Democrats loyal to President Carter made the key decisions yesterday on the draft of a party platform lauding the president and largely ignoring the policy proposals of his principal Democratic rival, Sen. Edward M. Kennedy (D-Mass.).

The draft platform will contradict in several major ways the 1976 party statement on which Carter first ran for the presidency and will include only vague references to some of the traditional liberal Democratic sacred cows that Kennedy has sought to reenshrine during his campaign.

The drafting subcommittee voted to reject planks calling for immediate wage and price controls, an immediate $12 billion anti-recession program and restraints on imports of foreign cars and steel, among others proposed by the Kennedy supporters on the panel.

Any thought that the platform-writing process would provide an opportunity for reconciliation between the Carter and Kennedy camps evaporated when it became clear that neither side was really interested in bending its substantive positions to satisfy the other.

The Carter loyalists involved in the process took the position that since their man had won the overwhelming majority of convention delegates in the state primaries and caucauses, they should write the main points of the platform. The Kennedy camp -- consistent with the current position on its candidate -- refused to acknowledge a Carter victory, and refused to alter any of the important positions Kennedy has taken this year.

Instead, the Kennedy loyalists on the platform drafting committee offered those positions as planks in the platform, and the pro-Carter majority consistently beat them back.

At that stage, the Kennedy camp did not try to see if the Carter group could be pushed toward more liberal stances on the key economic and energy issues, but instead insisted on offering Kennedy's proposals intact. The Carter campaign's willingness to compromise could be tested again either when the full platform committee meets here this weekend, or in August at the Democratic National Convention.

The principal issues on which pro-Kennedy members of the drafting committee took their stand yesterday were five economic proposals: support for the immediate $12 billion antirecession program; support for immediate wage and price controls; a pledge not to fight inflation with any policy that would increase unemployment; support for specific Kennedy ideas for a "reindustrialization corporation," a new U.S. trade agency and a new international trade organization, and a pledge to seek voluntary restraints on foreign (especially Japanese) exports of steel, and autos to the United States, without abandoning the posibility of imposing import quotas or higher tariffs.

All these were embodied in proposed platform planks, and all were rejected in the drafting committee yesterday by 7-to-5 or 8-to-5 votes. The committee consists of nine pro-Carter members, five pro-Kennedy members and one neutral, but all the Carter members were not in the meeting room yesterday.

Peter Edelman, Kennedy's chief spokesman on issues, told reporters yesterday that these economic issues were "absolutely the most fundamental in the campaign," acknowledging that no others were of equal interest to Kennedy. But he said the Kennedy camp would continue to offer alternative planks on other topics as the drafting subcommittee continued its work. The committee will continue its deliberations today, and a final draft is expected Saturday.

Kennedy aides complained, sometimes bitterly, sometimes bemusedly, that the subcommittee majority was prepared to abandon not only traditional Democratic positions, but aslo the 1976 Democratic platform on which Carter was elected president.

Carter supporters, beginning with chief domestic aide Stuart Eizenstat, offered forceful defenses of their positions, arguing that Carter was dealing with realities as best he could. For example, Eizenstat insisted yesterday that the new recession was not the fault of Carter policies, but was caused by the loss of "$90 billion in productive resources that have been drained out of the economy to pay off imported oil.

As it is emerging, the 1980 platform will indeed depart from the 1976 document. For example, the 1976 platform lambasted Republican energy policies as "illusions," not least for their reliance on the free-market approach to energy prices that the Carter administration has since embraced. In fact, the 1976 platform's energy plank is very close to Kennedy's energy proposals this year, but none of them will be included in the 1980 version.

The 1980 platform will not include a series of promises made in 1976 for full funding of domestic social programs, will be weaker in its pledges to causes favored by organized labor, and will offer less ambitious economic plans.

Whether any of these departures will provoke a fight in the full platform committee or at the convention remains problematical. At the moment the Carter camp seems to be fully in control. "The majority . . . is in the position to dictate whatever it wants in the platform," Kennedy aide Edelman said yesterday.

Any hope of overturning that majority must depend -- like the remaining hopes for Kennedy's candidacy -- on unforseen developments that might shake the loyalty of Carter delegates to the national convention in August.

In the best Democratic Party tradition, the two factions in this platform-drafting squabble made some efforts to behave politely to one another, but quickly fell to squabbling. Sharp accusations have been exchanged all week, and according to participants in the closed drafting sessions, they have often been heated.

At one point Wednesday night, sources said, a Kennedy spokesman was reading quotations from Carter's past statements on energy that argued against the energy policies the president has now adopted. Sen. Daniel Patrick Moynihan (D-N.Y.), the one "independent" on the subcommittee, interrupted this process to say that no one should be held accountable for statements about energy made more that five months ago.

Gov. Richard Riley of South Carolina, hand-picked by the Carter campaign, had chaired the drafting subcommittee.