The next generation automotive electrical power system architecture: issues and challenges

The electrical and electronic content of contemporary passenger cars and light trucks now exceeds 20% of the vehicle cost. Semiconductor content alone is growing at 16%/yr, primarily in embedded microcontrollers, safety and security systems and entertainment systems. As the automobile develops, the demand for installed capacity to support future electronic and anciliary functions is expected to exceed the historical 4%/yr. Today, the automobile electrical system consumes approximately 1.2 kW to support essential loads. With electrical ancillaries, like power assisted steering, the demand will grow to 3 kW and higher in the near term (10 to 15 years). Meeting this predicted demand in a low voltage system is one issue facing automotive electrical system design today. The challenge lies in how to meet such future demand at affordable cost and uncompromised quality. This paper summarizes candidate electrical architectures that are considered viable alternatives to today's system.