Ronald Reagan took his victory lap around Washington to the Supreme Court and for a return visit to Capitol Hill yesterday, avoiding comment on potentially controversial issues while pledging cooperation with all.

The president-elect also received visits from three senators with contrasting reasons to pay their respects at the government where Reagan is holding court across Pennsylvania Avenue from the White House.

Sens. John G. Tower (R-Tex.), who wants to be Reagan's secretary of defense, Edward M. Kennedy (D-Mass.), who had never met Reagan and wanted to make a peace overture, and Richard Schweiker (R-Pa.), who underwent a sudden conversion in 1976 to become Reagan's running mate and reportedly now seeks a post in the new administration, made their way to private audiences with Reagan.

It was a second day of successful message-sending by Reagan, who has excited the Capitol not so much with deeds as with symbols on the eve of his presidency.

Reagan began with a briefing from CIA Director Stansfield Turner and then rode to the elegant Senate Caucus Room for a luncheon with about 200 Republicans from both houses of Congress.

"We have never seen the party so united and enthused. We have a mandate now," Reagan told them.

"The people of this country have told us they want something different. They want a change. They want an America they can be proud of, an America that serves them and doesn't interfere with every facet of their lives . . ." Reagan broke off from his rhetoric, joking, "If I keep on with this, I'll be making a campaign speech."

Reagan, who has circled around the White House while making his warmly received rounds this week, will meet President Carter in the White House today.

The president-elect has made it clear that he will bring back to Washington the traditional politics of ego-stroking and flattery through the appearance, if not the reality, of seeking advice from a wide circle and he poked fun yesterday at one of Carter's pettier attempts to change the practice of politics here by pinching pennies.

"This time when you're invited over to the White House for breakfast," he told the congressional luncheon, "I won't send you a bill."

Reagan rode from his luncheon to the Supreme Court where Chief Justice Warren Burger received him privately and then escorted Reagan and Vice President-elect George Bush into the Conference Room where the justices make their decisions to pose for photographers.

Burger, whose dislike of the media is profound and well-known, remarked to Reagan that it was the first time he had permitted cameras in the Conference Room. He looked over at the crowd of journalists with an evident lack of enthusiasm and said: "Quite a lot of them, aren't there."

Reagan and Bush each signed the court's guest book and Reagan remarked it was the first time he had noticed that Bush is left-handed.

According to court historians, Reagan's visit revived an old tradition. Presidents since Franklin D. Roosevelt have visited the court at one time or another, usually for the swearing in of a new member -- except for Carter, who also has been the first since Roosevelt not to name a justice -- but presidents-elect have not come to the court since the 19th century.

Burger escorted Reagan, Bush and Edwin Meese III and James A. Baker III, who will be the top two White House aides, into the justices' dining room to meet the other members of the court. All were present except Justice William Rehnquist, who had a speaking engagement at Vanderbilt University Law School.

Coffee, tea or white wine were the choices, Reagan took a glass of wine.

Tower and Schweiker refused to talk to reporters as they left their meetengs with Reagan. Kennedy, however, answered questions.

He said he requested the meeting through Reagan's close associate Sen. Paul Laxalt (R-Nev.) because he had never met Reagan and wanted to express his willingness to cooperate.

Kennedy and Reagan each announced for the presidency at about the same time last year and now Reagan is president-elect and Kennedy is about to become the ranking minority member on the Judiciary Committee, Kennedy remarked wryly. He said, sounding more like a Republican than he did earlier in the year, the election showed the people want cooperation and support for the new president. "It is in that spirit that I came here today to indicate [my support]."

Reagan's transition office announced several new personnel appointments, including Melvin L. Bradley, who will be a special adviser to the director of the office of presidential personnel and will be responsible for recruiting minorities to the Reagan administration.

Bradley said minority Democrats as well as Republicans would be considered and that he expected the Reagan administration to break new ground by appointing minorites to posts other than those which he said have traditionally gone to blacks and Hispanics.

The government-in-waiting also named seven more people to head transition teams at specific agencies. The new team leaders are:

National Transporation Safety Board: Henry Zuniga, one of the leaders of the Hispanic branch of the Reagan-Bush campaign.He is a federal employe, working in the Dallas office of the Office of Minority Business Enterprise.

Export-Import Bank: William W. Geimer, an international trade lawyer in Washington. He was assistant secretary of state for trade under President Ford.

Federal Maritime Commission: Donald L. Ivers, a New Mexico native who has been legal counsel to the Republican National Committee here.

Interstate Commerce Commission: Frederic N. Andre, a financial consultant in Paoli, Ind., and former Indiana commissioner of motor vehicles.

Advisory Commission on Intergovernmental Relations: Freda J. Poundstone, an active Republican from Denver.

National Science Foundation: James Chipman Fletcher, an engineer who directs the energy resources program at the University of Pittsburgh. He was administrator of NASA under Presidents Nixon and Ford.

General Services Administration: Harvey Kapnick, of Winnetka, Ill., former chairman of Arthur Andersen & Co., the big accounting firm.