Right here, we are going to introduce an increase choices method based on the regularity impulse of your system
Regarding Eq. (dos.28) , it can be viewed your current control feature hinges on the latest overall performance of the current control, that’s influenced by the latest P and i also progress picked on the PI control.
dos.6.step one Proportional–Integral Latest Control
A current manage system with which has a PI controller is actually shown into the Fig. 2.32 . Here, assume that the newest feedforward manage makes up the back-EMF of one’s DC system well.
where T p i ( = K p c / K we c ) ‘s the integrated time constant of your own PI newest operator and K we c is the integrated gain.
You will find some PI get tuning guidelines for instance the popular Ziegler–Nichols method. Right here, we’ll embrace the strategy called the rod-zero cancellation method. Utilising the rod-zero termination, we can take away the current control characteristic of DC system by itself and so the PI control may influence the new results from the present day control.
Should your zero ( ? K i c / K p c ) of your PI control was created to cancel brand new pole ( ? R a / L a beneficial ) of one’s DC motor of the pole-zero termination strategy, i.elizabeth.
Fig. 2.33 reveals the brand new bode patch of your own unlock-circle volume response out-of Grams c o ( s ) . The latest phase was ?90° from the acquire mix-over regularity ? c c in which the magnitude | G c o ( j ? ) | = 0 dB . Hence the fresh new obtain margin try positive in addition to program might possibly be secure. Including, in cases like this, the new transfer aim of Eq. (2.32) gets the computer regarding connessione incontri cristiani types of=step one and you can, thus, we are able to predict the fresh steady-condition error are zero due to the fact
The newest obtain mix-more than regularity ? c c of discover-loop frequency answer is equal to the new obtain slashed-of frequency of your personal-cycle volume effect, hence suggests the fresh new data transfer of current-control system. Let’s see the data transfer associated with current control system.
Their volume answer is revealed inside the Fig. dos.34 . We can observe that the newest bandwidth of method is provided because ? c c by allowing | G c c ( j ? ) | equal to 1 / 2 (=?step 3 dB) once the
Similar to this, when your zero of PI control is made to terminate the brand new pole of system, the present day manage experience indicated just as an initial-order program that have a cut fully out-away from volume ? c c , that’s secure. In this case, there will be no overshoot about impulse additionally the time required for the answer to achieve the latest really worth was on 4 times the amount of time lingering of one’s system.
Based on the reasons provided a lot more than, the fresh new proportional and you can integrated development of most recent operator had a need to reach the necessary data transfer will be determined the following.
If the required manage bandwidth is actually ? c c , then proportional acquire K p c is present off Eq. (dos.34) in addition to built-in obtain K we c can be found out of Eq. (2.31) because the
You will need to remember that the gains of controller rely on new system parameters L a good and you will Roentgen an excellent . While the get beliefs to have the same current control show ple, a motor which have an enormous worth of winding inductance, whoever most recent is tough to improve, requires a much bigger proportional obtain locate the same data transfer regarding the current manage than just by using a little worth of wandering inductance, whoever most recent is straightforward adjust. Therefore, right facts about this new system details is very important to get the requisite current-control performance.