Patent attributes
A multiple-turbocharger system for an internal combustion engine includes a first turbocharger comprising a first compressor driven by a first turbine, the first turbine operable to be driven by exhaust gas from the engine; a second turbocharger comprising a second compressor driven by a second turbine, the second turbine operable to be driven by exhaust gas from the engine; a first conduit arranged for supplying exhaust gas from the engine to the first turbine, and a second conduit arranged for supplying exhaust gas from the engine to the second turbine; and a valve coupled with the second conduit and switchable between an open condition allowing exhaust gas flow from the second conduit to the second turbine, and a closed condition substantially preventing exhaust gas flow from the second conduit to the second turbine but allowing a leakage flow to the second turbine sufficient to keep the second turbine rotating.