Compressor flow control

摘要

An engine system is provided. The system comprises an engine, first and second compressors supplying air to the engine, a first compressor recirculation valve adjustable to two restriction levels, and a second compressor recirculation valve adjustable to three or more restriction levels. In this way, the first and second compressor recirculation valves may be controlled to avoid compressor surge while providing a sufficient amount of boost to meet power demands.

主权项

1. A method for a turbocharger system having a first and second compressor, comprising:
under a first condition, opening a first compressor recirculation valve (CRV) of the first compressor; under a second condition, opening the first CRV and adjusting a restriction amount of a second CRV of the second compressor; and under a third condition, closing the first CRV and adjusting the restriction amount of the second CRV, the second condition including a difference between mass-flow through a throttle and mass-flow at a surge line being greater than a mass-flow through the first CRV.