# Problem with PID controller in DC\_current and FOC\_current

**URL:** https://community.simplefoc.com/t/problem-with-pid-controller-in-dc-current-and-foc-current/6577
**Category:** developement
**Created:** [January 14, 2025, 11:06am UTC](https://community.simplefoc.com/t/problem-with-pid-controller-in-dc-current-and-foc-current/6577 "2025-01-14T11:06:33Z")
**Posts on this page:** 1
**Page:** 1

<div class="post-metadata">

### Author: ![chuategiaitich](https://community.simplefoc.com/user_avatar/community.simplefoc.com/chuategiaitich/32/7764_2.png) [@chuategiaitich](https://community.simplefoc.com/u/chuategiaitich)
#### Post date: [January 14, 2025, 11:06am UTC](https://community.simplefoc.com/t/problem-with-pid-controller-in-dc-current-and-foc-current/6577/1 "2025-01-14T11:06:33Z")

</div>

I am trying to control **GM3506** motor with **SimpleFOC v2.0.4** on **arduino mega**.

In **TorqueControlType::dc\_current** , I am calibrating the PI for q axis but the process is not smooth. The motor keeps shaking around the target position. But when I change to **TorqueControlType::voltage** with PID for velocity and angle, everything is back to normal.

I am not sure which step I am doing wrong or the process I am calibrating the PID is not correct. Hope to receive answers from experts

Here is my code and the pid parameters I tried  
[P=0,5]

 ![p0,5](https://community.simplefoc.com/uploads/default/original/2X/3/3a62b077ce916201522715a06d74a93940dc51d9.jpeg)  
[P=0,9]  
 ![p0,9](https://community.simplefoc.com/uploads/default/original/2X/e/e69e430033ab4e4bc6c162de09bf16f39c673224.jpeg)  
[P=0,5 ; I=20]  
 ![p0,5i20](https://community.simplefoc.com/uploads/default/original/2X/4/40d33f18808ef29b6b852fcdf73282d3f3e59c9c.jpeg)  
[P=0,5 ; I=50]  
 ![p0,5i50](https://community.simplefoc.com/uploads/default/original/2X/2/2a5e344646f2ee2a17cc9b2c7c7cf29e030aa686.jpeg)

Code:

```auto
#include <SimpleFOC.h>

MagneticSensorSPI sensor = MagneticSensorSPI(AS5147_SPI, 53);
BLDCMotor motor = BLDCMotor(11);
BLDCDriver3PWM driver = BLDCDriver3PWM(9, 5, 6, 8);
InlineCurrentSense current_sense = InlineCurrentSense(0.01f, 50.0f, 54, 56);
float target_angle = 0;
bool is_button_Press=false;

void calibrations()
{
  if(Serial.available() > 0)
  {
    char inCommand=Serial.read();
    if(inCommand=='t')
    {
      target_angle=Serial.parseFloat();
    }
    if(inCommand=='p')
    {
      motor.PID_current_q.P=Serial.parseFloat();
    }
    if(inCommand=='i')
    {
      motor.PID_current_q.I=Serial.parseFloat();
    }
    if(inCommand=='f')
    {
      motor.LPF_current_q.Tf=Serial.parseFloat();
    }
    if(inCommand=='c')
    {
      motor.disable();
    }
  }
}

void setup() {
 
  Serial.begin(115200);
  pinMode(22, INPUT_PULLUP);

  sensor.init();
  motor.linkSensor(&sensor);

  current_sense.gain_b *= -1;
  current_sense.init();

  current_sense.linkDriver(&driver);
  motor.linkCurrentSense(&current_sense);

  driver.voltage_power_supply = 12;
  driver.init();

  motor.linkDriver(&driver);

  motor.foc_modulation = FOCModulationType::SpaceVectorPWM;
  // motor.torque_controller = TorqueControlType::foc_current;
  motor.torque_controller = TorqueControlType::dc_current;
  motor.controller = MotionControlType::angle;

  motor.PID_velocity.P = 0.07;
  motor.PID_velocity.I = 5;
  motor.PID_velocity.D = 0.001;
  motor.LPF_velocity.Tf = 0.01;

  motor.P_angle.P = 6;
  motor.LPF_angle.Tf = 0.01;

  // motor.PID_current_d.P = 0;
  // motor.PID_current_d.I = 0;
  // motor.PID_current_d.D = 0;
  // motor.PID_current_d.limit = 1; 
  // motor.LPF_current_d.Tf = 0.01;

  motor.PID_current_q.P = 0;
  motor.PID_current_q.I = 0;
  motor.PID_current_q.D = 0;
  motor.PID_current_q.limit = 1; 
  motor.LPF_current_q.Tf = 0.005; 

  motor.voltage_limit = 2;
  motor.velocity_limit = 5;

  motor.sensor_direction=Direction::CW;
  motor.sensor_offset=0.2;
  motor.zero_electric_angle=3.4798;

  motor.init();
  motor.initFOC();

  _delay(1000);
}

void loop()
{
  if(digitalRead(22)==0 && !is_button_Press)
  {
    motor.disable();
    Serial.println("stop");
  }

  calibrations();

  motor.loopFOC();
  motor.move(target_angle);

  // plot 
  Serial.print(">Current sense:");Serial.println(current_sense.getDCCurrent());
  Serial.print(">Angle_error:");Serial.println(target_angle-(target_angle-sensor.getAngle()));
  Serial.print(">P:");Serial.println(motor.PID_current_q.P);
  Serial.print(">I:");Serial.println(motor.PID_current_q.I);
  //
}

```