In this study, a new active snubber cell is proposed for pulse width modulated (PWM) converters. This snubber cell provides zero-voltage transition (ZVT) turn on and zero-voltage switching (ZVS) turn off for the main switch. In the converter with the new snubber cell, auxiliary switch is turned on with zero current switching and turned off with ZVS. Also, the main diode and all of auxiliary diodes are operating with soft switching (SS). At the same time, in this converter, all SS energy stored in the snubber inductance is transferred effectively to the output by a transformer, and so the current stress of the auxiliary switch is reduced significantly. Also, this transformer provides possibility of using the capacitors required for ZVS turning off of the main and auxiliary switches. In this converter, no semiconductor device has any additional voltage and current stresses and SS-operating conditions are maintained at very wide line and load ranges. In this study, detailed steady state analysis of the new ZVT-PWM boost converter is presented, and this theoretical analysis is verified experimentally by a 1 kW and 100 kHz prototype.

No abstract

In this paper, realization of three-phase gridconnected inverter controlled with dSPACE DS1103 control board is presented. Detailed information about power circuit, sensor board, signal isolation board and DS1103 is given in the paper. The inverter is controlled with DS1103 control board, programming the DSP via MATLAB/Simulink. Connection between the developed control algorithm in Simulink and experimental setup is made with installed DS1103 tools in Simulink. Space vector pulse width modulation technique in dq synchronous reference frame is used to control the threephase inverter. The transferred power to grid is 10 kW via three-phase inverter. The injected grid current has 3.59% THD value with 9 kHz switching frequency and 3 mH filter inductance.

No abstract