Tutorials

3rd Solar Integration Workshop Tutorial
"Technology, Design and Exploitation of PV Power Plants"


NAME AND AFFILIATION OF PRESENTERS:

Pedro Rodriguez, Prof.
Abengoa, Abengoa Research, Spain
Email: pedro.rodriguez@research.abengoa.com

Remus Teodorescu, Prof.
Aalborg University, Institute of Energy Technology, Denmark
Email: ret@et.aau.dk

Dezso Sera, Assoc. Prof.
Aalborg University, Institute of Energy Technology, Denmark
Email: des@et.aau.dk

Tamas Kerekes, Assoc. Prof.
Aalborg University, Institute of Energy Technology, Denmark
Email: tak@et.aau.dk

About Tutorial Presenters and Presenters' Institutions (PDF)

ABSTRACT AND OBEJECTIVE.-

PV technology has experienced a fast development in the last years. The prices of solar modules, inverters and other components have fallen radically, which has contributed to change the image of the PV technology from a "too expensive" technology to a cheap generation technology, with quick installation and low-maintenance. The easy scalability of the PV technology allows designing PV power plants with no real limit to the size, so we could see bigger and bigger projects in the future.

The objective of this tutorial is to offer a comprehensive review of essential aspects involved in the design and exploitation of modern PV power plants, covering both technical and operational aspects. A review of the PV panels technology will offer a vision of the PV technology currently installed by integrators, as well as presentation of the most promising new trends in PV cells. The elements in charge of processing power in PV power plants, inverters will be presented by describing both their hardware and control structures. A special attention will be paid to the control system of grid-interactive PV power plants. The synchronous power control concept will be presented as an effective solution to effectively integrate PV power plants in distributed power systems. Design of PV plants will be also covered in this tutorial, including design optimization aspects. Finally, the methodology for defining a business model, considering the influence of both technical and financial factors along the life-cycle of the PV power plant, will be presented.

AUDIENCE.-

This tutorial is intended to electrical and control engineers and researchers dealing with distributed generation and interested in going deeply into essential issues related to the design, integration and exploitation of PV power plants.

OUTLINE.-

The tutorial will be organized in five lectures covering the following topics:

PV panels

This lecture will start by conducting a review of PV cell technologies, including crystalline silicon, thin-film, and multi-junction cells, and even presenting some embryonic technologies, such as dye and organic cells. After that, modeling techniques for PV cells, modules and plants will presented and their characteristic parameters will be identified. This will allow presenting some techniques for characterizing PV panels. Finally, diagnosis techniques based on I-V curve analysis and imaging techniques for detecting degradation processes and faults, which are crucial aspects for maintenance activities and optimum yield, will be presented.

PV inverters

Inverters are a key element in PV power plants. This lecture will review the topology of the inverters commonly used in PV plants with focus on efficiency, ranging from low-power modular inverters to central inverters used to process power of large strings. Some examples from PV inverters manufacturers will be presented. The main structure of the control system of a generic PV inverter will be also presented in this lecture, as well as the most common functionalities regarding monitoring and diagnosis. Once inverter structure and control are reviewed, some simplified models including efficiency, reliability and availability to be used in the design of PV power plants will be presented.

PV plants control

This lecture deals with control aspects of PV power plants are considered. The control structure of a PV power plant will be presented, as well as the interactions between the PV plant operator, the system operator and the utility. New trends in the IEC 61850 standard regarding advanced PV power plants management functions will be presented. Regarding grid connection, new trend in grid codes, which demand PV plants to participate in grid regulation in a similar manner as conventional synchronous generators do, will be discussed. This lecture will pay special attention to modern control techniques for PV power plants based on synchronous power concepts, which improve the interaction with the electrical grid and guarantee the effective integration of the PV plants. Relevant study cases to demonstrate the effectiveness of the synchronous power control technique, at both the transmission and the distribution levels, will be presented.

PV plants design

This lecture is focused in presenting technical issues related to the design of PV power plants, as well as some aspects regarding design optimization. The lecture will start by presenting some techniques and tools for solar resource evaluation and providing design guidelines for PV module selection and PV array configuration. Possible solutions regarding PV inverter sizing and cabling layout will be presented, including additional electrical equipment, such as transformers and protections. Some relevant aspects regarding power losses analysis, yield evaluation and performance ratio will be also provided, in order to justify some cost functions for optimizing the design of the PV plant. Finally, an example of an optimization procedure for maximizing energy production and minimizing power losses in the PV power plant will be presented.

PV plants economics

This lecture introduces the methodology used to analyze financial requirements and returns of a PV plant, as well as the technique for managing uncertainties, in order to design the business model of a given project. Techniques for designing energy and cost models that allow understanding the economic impact of engineering decisions in a PV plant project will be presented. This lecture will introduce the methodology for handling the wide variety of parameters considered in complex cost of energy calculations in order to make decisions regarding economic optimization along the life-cycle of the PV plant. Finally, this lecture will provide master guidelines to design a business model for the PV plant that allows allocating costs and incomes, considering performance predictions and risks, and estimating the profits resulting from the operation of the PV power plant.