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Three Phase AC Induction Motor Control with Direction Change

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ecentric70

Joined: 05 May 2012
Posts: 3
Location: West Lafayette, IN

Three Phase AC Induction Motor Control with Direction Change

Posted: Sat May 05, 2012 2:11 am

Here is some code for three phase AC induction motor control using the PIC18F2431 or PIC18F4431 (PIC18LF2431 or PIC18LF4431):

Code:

////////////////////////////////////////////////////////////////////////////////
/// Three Phase PWM Control for AC Induction Motor ///
/// by ///
/// Larry E Himes Jr ///
/// April 30, 2012 ///
/// ///
/// ECET 581 Applied Electronic Drives ///
/// ///
/// PIN A0 - AN0 is used for the Closed Loop Feedback ///
/// PIN A1 - AN1 is used for User Speed Control Input ///
/// PIN C3 - User Direction Control Switch Input ///
/// ///
/// Frequency Range Control from 20Hz to 120Hz ///
/// ///
/// Thirteen Samples per PWM Sine Wave Output ///
/// ///
////////////////////////////////////////////////////////////////////////////////

#include <18f4431.h>
#device adc=10
#fuses INTRC_IO,NOWDT,NOPROTECT,NOMCLR
#use delay(clock=8000000)

void main()
{
int16 adc_val; // ADC Variable
int16 period; // PWM Time Period Variable
int16 feedbackI; // Feedback Varaiable
int16 feedbackL; // Feedback Variable
int16 adjust; // Speed Adjust Variable
int16 speed; // Speed Control Variable
int16 i; // Counter Variable
int8 x; // Soft Start Variable

//PPWM channels 0 and 1 are both on and always opposite values
setup_power_pwm_pins(PWM_COMPLEMENTARY,PWM_COMPLEMENTARY,PWM_COMPLEMENTARY,
PWM_OFF);

// Continuously Sample ADC Channels
setup_adc_ports(ADC_CONT_A | ADC_WHEN_PPWM | VSS_VDD);
setup_adc(ADC_CLOCK_INTERNAL);

