Assuming the Ideal form: 
The PID controller in MATLAB takes the practical form 
, where 
represents the time constant of the derivative filter. The Simulink PID controller block has an equivalent practical form but expressed in N, instead of 
where 
. When the value of 
is very small (or N is very large), the practical PID form closely approximates the ideal PID form.
, where represents the time constant of the derivative filter. The Simulink PID controller block has an equivalent practical form but expressed in N, instead of where . When the value of is very small (or N is very large), the practical PID form closely approximates the ideal PID form.See also:
