IEC 63409-3:2025

IEC 63409-3:2025 specifies test procedures for confirming the basic operational characteristics of power conversion equipment (PCE) for use in photovoltaic (PV) power systems with or without energy storage. The basic operational characteristics are the capability of the PCE before any limitations due to internal settings are applied to the PCE to meet specific grid support functions or specific behaviours against abnormal changes.
This document covers the testing of the following items:
a) Steady state characteristics
Test procedures to confirm operable range of PCE at steady state condition are described. The operable ranges in apparent power, active power, reactive power, power factor, grid voltage and grid frequency are confirmed according to the test procedures.
b) Transient-response characteristics
Test procedures to confirm PCE’s response against a change of operational condition are described.
This document only considers the changes within normal (continuous) operable ranges. Therefore, the behaviours against abnormal changes and grid support functions are out of the scope and are covered in other parts of this series.