OpenECU Engine Management System for a 3 Cylinder, 2 Stroke Heavy Fuel Engine
The engine program Pi Innovo was commissioned to work on was a three cylinder, two stroke, spark-ignited, heavy fuel engine with two injectors per cylinder. Furthermore the circuit requirements to support the specific sensors and actuators required a semi-custom hardware solution. This particular engine configuration complicated the selection of a control system.
To quickly deliver a rapid controls prototyping solution, Pi Innovo systems engineering implemented a system architecture utilizing two OpenECU M250 rapid controls prototyping ECUs in a master-slave configuration. The master M250 consumed all input signals and drove the three spark commands, oil pump and three fuel injectors. The slave M250 was connected to the master via a high-speed (1000 kbps) CAN channel and was responsible for driving the three injectors that would release the air-fuel mixture from the pre-chamber into the combustion chamber.
Pi Innovo also conducted a high-level failure mode analysis that included identifying failure modes for each sensor and actuator, the impact on rated engine power, rate of occurrence of the failure and the sensitivity of engine performance to variations in component characteristics.
The customer wanted to focus on development of the base engine, and not the controls. The engine control strategy software needed to be effective at exercising all the unique features of the engine design, but simple enough that it could be calibrated by junior engineers and non-software oriented persons. Pi Innovo developed a set of custom model based control strategies and provided training that allowed the customer to quickly tune and evaluate changes to the engine.
Results and Impact
A balance of functionality and rigor was struck in providing the right solution for the task at hand. In a short period Pi Innovo was able to develop a custom solution tailored to meet the customer’s specific needs.
OpenECU Simulink API
Rapid controls prototyping
Model based engine control strategies
Pi Innovo engineering services