<abstract> <p>Sudden variability in solar photovoltaic (PV) power output to electrical grid can not only cause grid instability but can also affect power and frequency quality. Therefore, to study the balance of electrical grid or micro-grid power generated by PV systems in an upstream direction, predicting models can help. The power output conversion is directly proportional to the solar irradiance. Unlike time horizons predictions, many technics of irradiance forecasting have been proposed, long, medium and short term forecasting. For the Island of Mauritius in the Indian Ocean, and regards to key policy decisions, the government has outlined its intention to promote the PV technologies through the local electricity supplier but oversee the technical requirements of PV power output predicts for 1 hour to 15-minutes ahead. So, this paper is illustrating results of the Johansen vector error correction model (VECM) cointegration approach, from the author original and previous studies, but for a very short term prediction of 15-minutes to PV power output in Mauritius. The novelty of this study, is the long run equilibrium relationship of the Johansen model, that was initially determined in previous research works and from dataset in Reunion Island, is then applied to the PV plant in the Island of Mauritius. The proposed prediction model is trained for an hourly and 15-minutes period from year 2019 to year 2022 for a random month and a random day. The experimental results show that the performance metric R<sup>2</sup> values are more than 93% signifying that Johansen model is positively and strongly correlated to onsite measurements. This proposed model is a powerful predicting tool and more accuracy should be attained when associated to a machine learning method that can learn from datasets.</p> </abstract>

A small island power system, such as that of Mauritius, has, by definition, a low inertial response, making it highly sensitive to network disturbances, occasioned, for instance, by the loss of generating units or sudden increases of demand. This is why, the integration of intermittent renewable energy is a major challenge, which the Central Electricity Board (CEB) is facing in its effort to reduce fossil fuel in its energy mix, Synchronous generators contributing to the overall system inertia will be replaced by renewable energy with a resultant increased exposure to grid frequency instability. Moreover, short circuit levels will be eroded by the new trend, introducing new complications to protection coordination. Solutions for satisfactory regulation are battery storage, drop mode operation of residue synchronous generators and the enforcement of output forecasts in RE contracts. New impedance values will influence short circuit currents. As a result, new modern smarter protection technologies will be necessary.

High quality electrical service is key to power systems around the world, particularly in utilities and industrial facilities. Both voltage and grid frequency must be kept within tight limits to maintain functioning of critical infrastructure. The growing use of renewable power of intermittent character is adding to that challenge. One of the keys to achieving quality service is the protection system, which needs to be reliable, fast and with a good cost/benefit ratio. It consists of various components, including relays, circuit breakers and fuses. An understanding of the different behaviours of these components in the face of malfunctions, and of countermeasures, is needed. This book has established itself as a classic work in its field, allowing the reader to easily follow the ideas explored. It provides an overview of most aspects of electrical protections, with emphasis on distribution systems; but protection of generation and transmission systems are also addressed. For this 4th edition, new topics have been added, such as protection of renewable power plants and transient stability analysis. It offers a thorough revision of the material, particularly the numerical type of relays, protective functions, control, measurement, communications and oscillography features. Most chapters have illustrative examples using MATLAB or PSAT (Power System Analysis Tools). This work remains essential reading for researchers, utility engineers, design, maintenance and consulting engineers as well as for instructors and senior students.

In the offshore wind industry, failures are often costlier than those experienced onshore. Through examination of the literature, it is clear that failures occurring in offshore transmission systems are not well documented. As a result of this, many developers and other parties involved in the planning processes associated with offshore wind farms will defer back to existing reliability metrics in the public domain. This article presents a review of European offshore wind farm transmission failures based on fusing information from multiple public domain sources. The results highlight both the spread of the reliability performance of these assets and the reliability performance over time. The results also reinforce the industry view that installation practices could lead to low reliability in the initial years of operation, resulting in increased repair costs and decreased revenue for wind farm owners and operators. The information collated in the review is also compared to metrics from across the literature to evaluate the difference in forecasted failure rates to those experienced within the industry. In general, it is found that the experienced failure rates are subject to a much higher spread in practice than those published until now.

This paper presents an energy efficiency labelling system for industrial motors used in Sri Lanka. Industrial sector in Sri Lanka consumes 3,880 GWh of electricity, i.e. 33% out of 11,741 GWh of total electricity consumption (2015). Induction motors account for a high share of energy used in industry. The energy efficiency labelling system proposed will enable improved efficiency of industrial motors by reducing energy losses. The automatic efficiency testing program is developed using the LabView development platform based on IEC 60034-2-1 standard. Subsequently, a test bench design was also developed. It will be helpful in purchasing motors from the international market and thereby motor driven systems will achieve the next level of efficiency in the industrial sector. It also helps to cross check the efficiency level of repaired or rewound motors. An economic calculation model (tariff based) is developed to analyse the economic benefits of higher efficiency levels. This economic calculation model assists in decision-making of replacement of a motor or an upgrade of a system.