When the nation's governors debated today what should be done with the oil companies' windfall profits, the corporations's best friend came from oil-poor Virginia.

John N. Dalton, the pro-business Republican from Richmond, argued in an emotional voice before his 27 colleagues at the National Governors' Conference that they should not support what is essentially President Carter's plan for taxing the profits.

After an extended, sometime bitter debate Dalton failed in his argument against what he said would be more federal "social welfare programs." Others, including Maryland Gov. Harry Hughes, a Democrat, claimed the government has a specific responsibility to help families squeezed by sharp higher fuel costs.

Dalton said today that his was not "a vote against poor people. We have our regular welfare plans for people who are unable to cope with" higher fuel costs.

Hughes, who had left the conference by the time of the formal vote on the tax measure earlier had argued against Dalton. Hughes had maintained yesterday that it was "logical, sensible and humand" for the government to assist the low-income families in meeting the fuel costs.

The resolution approved yesterday by the governors was basically an endorsement of Carter's plan for oil decontrol. Under Carter's plan, there would be a tax of 50 percent on profits generated by the recent rapid rise in oil prices. The revenue would be used to aid urban mass transit systems energy research and the poor.

The House last month approved a 60 percent tax on windfall profits resulting from decontrol of domestic oil prices a bill that would raises an estimated $37 billion between 1980 and 1984.

During today's debate on oil policy which split for the most part between the sun belt and the snow belt, Maine Gov. Joseph E. Brennan complaned that an energy policy that ignores the poor in his state would force people to choose "between freezng and eating."

Texas Gov. William Clements has said that he found Brennan's comment about freezing and eating "somewhat offensive."

Clements and Dalton argues loudly today that any use of oil company profits other than energy development would be counterproductive because iwould take money away from the nation's most important problem -- finding its own sources of energy.

Dalton said in an interview that the profits estimated to amount to more than $60 billion in the next five years, could prompt buildng if "one or two"$1 billion plants in Virginia that will turn coal into fuel oil.

The Republican governor of the nation's sixth-leading coal-producing state said the plants could be built near the coal fields in the Southwest section of Virginia. Dalton said a state study two years ago indicates that the New River in that section of the state can provide the large amounts of water needed for coal liquification and gastification.

It was the second time during the conference that the conservative Dalton clashed with Hughes and others over what the Virginian saw as an economic issue. Earlier in the conference Dalton had managed to block a resolution that would have created a separate national holiday honoring Martin Luther King Jr. as too costly for state governments.