VPSA technology oxygen generator

The present invention discloses a VPSA technology oxygen generator, which comprises a main gas inlet, a compressor, an electromagnetic valve, a molecular sieve barrel 1, a molecular sieve barrel 2, a communication valve and a gas storage cylinder, by arranging the two molecular sieve barrels, when air flows into one of the molecular sieve barrels through the communication pipe, nitrogen passing through a molecular sieve of the molecular sieve barrel is adsorbed, and oxygen flows into the gas storage cylinder, so that the oxygen is absorbed; meanwhile, nitrogen in the other molecular sieve barrel is pumped out through a negative pressure air inlet of the compressor to be vacuumized, the two molecular sieve barrels are communicated by opening the communicating valve, a small part of oxygen in the other molecular sieve barrel can be pumped into the molecular sieve barrel with air to further blow out the nitrogen, the communicating valve is closed again, the nitrogen is exhausted thoroughly, and almost no nitroge