Simulation of a fuel injection valve and drive circuit is shown here. The state-average boost converter is modeled with the 100V output supplying the simplified current control drive electronics. The current control logic module detects the current through the injector. At initial turn-on, the switch applying the boost voltage is closed, and the current in the injector will rise rapidly. When the current reaches 10 Amps, that switch is opened and the controller continues to modulate the battery voltage switch, to maintain 10 Amp. At turn off, all the switches are opened, including the low side switch. This forces the inductive current to flow through a clamping 50V Zener diode, which causes the residual current to drop off sharply. In the lower right of the schematic, an ideal pressure source, a snubber and fuel line have been added to the injector inlet, to represent the fuel rail and feed lines. A simple orifice and calibrated tube have been connected to the outlet, to represent the injector nozzle and to measure the fuel quantity injected during each fire cycle.

Circuit Snapshot:
Refer to the attached snapshot "ex_inject_v2.PNG" below.

How to use the Example:
Download the attached "" and unzip the contents. Open the ex_inject_v2.ai_dsn in SaberRD and run the experiment listed in the Experiment Analyzer.
For more details of the design, how to run the design, etc., refer to the README.pdf file attached.

This design example works only in SaberRD Commercial version 2016.03 & higher.
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