High and low pressure turbocharger system with compressed gas tank

Patent metadata

Field	Value
Publication number	US-9890696-B2
Application number	US-201414535720-A
Country	US
Kind code	B2
Filing date	Nov 7, 2014
Priority date	Nov 15, 2013
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

A turbocharger system and method for a vehicle, wherein the system comprises a high pressure turbocharger and a low pressure turbocharger. Both the high and low pressure turbochargers are driven by exhaust gas on an exhaust side of the turbochargers. The system further comprises a first bypass conduit that bypasses the low pressure turbocharger during set events.

First claim

What is claimed is:

1. A turbocharger system for a vehicle, the turbocharger system comprising:
a high pressure turbocharger and a low pressure turbocharger, both the high and low pressure turbochargers being drivable by exhaust gas on an exhaust side of the high and low pressure turbochargers, both the high and low pressure turbochargers being arrangeable to compress air on an air intake side of the high and low pressure turbochargers when exhaust gas drives the high and low pressure turbochargers, the high pressure turbocharger being positioned upstream of the low pressure turbocharger with reference to exhaust gas flow and downstream of the low pressure turbocharger with reference to air flow;
an exhaust gas manifold in fluid communication with an exhaust gas manifold conduit;
a tank in fluid communication with the exhaust gas manifold, wherein the tank is arranged to push compressed gas as a pulse into the exhaust manifold during a predetermined pulse duration time period for initial compressor spin up in the high pressure turbocharger;
a control unit connected to a pulse regulation unit for regulating the pulse duration time period;
a tank valve connected to the tank, wherein the tank valve is controllable by the pulse regulation unit;
a first pipe system connecting the low pressure turbocharger to the high pressure turbocharger for fluid communication between the high and low pressure turbochargers on the air intake side, the first pipe system comprising a first conduit connected to an inlet of the low pressure turbocharger and to inlet air, a second conduit connecting an outlet of the low pressure turbocharger to an inlet of the high pressure turbocharger, a first bypass conduit connected to the second conduit on one end and essentially directly to ambient air on another end, and a first valve positioned in the first bypass conduit arranged to open to allow air flow essentially directly from ambient air to the second conduit, wherein the first valve is configured to be opened in combination with the pulse to avoid underpressure in the second conduit; and
a second pipe system connecting the high pressure turbocharger to the low pressure turbocharger for fluid communication between the high and low pressure turbochargers on the exhaust gas side.

2. The turbocharger system according to claim 1 wherein the first bypass conduit is connected to the first conduit on the other end, and wherein the first conduit is connected essentially directly to ambient air.

3. The turbocharger system according to claim 1 wherein the first valve is a passive valve that is configured to open when the pressure in the second conduit is lower than the pressure in the first conduit.

4. The turbocharger system according to claim 1 wherein the first valve is an active valve controllable by the control unit, and wherein the control unit is configured to open the first valve when a lower pressure in the second conduit relative to the first conduit is present or anticipated.

5. The turbocharger system according to claim 1 wherein the first pipe system comprises an air inlet pipe conduit connecting an outlet of the high pressure turbocharger and an intake manifold of an engine on the air intake side, a second bypass conduit connecting the second conduit to the intake manifold, and the second valve positioned in the second bypass conduit for the controlling air flow from the second conduit to the air intake manifold, and wherein the second valve is configured to open when the pressure in the second conduit is higher than pressure in the inlet pipe conduit after the higher pressure turbo charger.

6. The turbocharger system according to claim 1 wherein the second pipe system comprises the exhaust gas manifold conduit connecting the exhaust gas manifold with an inlet of the high pressure turbocharger, a third conduit connecting an outlet of the high pressure turbocharger with an inlet of the low pressure turbocharger, a third bypass conduit connecting the exhaust gas manifold conduit to the third conduit, and a third valve for controlling exhaust gas flow between the exhaust gas manifold conduit and the third conduit, the third valve being configured to open when the high pressure turbocharger has reached an upper limit on rotational speed or whenever to improve the efficiency of the turbocharger system.

7. A method for controlling a turbocharger system for a vehicle, wherein the turbocharger system comprises a high pressure turbocharger and a low pressure turbocharger, both the high and low pressure turbochargers being drivable by exhaust gas on an exhaust side of the high and low pressure turbochargers, both the high and low pressure turbochargers being arranged to compress air on an air intake side of the high and low pressure turbochargers when exhaust gas drives the high and low pressure turbochargers, the high pressure turbocharger being positioned upstream of the low pressure turbocharger with reference to exhaust gas flow and downstream of the low pressure turbocharger with reference to air flow, wherein the turbocharger system further comprises a first pipe system connecting the low pressure turbocharger to the high pressure turbocharger for fluid communication between the high and low pressure turbochargers on the air intake side and a second pipe system connecting the high pressure turbocharger to the low pressure turbocharger for fluid communication between the high and low pressure turbochargers on the exhaust gas side, the first pipe system comprising a first conduit connected to an inlet of the low pressure turbocharger and to inlet air, a second conduit connecting an outlet of the low pressure turbocharger to an inlet of the of the high pressure turbocharger, a first bypass conduit connected to the second conduit on one end and essentially directly to ambient air on another end, and a first valve positioned in the first bypass conduit, and wherein the turbocharger system further comprises an exhaust gas manifold in fluid communication with an exhaust gas manifold conduit, a tank in fluid communication with the exhaust gas manifold, a tank valve connected to the tank, and a control unit connected to a pulse regulation unit, the method comprising:
controlling the tank valve by the pulse regulation unit;
pushing, by the tank, compressed gas as a pulse into the exhaust manifold during a predetermined pulse duration time period for initial compressor spin up in the high pressure turbocharger, wherein the control unit is configured to regulate the pulse duration time period; and
combining the pulse with opening of the first valve to avoid underpressure in the second conduit.

8. The method according to claim 7 wherein the first bypass conduit is connected to the first conduit on the other end, and wherein the first conduit is connected essentially directly to ambient air.

9. The method according to claim 7 wherein the first valve is a passive valve that opens when the pressure in the second conduit is lower than the pressure in the first conduit.

10. The method according to claim 7 wherein the first valve is an active valve controlled by the control unit, and wherein the method further comprises opening the first valve, by the control unit, when a lower pressure in the second conduit relative to the first conduit is present or anticipated.

11. The method according to claim 10 wherein the first bypass conduit is connected to the first conduit on the other end, and wherein the first conduit is connected essentially directly to ambient air.

Assignees

• Volvo Car Corp

Inventors

• Almkvist Goran
• Bjorkholtz Jonas J

Classifications

• F02B37/013 Primary

  with exhaust-driven pumps arranged in series · CPC title

• F02B37/10

  at least one pump being alternatively {or simultaneously} driven by exhaust and other drive, {e.g. by pressurised fluid from a reservoir or an engine-driven pump} · CPC title

• F02B37/16

  by bypassing charging air · CPC title

• F02B37/004

  with exhaust drives arranged in series · CPC title

• F02D41/0007

  for control of turbo-charged or super-charged engines (control of the pumps per se F02B37/12) · CPC title