Abstract
Renewable energy is one of the most abundant energies in our planet. In order to satisfy the world demand of electrical energy, solar and wind energy may be used. Identical to all other types of power generation plants, the integration of these renewable energy sources in smart power grid has an impact on its operation. Thus, when the electrical power is injected into the power grid by these energy sources, the system electrical parameters must be well monitored for synchronization purpose. This can be accomplished with the aid of synchro-phasors measurement units. The phase angle of the utility is a critical parameter for the operation of power devices feeding power into the grid such as PV and wind energy inverters. There are many techniques to obtain the grid phase angle such as the zero-crossing detection and the orthogonal phase locked loop. This research work discusses the use of PMUs (Phasor Measurement Unit) for providing this important parameter to system synchronization in the case of high penetration of solar or wind energy in the power grid.
TopLiterature Survey
In the late seventies, the oil crisis caused a drastic increase in the demand of renewable energy sources. This increase has been driven by the remarkable advantages offered by these kind of energy sources namely free resource, infinite reserve and clean conversion process. However, till today, the fuel is still the main source of energy in most power generating systems. While, global warming and energy policies have become a hot topic worldwide. Developed countries are trying to reduce their greenhouse gas emissions. For instance, the European union has committed to reduce their greenhouse gas to at least 20% levels before 1990 and to produce no less than 20% of its energy consumption from renewable sources by 2020 (European Commision, 2020). In fact, the secured and safe integration of renewable energy (RE) resources including wind and solar energy to the main grid is one of the biggest challenges for the world energy sector today (Ahmada, T., 2020).
Among all renewable energy sources, the solar energy is the fastest growing electricity source in the last decade. It is also considered as the cleanest source ever. It can be produced either off-grid or tied to the grid; grid-connected. As a matter of fact, most of the PV power generation comes from grid-connected installations, where the power is fed in the electricity network.
Key Terms in this Chapter
Phasor Measurement Unit (PMU): PMU is a measurement device, developed in mid 1980s. It measures the electrical quantities such as voltage and current at node in the power system where it has been installed. It provides the real time phasor parameters of these quantities such as magnitude, frequency, phase angle and rate of change of frequency.
Smart Power Grid: A smart grid is an electrical grid which includes a variety of operation and energy measures including smart meters, smart appliances, renewable energy resources, and different energy resources.
Zero-Crossing Detection: it is based on converting the feedback sinusoidal grid signal to an equivalent square wave signal, compare it to the ground and generate a pulse each time a rising edge is detected; it generates an equivalent periodic pulse representing its frequency.