Research on rectification strategy optimization for linear internal combustion power generation systems based on active short circuit control

Abstract This study investigates the characteristics of significant amplitude-frequency variations and periodic phase sequence changes in the output electrical energy of linear internal combustion power generation systems. It conducts an analysis of the power generation characteristics of linear motors during stable operation and investigates rectification control strategies for three-phase electrical energy. Traditional control strategies involve the combination of three-phase uncontrolled rectification and chopper circuits. However, the three-phase uncontrolled rectifier bridge can lead to severe current discontinuity in the phase current of the linear motor, affecting the stability of the power generation system. This study proposes a Boost-type controllable rectifier based on the active short-circuit of the upper bridge arm of ASC, employing a composite control strategy of PWM-PFM. Simulation results indicate that the output bus voltage under ASC control can be stably controlled, with a higher voltage peak compared to uncontrolled rectification, and without causing a current discontinuity in the motor-side phase current. This approach is capable of adapting to loads of varying voltage levels and offers superior control performance.