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Using BLDC wheels is common on electric transport. A wheel is a multiphase motor, where each phase(coil) is separated from power source(battery) with some kind of transistor, driven by PWM-like signal. Almost like in the following illustration: enter image description here

However, there also exists "recuperation". When you'll manage to press brakes - a motor should turn into a generator and charges battery again. But I've never seen any scheme or model of it.. You cannot simply push current in backwrd direction through fets.

How is this implemented? What approaches do you know (if there are many)?

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  • \$\begingroup\$ It's called regeneration. What makes you think you can't push current backwards through MOSFETs? They conduct in either direction. \$\endgroup\$ – Spehro Pefhany Apr 3 at 18:57
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    \$\begingroup\$ A buck converter from battery to wheels uses exactly the same components as a boost converter from wheels to battery, only the switch timing differs. \$\endgroup\$ – Neil_UK Apr 3 at 19:01
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    \$\begingroup\$ Sure you can push it backwards. You can even push it backwards even when the MOSFET is off due to the parasitic body diode (as well as the external flyback diodes antiparallel to the MOSFET). MOSFETs can only block current flow in one direction as a result, after all. It's more efficient if you actually switch the MOSFET on though so it conducts through the resistance of the MOSFET rather than through the diode. You use the same hardware but you code the switches to fire in a different sequence. Convenient, isn't it? \$\endgroup\$ – Toor Apr 3 at 19:07
  • \$\begingroup\$ @SpehroPefhany Ah I thought of transistor is like diode, that can conduct in one direction; And with "incase switch", that's operated with current(or voltage in case of mosfet) \$\endgroup\$ – xakepp35 Apr 3 at 19:30
  • \$\begingroup\$ @Toor I thought that diodes drawn to the right of transistors are soldered just to protect transistors from breaking due to self-induction current... \$\endgroup\$ – xakepp35 Apr 3 at 19:34

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