pidcontrol.cpp

三容水箱的模糊控制设计

// PidControl.cpp : implementation file
//

#include "stdafx.h"
#include "Watertank.h"
#include "PidControl.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CPidControl

IMPLEMENT_DYNCREATE(CPidControl, CCmdTarget)

CPidControl::CPidControl()
{
	prev_u = 0.0;
	prev_e1 = prev_e2 = 0.0;
	//m_Ki = m_Kd = m_Kp = 1.0;
	kp = 0.1711;//0.000000001;
	ki = 0.014;	//0.0002;
	kd = 0.0079;// 2;	//0.00001;
}

CPidControl::~CPidControl()
{
}


BEGIN_MESSAGE_MAP(CPidControl, CCmdTarget)
	//{{AFX_MSG_MAP(CPidControl)
		// NOTE - the ClassWizard will add and remove mapping macros here.
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CPidControl message handlers

double CPidControl::CalcU( double input,  double reference)
{
   
	

   double output;
	


		double cur_err = reference- input;

	double delta_u = 0.0;
	double integ_bound = 10.0;

	if(cur_err < integ_bound && cur_err > -integ_bound)
		delta_u = kp * (cur_err - prev_e1) 
				+ ki * cur_err
				+ kd * (cur_err - 2*prev_e1 + prev_e2);
	else
		delta_u = kp * (cur_err - prev_e1) 
				+ kd * (cur_err - 2*prev_e1 + prev_e2);

	output = prev_u + delta_u;

	//shift variables
	prev_e2 = prev_e1;
	prev_e1 = cur_err;
	prev_u = output;
	//limit the minimum value
	if(output<0)
		output=0;
	if(output>3)
		output=3;
	return output;
}