A special committee to coordinate all governmental policies involving the Soviet Union has been authorized by President Carter, to be centered in the State Department.

Officials disclaimed yesterday that any particular fault or problem inspired the new interagency group, but its creation comes at a low point in U.S.-Soviet relations.

President Carter, however, has acknowledged he was surprised by the severity of the Soviet reaction to his human rights campaign. The outright Soviet rejection in March of U.S. proposals for major cuts in strategic nuclear arms levels was accompanied by suspicion in Moscow of Carter administration intentions.

One source of Soviet indignation was a U.S. decision to increase the power of Radio Liberty and Radio Free Europe broadcasts to Eastern Europe, which American strategists treated as an isolated issue. To the Russians it looked like deliberate goading, part of a new pressure campaign.

A State Department spokesman said yesterday that "the need was felt for a central coordinating mechanism which would be aware of all of the contacts, and all of the activities, of U.S. agencies" involving the Soviet Union.

The new committee will be co-chair by Marshall D. Shulman, chief adviser to Secretary of State Cyrus R. Vance on Soviet affairs, and George S. Vest, assistant secretary of state for European affairs. It was authorized in a July 15 memorandum signed by presidential National Security Adviser Zbigniew Brzezinski.

This "is not a policy-making group," State Department spokesman John H. Trattner stressed yesterday. Normally, coordination of U.S. policy toward the Soviet Union has been handled through the National Security Council staff.

The new committee indicates that President Carter wants tighter coordination than the relatively small NSC staff can supply.

Agencies throughout the government are involved in policies affecting the Soviet Union.They include not only those directly responsible for national security, but also such departments as Transportation, Interior, Housing and Urban Development, and the Environmental Protection Agency, the Federal Maritime Commission, Civil Aviation Board and numerous others.

Principal representatives on the new committee, known as the Inter-agency Coordinating Committee on U.S.-Soviet Affairs, will be officials from State, Defense, Treasury, Central Intelligence Agency, National Security Council, Arms Control and Disarmament Agency, Agriculture, Commerce, National Aeronautics and Space Agency, and the President's science adviser.

The group is instructed to meet regularly and often, to monitor activities affecting the Soviet Union, supplying the President and other senior officials with "a comprehensive picture of such affairs, and to bring to their attention interagency matters requiring their attention."