Hi Guys,
Previously I have posted a question but due to the circuit diagram in the post, it deviated from the original question. If you haven't seen the previous post, it's fine. I'll explain everything clearly below.
I'm working on a project where I need to control a diesel injector. This is an academic project, if it goes well it shall get into industry level, so looking for a standard Good approach.
The diesel injector is activated by an Arduino(this is the initial setup, and will soon switch over to stm32). The diesel injector is outside the engine in a separate setup which gets supplied by a constant pressure fuel pump driven by an ac motor(const speed). I'm using a MOSFET to control the injector. The MOSFET I'm using is IRLZ44N. The drain of the MOSFET is connected to negative terminal of the injector and source of the MOSFET is connected to the negative terminal of the injector's power supply (i have added flyback diode for safety circuit for injector). The Arduino controls the injector via the gate pin of the MOSFET. The power supply for injector is 12v SMPS.
The Arduino gets signal from the injector's supply and control wires, we tapped these 2 wires and gave them to an optocoupler pc817. This optocoupler's output is given to the digital pin of Arduino. Arduino mirrors this signal to the gate pin of the MOSFET. You might wonder why I'm using Arduino, if the setup goes well, I will alter the pulse in future. So that's why I'm using it.
Issues faced:
1) this setup worked as intended, but after sometime, that is, after 2-3 weeks of testing this setup, the injector has gone. We didn't notice any smoke or smell, but the injector stopped actuating. We lost 2 injectors in this journey.
2) we started the engine and maintained in idling for 60seconds and started our injector setup, we collected around 90ml of fuel at idling, which feels abnormal.
Now, I need a reliable approach for this project. It would be really helpful if someone can come up with some idea for this.
Thank you in advance