Design and Experimental Research on Electromagnetic Shielding of Optical Transformers

In order to solve the severe issues of high noise, data loss, and even communication interruption in the electrical units of optical transformers, which operate in environments with dense high-voltage equipment and complex electromagnetic conditions, this thesis proposes a systematic electromagnetic compatibility (EMC) solution for the electrical units of optical transformers from multiple perspectives, including process, material, signal shielding, grounding technology, and filtering decoupling. The solutions encompass improving the circuit design in electronic devices, adding electromagnetic shielding covers, attaching metal foil, spraying conductive coatings, plating a layer of conductive metal, and incorporating electromagnetic wave absorbing materials around circuits and components with high electromagnetic emission capabilities within the entire electronic device casing. Additionally, grounding techniques with partial floating and mixed grounding are employed to maximize the suppression of internal noise coupling within the circuit and prevent the intrusion of external electromagnetic interference, thereby enhancing the anti-interference capability of the electrical units. Shielding technologies such as double shielding are adopted to improve the overall EMC capability of the modules and electrical units. Anti-interference transmission methods and decoupling techniques are also utilized. Experimental data demonstrates that the electrical units of the improved optical transformers meet the test requirements for EMC tests, including electrostatic discharge, conducted disturbance, and radiated disturbance. The improvement is effective, significantly enhancing the overall EMC of the product and satisfying engineering application requirements.