Which two standards are typically used for the interconnection of smart devices in a substation environment?

The correct answer is based on the critical role that both IEEE C37.1 and IEC 61850 play in ensuring interoperability and effective communication among smart devices in substations.

IEEE C37.1 is a standard that defines the performance requirements and testing methods for electrical protective relays, which are essential for the proper operation and protection of electrical power systems. It provides guidelines that help ensure devices can communicate and respond appropriately to system conditions.

IEC 61850, on the other hand, is a comprehensive standard focused on the communication networks and systems in substations. It facilitates the seamless integration of intelligent electronic devices (IEDs) and enables standardized communication protocols. This results in more efficient monitoring, control, and protection mechanisms, which are crucial for the modernized smart grid environment.

Together, these standards provide a framework for interoperability, allowing devices from different manufacturers to work together reliably within substations, which is vital for efficient grid management and safety.

The other combinations listed do not effectively encompass both the performance requirements of devices and the communication standards necessary for interoperability in a substation setting, which is why they do not match the needs prescribed in the question.