Auto Load Shedding Time Management System
Electric utilities load shed when there is huge demand for electricity exceeding supply or if power generated is less than the consumers demand, the need to shed load is eminent in order to avoid total breakdown of equipment’s used by power distribution companies as a result of overloading effect. So, this project is about automatic load management system for optimized and automatic load shedding.
Introduction to Load Management:
This design is focused on time management automatic load shedding system, its aim is to automatically switch ON/OFF different load distribution lines multiple number of times. This system is takes over the manual task of switching ON/OFF of power distribution lines with respect to time this way load is shared to different areas or regions with respect to time as it helps to define user load priority and groups.
The system uses real time clock (RTC) interfaced to an Arduino UNO ATMEGA328 series microcontroller, while the set time equals the real time, the microcontroller gives command to the corresponding relay to turn ON the load and then another command to switch OFF as per the program. Multiple ON/OFF time entry is the biggest advantage with this project.
Push button switches are being used in this project to set up the control and also used to enter the ON/OFF time. A liquid crystal display (LCD) is interfaced to the microcontroller for displaying every information needed to setup the device.
Areas of Application:
This Project can be used in:
- Power distribution companies to shed load automatically, reduce downtime for critical loads, reduce spinning reserve requirements etc.
- Implemented in factories to manage the ON/OFF time of different generator sets.
- Our homes to switch ON and OFF different generator set.
Principle of Operation of Automatic Load Management System:
This project time management automatic load shedding system consist of 12v stepdown transformer, bridge rectifier, voltage regulator, ATMEGA328 microcontroller, LCD, real-time clock and push button switches.
Once there is an AC supply to the 12v transformer, it passes through the bridge rectifier which converts the AC voltage to DC voltage and the lm705 voltage regulator regulates the voltage to 5volts maximum and it supplies voltage to the LCD, microcontroller, real time clock and relay unit, the LCD displays date and time and the middle push button switch is used as menu switch while the other two switch is used to adjust the real time and date, the load ON time and OFF time, the relay for load and the days it will be ON, while the LCD shows all the necessary information of Load Management System.
Once the set-time equals the real time the corresponding relay get energized and turn ON the load connected to it.
(if you are new, best article to read before is Arduino Timers and interprets)
Hardware Design of Automatic Load Shedding Management System:
- Voltage regulator 7805
- Integrated circuits
- Liquid crystal display (LCD)
- Push button switch
- Real time clock DS12887 RTC
Design of Circuit:
Proteus electronic software was used in simulation of the circuit. This software allows for design moderations likewise other software’s such as livewire etc. The entire circuitry is subdivided into Six Units as shown below:
Power Supply Unit:
Power supply to this circuit is taken from any of these three source (public power supply, Generators or Inverter) and it is fed into the primary of a stepdown transformer within the power unit’s circuitry which is being rectified and filtered. The filtered output powers the system thereby enabling other operations.
The microcontroller unit is an essential part of the circuitry, here all the codes are compiled. This controls the activities of all other sections of automatic Load Management System such as:
Real Time Clock Unit:
The real time clock is an electronic chip that provides the real timing for the circuit.
Digital Display Unit:
The digital display unit uses liquid crystal to show the operation and working of the circuit.
This unit receives signal from the microcontroller which controls the output(s) automatically for Load Management System.
The system control is done by the firmware. Its source code is written in assembly language and assembled using the Arduino Software IDE and burnt on to the Arduino microcontroller program memory.
****The program code can be found in the supporting document***