Two months ago, I was accepted for an internship at Proenerg (a company which focuses on power generators). Initially, I was there to see how a company is run and quite soon I become a part of their workshop team.
After only one week, I got involved in one of their new projects: a module for a generator which would charge the batteries more effectivly. This project was ordered by one of the most important clients who wanted 100 modules + generators. I decided to jump in and design a prototype based on Arduino board.
Batteries, in general, have a certain voltage when are fully charged (eg.24V) and when they are discharged, batts have a lower value (eg. 20 V). Starting from this fact, my prototype was meant to have the following specifications:
- When tension reaches the bottom level, the module should close the contact into a relay in order to start the generator which is connected to a charger that would fully charge the batteries.
- The module would monitor the batteries and would run the following algorithm:
- If (V min < V monitored < V max) does nothing;
- When (V monitored <= V min) close the relay;
- When (V monitored >= V max) relay releases;
After two weeks I came up with an Arduino shield which worked properly and passed the tests. Here is the algorithm.
The board (the module) has:
- a voltage divider in order to scale the battery voltage from 24 V down to 5 V (this is the maximum value which Arduino reads on each analog port);
- a contact relay which is closed when the generator starts;
- a relay for the electric starter motor which is closed for maximum 3 seconds and only after the contact is on;
- an alarm relay which closes after 5 failures in starting the generator;
- a 240 V relay which check the generator’s status (if it is on and charging the batteries or not).
The client was pleased with my prototype and the technicians and electricians helped me to develop the project. A production line was put in place and the integral order of 100 modules and generators was executed. I was very proud of this, as every single circuit board has a part of my innovation built-in it.
Vlad Petrescu 