PWM controller with synchronous braking

Question

I'm a student and I'm attempting to study how to use two different PWM signals to continuously drive and brake a brushed 12 V motor from an microcontroller.

First frequency will be around 4 kHz (for drive, red) and the second will be ten times the first, so around 40 kHz (for brake, green).

My idea is braking during low (or zero) side of the main power signal, using a NOR or NAND gate to make sure you don't destroy the two MOSFETs

Also, motor need to spin in only one direction, so there is no request for a full bridge.

Is this possible? I read around about Locking Anti-Phase, but it doesn't seems like my idea.

Answer 1

^{simulate this circuit – Schematic created using CircuitLab}

$$V_m= D_{M_1}\cdot V_{bat}=(1-D_{M_2})\cdot V_{bat}$$ $$V_m= I_a\cdot R_a + \dfrac{dI_a}{dt}L_a + E_a$$

M1 and M2 are synchronous switching, i.e when the one turns ON, the other turns OFF. D is the duty ratio of the upper switch M1, while 1-D is the duty ratio of the lower switch M2.

If the motor BEMF voltage Ea is lower than applied motor voltage, then it is motor mode. If the motor BEMF voltage Ea is higher than applied voltage Vm, then it becomes a generator - regenerative braking.