code on the first

 
100//# define MAX_DUTY output biggest duty ratio 

PID sPID; 
The static pPID SPTR; 

Void IncPIDInit (void) 
{
SPTR=& amp; SPID; 
SPTR - & gt; SetSpeed=1000;//value 

SPTR - & gt; The LastError=0 u;//2 times before error values 
SPTR - & gt; PrevError=0 u;//1 time before error values 

SPTR - & gt; Proportion f=0.41;//ratio 
SPTR - & gt; Integral=0.25 f;//integral 
SPTR - & gt; Derivative f=0.12;//differential 

SPTR - & gt; IError=0;//the current error 
SPTR - & gt; IIncpid=0;//increment error 

SPTR - & gt; Uk=0;//output return value 
} 

Int IncPIDCalc (int tag_speed) 
{
Int duty_pwm; 

//the current velocity error 
SPTR - & gt; IError=SPTR - & gt; SetSpeed - currentSpeed; 

//increment error 
SPTR - & gt; IIncpid=SPTR - & gt; Proportion * SPTR - & gt; IError SPTR - & gt; Integral * SPTR - & gt; LastError 
+ SPTR - & gt; Derivative * SPTR - & gt; PrevError; 

//store the error for the next calculation 
SPTR - & gt; PrevError=SPTR - & gt; IError; 
SPTR - & gt; LastError=SPTR - & gt; LastError; 

SPTR - & gt; Uk +=SPTR - & gt; IIncpid; 

Duty_pwm=SPTR - & gt; The Uk * 0.2 f; 

//output value limiter 
If (duty_pwm & gt;=MAX_DUTY) 
{
Duty_pwm=MAX_DUTY; 
} 
Else if (duty_pwm & lt;=0 u) 
{
Duty_pwm=0; 
} 

Return duty_pwm; 
} 

Tuning PID for the first time, have a few questions to ask

1. Using the incremental PID, increment is obtained by the current and target speed conversion error, SPTR - & gt; IIncpid how to get PWM duty ratio conversion, I get a light 100% duty cycle speed to 500 RPM, is that can conversion by system 0.2

2. SPTR - & gt; IIncpid incremental error is it need to adjust the speed deviation and the speed of the next need rectification

3. The coefficient KP ki kd how to adjust, through simulation or themselves one by one the speed curve blind adjustable

CodePudding user response:

if the motor no-load and load cases, whether the coefficient is also need to separate into two groups

CodePudding user response:

SPTR - & gt; IIncpid=SPTR - & gt; Proportion * SPTR - & gt; IError - SPTR - & gt; Integral * SPTR - & gt; LastError + SPTR - & gt; Derivative * SPTR - & gt; PrevError ;

The red part is not correct,

Ei=target - current value;
Kp + Ki * * ei PID=Sum (ei) + Kd (ei - ei1);//ei current error values, ei1 last error values