Back to results
US 9,284,898 B2Granted
Method and system for binary flow turbine control
AssigneeFord Global Technologies, LLC
InventorsJulia Helen Buckland, Stephen Lee Cooper, Brad Alan Boyer, Amey Y. Karnik, Jeffrey Allen Doering
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for adjusting the opening of a scroll valve of a binary flow turbine. Scroll valve adjustments are used at different engine operating conditions to improve engine performance and boost response. Scroll valve adjustments are coordinated with wastegate and EGR valve adjustments for improved engine control.
Claims16
A method for an engine, comprising:
- in response to a tip-in, adjusting an opening of a scroll valve coupled to an outer scroll of a multi-scroll exhaust turbine to reduce turbo lag;
- adjusting an amount of exhaust gas recirculated to an engine intake based on the scroll valve opening;
- wherein adjusting the opening of the scroll valve includes reducing the opening of the scroll valve, the reducing based on an estimated or measured turbine speed or boost pressure at the tip-in;
- wherein the reducing based on the turbine speed includes, as a difference between the estimated or measured turbine speed and a requested turbine speed increases, moving the scroll valve towards a fully closed position, and wherein the reducing based on the boost pressure includes, as a difference between an estimated or measured boost pressure and a requested boost pressure increases, moving the scroll valve towards the fully closed position;
- and
- wherein the adjusting of the scroll valve is further based on an ambient air density, the scroll valve moved towards the fully closed position as ambient air density decreases.
3 more elements
A method for an engine, comprising:
- in response to a tip-in, closing a scroll valve coupled to an outer scroll of a multi-scroll turbine for a duration;
- reducing an amount of EGR delivered to the engine for the duration,
- wherein the duration is based on turbine speed following the tip-in.
An engine system, comprising:
- an engine;
- a turbocharger for providing a boosted aircharge to the engine, the turbocharger including an intake compressor and an exhaust turbine, the exhaust turbine including a first outer scroll and a second inner scroll;
- a scroll valve coupled between an engine exhaust manifold and an inlet of the first outer scroll;
- a wastegate included in a bypass coupled between an inlet and an outlet of the turbine;
- an EGR system with an LP-EGR valve in an LP-EGR passage for recirculating exhaust gas from downstream of the turbine to upstream of the compressor, and an HP-EGR valve in an HP-EGR passage for recirculating exhaust gas from upstream of the turbine to downstream of the compressor;
- and
- a controller with computer readable instructions for,
- in response to a tip-in, closing the scroll valve until turbine speed is higher than a threshold speed;
- and
- adjusting each of the LP-EGR valve and the HP-EGR valve to vary a ratio of HP-EGR to LP-EGR based on the scroll valve closing.
7 more elements
Dependencies are inferred from the claim text.