Overview
IEC TS 63217:2021 - "Utility-interconnected photovoltaic inverters - Test procedure for over voltage ride-through measurements" - is an IEC Technical Specification that defines a standardized test procedure for Over Voltage Ride-Through (OVRT) performance of photovoltaic (PV) inverters. It focuses on inverters connected to utility grids, especially those on utility high-voltage (HV) distribution systems, but its procedures can also be applied to low-voltage (LV) single‑phase and three‑phase installations where OVRT requirements are evolving. The document also supports numerical simulation and model validation for inverter OVRT behavior.
Key topics and requirements
- OVRT scope and definitions: formal definitions such as OVRT capability, equipment under test (EUT), and grid/voltage fault terminology.
- Test circuit and equipment: recommended test circuit diagrams and required test equipment including measuring instruments, DC source, multi‑tap transformer, and grid fault simulator (including RLC-series and converter‑based emulators).
- Test protocol and procedures: structured steps covering pre-test, no-load test, load test, and acceptance tolerances; guidance on generating an OVRT curve and test points.
- Measurement accuracy and data: criteria for instrument accuracy and measurement integrity to ensure repeatable OVRT characterization.
- Assessment criteria and performance metrics: evaluation of ride‑through time, voltage swell ratio, reactive current injection, and active power during over‑voltage events (detailed in informative annexes).
- Informative annexes: methods for determining critical performance values, example OVRT curves and criteria, and test point definitions.
Applications and who uses it
- PV inverter manufacturers - to verify and design inverter OVRT functions and to document compliance for product development.
- Independent test laboratories and certification bodies - to perform standardized OVRT testing for product certification and grid‑code evidence.
- Utilities and system operators - to define acceptance testing and validate inverter behavior on HV distribution networks.
- Project developers and integrators - to assess inverter behavior in large PV plants and during site acceptance tests.
- Researchers and modelers - to validate numerical models and simulation tools against standardized OVRT measurement procedures.
Related standards
- IEC 61400-21-1:2019 (measurement & assessment of electrical characteristics)
- IEC TS 61836:2016 (PV terms, definitions, symbols)
- IEC TS 63106-1:2020 and IEC TS 63106-2:2022 (AC and DC simulators recommendations)
IEC TS 63217:2021 is a practical reference for ensuring reliable PV inverter operation during voltage swell events and for harmonizing OVRT testing across manufacturers, test labs and utilities.