Quantitative comparison of commutation circuits for bridge inverters

The large number of published circuits for forced commutation inverters has created a selection problem for the user and designer. The cost of commutation components, with reference to rating, is often disregarded when selecting a particular circuit. The efficiency of the commutation circuit and its effect on the efficiency of the main circuit, is also often disregarded. The paper compares on a per unit basis the commutation, and powercircuit components, for five typical inverter circuits, and provides guidance on which configuration is likely to suit a particular application. While the comparison is restricted to a single-phase bridge invertor, results can frequently be extrapolated to polyphase circuits.