12 POWER MODULES https://www.vicorpower.com/ Issue 4 2025 Power Electronics Europe www.power-mag.com Power modules simplify creepage and clearance design solutions for electric vehicles Why overmolding is the key to solving arcing issues in 48V automotive power systems Arcing is not a new problem for electrical engineers, but if overlooked it can have next five years. Emerging as a front runner for this new architecture, the higher voltage of an 800V battery demands greatly increased creepage and clearance distancing, generating challenges in the size and spacing of electrical systems. Higher voltage power drives increases in component spacing necessary to prevent electric breakdowns (arcing). Vehicle life expectancy is about two decades with proper creepage and clearance design, but much shorter if arcing is not properly accounted for in the design phase. Arcing can cause electric components to degrade over time possibly creating safety issues. OEMs now face two key issues related to creepage and clearance requirements that must be addressed. 1: New creepage and clearance considerations for 48V 2: Greater risk caused by 48V architecture compared to the legacy 12V architectures What should design engineers be aware of for proper creepage and clearance in a 48V PDN? Creepage and clearance requirements are extremely important safety measures that Figure 1 Conversion to a 48V bus reduces the vehicle’s total current draw from over 250A to under 75A without impacting the electrical content of the vehicle. Since 1908, the current demand in automobiles has grown exponentially with the addition of vehicle electronics. In the 1960s OEMs increased voltage from 6V to 12V, causing current to drop for the first time in 60 years. Today, most OEMs still use the 12V bus but are rapidly converting to 48V out of necessity to accommodate an influx of high-power electronics. Figure 2 Creepage and clearance requirements are international safety measures to mitigate the risk of arcing. These requirements must be met to ensure safety and functionality. Lack of proper distancing may result in excess heat, directly damaging or compromising the power delivery network. Higher voltage requires up to 60% greater space in between components. This additional spacing can consume substantially more board space, enlarging the entire power system design which is problematic for most systems with a pre-defined footprint. tragic consequences. Earlier this year a cargo ship carrying automobiles from China to Mexico caught fire, sparked by what observers believe to be a malfunction within the vehicles’ electrical system, raising concerns around safety standards regarding EVs. The industry has relied on 12V power systems to supply power to their vehicles since the 1950s; however, as technology advances, so must the industry. With automakers requiring more power for EVs and PHEV models, the transition to 48V power systems and high-voltage batteries is inevitable. However, this move requires deep consideration concerning creepage and clearance safety requirements. In addition to upgrading the 48V bus, OEMs are moving to higher voltage batteries and further complicating creepage and clearance specifications. According to Market Report Analytics (MRA), the projected compound annual growth rate for 800V batteries will exceed 30% in the
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