Guru
Joined: 08/02/2015
Location: New ZealandPosts: 962
| Posted: 03:56am 22 Jul 2021 |
Have made more progress on this project.
For analog measurements the Pico doesn't have enough ADC inputs, so will use an analog multiplexer with a common output noise filter going to a single ADC.
Temperature measurements, will use the MCP9701 active linear thermistors, have used these before, they are great.
AC voltage measurement, will use a ZMPT100B 2mA voltage sense transformer coupled to an active full wave rectifier\peak detector.
DC battery voltage sensing is a simple resistive divider, the DC voltage selects the 50Hz modulation depth of the H-Bridge, feed forward.
Current measurement goes to a latching trip circuit, to inform the CPU an overload has occurred, I'm not going to measure it for any display purposes.
PicoController.pdf
To do: Outputs for status running, LED's, LCD display, HBridge modules Main Caps pre-charge, 1-Wire network., external shutdown input.
Feel free to comment on the design, no doubt there are better ways to implement some of this.
Cheers
Mike
Edited 2021-07-22 20:23 by Solar Mike