Optimal cam design and system control for an electromechanical engine valve drive

An electromechanical valve drive system using a cam-based mechanical transformer has been proposed to achieve variable valve timing in internal combustion engines. This technique promises substantial improvements in fuel economy and emissions. However, there are several challenges to transform this concept into an attractive commercial product, especially achieving acceptable power consumption and actuator size. In this paper, significant reduction in power consumption, torque requirement, and transition time are achieved. These improvements are based on an effective nonlinear system model, optimized design of the cam - a key system component - and exploration of different control strategies to maximize performance.