python实现PID算法及测试的例子-创新互联

PID算法实现

import time

class PID:
  def __init__(self, P=0.2, I=0.0, D=0.0):
    self.Kp = P
    self.Ki = I
    self.Kd = D
    self.sample_time = 0.00
    self.current_time = time.time()
    self.last_time = self.current_time
    self.clear()
  def clear(self):
    self.SetPoint = 0.0
    self.PTerm = 0.0
    self.ITerm = 0.0
    self.DTerm = 0.0
    self.last_error = 0.0
    self.int_error = 0.0
    self.windup_guard = 20.0
    self.output = 0.0
  def update(self, feedback_value):
    error = self.SetPoint - feedback_value
    self.current_time = time.time()
    delta_time = self.current_time - self.last_time
    delta_error = error - self.last_error
    if (delta_time >= self.sample_time):
      self.PTerm = self.Kp * error#比例
      self.ITerm += error * delta_time#积分
      if (self.ITerm < -self.windup_guard):
        self.ITerm = -self.windup_guard
      elif (self.ITerm > self.windup_guard):
        self.ITerm = self.windup_guard
      self.DTerm = 0.0
      if delta_time > 0:
        self.DTerm = delta_error / delta_time
      self.last_time = self.current_time
      self.last_error = error
      self.output = self.PTerm + (self.Ki * self.ITerm) + (self.Kd * self.DTerm)
  def setKp(self, proportional_gain):
    self.Kp = proportional_gain
  def setKi(self, integral_gain):
    self.Ki = integral_gain
  def setKd(self, derivative_gain):
    self.Kd = derivative_gain
  def setWindup(self, windup):
    self.windup_guard = windup
  def setSampleTime(self, sample_time):
    self.sample_time = sample_time