# Smart Grid Protection, Automation and Control: Challenges and Opportunities
## 3 Evolution of Substation Architectures and Digital Modernizations for Smart Substations
### Virtualization of Protection, Automation and Control (VPAC)
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**Infracstructure** & **Description** \\ \hline Safety & Real-time protection: Meet stringent real-time data \\ and & processing requirements. \\ Reliability & High availability: Ensures continuous availability of critical \\  & applications, even during hardware or software failures. \\ \hline Communication & Virtual and physical networks: The deployment of network \\ Network & virtualization technologies facilitates the interconnection of \\  & virtualized applications with the underlying physical \\  & network infrastructure. \\  & IEC 61850 standard: It defines communication via Ethernet, \\  & thereby facilitating data exchange and control between \\  & substation devices. \\ \hline Deployment & Flexible and rapid deployment: The implementation of new \\  & applications and updates is conducted flexibly, thereby reducing \\  & the time and costs associated with maintenance. \\  & Maintenance & Testing and validation: Comprehensive laboratory testing and \\  & field validation are conducted to guarantee compliance with \\  & operational requirements before deployment. \\ \hline \hline \end{tabular}
\end{table} 
Table 8: _Cont._  
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Application-level performance requirements: These represent one of the most critical features of VPAC systems. Following IEC 61850-5, these are based on the real demands of the P&C applications themselves, and thus must be the same for traditional relay-based systems and virtualized platforms. This consistency ensures that VPAC systems will not escape the duty to live up to the same high standards as traditional P&C systems, providing reliable and timely protection and control [53]. Performance Indicators: The performance evaluation of VPAC systems will include several key metrics that guarantee operation systems are reliable [54]. One of the key metrics involves response time, which refers to the speed at which protection mechanisms can detect a fault and take remedial measures. It includes the round-trip time, tracking the complete fault-handling process, starting from fault injection, and progressing through MU signal conversion to SMV, the communication latency, VPAC preprocessing, the execution of protection algorithms, and GOOSE message transmission to trigger tripping at the MU. In fact, internally required benchmarks for the VPAC systems are very high. For example, pre-processing cycles need to be under 200 \(\upmu\)s, and configuration cycles should be completed within 1000 \(\upmu\)s. Virtual switches--be they by KVM or VMW--can play their role in defining overall performance, and might result in higher latencies after all. A proper system design is required to counteract additional latencies. Another important metric is that of data throughput, ensuring that the VPAC system will be able to support high volumes of data from sensors, relays, and merging units without degradation, hence allowing for real-time control and monitoring. It is also very important to have high reliability in this context; that is, the system should not be interrupted for at least a little while in order to maintain the safety and stability of electrical grids. These metrics demonstrate the need for fine engineering and system validation, because any delay in processing or the failure of any communication used can compromise the detection of fault conditions and their response. The optimization of hardware and software configuration is the key feature within the VPAC framework that ensures high-speed deterministic performance for modern power systems. Benchmarking against standards: VPAC implementations are benchmarked against the performance standards specified by IEC 61850 to ensure that the VPAC implementations are indeed effective. During this rigorous testing and validation process, one can be