EMI/EMC in Power Electronics

Understand the fundamental concepts of electromagnetic interference (EMI) and electromagnetic compatibility (EMC) in power electronics.

Definition and importance of EMI and EMC in power electronic systems. Regulatory standards and compliance requirements (e.g., CISPR, FCC, IEC). Overview of electromagnetic fields, wave propagation, and coupling mechanisms (conducted and radiated interference). Impact of EMI on system performance, reliability, and safety.

Identify sources and types of EMI in power electronic systems.

Common sources of EMI: high-speed switching devices (e.g., MOSFETs, IGBTs), transformers, inductors, and capacitors. Types of EMI: differential mode, common mode, radiated, and conducted interference. Influence of circuit layout, switching frequency, and component selection on EMI generation. Case studies of EMI issues in power supplies, inverters, motor drives, and other power electronic systems.

Learn techniques for measuring and analysing EMI/EMC issues.

Overview of EMI measurement equipment: spectrum analysers, EMI receivers, LISNs (Line Impedance Stabilization Networks). Measurement setups: conducted emissions, radiated emissions, and immunity testing. Use of time-domain and frequency-domain analysis for identifying EMI sources. Compliance testing: pre-compliance and full compliance testing procedures.

Explore design strategies to mitigate EMI and ensure EMC in power electronics.

Circuit design techniques: minimizing loop areas, optimizing trace routing, and proper component placement. Switching techniques: soft-switching, spread spectrum modulation, and snubber circuits. PCB layout best practices: ground planes, decoupling capacitors, and via placement. Use of simulation tools for predicting and mitigating EMI/EMC issues.

Understand the role of filtering, shielding, and grounding in EMI/EMC control.

Filtering: design and application of EMI filters (LC filters, common-mode chokes, ferrite beads). Shielding: materials and techniques for shielding against radiated EMI (Faraday cages, conductive coatings). Grounding: single-point grounding vs. multi-point grounding, ground loops, and their impact on EMI/EMC. Integration of filtering, shielding, and grounding strategies in product design.

Implement and troubleshoot EMI/EMC solutions in practical power electronic applications.

Practical considerations for implementing EMI/EMC solutions in real-world systems. Troubleshooting common EMI/EMC issues: identifying sources, refining design, and retesting. Case studies: successful EMI/EMC design in automotive, aerospace, industrial, and consumer electronics applications. Continuous improvement strategies: iterative design, testing, and optimization for EMC compliance.