I have a question, why is this possible? What I've been told so far is that in real life you cannot implement a PD since you have a zero without a pole, and a system in order to be physicially possible the numer of poles needs to be greater than the number of zeros. Also what I've always been told is that in order to be able to do a PD in real life, you must add a pole, leaving you with the following expression: Gpd(s)=(Kc·(s+z))/(s+p) Could you please clarify my question? Thank you in advanced :)
Thanks for your message. Indeed, a practical PD controller requires a pole to reduce the high-frequency noise. The location of this pole will affect the PD action, so ther depends on the system requirements.
I have a question, why is this possible? What I've been told so far is that in real life you cannot implement a PD since you have a zero without a pole, and a system in order to be physicially possible the numer of poles needs to be greater than the number of zeros. Also what I've always been told is that in order to be able to do a PD in real life, you must add a pole, leaving you with the following expression:
Gpd(s)=(Kc·(s+z))/(s+p)
Could you please clarify my question? Thank you in advanced :)
Thanks for your message. Indeed, a practical PD controller requires a pole to reduce the high-frequency noise. The location of this pole will affect the PD action, so ther depends on the system requirements.