WHY A SMART GRID?
TSince the early 21st century, opportunities to take advantage of improvements in electronic communication
technology to resolve the limitations and costs of the electrical grid have become apparent.
WHAT IS A SMART GRID?
Technological limitations on metering no longer force peak power prices to be averaged out and passed on
to all consumers equally.
In parallel, growing concerns over environmental damage from fossil fuel-fired power stations has led to a
desire to use large amounts of renewable energy.
Dominant forms such as wind power and solar power are highly variable, and so the need for more
sophisticated control systems became apparent, to facilitate the connection of sources to the otherwise
highly controllable grid.
Power from photovoltaic cells (and to a lesser extent wind turbines) has also,
significantly, called into question the imperative for large, centralised power stations.
The rapidly falling costs point to a major change from the centralised grid topology to one that is highly
distributed, with power being both generated and consumed right at the limits of the grid.
Finally, growing concern over terrorist attack in some countries has led to calls for a more robust energy
grid that is less dependent on centralised power stations that were perceived to be potential attack targets.
The Smart Grid is a system for an "intelligent distribution" of electricity, able to know the consumption of
the various end users and to manage the generation and distribution of electricity according to demand.
Simply put, if in a given area we have a potential overload of energy, the excess energy can be redistributed
to other areas that need it, based on the actual requests from end users.
Furthermore, the software that runs the Smart Grid monitors the electrical flow of the system, integrates
renewable energy into the network and activates / suspends the industrial or domestic processes during
periods when electricity costs less / more.
The smart grid knows our requirement of power consumption. When the demand for electricity is at its
maximum, the smart grid automatically adapts to the demand by picking up excess energy from many
sources to avoid overload problems or interruptions of power.
It has, therefore, the function of sharing the electricity that is generated from various sources, both public
and private, traditional and renewable, and ensuring that electrical devices use electricity as efficiently as
WHAT IS A SCADA SOFTWARE?
The SCADA (Supervisory Control And Data Acquisition) is an industrial control system that performs the
• acquisition of the physical quantities that are needed for the control and the supervision of the
• control, by means of actuators, of its operation;
• supervision, to visually monitor, through the so termed synoptic diagrams, the operating status of
the system, the alarms, etc., also in remote control.
SCADA systems supervise, control, optimize and manage the systems for the generation and transmission
of electrical energy as well as the distribution networks.
They allow to collect, store and analyze data from hundreds of thousands of data points in national or
regional networks, to model networks, to simulate operations, highlight faults, prevent them and finally
participate in the energy markets.
They are a vital part of modern networks and enable the development of the smart grids that must handle
enormous amounts of energy from renewable sources produced by generators of large and small scale, to
maintain stability in the network despite the intermittency of these sources and the bidirectionality of the
DE LORENZO SOLUTION
The smart grid system developed by De Lorenzo can be organized in eight subsystems, each comprised of
The first four subsystems are simulations of energy sources; the first one is the main
power supply of the grid with a three-phase supply unit that represents a coal plant.
The other three subsystems correspond to alternative sources of energy: wind, hydroelectric and solar.
wind plant simulation is made with a three-phase induction motor acting as a generator while the
hydroelectric plant simulation is made with a three-phase synchronous machine, additionally with a
generator synchronizing relay module to make possible the connection to the grid.
Finally, the solar energy
part of the system is generated with a solar panel and four dimmable lamps simulating the sun, which is
connected to an inverter module that allows the energy generated to be transferred to the grid.
A fifth subsystem in the smart grid consists of modules for fault protection; the modules are a feeder
manager relay that measures in real time voltages and currents to detect faults in the grid and four power
circuit breakers controlled by the previous module to disconnect faulty lines.
The sixth subsystem refers to modules for measuring; it has three maximum demand meters that measure
AC voltages, currents, frequencies, active power, reactive power, apparent power, power factor and THD
for each of the three available phases in the grid and two electrical power digital measuring units that,
besides measuring the same as the previous module, make measurements of DC voltage, current, power
The seventh subsystem is for power factor control with 2 modules, the first one is a switchable capacitor
battery with four different values of capacitors and the second one is a reactive power controller that
activates the capacitors of the previous module to make a power factor correction.
The last subsystem is composed of passive elements; three modules with different kind of loads (capacitive,
inductive, resistive) that simulate the loads in a house or factory and two modules with impedances
simulating the losses generated in transmission lines, specifically in lines of 10 and 100 km length.
A SCADA software provides to the acquisition and storage of the data coming from the measurement
instruments and to the control of the actuators for an “intelligent” management of the whole electrical
The SCADA software can also be supplied on request in an OPEN version, so that the teacher can
implement his own project and select modes and procedure for visualizing the parameters and controlling
The system described above represents the basic configuration of our laboratory (DL SGWD).
Optionally, it is also possible to add an additional wind energy small scale generation system, with a real
wind turbine connected to an inverter module to make possible the connection to the grid.