An advanced approach has been developed to monitor and control small grids for better power utilization and fault detection. Power available at the grid which can come from multiple sources like solar, power plants, generators can be feed to the users intelligently. Depending upon the availability of power, it can be distributed priority wise among different types of users like hospitals, street lights, water pumps etc. All the related decision has been taken by a centralized control system or a smart system controller called Multi Utility Controller.
It not only includes operational controls but also energy measurement elements to analyze for better power distribution. Various parameters and usage information can be fetched using Power Line communication (PLC) from various smart utility meters like energy meter, gas meter, and water meter to generate bills and manage tariffs. The same controller can be used to communicate with street lights wirelessly for better usage and troubleshooting. This can help in saving power by controlling On/Off, light intensity remotely. All gathered information can be uploaded on server using LAN or GPRS connectivity for power analysis.
In developing countries like India, most of the population lives in small villages which have very limited availability of electricity or even does not have electricity at all. Smart Nano grid is the only solution to make them self-dependent for electricity and to face current challenges. These are digitally monitored energy systems that deliver electricity, water, gas from generation sources to points of consumption.
They optimize power delivery and facilitate two-way communication across the grid, enabling end-user energy management, minimizing power disruptions and transporting only the required amount of power. The result is a lower cost to the utility and the customer, more reliable power, and reduced carbon emissions.
Smart Nano Grid Architecture
Nano grids are very small grids to serve a building or village with few number of houses with a typical load of 100 kW for grid-tied systems and 5 kW for remote systems not interconnected with a utility grid. In the current architecture, smart grid controller has been proposed which not only handles the power distribution but also control and monitor smart street lights. All the utility meters like energy meter, gas meter, water meter etc. are also connected with this controller for billing and other consumption analysis.
Smart Nano Grid Key Components
1. Multi Utility Controller
2. Load Dispatch Controller
3. Street Light Controller
4. Smart Utility Meters
Multi Utility Controller (MUC) is an adaptable controller system for a smart Nano-grid environment. It is a portable in size and battery operated so that utility worker can keep it along with him in the field. It has a LCD display to monitor the status of the grid and a user interface for grid control. Multiple type of communication protocol are available to communicate with different types of utility meters. All the gathered information is then uploaded on the server.
Load Dispatch Controller delivers power to different houses depending upon the power available. It has multiple relays to control the electricity delivery of each house. Status of all the houses and current power parameters like voltage, current has been sent to MUC using wireless communication. MUC analyze these parameters and sends command to load dispatch controller to control the distribution of available power.
Street Light Controller is a controller system for managing street lights using wireless communication. It is a battery operated system which takes its power from solar light for charging & then to run the LED light at night. It has the intelligence to monitor different system faults and then to send fault status to MUC.
Smart Utility Meters reads various usage information including total consumption parameters, instantaneous consumption, tariff-wise consumptions etc. along with configuring various parameters i.e. Configuration parameters, maintenance parameters, tamper management, tariff settings etc. sub–1GHz wireless communication or wired Power Line Communication helps meters communicate directly with MUC.
MUC System Architecture
MUC system has been designed around STM32F4 series microcontroller from STMicroelectronics. It is the high-performance ARM®Cortex-M4 32-bit RISC core operating at a frequency of up to 168 MHz suiting for this application. On chip 1 Mbyte Flash memory along with 192 Kbytes of SRAM met the memory requirements.
A 7.0 inch Amorphous-TFT-LCD (Thin Film Transistor Liquid Crystal Display) with a Resolution of 480(R.G.B) X 234 pixel is used to display the various parameters and to take the required inputs. MCU’s on Chip FSMC peripheral has been used to interface the LCD display.