How can industrial servo drive power supplies isolate and resist interference?

Isolation of the servo drive power supply (which powers the gate driver IC) is crucial for blocking power ground noise crosstalk and improving system immunity. Etymotic's isolation solution employs either a DC-DC isolation module or transformer isolation. For the DC-DC module, decoupling capacitors should be placed on both the primary and secondary sides (10μF + 100nF on the primary side, 22μF + 100nF on the secondary side), and PWR series power inductors should be used for filtering.

In the transformer isolation solution, reinforced insulation is required between the primary and secondary windings, and a copper foil shielding layer should be wrapped around the core for grounding. To suppress common-mode noise coupling through the isolation capacitor, a Y capacitor (e.g., 1nF/Y1) can be connected across the isolation band to provide a controllable return path for high-frequency noise. Simultaneously, the transmission of the drive signal requires the use of optocouplers or digital isolators (e.g., ADuM), and their power supply side also needs to be isolated. A fully isolated drive power supply can withstand surge tests up to 5kV and EFT tests of ±4kV, ensuring stable operation in harsh power grid environments.