Advanced powertrain benchmarking via selective interrupt and control
Modern engine hardware and controls are very complex, requiring equally complex testing methodologies when performing powertrain benchmarking. Tethered benchmarking connects an engine in a test cell to a complete vehicle through an extended wire harness, enabling evaluation of stock powertrain calibration without manufacturer support. This test method can be used to develop brake specific fuel consumption maps and evaluate control strategies. However, this testing is limited to factory “on calibration” test points. To enable the evaluation of off-calibration powertrain operation, the selective interrupt and control (SIC) test capability was developed as part of an EPA evaluation of a 1.6 L EcoBoost® engine. A control and data acquisition device sits between the stock powertrain controller and the engine; the device selectively passes through, or modifies, control signals while also simulating feedback signals.