The colloquial compound control freak designates a person who demonstrates a need to exercise tight control over his or her surroundings, behaviour or appearance, especially by assuming command of any situation or exerting authority over others.

This compound occurred, for example, in Control freak Meyer now ‘knows nothing’, by Paul Newberry, AP sports columnist, published in The Flint Journal (Flint, Michigan, USA) of Sunday 5^th August 2018:

College coaches are notorious control freaks.
From making sure every minute of practice is accounted for to fretting over what players are putting in their bodies at the dining hall, no detail is too small for a coach’s prying eyes.
They have to know everything.

More generally, the noun freak is used as the second element in colloquial compounds designating a person who is obsessed with the activity, interest or thing denoted by the first element.

This usage of the noun freak originated in American English. An early compound, kodak freak, occurred in the following from The Daily Morning Alaskan (Skagway, Alaska, USA) of Saturday 1^st March 1902:

A SNOW MAN
Is an International Work of Art at the Summit.

Customs Inspector G. A. Waggoner, came down from his station at White Pass on last night’s train to take a short respite from his monotonous routine on the summit of the mountain. The few people who have passed the winter at the summit, have made the best of their dreary surroundings and have spent the long winter evenings at reading, whist and conversation. One of the enterprises of the little international community, was the shaping of a piece of snow statuary in the figure of a man 24 feet high. It is a joint art creation of everybody in the community, and great care and much labor has been expended on its make up. As the statue was reared the fashioned snow was sprinkled with water, so that it is virtually an ice creation and will stand guard at his post till the chinooks melt him away. The snow statue has been snapshoted by nearly every kodak freak who has passed either up or down the line, and its picture may soon be seen in Case & Draper’s window.

The earliest occurrence of the compound control freak that I have found is from Utah County Communists, by Steve Holbrook, published in The Daily Utah Chronicle (Salt Lake City, Utah, USA) of Thursday 16^th November 1967:

Most young leftists in Utah and elsewhere across the nation can spot these people and their organizations right away. First of all the commies are control freaks and can’t stand disorderly organization. The commies have never been too happy with the streak of bohemianism that runs through much of the new left, so the guy who tells you to cut your hair and shave may just as easily be a commie as a capitalist.

The compound power freak is rather similar in meaning to control freak. The earliest occurrence of power freak that I have found is from the Sunday Light (San Antonio, Texas, USA) of Sunday 14^th July 1968:

THE NORTHWEST
‘Old Politics’ Days Over
By SHELBY SCATES

SEATTLE—Whatever happens to the balance of it, this 1968 presidential campaign is the last hurrah for the “old politics,” say Northwest supporters of Sen. Eugene McCarthy and the late Robert Kennedy.
“The handwriting is on the wall for Democrats right now,” says Blaine Whipple, Portland, a McCarthy campaign coordinator in the Northwest. […]
[…]
“If they have to choose between Humphrey and Richard Nixon, most of them will vote for Humphrey but very few will actively work for him,” said Whipple.
[…]
“Humphrey is just another power freak,” said one longhaired McCarthy delegate to a Democratic district caucus in Seattle. “Bump the Hump, I say.”
They are not cemented to the Democratic party, these students, middleclass professionals, Negro militants and academic intellectuals. They were attracted by the styles of McCarthy and Kennedy, repelled by the Johnson administration.