x=0; // Initial Startup

while(TRUE)
{
set_adc_channel(1); // Select ADC Channel 1
adc_val = read_adc(); // Read Current ADC Value
feedbackL=0; // Clear ADC Variable
feedbackI=0; // Clear ADC Variable
// Prepare Variables for Startup
if (x==0)
{
feedbackL=adc_val; // Initial Speed Setting
adc_val=0; // Clear ADC Variable
}
// Ramp Up Speed in Forward Direction
while(adc_val<<feedbackL && x==0 && !input(PIN_C3))
{
period = ( adc_val / 20 ) + 9; // Set PR2 for Frequency
speed = 511 - ( ( 1023 - adc_val ) / 2 ); // Set User Specified Speed
adjust=0; // Clear Adjust Variable
//add dead time for reactive loads
setup_power_pwm(PWM_CLOCK_DIV_128 | PWM_FREE_RUN,1,0,period,0,1,0);
// Phase Segment #1
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #2
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #3
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #4
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
// Phase Segment #5
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #6
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #7
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #8
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #9
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #10
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #11
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #12
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #13
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
x=1; // Ramp Up Cycle Completed
adc_val=adc_val+3; // Increment ADC Value
}
i=0; // Clear Counter Variable
feedbackL=0; // Clear ADC Variable
// Rotate Motor in Forward Direction
while(!input(PIN_C3))
{
// Read Initial ADC Values
set_adc_channel(0); // Select ADC Channel 0
feedbackI = read_adc(); // Read Initial Feedback
set_adc_channel(1); // Select ADC Channel 1
adc_val = read_adc(); // Read Current ADC Value
period = ( adc_val / 20 ) + 9; // Set PR2 for Frequency
speed = 511 - ( ( 1023 - adc_val ) / 2 ); // Set User Specified Speed
//add dead time for reactive loads
setup_power_pwm(PWM_CLOCK_DIV_128 | PWM_FREE_RUN,1,0,period,0,1,0);
// Phase Segment #1
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #2
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #3
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #4
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
// Phase Segment #5
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #6
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #7
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #8
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #9
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+speed); // Phase W PWM Duty Setting
// Phase Segment #10
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #11
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #12
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #13
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
i++; // Increment Counter
if (i>>1799) // Check Counter
{
set_adc_channel(0); // Select ADC Channel 0
feedbackL = read_adc(); // Read Feedback from ADC
adjust = feedbackI - feedbackL; // Calculate Speed Adjust
i=0; // Clear Counter Variable
}
}
i=0; // Clear Counter Variable
// Ramp Down Motor Speed for Direction Change
while(adc_val>>0 && input(PIN_C3))
{
period = ( adc_val / 20 ) + 9; // Set PR2 for Frequency
speed = 511 - ( ( 1023 - adc_val ) / 2 ); // Set User Specified Speed
adjust=0; // Clear Adjust Variable
//add dead time for reactive loads
setup_power_pwm(PWM_CLOCK_DIV_128 | PWM_FREE_RUN,1,0,period,0,1,0);
// Phase Segment #1
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #2
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #3
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #4
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
// Phase Segment #5
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #6
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #7
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #8
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #9
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #10
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #11
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #12
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #13
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
adc_val=adc_val-3; // Decrement ADC Value
x=0; // Direction Change Complete
}
i=0; // Clear Counter Variable
// Ramp Up Speed in Reverse Direction
while(adc_val<<feedbackL && x==0 && !input(PIN_C3))
{
period = ( adc_val / 20 ) + 9; // Set PR2 for Frequency
speed = 511 - ( ( 1023 - adc_val ) / 2 ); // Set User Specified Speed
adjust=0; // Clear Adjust Variable
//add dead time for reactive loads
setup_power_pwm(PWM_CLOCK_DIV_128 | PWM_FREE_RUN,1,0,period,0,1,0);
// Phase Segment #1
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #2
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #3
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #4
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
// Phase Segment #5
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #6
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #7
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #8
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #9
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #10
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #11
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #12
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #13
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
adc_val=adc_val+3; // Increment ADC Value
x=-1; // Ramp Up Cycle Complete
}
feedbackL=0; // Clear Feedback Variable
// Rotate Motor in Reverse Direction
while(input(PIN_C3) && x<<0)
{
// Read Initial ADC Values
set_adc_channel(0); // Select ADC Channel 0
feedbackI=read_adc(); // Read Initial Feedback
set_adc_channel(1); // Select ADC Channel 1
adc_val=read_adc(); // Read Current ADC Value
period = ( adc_val / 20 ) + 9; // Set PR2 for Frequency
speed = 568 - ( adc_val / 2 ); // Set User Specified Speed
//add dead time for reactive loads
setup_power_pwm(PWM_CLOCK_DIV_128 | PWM_FREE_RUN,1,0,period,0,1,0);
// Phase Segment #1
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #2
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/2); // Phase W PWM Duty Setting
// Phase Segment #3
set_power_pwm0_duty(adjust+29+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #4
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #5
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #6
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #7
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #8
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #9
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
// Phase Segment #10
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #11
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #12
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #13
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
if (i>>1799) // Check Counter
{
set_adc_channel(0); // Select ADC Channel 0
feedbackL = read_adc(); // Read Feedback from ADC
adjust = feedbackI - feedbackL; // Calculate Speed Adjust
i=0; // Clear Counter Variable
}
}
i=0; // Clear Counter Variable
// Ramp Down Motor Speed for Direction Change
while(adc_val>>0 && input(PIN_C3))
{
period = ( adc_val / 20 ) + 9; // Set PR2 for Frequency
speed = 511 - ( ( 1023 - adc_val ) / 2 ); // Set User Specified Speed
adjust=0; // Clear Adjust Variable
//add dead time for reactive loads
setup_power_pwm(PWM_CLOCK_DIV_128 | PWM_FREE_RUN,1,0,period,0,1,0);
// Phase Segment #1
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #2
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #3
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+1); // Phase W PWM Duty Setting
// Phase Segment #4
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
// Phase Segment #5
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #6
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+57+speed); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #7
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+43+speed/2); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #8
set_power_pwm0_duty(adjust+1); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+29+speed/4); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #9
set_power_pwm0_duty(adjust+14+speed/6); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #10
set_power_pwm0_duty(adjust+29+speed/4); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+57+speed); // Phase W PWM Duty Setting
// Phase Segment #11
set_power_pwm0_duty(adjust+43+speed/2); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+43+speed/2); // Phase W PWM Duty Setting
// Phase Segment #12
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+1); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+29+speed/4); // Phase W PWM Duty Setting
// Phase Segment #13
set_power_pwm0_duty(adjust+57+speed); // Phase U PWM Duty Setting
set_power_pwm2_duty(adjust+14+speed/6); // Phase V PWM Duty Setting
set_power_pwm4_duty(adjust+14+speed/6); // Phase W PWM Duty Setting
adc_val=adc_val-3; // Decrement ADC Value
x=0; // Direction Change Complete
}
i=0; // Clear Counter Variable
}
}

