What are the differences between PCS laboratory testing and field EMC for energy storage systems?

The EMC test results of PCS in a standard laboratory may differ significantly from its EMC performance in an actual installation site. The main reasons include:

1. Different grounding conditions: Laboratories have ideal low-impedance grounding, while on-site grounding impedance may be higher and unbalanced, affecting common-mode noise discharge and immunity.

2. Load and power grid conditions: Laboratories use clean power supplies and loads, while on-site power grids have high harmonics, complex impedances, and diverse loads, potentially exciting different resonances and noises.

3. Installation and cabling: Laboratory cables have fixed lengths and routing specifications, while on-site cabling may be longer and more messy, and shielding and grounding processes may be inadequate, becoming major factors in radiation and coupling.

4. Environmental noise: Electromagnetic noise from other equipment exists on-site, creating complex background interference.

5. Multiple units in parallel: Multiple PCS units operating in parallel on-site may interact and generate new EMC problems. Therefore, the design needs to consider more stringent on-site conditions and conduct on-site verification.