Hello Guys,
I have to make a Power Analyzer Using Arduino in which I have to show Power, Voltage, Current & Power Factor at different loads.
Now, I have designed a Voltage Sensor using this tutorial
and purchased current sensor ACS-712(20A).
I have build a program to calculate apparent power and average power but it is giving me the same value therefore, when it comes to PF it always shows 0.99 or 1.0 either on Resistive(Bulb, Energy Saver) or RL load(AC single phase motor, Fan, etc). How to resolve this issue??
To calculate the Power Factor I am using this theory:
rather than zero crossing detector.
I have attached the program. Just to clarify that in this program I have done RS-485 Modbus communication with PLC.
I have also attached the Serial Communication and HMI screen shots to make it clear to you.
#define ADC_PIN A0
#define ADCI_PIN A2
#define SAMPLING 1000
#include <modbus.h>
#include <modbusDevice.h>
#include <modbusRegBank.h>
#include <modbusSlave.h>
modbusDevice regBank;
modbusSlave slave;
#define RS485TxEnablePin 2
#define RS485Baud 9600
#define RS485Format SERIAL_8E1
float Ianalog=0,adc_max,adc_min,adc_vpp,vout,value,prev;
//Variable Decleration For RMS & Inst
float Iinst,Vinst;
double Isq,Vsq;
double Iavg,Vavg;
double Irms,Vrms;
double Prms,Pinst,PF;
double b = 0;
float VoltLevel = 3.72;
void setup()
{
//Assign the modbus device ID.
regBank.setId(1);
Serial.begin(9600);
Serial1.begin(9600);
//Add Analog Input registers to the register bank
regBank.add(30001);
regBank.add(30002);
regBank.add(30003);
regBank.add(30004);
regBank.add(30005);
regBank.add(30006);
regBank.add(30007);
regBank.add(30008);
regBank.add(30009);
regBank.add(30010);
regBank.add(30011);
regBank.add(30012);
regBank.add(30013);
//Add Analog Output registers to the register bank
regBank.add(40001);
regBank.add(40002);
slave._device = ®Bank;
slave.setBaud(&Serial1,RS485Baud,RS485Format,RS485TxEnablePin);
}
void loop()
{
int a = 0;
adc_max=0;
adc_min=1024;
for(int cnt=0;cnt<SAMPLING;cnt++)
{
//Caluclation For Instantaneous Current
Ianalog = analogRead(A2);
if(Ianalog > adc_max)
{
adc_max = Ianalog;
}
if(Ianalog < adc_min)
{
adc_min = Ianalog;
}
Iinst = abs((((adc_max-adc_min)/10023))*20*7.727-0.04);
Pinst += ((5.0/1023.0)*analogRead(A0)*(220/VoltLevel))*Iinst;
//Caluclation For Sum Of Square Current
Isq += sq( Iinst);
//Caluclation For Instantaneous Voltage
vout = (5.0/1023.0)*analogRead(A0);
Vinst = (vout*220)/VoltLevel;
//Caluclation For Sum Of Square Voltage
Vsq += sq(Vinst);
//Caluclation For Instantaneous Power
//Serial.println(String ("Pinst = ")+Vinst + " * " + Iinst + " = "+Vinst*Iinst);
}
//Caluclation For RMS Current
Iavg = Isq/SAMPLING;
Irms = sqrt(Iavg);
//Caluclation For RMS Voltage
Vavg = Vsq/SAMPLING;
Vrms = sqrt(Vavg);
//Caluclation For RMS Power
Prms = Vrms*Irms;
//Caluclation For Inst Power
Pinst = Pinst/SAMPLING;
//False Current Reading
if (Prms < 18 && Pinst < 18)
{
PF=0;
Prms = 0;
Pinst = 0;
}
else
//Caluclation For Power Factor
PF = Pinst/Prms;
if(PF == 1)
PF = 0;
if (b>2)
{
Serial.println();
Serial.println("Energy Analyzer");
Serial.println("---------------");
Serial.println();
Serial.println(String("Instantaneous Voltage = ")+ Vinst + " Vac");
Serial.println(String("Instantaneous Current = ")+ Iinst + " Iac");
Serial.println(String("Average Voltage = ")+ Vavg + " Vac");
Serial.println(String("Average Current = ")+ Iavg + " Iac");
Serial.println(String("RMS Voltage = ")+ Vrms + " Vac");
Serial.println(String("RMS Current = ")+ Irms + " Amp");
Serial.println(String("Average Power P = ")+ Pinst + " Watt");
Serial.println(String("Apparent Power S = ")+ Prms + " VA");
Serial.println(String("Power Factor PF = ")+ PF + " ");
Serial.println();
b=0;
}
double Intiger=0,fract=0;
double Intiger1=0,fract1=0;
double Intiger2=0,fract2=0;
double Intiger3=0,fract3=0;
//fract = 0;Intiger=0;
//fract= modf (Vrms, &Intiger);
//fract = fract*100;
regBank.set(30001, Vrms); //from 0 - 1023
//regBank.set(30002, (word) fract); //from 0 - 1023
fract= modf (Irms, &Intiger);
fract = fract*100;
regBank.set(30003, Intiger); //from 0 - 1023
regBank.set(30005, fract); //from 0 - 1023
fract2= modf (Prms, &Intiger2);
fract2 = fract2*100;
regBank.set(30007,Intiger2); //from 0 - 1023
regBank.set(30009,fract2); //from 0 - 1023
fract3= modf (PF, &Intiger3);
fract3 = fract3*100;
regBank.set(30011,Intiger3); //from 0 - 1023
regBank.set(30013,fract3); //from 0 - 1023
b++;
Iavg=0;
prev=0;
Vsq = 0;
Isq = 0;
Pinst = 0;
slave.run();
delay(100);
}
/*
* abs(((((adc_max-adc_min)/2)*(20*1.74))/1023)-0.05);
* /2 = mean
* *20/1023 = 0.01955
* -0.05 = callibration
*/
Power_Analyzer.ino (4.82 KB)
