Compressor flow control
AssigneeFord Global Technologies, LLC
InventorsDeborah M. Bjorge, Julia Helen Buckland
Life of this patent
Estimating the term…
Abstract
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.
Claims17
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.
A method for a turbocharged engine with a first and second compressor, comprising:
- under high engine load, opening a first compressor recirculation valve of the first compressor and adjusting a second compressor recirculation valve of the second compressor based on a pressure ratio and mass-flow rate of the second compressor;
- and
- under low to medium engine load, adjusting the second compressor recirculation valve of the second compressor based on the pressure ratio and mass-flow rate of the second compressor.
An engine system, comprising:
- an engine;
- first and second compressors supplying air to the engine;
- a first compressor recirculation valve adjustable to two restriction levels;
- a second compressor recirculation valve adjustable to three or more restriction levels;
- and
- a controller including instructions for operating the first and second compressor recirculation valves concurrently when a difference between mass-flow through a throttle upstream of the engine and mass-flow at a surge line is above a second threshold.
Dependencies are inferred from the claim text.