Three-level roots water-ring intelligent frequency conversion control vacuum system and control method therefor

摘要

A three-level roots water-ring intelligent frequency conversion control vacuum system comprises a first-level roots mechanical vacuum pump (1), a second-level roots mechanical vacuum pump (2), and a traction liquid ring pump (3). The first-level roots mechanical vacuum pump (1) and the second-level roots mechanical vacuum pump (2) are each provided with a frequency conversion motor, a frequency converter (18, 19), and an exhaust port condenser (8, 4). An inlet end of the first-level roots mechanical vacuum pump (1) and an outlet end of the second-level roots mechanical vacuum pump (2) are each provided with a pressure transmitter (11, 12), and the pressure transmitters(11, 12) and the frequency converters (18, 19) are all connected to a control cabinet. By means of pressure feedback values provided by the pressure transmitters (11, 12) on each level, the rotating speeds of the roots mechanical vacuum pumps are adjusted by using the frequency converters, and pressure difference values are adjusted by means of bypass pipelines (17). A control method for the three-level roots water-ring intelligent frequency conversion control vacuum system. The rotating speeds of the roots mechanical vacuum pumps are respectively adjusted by using the frequency converters, and the pressure difference values are adjusted by means of the bypass pipelines (17), so that the first-level roots mechanical vacuum pump (1) and the second-level roots mechanical vacuum pump (2) have balanced pressure differences and safely run.