President Carter is scheduled to announce today a new set of anti-inflation measures designed to show that the government is putting its own house in order as a prelude to prodding companies and unions to slow wage-price increases.

The package, still being revised late yesterday, is expected to include a proposal for 5.5 percent ceiling on federal raises, and new commitment by the administration to hold the budget deficit down.

Carter also is said to be considering "a strong statement" about the costly new farm bill - possibly even threatening a veto. Aides said he also will touch briefly on energy situation and the dollar.

Key administration officials cautioned yesterday that the package should not be regarded a "new" anti-inflation program, but rather a series of added measures to lay the groundwork for carrying out the plan announced in January.

As soon as the president delivers his address, the administration is expected to begin renewing its efforts to prod business and labor leaders to take step to slow inflation in the private sector of the economy.

Carter's January program - to persuade companies and unions to hold this year's wage and price increases below 1976-99 levels - never got off the ground. Today's speech that inflation may be speeding up.

The developments came as, separately G. William Miller, the new chairman of the Federal Reserve Board, urged Congress to roll back some of the recent Social Security tax increase to help reduce inflation.

However, administration officials said Carter was not likely to recommend any reduction in Social Security taxes in his speech today, despite urging by Miller and some other officials.

Indeed, the president sent a letter to key congressional leaders yesterday reiterating his opposition to any change in the Social Security tax increase legistated last year.

"The magnitude of the tax increase do not occur for several years," Carter said in his letter. He urged passage instead of his income tax cut and tax "reform" bill.

By far the major element in the president's new anti-inflation package is expected to be the proposed ceiling on federal pay increases . Without such a "cap," pay hikes for government white collars workers could average 6.75 percent.

Carter also is expected to urge governors and mayors to follow the federal government's example in holding down state and local government expenses. And he's expected to announce a streamlining of federal procurement policies.

The package includes:

A major commitment by the president to give a higher priority to the anti-inflation effort, both by vetoing excessively expensive legislation and by considering inflation problems in day-to-day policy decision.

An effort to open up more federal forest lands to private logging operations, to ease the lumber shortages that are pushing up housing costs. Carter also will announce other changed to eliminate government inflation-spurs.

A stepup in efforts by the Council on Wage and Price Stability to begin talks with business and labor leaders on what the private sector can do to help slow inflation.

Carter is expected to attempt to relate the anti-inflation to the energy situation and the recent decline on the dollar. But aides said they expect no major new moves in either of those areas.

The package is response to mounting criticism in the past few weeks that the administration has not been doing enough to combat inflation, despite the program the president announced in January.

Carter has been assailed dfor several major policy decision last year and this which economists say have tended to exacerbate the rate for higher Social Security taxes and import quotas.

Meanwhile, the inflation rate has been speeding up in the past few months, with prices rising at more than a 7 percent rate in the first quarter of this year, rather than the 6 th 6 1/2 percent pace Carter had predicted.

The measures Carter will announce today aren't expected to result in any dramatic slowdown in the current inflation rate, but officials assert they will be a visible start.

The president's letter opposing any rollback in the Social Security tax increases marked his strongest statement yet on that controversial issue. Congress seems likely to trim payroll on grounds that it would reduce business costs and presumably avert large price hikes later. "Anything we could do . . . would be helpful in the fight against inflation," he said.

However, the Fed chairman opposes a move being discussed in Congress to use income tax revenue to help finance Social Security of Medicare benefits. He said any rollback should be accompanied by an "adjustment of benefits" or some other source of funding.