IEC 62116:2014

Overview

IEC 62116:2014 sets out a standardized test procedure for evaluating the effectiveness of islanding prevention measures in utility-interconnected photovoltaic (PV) inverters. Developed by the International Electrotechnical Commission (IEC), this globally recognized standard provides minimum requirements to ensure that anti-islanding methods in utility-interactive PV inverters - both single-phase and multi-phase - are tested and verified for performance and repeatability. Islanding prevention is critical for grid safety and reliability, making this standard essential for PV inverter manufacturers, test laboratories, certifying bodies, and grid operators.

Key Topics

• Islanding in PV Systems: Islanding is an abnormal situation in grid-tied PV installations where, after being disconnected from the main grid, a local segment containing both load and generation continues to operate. This can present hazards including equipment damage and safety risks to utility workers.
• Anti-Islanding Techniques: The standard addresses both detection and prevention strategies embedded in PV inverters, ensuring that these devices stop energizing the grid under islanded conditions.
• Test Procedures: IEC 62116:2014 specifies test circuits, measurement methods, and criteria for determining the run-on time-the period during which the inverter continues to operate after disconnection.
• Testing Equipment:
  • Measurement instruments (e.g., digital oscilloscopes, data acquisition systems)
  • DC power sources such as PV array simulators
  • AC power sources and configurable AC loads (resistors, inductors, and capacitors)
• Pass/Fail Criteria: Minimum requirements for run-on time and inverter response are established, helping to classify equipment as 'non-islanding' under defined conditions.

Applications

IEC 62116:2014 is primarily used in the following contexts:

• PV Inverter Manufacturers: Ensures that products comply with international grid safety requirements before market launch.
• Testing & Certification Laboratories: Provides a reproducible methodology for assessing anti-islanding functionality and for providing compliance certificates.
• Grid Operators and Utilities: Offers a reference for accepting PV systems onto the grid, minimizing the risk of unintentional islanding events and their associated hazards.
• Regulatory Authorities: Underpins policy, utility codes, and national safety requirements for grid-connected distributed generation.
• Other Distributed Energy Resources: While focused on PV systems, the methodology is applicable-with technical review-to other inverter-based resources like fuel cells or microturbines.

Related Standards

Adopting IEC 62116:2014 is typically coordinated with other PV and grid interconnection standards, such as:

• IEC 61727: Photovoltaic (PV) systems - Characteristics of the utility interface
• IEC/TS 61836: Solar photovoltaic energy systems – Terms, definitions and symbols
• Local utility grid codes: National and utility-specific voltage and frequency trip requirements
• Other IEC standards: Covering power quality, safety, and performance of inverters and distributed generation systems

Practical Value

Implementing IEC 62116:2014 delivers:

• Enhanced Grid Safety: Reduces the risk of hazardous islanding situations, protecting both utility personnel and equipment.
• Global Market Access: Demonstrates conformity with internationally recognized grid interconnection standards required in many markets.
• Repeatable, Verifiable Results: Enables consistent testing and clear, auditable performance records for compliance.
• Interoperability: Supports the smooth integration of PV systems with utility grids, aligning with evolving smart grid and distributed energy trends.

IEC 62116:2014 ensures PV systems uphold fundamental grid safety and reliability-an essential requirement as solar energy penetration increases worldwide.