emeter_3ph_background.c

TI三相电能表源程序

                                        //get rid of CT delay for the current
  I_sample=FIR(chan2_int_params,I_sample);  
                                        //store into buffers                                  
  current_buffer_chan2[samples_write_index]=I_sample;                                        
  voltage_buffer_chan2[samples_write_index]=V_sample;
  
//if(samples_write_index>=SAMPLE_BUFFER_SIZE)
//  samples_write_index=0;                                        

//****************************************************
//  Now comes the reading part, both current and voltage is
//  out and the power is calculated and put is power_sample.
//  Power_sample is accumulated and averaged to work out the average power
//  It also accumulated and used to generate the energy count.
//****************************************************   
V_sample=voltage_buffer_chan2[samples_read_index];
I_sample=current_buffer_chan2[samples_read_index];
power_sample=SIGNED_MUL(V_sample,I_sample); 
chan2_long_params[P_accum]+=power_sample;
++chan2_int_params[P_count];

power_sample>>=4;                           //need scaling down
//power_sample>>=7;
chan2_long_params[E_accum]+=power_sample;
if(chan2_long_params[E_accum]>=chan2_long_params[E_accum_threshold])
  {
  TAR_reading=TAR;
  chan2_int_params[ENERGY_PERIOD]=TAR_reading;
  chan2_int_params[ENERGY_PERIOD]-=chan2_int_params[LAST_TAR];
  chan2_int_params[LAST_TAR]=TAR_reading;
  
  chan2_long_params[E_accum]-=chan2_long_params[E_accum_threshold];
  ++chan2_long_params[E_accum_count];
  chan2_int_params[channel_status]|=E_TICK;
  P3OUT&=~CHAN2_PULSE;
  power_led_length_count=0;
  }
//******************************************************
//  A second power is calculated based on the current sample
//  phase lagged by 60.4 degrees or 11 samples
//  each sample = (50/3276.8)*360 =  5.4931640625 degree
//  delay by 11 samples or 60.4 degree
//  This phase lagged sample is multiplied by the none phase shifted 
//   voltage sample, the result power sample is used to calculate
//   the relative phase shift between the incoming current and voltage
//   signal. It is also used to self compensate for the CT lag
//  The resultant power is stored in a separate buffer and then averaged
//*******************************************************
i=samples_read_index;                                         
i-=11;
i&=0x3f;                                 //circular buffer adjust, buffer size must be
                                         //64!!!! 
I_sample=current_buffer_chan2[i];
chan2_long_params[PS_P_accum]+=SIGNED_MUL(V_sample,I_sample);
++chan2_int_params[PS_P_count];
//--------------------------------------------------------------------------
//  CHANNEL THREE
//--------------------------------------------------------------------------
  #if SIMULATED_INPUT 
//****************************************************  
//generate signal for use in testing, assume 50Hz and sampling freq of 3276.8
//  65.536 samples/cycle  
//****************************************************
                                        //use previously simulated results
  I_sample=simulated_current;
  V_sample=simulated_voltage;
  #else
//****************************************************
//  Read ADC results for Channel 1 voltage and current
//**************************************************** 
                                      //read current value 
  I_sample=ADC12MEM[7];
                                      //voltage is sampled twice both before and after current
                                      //so need to average to find out the value in the middle
  V_sample=(ADC12MEM[6]+ADC12MEM[8])>>1;                                 
  #endif  
//****************************************************
//  Take DC bias away from voltage and current samples
//  Take CT lag away from current sample
//  Store in Chan1 buffer
//**************************************************** 
                                        //get rid of the bias and calculate overall bias
  extract_dc_bias(&chan3_long_params[0],&chan3_int_params[0],&V_sample,&I_sample);   
                                        //get rid of CT delay for the current
  I_sample=FIR(chan3_int_params,I_sample);  
                                        //store into buffers                                  
  current_buffer_chan3[samples_write_index]=I_sample;                                        
  voltage_buffer_chan3[samples_write_index]=V_sample;
  
//if(samples_write_index>=SAMPLE_BUFFER_SIZE)
//  samples_write_index=0;                                        

//****************************************************
//  Now comes the reading part, both current and voltage is
//  out and the power is calculated and put is power_sample.
//  Power_sample is accumulated and averaged to work out the average power
//  It also accumulated and used to generate the energy count.
//****************************************************   
V_sample=voltage_buffer_chan3[samples_read_index];
I_sample=current_buffer_chan3[samples_read_index];
power_sample=SIGNED_MUL(V_sample,I_sample); 
chan3_long_params[P_accum]+=power_sample;
++chan3_int_params[P_count];

power_sample>>=4;                           //need scaling down
//power_sample>>=7;
chan3_long_params[E_accum]+=power_sample;
if(chan3_long_params[E_accum]>=chan3_long_params[E_accum_threshold])
  {
  TAR_reading=TAR;
  chan3_int_params[ENERGY_PERIOD]=TAR_reading;
  chan3_int_params[ENERGY_PERIOD]-=chan3_int_params[LAST_TAR];
  chan3_int_params[LAST_TAR]=TAR_reading;
  chan3_long_params[E_accum]-=chan3_long_params[E_accum_threshold];
  ++chan3_long_params[E_accum_count];
  chan3_int_params[channel_status]|=E_TICK;
  P3OUT&=~CHAN3_PULSE;
  power_led_length_count=0;
  }
//******************************************************
//  A second power is calculated based on the current sample
//  phase lagged by 60.4 degrees or 11 samples
//  each sample = (50/3276.8)*360 =  5.4931640625 degree
//  delay by 11 samples or 60.4 degree
//  This phase lagged sample is multiplied by the none phase shifted 
//   voltage sample, the result power sample is used to calculate
//   the relative phase shift between the incoming current and voltage
//   signal. It is also used to self compensate for the CT lag
//  The resultant power is stored in a separate buffer and then averaged
//*******************************************************
i=samples_read_index;                                         
i-=11;
i&=0x3f;                                 //circular buffer adjust, buffer size must be
                                         //64!!!! 
I_sample=current_buffer_chan3[i];
chan3_long_params[PS_P_accum]+=SIGNED_MUL(V_sample,I_sample);
++chan3_int_params[PS_P_count];
//--------------------------------------------------------------------------

//************************************************************
// If LED has been led then need to time it and switch it off
//************************************************************
if(++power_led_length_count>=1000)
  {
  power_led_length_count=0;
  P3OUT|=(CHAN1_PULSE+CHAN2_PULSE+CHAN3_PULSE);
  }    
 
//************************************************************
// Manage the circular buffer read and write pointers here
//  The buffer is 64 long
//************************************************************
++samples_read_index;
++samples_write_index;                                        
samples_write_index&=0x3f;
samples_read_index&=0x3f;

instant_temperature=ADC12MEM[9];
instant_VeREF_PLUS=ADC12MEM[10];
instant_VeREF_MINUS=ADC12MEM[11];

//***************** 
// Time Stampe
//P1OUT&=~BIT0;
//***************** 
}

extern int ticker,seconds,minutes,hours,days;

interrupt [BASICTIMER_VECTOR] void TWO_SECOND_TICKER(void)
{
ticker=1;
seconds+=2;
if(seconds>=60)
  {
  seconds=0;
  if(++minutes>=60)
    {
    minutes=0;
    if(++hours>=24)
      {
      hours=0;
      if(++days>=7)
        {
        days=0;
        }
      }
    }
  }
}