This code was written so that either the 28 pin or the 40 pin version can be used without code modification. The constant offsets for each PWM segment allow for better use of the PWM signal. But adding those constants puts the code limit a little beyond that of the PIC18Fx331. An array for the sine wave samples was attempted originally but the PIC would not ready quickly enough for the third phase to be implemented. That is the reason for processing the PWM settings on a line by line basis. This code also includes soft start and direction change of the three phase AC motor. Along with code to slow the motor to stop before changing direction. Addition or subtraction of 3 for the adc_val variable ensures that the motor speed up or ramp down time is not greater than six seconds. This code will work with the IRAMS06UP60A, for example. The two feedback variables are used to monitor the rotation speed at two different time instances. Any feedback of questions, comments or suggestions are welcome.

ecentric70

Joined: 05 May 2012
Posts: 3
Location: West Lafayette, IN

MicroChip Application Note AN900
Posted: Sat May 05, 2012 2:57 am

MicroChip Application Note AN900 is about three phase AC motor control using the PIC18F4431. http://www.ccsinfo.com/faq.php?page=ccs_mplab

Praful

Joined: 18 Jun 2012
Posts: 23

Three Phase AC Induction Motor Control
Posted: Mon Jun 18, 2012 3:34 am

Dear ecentric70, Can you provide circuit diagram and also can you describe how to change frequency up to 500Hz. Thanking You.

asmboy

Joined: 20 Nov 2007
Posts: 2128
Location: albany ny

Posted: Mon Jun 18, 2012 7:52 am

does this really do what you think you programmed?

int8 in CCS is by default unsigned.......

yet you assign

Code:

x=-1;

but then there is never a decision based on a value of x=-1;
anyway?
meaning it is never differentiated from x !=0
( ???? )

ALSO

i see a recurring assignment:

Code:

i=0;

but no other ref to the var ??
does it ever 'count' anything ???

BTW: learn to use the CODE button when you post

my eyes are old and tired
Laughing

SherpaDoug

Joined: 07 Sep 2003
Posts: 1640
Location: Cape Cod Mass USA

Re: Three Phase AC Induction Motor Control

Posted: Tue Jun 19, 2012 6:46 am

Praful wrote:

Dear ecentric70,
Can u provide circuit diagram also can u describe it how to change frequency up to 500Hz.
Thanking You. Cool

As a first guess I would think going from 120Hz to 500Hz would require going from a 8MHz clock to at least a 33MHz clock. First look for a PIC that can do that. Many of the newer ones go as high as 40MHz.
_________________
The search for better is endless. Instead simply find very good and get the job done.

edwinvillalta

Joined: 17 Dec 2012
Posts: 1

Re: Three Phase AC Induction Motor Control with Direction Ch
Posted: Wed Dec 26, 2012 10:52 am

Hi, ecentric70. Good job. your code Three Phase AC Induction Motor Control with Change Direction I am very interested your code I wanted to ask what program did you use to simulate your code, there will be simulated in proteus (ISIS) or some other software. and if you do not mind I would ask more information about the subject for study. Advance Thanks Att. Edwin Villalta.

Wolf

Joined: 23 Sep 2011
Posts: 32


Posted: Sat Feb 16, 2013 7:06 am

Can something be done just like this using something like dsPIC30F4011 or dsPIC30F6010A using setup_motor_pwm() rather then setup_power_pwm_pins()? I'm doing some research into maybe trying something like this with the 2 dsPIC's I had mentioned

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