Officials responded to the crash around 11 am near the intersection of Bullard and DeWolf.
They say the woman suffered a medical emergency, causing her to swerve and crash into the pole.
The transformer sitting on top of the pole caught fire and it quickly spread to a nearby field.
Fire crews were able to work fast and contain the fire before it could damage any structures.
It still burned about three acres of grass. The driver is expected to be okay.