Note to other groups working on their final project:

• Label your wires with some tape [especially your primary and secondary windings of your transformer. But if you didn’t, there’s always the connectivity test]
• If you’re considering not using a transformer, reconsider. Actually figuring out what you need to make a transformer function properly is far more interesting than just thinking about a turns ratio. Also remember to use sandpaper to remove the enamel from the ends of your magnet wire when you want to connect it.  
• The ADC on the STM32 can’t run faster than 10kHz because it requires 10us cycle time.
• Check your grounds. Consider connecting your microcontroller and half bridge grounds.
• The oscilliscope is your best friend.  If you are having an issue, the first step is to start probing your nodes to see if you are getting what you’d expect.
• When laying out a PCB, put a lot of thought into your power paths.  Doing this early will save you a lot of time in the long run.
• Ground planes are an amazing thing.
• Learning new skills [ie. PCB design] will put you behind, so try to be realistic about your time.  However, it is totally worth it.

Future Work

The next step for our project  would be to get our PCBs working together and hook our system up to a solar panel.

In the future, we would like to expand the inverter system to output three phase AC to drive an induction motor.  We would also like to implement a maximum power point tracker and the final functionality of a three-port inverter.  That is, we would like to enable charging of the batteries from the “grid-tied” load when there is no power coming from the solar panel.

Acknowledgements

We would like to thank Ned Danyliw, Andrew Ponec, Hong En Chew, Steven Clark, and Professor Bill Dally for their support, patience, and motivation in this project and throughout the quarter.