Sudden one to two second electrical motor noise

[Y Murphy Y]

Please direct me to the right thread if this has been covered. I'm used to the normal sounds of my Model 3 and Model Y while charging. On three separate occasions I've had a sudden loud one to two second noise from my Model Y that's started and stopped as my batteries gets near 90%. It sounds like an electrical motor engaging while I'm sitting (I know that's not possible—just trying to find a way to describe this). Today it's continued for at least 45 minutes while driving. It will be quiet for 30 seconds to a minute or two and then the whole car kind of pulses for a second. I've made recordings I could upload. Thank you in advance to anyone that's got an idea on this.