Energy consumption investigation of electromagnetic valve train at gas pressure conditions

Highlights: • Opening of EMVT has a delay of 0.2 ms per 0.1 MPa with combustion gas pressure. • Changing laws of EMVT's energy conversion is obtained with variable gas pressure. • Gas pressure causes increase of copper loss and additional differential pressure loss. -- Abstract: Electromagnetic valve train (EMVT) shows enormous potential for the improvement of IC engine thermal efficiency. The combustion gas pressure is one of challenges with EMVT applied to exhaust system, which makes serious disturbances to the opening performance and increases the energy consumption of EMVT. Therefore, coupled models between mathematical model of EMVT and engine thermodynamic model are carried out to study the effect of combustion gas pressure on EMVT. The experiments are established based on electromagnetic linear load simulator innovatively, which has fast dynamic response and high loading precision. With the electromagnetic linear load simulator, realistic combustion gas pressure conditions can be produced accurately. Simulation and experimental results show robust valve opening performance for large variations in combustion gas pressure, and the opening transition time keeps a constant of 3 ms at different gas pressure conditions, but the valve opening has a delay of 0.2 ms per 0.1 MPa. Further, we get the conclusion that gas pressure would cause an increase of EMVT's energy consumption. At the condition of 0.6 MPa gas pressure, energy consumption has an increase of 85.6%, which mainly embodies in the differential pressure loss and increase of copper loss, while the iron loss and mechanical loss remains approximately constants.