• What I am trying to do : Run 3-phase Induction motor using Direct Torque Control method.
• 
• What I am sensing: 3-phase stator currents through current sensor board and speed through speed encoder.
• 
  • MCU: TI C2000 F29069M
  • Level Shifter: 2.5 shift, 0.5 gain
  • Current sensor: 0.1 gain
  • The issue: Significant jumps in current retrieved and seen through DAC, even if the voltage supply is not given.
• Waveforms shown below:
  1. Yellow : Phase A current retrieved and seen through DAC
  2. Green : Phase B current in DAC
  3. Blue : Phase C current in DAC
  4. Pink : Phase A actual current sensed by current probe
• Fig 1. Only shift seen in DAC as the code is not yet turned on.
• 
•                                                                                                       Fig 1. Only the shift of level shifter seen in DAc as code not yet started. Fig 2 Below shown when the inverter switching is started, these jumps are seen in the phase currents 1. 2. & 3 waveforms .
• 

                                                                                                                                                           Fig .2 Jumps in current even though supply is off   

• Fig 3. When supply is given, the first three waves (phase A, B, C currents) are not sine wave as they should come as the 4th waveform (pink). 4th waveform is the phase A current through current probe.

• Another issue I am facing is that the speed encoder is not giving some constant value of speed while running the motor. It is varying a lot by +-30 to 40 rpm which is affecting the speed control PI loop as well. Is it because of the encoder fault or in my code some problem is there?

DTC_main_code.txt

• DTC_code_in_the_making_running.rar
• https://drive.google.com/file/d/1hhtWEjeKVyfbSTSMe...
• https://drive.google.com/file/d/1Y5nbDf3eZ-TORg3oS...