The separatist Parti Quebecois today shelved independence for Quebec Province as a plausible political goal, bringing down the curtain on 17 years of insistent demands that French Canada become a sovereign nation.

The new direction came at a special party convention today where 61 percent of the delegates approved a proposal by Quebec Premier Rene Levesque to change the party platform, deleting a provision that would make independence for Quebec the central issue of the next provincial election. The vote took place after about 200 of Levesque's opponents had walked out of the convention.

In an unusually subdued speech at the session's end, Levesque called the confrontation "beneficial surgery," but he also invited the dissidents to return to the fold. He denied that he was minimizing the sovereignty issue solely out of a wish to retain power in the next provincial election.

The change came in the face of slumping popular support for the creation of a separate French nation among the 6 million Quebecois. The issue of separatism and equality for French speakers within the nation of 25 million has roiled Canadian politics for most of the past 20 years.

Earlier in the day, Levesque handily turned back a series of challenges from hard-line separatists who accuse him of abandoning the cause of independence. Levesque, 62, founded the Parti Quebecois in 1968 and has won three provincial elections since 1976, largely because of his appeal to deeply rooted separatist sentiments in Quebec, Canada's most populous province.

However, self-styled "orthodox" party hard-liners have been increasingly unhappy with what they view as Levesque's centrist goals that favor Quebec continuing as part of Canada. In the past two months, seven hard-liners resigned in protest from his provincial Cabinet of 30 ministers. Levesque called the special party session to deal with this challenge and, some believe, to rid the party of the hard-liners by forcing a walkout.

The party's appeal has declined in recent years. Membership now stands at 113,000, down from 300,000 just three years ago. Separatists' zeal has diminished in the face of the severe Canadian recession, which began in the late 1970s and from which the country has not yet recovered. In addition, the Parti Quebecois suffered a stunning reversal in 1980, losing a referendum on sovereignty. The hard-liners blame much of the decline on Levesque, who has been in uncertain health recently.

But the 62-year-old Levesque led his forces to a series of easy victories over the hard-liners today. About 200 of his opponents walked out after losing several procedural votes by lopsided margins. They made a colorful scene, swarming out of the Palais de Congres under a hand-painted banner that read, "Quebec for Quebecois." Hundreds of delegates applauded in support, even though many had just voted with Levesque.

The media and delegates focused special attention on Pierre Marc Johnson, 38, son of a former Quebec premier, who is widely viewed as Levesque's likely successor to head the party. Johnson staunchly backed Levesque's resolution.