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what is the difference between Feedback controller and Feed
forward controller. and when it is to be used.
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Answer Posted / vaishnavi
In the case of feedfwd controller we need to know the complete mathematical model and all the load variables acting on the process which is not possible and this takes anticipatory action b4 the disturbances can affect the process.
weras feedback control takes corrective action by measuring the error once the process is affected by load variables.and in this case we need not know the load var acting on the sys and no need for mathematical model.
hence usually feedfwd cant be used alone and is used in combination with feedback.
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