The current of 12 V automobile powernet is too large too improve the alternator's power to meet with the increasing requirement of the automobile electrical equipment. The promising 42 V higher electrical system voltage will be required to meet these ever increasing loads and will help to improve the power delivery efficiency. This paper provides the projections of some approaches that could be employed are compared to provide the electrical power to meet the electrical load. In addition, a key component to produce 42 V electricity-a three phase automobile alternator with combined stator is provided. It is a brushless alternator thus the reliability, limited lifetime and low field current of the brush is avoid. To output steady 42 V power, the three-phase regulator is designed. The generator and regulator experiment is carried out on test platform. And the results demonstrate the effectiveness of the generator and regulator.