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Littelfuse designs Class J fuses with indication feature, which receives Plant Engineering's "Product of the Year" award Littelfuse acquires Teccor Electronics for their industry- leading SIDACtor devices and power thyristors Nissan introduces the LEAF, a battery electric vehicle (BEV) Littelfuse builds global sensor technology platform with acquisition of ACCEL AB; Hamlin, Inc.; and Sigmar S.r.l Littelfuse acquires a select portfolio of semiconductor products from ON Semiconductor Littelfuse acquires Semitron Industries, expanding into gas discharge tube, TVS diode, and protection thyristor technologies Tesla unveils the Roadster, the company's first vehicle Tesla begins mass production of the Model S, a premium BEV Littelfuse invests in Monolith Semiconductor, Inc., a start-up developing silicon carbide (SiC) technology Tesla introduces the Model 3 for the mass market. Littelfuse acquires Monolith Semiconductor, Inc. and IXYS Corporation
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Safety
The two biggest safety threats in an EV charging station are electrical shock and overcurrent. Electrical shock is usually the result of a ground fault.
Electrical Shock A ground fault is an unintended contact between an energized conductor and ground or the equipment frame. Insulation breakdown is the typical culprit. Dust and moisture can also cause unintended pathways for electricity. Wet and dusty environments, such as those found around outdoor equipment, require diligence in design. Overcurrent By their nature, vehicle charging stations are connected to a power supply that has high available fault current. Electrical faults, including those that start ground faults, can draw high current that can be very destructive, damaging components, twisting busbars, starting fires, even causing an arc-flash incident-a kind of explosion that could injure or kill anyone standing nearby.
Efficiency
Power semiconductor devices convert AC power into the DC power needed to recharge vehicle batteries. To match the level of charge to what the vehicle battery needs, the power semiconductor device controls the charge through switching, a process that naturally incurs power losses in the form of heat. In an EV charging application, heat can create engineering challenges. SiC MOSFET devices are now available that blend high operating voltages and fast switching speeds, a combination typically not available with traditional power transistors. To be useful in automotive charging applications, they must operate at high junction temperatures and feature low gate resistance, low gate charge, low output capacitance, and ultra-low on-resistance. Designers prefer devices that offer high power density and reduce the size and weight of filter components, which reduces cost and space requirements.
Reliability
Unlike consumer devices like laptops that are engineered for a lifetime of three to five years, DC charging stations are expensive, so buyers need them to last for 10 years or more in order to get a return on their investment. Proper circuit protection will keep that investment working reliably for a longer.
Semiconductor devices are sensitive to electrical threats and must be protected from overcurrent by fuses.
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