Advanced DC To AC Converter

The use of electric power in aeronautical and space applications shows an increasing trend throughout the years. Equipment used for communication and navigation, control systems, pumps, actuators, precision timing devices, life support systems etc., all require electric power in some form. This creates a need for an invertor which offers: high efficiency, high power density, miniaturization, lower weight, improved EMI performance, and low acoustic noise. Higher switching frequencies for DC to AC invertor operation is an essential requirement for accomplishing the above desirable goals, but the upper limit of the switching frequency of an invertor is limited mainly by the switching losses occurring in the switching devices of the invertor. Recent developments in "soft switching converters" promises improved device utilization and substantially higher switching frequencies over their "hard switched" counterparts. In soft-switched invertors, a switch will only change state when the voltage across it and/or the current through it is zero, eliminating switching losses. As an improvement to the state-of-the-art in soft switching, the proposed converter will utilize a front end DC voltage notching circuit which will allow the DC link voltage to be brought to zero on command when an invertor switch needs to change state, thus making zero voltage switching possible. This performance advantage will be further leveraged by the use of new electronic switches (Mats) which offer substantially lower conduction losses than traditional devices. The core technology can be applied to motor control, alternate energy sources (such as fuel cells, solar cells, etc.), space power, remote sensing, uninterruptible power supplies, etc.