Transport applications requiring DC/DC converters are unique in their requirement for wide input range and immunity to harsh environmental and EMI conditions making commercial or ‘standard’ industrial grade parts unlikely to be a reliable solution. This article gives an overview of the requirements in rail, automotive and industrial vehicles and introduces some off-the-shelf modular solutions which meet the specifications required.
DC/DC converters for electronic systems are found in just about all conceivable applications: consumer, IT, industrial, transport and more. Mostly they are embedded within systems, well protected from the outside world with its unpredictable power supply and environmental variations. Transport however, is different. DC/DCs are often powered directly from system batteries which can also feed other loads, generating spikes, surges and drop-outs. The transport physical environment can also be harsh with condensation, shock, vibration and rapid temperature swings between wide extremes. Also, by its nature, transport moves between different radiated EMC environments with emissions present, sometimes at high power, from other vehicles and radio, television and cellphone masts. Modular DC/DCs have become commodity parts and even the lowest cost parts can boast high performance with safety certifications. Do these match transport requirements? An examination of the standards for performance in these markets shows that special designs are generally needed.
