Integration Monitoring of On-grid Photovoltaic System: Case Study

The aim of the paper is to present possible using of monitoring systems associated with photovoltaic systems (PV) in point of its integration with electrical power system (EPS). Presented investigations is a case study of 15 kW Scientific Photovoltaic System. The paper contains a description of applied control and monitoring systems including monitoring of PV panels parameters, weather condition, PV DC/AC inverters as well as special monitoring systems dedicated to power quality (PQ) and shape of voltage and current. The aim of the paper is to exhibit a possibility to combine different monitoring systems of the PV in order to improve evaluation of integration of PV with EPS. Presented example contains selected elements of power quality assessment, power and energy production, weather conditions for selected period of PV system working time

A Case Study on Distributed Energy Resources and Energy-Storage Systems in a Virtual Power Plant Concept: Technical Aspects

The article presents calculations and power flow of a real virtual power plant (VPP), containing a fragment of low and medium voltage distribution network. The VPP contains a hydropower plant (HPP), a photovoltaic system (PV) and energy storage system (ESS). The purpose of this article is to summarize the requirements for connection of generating units to the grid. Paper discusses the impact of the requirements on the maximum installed capacity of distributed energy resource (DER) systems and on the parameters of the energy storage unit. Firstly, a comprehensive review of VPP definitions, aims, as well as the characteristics of the investigated case study of the VPP project is presented. Then, requirements related to the regulation, protection and integration of DER and ESS with power systems are discussed. Finally, investigations related to influence of DER and ESS on power network condition are presented. One of the outcomes of the paper is the method of identifying the maximum power capacity of DER and ESS in accordance with technical network requirements. The applied method uses analytic calculations, as well as simulations using Matlab environment, combined with real measurement data. The obtained results allow the influence of the operating conditions of particular DER and ESS on power flow and voltage condition to be identified, the maximum power capacity of ESS intended for the planed VPP to be determined, as well as the influence of power control strategies implemented in a PV power plant on resources available for the planning and control of a VPP to be specified. Technical limitations of the DER and ESS are used as input conditions for the economic simulations presented in the accompanying paper, which is focused on investigations of economic efficiency