Experimental comparison of rectifiers for Lundell automotive alternators

This paper presents a comparative analysis of rectifiers by experimental approach, to improve output power and efficiency of a Lundell alternator without any geometry modification. Different topologies of rectifiers are considered using PWM or series/parallel reconfigurations of diode rectifier and simple control methods. An interleaving technique is also applied to minimize the output current high-frequency ripple generated by pulse modulation. To improve performances, this method must be associated to special multiple 3-phase winding configuration to minimize magnetic coupling. The proposed solution almost double the peak output power at 8000 rpm (from 1602 W to 3038 W) and keeps alternator losses constant.