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FedorBel / bldc-driver

3-phase driver for bldc motor, based on stm32 and l6234.
MIT License
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DC bus current sensing #2

Open FedorBel opened 3 years ago

FedorBel commented 3 years ago

How to measure dc bus in a 3-phase half bridge inverter.

FedorBel commented 3 years ago

Article from STMicroelectronics on low-side current sensing using shunt resistor and op-amp.

FedorBel commented 3 years ago

image

FedorBel commented 3 years ago

Or just use ACS712 5A current sensor.

FedorBel commented 3 years ago

Measuring with ACS712 5A is not very good.

image.png

In fact, i only need to measure 0-4 A, there's less then 1v dif when measuring (not stable supply voltage can end with bad results). Better build shunt + op-amp sheme.

FedorBel commented 3 years ago
  1. Advice on Current Sensing for new board design.
  2. Current Sensing Tutorial.
FedorBel commented 3 years ago

Current-sense amps:

  1. INAx180
  2. INAx181 - bi-dir
  3. INA381 - amp+comp
  4. INA250 - shunt+amp