## 1 Introduction
The future objective of this research is to maintain a data flow between the physical and the synthetic installation in both a deterministic way and in real-time. Using Hardware-In-the-Loop (HIL), models can evolve with latencies in line with the installation. This type of technology is becoming increasingly relevant for the development of digital twins [7]. It is in a constant process of development in the energy sector [8]. With the Network Time Protocol (NTP), it is possible to synchronise the clocks of any monitoring system with one of the many existing NTP servers based on the Coordinated Universal Time (UTC). Currently, with NTP v4, it is possible to achieve synchronisation levels close to 10 ms. Conversely, with the PTP v2 protocol, uncertainty levels of less than 1 ms are achieved and it is specially designed for distributed synchronisation in industrial applications [9]. Despite these improvements, with these uncertainty levels, it is not feasible to coordinate a simultaneous capture for distributed acquisition systems. In contrast, with the TSN standard, simultaneous sampling in distributed systems is possible since the clocks would be synchronised with uncertainty levels below 100 ns. This paper evaluates a new alternative to the various existing proposals [10; 11] to extend very high-quality synchronism from \(\upmu\)PMUs to other equipment to correlate events inside the generation facility, with disturbances propagating in the network. To achieve this objective, a technological improvement of \(\upmu\)PMUs is proposed with the integration of synchronism based on TSN. It is an alternative to other proposals that use other options such as Multi-level Time-Sensitive Networking (mTSN) [12]. Subsequently, storage in a local database to facilitate Edge-Cloud Computing is proposed [1]. Furthermore, this method can contribute to the coordinated management of small \"power plants\" so these can cooperate, acting as a single generation system. With these expectations, the \(\upmu\)PMU [13; 14] will serve to maintain a single high-quality time reference frame. The \(\upmu\)PMU will act as a TSN master to extend the synchronism to the rest of the measurement systems. The technical feasibility of this method must be assessed according to the specifications of IEEE C37.118.1a-2014 [15], which relaxes the requirements concerning the general specifications for phasor monitoring [16], as included in IEEE C37.118.1-2011 [16]. There is a methodology in the \(\upmu\)PMU System Calibration and Test Guide for Power System Protection and Control [17] that allows for the verification of the feasibility of the proposed distributed synchronisation system. This guide is based on the IEEE Std C37.238\({}^{\text{TM}}\)2011 standard that focuses on defining the specifications of the IEEE 1588-2008 standard [18] for use in power systems. It is an appropriate guideline for this work considering that the IEEE 802.1 AS-2011 [19] standard is based on the previous one. As a solution for the digitisation of PV plants with distributed synchronism, the PV installations would be managed by a TSN master integrated as part of the \(\upmu\)PMU. The monitoring of the PV plant could be managed as a stand-alone system in a local area sub-network. For example, when running the IEEE 802.1 AS profile in one of the subsystems, the devices that carry out the measurements and critical control take advantage of the TSN synchronisation, while the subsystems with non-critical tasks do not work with this synchronisation but share the same gateways. National Instrument (NI) compactDAQ devices are suitable for building high-quality distributed measurement systems with in-line topology. They are not only compatible with the standard but they also include a switch with two TSN Ethernet ports for easy connection. Furthermore, the TSN standard is evaluated for its ability to achieve the accuracy required by \(\upmu\)PMUs for phase measurements.