Braking Methods of Induction Motor in VFD
Figure 1. Variable Frequency Drive outline schematic thanks to Stephen Collings.

Yes, the VFD will continue to commutate during deceleration - this time with the frequency lower than that of the motor so that the slip is negative. The current is dumped into the DC link (C in Figure 1).

Two things can happen here:


If the DC link is shared with other drives and another motor is using power then an energy saving is made and the regenerated power is consumed by the other motor.
If not, then the DC link voltage starts to rise. At some point the excess energy will have to be dumped to prevent damage to the input diodes, C and the switching transistors. Usually a link voltage monitor will switch use a power MOSFET to connect a power resistor across C to divert the current. This can be PWM controlled to modulate the degree of dumping as required.




Figure 2. A typical IGBT VFD module. Source: Fuji Electric.

The module shown in Figure 2 includes a three-phase rectifier, the P-N output to the smoothing capacitor, P1-N1 input to the IGBT section and the UVW outputs to the motor. The braking resistor will be connected between P1 and B.