are measured in harmonic and anharmonic modes. The parameters of boost converter transient modes are estimated. The analysis of energy transition processes is performed using two boost converter models. Problem statement. The boost converter circuits are used in the areas of electronics where the minimization of energy losses is strictly required. The boost converter energy losses depend on the form of transient processes caused by load changing. The purpose of energy losses minimization requires exact analysis of energy transition processes which appear under load changing. The presented work describes the responses of boost converter circuit to changing the load twice with four different transient modes. Results. The analysis of energy transition processes is performed with two models. The first model is based on the iterative mapping technique, where the currents and voltages of each period of gate driving signal are determined from the circuit parameters and initial conditions given by the previous period of driving signal. Such model allows to perform an exact analysis of current and voltage ripple transient processes. But the iterative mapping model is characterized by numerical approximation errors and requires more computation time. The second model describes the envelopes of boost converter current and voltage transient processes analytically. This model is based on the state-space averaging method which is widely used for modelling of switching circuits. Such model does not take into account the waveforms of current and voltage ripples, but it provides a more simple description of transient process envelopes which are useful for the circuit design purposes. The modeling results obtained from iterative mapping and state space averaging, match with the experimental data. Conclusions. The performed analysis shows that the energy losses depend on the transient process mode significantly. During the load transient process time, the smallest energy losses can be obtained under the critical load transient process form which is situated between periodic and aperiodic modes. Such result is obtained experimentally and confirmed by the both iterative mapping and state-space averaging models. The analytical results are confirmed by optimization procedure in MATLAB environment.