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Based on the development of new technologies in the electrical engineering field, microgrids can be understood as the effective implantation of smart grids. These, in turn, have functionalities for energy management, such as voltage control, frequency, and demand management, and can also operate in a connected or island mode concerning the utilities resources. In the face of such technological advances and energy management, this paper presents a proposal for the implementation of a microgrid, called CampusGRID. This microgrid will be installed on the University Campus of UNICAMP - Brazil, being connected to a 11.9kV level voltage grid with 2370 kVA power rated shared among eleven points of connections and demand varying from 475 to 768 kW. For the control of loads (electric vehicle, classroom buildings, laboratories, libraries, convention center, multidisciplinary gymnasium), it is proposed to automate the circuits in the secondary side of transformers to control the loads, as well as the monitoring of these. For the power generation system, a set of distributed energy resources (DER) was considered, such as photovoltaic sources (PV), sources with cogeneration known for the combination of heat and power (CHP) using natural gas and storage system with lithium-ion batteries. These energy resources will be controlled by a centralized energy management system, with fiber-optic network communication, ensuring signal synchronism to the equipment for the provision of services, as well as serving as a means to collect the data set from the respective equipment for studies and performance improvements of the CampusGRID microgrid. Keywords: Microgrid; DER; EMS; Smart Grid;

This paper evaluates the impact of voltage distortion on the electrical quantities measured by revenue meters and the influences on the electrical energy billing. This is done through an experimental setup, which combines the following variables for the first time in an experiment: different total harmonic voltage distortion (THDv) levels; among these levels, different harmonic profiles; and different loads. A programmable alternating current (AC) power source was used in the laboratory to apply voltage signals in three electronic loads: a compact fluorescent lamp (CFL) and two light emitting diode (LED) lighting devices for which voltage signals with THDv 4.9%, 18.8% and 24.5% have been applied. All applied signals contain one or more harmonic order more commonly found in the low voltage grid (3rd, 5th and 7th). For these analyses, a power quality analyzer and a revenue meter were used. The results show that significant and diverse effects on the electrical quantities of individual loads will occur with different THDv levels and harmonic profiles. Comparing with a reference case (sinusoidal condition), when a distorted signal was applied, for the same THDv level, some parameters remained numerically the same, some have improved and some have become worse. This study shows that the effects of combination of the variables such as different THDv level with different harmonic profiles on electrical quantities of loads are not as clear as the effects of considering only one variable. The results of this paper shed light on such effects.

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One of the challenges faced by Brazilian distribution utilities to enable the connection and operation of microgrids (MGs) is the absence of a solid set of technical standards in the country. An alternative has been to use and adapt existing standards applied to micro- and mini-distributed generation. In this context, this paper presents an analysis of the development status of norms, standards, and general requirements for the connection and operation of microgrids, as well as a proposal for the regulation and structuring of technical and operational requirements related to the implementation of microgrid projects. Some critical points highlighted in the paper include: the modes of operation, the minimum requirements for the different modes of operation, interoperability of systems, a conceptual model with attribution of responsible actors for the decentralized management of microgrids adapted to the institutional standards of the Brazilian sectorial model, a proposal for a standard connection structure considering the point of connection (PoC) implanted using multifunctional relay and recloser, procedures for technical feasibility assessment (operational studies) of MGs connection, and, finally, a discussion of operational issues of storage systems in a microgrid environment.