Didactic smart grid system. The “Grid”, refers to the electric grid, a network of transmission lines, substations, transformers and more that deliver electricity from the power plants to home or business. The digital technology that allows for two-way communication between the utility and its customers, and then the sensing along the transmission lines is what makes the grid Smart. The Smart Grid consists of controls, computers, automation, new technologies and equipment working together, able to calculate the consumption of the various end users and to manage the generation and distribution of electricity according to demand. For this important topic, De Lorenzo has developed a modular laboratory for the study of the concepts related to; it simulates the generation of energy from three different sources (thermal, hydroelectric and wind farm), its transmission and distribution by means of high voltage lines simulation models and its utilization including small PV solar energy plants for domestic use. It is also available an option to integrate, beside the PV solar system, a wind energy modular trainer to connect to the mains network from the end user’s side. Of course, a SCADA software provides the acquisition, storage and monitoring of the data along the whole system. It is especially designed for university students and engineering graduates.
The smart grid system developed by De Lorenzo can be organized
in eight subsystems, each comprised of
several modules. 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. The 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, current s, 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 measurement s of DC voltage, current, power and energy.
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 fac tory 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 system. The SCADA software can also be supplied on requ est 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 actuators.
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.
Didactic system for the study of the generation of electric energy from a wind turbine and its inlet in the
The device includes a set of control modules, measures and applications, a wind turbine, a stepper motor to drive the wind generator in absence of wind and descriptive and practical manuals.
The system is composed of the following modules:
• Module for measuring electric and wind parameters
• DC/AC conversion module
• Braking resistance, 250 W, 3 Ohm
• Mains lamps module
• Energy measurement module
• Differential magneto‐thermal switch
• Network distributor
• Motor kit for driving the wind turbine, composed of a stepper motor and a 300 W power supply
• Wind generator: 400W, 12Vac
• Wind sensor: Anemometer and wind direction sensor mounted on a stand
It also includes:
• Two level frame
• Set of interconnecting wires
• Descriptive and practical manual
• Wind turbine instruction manual
The trainer includes a software for data acquisition and processing.