Sen. Edward M. Kennedy (D-Mass.) yesterday accused President Carter of "inaction, abdication, confusion and inconsistency" in dealing with the economy, and said if he were president he could "cut inflation by half within one year without inducing serious unemployment."

The claims came as part of a comprehensive economic policy paper released by Kennedy's campaign headquarters in Washington.

The main features of Kennedy's economic policy proposals, which have been made public before, include a six-month freeze of wages, prices, interest rates profits, dividends and rent, followed by mandatory controls over these areas "for as long as necessary to bring inflation down."

"The freeze and controls will not be sufficient to solve our underlying economic problems," he said in the paper. "Those problems by themselves -- and the inflation that is their symptom -- will yield only to a serious, sustained effort over the long term to increase investment and productivity, restore competition, recapture world markets and reduce our dependence upon foreign oil."

During a freeze, the paper said, raw agricultural commodities and imports would be exempt. A price board and a tripartite wage board, with labor, business and public representatives, "would develop and apply principles allowing the pass-through of cost increases and exceptions for cases of unfairness and hardship."

This policy would be based on requiring equal sacrifices from workers and business to offset the burden of rising raw material costs, such as for oil, the paper said.

Kennedy's statement said similar controls worked well during World War II and the Korean War, but less well when imposed in 1971 by President Nixon. In the Nixon years, controls did not work as well because they "were administered half-heartedly and inconsistently by persons ideologically opposed to such controls" and because "the Nixon fiscal and monetary strategy was expansionist," the paper said.

Kennedy criticized Carter for an economic policy that will lead to a 7.5 percent unemployment rate by the end of 1980, with a 10.4 percent inflation rate during the year, according to the administration's own forecast.

Kennedy, while critical of expansionist fiscal and monetary policies during the Nixon controls period, provided no specifics of what policy he would pursue this year to keep unemployment close to its present 6.2 percent level.

"A freeze and controls are likely to succeed today because of their strong psychological impact, because the president would personally intervene to insure effective and fair principles, governing wage and price increases, and because the American people are ready individually to accept some temporary economic sacrifice to restore real economic growth," the paper said.