Right here, we will introduce an increase possibilities approach according to the regularity response of your program
From Eq. (dos.28) , it could be viewed the current-control characteristic depends on the fresh new show of one’s newest control, which can be dependent on the P and that i growth selected to the PI controller.
2.6.step one Proportional–Integral Current Control
A recently available handle system that has had a PI operator was revealed when you look at the Fig. 2.thirty two . Here, think that the new feedforward control makes up the trunk-EMF of the DC motor really well.
in which T p i ( = K p c / K i c ) ‘s the inbuilt date lingering of one’s PI newest controller and you will K we c is the inbuilt acquire.
There are PI obtain tuning statutes including the greatest Ziegler–Nichols strategy. Right here, we’ll adopt the strategy known as pole-no termination approach. With the rod-no cancellation, we can eliminate the current control characteristic of your own DC motor alone therefore the PI operator may dictate the fresh new show from the modern handle.
When your zero ( ? K we c / K p c ) of your own PI operator was designed to terminate the brand new rod ( ? Roentgen a great / L a good ) of your own DC motor by rod-zero cancellation approach, i.e.
Fig. dos.33 suggests the newest bode spot of one’s discover-circle volume impulse regarding Grams c o ( s ) . Brand new stage try ?90° from the get get across-more than frequency ? c c where in actuality the magnitude | G c o ( j ? ) | = 0 dB . For this reason the new obtain margin try self-confident plus the system would be steady. Including, in this situation, the transfer reason for Eq. (2.32) becomes the machine of kind of=step one and you can, hence, we could predict the new steady-state error to-be no since
Brand new get cross-more than frequency ? c c of your discover-circle regularity answer is comparable to the brand new obtain slash-out of frequency of one’s romantic-cycle volume reaction, which means brand new data transfer of one’s current-control program. Let us see the data transfer of the current control system.
Its regularity response is found during the Fig. 2.34 . We are able to see that the latest bandwidth associated with the system is considering once the ? c c by allowing | G c c ( j ? ) | comparable to step one / dos (=?step 3 dB) because
In this way, should your no of PI operator is made to cancel brand new rod of your own program, the present day handle method is shown simply due to the fact an initial-purchase system that have a cut right out-out-of volume ? c c , that is secure. In such a case, there won’t be any overshoot regarding effect and the time needed for the response to get to the last value might be regarding four times the amount of time lingering of the program.
Based on the cause considering over, the brand new proportional and you may built-in development of one’s current controller had a need to get to the expected bandwidth are going to be computed the following.
When your expected control https://datingranking.net/es/solteros-locales/ bandwidth try ? c c , then the proportional obtain K p c exists from Eq. (2.34) in addition to integrated acquire K i c can be found away from Eq. (dos.31) because the
It is very important observe that the earnings of your control depend on the latest engine variables L an excellent and you may Roentgen a . And the get opinions to get the exact same current-control efficiency ple, a system having a large worth of winding inductance, whose most recent is difficult to change, needs a much bigger proportional obtain to get an equal bandwidth of the modern control than by using a little value of wandering inductance, whoever latest is easy to change. For this reason, precise details about the fresh new engine variables is important to achieve the necessary current control show.