Automotive electrical systems circa 2005

Demands for better fuel economy and more electric power are driving cars to multiple higher voltages. In the next 10 years the electrical systems in some luxury automobiles will be so changed as to be almost unrecognizable. Although they will doubtless employ the old reliable 12 V lead-acid battery, their loads will be driven by a variety of voltages, both AC and DC, perhaps derived from a single AC distribution network. Designers will be able to match voltages to individual loads for best efficiency and performance-lights perhaps at 6 V AC, electronics at 5 V DC, active suspension at 350 V DC, and motors and actuators at 42 V DC. The digital signals controlling those loads will be carried by a separate communications network. The enabling technology for these advances are semiconductors. The authors discuss the future development of automobile electrical systems.