Yanwen Lai

Yanwen Lai

Senior EMC design engineer at Lucid Motors

Research Experience

University of Florida     Supervisor: Prof. Shuo Wang

  1) Develop conducted EMI noise models for a three-phase inverter.

  2) Characterize parasitic impedance, extract stray capacitance and near electromagnetic field distribution and predict CM/DM noise in full-wave simulation.

  1) Investigate the magnetic emissions from inductors of various winding structures, test inductors’ susceptibility under external interference.

  2) Develop the magnetic near-field emission model based on reluctance circuit theory for the inductors, and evaluate the induced noise voltages due to external interference for various inductor winding structures.

  3) Propose a winding structure for the coupled CM inductor with improved high-frequency performance, reduction of magnetic near field emissions, and immunity to external magnetic fields, optimize the inductor winding structure based on the proposed analysis to reduce magnetic near field emissions and in-circuit conducted EMI.

  4) Develop a general inductor high-frequency model with parasitics, propose winding capacitance cancellation techniques based on network theory, increase inductor high-frequency impedance and improve high-frequency performance.

  5) Practice small-signal tests to verify the proposed inductor winding cancellation techniques, build EMI filters with the proposed inductor and measure conducted EMI using LISNs and a spectrum analyzer to validate the proposed model.

  1) Investigate the electric radiated emissions for DC/DC non-isolated converters for EV applications

  2) Extract PCB trace parasitics and component parasitics and develop a complete circuit simulation model to predict conducted EMI for DC/DC non-isolated converters.

  3) Investigate the EM characteristics of the SMD metal alloy inductor, investigate the cavity resonance of the anechoic chamber, acquire the EM characteristics of the absorption materials, build a full-wave 3D simulation model to predict electric radiated emissions.

  4) Investigation of the monopole antenna’s mechanism in measurement and mismatch between the prediction and the measurement due to the test setup.

  1) Propose and design a 3.3kV SiC MOSFET grid-connect double-sided cooling power module with various novel EMI suppression techniques.

  2) Develop EMI noise models for the 3.3kV SiC MOSFET grid-connect double-sided cooling power module, build conducted and radiated emissions test benches and conduct measurements.

  3) Propose various EMI suppression techniques for the power module, such as integrated capacitors and resistors, partial shielding layer pattern, guarded ring, busbar filter and quadrupole layout design.

  4) Well-tune and optimize the proposed EMI suppression techniques, use Ansys 3D simulation and experiment to validate the proposed techniques.

  1) Investigate the conducted EMI models for on-board chargers of electric vehicles.

  2) Characterize EMI filter performance by S-parameters and extract CM transfer gain, build test fixtures to apply mixed-mode technique based on network theory, extract trace parasitic using 3D model of evaluation board for WBG device characterization.

  3) Develop in-house test benches, conduct module level CE EMI tests for inverters, vehicle level CE and RE tests for EVs based on CISPR 25, teamwork with cross-group members to troubleshoot excessive EMI issues.