Chargeur Solaire
Description
Le chargeur solaire est un dispositif complet de recharge de batterie : batterie au plomb 12V ou chargeur USB (pour smatrphone, …).
Il comprend ;
- un panneau solaire 12V nominal
- un régulateur de charge 12V pour batterie au plomb
- un convertisseur DC/DC : 12V-5V (USB)
De plus, il est instrumenté, afin de pouvoir réaliser en temps réel des mesures, et les afficher. Pour cela il comporte :
- un microcontrôleur Arduino UNO
- un capteur de courant/tension INA219
- un afficheur LCD 2 lignes
Modélisations
Maquette volumique
Document Onshape
Matériel
Programme
#include <LiquidCrystal.h>
#include <Adafruit_INA219.h>
LiquidCrystal lcd(12,11,5,4,3,2);
Adafruit_INA219 ina219;
// Variables globales
const int periodeMesure = 1000; // millisecondes
unsigned long lastMesureTime = 0;
// Menu
uint8_t menu = 4;
const uint8_t max_menu = 4;
const uint8_t BTN_PIN = 8;
int buttonState; // the current reading from the input pin
int lastButtonState = LOW; // the previous reading from the input pin
unsigned long lastDebounceTime = 0; // the last time the output pin was toggled
unsigned long debounceDelay = 50; // the debounce time; increase if the output flickers
// Grandeurs mesurées
float shuntvoltage = 0; // mV
float busvoltage = 0; // V
float current_mA = 0;
float loadvoltage = 0;
float power_mW = 0;
float E = 0.0; // Énergie (J)
unsigned long t = 0;
unsigned long t_1 = 0;
void setup() {
Serial.begin(9600);
lcd.begin(16,2);
// Initialize the INA219.
// By default the initialization will use the largest range (32V, 2A). However
// you can call a setCalibration function to change this range (see comments).
if (! ina219.begin()) {
Serial.println("Failed to find INA219 chip");
lcd.print("Echec INA219");
while (1) { delay(10); }
}
pinMode(BTN_PIN, INPUT_PULLUP);
digitalWrite(BTN_PIN, HIGH);
t = millis();
}
void loop() {
// read the state of the switch into a local variable:
int reading = digitalRead(BTN_PIN);
if (reading != lastButtonState) {
lastDebounceTime = millis();
}
if ((millis() - lastDebounceTime) > debounceDelay) {
if (reading != buttonState) {
buttonState = reading;
if (buttonState == HIGH) {
menu += 1;
if (menu > max_menu) {
menu = 0;
}
//Serial.println(menu);
afficher();
}
}
}
lastButtonState = reading;
// Mesures et affichage
if ((millis() - lastMesureTime) > periodeMesure) {
lastMesureTime = millis();
mesurer();
afficher();
}
}
void afficher() {
lcd.clear();
if (menu == 1) { //affichage du courant
lcd.setCursor(0,0);
lcd.print("Courant bat ");
lcd.setCursor(0,1);
lcd.print("I = ");
lcd.print(prefixe(current_mA/1000, 3));
lcd.print("A ");
}
else if (menu == 2) { //affichage de la tension
lcd.setCursor(0,0);
lcd.print("Tension bat ");
lcd.setCursor(0,1);
lcd.print("U = ");
lcd.print(prefixe(busvoltage, 3));
lcd.print("V ");
}
else if (menu == 3) { //affichage de la puissance
lcd.setCursor(0,0);
lcd.print("Puissance bat ");
lcd.setCursor(0,1);
lcd.print("P = ");
lcd.print(prefixe(power_mW/1000, 3));
lcd.print("W ");
}
else if (menu == 4) { //affichage de l'énergie produite sur 24h//
lcd.setCursor(0,0);
lcd.print("Energie bat ");
t_1 = t;
t = millis();
E += power_mW/1e6 * (t-t_1); // Joules
lcd.setCursor(0,1);
lcd.print("E = ");
lcd.print(prefixe(E, 2));
lcd.print("J ");
}
else {
lcd.setCursor(0,0);
lcd.print("Mesures batterie");
lcd.setCursor(0,1);
lcd.print("bouton : menu");
}
}
void mesurer() {
busvoltage = ina219.getBusVoltage_V();
current_mA = ina219.getCurrent_mA();
power_mW = busvoltage*current_mA; //ina219.getPower_mW();
Serial.println(String("U = ") + busvoltage + " V");
Serial.println(String("I = ") + current_mA + " mA");
Serial.println(String("P = ") + power_mW + " mW");
Serial.println(String("P = ") + busvoltage*current_mA + " mW");
Serial.println(String("E = ") + E + " J");
Serial.println();
}
/******************************************************************************************/
char __mathHelperBuffer[17];
char * prefixe(float f, int n) {
int pos = 0;
// Handle negative numbers
bool neg = (f < 0.0);
if (neg)
{
__mathHelperBuffer[pos++] = '-';
f = -f;
}
//Serial.println(f,4);
char p;
if (f >= 1000) {
p = 'k';
f /= 1000;
} else if (f > 1) {
p = ' ';
} else if (f > 1/1000) {
p = 'm';
f *= 1000;
}
//Serial.println(f,4);
int exponent = 0;
while (f >= 10.0)
{
f /= 10;
exponent++;
}
while (f < 1 && f != 0.0)
{
f *= 10;
exponent--;
}
//Serial.print(f,4);
//Serial.print(" E");
//Serial.println(exponent);
f *= pow(10, n-1);
f = round(f);
//Serial.println(f,4);
char digits[n+1];
int i = 0;
int e = int(f);
bool z = false;
while (i <= n) {
if (n-i-1 == exponent) {
if (z) {
digits[n-i] = '.';
} else {
digits[n-i] = '\0';
}
z = true;
} else {
if ((e % 10 != 0) || z) {
digits[n-i] = (e % 10) + '0';
z = true;
} else {
digits[n-i] = '\0';
}
e /= 10;
}
i++;
}
//Serial.println(digits);
if (digits[0] == '.') {
__mathHelperBuffer[pos++] = '0';
}
i = 0;
while ((i < n+1) && (digits[i] != '\0')) {
__mathHelperBuffer[pos++] = digits[i];
i++;
}
if (p != ' ') {
__mathHelperBuffer[pos++] = ' ';
__mathHelperBuffer[pos++] = p;
}
__mathHelperBuffer[pos] = '\0';
return __mathHelperBuffer;
}
/******************************************************************************************/
float moy_analog( int pin )
{
int valeur;
float moyenne = 0;
int nbr_lectures = 50;
for( int i = 0; i < nbr_lectures; i++ ){
valeur = analogRead( pin );
moyenne = moyenne + float(valeur);
delay(2);
}
moyenne = moyenne / float(nbr_lectures);
return moyenne;
}
