How should the power frequency magnetic field immunity of a PCS (Power Storage System) be designed?

The PCS's immunity design against power frequency magnetic fields (such as IEC 61000-4-8) primarily targets environments with strong power frequency magnetic fields (such as near high-current buses or transformers), preventing the magnetic field from inducing interference voltages or currents in the internal loops of the equipment. Design measures include:

1. Reducing the area of sensitive loops: This is the most effective method. Optimize the PCB layout to minimize the loop area of critical low-frequency analog circuits (such as current sampling and voltage references).

2. Magnetic shielding: For particularly sensitive components or the entire control board, use high-permeability materials (such as permalloy) to create shields, guiding the magnetic field around sensitive areas.

3. Using differential signals: For easily affected low-frequency signal transmissions (such as PT/CT sampling), use twisted-pair cables or differential inputs, utilizing common-mode rejection ratio to cancel induced common-mode interference.

4. Filtering: Use a low-pass filter to filter out induced power frequency and harmonic components before the signal enters the ADC or operational amplifier.

5. Keeping away from interference sources: When arranging the control board within the cabinet, keep it as far away as possible from high-current conductors.