olemus
ISO/TR 11065:
võimsusvõimendust ja tagasisidet sisaldav automaatjuhtimissüsteem, mis viib väljundmuutuja väärtuse tugevasse vastavusse sisendsuuruse väärtusega
= an automatic control system incorporating power amplification and feedback that causes the value of an output variable to correspond closely to the value of an input quantity

ülevaateid
https://www.elprocus.com/difference-between-open-loop-closed-loop-control-system/
https://electronicscoach.com/closed-loop-control-system.html
http://www.electronics-tutorials.ws/systems/closed-loop-system.html
http://www.powershow.com/view/1217ff-NzlhM/ClosedLoop_System_powerpoint_ppt_presentation
https://sites.chemengr.ucsb.edu/~ceweb/faculty/seborg/teaching/SEM_2_slides/Chapter%2011%20%2811-23-04%29.pdf
http://www-control.eng.cam.ac.uk/gv/p6/Handout5.pdf